bims-amsmem 2022-04-17 papers

bims-amsmem

Biomed News

on AMPK signaling mechanism in energy metabolism

Issue of 2022–04–17
33 papers selected by
Dipsikha Biswas, Københavns Universitet

Differentiated modulation of signaling molecules AMPK and SIRT1 in experimentally drug-induced hepatocyte injury.
The role of AMPK-dependent pathways in cellular and molecular mechanisms of metformin: a new perspective for treatment and prevention of diseases.
FGF21 Reduces Lipid Accumulation in Bovine Hepatocytes by Enhancing Lipid Oxidation and Reducing Lipogenesis via AMPK Signaling.
The Protective Effect of Pilose Antler Peptide on CUMS-Induced Depression Through AMPK/Sirt1/NF-κB/NLRP3-Mediated Pyroptosis.
Biochemical purification uncovers mammalian sterile 3 (MST3) as a new protein kinase for multifunctional protein kinases AMPK and SIK3.
L-theanine prevents progression of nonalcoholic hepatic steatosis by regulating hepatocyte lipid metabolic pathways via the CaMKKβ-AMPK signaling pathway.
Hypothermia preconditioning improves cardiac contractility after cardiopulmonary resuscitation through AMPK-activated mitophagy.
Stevioside Enhances the Anti-Adipogenic Effect and β-Oxidation by Activating AMPK in 3T3-L1 Cells and Epididymal Adipose Tissues of db/db Mice.
The mTORC1/AMPK pathway plays a role in the beneficial effects of semaglutide (GLP-1 receptor agonist) on the liver of obese mice.
STE20 phosphorylation of AMPK related kinases revealed by biochemical purifications combined with genetics.
Epigenetic Upregulation of H19 and AMPK Inhibition Concurrently Contribute to S-Adenosylhomocysteine Hydrolase Deficiency-Promoted Atherosclerotic Calcification.
Novel pyrazolo[3,4-b]pyridine derivatives: Synthesis, structure-activity relationship studies, and regulation of the AMPK/70S6K pathway.
Psoralen Suppresses Lipid Deposition by Alleviating Insulin Resistance and Promoting Autophagy in Oleate-Induced L02 Cells.
Maackiain protects against sepsis via activating AMPK/Nrf2/HO-1 pathway.
Calcium-binding protein 39 overexpression promotes macrophages from 'M1' into 'M2' phenotype and improves chondrocyte damage in osteoarthritis by activating the AMP-activated protein kinase/sirtuin 1 axis.
Metformin alleviates nickel-refining fumes-induced aerobic glycolysis via AMPK/GOLPH3 pathway in vitro and in vivo.
Mesenchymal Stem Cells and their Derived Exosomes Promote Malignant Phenotype of Polyploid Non-Small-Cell Lung Cancer Cells through AMPK Signaling Pathway.
Polyphyllin I alleviates inflammatory injury in mice with gestational diabetes through AMPK pathway.
Metformin improves renal injury of MRL/lpr lupus-prone mice via the AMPK/STAT3 pathway.
Capsaicin ameliorates intermittent high glucose-mediated endothelial senescence via the TRPV1/SIRT1 pathway.
Nandrolone Supplementation Promotes AMPK Activation and Divergent 18[FDG] PET Brain Connectivity in Adult and Aged Mice.
Combined Levo-tetrahydropalmatine and diphenyleneiodonium chloride enhances antitumor activity in hepatocellular carcinoma.
Epigallocatechin-3-gallate ameliorates hepatic damages by relieve FGF21 resistance and promotion of FGF21-AMPK pathway in mice fed a high fat diet.
Ligustilide ameliorates cognitive impairment via AMPK/SIRT1 pathway in vascular dementia rat.
Structure-Activity Relationship of Synthetic Ginkgolic Acid Analogs for Treating Type 2 Diabetes by PTPN9 Inhibition.
Enhanced pentose phosphate pathway activity promotes pancreatic ductal adenocarcinoma progression via activating YAP/MMP1 axis under chronic acidosis.
Abietic acid alleviates endoplasmic reticulum stress and lipid accumulation in human primary hepatocytes through the AMPK/ORP150 signaling.
Defects of Nutrient Signaling and Autophagy in Neurodegeneration.
Pterostilbene and Its Derivative 3'-Hydroxypterostilbene Ameliorated Nonalcoholic Fatty Liver Disease Through Synergistic Modulation of the Gut Microbiota and SIRT1/AMPK Signaling Pathway.
Explore the Mechanism of Astragalus mongholicus Bunge against Nonalcoholic Fatty Liver Disease Based on Network Pharmacology and Experimental Verification.
Ferrous Bisglycinate Supplementation Modulates Intestinal Antioxidant Capacity via the AMPK/FOXO Pathway and Reconstitutes Gut Microbiota and Bile Acid Profiles in Pigs.
Retraction notice to "Echinacoside improves diabetic liver injury by regulating the AMPK/SIRT1 signaling pathway in db/db mice" [Life Sci. 271 (2021) 119237].
Schisandrin B mitigates hepatic steatosis and promotes fatty acid oxidation by inducing autophagy through AMPK/mTOR signaling pathway.

Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2022 Apr 12.

Differentiated modulation of signaling molecules AMPK and SIRT1 in experimentally drug-induced hepatocyte injury.

Lea Njeka Wojnarova, Nikolina Kutinova Canova, Mahak Arora, Hassan Farghali.

AIM: Currently available medicines have little to offer in terms of supporting the regeneration of injured hepatic cells. Previous experimental studies have shown that resveratrol and metformin, less specific activators of AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1), can effectively attenuate acute liver injury. The aim of this experimental study was to elucidate whether modulation of AMPK and SIRT1 activity can modify drug/paracetamol (APAP)-induced hepatocyte damage in vitro.
METHODS: Primary rat hepatocytes were pretreated with mutual combinations of specific synthetic activators and inhibitors of SIRT1 and AMPK and followed by a toxic dose of APAP. At the end of cultivation, medium samples were collected for biochemical analysis of alanine-aminotransferase and nitrite levels. Hepatocyte viability, thiobarbituric reactive substances, SIRT1 and AMPK activity and protein expression were also assessed.
RESULTS: The harmful effect of APAP was associated with decreased AMPK and SIRT1 activity and protein expression alongside enhanced oxidative stress in hepatocytes. The addition of AMPK activator (AICAR) or SIRT1 activator (CAY10591) significantly attenuated the deleterious effects of AMPK inhibitor (Compound C) on the hepatotoxicity of APAP. Furthermore, CAY10591 but not AICAR markedly decreased the deleterious effect of APAP in combination with SIRT1 inhibitor (EX-527).
CONCLUSION: Our findings demonstrate that decreased AMPK activity is associated with the hepatotoxic effect of APAP which can be significantly attenuated by the administration of a SIRT1 activator. These findings suggest that differentiated modulation of AMPK and SIRT1 activity could therefore provide an interesting and novel therapeutic opportunity in the future to combat hepatocyte injury.

DOI: https://doi.org/10.5507/bp.2022.018
Inflammopharmacology. 2022 Apr 13.

The role of AMPK-dependent pathways in cellular and molecular mechanisms of metformin: a new perspective for treatment and prevention of diseases.

Amin Hasanvand.

  Metformin can suppress gluconeogenesis and reduce blood sugar by activating adenosine monophosphate-activated protein kinase (AMPK) and inducing small heterodimer partner (SHP) expression in the liver cells. The main mechanism of metformin's action is related to its activation of the AMPK enzyme and regulation of the energy balance. AMPK is a heterothermic serine/threonine kinase made of a catalytic alpha subunit and two subunits of beta and a gamma regulator. This enzyme can measure the intracellular ratio of AMP/ATP. If this ratio is high, the amino acid threonine 172 available in its alpha chain would be activated by the phosphorylated liver kinase B1 (LKB1), leading to AMPK activation. Several studies have indicated that apart from its significant role in the reduction of blood glucose level, metformin activates the AMPK enzyme that in turn has various efficient impacts on the regulation of various processes, including controlling inflammatory conditions, altering the differentiation pathway of immune and non-immune cell pathways, and the amelioration of various cancers, liver diseases, inflammatory bowel disease (IBD), kidney diseases, neurological disorders, etc. Metformin's activation of AMPK enables it to control inflammatory conditions, improve oxidative status, regulate the differentiation pathways of various cells, change the pathological process in various diseases, and finally have positive therapeutic effects on them. Due to the activation of AMPK and its role in regulating several subcellular signalling pathways, metformin can be effective in altering the cells' proliferation and differentiation pathways and eventually in the prevention and treatment of certain diseases.

Keywords:  AMPK; Diseases; Metformin

DOI:  https://doi.org/10.1007/s10787-022-00980-6
Animals (Basel). 2022 Apr 06. pii: 939. [Epub ahead of print]12(7):

FGF21 Reduces Lipid Accumulation in Bovine Hepatocytes by Enhancing Lipid Oxidation and Reducing Lipogenesis via AMPK Signaling.

Yezi Kong, Chenxu Zhao, Panpan Tan, Siqi Liu, Yan Huang, Fangyuan Zeng, Pingjun Ma, Yazhou Guo, Baoyu Zhao, Jianguo Wang.

  During the periparturient period, dairy cows suffer drastic metabolic stress because of plasma increased non-esterified fatty acids (NEFAs) that stem from a negative energy balance. Fibroblast growth factor 21 (FGF21) is a hepatokine that activates the AMP-activated protein kinase (AMPK) signaling pathway to maintain intracellular energy balance and tissue integrity via the promotion of catabolism and the inhibition of anabolic regulation. FGF21 treatment caused a 50% reduction in triglyceride (TG) content in liver in dairy cows. However, it is not clear whether FGF21 regulates lipid metabolism in bovine liver. The purpose of this study was to evaluate the influence of FGF21 on lipid metabolism via AMPK signaling in bovine hepatocytes. The hepatocytes isolated from calves were treated with different concentrations of FGF21 or co-treated with AMPK inhibitor (BML-275). Herein, the study showed that FGF21 significantly reduced TG content in a dose-response manner and promoted very-low-density lipoprotein (VLDL) secretion via an up-regulation of the proteins (ApoB 100, ApoE and MTTP) involved in VLDL secretion. Otherwise, the genes associated with lipid transport (LDLR and CD36) and lipid oxidation (PPARGC1A, ACOX1 and CPT1A), were up-regulated following FGF21 treatment. Moreover, FGF21 treatment inhibited lipogenesis via SREBF1, ACACA, FASN and ACLY inhibition. After being co-treated with the AMPK inhibitor, FGF21-induced changes were reversed in some genes. In conclusion, these results indicate that FGF21 adaptively regulates energy metabolism for a negative impact on lipogenesis, strengthens lipid oxidation, and inhibited lipid transportation via AMPK signaling in bovine hepatocytes. The present data suggest the possibility that FGF21 has potential value in alleviating perinatal metabolic diseases in dairy cows, and specific research in vivo should be studied in more detail.

Keywords:  AMPK pathway; bovine hepatocytes; dairy cows; fibroblast growth factor 21; lipid metabolism

DOI:  https://doi.org/10.3390/ani12070939
Front Pharmacol. 2022 ;13 815413

The Protective Effect of Pilose Antler Peptide on CUMS-Induced Depression Through AMPK/Sirt1/NF-κB/NLRP3-Mediated Pyroptosis.

Yue Hu, Min Zhao, Tong Zhao, Mingming Qi, Guangda Yao, Yu Dong.

  Background: Pilose antler peptide (PAP), prepared from the pilose antler of Cervus nippon Temminck, is widely used in traditional Chinese medicine (TCM) against various inflammatory disorders. TCM prescriptions containing pilose antler are often prescribed clinically to treat depression. However, the pharmacological mechanisms of how PAP, against inflammation, prevents and treats depression remain poorly understood. Methods: PAP was identified by de novo sequencing and database searching. Then, behavioral tests were conducted to investigate the effect of PAP on CUMS-exposed mice. In parallel, Nissl staining and Golgi-Cox staining were used for exploring the effect of PAP on neural cells and dendritic spine density. Additionally, the expression of key proteins of the AMPK/Sirt1/NF-κB/NLRP3 pathway was analyzed by Western blot. Finally, the CUMS procedure was conducted for 6 weeks. At the 5th week, PAP and fluoxetine (Flu) were intragastrically treated for 2 weeks. The silencing information regulator-related enzyme 1 (Sirt1) inhibitor EX-527 and the AMP-activated protein kinase (AMPK) inhibitor dorsomorphin were employed to investigate the effects of Sirt1 and AMPK on PAP-mediated depression. Results: PAP attenuated the behavior alteration caused by CUMS stimulation, decreased the number of neurons, and restored the dendritic spine density. PAP treatment effectively upregulated the expressions of p-AMPK and Sirt1 and suppressed the expressions of Ac-NF-κB, NLRP3, Ac-Caspase-1, GSDMD-N, Cleaved-IL-1β, and Cleaved-IL-18. Moreover, selectively inhibited Sirt1 and AMPK were able to compromise the therapeutic effect of PAP on depression. Conclusion: The present work indicated that PAP has a protective effect on CUMS-induced depression. In addition, AMPK and Sirt1 played critical roles in the PAP-relieved depression. PAP might be a potential therapeutic option for treating depression.

Keywords:  AMPK; CUMS; NF-κB; NLRP3; SIRT1; pilose antler peptide; pyroptosis

DOI:  https://doi.org/10.3389/fphar.2022.815413
J Biol Chem. 2022 Apr 09. pii: S0021-9258(22)00369-6. [Epub ahead of print] 101929

Biochemical purification uncovers mammalian sterile 3 (MST3) as a new protein kinase for multifunctional protein kinases AMPK and SIK3.

Yuxiang Liu, Tao V Wang, Yunfeng Cui, Shengxian Gao, Yi Rao.

The adenosine monophosphate activated protein kinase (AMPK) and AMPK- related kinase (ARK) salt inducible kinase (SIK3) regulate many important biological processes ranging from metabolism to sleep. Liver kinase B1 (LKB1) is known to phosphorylate and activate both AMPK and SIK3, but the existence of other upstream kinases was unclear. In this study, we detected LKB1-independent ARK phosphorylation activities in human embryonic kidney (HEK) cells as well as in mouse brains. Biochemical purification of this phosphorylation activity uncovered mammalian sterile twenty (MST) 3. We demonstrate that MST3 from HEK cells could phosphorylate AMPK and SIK3 in vivo. Additionally, recombinant MST3 expressed in and purified from Escherichia coli could directly phosphorylate AMPK and SIK3 in vitro. Moreover, four other members of the MST kinase family could also phosphorylate AMPK or SIK3. Our results have revealed new kinases able to phosphorylate and activate AMPK and SIK3.

DOI: https://doi.org/10.1016/j.jbc.2022.101929
Nutr Metab (Lond). 2022 Apr 15. 19(1): 29

L-theanine prevents progression of nonalcoholic hepatic steatosis by regulating hepatocyte lipid metabolic pathways via the CaMKKβ-AMPK signaling pathway.

Juanjuan Liang, Lili Gu, Xianli Liu, Xintong Yan, Xiaowen Bi, Xirui Fan, Jinyi Zhou, Shuai Lu, Lan Luo, Zhimin Yin.

   BACKGROUND: L-theanine, a non-protein amino acid was found principally in the green tea, has been previously shown to exhibit potent anti-obesity property and hepatoprotective effect. Herein, we investigated the effects of L-theanine on alleviating nonalcoholic hepatic steatosis in vitro and in vivo, and explored the underlying molecular mechanism.
METHODS: In vitro, HepG2 and AML12 cells were treated with 500 μM oleic acid (OA) or treated with OA accompanied by L-theanine. In vivo, C57BL/6J mice were fed with normal control diet (NCD), high-fat diet (HFD), or HFD along with L-theanine for 16 weeks. The levels of triglycerides (TG), accumulation of lipid droplets and the expression of genes related to hepatocyte lipid metabolic pathways were detected in vitro and in vivo.
RESULTS: Our data indicated that, in vivo, L-theanine significantly reduced body weight, hepatic steatosis, serum levels of alanine transaminase (ALT), aspartate transaminase (AST), TG and LDL cholesterol (LDL-C) in HFD-induced nonalcoholic fatty liver disease (NAFLD) mice. In vitro, L-theanine also significantly alleviated OA induced hepatocytes steatosis. Mechanic studies showed that L-theanine significantly inhibited the nucleus translocation of sterol regulatory element binding protein 1c (SREBP-1c) through AMPK-mTOR signaling pathway, thereby contributing to the reduction of fatty acid synthesis. We also identified that L-theanine enhanced fatty acid β-oxidation by increasing the expression of peroxisome proliferator-activated receptor α (PPARα) and carnitine palmitoyltransferase-1 A (CPT1A) through AMP-activated protein kinase (AMPK). Furthermore, our study indicated that L-theanine can active AMPK through its upstream kinase Calmodulin-dependent protein kinase kinase-β (CaMKKβ).
CONCLUSIONS: Taken together, our findings suggested that L-theanine alleviates nonalcoholic hepatic steatosis by regulating hepatocyte lipid metabolic pathways via the CaMKKβ-AMPK signaling pathway.

Keywords:  CaMKKβ; Hepatic steatosis; L-theanine; Lipid accumulation; SREBP-1c

DOI:  https://doi.org/10.1186/s12986-022-00664-6
Exp Biol Med (Maywood). 2022 Apr 11. 15353702221081546

Hypothermia preconditioning improves cardiac contractility after cardiopulmonary resuscitation through AMPK-activated mitophagy.

Yuanzheng Lu, Chenyu Zhang, Jie Chen, Qiuping Zou, Bo Li, Hongyan Wei, Mary P Chang, Xiaoxing Liao, Chunlin Hu.

  Hypothermia preconditioning (HPC) improves cardiac function after cardiac arrest, yet the mechanism is unclear. We hypothesized that HPC-activated adenosine monophosphate-activated protein kinase (AMPK) activity may be involved. Adult male Wistar rats were randomly divided into normothermia Control, HPC (cooling to 32-34°C for 30 min), and HPC + Compound C (Compound C 10 mg/kg was injected intraperitoneally 30 min before HPC group). The rats underwent 7 min of untreated ventricular fibrillation (VF) followed by cardiopulmonary resuscitation (CPR). Cardiac function and hemodynamic parameters were evaluated at 4 h after return of spontaneous circulation (ROSC). Survival status was determined 72 h after ROSC. Mechanistically, we further examined the AMPK-Unc-51 Like Autophagy Activating Kinase 1 (ULK1)-mitophagy pathway and autophagic flux in vivo and in vitro. Six of twelve rats in the Control group, 10 of 12 rats in the HPC group, and 7 of 12 rats in HPC + Compound C group were successfully resuscitated. The 72-h survival rates were 1 of 12 Control, 6 of 12 HPC, and 2 of 12 HPC + Compound C rats, respectively (P = 0.043). Rats in the HPC group demonstrated greater cardiac contractility and hemodynamic stability which were compromised by Compound C. Furthermore, HPC increased the protein levels of p-AMPKα and p-ULK1 and promoted the expression of mitochondrial autophagy-related genes. Compound C decreased the expression of mitochondrial autophagy-related genes and reduced autophagic flux. Consistent with the observations obtained in vivo, in vitro experiments in cultured neonatal rat cardiomyocytes (CMs) demonstrated that HPC attenuated simulated ischemia-reperfusion-induced CM death, accompanied by increased AMPK-ULK1-mitophagy pathway activity. These findings suggest that AMPK-ULK1-mitophagy pathway was activated by HPC and has a crucial role in cardioprotection during cardiac arrest. Manipulation of mitophagy by hypothermia may merit further investigation as a novel strategy to prevent cardiac ischemia-reperfusion injury.

Keywords:  AMPK-induced mitophagy; Cardiac arrest; cardiac dysfunction; hypothermia preconditioning

DOI:  https://doi.org/10.1177/15353702221081546
Cells. 2022 Mar 23. pii: 1076. [Epub ahead of print]11(7):

Stevioside Enhances the Anti-Adipogenic Effect and β-Oxidation by Activating AMPK in 3T3-L1 Cells and Epididymal Adipose Tissues of db/db Mice.

Miey Park, Hana Baek, Jin-Young Han, Hae-Jeung Lee.

  Stevioside, the primary sweetener in stevia, is a glycoside with numerous beneficial biological activities. However, its anti-adipogenic effects on tissue differentiation and adipose tissues remain to be thoroughly investigated. In this study, the anti-adipogenic effects of stevioside during the differentiation of 3T3-L1 cells and epididymal adipose tissues of db/db mice were investigated by measuring the lipid droplets stained with Oil Red O and an immunoblot assay. Immunoblot analysis revealed that stevioside downregulated the expression of peroxisome proliferator-activated receptor-gamma (PPARγ), sterol regulatory element-binding protein-1c (SREBP-1c), CCAAT/enhancer-binding protein alpha (C/EBPα), and fatty acid synthase (FAS). Additionally, the protein expression of carnitine palmitoyltransferase 1 (CPT1), silent mating type information regulation 2 homolog 1 (SIRT1), and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) increased following treatment with stevioside. Furthermore, stevioside increased the phosphorylation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), both in vitro and in vivo. The activity of AMPK in stevioside-treated 3T3-L1 cells was further confirmed using agonists and antagonists of AMPK signaling. Our data indicate that stevioside ameliorates anti-adipogenic effects and promotes β-oxidation in adipocytes by activating AMPK-mediated signaling. The results of this study clearly demonstrated the inhibitory effect of stevioside on the differentiation of adipocytes and the reduction of lipid accumulation in the epididymal adipose tissues of db/db mice.

Keywords:  3T3-L1 preadipocytes; adipogenesis; db/db mice; differentiation; stevioside

DOI:  https://doi.org/10.3390/cells11071076
Clin Res Hepatol Gastroenterol. 2022 Apr 12. pii: S2210-7401(22)00065-1. [Epub ahead of print] 101922

The mTORC1/AMPK pathway plays a role in the beneficial effects of semaglutide (GLP-1 receptor agonist) on the liver of obese mice.

Pedro Henrique Reis-Barbosa, Ilitch Aquino Marcondes-de-Castro, Thatiany de Souza Marinho, Marcia Barbosa Aguila, Carlos Alberto Mandarim-de-Lacerda.

   PURPOSE: - The liver regulates lipid metabolism. Decreasing mTOR (mechanistic target of rapamycin complex 1) and enhancing AMPK (AMP-activated protein kinase) help degrade hepatic diet-induced accumulated lipids. Therefore, the glucagon-like peptide type 1 receptor agonist (GLP-1) is indicated to treat obesity-related liver metabolic alterations. Then, we investigated the effects of semaglutide (recent GLP-1) by analyzing the liver mTORC1/AMPK pathway genes in obese mice.
BASIC PROCEDURES: - C57BL/6 male mice were separated into two groups and submitted for 16 weeks of obesity induction. Then they were treated for an additional four weeks with semaglutide (subcutaneous, 40 μg/kg once every three days). The groups formed were: C, control group; CS, control group plus semaglutide; HF, high-fat group; HFS, high-fat group plus semaglutide. Next, the livers were dissected, and rapidly fragments of all lobes were kept and frozen at -80° C for analysis (RT-qPCR).
MAIN FINDINGS: - Liver markers for the mTOR pathway associated with anabolism and lipogenesis de novo were increased in the HF group compared to the C group but comparatively attenuated by semaglutide. Also, liver markers for the AMPK pathway, which regulates chemical pathways involving the cell's primary energy source, were impaired in the HF group than in the C group but partly restored by semaglutide.
CONCLUSION: - the mTOR pathway was attenuated, and the insulin signaling and the AMPK pathway were enhanced by semaglutide, ameliorating the liver gene expressions related to the metabolism of obese mice. These findings are promising in delaying the progression of nonalcoholic fatty liver disease.

Keywords:  GLP-1 receptor agonist; Obesity; Type 2 diabetes; liver; molecular analysis

DOI:  https://doi.org/10.1016/j.clinre.2022.101922
J Biol Chem. 2022 Apr 09. pii: S0021-9258(22)00368-4. [Epub ahead of print] 101928

STE20 phosphorylation of AMPK related kinases revealed by biochemical purifications combined with genetics.

Yuxiang Liu, Tao V Wang, Yunfeng Cui, Chaoyi Li, Lifen Jiang, Yi Rao.

We have recently purified mammalian sterile twenty (MST) 3 as a kinase for the multifunctional kinases adenosine monophosphate activated protein kinase (AMPK)-related kinases (ARKs). However, unresolved questions from this study, such as remaining phosphorylation activities following deleting the MST3 gene from HEK cells and mice, led us to conclude that there were additional kinases for ARKs. Further purification recovered Ca2+/calmodulin-dependent protein kinase kinases (CaMKK) 1 and 2, and a third round of purification revealed mitogen-activated protein kinase kinase kinase kinase 5 (MAP4K5) as potential kinases of ARKs. We then demonstrated that MST3 and MAP4K5, both belonging to the STE20-like kinase family, could phosphorylate all 14 ARKs both in vivo and in vitro. Further examination of all 28 STE20 kinases detected variable phosphorylation activity on AMPK and the salt inducible kinase (SIK) 3. Taken together, our results have revealed novel relationships between STE20 kinases and ARKs, with potential physiological and pathological implications.

DOI: https://doi.org/10.1016/j.jbc.2022.101928
Circ Res. 2022 Apr 12. 101161CIRCRESAHA121320251

Epigenetic Upregulation of H19 and AMPK Inhibition Concurrently Contribute to S-Adenosylhomocysteine Hydrolase Deficiency-Promoted Atherosclerotic Calcification.

Xin Dai, Si Liu, Lokyu Cheng, Ting Huang, Honghui Guo, Dongliang Wang, Min Xia, Wenhua Ling, Yunjun Xiao.

   BACKGROUND: S-adenosylhomocysteine (SAH) is a risk factor of cardiovascular disease; inhibition of SAH hydrolase (SAHH) results in SAH accumulation and induces endothelial dysfunction and atherosclerosis. However, the effect and mechanism of SAHH in atherosclerotic calcification is still unclear. We aimed to explore the role and mechanism of SAHH in atherosclerotic calcification.
METHODS: The relationship between SAHH and atherosclerotic calcification was investigated in patients with coronary atherosclerotic calcification. Different in vivo genetic models were used to examine the effect of SAHH deficiency on atherosclerotic calcification. Human aortic and murine vascular smooth muscle cells (VSMCs) were cultured to explore the underlying mechanism of SAHH on osteoblastic differentiation of VSMCs.
RESULTS: The expression and activity of SAHH were decreased in calcified human coronary arteries and inversely associated with coronary atherosclerotic calcification severity, whereas plasma SAH and total homocysteine levels were positively associated with coronary atherosclerotic calcification severity. Heterozygote knockout of SAHH promoted atherosclerotic calcification. Specifically, VSMC-deficient but not endothelial cell-deficient or macrophage-deficient SAHH promoted atherosclerotic calcification. Mechanistically, SAHH deficiency accumulated SAH levels and induced H19-mediated Runx2 (runt-related transcription factor 2)-dependent osteoblastic differentiation of VSMCs by inhibiting DNMT3b (DNA methyltransferase 3 beta) and leading to hypomethylation of the H19 promoter. On the other hand, SAHH deficiency resulted in lower intracellular levels of adenosine and reduced AMPK (AMP-activated protein kinase) activation. Adenosine supplementation activated AMPK and abolished SAHH deficiency-induced expression of H19 and Runx2 and osteoblastic differentiation of VSMCs. Finally, AMPK activation by adenosine inhibited H19 expression by inducing Sirt1-mediated histone H3 hypoacetylation and DNMT3b-mediated hypermethylation of the H19 promoter in SAHH deficiency VSMCs.
CONCLUSIONS: We have confirmed a novel correlation between SAHH deficiency and atherosclerotic calcification and clarified a new mechanism that epigenetic upregulation of H19 and AMPK inhibition concurrently contribute to SAHH deficiency-promoted Runx2-dependent atherosclerotic calcification.

Keywords:  S-adenosylhomocysteine; epigenomics; histones; humans; mice

DOI:  https://doi.org/10.1161/CIRCRESAHA.121.320251
Arch Pharm (Weinheim). 2022 Apr 12. e2100465

Novel pyrazolo[3,4-b]pyridine derivatives: Synthesis, structure-activity relationship studies, and regulation of the AMPK/70S6K pathway.

Yating Guo, Xiaoding Jiang, Qi Chang, Zhihong Xiao, Zhuo Chen, Dejian Jiang, Gaoyun Hu, Qianbin Li.

  A series of novel pyrazolo[3,4-b]pyridine derivatives were designed, synthesized, and biologically evaluated for anti-lung cancer activity. Structure-activity relationship and AutoGPA models were constructed based on the in vitro antiproliferative potency of the compounds against a human lung adenocarcinoma cell line (A549). Compound 9d exhibits improved potency for A549 cell growth inhibition (3.06 ± 0.05 μM) compared with A-769662 (45.29 ± 2.14 μM). Compound 9d can elevate the phosphorylation levels of adenosine monophosphate-activated protein kinase (AMPK) and its substrate acetyl-CoA carboxylase and reduce the level of phosphorylated ribosomal S6 kinase (p-70S6K) at 1 μM, which is comparable to the activity of A-769662 at 20 μM. 9d induced G2/M cell cycle arrest, which was rescued when co-incubated with "Compound C," a potent AMPK inhibitor. Taken together, compound 9d showed potential anti-lung cancer activity via inducing cell cycle arrest by regulation of the AMPK/70S6K pathway in A549 cells, which could provide a new lead for the discovery of anti-lung cancer agents.

Keywords:  3D-QSAR; AMPK; lung cancer; pyrazolo[3,4-b]pyridine

DOI:  https://doi.org/10.1002/ardp.202100465
Cells. 2022 Mar 22. pii: 1067. [Epub ahead of print]11(7):

Psoralen Suppresses Lipid Deposition by Alleviating Insulin Resistance and Promoting Autophagy in Oleate-Induced L02 Cells.

Yuhao Wang, Yonglun Wang, Fang Li, Jie Zou, Xiaoqian Li, Mengxia Xu, Daojiang Yu, Yijia Ma, Wei Huang, Xiaodong Sun, Yuanyuan Zhang.

  Non-alcoholic fatty liver disease (NAFLD) held a high global prevalence in recent decades. Hepatic lipid deposition is the major characteristic of NAFLD. We aim to explore the mechanisms of psoralen on lipid deposition in NAFLD. The effects of psoralen on insulin resistance, lipid deposition, the expression and membrane translocation of glucose transporter type 4 (GLUT4), autophagy, and lipogenesis enzymes were determined on sodium oleate-induced L02 cells. Chloroquine and 3-MA were employed. The AMP-activated protein kinase alpha (AMPKα) was knocked down by siRNA. Psoralen alleviated insulin resistance in sodium oleate-induced L02 hepatocytes by upregulating the expression and membrane translocation of GLUT4. Psoralen inhibited lipid accumulation by decreasing the expression of key lipogenesis enzymes. Psoralen promotes autophagy and the autophagic flux to enhance lipolysis. Psoralen promoted the fusion of the autophagosome with the lysosome. Both chloroquine and 3-MA blocked the effects of psoralen on autophagy and lipid accumulation. The AMPKα deficiency attenuated the effects of psoralen on autophagy and lipid accumulation. Our study demonstrated that as an antioxidant, psoralen attenuates NAFLD by alleviating insulin resistance and promoting autophagy via AMPK, suggesting psoralen to be a promising candidate for NAFLD.

Keywords:  AMPK; autophagy; non-alcoholic fatty liver disease; psoralen

DOI:  https://doi.org/10.3390/cells11071067
Int Immunopharmacol. 2022 Apr 08. pii: S1567-5769(22)00194-1. [Epub ahead of print]108 108710

Maackiain protects against sepsis via activating AMPK/Nrf2/HO-1 pathway.

Xiaoxue Bai, Yingjie Zhu, Jing Jie, Dan Li, Lei Song, Jingjing Luo.

  Sepsis is a life-threatening medical condition caused by infection-triggered aberrant immune responses, leading to host tissue and organ injury. Despite advances in medical interventions, the mortality rate for septic shock remains high. Recent studies highlight the role of oxidative stress in the occurrence and development of sepsis, providing a potential therapeutic target for preventing sepsis-associated organ injury. In this study, we showed that Maackiain, a natural compound isolated from Sophora flavescens, exerted a protective role in a cecal ligation and puncture (CLP)-induced murine model of sepsis. Maackiain treatment reduced organ injury, and mitigated systematic inflammation and oxidative stress in septic mice. Maackiain also reduced the levels of inflammatory cytokines and reactive oxygen species (ROS) in RAW264.7 macrophage cells stimulated with lipopolysaccharide (LPS). We further demonstrated that Maackiain initiated activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway in RAW264.7 cells in an AMP-activated protein kinase (AMPK)-dependent way. Moreover, inhibition of AMPK/Nrf2 axis abrogated the anti-inflammatory and anti-oxidant effects of Maackiain both in vitro and in vivo. Collectively, our study indicates that Maackiain treatment inhibits inflammatory response and oxidative stress via activation of AMPK/Nrf2/HO-1 pathway, thus exerting a protective effect against sepsis, providing an alternative option for sepsis prevention.

Keywords:  Immune response; Infection; Inflammation; Macrophage; Organ; Oxidative stress

DOI:  https://doi.org/10.1016/j.intimp.2022.108710
Bioengineered. 2022 Apr;13(4): 9855-9871

Calcium-binding protein 39 overexpression promotes macrophages from 'M1' into 'M2' phenotype and improves chondrocyte damage in osteoarthritis by activating the AMP-activated protein kinase/sirtuin 1 axis.

Qiuliang Liu, Kai Pian, Zhen Tian, Haitao Duan, Qi Wang, Hui Zhang, Longyan Shi, Dongjian Song.

  Osteoarthritis (OA) is a degenerative joint disease that affects cartilage and its peripheral tissues. Up-regulation of Calcium-binding protein 39 (CAB39) has a significant protective effect on osteoblasts, but the role and related molecular mechanisms of CAB39 in OA have not yet been reported. CAB39 overexpression and knockdown models were set up in chondrocytes (ATDC5) and macrophages (RAW264.7). The OA cell model was induced in ATDC5 cells with IL-1β (10 ng/mL). Cell viability was tested by the cell counting kit-8 assay, apoptosis was checked by flow cytometry. Western blot was applied for checking the expression of MMP3, MMP13, Aggrecan, the AMPK/Sirt-1 pathway, apoptosis-related proteins (Bax, Bcl-2, and Caspase-3), and macrophage phenotypic markers (CD86, iNOS, CD206, and Arg1). An OA model was constructed in mice, and CAB39 overexpression plasmids were administered to the knee cavity of the OA model mice. As a result, CAB39 was down-regulated in IL-1β-treated chondrocytes and OA mice. Overexpressing CAB39 enhanced ATDC5 cell viability and choked IL-1β-mediated apoptosis. Overexpression of CAB39 boosted the polarization of macrophages from M1-phenotype into M2 phenotype. In addition, overexpressing CAB39 facilitated the AMPK/Sirt-1 pathway activation, and AMPK inhibitors reversed the protective effect of CAB39 overexpression on chondrocytes. Moreover, CAB39 exhibited anti-inflammatory effects in OA mice by activating the AMPK/Sirt-1 pathway. Collectively, overexpressing CAB39 heightened macrophages' M2 polarization and declined chondrocyte injury in OA by activating the AMPK/Sirt-1 pathway.Abbreviations AMPK: AMP-activated protein kinaseArg1: arginase 1Bax: Bcl-2-associated X proteinBcl-2: B-cell lymphoma-2CAB39: Calcium-binding protein 39CM: Conditioned mediumDMM: destabilization of the medial meniscusECM: extracellular matrixELISA: enzyme-linked immunosorbent assayFCM: Flow cytometryIL-1β: interleukin-1βIL-4: interleukin-4IL-6: interleukin-6IL-10: interleukin-10IFN - γ: Interferon-gammaIHC: ImmunohistochemistryiNOS: Inducible nitric oxide synthaseLKB1: liver kinase B1MMP3: Matrix metalloproteinase3MMP13:Matrix metalloproteinase13NF-κB: NF-kappaBOA: OsteoarthritisqRT-PCR: Quantitative reverse transcription-polymerase chain reactionRT: room temperatureSirt-1: sirtuin 1STRAD: STE20-related adaptor alphaWB: Western blot.

Keywords:  AMPK; CAB39; macrophages; osteoarthritis; sirt-1

DOI:  https://doi.org/10.1080/21655979.2022.2061289
Ecotoxicol Environ Saf. 2022 Apr 08. pii: S0147-6513(22)00301-3. [Epub ahead of print]236 113461

Metformin alleviates nickel-refining fumes-induced aerobic glycolysis via AMPK/GOLPH3 pathway in vitro and in vivo.

Tong Zhang, Yue Wang, Yangyang Chen, Ying Gao, Dan Zhang, Shuo Jin, Wenxue Yao, Lina Li, Shikuan Yang, Yonghui Wu.

  Nickel (Ni) compounds is recognized industrial carcinogen, which could increase the risk of lung cancer in Ni refineries workers. However, the underlying carcinogenic mechanism still remains to elucidate. Metformin has shown the anticancer properties through suppressing aerobic glycolysis. In the present study, we evaluated the effect of Ni-refining fumes exposure on aerobic glycolysis and the role of AMPK/GOLPH3, as well as how metformin alleviated nickel-induced aerobic glycolysis in vitro and vivo. Firstly, Beas-2B cells were exposed to different concentrations of Ni-refining fumes and pretreated with metformin (activation of AMPK), compound C (AMPK inhibitor) in vitro. Our findings indicated that Ni fumes expose evoked aerobic glycolysis by AMPK/GOLPH3, while metformin attenuated Ni particles-promoted GOLPH3-mediated aerobic glycolysis by p-AMPK expression increase. Then Mito-TEMPT (a mitochondria-targeted antioxidant) and lipopolysaccharide (LPS, ROS activator) were pretreated to affect ROS production in Beas-2B cells. Ni-induced ROS prevented AMPK activation. Moreover, C57BL/6 mice were exposed to 2 mg/kg Ni by non-exposed endotracheal instillation and metformin (100, 200 and 300 mg/kg) via oral gavage for 4 weeks. The effects of AMPK/GOLPH3 axis on Ni-induced aerobic glycolysis were assessed. The results indicated that metformin decreased the protein levels of GOLPH3, LDHA, HK2, MCT-4 and improved p-AMPK expression. Thus, our findings demonstrated metformin antagonized Ni-refining fumes-caused aerobic glycolysis via AMPK/GOLPH3.

Keywords:  AMPK; Aerobic glycolysis; GOLPH3; Metformin; Nickel-refining fumes

DOI:  https://doi.org/10.1016/j.ecoenv.2022.113461
Anal Cell Pathol (Amst). 2022 ;2022 8708202

Mesenchymal Stem Cells and their Derived Exosomes Promote Malignant Phenotype of Polyploid Non-Small-Cell Lung Cancer Cells through AMPK Signaling Pathway.

Lili Wang, Mingyue Ouyang, Sining Xing, Song Zhao, Shuo Liu, Lingyan Sun, Huiying Yu.

Chemotherapy is an important method for the treatment of non-small-cell lung cancer (NSCLC), but it can lead to side effects and polyploid cancer cells. The polyploid cancer cells can live and generate daughter cancer cells via budding. Mesenchymal stem cells (MSCs) are pluripotent stem cells with repair and regeneration functions and can resist tissue damage caused by tumor therapy. This study is aimed at investigating the effects of MSCs and their derived exosomes on the biological characteristics of polyploid NSCLC cells and the potential mechanisms. We found that MSC conditioned medium (CM), MSCs, and MSC-exosomes had no effect on cell proliferation of the polyploid A549 and H1299 cells. Compared with the control group, MSCs and MSC-exosomes significantly promoted epithelial mesenchymal transformation, cell migration, antiapoptosis, and autophagy in the polyploid A549 and H1299 by activating AMPK signaling pathway, but no significant changes were observed in MSC-CM treatment. These results revealed that MSCs and MSC-exosomes promoted malignant phenotype of polyploid NSCLC cells through the AMPK signaling pathway.

DOI: https://doi.org/10.1155/2022/8708202
Gen Physiol Biophys. 2022 Mar;41(2): 159-164

Polyphyllin I alleviates inflammatory injury in mice with gestational diabetes through AMPK pathway.

Yaoyao Cai, Fengfeng Xie, Haiou Wang, Qi Zhai, Feng Lin, Shishi Pan.

Our study aimed to detect the effects of polyphyllin I (PPI) on relieving gestational diabetes mellitus (GDM), and the possible mechanism. A mouse model of GDM was constructed. The effects of PPI on GDM mice were evaluated by detecting blood glucose, insulin level, glucose tolerance test, and insulin tolerance test. The inflammation response in GDM and GDM+PPI group were evaluated by enzyme-linked immunosorbent assay (ELISA). The effect of PPI on the offspring of GDM mice was analyzed. In addition, immunoblot assays were performed to investigate the effects of PPI on the AMPK pathway. We found that PPI improved diabetes-related symptoms and decreased serum inflammatory response in GDM mice. In addition, we also found that PPI reduced the tissue damage of GDM mice. We noticed that PPI alleviated inflammatory injury in GDM mice through targeting AMPK pathway. Our findings showed that PPI has the potential to be explored as the drug for GDM treatment.

DOI: https://doi.org/10.4149/gpb_2022006
Lupus Sci Med. 2022 Apr;pii: e000611. [Epub ahead of print]9(1):

Metformin improves renal injury of MRL/lpr lupus-prone mice via the AMPK/STAT3 pathway.

Xiao-Cui Chen, Dan Wu, Hong-Luan Wu, Hui-Yuan Li, Chen Yang, Hong-Yong Su, Ze-Jian Liu, Xiao-Rong Huang, Xing Lu, Li-Feng Huang, Shao-Ping Zhu, Qing-Jun Pan, Ning An, Hua-Feng Liu.

   OBJECTIVE: Lupus nephritis (LN) is a major complication and cause of death among patients with SLE. This research used in vivo and in vitro experiments to explore the therapeutic potential of metformin in kidney injury from LN-induced inflammation.
METHODS: In vivo study, 8-week-old MRL/MpJ-Faslpr/J (MRL/lpr) mice were randomly divided into two groups (n=12 each): daily administration of 0.3 mg/mL metformin in drinking water and control (water only). Body weight and urinary samples were measured biweekly. Mice were sacrificed after 8-week treatment to harvest serum, lymph nodes, spleen and kidneys. In vitro study, human kidney-2 (HK-2) cells were pretreated with 1 mM metformin for 1 hour and then stimulated with 20 µg/mL lipopolysaccharides (LPS) or 10 ng/mL tumour necrosis factor-α (TNF-α) for another 48 hours. Protein was collected for subsequent analysis.
RESULTS: We found that metformin administration improved renal function in MRL/lpr lupus-prone mice, measured by decreased urea nitrogen and urinary proteins. Metformin reduced immunoglobulin G and complement C3 deposition in glomeruli. The treatment also downregulated systemic and renal inflammation, as seen in decreased renal infiltration of F4/80-positive macrophages and reduced splenic and renal MCP-1 (monocyte chemoattractant protein-1) and TNF-α, and renal IL-1β (interleukin 1β) expression. Metformin administration decreased renal expression of necroptosis markers p-RIPK1 (phosphorylated receptor-interacting protein kinase 1) and p-MLKL, along with tubular injury marker KIM-1 (kidney injury molecule-1) in lupus mice. In addition, metformin alleviated the necroptosis of HK-2 cells stimulated by LPS and TNF-α, evidencing by a decrease in the expression of necroptosis markers p-RIPK1, p-RIPK3 and p-MLKL, and the inflammasome-related markers NLRP3 (NLR family pyrin domain containing 3), ASC (apoptosis-associated speck-like protein containing a CARD), caspase-1. Mechanistically, metformin treatment upregulated p-AMPK (phosphorylated AMP-activated protein kinase) and downregulated p-STAT3 (phosphorylated signal transducer and activator of transcription 3) expression in the kidneys. Moreover, AMPKα2 knockdown abolished the protective effects of metformin in vitro.
CONCLUSIONS: Metformin alleviated kidney injury in LN though suppressing renal necroptosis and inflammation via the AMPK/STAT3 pathway.

Keywords:  Lupus Erythematosus, Systemic; Lupus Nephritis; Therapeutics

DOI:  https://doi.org/10.1136/lupus-2021-000611
Phytomedicine. 2022 Mar 26. pii: S0944-7113(22)00159-3. [Epub ahead of print]100 154081

Capsaicin ameliorates intermittent high glucose-mediated endothelial senescence via the TRPV1/SIRT1 pathway.

Si-Lu Zhu, Mei-Ling Wang, Yue-Teng He, Shu-Wen Guo, Ting-Ting Li, Wei-Jie Peng, Dan Luo.

   BACKGROUND: Patients with diabetes have accelerated vascular aging when compared with healthy individuals. Hyperglycemia, especially intermittent high glucose (IHG), is the main cause of vascular endothelial senescence. Capsaicin, a major component of chili pepper is thought to contribute to cardiovascular protection by spicy food.
OBJECTIVE: To investigate the pathway related with the effects of capsaicin on endothelial cell senescence induced by IHG.
METHODS: HUVECs were exposed to IHG (5 mM or 33 mM glucose, alternating every 12 hours for 3 days) and treated with capsaicin at 0.3, 1 and 3 μM. To determine endothelial cell senescence, we examined the senescence-related β-galactosidase staining, cell cycle arrest, cell viability, as well as production of reactive oxygen species (ROS). To evaluate the involvement of TRPV1/[Ca2+]i/CaMKII/AMPK/SIRT1 pathway in anti- senescence effects of capsaicin, HUVECs were treated with CAPZ (a TRPV1 antagonist), BAPTA-AM (an intracellular calcium chelator), KN62 (a CaMKII antagonist), compound C (an AMPK inhibitor), or EX527 (a SIRT1 inhibitor). To knockdown TRPV1, HUVECs were transfected with shRNA lentivirus targeting TRPV1. The levels of SIRT1, p21, TRPV1, AMPK and phospho-AMPK were evaluated by western blotting.
RESULTS: IHG suppressed the levels of SIRT1 and enhanced endothelial senescence. Capsaicin upregulated SIRT1 expression and downregulated the senescence marker, p21, thereby protecting endothelial cells from IHG-induced senescence as indicated by relieved G0/G1 phase arrest, improved cell viabilities, and reduced counts of senescent cells and ROS production. Pre-treatment with CAPZ, BAPTA-AM, KN62 or compound C abrogated the anti-senescence effects of capsaicin. Capsaicin restored AMPK phosphorylation and IHG-inhibited TRPV1 expression. Moreover, TRPV1 silencing suppressed SIRT1 expression and abolished the anti-senescence effects of capsaicin.
CONCLUSION: Capsaicin elevates SIRT1 levels through TRPV1/[Ca2+]i/CaMKII/AMPK pathway and suppresses IHG-mediated endothelial cell senescence. This study provides initial evidence that capsaicin is a potential candidate for the prevention of vascular aging in diabetes.

Keywords:  Capsaicin; Endothelial senescence; Intermittent high glucose; SIRT1; TRPV1

DOI:  https://doi.org/10.1016/j.phymed.2022.154081
Neurochem Res. 2022 Apr 12.

Nandrolone Supplementation Promotes AMPK Activation and Divergent 18[FDG] PET Brain Connectivity in Adult and Aged Mice.

N R Strogulski, A Kopczynski, V G de Oliveira, R B Carteri, G Hansel, G T Venturin, S Greggio, J C DaCosta, M A De Bastiani, M S Rodolphi, L V Portela.

  Decreased anabolic androgen levels are followed by impaired brain energy support and sensing with loss of neural connectivity during physiological aging, providing a neurobiological basis for hormone supplementation. Here, we investigated whether nandrolone decanoate (ND) administration mediates hypothalamic AMPK activation and glucose metabolism, thus affecting metabolic connectivity in brain areas of adult and aged mice. Metabolic interconnected brain areas of rodents can be detected by positron emission tomography using 18FDG-mPET. Albino CF1 mice at 3 and 18 months of age were separated into 4 groups that received daily subcutaneous injections of either ND (15 mg/kg) or vehicle for 15 days. At the in vivo baseline and on the 14th day, brain 18FDG-microPET scans were performed. Hypothalamic pAMPKT172/AMPK protein levels were assessed, and basal mitochondrial respiratory states were evaluated in synaptosomes. A metabolic connectivity network between brain areas was estimated based on 18FDG uptake. We found that ND increased the pAMPKT172/AMPK ratio in both adult and aged mice but increased 18FDG uptake and mitochondrial basal respiration only in adult mice. Furthermore, ND triggered rearrangement in the metabolic connectivity of adult mice and aged mice compared to age-matched controls. Altogether, our findings suggest that ND promotes hypothalamic AMPK activation, and distinct glucose metabolism and metabolic connectivity rearrangements in the brains of adult and aged mice.

Keywords:  18FDG-PET; Aging; Anabolic-androgen steroids; Mitochondria; Nandrolone decanoate; Neural metabolic connectivity

DOI:  https://doi.org/10.1007/s11064-022-03592-2
Pharmacol Res. 2022 Apr 10. pii: S1043-6618(22)00164-5. [Epub ahead of print]179 106219

Combined Levo-tetrahydropalmatine and diphenyleneiodonium chloride enhances antitumor activity in hepatocellular carcinoma.

Xunzhe Yin, Jiaxin Zhang, Wenjing Zhao, Zuojia Liu, Jin Wang.

  Metabolic dysregulation is a hallmark of hepatocellular carcinoma (HCC). AMPK is a crucial hub of metabolic regulation during cancer progression. We show that phytochemical Levo-tetrahydropalmatine (THP) activates AMPK-dependent autophagy to downregulate the mitochondrial respiration and glycolysis. Consequently, THP significantly decreased cell viability in two HCC cell lines, BEL-7402 and SMMC-7721. Similarly, NOX4 inhibitor diphenyleneiodonium chloride (DPI) induces concomitant downregulation of the mitochondrial and glycolytic metabolism. In contrast to THP, cells are less sensitive to proliferation inhibition induced by DPI treatment as compared to THP treatment did. Combined treatment of THP and DPI was found to be more efficacious in killing cancer cells than either of the agents treated individually. Indeed, the co-operative effect by the THP-DPI combination improves the pro-apoptotic activity in response to the energy depletion as outlined by a drastic decrease in ATP levels. Therapeutic regime significantly reduced the tumor growth in mice. Importantly, this is realized without causing systemic toxicity to other organs. Collectively, our work shows that the combinatorial therapy of autophagy activator THP and NOX4 inhibitor DPI may be considered as a therapeutic avenue against HCC.

Keywords:  AMPK; Autophagy; Cancer metabolism; Chloroquine (PubChem CID: 2719); Dimethyl sulfoxide (PubChem CID: 679); Diphenyleneiodonium; Hepatocellular carcinoma; Levo-tetrahydropalmatine; Levo-tetrahydropalmatine (PubChem CID: 132535036); chloride (PubChem CID: 2733504)

DOI:  https://doi.org/10.1016/j.phrs.2022.106219
Diabetol Metab Syndr. 2022 Apr 13. 14(1): 53

Epigallocatechin-3-gallate ameliorates hepatic damages by relieve FGF21 resistance and promotion of FGF21-AMPK pathway in mice fed a high fat diet.

Yuanyuan Zhang, Ruili Yin, Jianan Lang, Ying Fu, Longyan Yang, Dong Zhao.

   BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is considered to be one of the most common chronic liver diseases across worldwide. Epigallocatechin-3-gallate (EGCG) derived from extract of green tea and is well known for beneficial effects on anti-oxidative, anti-inflammatory, and anti-tumor activity. The present study aimed to implore its underlying mechanism for protective effect of NAFLD.
METHODS: Mice were fed either high fat diet (HFD) or chow diet with or without EGCG treatment in HFD group, for up to 16 weeks. Histopathology, expression of lipid and glucose metabolism and lipogenesis-related gene expression were assessed. Primary mouse hepatocytes were treated with free fatty acids combined with different doses of EGCG for 48 h, expression of lipid and lipogenesis-related gene expression were assessed.
RESULTS: The results showed that EGCG attenuated HFD- and FFA-induced lipid accumulation in vivo and in vitro. EGCG can decrease the oxidative stress and promote Nrf2 level. Meanwhile EGCG alleviated FGF21 resistance and elevated FGFR/AMPK expression, which suggested an unrecognized mechanism of EGCG in ameliorating NAFLD.
CONCLUSIONS: EGCG attenuated hepatocytes damage and dysfunction in NAFLD by alleviating FGF21 resistance and improve FGFR/AMPK pathway, mitigating oxidative stress. Our studies verified that EGCG may become a promising drug to treat or relieve NAFLD.

Keywords:  EGCG; FGF21–AMPK; NAFLD

DOI:  https://doi.org/10.1186/s13098-022-00823-y
Metab Brain Dis. 2022 Apr 14.

Ligustilide ameliorates cognitive impairment via AMPK/SIRT1 pathway in vascular dementia rat.

Dong Peng, Han-Zi Qiao, Hong-Yu Tan, Yi-Xue Wang, Dan Luo, Li-Jun Qiao, Ye-Feng Cai, Shi-Jie Zhang, Qi Wang, Li Guan.

  Vascular dementia (VaD) is the second cause of dementia after Alzheimer's disease. Ligustilide (LIG) is one of the main active ingredients of traditional Chinese medicines, such as Angelica. Studies have reported that LIG could protect against VaD. However, the mechanism is still confused. In this study, we employed a bilateral common carotid artery occlusion rat model to study. LIG (20 or 40 mg/kg/day) and Nimodipine (20 mg/kg) were orally administered to the VaD rats for four weeks. Morris water maze test showed that LIG effectively ameliorated learning and memory impairment in VaD rats. LIG obviously reduced neuronal oxidative stress damage and the level of homocysteine in the brain of VaD rats. Western blot results showed that pro-apoptotic protein Bax and cleaved caspase 3 increased and anti-apoptotic protein Bcl-2 decreased in the hippocampi of VaD rats. But after LIG treatment, these changes were reversed. Moreover, Nissl staining result showed that LIG could reduce neuronal degeneration in VaD rats. Furthermore, LIG enhanced the expressions of P-AMPK and Sirtuin1(SIRT1) in VaD rats. In conclusion, these studies indicated that LIG could ameliorate cognitive impairment in VaD rats, which might be related to AMPK/SIRT1 pathway activation.

Keywords:  AMPK; Ligustilide; Neuronal degeneration; SIRT1; Vascular dementia

DOI:  https://doi.org/10.1007/s11011-022-00947-0
Int J Mol Sci. 2022 Apr 01. pii: 3927. [Epub ahead of print]23(7):

Structure-Activity Relationship of Synthetic Ginkgolic Acid Analogs for Treating Type 2 Diabetes by PTPN9 Inhibition.

Jinsoo Kim, Jinyoung Son, Dohee Ahn, Gibeom Nam, Xiaodi Zhao, Hyuna Park, Woojoo Jeong, Sang J Chung.

  Ginkgolic acid (C13:0) (GA), isolated from Ginkgo biloba, is a potential therapeutic agent for type 2 diabetes. A series of GA analogs were designed and synthesized for the evaluation of their structure-activity relationship with respect to their antidiabetic effects. Unlike GA, the synthetic analog 1e exhibited improved inhibitory activity against PTPN9 and significantly stimulated glucose uptake via AMPK phosphorylation in differentiated 3T3-L1 adipocytes and C2C12 myotubes; it also induced insulin-dependent AKT activation in C2C12 myotubes in a concentration-dependent manner. Docking simulation results showed that 1e had a better binding affinity through a unique hydrophobic interaction with a PTPN9 hydrophobic groove. Moreover, 1e ameliorated palmitate-induced insulin resistance in C2C12 cells. This study showed that 1e increases glucose uptake and suppresses palmitate-induced insulin resistance in C2C12 myotubes via PTPN9 inhibition; thus, it is a promising therapeutic candidate for treating type 2 diabetes.

Keywords:  AMPK; Akt; PTPN9 inhibitors; ginkgolic acid analogs; glucose uptake; insulin sensitivity

DOI:  https://doi.org/10.3390/ijms23073927
Int J Biol Sci. 2022 ;18(6): 2304-2316

Enhanced pentose phosphate pathway activity promotes pancreatic ductal adenocarcinoma progression via activating YAP/MMP1 axis under chronic acidosis.

Siyuan Chen, Bo Ning, Jinwen Song, Zihan Yang, Li Zhou, Zhiji Chen, Linhong Mao, Hongtao Liu, Qingliang Wang, Song He, Zhihang Zhou.

  Background: Acidic microenvironment is a common physiological phenomenon in tumors, and is closely related to cancer development, but the effects of acidosis on pancreatic adenocarcinoma (PDAC) remains to be elucidated. Methods: Metabonomic assay and transcriptomic microarray were used to detect the changes of metabolites and gene expression profile respectively in acidosis-adapted PDAC cells. Wound healing, transwell and in vivo assay were applied to evaluate cell migration and invasion capacity. CCK8 and colony formation assays were performed to determine cell proliferation. Results: The acidosis-adapted PDAC cells had stronger metastasis and proliferation ability compared with the control cells. Metabonomic analysis showed that acidosis-adapted PDAC cells had both increased glucose and decreased glycolysis, implying a shift to pentose phosphate pathway. The metabolic shift further led to the inactivation of AMPK by elevating ATP. Transcriptomic analysis revealed that the differentially expressed genes in acidosis-adapted cells were enriched in extracellular matrix modification and Hippo signaling. Besides, MMP1 was the most upregulated gene in acidosis-adapted cells, mediated by the YAP/TAZ pathway, but could be reduced by AMPK activator. Conclusion: The present study showed that metabolic reprogramming promotes proliferation and metastasis of acidosis-adapted PDAC cells by inhibiting AMPK/Hippo signaling, thus upregulating MMP1.

Keywords:  AMPK; Acidic microenvironment; Hippo signaling; MMP1; Metastasis; PDAC

DOI:  https://doi.org/10.7150/ijbs.69526
Biochem Biophys Res Commun. 2022 Apr 04. pii: S0006-291X(22)00525-3. [Epub ahead of print]608 142-148

Abietic acid alleviates endoplasmic reticulum stress and lipid accumulation in human primary hepatocytes through the AMPK/ORP150 signaling.

Tae Woo Jung, Ju-Cheol Jeong, Seung Yeon Park, Wonjun Cho, Heeseung Oh, Hyun Jung Lee, Ahmet Hacimuftuoglu, A M Abd El-Aty, Joon Seok Bang, Ji Hoon Jeong.

  Abietic acid (AA), the main component of pine resin that has been traditionally used as Asian medicine, has been reported to demonstrate anti-inflammatory activities. Despite this, little is known about the effects of AA on hepatic endoplasmic reticulum (ER) stress and lipid metabolism. This study investigated the impacts of AA on ER stress and steatosis in in vitro obesity models. We found that Treatment with AA reduced lipid deposition and lipogenesis-related proteins expression in human primary hepatocytes. Augmented expression of ER stress markers (phospho-eukaryotic initiation factor-2α (eIF2α) and C/EBP homologous protein (CHOP)) in palmitate-treated hepatocytes were reversed by AA treatment. Further, AA treatment increased the expression of phospho-AMPK and oxygen-regulated protein 150 (ORP150) in hepatocytes. siRNA-associated knockdown of AMPK or ORP150 expression reduced the effects of AA on not only hepatic ER stress but also lipogenesis and apoptosis. These results denote that AA attenuates lipid accumulation in hepatocytes in the presence of palmitate through the suppression of ER stress by AMPK/ORP150 signaling. AA could be a potential candidate for treating non-alcoholic fatty liver disease.

Keywords:  AMPK; Abietic acid; ER stress; NAFLD; ORP150

DOI:  https://doi.org/10.1016/j.bbrc.2022.04.010
Front Cell Dev Biol. 2022 ;10 836196

Defects of Nutrient Signaling and Autophagy in Neurodegeneration.

Jon Ondaro, Haizea Hernandez-Eguiazu, Maddi Garciandia-Arcelus, Raúl Loera-Valencia, Laura Rodriguez-Gómez, Andrés Jiménez-Zúñiga, Julen Goikolea, Patricia Rodriguez-Rodriguez, Javier Ruiz-Martinez, Fermín Moreno, Adolfo Lopez de Munain, Ian James Holt, Francisco Javier Gil-Bea, Gorka Gereñu.

  Neurons are post-mitotic cells that allocate huge amounts of energy to the synthesis of new organelles and molecules, neurotransmission and to the maintenance of redox homeostasis. In neurons, autophagy is not only crucial to ensure organelle renewal but it is also essential to balance nutritional needs through the mobilization of internal energy stores. A delicate crosstalk between the pathways that sense nutritional status of the cell and the autophagic processes to recycle organelles and macronutrients is fundamental to guarantee the proper functioning of the neuron in times of energy scarcity. This review provides a detailed overview of the pathways and processes involved in the balance of cellular energy mediated by autophagy, which when defective, precipitate the neurodegenerative cascade of Parkinson's disease, frontotemporal dementia, amyotrophic lateral sclerosis or Alzheimer's disease.

Keywords:  AMPK; autophagy; glucose metabolism; lipid metabolism; mTORC1 (mechanistic target of rapamycin complex 1); mitochondrial metabolism; neurodegenerative diseases; nutrient sensing pathways

DOI:  https://doi.org/10.3389/fcell.2022.836196
J Agric Food Chem. 2022 Apr 13.

Pterostilbene and Its Derivative 3'-Hydroxypterostilbene Ameliorated Nonalcoholic Fatty Liver Disease Through Synergistic Modulation of the Gut Microbiota and SIRT1/AMPK Signaling Pathway.

Hui-Yun Tsai, Yu-Yuan Shih, Yao-Tsung Yeh, Cheng-Hsieh Huang, Chorng-An Liao, Chun-Yi Hu, Kalyanam Nagabhushanam, Chi-Tang Ho, Yu-Kuo Chen.

  Nonalcoholic fatty liver disease (NAFLD) is a recent chronic liver disease common in many developed countries and is closely associated with metabolic syndrome, such as obesity and insulin resistance. The present study was performed to investigate the effects of pterostilbene (Pt) and its derivative 3'-hydroxypterostilbene (OHPt) on free fatty acids (FFA)-induced lipid accumulation in HepG2 cells and high-fat diet (HFD)-induced NAFLD in C57BL/6J mice. The results showed that Pt and OHPt significantly ameliorated FFA-induced steatosis in HepG2 cells and enhanced lipolysis through the upregulation of SIRT1/AMPK and insulin signaling pathways. In the in vivo study, Pt and OHPt treatment resulted in reduced hepatic lipid droplets accumulation. The data showed that Pt and OHPt upregulated the SIRT1/AMPK pathway and subsequently downregulated the protein expression of SREBP-1 to activate fatty acid (FA) β-oxidation to inhibit FA synthesis. Pt and OHPt administration activated the insulin signaling pathway and further ameliorated the insulin resistance and liver function in the HFD-fed mice. Furthermore, Pt and OHPt markedly increased the numbers of Oscillospira and decreased the numbers of Allobaculum, Phascolarctobacterium, and Staphylococcus compared with those in the HFD group. These robust results indicate that Pt and OHPt are able to possess potential health benefits in improving insulin resistance and hepatic steatosis by promoting healthy populations or abundances of considered vital microbiota. Besides, OHPt is more effective than Pt, which might have promising chemotherapeutic effects for future clinical application.

Keywords:  3′-hydroxypterostilbene; HepG2 cells; gut dysbiosis; nonalcoholic fatty liver disease; pterostilbene

DOI:  https://doi.org/10.1021/acs.jafc.2c00641
Gastroenterol Res Pract. 2022 ;2022 4745042

Explore the Mechanism of Astragalus mongholicus Bunge against Nonalcoholic Fatty Liver Disease Based on Network Pharmacology and Experimental Verification.

Lili Fu, Zhongming Wu, Yanjun Chu, Wenbin Chen, Ling Gao, Shumin Mu, Jiajun Zhao.

Objective: Astragalus mongholicus Bunge [Fabaceae] (AMB), a traditional Chinese medicine (TCM), has been widely used to treat liver diseases in the clinic. However, the efficacy and mechanism of AMB in the treatment of nonalcoholic fatty liver disease (NAFLD) remain unclear. The purpose of this study was to systematically investigate the active components and mechanisms of AMB against NAFLD based on network pharmacology, molecular docking, and experimental verification.
Methods: First, the bioactive components and relevant targets of AMB were screened from the Traditional Chinese Medicine Systematic Pharmacology (TCMSP) database, and NAFLD-related targets were obtained from the GeneCards database. Then, the AMB-NAFLD protein target interaction network was built by the STRING database. GO and KEGG pathway enrichment analyses were performed using the DAVID database. The component targets were visualized using Cytoscape software. Finally, molecular docking and experiments were used to verify the results of network pharmacological prediction.
Results: Network pharmacology predicted that quercetin may be the main active component in AMB, and the TNF and MAPK signaling pathways may be the key targets of AMB against NAFLD. Molecular docking validation results demonstrated that quercetin, as the main active component of AMB, had the highest binding affinity with TNF. Furthermore, quercetin played a distinct role in alleviating NAFLD through in vitro experiments. Quercetin upregulated the phosphorylation levels of AMPK and inhibited the expression of p-MAPK and TNF-α. In addition, we further discovered that quercetin could increase ACC phosphorylation and CPT1α expression in PA-induced HepG2 cells.
Conclusions: Our results indicated that quercetin, as the main active component in AMB, exerts an anti-NAFLD effect by regulating the AMPK/MAPK/TNF-α and AMPK/ACC/CPT1α signaling pathways to inhibit inflammation and alleviate lipid accumulation.

DOI: https://doi.org/10.1155/2022/4745042
J Agric Food Chem. 2022 Apr 14.

Ferrous Bisglycinate Supplementation Modulates Intestinal Antioxidant Capacity via the AMPK/FOXO Pathway and Reconstitutes Gut Microbiota and Bile Acid Profiles in Pigs.

Zhenglin Dong, Dongming Zhang, Xin Wu, Yulong Yin, Dan Wan.

  Multi-omics were applied to compare the risks and benefits of ferrous sulfate (FeSO4) and ferrous bisglycinate (FebisGly) in pigs in the current study. The FebisGly group showed reduced triglyceride (TG) and triglyceride/total cholesterol (TG/CHOL) values in the serum and reduced malondialdehyde (MDA) and increased glutathione (GSH) levels in the duodenum. Transcriptome analysis revealed that differentially expressed genes in the duodenum were enriched in oxidative phosphorylation, AMPK, and FOXO signaling pathways between FeSO4 and FebisGly groups. AMPK phosphorylation and FOXO3 protein expressions were significantly increased in the FebisGly group. Bacterial 16S rRNA gene sequence analysis revealed significantly reduced alpha diversity in the FeSO4 group and increased Firmicutes, reduced Bacteroidetes, and Proteobacteria abundances in the FebisGly group. Targeted metabolome revealed notably increased lithocholic acid (LCA), glycolithocholic acid (GLCA), hyodeoxycholic acid (HDCA), ursodeoxycholic acid (UDCA), and glycoursodeoxycholic acid (GUDCA) in the FebisGly group. RDA analysis indicated that Fusobacteria was positively correlated with TG and TG/high-density lipoprotein in the FeSO4 group while Christensenellaceae_R-7_group, Ruminococcaceae_UCG-002, and Ruminococcaceae_UCG-005 were positively correlated with UDCA and GLCA in the FebisGly group. According to the current study, FebisGly improves serum lipid metabolism, modulates intestinal antioxidant capacity via the AMPK/FOXO pathway, and reconstitutes gut microbiota and bile acid profiles in pigs.

Keywords:  bile acid; gut microbiota; iron deficiency; organic iron; transcriptome

DOI:  https://doi.org/10.1021/acs.jafc.2c00138
Life Sci. 2022 Apr 08. pii: S0024-3205(22)00230-2. [Epub ahead of print] 120530

Retraction notice to "Echinacoside improves diabetic liver injury by regulating the AMPK/SIRT1 signaling pathway in db/db mice" [Life Sci. 271 (2021) 119237].

Luo Yang, Xiang Zhang, Min Liao, Yarong Hao.

DOI: https://doi.org/10.1016/j.lfs.2022.120530
Metabolism. 2022 Apr 08. pii: S0026-0495(22)00078-6. [Epub ahead of print] 155200

Schisandrin B mitigates hepatic steatosis and promotes fatty acid oxidation by inducing autophagy through AMPK/mTOR signaling pathway.

Li-Shan Yan, Shuo-Feng Zhang, Gan Luo, Brian Chi-Yan Cheng, Chao Zhang, Yi-Wei Wang, Xin-Yu Qiu, Xiao-Hong Zhou, Qing-Gao Wang, Xue-Lan Song, Si-Yuan Pan, Yi Zhang.

   BACKGROUND: Schisandrin B (Sch B), which inhibits hepatic steatosis caused by non-alcoholic fatty liver disease (NAFLD), is one of the most active dibenzocyclooctadienes isolated from Schisandra chinensis (Turcz.) Baill with various pharmacological activities. In this study, the role of Sch B-induced autophagy in lipid-lowering activities of Sch B was examined and the underlying mechanisms were elucidated.
METHODS: Free fatty acid (FFA)-stimulated HepG2 cells and mouse primary hepatocytes (MPHs) and high-fat diet (HFD)-fed mice were used as NAFLD models. The role of Sch B-induced autophagy in lipid-lowering effects of Sch B was assessed using ATG5/TFEB-deficient cells and 3-methyladenine (3-MA)-treated hepatocytes and mice.
RESULTS: Sch B simultaneously active autophagy through AMPK/mTOR pathway and decreased the number of lipid droplets in FFA-treated HepG2 cells and MPHs. Additionally, siATG5/siTFEB transfection or 3-MA treatment mitigated Sch B-induced autophagy and activation of fatty acid oxidation (FAO) and ketogenesis in FFA-treated HepG2 cells and MPHs. Sch B markedly decreased hepatic lipid content and activated the autophagy through AMPK/mTOR pathway in HFD-fed mice. However, the activities of Sch B were suppressed upon 3-MA treatment. Sch B upregulated the expression of key enzymes involved in FAO and ketogenesis, which was mitigated upon 3-MA treatment. Moreover, changes in hepatic lipid components and amino acids may be related to the Sch B-induced autophagy pathway in vivo.
CONCLUSION: These results suggested that Sch B inhibited hepatic steatosis by activation of autophagy through AMPK/mTOR pathway. Our study provided novel insights into the hepatic lipophagic activity of Sch B and its potential application in the management of NAFLD.

Keywords:  Autophagy; Lipid metabolism; Non-alcoholic fatty liver disease; Schisandrin B

DOI:  https://doi.org/10.1016/j.metabol.2022.155200