bims-nurfca 2024-04-28 papers

bims-nurfca

Biomed News

on NRF2 and Cancer

Issue of 2024‒04‒28
sixteen papers selected by
Caner Geyik, Istinye University

Chelerythrine induces apoptosis and ferroptosis through Nrf2 in ovarian cancer cells.
Deferasirox Causes Leukaemia Cell Death through Nrf2-Induced Ferroptosis.
Nfe2l2/NRF2 deletion attenuates tumorigenesis and increases bacterial diversity in a mouse model of Lynch syndrome.
Brusatol hinders the progression of bladder cancer by Chac1/Nrf2/SLC7A11 pathway.
Prioritization of therapeutic targets for cancers using integrative multi-omics analysis.
Meningioma achieves malignancy and erastin-induced ferroptosis resistance through FOXM1-AURKA-NRF2 axis.
The emergence of tumor-initiating cells in an advanced hypopharyngeal tumor model exhibits enhanced angiogenesis and nuclear factor erythroid 2-related factor 2 associated antioxidant effects.
Biomarkers of NRF2 signalling: Current status and future challenges.
Revisiting Neuroblastoma: Nrf2, NF-κB and Phox2B as a Promising Network in Neuroblastoma.
Uncovering the Cardioprotective Potential of Diacerein in Doxorubicin Cardiotoxicity: Mitigating Ferritinophagy-Mediated Ferroptosis via Upregulating NRF2/SLC7A11/GPX4 Axis.
Ferroptosis and the ubiquitin-proteasome system: exploring treatment targets in cancer.
Cymensifin A: a promising pharmaceutical candidate to defeat lung cancer via cellular reactive oxygen species-mediated apoptosis.
[Microtubule-associated tumor suppressor 1 inhibits hemin-induced apoptosis of vascular endothelial cells via hemeoxygenase 1].
Protective Role of Dioscin against Doxorubicin-Induced Chronic Cardiotoxicity: Insights from Nrf2-GPX4 Axis-Mediated Cardiac Ferroptosis.
L-Glutamine Substantially Improves 5-Fluorouracil-Induced Intestinal Mucositis by Modulating Gut Microbiota and Maintaining the Integrity of the Gut Barrier in Mice.
Betaine ameliorates doxorubicin-induced cardiomyopathy by inhibiting oxidative stress, inflammation, and fibrosis through the modulation of AMPK/Nrf2/TGF-β expression.

Cell Mol Biol (Noisy-le-grand). 2024 Mar 31. 70(3): 174-181

Chelerythrine induces apoptosis and ferroptosis through Nrf2 in ovarian cancer cells.

Jia Zhou, Yuchen Wang, Yangxin Fu, Zhe Lin, He Lin, Guangfu Lv, Ning Kong, Guo Xin, Fang Zhou, Zhidong Qiu, Xiaowei Huang.

Ovarian cancer is a prevalent malignancy in the female reproductive system, representing a significantly fatal and incurable tumor. Chelerythrine (CHE), a natural benzopyridine alkaloid, has demonstrated a broad spectrum of anticancer activities. Nevertheless, the ovarian cancer inhibitory impact of CHE remains unclear. In this study, we investigated the cytotoxic mechanism and potential targets of CHE on in vitro cultures of A2780 and SKOV3 cells derived from ovarian cancer. Additionally, in vivo experiments were conducted to confirm the suppressive impact of CHE on tumor growth in nude mice. The findings revealed that CHE impeded the growth of A2780 and SKOV3 cells in a concentration-time-dependent manner and significantly suppressed the development of tumors in nude mice. CHE elevated the level of oxidative stress in tumor cells, prompted cell cycle halt in the S phase, and increased their mitochondrial membrane potential. Western blotting results demonstrated that CHE could modulate the expression of proteins associated with apoptotic and ferroptosis processes in A2780 and SKOV3 cells. Nrf2 was verified to be an upstream key target mediating the inhibitory impact of CHE on ovarian cancer cells. In summary, CHE exerts its anti-cancer effects on ovarian cancer by modulating Nrf2, inhibiting cellular proliferation, and promoting apoptosis and ferroptosis.

DOI: https://doi.org/10.14715/cmb/2024.70.3.26
Antioxidants (Basel). 2024 Mar 29. pii: 424. [Epub ahead of print]13(4):

Deferasirox Causes Leukaemia Cell Death through Nrf2-Induced Ferroptosis.

Wan-Yi Hsu, Li-Ting Wang, Pei-Chin Lin, Yu-Mei Liao, Shih-Hsien Hsu, Shyh-Shin Chiou.

  Acute lymphoblastic leukaemia (ALL) is the most prevalent cancer in children, and excessive iron buildup resulting from blood transfusions and chemotherapy potentially has a negative impact on treatment outcomes and prognosis in patients with ALL. Therefore, initiating early iron chelation therapy during ALL treatment is a logical approach. Ideally, the selected iron chelator should also possess anti-leukaemia properties. The aim of the present study was to explore the potential impact and underlying mechanism of deferasirox (DFX) in ALL therapy. This study proved that DFX, an iron chelator, is capable of inducing leukaemia cell death through ferroptosis, which is achievable by increasing the expression of acetylated nuclear factor erythroid 2-related factor 2 (NRF2). More specifically, NRF2 acetylation on Lys599 was facilitated by acetyltransferase-p300/CBP. These findings indicate that DFX could serve as a potent adjunctive medication for patients with ALL. Moreover, DFX may offer dual benefits in ALL treatment, functioning as both an iron chelator and NRF2-modulating agent. Further research and clinical trials are necessary to fully elucidate the therapeutic potential of DFX in patients with ALL and incorporate it into treatment protocols.

Keywords:  BCP-ALL; Nrf2; deferasirox

DOI:  https://doi.org/10.3390/antiox13040424
Cancer Prev Res (Phila). 2024 Apr 22.

Nfe2l2/NRF2 deletion attenuates tumorigenesis and increases bacterial diversity in a mouse model of Lynch syndrome.

Felix Haller, Kristine Jimenez, Maximilian Baumgartner, Michaela Lang, Anton Klotz, Manuela Jambrich, Georg Busslinger, Leonhard Müllauer, Vineeta Khare, Christoph Gasche.

Lynch syndrome (LS) is the most prevalent heritable form of colorectal cancer (CRC). Its early onset and high lifetime risk for CRC emphasize the necessity for effective chemoprevention. NFE2L2 (NRF2) is often considered a potential druggable target, and many chemopreventive compounds do induce NRF2. However, while NRF2 counteracts oxidative stress, it is also overexpressed in CRC and may promote tumorigenesis. Herein, we evaluated the role of NRF2 in prevention of LS-associated neoplasia. We found an increased levels of NRF2 in intestinal epithelia of mice with intestinal epithelial-specific Msh2 deletion (MSH2ΔIEC) as compared to C57BL/6 (wild type) mice, as well as an increase in downstream NRF2 targets Nqo1 and Gclc. Likewise, NRF2 levels were increased in human MSH2-deficient LS tumors compared to healthy controls. In silico analysis of a publicly accessible RNA-sequencing LS dataset also found an increase in downstream NRF2 targets. Upon crossing MSH2ΔIEC with Nrf2null mice (MSH2ΔIECNrf2null), we unexpectedly found reduced tumorigenesis in MSH2ΔIECNrf2null compared to MSH2ΔIEC after 40 weeks. This occurred despite an increase in oxidative damage in MSH2ΔIECNrf2null mice. Loss of NRF2 impaired proliferation as seen by Ki67 intestinal staining and in organoid cultures. This was accompanied by diminished WNT/β-catenin signaling. Apoptosis was unaffected. Microbial alpha-diversity increased over time with loss of NRF2 based upon 16S rRNA gene amplicon sequencing of murine fecal samples. Altogether, we show that NRF2 protein levels are increased in MSH2-deficiency and associated neoplasia, but loss of NRF2 attenuates tumorigenesis. Activation of NRF2 may not be a feasible strategy for chemoprevention in LS.

DOI: https://doi.org/10.1158/1940-6207.CAPR-23-0478
Exp Cell Res. 2024 Apr 23. pii: S0014-4827(24)00144-7. [Epub ahead of print] 114053

Brusatol hinders the progression of bladder cancer by Chac1/Nrf2/SLC7A11 pathway.

X I Yu, Z I Q I He, Q I N G H U A Wang, S H U A I Ke, H U A X I N Wang, Z H O N G Wang, S H E N G L A N Li.

  Bladder cancer is a common tumor that impacts the urinary system and marked by a significant fatality rate and an unfavorable prognosis. Promising antineoplastic properties are exhibited by brusatol, which is obtained from the dried ripe fruit of Brucea javanica. The present study aimed to evaluate the influence of brusatol on the progression of bladder cancer and uncover the molecular mechanism involved. We used Cell Counting Kit-8, colony formation and EdU assays to detect cell numbers, viability and proliferation. We used transwell migration assay to detect cell migration ability. The mechanism of brusatol inhibition of bladder cancer proliferation was studied by flow cytometry and western blotting. It was revealed that brusatol could reduce the viability and proliferation of T24 and 5637 cells. The transwell migration assay revealed that brusatol was able to attenuate the migration of T24 and 5637 cells. We found that treatment with brusatol increased the levels of reactive oxygen species, malondialdehyde and Fe2+, thereby further promoting ferroptosis in T24 and 5637 cells. In addition, treatment with RSL3 (an agonistor of ferroptosis) ferrostatin-1 (a selective inhibitor of ferroptosis) enhanced or reversed the brusatol-induced inhibition. In vivo, treatment with brusatol significantly suppressed the tumor growth in nude mice. Mechanistically, brusatol induced ferroptosis by upregulating the expression of ChaC glutathione-specific gamma-glutamylcyclotransferase (Chac1) and decreasing the expression of SLC7A11 and Nrf2 in T24 and 5637 cells. To summarize, the findings of this research demonstrated that brusatol hindered the growth of bladder cancer and triggered ferroptosis via the Chac1/Nrf2/SLC7A11 pathway.

Keywords:  ChaC glutathione-gpecific gamma-glutamylcyclotransferase; bladder cancer; brusatol; ferroptosis; nuclear factor erythroid 2-related factor 2

DOI:  https://doi.org/10.1016/j.yexcr.2024.114053
Hum Genomics. 2024 Apr 24. 18(1): 42

Prioritization of therapeutic targets for cancers using integrative multi-omics analysis.

Xin Jin, Yunyun Mei, Puyu Yang, Runze Huang, Haifeng Zhang, Yibin Wu, Miao Wang, Xigan He, Ziting Jiang, Weiping Zhu, Lu Wang.

  BACKGROUND: The integration of transcriptomic, proteomic, druggable genetic and metabolomic association studies facilitated a comprehensive investigation of molecular features and shared pathways for cancers' development and progression.METHODS: Comprehensive approaches consisting of transcriptome-wide association studies (TWAS), proteome-wide association studies (PWAS), summary-data-based Mendelian randomization (SMR) and MR were performed to identify genes significantly associated with cancers. The results identified in above analyzes were subsequently involved in phenotype scanning and enrichment analyzes to explore the possible health effects and shared pathways. Additionally, we also conducted MR analysis   to investigate metabolic pathways related to cancers.
RESULTS: Totally 24 genes (18 transcriptomic, 1 proteomic and 5 druggable genetic) showed significant associations with cancers risk. All genes identified in multiple methods were mainly enriched in nuclear factor erythroid 2-related factor 2 (NRF2) pathway. Additionally, biosynthesis of ubiquinol and urate were found to play an important role in gastrointestinal tumors.
CONCLUSIONS: A set of putatively causal genes and pathways relevant to cancers were identified in this study, shedding light on the shared biological processes for tumorigenesis and providing compelling genetic evidence to prioritize anti-cancer drugs development.

Keywords:  Cancers; Genome-wide association studies; Multi-omics; NRF2 pathway; Therapeutic targets

DOI:  https://doi.org/10.1186/s40246-024-00571-2
Redox Biol. 2024 Mar 28. pii: S2213-2317(24)00113-7. [Epub ahead of print]72 103137

Meningioma achieves malignancy and erastin-induced ferroptosis resistance through FOXM1-AURKA-NRF2 axis.

Yangfan Ye, Lei Xu, Liuchao Zhang, Pengzhan Zhao, Wanzhi Cai, Guoqiang Fu, Tian Wang, Zeqiang Tao, Wenqian Shi, Wei Gu, Jingming Hu, Guangyao Yuan, Yutian Wei, Ke Xu, Zhongyuan Bao, Honglu Chao, Ning Liu, Lin Zhao, Yiming Tu, Jing Ji.

  The oncogene Aurora kinase A (AURKA) has been implicated in various tumor, yet its role in meningioma remains unexplored. Recent studies have suggested a potential link between AURKA and ferroptosis, although the underlying mechanisms are unclear. This study presented evidence of AURKA upregulation in high grade meningioma and its ability to enhance malignant characteristics. We identified AURKA as a suppressor of erastin-induced ferroptosis in meningioma. Mechanistically, AURKA directly interacted with and phosphorylated kelch-like ECH-associated protein 1 (KEAP1), thereby activating nuclear factor erythroid 2 related factor 2 (NFE2L2/NRF2) and target genes transcription. Additionally, forkhead box protein M1 (FOXM1) facilitated the transcription of AURKA. Suppression of AURKA, in conjunction with erastin, yields significant enhancements in the prognosis of a murine model of meningioma. Our study elucidates an unidentified mechanism by which AURKA governs ferroptosis, and strongly suggests that the combination of AURKA inhibition and ferroptosis-inducing agents could potentially provide therapeutic benefits for meningioma treatment.

Keywords:  AURKA; Ferroptosis; Meningioma; NRF2; Protein kinase

DOI:  https://doi.org/10.1016/j.redox.2024.103137
Antioxid Redox Signal. 2024 Apr 25.

The emergence of tumor-initiating cells in an advanced hypopharyngeal tumor model exhibits enhanced angiogenesis and nuclear factor erythroid 2-related factor 2 associated antioxidant effects.

Min-Ying Lin, Chung-Yih Wang, Yang-Hsiang Chan, Shih-Po Su, Huihua Kenny Chiang, Muh-Hwa Yang, Yi-Jang Lee.

Hypopharyngeal cancer (HPC) is associated with the worst prognosis of all head and neck cancers and is typically identified in an advanced stage at the time of diagnosis. While oxidative stress might contribute to the onset of HPC in patients using tobacco or alcohol, the extent of this influence and the characteristics of HPC cells in advanced stage remain to be investigated. In this study, we explored whether HPC cells survived from necrotic xenograft tumors at late stage would display increased tumor resistance along with altered tolerance to oxidative stress. The remnant living HPC cells isolated from a late-stage xenograft tumor, named FaDu Ex-vivo cells showed stronger chemo- and radio-resistance, tumorigenesis, and invasiveness compared to parental FaDu cells. FaDu Ex-vivo cells also displayed increased angiogenic ability after re-transplantation to mice visualized by in vivo near infrared-II (NIR-II) fluorescence imaging modality. Moreover, FaDu Ex-vivo cells exhibited significant tumor-initiating cells (TICs) related properties accompanied by a reduction of the level of reactive oxygen species (ROS), which was associated with up-regulation of transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Interestingly, inhibition of Nrf2 by the RNA interference and the chemical inhibitor could reduce TICs related properties of FaDu Ex-vivo cells. Oxidative stress potentially initiates HPC, but elevation of Nrf2-associated antioxidant mechanisms would be essential to mitigate this effect for promoting and sustaining the stemness of HPC at the advanced stage. Current data suggest that the antioxidant potency of advanced HPC would be a therapeutic target for the design of adjuvant treatm.

DOI: https://doi.org/10.1089/ars.2023.0310
Redox Biol. 2024 Mar 30. pii: S2213-2317(24)00110-1. [Epub ahead of print]72 103134

Biomarkers of NRF2 signalling: Current status and future challenges.

Christina Morgenstern, Isabel Lastres-Becker, Birsen Can Demirdöğen, Vera Marisa Costa, Andreas Daiber, Roberta Foresti, Roberto Motterlini, Sibel Kalyoncu, Burak I Arioz, Sermin Genc, Monika Jakubowska, Ioannis P Trougakos, Aleksandra Piechota-Polanczyk, Michel Mickael, Marlene Santos, Thomas W Kensler, Antonio Cuadrado, Ian M Copple.

  The cytoprotective transcription factor NRF2 regulates the expression of several hundred genes in mammalian cells and is a promising therapeutic target in a number of diseases associated with oxidative stress and inflammation. Hence, an ability to monitor basal and inducible NRF2 signalling is vital for mechanistic understanding in translational studies. Due to some caveats related to the direct measurement of NRF2 levels, the modulation of NRF2 activity is typically determined by measuring changes in the expression of one or more of its target genes and/or the associated protein products. However, there is a lack of consensus regarding the most relevant set of these genes/proteins that best represents NRF2 activity across cell types and species. We present the findings of a comprehensive literature search that according to stringent criteria identifies GCLC, GCLM, HMOX1, NQO1, SRXN1 and TXNRD1 as a robust panel of markers that are directly regulated by NRF2 in multiple cell and tissue types. We assess the relevance of these markers in clinically accessible biofluids and highlight future challenges in the development and use of NRF2 biomarkers in humans.

Keywords:  Biomarker; NRF2; Oxidative stress response; Target genes; Transcription factor

DOI:  https://doi.org/10.1016/j.redox.2024.103134
Curr Issues Mol Biol. 2024 Apr 06. 46(4): 3193-3208

Revisiting Neuroblastoma: Nrf2, NF-κB and Phox2B as a Promising Network in Neuroblastoma.

Sara Peggion, Safiullah Najem, Jan Philipp Kolman, Konrad Reinshagen, Laia Pagerols Raluy.

  Neuroblastoma is the most common solid extracranial tumor during childhood; it displays extraordinary heterogeneous clinical courses, from spontaneous regression to poor outcome in high-risk patients due to aggressive growth, metastasizing, and treatment resistance. Therefore, the identification and detailed analysis of promising tumorigenic molecular mechanisms are inevitable. This review highlights the abnormal regulation of NF-κB, Nrf2, and Phox2B as well as their interactions among each other in neuroblastoma. NF-κB and Nrf2 play a key role in antioxidant responses, anti-inflammatory regulation and tumor chemoresistance. Recent studies revealed a regulation of NF-κB by means of the Nrf2/antioxidant response element (ARE) system. On the other hand, Phox2B contributes to the differentiation of immature sympathetic nervous system stem cells: this transcription factor regulates the expression of RET, thereby facilitating cell survival and proliferation. As observed in other tumors, we presume striking interactions between NF-κB, Nrf2, and Phox2B, which might constitute an important crosstalk triangle, whose decompensation may trigger a more aggressive phenotype. Consequently, these transcription factors could be a promising target for novel therapeutic approaches and hence, further investigation on their regulation in neuroblastoma shall be reinforced.

Keywords:  NF-κB; Nrf2; Phox2B; genetic alterations; neuroblastoma; signaling network

DOI:  https://doi.org/10.3390/cimb46040200
Antioxidants (Basel). 2024 Apr 20. pii: 493. [Epub ahead of print]13(4):

Uncovering the Cardioprotective Potential of Diacerein in Doxorubicin Cardiotoxicity: Mitigating Ferritinophagy-Mediated Ferroptosis via Upregulating NRF2/SLC7A11/GPX4 Axis.

Rehab M El-Gohary, Asmaa H Okasha, Alaa H Abd El-Azeem, Muhammad T Abdel Ghafar, Sarah Ibrahim, Islam I Hegab, Eman E Farghal, Soha Abdel Fattah Shalaby, Ola A Elshora, Aisha E ElMehy, Amany Nagy Barakat, Basma Saed Amer, Fatma G Sobeeh, Gehan H AboEl-Magd, Asmaa A Ghalwash.

  Doxorubicin (DOX)-induced cardiotoxicity (DIC) is a life-threatening clinical issue with limited preventive approaches, posing a substantial challenge to cancer survivors. The anthraquinone diacerein (DCN) exhibits significant anti-inflammatory, anti-proliferative, and antioxidant actions. Its beneficial effects on DIC have yet to be clarified. Therefore, this study investigated DCN's cardioprotective potency and its conceivable molecular targets against DIC. Twenty-eight Wister rats were assigned to CON, DOX, DCN-L/DOX, and DCN-H/DOX groups. Serum cardiac damage indices, iron assay, oxidative stress, inflammation, endoplasmic reticulum (ER) stress, apoptosis, ferritinophagy, and ferroptosis-related biomarkers were estimated. Nuclear factor E2-related factor 2 (NRF2) DNA-binding activity and phospho-p53 immunoreactivity were assessed. DCN administration effectively ameliorated DOX-induced cardiac cytomorphological abnormalities. Additionally, DCN profoundly combated the DOX-induced labile iron pool expansion alongside its consequent lethal lipid peroxide overproduction, whereas it counteracted ferritinophagy and enhanced iron storage. Indeed, DCN valuably reinforced the cardiomyocytes' resistance to ferroptosis, mainly by restoring the NRF2/solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) signaling axis. Furthermore, DCN abrogated the cardiac oxidative damage, inflammatory response, ER stress, and cardiomyocyte apoptosis elicited by DOX. In conclusion, for the first time, our findings validated DCN's cardioprotective potency against DIC based on its antioxidant, anti-inflammatory, anti-ferroptotic, and anti-apoptotic imprint, chiefly mediated by the NRF2/SLC7A11/GPX4 axis. Accordingly, DCN could represent a promising therapeutic avenue for patients under DOX-dependent chemotherapy.

Keywords:  diacerein; doxorubicin cardiotoxicity; ferritin heavy chain polypeptide 1; ferroptosis; iron; nuclear factor E2-related factor 2/solute carrier family 7 member 11/ glutathione peroxidase 4 axis; nuclear receptor coactivator 4-dependent ferritinophagy; oxidative stress

DOI:  https://doi.org/10.3390/antiox13040493
Front Pharmacol. 2024 ;15 1383203

Ferroptosis and the ubiquitin-proteasome system: exploring treatment targets in cancer.

Muhammad Azhar Ud Din, Yan Lin, Naijian Wang, Bo Wang, Fei Mao.

  Ferroptosis is an emerging mode of programmed cell death fueled by iron buildup and lipid peroxidation. Recent evidence points to the function of ferroptosis in the aetiology and development of cancer and other disorders. Consequently, harnessing iron death for disease treatment has diverted the interest of the researchers in the field of basic and clinical research. The ubiquitin-proteasome system (UPS) represents a primary protein degradation pathway in eukaryotes. It involves labelling proteins to be degraded by ubiquitin (Ub), followed by recognition and degradation by the proteasome. Dysfunction of the UPS can contribute to diverse pathological processes, emphasizing the importance of maintaining organismal homeostasis. The regulation of protein stability is a critical component of the intricate molecular mechanism underlying iron death. Moreover, the intricate involvement of the UPS in regulating iron death-related molecules and signaling pathways, providing valuable insights for targeted treatment strategies. Besides, it highlights the potential of ferroptosis as a promising target for cancer therapy, emphasizing the combination between ferroptosis and the UPS. The molecular mechanisms underlying ferroptosis, including key regulators such as glutathione peroxidase 4 (GPX4), cysteine/glutamate transporter (system XC-), and iron metabolism, are thoroughly examined, alongside the role of the UPS in modulating the abundance and activity of crucial proteins for ferroptotic cell death, such as GPX4, and nuclear factor erythroid 2-related factor 2 (NRF2). As a pivotal regulatory system for macromolecular homeostasis, the UPS substantially impacts ferroptosis by directly or indirectly modulating iron death-related molecules or associated signaling pathways. This review explores the involvement of the UPS in regulating iron death-related molecules and signaling pathways, providing valuable insights for the targeted treatment of diseases associated with ferroptosis.

Keywords:  cancer; degradation; ferroptosis; treatment; ubiquitin-proteasome pathway

DOI:  https://doi.org/10.3389/fphar.2024.1383203
Front Pharmacol. 2024 ;15 1361085

Cymensifin A: a promising pharmaceutical candidate to defeat lung cancer via cellular reactive oxygen species-mediated apoptosis.

Bruno Cesar Costa Soares, Hnin Ei Ei Khine, Boonchoo Sritularak, Pithi Chanvorachote, Rosa Alduina, Rungroch Sungthong, Chatchai Chaotham.

  Background: The upgrade of natural products for cancer treatment is essential since current anticancer drugs still pose severe side effects. Cymensifin A (Cym A) isolated from an orchid Cymbidium ensifolium has shown its potential to induce the death of several cancer cells; however, its underlying molecular mechanisms are hitherto unknown. Methods: Here, we conducted a set of in vitro preliminary tests to assess the cytotoxic effects of Cym A on non-small-cell lung cancer (NSCLC) cells (A549, H23, H292, and H460). A flow cytometry system and Western blot analyses were employed to unveil molecular mechanisms underlying cancer cell apoptosis caused by Cym A. Results: Cym A at 25-50 μM caused the death of all NSCLC cells tested, and its cytotoxicity was comparable to cisplatin, a currently used anticancer drug. The compound induced apoptosis of all NSCLC cells in a dose-dependent manner (5-50 μM), proven by flow cytometry, but H460 cells showed more resistance compared to other cells tested. Cym A-treated H460 cells demonstrated increased reactive oxygen species (ROS) and downregulated antioxidants (catalase, superoxide dismutase, and thioredoxin). The compound also upregulated the tumor suppressor P53 and the pro-apoptotic protein BAX but downregulated pro-survival proteins (BCL-2 and MCL-1) and deactivated survival signals (AKT and ERK) in H460 cells. Cym A was proven to trigger cellular ROS formation, but P53 and BAX were 2-fold more activated by Cym A compared to those treated with hydrogen peroxide. Our findings also supported that Cym A exerted its roles in the downregulation of nuclear factor erythroid 2-related factor 2 (a regulator of cellular antioxidant activity) and the increased levels of cleaved poly (ADP-ribose) polymerase (PARP) and cleaved caspase 3/7 during apoptosis. Conclusion: We propose that Cym A induces lung cancer cell death via ROS-mediated apoptosis, while the modulation of cellular ROS/antioxidant activity, the upregulation of P53 and BAX, the downregulation or deactivation of BCL-2, MCL-1, AKT, and ERK, and the increased cleavage of PARP and caspase 3/7, were the elucidated underlying molecular mechanisms of this phytochemical. The compound can be a promising candidate for future anticancer drug development.

Keywords:  Cymensifin A; DNA damage; ROS; apoptosis; lung cancer; mitochondrial outer membrane permeabilization; orchid

DOI:  https://doi.org/10.3389/fphar.2024.1361085
Sheng Li Xue Bao. 2024 Apr 25. 76(2): 215-223

[Microtubule-associated tumor suppressor 1 inhibits hemin-induced apoptosis of vascular endothelial cells via hemeoxygenase 1].

Sheng-Yun Wu, Ke-Ru Cheng, Yan-Yun Zhou, Yin-Fang Wang.

This study aimed to investigate the effects of microtubule associated tumor suppressor 1 (MTUS1) on hemeoxygenase 1 (HMOX1) expression and hemin-induced apoptosis of vascular endothelial cells and its regulatory mechanism. RNA sequencing, RT-qPCR and Western blot were used to assess altered genes of hemin binding proteins, the expression of cAMP response element-binding protein (CREB) and nuclear respiratory factor 2 (NRF2), hemin-induced HMOX1 expression in MTUS1 knockdown human umbilical vein endothelial cells (HUVEC), and the effect of overexpression of CREB and NRF2 on HMOX1 expression in MTUS1 knockdown 293T cells. The effect of MTUS1 or HMOX1 knockdown on hemin-induced apoptosis in HUVEC, and the overexpression of NRF2 on hemin-induced apoptosis in MTUS1 knockdown 293T cells were assayed with CCK8 and Western blot. The results showed that MTUS1 was knocked down significantly in HUVEC by siRNA (P < 0.01), accompanied by decreased HMOX1 expression (P < 0.01). The increased HMOX1 expression induced by hemin was also inhibited by MTUS1 knockdown (P < 0.01). And the apoptosis of HUVEC induced by hemin was amplified by MTUS1 or HMOX1 knockdown (P < 0.01). Moreover the expression of CREB and NRF2 were both inhibited by MTUS1 knockdown in HUVEC (P < 0.01). The decreased HMOX1 regulated by MTUS1 knockdown could be rescued partly by overexpression of NRF2 (P < 0.01), however, not by overexpression of CREB. And the MTUS1 knockdown mediated decreased 293T cells viability induced by hemin could be partly rescued by NRF2 overexpression (P < 0.01). These results suggest that MTUS1 can inhibit hemin-induced apoptosis of HUVEC, and the mechanism maybe related to MTUS1/NRF2/HMOX1 pathway.
Biomolecules. 2024 Mar 30. pii: 422. [Epub ahead of print]14(4):

Protective Role of Dioscin against Doxorubicin-Induced Chronic Cardiotoxicity: Insights from Nrf2-GPX4 Axis-Mediated Cardiac Ferroptosis.

Jia Liu, Honglin Liu, Liangyan Deng, Tao Wang, Luyao Li, Yuanyuan Chen, Liping Qu, Wenjun Zou.

  Recent evidence suggests that ferroptosis, an iron-facilitated cell death with excessive lipid peroxidation, is a critical mechanism underlying doxorubicin (DOX)-induced cardiotoxicity (DIC). Although dioscin has been reported to improve acute DIC, direct evidence is lacking to clarify the role of dioscin in chronic DIC and its potential mechanism in cardiac ferroptosis. In this study, we used chronic DIC rat models and H9c2 cells to investigate the potential of dioscin to mitigate DIC by inhibiting ferroptosis. Our results suggest that dioscin significantly improves chronic DIC-induced cardiac dysfunction. Meanwhile, it significantly inhibited DOX-induced ferroptosis by reducing Fe2+ and lipid peroxidation accumulation, maintaining mitochondrial integrity, increasing glutathione peroxidase 4 (GPX4) expression, and decreasing acyl-CoA synthetase long-chain family 4 (ACSL4) expression. Through transcriptomic analysis and subsequent validation, we found that the anti-ferroptotic effects of dioscin are achieved by regulating the nuclear factor-erythroid 2-related factor 2 (Nrf2)/GPX4 axis and Nrf2 downstream iron metabolism genes. Dioscin further downregulates nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) and upregulates expression of frataxin (FXN) and ATP-binding cassette B8 (ABCB8) to limit mitochondrial Fe2+ and lipid peroxide accumulation. However, Nrf2 inhibition diminishes the anti-ferroptotic effects of dioscin, leading to decreased GPX4 expression and increased lipid peroxidation. This study is a compelling demonstration that dioscin can effectively reduce DIC by inhibiting ferroptosis, which is dependent on the Nrf2/GPX4 pathway modulation.

Keywords:  Nrf2/GPX4 signaling pathway; chronic cardiotoxicity; dioscin; doxorubicin; ferroptosis

DOI:  https://doi.org/10.3390/biom14040422
Mol Nutr Food Res. 2024 Apr 24. e2300704

L-Glutamine Substantially Improves 5-Fluorouracil-Induced Intestinal Mucositis by Modulating Gut Microbiota and Maintaining the Integrity of the Gut Barrier in Mice.

Ya-Ru Kuo, Cheng-Hung Lin, Wei-Sheng Lin, Min-Hsiung Pan.

  SCOPE: This study investigates the potential of glutamine to mitigate intestinal mucositis and dysbiosis caused by the chemotherapeutic agent 5-fluorouracil (5-FU).METHODS AND RESULTS: Over twelve days, Institute of Cancer Research (ICR) mice are given low (0.5 mg kg-1) or high (2 mg kg-1) doses of L-Glutamine daily, with 5-FU (50 mg kg-1) administered between days six and nine. Mice receiving only 5-FU exhibited weight loss, diarrhea, abnormal cell growth, and colonic inflammation, correlated with decreased mucin proteins, increased endotoxins, reduced fecal short-chain fatty acids, and altered gut microbiota. Glutamine supplementation counteracted these effects by inhibiting the Toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB) pathway, modulating nuclear factor erythroid 2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) oxidative stress proteins, and increasing mammalian target of rapamycin (mTOR) levels, thereby enhancing microbial diversity and protecting intestinal mucosa.
CONCLUSIONS: These findings underscore glutamine's potential in preventing 5-FU-induced mucositis by modulating gut microbiota and inflammation pathways.

Keywords:  5‐fluorouracil; glutamine; intestinal mucositis; microbiota

DOI:  https://doi.org/10.1002/mnfr.202300704
Environ Toxicol. 2024 Apr 23.

Betaine ameliorates doxorubicin-induced cardiomyopathy by inhibiting oxidative stress, inflammation, and fibrosis through the modulation of AMPK/Nrf2/TGF-β expression.

Sumeet Kumar Singh, Poonam Yadav, Dhaneshvaree Patel, Sampat Singh Tanwar, Abhishek Sherawat, Amit Khurana, Jasvinder Singh Bhatti, Umashanker Navik.

  Doxorubicin (DOX) is a broad-spectrum antibiotic with potent anti-cancer activity. Nevertheless, despite having effective anti-neoplasm activity, its use has been clinically restricted due to its life-threatening side effects, such as cardiotoxicity. It is evident that betaine has anti-oxidant, and anti-inflammatory activity and has several beneficial effects, such as decreasing the amyloid-β generation, reducing obesity, improving steatosis and fibrosis, and activating AMP-activated protein kinase (AMPK). However, whether betaine could mitigate DOX-induced cardiomyopathy is still unexplored. Cardiomyopathy was induced in male Sprague Dawley rats using DOX (4 mg/kg dose with a cumulative dose of 20 mg/kg, i.p.). Further, betaine (200 and 400 mg/kg) was co-treated with DOX through oral gavage for 28 days. After the completion of the study, several biochemical, oxidative stress parameters, histopathology, western blotting, and qRT-PCR were performed. Betaine treatment significantly reduced CK-MB, LDH, SGOT, and triglyceride levels, which are associated with cardiotoxicity. DOX-induced increased oxidative stress was also mitigated by betaine intervention as the SOD, catalase, MDA, and nitrite levels were restored. The histopathological investigation also confirmed the cardioprotective effect of betaine against DOX-induced cardiomyopathy as the tissue injury was reversed. Further, molecular analysis revealed that betaine suppressed the DOX-induced increased expression of phospho-p53, phospho-p38 MAPK, NF-kB p65, and PINK 1 with an upregulation of AMPK and downregulation of Nrf2 expression. Interestingly, qRT-PCR experiments show that betaine treatment alleviates the DOX-induced increase in inflammatory (TNF-α, NLRP3, and IL-6) and fibrosis (TGF-β and Acta2) related gene expression, halting the cardiac injury. Interestingly, betaine also improves the mRNA expression of Nrf2, thus modulating the expression of antioxidant proteins and preventing oxidative damage. Here, we provide the first evidence that betaine treatment prevents DOX-induced cardiomyopathy by inhibiting oxidative stress, inflammation, and fibrosis by regulating AMPK/Nrf2/TGF-β expression. We believe that betaine can be utilized as a potential novel therapeutic strategy for preventing DOX-induced cardiotoxicity.

Keywords:  AMPK; betaine; cardiomyopathy; doxorubicin; fibrosis; inflammation

DOI:  https://doi.org/10.1002/tox.24291