bims-hafaim Biomed News
on Heart failure metabolism
Issue of 2023–11–05
five papers selected by
Kyle McCommis, Saint Louis University



  1. Front Cardiovasc Med. 2023 ;10 1273781
       Aims: We sought to conduct a meta-analysis to evaluate the efficacy and safety of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in patients with heart failure (HF) with preserved ejection fraction (HFpEF) and HF with mildly reduced ejection fraction (HFmrEF).
    Methods: We searched the Cochrane Library, MEDLINE (via PubMed), Embase, and ClinicalTrials.gov till March 2023 to retrieve all randomized controlled trials of SGLT2i in patients with HFpEF or HFmrEF. Risk ratios (RRs) and standardized mean differences (SMDs) with their 95% confidence intervals (95% CIs) were pooled using a random-effects model.
    Results: We included data from 14 RCTs. SGLT2i reduced the risk of the primary composite endpoint of first HF hospitalization or cardiovascular death (RR 0.81, 95% CI: 0.76, 0.87; I2 = 0%); these results were consistent across the cohorts of HFmrEF and HFpEF patients. There was no significant decrease in the risk of cardiovascular death (RR 0.96, 95% CI: 0.82, 1.13; I2 = 36%) and all-cause mortality (RR 0.97, 95% CI: 0.89, 1.05; I2 = 0%). There was a significant improvement in the quality of life in the SGLT2i group (SMD 0.13, 95% CI: 0.06, 0.20; I2 = 51%).
    Conclusion: The use of SGLT2i is associated with a lower risk of the primary composite outcome and a higher quality of life among HFpEF/HFmrEF patients. However, further research involving more extended follow-up periods is required to draw a comprehensive conclusion.
    Systematic Review Registration: PROSPERO (CRD42022364223).
    Keywords:  HFPEF; SGLT2I; dapagliflozin; empagliflozin; heart failure
    DOI:  https://doi.org/10.3389/fcvm.2023.1273781
  2. Diabetol Metab Syndr. 2023 Oct 31. 15(1): 223
       BACKGROUND: Sodium-glucose cotransporter (SGLT)2 inhibitors have displayed beneficial effects on the cardiovascular system in diabetes mellitus (DM) patients. As most clinical trials were performed in Type 2 DM, their effects in Type 1 DM have not been established.
    OBJECTIVE: To evaluate the influence of long-term treatment with SGLT2 inhibitor dapagliflozin on cardiac remodeling, myocardial function, energy metabolism, and metabolomics in rats with Type 1 DM.
    METHODS: Male Wistar rats were divided into groups: Control (C, n = 15); DM (n = 15); and DM treated with dapagliflozin (DM + DAPA, n = 15) for 30 weeks. DM was induced by streptozotocin. Dapagliflozin 5 mg/kg/day was added to chow.
    STATISTICAL ANALYSIS: ANOVA and Tukey or Kruskal-Wallis and Dunn.
    RESULTS: DM + DAPA presented lower glycemia and higher body weight than DM. Echocardiogram showed DM with left atrium dilation and left ventricular (LV) hypertrophy, dilation, and systolic and diastolic dysfunction. In LV isolated papillary muscles, DM had reduced developed tension, +dT/dt and -dT/dt in basal condition and after inotropic stimulation. All functional changes were attenuated by dapagliflozin. Hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) activity was lower in DM than C, and PFK and PK activity higher in DM + DAPA than DM. Metabolomics revealed 21 and 5 metabolites positively regulated in DM vs. C and DM + DAPA vs. DM, respectively; 6 and 3 metabolites were negatively regulated in DM vs. C and DM + DAPA vs. DM, respectively. Five metabolites that participate in cell membrane ultrastructure were higher in DM than C. Metabolites levels of N-oleoyl glutamic acid, chlorocresol and N-oleoyl-L-serine were lower and phosphatidylethanolamine and ceramide higher in DM + DAPA than DM.
    CONCLUSION: Long-term treatment with dapagliflozin attenuates cardiac remodeling, myocardial dysfunction, and contractile reserve impairment in Type 1 diabetic rats. The functional improvement is combined with restored pyruvate kinase and phosphofructokinase activity and attenuated metabolomics changes.
    Keywords:  Echocardiogram; Myocardial metabolomics; Papillary muscle; SGLT2 inhibitors; Streptozotocin; Ventricular function
    DOI:  https://doi.org/10.1186/s13098-023-01196-6
  3. JACC Heart Fail. 2023 Oct 12. pii: S2213-1779(23)00596-6. [Epub ahead of print]
       BACKGROUND: Certain antineoplastic therapies are associated with an increased risk of cardiomyopathy and heart failure (HF). Sodium-glucose cotransporter-2 (SGLT2) inhibitors improve outcomes in patients with HF.
    OBJECTIVES: This study aims to examine the efficacy of SGLT2 inhibitors in patients with cancer therapy-related cardiac dysfunction (CTRCD) or HF.
    METHODS: The authors conducted a retrospective cohort analysis of deidentified, aggregate patient data from the TriNetX research network. Patients aged ≥18 years with a history of type 2 diabetes mellitus, cancer, and exposure to potentially cardiotoxic antineoplastic therapies, with a subsequent diagnosis of cardiomyopathy or HF between January 1, 2013, and April 30, 2020, were identified. Patients with ischemic heart disease were excluded. Patients receiving guideline-directed medical therapy were divided into 2 groups based on SGLT2 inhibitor use. After propensity score matching, odds ratios (ORs) and Cox proportional HRs were used to compare outcomes over a 2-year follow-up period.
    RESULTS: The study cohort included 1,280 patients with CTRCD/HF (n = 640 per group; mean age: 67.6 years; 41.6% female; 68% White). Patients on SGLT2 inhibitors in addition to conventional guideline-directed medical therapy had a lower risk of acute HF exacerbation (OR: 0.483 [95% CI: 0.36-0.65]; P < 0.001) and all-cause mortality (OR: 0.296 [95% CI: 0.22-0.40]; P = 0.001). All-cause hospitalizations or emergency department visits (OR: 0.479; 95% CI: 0.383-0.599; P < 0.001), atrial fibrillation/flutter (OR: 0.397 [95% CI: 0.213-0.737]; P = 0.003), acute kidney injury (OR: 0.486 [95% CI: 0.382-0.619]; P < 0.001), and need for renal replacement therapy (OR: 0.398 [95% CI: 0.189-0.839]; P = 0.012) were also less frequent in patients on SGLT2 inhibitors.
    CONCLUSIONS: SGLT2 inhibitor use is associated with improved outcomes in patients with CTRCD/HF.
    Keywords:  SGLT2 inhibitors; antineoplastic therapy; cardiomyopathy; outcomes
    DOI:  https://doi.org/10.1016/j.jchf.2023.08.026
  4. Elife. 2023 Nov 01. pii: e84235. [Epub ahead of print]12
      Cardiac muscle has the highest mitochondrial density of any human tissue, but mitochondrial dysfunction is not a recognized cause of isolated cardiomyopathy. Here, we determined that the rare mitofusin (MFN) 2 R400Q mutation is 15-20× over-represented in clinical cardiomyopathy, whereas this specific mutation is not reported as a cause of MFN2 mutant-induced peripheral neuropathy, Charcot-Marie-Tooth disease type 2A (CMT2A). Accordingly, we interrogated the enzymatic, biophysical, and functional characteristics of MFN2 Q400 versus wild-type and CMT2A-causing MFN2 mutants. All MFN2 mutants had impaired mitochondrial fusion, the canonical MFN2 function. Compared to MFN2 T105M that lacked catalytic GTPase activity and exhibited normal activation-induced changes in conformation, MFN2 R400Q and M376A had normal GTPase activity with impaired conformational shifting. MFN2 R400Q did not suppress mitochondrial motility, provoke mitochondrial depolarization, or dominantly suppress mitochondrial respiration like MFN2 T105M. By contrast to MFN2 T105M and M376A, MFN2 R400Q was uniquely defective in recruiting Parkin to mitochondria. CRISPR editing of the R400Q mutation into the mouse Mfn2 gene induced perinatal cardiomyopathy with no other organ involvement; knock-in of Mfn2 T105M or M376V did not affect the heart. RNA sequencing and metabolomics of cardiomyopathic Mfn2 Q/Q400 hearts revealed signature abnormalities recapitulating experimental mitophagic cardiomyopathy. Indeed, cultured cardiomyoblasts and in vivo cardiomyocytes expressing MFN2 Q400 had mitophagy defects with increased sensitivity to doxorubicin. MFN2 R400Q is the first known natural mitophagy-defective MFN2 mutant. Its unique profile of dysfunction evokes mitophagic cardiomyopathy, suggesting a mechanism for enrichment in clinical cardiomyopathy.
    Keywords:  cardiomyopathy; developmental biology; heart; mitochondria; mitofusins; mouse
    DOI:  https://doi.org/10.7554/eLife.84235
  5. Front Endocrinol (Lausanne). 2023 ;14 1181044
       Introduction: Sex differences in the adaptation to pressure overload have been described in humans, as well as animal models, and have been related to sex-specific expression of mitochondrial genes. We therefore tested whether sex differences in cardiac mitochondrial respiration exist in humans with aortic stenosis (AS). We also examined whether these potential differences may be at least partially due to sex hormones by testing if mitochondrial respiration is affected by estrogen (17ß-estradiol (E2)).
    Methods: Consecutive patients undergoing transapical aortic valve implantation (TAVI) (women, n = 7; men, n = 10) were included. Cardiac biopsies were obtained during TAVI and used directly for mitochondrial function measurements. Male and female C57BL/6J mice (n = 8/group) underwent sham surgery or gonadectomy (GDX) at the age of 2 months. After 14 days, mice were treated once with intraperitoneally injected vehicle (placebo), 17ß-estradiol (E2), estrogen receptor alpha (ERα) agonist [propyl pyrazole triol (PPT)], or ER beta (ERβ) agonist (BAY-1214257). Thereafter, mitochondrial measurements were performed directly in cardiac skinned fibers from isolated left ventricles and musculus solei.
    Results: Mitochondrial State-3 respiration was higher in female than that in male human heart biopsies (15.0 ± 2.30 vs. 10.3 ± 2.05 nmol/mL/min/mg, p< 0.05). In the mouse model, mitochondrial State-3 respiration decreased significantly after GDX in female (27.6 ± 1.55 vs. 21.4 ± 1.71 nmol/mL/min/mg; p< 0.05) and male hearts (30.7 ± 1,48 vs. 23.7 ± 2,23 nmol/mL/min/mg; p< 0.05). In ovariectomized female mice, E2 and ERβ-agonist treatment restored the State-3 respiration to intact placebo level, whereas ERα-agonist treatment did not modulate State-3 respiration. The treatment with E2, ERα-, or ERβ-agonist did not modulate the State-3 respiration in GDX male mice.
    Conclusion: We identified sex differences in mitochondrial respiration in the diseased human heart. This is in alignment with known sex differences in the gene expression and proteome level at the functional level. E2 and ERβ affect cardiac mitochondrial function in the mouse model, suggesting that they may also contribute to the sex differences in the human heart. Their roles should be further investigated.
    Keywords:  aortic stenosis; cardiac mitochondrial function; estrogen; estrogen receptor modulation; sex differences
    DOI:  https://doi.org/10.3389/fendo.2023.1181044