bims-hafaim 2023-02-05 papers

Issue of 2023–02–05
three papers selected by
Kyle McCommis, Saint Louis University

Biomed Pharmacother. 2023 Jan 31. pii: S0753-3322(23)00098-7. [Epub ahead of print]160 114310

SGLT2 inhibitor ertugliflozin decreases elevated intracellular sodium, and improves energetics and contractile function in diabetic cardiomyopathy.

Dominique Croteau, Tomas Baka, Sara Young, Huamei He, Jordan M Chambers, Fuzhong Qin, Marcello Panagia, David R Pimentel, James A Balschi, Wilson S Colucci, Ivan Luptak.

BACKGROUND: Elevated myocardial intracellular sodium ([Na+]i) was shown to decrease mitochondrial calcium ([Ca2+]MITO) via mitochondrial sodium/calcium exchanger (NCXMITO), resulting in decreased mitochondrial ATP synthesis. The sodium-glucose co-transporter 2 inhibitor (SGLT2i) ertugliflozin (ERTU) improved energetic deficit and contractile dysfunction in a mouse model of high fat, high sucrose (HFHS) diet-induced diabetic cardiomyopathy (DCMP). As SGLT2is were shown to lower [Na+]i in isolated cardiomyocytes, we hypothesized that energetic improvement in DCMP is at least partially mediated by a decrease in abnormally elevated myocardial [Na+]i.
METHODS: Forty-two eight-week-old male C57BL/6J mice were fed a control or HFHS diet for six months. In the last month, a subgroup of HFHS-fed mice was treated with ERTU. At the end of the study, left ventricular contractile function and energetics were measured simultaneously in isolated beating hearts by 31P NMR (Nuclear Magnetic Resonance) spectroscopy. A subset of untreated HFHS hearts was perfused with vehicle vs. CGP 37157, an NCXMITO inhibitor. Myocardial [Na+]i was measured by 23Na NMR spectroscopy.
RESULTS: HFHS hearts showed diastolic dysfunction, decreased contractile reserve, and impaired energetics as reflected by decreased phosphocreatine (PCr) and PCr/ATP ratio. Myocardial [Na+]i was elevated > 2-fold in HFHS (vs. control diet). ERTU reversed the impairments in HFHS hearts to levels similar to or better than control diet and decreased myocardial [Na+]i to control levels. CGP 37157 normalized the PCr/ATP ratio in HFHS hearts.
CONCLUSIONS: Elevated myocardial [Na+]i contributes to mitochondrial and contractile dysfunction in DCMP. Targeting myocardial [Na+]i and/or NCXMITO may be an effective strategy in DCMP and other forms of heart disease associated with elevated myocardial [Na+]i.

Keywords: Cardiac energetics; Contractile function; Diabetic cardiomyopathy; Ertugliflozin; Myocardial intracellular sodium; Sodium-glucose co-transporter 2 (SGLT2) inhibitor

DOI: https://doi.org/10.1016/j.biopha.2023.114310

ESC Heart Fail. 2023 Feb 01.

The cardiovascular effects of SGLT2 inhibitors, RAS inhibitors, and ARN inhibitors in heart failure.

Peng-Juan Ji, Zhuo-Ya Zhang, Qi Yan, Hui-Li Cao, Ya-Jing Zhao, Bing Yang, Jin Li.

AIMS: No studies have comprehensively compared the efficacy of sodium-glucose cotransporter-2 (SGLT2) inhibitors, renin-angiotensin system (RAS) inhibitors, and angiotensin receptor neprilysin (ARN) inhibitors based on different type of heart failure, including heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). The aim of this network meta-analysis was to evaluate the relative efficacy of SGLT2 inhibitor (SGLT2i), RAS inhibitor (RASi) and ARN inhibitor (ARNI) in different types of heart failure.
METHODS: A systemic literature search was performed from inception to 19 November 2022 for randomized control trials assessing the risk of cardiovascular (CV) death or hospitalization for heart failure (HHF) of these drugs in HF. A network meta-analysis was performed. Risk ratio (RR) with 95% confidence intervals (CI) were synthesized.
RESULTS: Seventeen studies were selected with a total of 61 489 patients. In patients with HFrEF, ARNI led to a reduced risk of a composite outcome of CV death or HHF when compared with placebo (RR = 0.83, 95% CI 0.77-0.89). Similar trends were observed when focusing on the outcome of CV death or HHF alone. In patients with HFpEF, SGLT2i showed the beneficial effects on the CV death or HHF events when compared with placebo and RASi (RR = 0.82, 95% CI 0.74-0.92; RR = 1.16, 95% CI 1.02-1.31). For CV death, all these three drugs could not show beneficial effects in HFpEF. For the incidence of HHF in HFpEF, both SGLT2i and ARNI demonstrated the beneficial effects but SGLT2i was superior to ARNI. There were no differences in the events of discontinuation under these drugs when compared with placebo or each other in either HFrEF or HFpEF patients. SGLT2i showed the least renal injury among these interventions in HFrEF and there were no differences in the incidence of renal injury of these interventions in HFpEF.
CONCLUSIONS: Among these drugs, ARNI showed the greatest ability to lower the incidence of CV death or HHF and SGLT2i exerted the least renal injury in patients with HFrEF. In patients with HFpEF, SGLT2i was associated with a reduction in the risk of CV death or HHF. There were no differences in the incidence of renal injury of these interventions in HFpEF. The intolerance of these drugs were comparable in both HFrEF and HFpEF.

Keywords: ARN inhibitors; Cardiovascular outcome; Network meta-analysis; RAS inhibitors; SGLT2 inhibitors

DOI: https://doi.org/10.1002/ehf2.14298

Transl Res. 2023 Jan 26. pii: S1931-5244(23)00004-X. [Epub ahead of print]

AAV-based gene therapy prevents and halts the progression of dilated cardiomyopathy in a mouse model of phosphoglucomutase I deficiency (PGM1-CDG).

B Balakrishnan, R Altassan, R Budhraja, W Liou, A Lupo, S Bryant, A Mankouski, S Radenkovic, G Preston, A Pandey, S Boudina, T Kozicz, E Morava, K Lai.

PGM1 deficiency is recognized as the third most common N-linked Congenital Disorders of Glycosylation (CDG) in humans. Affected individuals present with liver, musculoskeletal, endocrine, and coagulation symptoms; however, the most life-threatening complication is the early onset of dilated cardiomyopathy (DCM). Recently, we discovered that oral D-galactose supplementation improved liver disease, endocrine and coagulation abnormalities, but does not alleviate the fatal cardiomyopathy and the associated myopathy. Here we report on left ventricular ejection fraction (LVEF) in 6 individuals with PGM1-CDG. LVEF was pathologically low in most of these individuals and varied between 10-65%. To study the pathobiology of the cardiac disease observed in PGM1-CDG, we constructed a novel cardiomyocyte-specific conditional Pgm2 gene (mouse ortholog of human PGM1) knockout (Pgm2 cKO) mouse model. Echocardiography studies corroborated a DCM phenotype with significantly reduced ejection fraction and left ventricular dilation similar to those seen in individuals with PGM1-CDG. Histological studies demonstrated excess glycogen accumulation and fibrosis, while ultrastructural analysis revealed Z-disk disarray and swollen/fragmented mitochondria, which was similar to the ultrastructural pathology in the cardiac explant of an individual with PGM1-CDG. In addition, we found decreased mitochondrial function in the heart of KO mice. Transcriptomic analysis of hearts from mutant mice demonstrated a gene signature of DCM. Although proteomics revealed only mild changes in global protein expression in left ventricular tissue of mutant mice, a glycoproteomic analysis unveiled broad glycosylation changes with significant alterations in sarcolemmal proteins including different subunits of laminin-211, which was confirmed by immunoblot analyses. Finally, augmentation of PGM1 in KO mice via AAV9-PGM1 gene replacement therapy prevented and halted the progression of the DCM phenotype.

DOI: https://doi.org/10.1016/j.trsl.2023.01.004