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Salvas, J. P.

Publications and source records attributed to Salvas, J. P..

2 recordsLinked to original sources

Empagliflozin preserves cardiac function and modulates metabolism in a mouse model of Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is a fatal genetic disorder characterized by skeletal muscle degeneration and cardiomyopathy without a cure. This study examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin (EMPA) on cardiac function in the dystrophin-deficient mdx mouse model of DMD. Male mice were fed control chow or EMPA-containing chow ([~]25 mg/kg/day), and cardiac function was evaluated longitudinally by four-dimensional ultrasound imaging. EMPA did not alter left ventricular mass or chamber volume but preserved ejection fraction (EF) for 12 weeks, maintained significantly higher EF through 24 weeks, and attenuated global impairment of systolic and diastolic myocardial deformation. These functional improvements were accompanied by reduced cardiomyocyte hypertrophy and decreased expression of cardiac stress genes. EMPA reduced mitochondrial DNA damage, increased mitochondrial DNA copy number, and induced transcriptional signatures consistent with enhanced fatty acid and ketone metabolism, contributing to increased myocardial ATP content. Systemically, EMPA improved body mass trajectory, preserved relative lean mass, enhanced skeletal muscle torque, and did not adversely affect renal function. Together, these findings demonstrate that EMPA improves cardiac performance and mitochondrial integrity while enhancing myocardial energy availability in mdx mice, supporting SGLT2 inhibitors as a promising therapeutic strategy for individuals with DMD.

physiology↗

Left Atrial Strain as a Predictor of Cardiac Dysfunction in a Murine Model of Pressure Overload

AimLeft atrial (LA) strain is emerging as a valuable metric for evaluating cardiac function, particularly under pathological conditions such as pressure overload. This preclinical study investigates the predictive utility of LA strain on cardiac function in a murine model subjected to pressure overload, mimicking pathologies such as hypertension and aortic stenosis. MethodsHigh resolution ultrasound was performed in a cohort of mice (n=16) to evaluate left atrial and left ventricular function at baseline and 2- and 4-weeks after transverse aortic constriction (TAC). Acute adaptations in cardiac function were assessed in a subgroup of mice (n=10) with 3-days post TAC imaging. ResultsWe report an increase in LA max volume from 11.0 {+/-} 4.3{micro}L at baseline to 26.7 {+/-} 16.7{micro}L at 4 weeks (p=0.002) and a decrease in LA strain from 19.6 {+/-} 4.8% at baseline to 10.1 {+/-} 6.3% at 4 weeks (p=0.006). In the acute phase, LA strain dysfunction was present at 3-days (p<0.001) prior to alterations in LA volume (p=0.856) or left ventricular (LV) ejection fraction (p=0.120). LA strain correlated with key indicators of cardiac performance including left ventricular (LV) ejection fraction (r=0.563, p<0.001), longitudinal strain (r=-0.643, p<0.001) and strain rate (r=0.387, p=0.007). Furthermore, markers of atrial structure and function including LA max volume (AUC=0.858, p<0.001), ejection fraction (AUC=0.901 p<0.001), and strain (AUC=0.878, p<0.001) all predicted LV dysfunction. ConclusionLA strain and function assessments provide a reliable, non-invasive method for early detection and prediction of cardiac dysfunction in a model of pressure overload.

physiology↗