H₂ S donor improves heart function and vascular relaxation in diabetes

Area of Science:

• Cardiovascular Research
• Endocrinology
• Pharmacology

Background:

• Diabetes mellitus significantly elevates cardiovascular disease risk and mortality.
• Hydrogen sulfide (H₂S) is recognized for its antioxidant properties and protective effects on pancreatic islet beta cells.
• H₂S has demonstrated potential in mitigating oxidant stress-induced damage and apoptosis in beta cells.

Purpose of the Study:

• To investigate the cardioprotective effects of an exogenous hydrogen sulfide donor.
• To assess the impact of sodium hydrosulphide (NaHS) on cardiac function in a rat model of diabetes.
• To evaluate the influence of NaHS on endothelium-dependent relaxation of aortic smooth muscle in diabetic conditions.

Main Methods:

• Diabetes was induced in rats using streptozotocin (STZ).
• Cardiac hemodynamic parameters were measured using a microcatheter and Pressure-Volume System.
• The effect of sodium hydrosulphide (NaHS) on aortic smooth muscle contractility and relaxation was assessed in vitro.

Main Results:

• Sodium hydrosulphide (NaHS) administration improved cardiac pumping function and restored diastolic function in STZ-induced diabetic rats.
• Pretreatment with NaHS significantly increased stroke volume (43.1%) and ejection fraction (48.64%).
• NaHS enhanced acetylcholine-induced aortic relaxation by 3.4-fold in diabetic rats, mediated by a nitric oxide synthase (NOS)-dependent mechanism, as evidenced by L-NAME inhibition.

Conclusions:

• Exogenous hydrogen sulfide, administered as NaHS, can effectively improve cardiac pumping and diastolic function in diabetic states.
• NaHS pretreatment demonstrates efficacy in preventing endothelial dysfunction in diabetes through a NOS-dependent pathway.
• These findings highlight the therapeutic potential of hydrogen sulfide donors in managing cardiovascular complications associated with diabetes.