Estrogens increase cystathionine-γ-lyase expression and decrease inflammation and oxidative stress in the myocardium...

Area of Science:

• Cardiovascular Physiology
• Endocrinology
• Biochemistry

Background:

• Hydrogen sulfide (H2S) is endogenously produced in the myocardium, primarily via cystathionine-γ-lyase (CSE), and exhibits cardioprotective properties.
• Estrogens, particularly 17β-estradiol (E2), are known to influence cardiovascular health, but their specific impact on myocardial H2S generation and related pathways requires elucidation.

Purpose of the Study:

• To investigate the effects of E2 on CSE expression and H2S generation within the myocardium.
• To determine the association between serum E2 levels and myocardial CSE activity and H2S production.
• To examine the relationship between E2/H2S levels and markers of oxidative stress and inflammation.

Main Methods:

• Ovariectomized rats were treated with E2 or vehicle for 12 weeks.
• Measurements included myocardial CSE expression, H2S generation, antioxidant capacity (GSH/GSSG ratio, T-AOC, SOD, CAT), and inflammatory markers (IL-6, TNF-α).

Main Results:

• E2 administration significantly increased myocardial CSE expression and H2S generation.
• Serum E2 levels positively correlated with H2S production and markers of antioxidant capacity (GSH/GSSG, T-AOC, SOD, CAT).
• E2 treatment and higher serum E2 levels were associated with reduced levels of proinflammatory cytokines (IL-6, TNF-α).

Conclusions:

• 17β-estradiol upregulates CSE expression and enhances endogenous H2S generation in the heart.
• These effects are linked to a reduction in oxidative stress and inflammation.
• Estrogens may confer cardioprotection by increasing myocardial H2S production via CSE pathway activation.