Heart-specific Rpd3 downregulation enhances cardiac function and longevity

Area of Science:

• Aging research
• Molecular biology
• Genetics

Background:

• Rpd3, a homologue of mammalian Histone Deacetylase 1 (HDAC1), is known to extend lifespan when downregulated in Drosophila melanogaster.
• Long-lived fruit flies exhibit reduced cardiac decline, suggesting a link between cardiac health and longevity.

Purpose of the Study:

• To investigate if heart-specific Rpd3 downregulation enhances stress resistance and lifespan in fruit flies.
• To determine the systemic effects of heart-specific Rpd3 downregulation on anti-aging gene expression and cardiac function.

Main Methods:

• Utilized Drosophila melanogaster models with targeted downregulation of Rpd3 in cardiac tissue.
• Assessed stress resistance against oxidation, starvation, and heat.
• Measured expression levels of anti-aging genes (sod2, foxo, Thor).
• Evaluated cardiac function, including heart rate, heart failure, and recovery.

Main Results:

• Heart-specific Rpd3 downregulation significantly enhanced resistance to oxidative stress, starvation, and heat.
• Systemic expression of anti-aging genes (sod2, foxo, Thor) increased following heart-specific Rpd3 downregulation.
• Improved cardiac function was observed, characterized by increased heart rate, decreased heart failure, and accelerated recovery.
• Conversely, Rpd3 upregulation in cardiac tissue reduced heat stress resistance and impaired cardiac function.

Conclusions:

• Rpd3 deacetylase in the heart plays a significant role in modulating the fly's systemic response to environmental stressors.
• Targeting Rpd3 in the heart offers a potential strategy for enhancing cardiac function and extending lifespan.
• Phosphorylated Rpd3 levels are identified as a key modulator of cardiac function and longevity.