Hypothesis: link between endogenous retroviruses and cardiovascular disease

Area of Science:

• Cardiovascular Science
• Genetics
• Molecular Biology

Background:

• Endogenous retroviruses (ERVs) are genetic elements integrated into host genomes.
• Their role in cardiovascular disease, particularly hypertension, remains largely unexplored.
• Spontaneously hypertensive rats (SHR) serve as a model for human genetic hypertension.

Purpose of the Study:

• To investigate the expression of endogenous retroviruses in SHR compared to normotensive Wistar-Kyoto (WKY) rats.
• To determine if increased retroviral expression is a consequence of pressure overload or a genetic trait associated with hypertension.
• To explore the potential link between ERVs and the development of genetic hypertension.

Main Methods:

• Quantitative analysis of proviral transcripts in cardiac myocytes from SHR and WKY rats.
• Comparison of retroviral expression in SHR with WKY rats subjected to aortic banding-induced hypertrophy.
• Genetic crossbreeding of SHR and WKY rats to analyze co-segregation of hypertension and retroviral gene expression.

Main Results:

• A two-order-magnitude increase in endogenous retrovirus expression was observed in SHR myocytes compared to WKY rats.
• Hypertrophied WKY hearts from aortic banding did not show increased retroviral expression, ruling out pressure overload as the cause.
• Hybrid offspring exhibited intermediate blood pressure, hypertrophy, and retroviral gene expression, indicating co-segregation.

Conclusions:

• The increased expression of a specific endogenous retrovirus is strongly associated with genetic hypertension in SHR.
• This association is independent of pressure-induced cardiac hypertrophy.
• Findings suggest a potential role for endogenous retroviruses in the pathogenesis of genetic hypertension and cardiovascular disease.