Testosterone replacement in hypogonadal men alters the HDL proteome but not HDL cholesterol efflux capacity

Area of Science:

• Endocrinology
• Cardiovascular Science
• Lipid Metabolism

Background:

• The role of androgens in men's cardiovascular disease (CVD) risk is not fully understood.
• Investigating the link between androgens and high-density lipoprotein (HDL) is crucial for assessing CVD risk.

Purpose of the Study:

• To examine how testosterone replacement therapy affects HDL protein composition and cholesterol efflux in hypogonadal men.
• To determine if dutasteride influences these effects.

Main Methods:

• Twenty-three older hypogonadal men received testosterone therapy (with or without dutasteride).
• Measurements included fasting lipids, HDL protein composition, and serum HDL-mediated cholesterol efflux at baseline and after three months.
• Statistical analyses were performed to compare treatment effects.

Main Results:

• Testosterone replacement did not alter HDL cholesterol levels.
• Significant increases were observed in HDL-associated paraoxonase 1 (PON1) and fibrinogen alpha chain (FGA).
• A significant decrease in apolipoprotein A-IV (apoA-IV) was noted; cholesterol efflux capacity remained unchanged. No differences were found between testosterone-only and testosterone plus dutasteride groups.

Conclusions:

• Testosterone replacement in older hypogonadal men modifies HDL protein composition but does not significantly alter cholesterol efflux.
• These effects are independent of testosterone conversion to dihydrotestosterone.
• Further research is needed to clarify the impact of altered HDL protein content on men's CVD risk.