The Crucial Roles of Phospholipids in Aging and Lifespan Regulation

Phospholipids are major membrane lipids that consist of lipid bilayers. This basic cellular structure acts as a barrier to protect the cell against various environmental insults and more importantly, enables multiple cellular processes to occur in subcellular compartments. Numerous studies have linked the complexity of membrane lipids to signal transductions, organelle functions, as well as physiological processes, and human diseases. Recently, crucial roles for membrane lipids in the aging process are beginning to emerge. In this study, we summarized current advances in our understanding of the relationship between membrane lipids and aging with an emphasis on phospholipid species. We surveyed how major phospholipid species change with age in different organisms and tissues, and some common patterns of membrane lipid change during aging were proposed. Further, the functions of different phospholipid molecules in regulating healthspan and lifespan, as well as their potential mechanisms of action, were also discussed.

Abstract MP17: Testosterone Change Relates to Lipid Change on Statins

Background: Cholesterol is a precursor for steroid hormones. We sought to assess whether as well as how lipid change in men on statins relates to testosterone change. Methods: 694 men over age 20 without DM or CVD were randomized equally to simvastatin 20mg, pravastatin 40mg or placebo for 6 months in a double blind RCT. For each arm, final (6mo) testosterone (ng/mL) was compared to baseline testosterone (paired t-tests). Testosterone-change-on-statin was compared to testosterone-change-on-placebo (unpaired t-tests). Regression examined how change in testosterone related to change in lipid elements (mg/dL), stratified by statin. Results: Baseline testosterone was comparable across arms (~4.4ng/mL). Testosterone on-treatment was significantly lower than at baseline (paired t-tests) on statins but not on placebo (Table). Testosterone drop was significantly greater in the statin than the placebo group (unpaired t-test, Table). Change in testosterone on simvastatin (but not pravastatin) related significantly to change in LDL (P<0.001). In contrast, change in testosterone on pravastatin (but not simvastatin) related significantly to change in HDL (P=0.005). Discussion: Statins produced modest but significant average declines in testosterone in men. Change in testosterone on statins related significantly to change in lipids, differently for simvastatin and pravastatin.