CONSEQUENCES OF AGING ON THE CIRCADIAN VARIATION OF LIPID PROFILES

KLUSCH, E; CORIA LUCERO, C; FERNANDEZ G; NAVIGATORE FONZO LS; ANZULOVICH AC; PONCE IT

MENDOZA

Congreso; XXXVI REUNION CIENTIFICA DE LA SOCIEDAD DE BIOLOGIA DE CUYO; 2018

Aging is associated with declines in multiple physiological systems, resulting in increased risk for the development of disease such as the metabolic syndrome (MetS), among others. MetS is defined as a cluster of metabolic abnormalities including central obesity, hypertension, highserum triglycerides, decreased high density lipoprotein (HDL), cholesterol and glucose intolerance.Epidemiologic studies have demonstrated a marked increase in prevalence of MetS in younger people (20? 65 years).Also, aging is associated to alter circadian rhythms. The objective of this work was to investigate the consequences of aging on the circadian variation of lipid profiles. Holtzman rats3-month-oldand 22-month-old(aged) groups were maintained under constant darkness conditions, during 10 daysbefore the experiment. On the experiment day, they were sacrificed every 4hs and blood samples were collected.Serum triglycerides, total cholesterol and HDLc levels were determined by colorimetric assays. Triglycerides and total cholesterol levels display an endogenously-controlled temporal variation. We also found HDLc levels do not vary throughout a 24h periodunder constant darkness conditions, in serum of young rats. Noteworthy, aging abolished circadian rhythms of triglycerides and total cholesterol levels. This could be a biochemical basis of altered temporal patterns of lipid profiles in aged persons.