REGULATION OF CHOLESTEROL METABOLISM BY HYPOTHYROIDISM IN POLYMORPHONUCLEAR LEUKOCYTES

CORIA MARIELA JANET; GIMENEZ MARIA SOFIA

TUCUMÁN

Congreso; XLV REUNIÓN ANUAL- SOCIEDAD ARGENTINA DE INVESTIGACIÓN EN BIOQUÍMICA Y BIOLOGÍA MOLECULAR; 2009

Regulation of cholesterol metabolism by hypothyroidism in polymorphonuclearleukocytes.Coria MJ, Gimenez MSIMIBIO- CONICET- Univ Nac de San LuisE-mail: marie_449@yahoo.com.arThe phagocytes are the first line of defense against infectious agents and their lipidcomposition is very important for their live and functions. The aim of this study was toassess the hypothyroidism effect on the cholesterol content in polymorphonuclearleukocytes (PMN). Methods: Female Wistar rats were separated in control (Co) andhypothyroid (HT) groups. The hypothyroidism was induced by administration of a 0.1g/L PTU in the drinking water. Food and water were administrated ad libitum. HT andCo rats were killed by decapitation after 30 days treatment for blood recollection. Inserum were assessed by enzymatic methods total (TC) and HDL cholesterol. LDLcholesterolwas calculated. PMN were isolated from blood by gradient density todetermine in them phospholipids (Fisk, 1929), total, free (FC) and esterified (EC)cholesterol (Zack, 1954) separated by thin-layer chromatography. LDL-R andHMGCoaR mRNA expression were measured in PMN. Results: LDL-col and TC wereincreased in HT group .The HDL-Col levels did not differ. The phospholipids contentshowed no differences, but the cholesterol levels (TC, FC and EC) were significantlylow in PMN of HT group. The HMG-CoAR and LDL-R mRNA levels were diminishedand not modificates, respectively, in PMN of HT. According to our results, thehypothyroidism modifies cholesterol composition of PMN leukocytes, by regulation ofits metabolism.