Calorie restricted diet induces alternative pathways of lipid metabolism for support of proliferative processes in regenerating liver.

Abstract

This study deals with quality and quantity lipid composition of blood serum and liver, DNA synthesis activity (incorporation of H3-thymidine) in liver in 24 h after partial hepatectomy (PH) in 22-month-old Wistar rats, maintained for 21 months on calorie restricted diet (CRD) and on standard diet ad libitum (SD). The contain of lipids in blood serum and activity of RA-label incorporation (14C-Na-acetate) in serum lipids in 24 h after PH were the same in CRD-fed and SD-fed animals. Quantitative and qualitative composition of lipids in microsomes of regenerating liver also was the same for both groups of rats. In regenerating liver of CRD-fed animals lipid contain in cytosol was 1,8-fold more, but pool of lipid droplets (LD) was 1.5-fold less than in regenerating liver of SD-fed animals. Activity of RA-label incorporation in lipids of microsomes, cytosol and LD pool of regenerating liver of CRD-fed animals was significantly higher, than in SD-fed ones. Activity of RA-label incorporation in lipid fractions and its distribution among cytosol lipids and LD pool lipids differed significantly between SD- and CRD-fed animals. Activity of DNA synthesis in regenerating liver of 22-month-old animals on CRD and SD was the same. It is supposed that calorie restriction induces alternative pathways of lipid metabolism to support proliferation processes in liver after PH.