ABSTRACT
The effect of megadoses of nicotinic acid [niacin, vitamin B3] on lipids turnover and atherosclerosis was evaluated in male adult mice fed diets containing different levels of nicotinic acid Six groups each of eight mice, mean weight varied between 17.1 to 19.6 g were fed on either basal control diet containing 30 mg nicotinic acid/kg diet or experimental diets containing 300,1500,3000,4500 and 6000 mg nicotinic acid/kg diet. Production performance and serum biochemical parameters were evaluated. Relative weights of liver and brain were significantly different while relative weights of heart showed no significant variations between different groups. The values of serum total lipids, cholesterol, LDL-cholesterol and glucose were significantly decreased in mice fed on diets containing 300mg [G2], 1500mg [G3] and 3000mg [G4] of nicotinic acid/kg diet and increased in groups containing 4500mg [G5] and 6000mg [G6] when compared with control group. Whereas, serum triacylglycerols and VLDL-cholesterol concentrations were significantly decreased in all groups except G6 as compared with control group. Significant increase in serum HDL-cholesterol values and HDL-c/LDL-c ratio were observed in G2,G3 and G4 and decreased in G5 and G6.Serum levels of creatine kinase activity [CK] enzyme were not affected by different treatments. While levels of lactate dehydrogenase [LDH] enzyme were significantly increased in all groups as compared with the control group, It was concluded that high doses of niacin rang between 300 to 3000 mg/kg diet had hypolipidemic action and reduced the hazards of atherosclerosis in mice