The role of liver in leptin metabolism in experimental nephrotic syndrome

Leptin is a hormone influencing food intake, energy expenditure and body weight. It is produced by adipocytes, exerts its effects on brain, endocrine pancreas and other organs by activating trans-membrane receptors and is cleared from plasma mainly by the kidneys. Several studies have suggested that leptin's effects on metabolism are mediated by the liver. Our aim was to evaluate the role of the liver in the metabolism of leptin by comparing the serum leptin level in the portal vein with that in inferior vena cava and to study the relationship between leptin and lipoprotein levels in healthy and nephrotic rats. Experimental nephrotic syndrome was conducted in rats by intraperitoneal injection of the supernatant from the kidney suspension obtained by previous unilateral nephrectomy of the same rat and complete Freund's adjuvant. There was a highly significant rise in leptin and lipid profile levels in the nephrotic rats compared with the normal rats. A highly significant increase in leptin in the inferior vena cava was detected compared with the level in the portal veins of nephrotic rats, while insignificant difference was observed in normal rats. This work has stressed the role of liver in leptin and lipid metabolism in nephrotic rats.