RESUMO
Leptin is an adipocytokine peptide involved in the homeostasis of body composition. Alterations in leptin regulation have been observed in liver cirrhosis. We aimed to assess serum and ascitic fluid leptin levels in a group of patients with decompensated liver cirrhosis and to evaluate these levels in relation to tumor necrosis factor-alpha levels. We assessed both serum and ascitic fluid leptin levels by a radioimmunoassay method, in 40 patients with posthepatic cirrhosis. We calculated body mass index [BMI] as Kg/m2 in all patients and assessed other laboratory biochemical parameters of liver functions. We excluded patients with Spontaneous bacterial peritonitis and all forms of non cirrhotic ascites. Both serum and ascitic leptin levels were correlated with BMI. Ascitic fluid leptin levels [13.1 +/- 10.9 ng/ml] were twice as high as serum levels [7.0 +/- 6.4 ng/ml] and the ascitic fluid/serum ratio of leptin was >1 in all patients. We suggested that this parameter can be used as one of the characteristics of cirrhotic ascites. Serum and ascitic fluid leptin levels were positively highly correlated [r = 0.76 p<0.001] while no correlation was found between TNF-alpha levels in serum and ascites [r=0.29 p>0.05]. We concluded from this study that ascitic fluid leptin levels of cirrhotic patients with sterile ascites are on average two times higher than circulating levels of this hormone, a useful marker of characterizing cirrhotic ascites. These findings suggest that intra-abdominal production of leptin in cirrhotic ascites by peritoneal adipocytes may explain this local rise of leptin levels and this is largely regulated and interrelated to TNF-alpha. Both proinflammatory adipocytokines are related to the metabolic picture in cirrhotic patients particularly anorexia, cachexia and increased energy expenditure. This may represent a therapeutic target in the future by means of introducing anticytokine therapy or chemoprophylactic measures that may ameliorate the release of these cytokines from stimulated monocytes, T-cells or from adipocytes