Appetite-regulating Hormones in Chronic Kidney Disease Patients

Abstract

Objective: Inflammation and loss of appetite is the most common problem in patients with chronic kidney disease (CKD). This comparative cross-sectional study aimed to characterize the changes in circulating levels of ghrelin, obestatin, leptin, all of which have an effect on food intake, and proinflammatory cytokines interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-alpha) in patients with CKD who were undergoing different treatments. Design and Setting: Study participants included 36 patients who had undergone hemodialysis (body mass index [BMI]: 22.3 +/- 4.17 kg/m(2)); 41 who had undergone peritoneal dialysis (BMI: 23.5 +/- 3.10 kg/m(2)), 30 with early stage CKD (BMI: 24.4 +/- 3.32 kg/m(2)), and 31 healthy subjects (24.3 +/- 2.14 kg/m(2)). The patients with CKD were kept under a standard diet with restricted salt, potassium, and protein intake. Intervention: Levels of leptin, acylated ghrelin, obestatin, TNF-alpha, and IL-6 were measured by commercially available enzyme-linked immunosorbent assay kits. Total nitrite/nitrate was analyzed using colorimetric assay kit. Results: Significantly high leptin levels, accompanied by low acylated ghrelin levels, were observed in patients with CKD. Maintenance dialysis did not affect these levels. TNF-alpha and IL-6 levels were significantly higher in CKD patients than in healthy subjects, the highest being in dialysis patients. Obestatin levels were relatively low in patients who had undergone hemodialysis. Conclusion: Low acyl-ghrelin levels, accompanied with high levels of TNF-alpha and IL-6 may be involved in the loss of appetite and poor nutritional status in CKD patients. (C) 2011 by the National Kidney Foundation, Inc. All rights reserved.