Influence of long-term recombinant human erythropoietin (rHuEpo) therapy on plasma leptin and neuropeptide Y concentration in haemodialysed uraemic patients

ship.(2) Suppression of leptinaemia induced by rHuEpo may be of clinical relevance in haemodialysed Background.In patients with chronic renal failure, rHuEpo therapy ameliorates anaemia and improves patients with chronic renal failure.wellbeing, exercise tolerance, and appetite.Both leptin and neuropeptide Y play an important role in regula-Key words: anaemia; erythropoietin; haemodialysis; tion of appetite and energy balance in humans.leptin; neuropeptide Y; uraemia Methods.The present study aimed to asses the influence of 12 months rHuEpo therapy on plasma leptin and neuropeptide Y concentrations in 15 haemodialysed patients (HDP) (6F, 9M; mean age 40.8±2.9Introduction years; mean BMI 23.6±1.1 kg/m2; mean duration of HD 3.3±0.6months) (Epo group).A second group Malnutrition and loss of appetite are common signs (No-Epo group) consisted of 17 HDP (9F, 8M; mean of chronic uraemia [1].Recombinant human erythroage 44±3.2 years; mean BMI 24.3±1.0kg/m2; mean poietin (rHuEpo) is now widely used in the treatment duration of HD 2.5±0.4 months) not treated with of anaemia in haemodialysed uraemic patients (HDP).rHuEpo for 12 months.Basal plasma leptin and neuro-Apart from ameliorating anaemia, rHuEpo therapy peptide Y concentrations were estimated by RIA at improves wellbeing, exercise tolerance, and appetite the beginning and after 3, 6, 9 and 12 months of [2][3][4][5][6].Some signs and symptoms found in rHuEpo-rHuEpo therapy ( Epo group) or clinical observation treated patients, such as increased libido and potency, (No-Epo group).The control group consisted of 30 improvement of appetite, physical and mental activity, healthy subjects (15 females, 15 males, mean age= as well as some side-effects of rHuEpo therapy (exacer-38.2±1.7 years, mean BMI 24.5±0.7 kg/m2).bation of pre-existing hypertension, seizures, hyperka-Results.Baseline plasma leptin concentrations in HDP laemia) may suggest, that they are caused not only by were higher, although statistically not significant than amelioration of anaemia but also by altered function leptinaemia in healthy subjects.After 3, 6, and 12 of endocrine organs or by a direct effect of rHuEpo months of rHuEpo therapy plasma leptin concentraon the nervous system or other organs (for reviews see tions were significantly lower than at the beginning of [1,2]).As already shown in our previous studies, the study.Baseline plasma neuropeptide Y concentra-rHuEpo therapy exerts a profound effect on the hortions in HDP did not differ significantly from controls.monal status in HDP by decreasing significantly plasma After 3 and 6 months of the study period plasma levels of somatotropin [7-9], prolactin [7,8], follitroneuropeptide Y concentrations increased significantly pin, lutropin [10], glucagon, pancreatic polypeptide in patients of both the Epo and No-Epo group.This and gastrin [11], and increasing plasma concentration increase was, however, significantly higher in rHuEpoof insulin [11], oestradiol [7], testosterone [10], atrial treated than in untreated patients.natriuretic peptide [7], and thyroxine [12]. Conclusions. (1) rHuEpo treatment in haemodialysedLeptin is a 16-kDa protein, synthesized by adipopatients with chronic renal failure is followed by a cytes.It is encoded by the ob gene.Absence of leptin significant decline of leptinaemia and disappearance of in mutant ob/ob mice leads to extreme obesity, sterility, the physiological positive BMI/leptinaemia relationand diabetes mellitus type II [13].The ob gene is highly conserved among vertebrates [13].As in the