Serum ghrelin concentrations in patients with chronic renal failure undergoing dialysis.
BACKGROUND
Ghrelin is a recently discovered protein hormone mainly synthesized in the gastric endocrine cells. This hormone not only is a potent growth hormone secretagogue but also is involved in the regulation of food ingestion and energy metabolism. Derangements in ghrelin secretion in patients with chronic renal failure (CRF) have not been fully evaluated.


OBJECTIVE
Our aim has been to quantify serum concentrations of total ghrelin in a group of patients with CRF on chronic therapy with both haemodialysis (HD) and peritoneal dialysis (PD) in comparison with a group of patients on conservative management (predialysis).


METHODS
We studied 68 CRF patients treated by HD (n = 30, 16 men, age 61.2 +/- 1.8 years) and PD groups (n = 38, 21 men, age 54.4 +/- 1.7 years). A group of 19 uraemic patients on conservative management served as the control. Serum concentrations of ghrelin, leptin, insulin, IGF I and GH were measured in all subjects.


RESULTS
Patients undergoing HD showed similar concentrations of ghrelin in comparison with the control group (9491 +/- 787 vs 9280 +/- 918 pg/ml, NS). However, PD patients exhibited baseline ghrelin concentrations significantly lower than those found in patients on conservative management (3230 +/- 216 pg/ml, P < 0.0001). Men and women showed similar serum ghrelin levels in both HD (9845.9 +/- 1071 vs 9085 +/- 1194 pg/ml) and PD patients (3214 +/- 297 vs 3250 +/- 324 pg/ml). Hypertension and diabetes mellitus did not influence ghrelin levels. Serum GH levels were positively correlated with serum ghrelin concentrations in both HD (r = 0.46, P < 0.05) and PD (r = 0.53, P < 0.001) patients; however, no relationships between ghrelin, leptin, insulin and IGF I were found.


CONCLUSIONS
These results suggest that PD is accompanied by a striking decrement in baseline ghrelin concentrations in comparison with values found both in HD and control patients. Further studies are necessary to determine mechanisms involved in ghrelin regulation in uraemic patients.
Iglesias
Pedro
P
Department of Endocrinology, Hospital General de Segovia, Spain. piglesias@hgse.sacyl.es
Díez
Juan J
JJ
Fernández-Reyes
María J
MJ
Codoceo
Rosa
R
Alvarez-Fidalgo
Pilar
P
Bajo
María A
MA
Aguilera
Abelardo
A
Selgas
Rafael
R
D000328:Adult; D016022:Case-Control Studies; D048909:Diabetes Complications / Q000097:blood; D004921:Erythropoietin / Q000627:therapeutic use; D005260:Female; D054439:Ghrelin; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications; D007328:Insulin / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000150:complications / Q000628:therapy*; D020738:Leptin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D036361:Peptide Hormones / Q000097:blood*; D010530:Peritoneal Dialysis; D011994:Recombinant Proteins; D012044:Regression Analysis; D006435:Renal Dialysis
D054439:Ghrelin; D007328:Insulin; D020738:Leptin; D008055:Lipids; D036361:Peptide Hormones; D011994:Recombinant Proteins; D004921:Erythropoietin; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone