Relationship between zinc levels and plasma leptin in hemodialysis patients.
Recent evidences suggested a possible relationship between zinc deficiency and leptin levels in pathogenesis of anorexia in chronic kidney disease. The present study addressed the relationship between zinc and leptin in hemodialysis (HD) patients.


METHODS
Fifty HD patients (54.3±12.7years old, 62% men) were studied and compared to 21 healthy volunteers (50.7±15.7years old, 43% men). Biochemical data, serum zinc, plasma leptin, IL-6, TNF-α and C-Reactive Protein levels were determined. Anthropometric parameters, food intake and appetite score were also assessed.


RESULTS
The leptin levels were higher in HD patients (16.1μg/mL (0.21-118.25) vs 6.0μg/mL (0.50-23.10)) in healthy volunteers (p=0.04), whereas serum zinc levels were lower (54.5±16.3μg/dL) compared to healthy volunteers (78.4±9.4μg/dL) (p=0.0001). The plasma leptin was correlated negatively with plasma zinc (r=-0.33; p=0.007), energy (r=-0.38; p=0.002) and protein intake (r=-0.34; p=0.006) and, positively correlated with BMI (r=0.54; p=0.0001), % body fat (r=0.70; p=0.0001) and conicity index (r=0.46; p=0.001). Plasma zinc was associated with hemoglobin (r=0.30; p=0.04) and negatively associated with TNF-α (r=-0.37; p=0.002) and C-Reactive Protein (r=-0.37; p=0.004). There was no correlation among Zn, leptin and appetite score in these patients.


CONCLUSIONS
This study showed that low plasma zinc levels are negatively associated with high leptin levels in HD patients.
Federal Fluminense University (UFF), Department of Clinical Nutrition, Niterói, Brazil.
Luciana Nicolau
LN
Aranha
Julie Calixto
JC
Lobo
Milena Barcza
MB
Stockler-Pinto
Viviane de Oliveira
Vde O
Leal
João Paulo Machado
JP
Torres
Denise
D
Mafra
D000328:Adult; D000368:Aged; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015032:Zinc / Q000097:blood*
D020738:Leptin; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein; D015032:Zinc