Interleukin 1 alpha increases serum leptin concentrations in humans.
Leptin, the protein product of the ob gene, regulates appetite and body weight in animals. Endotoxin and cytokines, induced by endotoxin, interleukin (IL) 1 and tumor necrosis factor, increase expression of leptin in mice and hamsters. We measured serum leptin concentrations in patients with cancer before and after administration of recombinant human IL-1 alpha. Fourteen patients received IL-1 alpha at one of three dose levels (0.03, 0.1, or 0.3 microgram/kg.day) for 5 days. Serum leptin concentrations increased in all but two patients within 24 h after the first dose. The increase in leptin was correlated directly with IL-1 alpha dose (P = 0.0030). Despite continued administration of IL-1 alpha, serum leptin concentrations returned to pretreatment levels by day 5 of therapy. An increase in serum leptin concentrations may be one mechanism by which anorexia is induced by IL-1 alpha. However, tachyphylaxis of the leptin response suggests that other mechanisms also are involved.
Janik
J E
JE
Medicine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-1906, USA.
Curti
B D
BD
Considine
R V
RV
Rager
H C
HC
Powers
G C
GC
Alvord
W G
WG
Smith
J W
JW
Gause
B L
BL
Kopp
W C
WC
D000328:Adult; D000368:Aged; D001066:Appetite / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D020738:Leptin; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D011506:Proteins / Q000378:metabolism*; D011994:Recombinant Proteins; D012189:Retrospective Studies; D013997:Time Factors
D007375:Interleukin-1; D020738:Leptin; D011506:Proteins; D011994:Recombinant Proteins