Stimulation of the Nicotine Antiinflammatory Pathway Improves Food Intake and Body Composition in Tumor-Bearing Rats

Abstract

Inflammation contributes to the pathogenesis of cancer anorexia-cachexia syndrome. Nicotine administration reduces cytokine levels and mortality during sepsis. Therefore, nicotine administration may result in improved anorexia-cachexia. Sixteen male Fischer rats inoculated with MCA sarcoma were assigned to random injections of nicotine (NIC; 200 mg/kg BW/d) or saline (C). Food intake (FI), body weight, body composition, interleukin (IL)-1, IL-6 levels were evaluated. Data were analyzed via Student's t-test for paired and unpaired data and ANOVA. FI started declining 12 days after tumor inoculation both in C and NIC rats, but the decline was significantly attenuated by nicotine administration. At the end of the study, lean body mass wasting was more severe in C rats than in NIC rats (P 0.05), whereas a trend toward attenuation of fat mass depletion was observed. IL-1 circulating levels were significantly lower in NIC rats than in C rats (114 +/- 21 pg/mL vs. 190 +/- 35 pg/mL, respectively; P 0.01), whereas the reduction of IL-6 levels in NIC rats was only marginally not significant when compared to C rats (555 +/- 174 pg/mL vs. 721 +/- 160 pg/mL, respectively; P = 0.06). Our data suggest that the nicotinic antiinflammatory pathway may represent an interesting and possibly effective therapy for anorexia-cachexia syndrome