Exercise restores immune cell function in energy-restricted rats

Objective: To evaluate the effect of chronic moderate-intensity exercise upon the alterations of immune system cell function induced by energy restriction.Methods: Forty male Wistar rats were randomly assigned to the following groups: sedentary animals fed ad libitum (SF, N = 10) or submitted to energy restriction (SER, N = 10, receiving 50% of the mean amount of chow consumed by SF); and trained animals fed ad libitum (TF, N = 10) or submitted to energy restriction (TER, N = 10), who exercised on a treadmill (at 60-65% VO2max) 5 d(.)wk(-1) for 10 wk, after 30 d under the restriction protocol. the incorporation of [2-C-14]-thymidine by lymphocytes obtained from the spleen and mesenteric lymph nodes, plasma glucose and glutamine concentration, and cytokine production by cells cultivated in the presence of glutamine were measured in all groups, 24 h after the last exercise session. Two-way ANOVA and Tukey's posttest were employed for the statistical analysis.Results: Training induced an increase in the proliferative response and in the production of gamma-interferon and interleukin-1 (P < 0.05) in cells from the spleen and lymph nodes of SER, in which these parameters were diminished when compared with SF (P < 0.05). SER spleen and lymph node cells produced more TNF (26 and 42%, respectively) and IL-2 (49 and 42%, respectively) than SF. the Th-1-like diversion of the immune response observed in SER persisted after training. Partial recovery of the decreased SER plasma glutamine concentration and muscle glutamine synthase mRNA was observed.Conclusions: Training induced the recovery of the proliferative capacity of lymphocytes from SER, probably due to the partial restoration of plasma glutamine levels, but did not interfere with the diversion towards a Th-1-type immune response induced by food restriction.Univ São Paulo, Inst Biomed Sci 1, Dept Histol & Embryol, Lab Metab, BR-05508900 São Paulo, BrazilUniv São Paulo, Inst Biomed Sci 1, Dept Histol & Embryol, Lab Histophysiol, BR-05508900 São Paulo, BrazilUniversidade Federal de São Paulo, Sch Med, UNIFESP, Discipline Immunol, São Paulo, BrazilUniversidade Federal de São Paulo, Sch Med, UNIFESP, Discipline Immunol, São Paulo, BrazilWeb of Scienc

Incorporation of dietary trans monounsaturated fatty acids into tissues of Walker 256 tumor-bearing rats

The correlation between dietary trans fatty acids and neoplasia was examined in the present study. Walker 256 tumor-bearing and control rats were fed a trans monounsaturated fatty acid (MUFA)-rich diet for 8 weeks and the incorporation of trans fatty acids by tumor tissue was examined. Also, the effect of tumor growth on trans fatty acid composition of plasma and liver, and the content of thiobarbituric acid-reactive substances (TBARS) was determined. Walker 256 tumor cells presented both trans and cis MUFAs given in the diet. The equivalent diet proportions were 0.66 for trans and 1.14 for cis. Taking into consideration the proportion of trans MUFAs in plasma (11.47%), the tumor incorporated these fatty acids in a more efficient manner (18.27%) than the liver (9.34%). Therefore, the dietary trans fatty acids present in the diet are actively incorporated by the tumor. Tumor growth itself caused marked changes in the proportion of polyunsaturated fatty acids in the plasma and liver but provoked only slight modifications in both trans and cis MUFAs. Tumor growth also reduced the unsaturation index in both plasma and liver, from 97.79 to 86.83 and from 77.51 to 69.64, respectively. This effect was partially related to an increase in the occurrence of the lipid oxidation/peroxidation process of TBARS content which was increased in both plasma (from 0.428 to 0.505) and liver (from 9.425 to 127.792) due to tumor growth