Effect of D-limonene on expression of NF-κB/IκB and TNF-αin rats with alcohol-induced brain injury

LYU Hai-tao; LIANG Hui; WANG Wen-cheng; WANG Xiao-mei; LIU Ying

doi:10.3969/j.issn.1002-266X.2015.27.007

Abstract：Objective To observe the effect of D-limonene on the NF-κB/IκB expression and serum TNF-αconcen-tration in rats with alcohol-induced brain injury.Methods Sixty Wistar rats were divided into six groups, with ten rats in each group.The rat models of alcoholic brain damage were made in the drug groups 1, 2, 3 and model group, which were administered with 50%ethanol by gavage, daily, 8 mL/(kg· d) in the first two weeks, 12 mL/(kg· d) in the following four weeks.At the same time, the rats in the drug groups 1, 2 and 3 were respectively treated with 100, 200 and 400 mg/(kg· d) D-lemonene by gavage.We did not make the animal model in the simple drug group and blank control group, but rats in the blank control group were treated with distilled water, and rats in the simple drug group were treated with 400 mg/( kg· d) D-limonene based on distilled water by gavage.After six weeks, the animals were all executed and the histol-ogy of brain was examined by HE staining and light microscope.The expression of NF-κB and I-κB in the brain tissues were tested by immunohistochemical method.In addition, the activity of TNF-αin brain was examined by a double antibody sandwich ELISA.Results The number of neurons in the model group was decreased, which showed irregular distribu-tion, nuclear obviously contracted and deformed, and the morphology of brain tissues in the drug groups 1, 2 and 3 gradu-ally reduced.Significant differences in the NF-κB positive cells and I-κB positive cells were found between the model group and the blank control group (all P<0.05).The NF-κB positive cells were decreased and the NF-κB positive cells were in-creased in the drug groups 1, 2 and 3 as compared with that of the model group (all P<0.05);and significant differences were found between group 3 and the drug groups 1 and 2 (all P<0.05).TNF-αexpression in rat brain homogenate of the model group was higher than that of the blank control group (P<0.05);the expression of TNF-αin rat brain homogenates of drug groups 1, 2 and 3 was decreased as compared with that of the model group (all P<0.05); and the drug group 3 was lower than the drug groups 1 and 2 (all P<0.05).Conclusion D-Limonene may alleviate the alcoholic brain inju-ries by down-regulating the expression of NF-κB and TNF-αand up-regulating the expression of I-κB.