Protective effects of curcumin on sepsis-induced lymphocyte apoptosis in mice

Abstract

Objective To investigate the effects of curcumin on lymphocytes apoptosis in septic mice and elucidate the underlying mechanisms.Methods Sixty male BALB/c mice of clean grade were randomly divided into three groups:sham operation group (n =20),sepsis model group (n =20) and curcumin treatment group (n =20).The experiment was repeated three times.Mice in both sepsis group and curcumin group were made to be sepsis models by cecal ligation and puncture (CLP).Curcumin was intragastrically administrated in dose of 200 mg/ (kg · d) for two weeks before operation in curcumin group.And mice in sham group were only treated with open abdominal procedure without ligation and puncture.The mortality of mice in each group was calculated 24 h after operation and all the survived mice were sacrificed for theirs splenic lymphocytes collection by gradient centrifugation.Apoptosis of lymphocytes and mitochondrial membrane potential were detected by flow cytometry and Cyt C,Bax were detected by Western blot.SPSS version 16.0 software was used for statistical analysis.The measurement data were analyzed by using One-way analysis of variance (ANOVA),and counting data were analyzed by using chisquare test.Results The mortality rate of mice in sepsis group was higher than that in sham group (33.3 ％ vs.0.0％,P =0.000).And curcumin significantly reduced the mortality rate compared with sepsis group (16.6％ vs.33.3％,P =0.035).Compared with sham group,sepsis group presented a significant increase in lymphocytes apoptosis (41.2 ± 3.8) ％ vs.(8.0 ± 1.7) ％,P =0.000,which was markedly attenuated by curcumin administration (27.3 ± 1.3) ％ vs.(41.2 ± 3.8) ％,P =0.000.Meanwhile,mitochondrial membrane potentials in sepsis group were lower than those in sham group (40.4 ± 1.9)％ vs.(79.9 ± 2.1) ％,P =0.000,which was significantly increased by curcumin protection (57.7 ± 1.6) ％ vs.(40.4 ± 1.9) ％,P =0.000.The expressions of Cyt C,Bax in sepsis group significantly increased compared with sham group (P =0.000).Pretreatment with curcumin lessened the changes in levels of Cyt C (P =0.037) and Bax (P =0.000).Conclusion The curcumin reduces splenic lymphocytes apoptosis by inhibition of mitochondrion-dependent pathway in mice with sepsis. Key words: Sepsis; Mice; Lymphocyte; Apoptosis; Curcumin; Mitochondrion-dependent pathway