[Inulin increases the proportion of monocytic myeloid-derived suppressor cells in peripheral blood, liver, spleen and regulates the secretion of plasma inflammatory cytokines in mice with non-alcoholic fatty liver disease].

Objective To investigate the effect of inulin on monocytic myeloid-derived suppressor cells (M-MDSCs) and plasma inflammatory cytokines in mouse models with non-alcoholic fatty liver disease (NAFLD). Methods C57BL/6 mice were randomly divided into 4 groups: normal diet group, inulin-treated control group, NAFLD model group and inulin-treated NAFLD model group. The normal diet group and inulin-treated control group were given normal diet daily, while the other two groups were fed high-fat diet (60% fat) instead. Meanwhile, the mice in the two inulin-treated groups were administrated dietary inulin (5 g/kg). After 14 weeks of feeding, the mice were sacrificed and their peripheral blood, liver and spleen cells were collected. The proportion of M-MDSCs in the peripheral blood, spleen and liver cells were separately detected by flow cytometry. Concentrations of plasma inflammatory cytokines including tumor necrosis factor α (TNF-α) and interleukin 10 (IL-10) were determined by flow cytometry CBA. Statistical Pearson was used to analyze the correlation between the proportion of M-MDSCs and plasma inflammatory cytokines. Results Compared with the normal diet group, the proportion of M-MDSCs in the peripheral blood, liver and spleen of the NAFLD model group significantly increased, plasma TNF-α level also dramatically increased, but IL-10 concentration showed no significant difference from that of the normal diet group. Conversely, INU treatment, compared with the NAFLD model group without INU treatment, increased the proportion of M-MDSCs in the peripheral blood, liver and spleen notably, decreased plasma TNF-α level, and increased plasma IL-10 concentration. The proportion of M-MDSCs in the peripheral blood, liver and spleen cells of NAFLD mice were negatively correlated with plasma TNF-α level, but positively correlated with plasma IL-10 concentration. Conclusion INU may alleviate the progression of NAFLD via recruiting M-MDSCs in the peripheral blood, liver and spleen and reducing inflammation in mice.