IL-10 targets Th1/Th2 balance in vascular dementia.

OBJECTIVE

The pathogenesis of vascular dementia (VD) is not fully elucidated. Th1/Th2 balance may change in VD, leading to numerous inflammatory cytokines secretion. Interleukin-10 (IL-10) is an immune suppressor, while its function in VD and correlation with Th1/Th2 balance are still unclear.

MATERIALS AND METHODS

The healthy male rats were randomly divided into three groups, including sham group, model group, and IL-10 group. Th1 and Th2 cytokines IL-2, IL-4, IL-6, and tumor necrosis factor-α (TNF-α) expressions in the serum were tested by enzyme-linked immunosorbent assay (ELISA). IL-10 expression in brain tissue and peripheral blood was detected by Real-Time PCR and ELISA. The correlation relationship between IL-10 and T helper cells 1/2 (Th1/Th2) cytokines was analyzed. Hippocampus cell apoptosis was determined by caspase 3 activity kit. Nuclear transcription factor 2 κB (NF-κB) expression was evaluated by Western blot.

RESULTS

IL-10 levels were decreased, caspase 3 activity was enhanced, NF-κB expression was declined, IL-2 and TNF-α secretion were up-regulated, while IL-4 and IL-6 secretion were reduced in hippocampus tissue and peripheral blood from VD model rat compared to sham group (p<0.05). IL-10 significantly attenuated caspase 3 activity, up-regulated NF-κB expression, reduced IL-2 and TNF-α secretion, and enhanced IL-4 and IL-6 secretion (p<0.05). IL-10 was negatively correlated with Th1 cytokines and positively correlated with Th2 cytokines (p<0.05).

CONCLUSIONS

IL-10 expression declined in VD and participated in regulating Th1/Th2 balance. IL-10 participated in VD incidence and development through regulating cell apoptosis and NF-κB expression.