Abstract:The regulatory effects of crude polysaccharides extracted from Prunella vulgaris L. (PVCP) on cadmium-induced inflammatory responses in human renal proximal tubule epithelial cells RPTEC/TERT1 were investigated. Cell counting kit-8 (CCK-8) assay was used to detect the survival rate of RPTEC/TERT1 cells after cadmium or PVCP treatment for 24h. Control group (blank culture medium), model group (8 μmol/L cadmiumchloride) and high-，medium- and low-dose groups of PVCP (8 μmol/L cadmiumchloride +200, 100, 50 μg/mL PVCP)were set in this study. The catalase (CAT) and superoxide dismutase (SOD) activities of RPTEC/TERT1 cells, interleukin (IL)-6, IL-1β, IL-18 and tumor necrosis factor (TNF)-α levels in the supernatant and the protein expression levels of iκB and p65 were evaluated. The results showed that the content of polysaccharides in Prunella vulgaris L. sample was 2.14%. The viability of RPTEC/TERT1 cells was significantly inhibited by cadmium chloride in a dose-dependent manner. In addition, the activities of SOD and CAT of RPTEC/TERT1 cells in the cadmium treated group were significantly decreased (p＜0.01)in comparison with control group, while the expression levels of IL-6, IL-1β, IL-18 and TNF-α wereincreased by 9.53 times, 8.80 times, 10.86 times and 1.17 times, respectively (p<0.01). Meanwhile, the expression levels of key proteins iκB and p65 in NF-κB signaling pathway were significantly increased (p<0.05). Compared to the model group, the activities of SOD and CAT were significantly increased (p＜0.01), while IL-1β, IL-6, TNF-α and IL-18 as well as iκB and p65 were significantly decreased (p<0.05) after PVCP treatment. In conclusion, PVCP could ameliorate cadmium-induced inflammation in RPTEC/TERT1 cells, and its anti-inflammatory effect may be related to antioxidant response and inhibition of NF-κB signaling pathway.
