Anti-inflammatory Effect of Genistein in Human Endometrial Cell Line Treatment with Endotoxin Lipopolysaccharide.

The present study aimed to investigate the anti-inflammatory effect of phytoestrogen genistein (Ge) on the secretion of interleukin 6 (IL6) under lipopolysaccharide (LPS) stimulated conditions in human endometrial epithelial cell line RL95-2. The effects of Ge on expression of TLRs 2, 3, 4 and 9 proteins in response to the inflammatory development induced by LPS were also examined and compared with those of 17β-estradiol (E2).

The RL95-2 cells were cultured in the estrogen-deprived media with or without bacterial endotoxin LPS 30 min prior to incubation with Ge (10-7, 10-6 or 10-5 M) or E2 (10-9 M) for 48 h. The culture media were collected at 1 and 24 h for IL6 measurement by the enzyme linked immunosorbent assay and the cell lysate for TLR protein expression analyzed by semi-quantitative Western blot.

Ge or E2 did not alter the IL6 level in the absence of LPS; however, treatment with either Ge or E2 for 1 h up to 24 h decreased the IL6 level stimulated by LPS. The cells challenged with LPS significantly upregulated the TLRs 2 and 9 but suppressed the TLRs 3 and 4 protein expression. Forty eight h-treatment with Ge had no effect on the TLRs expression, whereas E2 down-regulated the increased TLR9 induced by LPS.

Ge suppressed the inflammatory response by decreasing the IL6 level, but not associated with the alteration of TLRs-mediated pathway inducedby bacterial infection. In contrast, E2 decreased the IL6 secretion possibly due to the opposition on LPS-induced TLR9 expression. This provides the potential evidence of soy isoflavone genistein in alleviating the inflammation of endometrium following bacterial invasion.