The effects of genistein on estrogen receptor-β, IL-1β levels, and MUC5AC expression in ovariectomized rats with dry eye

The purpose of this study was to investigate the effects of genistein on estrogen receptor-β (ER-β) expression, IL-1β expression, and MUC5AC expression in post-menopausal dry eye syndrome model rat. A total of thirty female rats were divided into five study groups, consisting of control group (without any treatment), the dry-eye rat model group, the dry-eye rat model treated with various doses of topical genistein (50 μM, 100 μM, and 200 μM). The ER-β, IL-1β, and MUC-5AC expressions were evaluated by immunofluorescence (confocal laser scanning microscopy). The ER-β expression decreased significantly in the dry eye model group compared with the control group (p < 0.05), this decrease could be inhibited by all doses of genistein, but not yet achieved an expression comparable to the control group (p < 0.05). MUC5AC expression was significantly lower in the dry eye model compared with the control group (p < 0.05), this reduction could be increased by all groups treated with genistein, achieving values comparable to the control group for the groups treated with genistein of second and third doses (p > 0.05). The IL-1β levels in the dry eye model group were significantly higher than the control group (p < 0.05). This increase can be decreased by the administration of third-dose genistein. It was concluded that genistein can suppress IL-1β levels production and may trigger upregulation of ER-β and MUC5AC expression in the dry eye model due to ovariectomy. Thus, genistein may become an alternative to suppress inflammation and mucin production in dry eye syndrome.