Comparative effects of estrogen on matrix metalloproteinases and cytokines in immortalized and primary human corneal epithelial cell cultures.

PURPOSE

Recently, we found that 17beta-estradiol induces cytokine and MMP gene expression in SV40 immortalized human corneal epithelial cells (SV40 HCEs). The purpose of this study was to determine if 17beta-estradiol stimulates MMP secretion by cultures of SV40 HCEs and primary human corneal epithelial cells. Further, we determined if estrogen influenced cytokine and MMP gene expression in the primary cultures.

METHODS

Gelatin zymography was used to identify MMP-2 and MMP-9 gelatinase activity in the culture medium from SV40 HCEs and primary human corneal epithelial cell cultures exposed to vehicle or 17beta-estradiol for 6 or 24 hour. In addition, 17beta-estradiol effects on cytokine and MMP gene expression in primary cultures were evaluated by real-time PCR methods.

RESULTS

17beta-estradiol had no significant effects on MMP activity in the culture media of either SV40 HCEs or primary corneal epithelial cell cultures. SV40 HCEs secreted predominantly MMP-2, whereas the primary cultures secreted predominantly MMP-9. In primary cultures, 17beta-estradiol caused a significant decrease of IL-6 and IL-8 gene expression, but had no effect on the levels of IL-1beta, MMP-2, and MMP-9 gene expression.

CONCLUSIONS

Our findings suggest that 17beta-estradiol effects on gelatinase gene expression in SV40 HCEs are not translated into changes in secreted MMP activity. Estrogen influences on gene expression of cytokine and MMPs in primary cultures are different from those in SV40 HCEs.