Purchase this article with an account.
Toshihiro Inoue, Miyuki Mochita Inoue, Tomokazu Fujimoto, Hidenobu Tanihara; Effects of interleukin-6 signaling activity on fibrogenic activity of human trabecular meshwork cells. Invest. Ophthalmol. Vis. Sci. 2016;57(12):4693.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To examine the effects of interleukin (IL)-6 signaling on transforming growth factor (TGF)-β2–induced fibrogenic activity of human trabecular meshwork (HTM) cells.
Cultured HTM cells, with or without pretreatment with IL-6 (200 ng/ml) and soluble IL-6 receptor (sIL6R; 200 ng/ml), were stimulated with 2.5 ng/ml TGF-β2. The concentration of IL-6 in the culture medium was measured by multiplex immunoassay. The expressions of α-SMA, Smad2, STAT3, MLC2, p38, COL1A2, fibronectin, and their phosphorylation levels were assessed by Western blot analysis. Transcriptional activities of the Smad-binding element were estimated using luciferase reporter assays. Polymerized actin was stained by rhodamine-conjugated phalloidin. Nuclear translocation of Smad2/3 was examined using immunofluorescence microscopy. Statistical differences were calculated using Tukey’s HSD test and P values < 0.05 were considered to indicate statistical significance.
IL-6 concentration in the culture medium was increased from 6.8 pg/ml to 31.3 pg/ml by 24-hour treatment with TGF-β2 (P <0.001). TGF-β2 increased α-SMA expression, actin polymerization, Smad2 promoter activity, and the phosphorylation levels of Smad2, MLC2, and p38 (P < 0.05). These effects were significantly inhibited by IL-6/sIL6R pretreatment accompanied with increase of STAT3 phosphorylation and nuclear translocation (P<0.05). TGF-β2 also increased the expressions of COL1A2 and fibronectin. IL-6/sIL6R pretreatment suppressed the increase of COL1A2 (P), but not fibronectin.
TGF-β2 treatment increased the production of IL-6 from HTM cell. TGF-β2–induced fibrogenic activation was partially suppressed by the activation of IL-6 signaling in HTM cells.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.
This PDF is available to Subscribers Only