Purpose alpha-melanocyte stimulating hormone (α-MSH) is a proopiomelanocortin derivative and a neuropeptide with multi-function, well know for its pigment-inducing capacity, inhibitory action on proinflammatory cytokines and chemoattractant cytokines, and suppression action on collagen synthesis. Our study was to evaluate the effectiveness of α-MSH on proliferation of Human Tenon`s capsule fibroblasts (HTF) stimulated by transforming growth factor β1 (TGF-β1).
Methods Fibroblasts were cultured in Dulbecco’s modified Eagle’s medium (DMEM) in control group, and DMEM with TGF-β1 at concentration of 10-12 M in TGF-β1 group, and DMEM with 10-12 M TGF-β1 and α-MSH ranging from 0, 10–8 M to 10–4 M in TGF-β1/α-MSH groups. Forty eight hours later, cell proliferation was assessed by CellTiter 96 Aqueous One Solution Cell Proliferation Assay. After administration of TGF-β1 at concentration of 10-12 M, or TGF-β1 at 10-12 M plus α-SH at 10-6 M, the mRNA level of type I (α1) collagen, fibronectin, TNF-α, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), MMP-1, MMP-2, TIMP-1, and TIMP-2 in HTF were analyzed using the real time reverse transcription polymerase chain reaction.
Results α-MSH demonstrated inhibitory effect on proliferation of HTF induced by TGF-β1 in a dose-dependent manner when the concentration was lower than 10-5 M, and suppressive effect on the mRNA expression of type I (α1) collagen, TNF-α, ICAM-1 and VCAM-1, which were up-regulated by TGF-β1. Our results showed the reverse effect of α-MSH on the imbalance between MMPs and TIMPs compared with TGF-β1.
Conclusion α-MSH could effectively suppress the HTF proliferation and modulate correlative genes in collagen synthesis stimulated by TGF-β1, which implied that α-MSH could be exploited in the treatment of conjunctival fibrotic scar disorder.
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