Combined effects of interleukin-1β and cyclic stretching on metalloproteinase expression in corneal fibroblasts in vitro.
BACKGROUND
Corneal tensile strain increases if the cornea becomes thin or if intraocular pressure increases. However, the effects of mechanical stress on extracellular matrix (ECM) remodelling in the corneal repair process and the corneal anomalies are unknown.


METHODS
In this study, the combined effects of interleukin-1β (IL-1β) on matrix metalloproteinases (MMPs) in corneal fibroblasts under cyclic stretching were investigated in vitro. Cultured rabbit corneal fibroblasts were subjected to 5, 10 or 15 % cyclic equibiaxial stretching at 0.1 Hz for 36 h in the presence of IL-1β. Conditioned medium was harvested for the analysis of MMP2 and MMP9 protein production using the gelatin zymography and western blot techniques.


CONCLUSIONS
Cyclic equibiaxial stretching changed the cell morphology by increasing the contractility of F-actin fibres. IL-1β alone induced the expression of MMP9 and increased the production of MMP2, and 5 % stretching alone decreased the production of MMP2, which indicates that a low stretching magnitude can reduce ECM degradation. In the presence of IL-1β, 5 and 10 % stretching increased the production of MMP2, whereas 15 % stretching increased the production of MMP9. These results indicate that MMP expression is enhanced by cyclic mechanical stimulation in the presence of IL-1β, which is expected to contribute to corneal ECM degradation, leading to the development of post-refractive surgery keratectasia.
Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
Pengfei
P
Feng
Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China. lixiaona@tyut.edu.cn.
Xiaona
X
Li
Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China. chenweiyi211@163.com.
Weiyi
W
Chen
Biology Department, Taiyuan Normal University, Jinzhong, 030619, China.
Chengxing
C
Liu
Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
Shuo
S
Rong
College of Mechanics, Taiyuan University of Technology, Taiyuan, 030024, China.
Xiaojun
X
Wang
Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
Genlai
G
Du
D000818:Animals; D001696:Biomechanical Phenomena; D003315:Cornea / Q000166:cytology*; D004792:Enzyme Precursors / Q000096:biosynthesis / Q000378:metabolism; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D006801:Humans; D053583:Interleukin-1beta / Q000494:pharmacology*; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis / Q000378:metabolism*; D055595:Mechanical Phenomena; D011817:Rabbits
D004792:Enzyme Precursors; D053583:Interleukin-1beta; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9
Corneal fibroblasts; Cyclic stretching; Interleukin-1β; Matrix metalloproteinases