他汀类药物通过抑制 RhoA/ROCK 抑制人视神经头部星形细胞中 TGF-β2 介导的 MMP-2 和 MMP-9 的表达和激活。

PURPOSE

Matrix metalloproteinases (MMPs) are involved in extracellular matrix (ECM) maintenance and remodeling. The present study aimed to determine whether transforming growth factor (TGF)-β2 regulates MMP-2 and MMP-9 levels and activities in astrocytes derived from the optic nerve head (ONH) and the role of statins in such modulation.

METHODS

Primary astrocytes cultured from the lamina cribrosa of human donor ONHs were incubated with three types of statins (5 µg/mL) for 1 hour followed by recombinant TGF-β2 (5 ng/mL) for various periods to test their effects. Levels and activities of MMP-2 and MMP-9 in astrocytes in vitro were determined by western blotting and zymography, respectively. Levels of phosphorylated myosin phosphatase target subunit 1 (MYPT1) in astrocyte lysates were determined by western blotting, and those of phosphorylated myosin light chain (MLC) were determined by western blotting and immunocytochemistry.

RESULTS

MMP-2 and MMP-9 levels were upregulated by TGF-β2 in human ONH astrocytes. Prior incubation with simvastatin, lovastatin, and atorvastatin inhibited TGF-β2-mediated MMP-2 and MMP-9 expression and activities. Prior incubation with statins downregulated the TGF-β2-induced phosphorylation of MYPT1 and MLC, which are downstream substrates of RhoA and ROCKs.

CONCLUSIONS

Statins inhibited the TGF-β2-mediated regulation of MMP-2 and MMP-9 by inhibiting the RhoA/ROCK signaling pathway. Considering the role of MMP in ECM remodeling, the present findings support the notion that statins positively impact ECM remodeling within the ONH.

目的

基质金属蛋白酶（MMPs）参与细胞外基质（ECM）的维持和重塑。本研究旨在确定转化生长因子（TGF）-β2 是否调节视神经头（ONH）来源的星形胶质细胞中 MMP-2 和 MMP-9 的水平和活性，以及他汀类药物在这种调节中的作用。

方法

用三种他汀类药物（5μg/ml）孵育来自人供体 ONH 节细胞层的原代星形胶质细胞 1 小时，然后用重组 TGF-β2（5ng/ml）孵育不同时间，以测试其作用。通过 Western blot 和明胶酶谱法分别测定星形胶质细胞中 MMP-2 和 MMP-9 的水平和活性。通过 Western blot 测定星形胶质细胞裂解物中磷酸化肌球蛋白磷酸酶靶亚单位 1（MYPT1）的水平，通过 Western blot 和免疫细胞化学测定磷酸化肌球蛋白轻链（MLC）的水平。

结果

TGF-β2 上调人 ONH 星形胶质细胞中 MMP-2 和 MMP-9 的水平。预先用辛伐他汀、洛伐他汀和阿托伐他汀孵育可抑制 TGF-β2 介导的 MMP-2 和 MMP-9 表达和活性。他汀类药物预先孵育可下调 TGF-β2 诱导的 MYPT1 和 MLC 磷酸化，后者是 RhoA 和 ROCKs 的下游底物。