周期性张拉力作用下人成纤维细胞早期成骨过程中整合素 αVβ3-肌动蛋白丝轴的调控。

Regulation of the integrin αVβ3- actin filaments axis in early osteogenesis of human fibroblasts under cyclic tensile stress.

机构信息

Guangdong Provincial Key Laboratory of Medical Biomechanics and Department of Anatomy, School of Basic Medical Science, Southern Medical University, Guangzhou, 510000, China.

Department of Ophthalmology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510000, Guangdong, China.

出版信息

Stem Cell Res Ther. 2021 Oct 7;12(1):523. doi: 10.1186/s13287-021-02597-y.

BACKGROUND

Integrins play a prominent role in osteogenic differentiation by transmitting both mechanical and chemical signals. Integrin expression is closely associated with tensile stress, which has a positive effect on osteogenic differentiation. We investigated the relationship between integrin αVβ3 and tensile stress.

METHODS

Human fibroblasts were treated with c (RGDyk) and lentivirus transduction to inhibit function of integrin αVβ3. Y-15, cytochalasin D and verteporfin were used to inhibit phosphorylation of FAK, polymerization of microfilament and function of nuclear YAP, respectively. Fibroblasts were exposed to a cyclic tensile stress of 10% at 0.5 Hz, once a day for 2 h each application. Fibroblasts were harvested on day 4 and 7 post-treatment. The expression of ALP, RUNX2, integrin αVβ3, β-actin, talin-1, FAK, vinculin, and nuclear YAP was detected by Western blot or qRT-PCR. The expression and distribution of integrin αVβ3, vinculin, microfilament and nuclear YAP.

RESULTS

Cyclic tensile stress was found to promote expression of ALP and RUNX2. Inhibition of integrin αVβ3 activation downregulated the rearrangement of microfilament and the expression of ALP, RUNX2 and nuclear YAP. When the polymerization of microfilament was inhibited the expression of ALP, RUNX2 and nuclear YAP were decreased. The phosphorylation of FAK induced by cyclic tensile stress reduced by the inhibition of integrin αVβ3. The expression of ALP and RUNX2 was decreased by inhibition of phosphorylation of FAK and inhibition of nuclear YAP.

CONCLUSIONS

Cyclic tensile stress promotes osteogenesis of human fibroblasts via integrin αVβ3-microfilament axis. Phosphorylation of FAK and nuclear YAP participates in this process.

背景

整合素在骨生成分化中起着重要作用，它既能传递机械信号，又能传递化学信号。整合素的表达与张应力密切相关，张应力对成骨分化有积极影响。我们研究了整合素 αVβ3 与张应力的关系。

方法

用 c（RGDyk）和慢病毒转导处理人成纤维细胞，以抑制整合素 αVβ3 的功能。用 Y-15、细胞松弛素 D 和维替泊芬分别抑制 FAK 磷酸化、微丝聚合和核 YAP 的功能。每天一次，将成纤维细胞暴露于 0.5 Hz、10%的循环张应力下，每次应用 2 小时。处理后第 4 天和第 7 天收获成纤维细胞。用 Western blot 或 qRT-PCR 检测碱性磷酸酶（ALP）、RUNX2、整合素 αVβ3、β-肌动蛋白、talin-1、FAK、 vinculin 和核 YAP 的表达。检测整合素 αVβ3、vinculin、微丝和核 YAP 的表达和分布。

结果

循环张应力促进了 ALP 和 RUNX2 的表达。整合素 αVβ3 激活的抑制降低了微丝的重排和 ALP、RUNX2 和核 YAP 的表达。当微丝聚合被抑制时，ALP、RUNX2 和核 YAP 的表达减少。整合素 αVβ3 抑制导致循环张应力诱导的 FAK 磷酸化减少。FAK 磷酸化和核 YAP 抑制抑制 ALP 和 RUNX2 的表达。