Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China.
Department of Pulmonary and Critical Care Medicine, The Third Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China.
Adv Med Sci. 2023 Sep;68(2):186-194. doi: 10.1016/j.advms.2023.04.002. Epub 2023 May 4.
Current medical treatment for asthma aims to inhibit airway smooth muscle (ASM) contraction and proliferation, however, the efficacy of available treatment options is unsatisfactory. Therefore, we explored the effect of LIM domain kinase (LIMK) inhibitor - LIMKi3, on ASM to improve the understanding of ASM contraction and proliferation mechanisms, and to investigate new therapeutic targets.
Asthma model was induced in rats by intraperitoneal injection of ovalbumin. Using phospho-specific antibodies, we examined LIMK, phosphorylated LIMK, cofilin and phosphorylated cofilin. ASM contraction was studied in organ bath experiments. ASM cells proliferation was studied with cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays.
Immunofluorescence indicated that LIMKs are expressed in ASM tissues. Western blot revealed that LIMK1 and phospho-cofilin were significantly elevated in asthma ASM tissues. The LIMK inhibitor, LIMKi3 (1 μM) could reduce cofilin phosphorylation and therefore inhibit contraction of ASM tissues, and induce actin filament breakdown as well as cell proliferation reduction in cultured human ASM cells.
ASM contraction and proliferation in asthma may underlie the effects of LIMKs. Small molecule LIMK inhibitor, LIMKi3, might be a potential therapeutic strategy for asthma.
目前哮喘的治疗方法旨在抑制气道平滑肌（ASM）收缩和增殖，然而，现有治疗选择的疗效并不令人满意。因此，我们探索了 LIM 结构域激酶（LIMK）抑制剂-LIMKi3 对 ASM 的作用，以加深对 ASM 收缩和增殖机制的理解，并研究新的治疗靶点。
通过腹腔注射卵清蛋白诱导大鼠哮喘模型。使用磷酸化特异性抗体，我们检测了 LIMK、磷酸化 LIMK、丝切蛋白和磷酸化丝切蛋白。在器官浴实验中研究 ASM 收缩。通过细胞计数试剂盒-8（CCK-8）和 5-乙炔基-2'-脱氧尿苷（EdU）测定研究 ASM 细胞增殖。
免疫荧光表明 LIMKs 表达于 ASM 组织中。Western blot 显示，哮喘 ASM 组织中 LIMK1 和磷酸化丝切蛋白明显升高。LIMK 抑制剂 LIMKi3（1 μM）可减少丝切蛋白磷酸化，从而抑制 ASM 组织收缩，并诱导培养的人 ASM 细胞中的肌动蛋白丝断裂和细胞增殖减少。
哮喘中 ASM 的收缩和增殖可能是 LIMKs 的作用机制。小分子 LIMK 抑制剂 LIMKi3 可能是哮喘的潜在治疗策略。
