Department of Pathology, Xiangya Hospital, Central South University, Changsha, China.
Department of Pathology, School of Basic Medical Science, Central South University, Changsha, China.
Pharm Biol. 2020 Nov 18;58(1):1244-1251. doi: 10.1080/13880209.2020.1851729.
Oral submucous fibrosis (OSF) is a chronic and progressive disease. Arecoline, present in betel nuts, has been proposed as a vital aetiological factor. However, the underlying mechanism remains unclear.
This research elucidates the expression of tropomyosin-1 (TPM1) and its regulation mechanism in HaCaT cells treated with arecoline.
HaCaT cells were assigned into three groups: (1) Control; (2) Treated with arecoline (0.16 mM) for 48 h (3) Treated with arecoline (0.16 mM) and transfected with small interfering RNA (siRNA) for TPM1 (50 nM) for 48 h. CCK8, cell cycle, and apoptosis phenotypic analyses were performed. PCR and western blot analyses were performed to detect the expression level of TPM1 and examine the related signalling pathway.
The IC of arecoline was approximately 50 μg/mL (0.21 mM). The arecoline dose (0.16 mM) and time (48 h) markedly increased TPM1 expression at the mRNA and protein levels in HaCaT cells. Arecoline suppressed the cell growth, caused cell cycle arrest at the G1 phase, and induced cell apoptosis in HaCaT cells. siRNA-mediated knockdown of TPM1 attenuated the effect of arecoline on cell proliferation, apoptosis, and cell cycle arrest at the G1 phase. Furthermore, blocking of the transforming growth factor (TGF)-β receptor using SB431542 significantly suppressed TPM1 expression in the cells treated with arecoline.
Arecoline suppresses HaCaT cell viability by upregulating TPM1 through the TGF-β/Smad signalling pathway. This research provides a scientific basis for further study of arecoline and TPM1 in OSF and can be generalised to broader pharmacological studies. TPM1 may be a promising molecular target for treating OSF.
口腔黏膜下纤维性变（OSF）是一种慢性进行性疾病。槟榔碱存在于槟榔中，被认为是一个重要的病因因素。然而，其潜在机制尚不清楚。
本研究阐明了槟榔碱处理的 HaCaT 细胞中原肌球蛋白-1（TPM1）的表达及其调控机制。
将 HaCaT 细胞分为三组：（1）对照组；（2）用 0.16 mM 槟榔碱处理 48 h（3）用 0.16 mM 槟榔碱和 50 nM TPM1 小干扰 RNA（siRNA）转染处理 48 h。进行 CCK8、细胞周期和凋亡表型分析。进行 PCR 和 Western blot 分析以检测 TPM1 的表达水平，并检查相关信号通路。
槟榔碱的 IC 约为 50μg/mL（0.21 mM）。槟榔碱剂量（0.16 mM）和时间（48 h）显著增加了 HaCaT 细胞中 TPM1 的 mRNA 和蛋白水平表达。槟榔碱抑制细胞生长，导致 HaCaT 细胞周期停滞在 G1 期，并诱导细胞凋亡。siRNA 介导的 TPM1 敲低减弱了槟榔碱对细胞增殖、凋亡和 G1 期细胞周期阻滞的影响。此外，使用 SB431542 阻断转化生长因子（TGF）-β受体显著抑制了槟榔碱处理的细胞中 TPM1 的表达。
槟榔碱通过 TGF-β/Smad 信号通路上调 TPM1 抑制 HaCaT 细胞活力。本研究为进一步研究槟榔碱和 TPM1 在 OSF 中的作用提供了科学依据，并可推广到更广泛的药理学研究。TPM1 可能是治疗 OSF 的有前途的分子靶点。
