Comparative Pathobiology Group, Cellular and Molecular Pathology Branch, NTP, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, United States.
Toxicol Lett. 2010 Jul 15;196(3):133-41. doi: 10.1016/j.toxlet.2010.03.004. Epub 2010 Mar 15.
Fenvalerate (Fen), widely used for its high insecticidal potency and low mammalian toxicity, is classified as an endocrine-disrupting chemical. Recently, Fen has received great attention for its adverse effects on human reproductive health. In this study, we found that Fen (10 microM) had a stimulatory effect on the growth of both cell lines at 24 h compared with controls by MTS (p < 0.01) and BrdU (p < 0.01) assays in hormonally responsive uterine leiomyoma (UtLM) cells and normal uterine smooth muscle cells (UtSMC). Flow cytometry results showed that Fen enhanced the escape of cells from the G(0)-G(1) checkpoint and promoted progression of both cell types into the S phase. An Annexin V assay showed that Fen had an anti-apoptotic effect on both cell types. By Real-time PCR, we found that collagen I mRNA expression increased (p < 0.05) in Fen-treated cells compared to controls, although it was greater in UtLM tumor cells. Accordingly, Fen increased (p < 0.05) collagen I protein levels in both cell lysate and supernatant when compared to controls. To further test the mechanism of Fen's effects, transactivation and competitive binding assays were done. The results showed Fen did not significantly stimulate luciferase activity at concentrations of 0.1 microM, 1.0 microM or 10.0 microM in either of the cell types. Competitive binding assays revealed that the affinity of Fen binding to estrogen receptors (ERs) was non-detectable compared to E(2). Our data show that Fen can stimulate the growth of both UtLM cells and UtSMC, which involves a combination of enhanced cell cycle progression and inhibition of apoptosis. Also this compound can increase collagen I expression, at both mRNA and protein levels. Interestingly, the ER is less likely involved in either the hyperplasia or extracellular matrix (ECM) overproduction induced by Fen. Our results indicate that Fen exposure could be considered a novel risk factor for uterine fibroids through molecular mechanisms that do not directly involve the ERs.
氰戊菊酯（Fen）因其高效的杀虫活性和低哺乳动物毒性而被广泛使用，被归类为一种内分泌干扰化学物质。最近，Fen 因其对人类生殖健康的不良影响而受到极大关注。在这项研究中，我们发现 Fen（10 μM）在 24 小时通过 MTS（p<0.01）和 BrdU（p<0.01）检测在激素反应性子宫平滑肌瘤（UtLM）细胞和正常子宫平滑肌细胞（UtSMC）中对细胞生长有刺激作用。流式细胞术结果表明，Fen 增强了细胞从 G0-G1 检查点的逃逸，并促进了两种细胞类型进入 S 期。Annexin V 检测表明 Fen 对两种细胞类型均有抗凋亡作用。通过实时 PCR，我们发现与对照组相比，Fen 处理的细胞中胶原 I mRNA 表达增加（p<0.05），尽管 UtLM 肿瘤细胞中的表达更高。因此，与对照组相比，Fen 增加了两种细胞裂解液和上清液中胶原 I 蛋白水平（p<0.05）。为了进一步测试 Fen 作用的机制，进行了转激活和竞争结合测定。结果表明，在两种细胞类型中，浓度为 0.1 μM、1.0 μM 或 10.0 μM 时，Fen 对荧光素酶活性没有显著刺激作用。竞争结合测定显示，与 E2 相比，Fen 与雌激素受体（ERs）结合的亲和力无法检测。我们的数据表明，Fen 可以刺激 UtLM 细胞和 UtSMC 的生长，这涉及到细胞周期进程的增强和凋亡的抑制的组合。此外，该化合物可以增加胶原 I 的表达，无论是在 mRNA 还是蛋白水平上。有趣的是，ER 不太可能参与 Fen 诱导的细胞增生或细胞外基质（ECM）过度产生。我们的结果表明，通过不直接涉及 ER 的分子机制，Fen 暴露可被认为是子宫纤维瘤的一个新的危险因素。
