Department of Pharmacology, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
School of Life Sciences, Hubei University, Wuhan, 430062, China.
Chemosphere. 2022 Aug;301:134726. doi: 10.1016/j.chemosphere.2022.134726. Epub 2022 Apr 27.
Triphenyltin (TPT) is organotin that is widely used as an anti-fouling agent and has been determined to have male reproductive toxicity. The objective of this study was to investigate the effects of TPT on the testicular microenvironment and sperm quality in male rats. Adult male Sprague Dawley rats were daily gavaged with TPT (0, 0.5, 1, and 2 mg/kg body weight) for 28 days. The results showed that TPT dose-dependently decreased sperm count and sperm motility, interfered with sperm histone-protamine replacement process, and significantly increased sperm deformity rate, but did not affect sperm DNA integrity. TPT at 2 mg/kg significantly decreased the gene and protein expressions of testis PCNA and Ki67, and dose-dependently decreased the number of PCNA-positive cells and Ki67-positive cells. TPT at 1 mg/kg and/or 2 mg/kg down-regulated the expression of StAR, SF1, P450scc, FSHR, WT1, DDX4 and PLZF, and up-regulated SOX9 expression. Simultaneously, TPT reduced serum testosterone levels at each dose and dose-dependently decreased the expression of Leydig cells regulators (INSL3, IGF1, inhibin B) and Sertoli cells regulators (GDNF, FGF2, CXCL12, ETV5), altered testicular microenvironment. Further, in vitro, we treated TM3 (Leydig cells), TM4 (Sertoli cells) and GC-1 (spermatogonia) cells with 1-100 nM TPT for 24 h. 100 nM TPT significantly down-regulated the expression of the above indicators in TM3 and TM4 cells but did not directly affect the cell proliferation ability of GC-1. However, after co-culturing TPT-treated TM3 or TM4 cells with GC-1 cells, it was found that TPT-treated TM3 or TM4 cells dose-dependently reduced the gene and protein expression levels of PCNA and Ki67 and increased cytotoxicity in GC-1 cells. In conclusion, TPT impairs the proliferative ability of spermatogonia by disrupting the microenvironment of Leydig cells and Sertoli cells, which in turn leads to low sperm quality in adult male rats.
三苯基锡（TPT）是一种广泛用作防污剂的有机锡，已被确定具有雄性生殖毒性。本研究的目的是研究 TPT 对雄性大鼠睾丸微环境和精子质量的影响。成年雄性 Sprague Dawley 大鼠每天灌胃 TPT（0、0.5、1 和 2mg/kg 体重）28 天。结果表明，TPT 呈剂量依赖性地降低精子计数和精子活力，干扰精子组蛋白-鱼精蛋白替代过程，显著增加精子畸形率，但不影响精子 DNA 完整性。2mg/kg 的 TPT 显著降低了睾丸 PCNA 和 Ki67 的基因和蛋白表达，并呈剂量依赖性降低了 PCNA 阳性细胞和 Ki67 阳性细胞的数量。1mg/kg 和/或 2mg/kg 的 TPT 下调了 StAR、SF1、P450scc、FSHR、WT1、DDX4 和 PLZF 的表达，并上调了 SOX9 的表达。同时，TPT 降低了各剂量组的血清睾酮水平，并呈剂量依赖性降低了 Leydig 细胞调节剂（INSL3、IGF1、抑制素 B）和 Sertoli 细胞调节剂（GDNF、FGF2、CXCL12、ETV5）的表达，改变了睾丸微环境。此外，在体外，我们用 1-100nM TPT 处理 TM3（Leydig 细胞）、TM4（Sertoli 细胞）和 GC-1（精原细胞）细胞 24h。100nM TPT 显著下调 TM3 和 TM4 细胞中上述指标的表达，但不直接影响 GC-1 细胞的增殖能力。然而，在与 TPT 处理的 TM3 或 TM4 细胞共培养 GC-1 细胞后，发现 TPT 处理的 TM3 或 TM4 细胞呈剂量依赖性地降低了 GC-1 细胞中 PCNA 和 Ki67 的基因和蛋白表达水平，并增加了 GC-1 细胞的细胞毒性。综上所述，TPT 通过破坏 Leydig 细胞和 Sertoli 细胞的微环境，损害精原细胞的增殖能力，从而导致成年雄性大鼠精子质量下降。
