Encephalopathy Center, The First Affiliated Hospital, Anhui University of Traditional Chinese Medicine, Hefei, China.
Reproductive and Genetic Branch, The First Affiliated Hospital of University of Science and Technology of China (USTC), Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
Front Endocrinol (Lausanne). 2022 Aug 5;13:961748. doi: 10.3389/fendo.2022.961748. eCollection 2022.
Wilson's disease (WD) is an autosomal recessive disorder of copper metabolism characterized by liver and central nervous system dysfunction. Considerable evidence suggests that infertility is also very common in male patients with WD, but the exact molecular mechanisms involved remain unknown. In order to further investigate the pathological changes in the hypothalamic-pituitary-testicular (HPT) axis and its mechanisms, mice were divided into the normal control group (NC), WD model TX mice group (WD), dimercaptosuccinic acid-treated TX mice group (DMSA), and pregnant horse serum gonadotropin-treated TX mice group (PMSG). The copper content and morphology of hypothalamus and pituitary tissues, the ultrastructure and apoptosis of hypothalamus neurons and pituitary gonadotropin cells, the serum levels of reproductive hormones, and the pregnancy rate and litter size of the female mice were studied. The expression of apoptosis-related proteins and the phosphorylation of extracellular regulatory protein kinase (ERK) 1/2 in the hypothalamus and pituitary were detected. The results showed that the copper content was significantly increased in the WD group, and the histopathological morphology and ultrastructure of the hypothalamus and pituitary were damaged. The levels of the gonadotropin-releasing hormone, the follicle-stimulating hormone, the luteinizing hormone, and testosterone were significantly decreased. The apoptosis rate in the hypothalamus and pituitary was significantly increased. The expressions of proapoptotic proteins Bax and Caspase-3 were significantly increased, the expression of the anti-apoptotic protein Bcl-2 was significantly decreased, and the phosphorylation level of ERK1/2 was significantly decreased. Fertility is significantly reduced. After DMSA intervention, the hypothalamus tissue copper content decreased, the hypothalamus and pituitary tissue morphology and ultrastructure were improved, cell apoptosis was alleviated, the expression of Bax and Caspase-3 was significantly decreased, the expression of Bcl-2 was significantly increased, and the reproductive hormone level, phosphorylation level, and fertility were increased. Fertility was preserved after treatment with PMSG in male TX mice. These results suggest that copper deposition in WD causes male fertility decline by impairing reproductive neuroendocrine hormone release through inducing apoptosis and inhibiting the ERK signal in the hypothalamic-pituitary region. This study can also provide reference for the damage of copper pollution to the male reproductive system.
威尔逊病 (WD) 是一种常染色体隐性遗传性铜代谢疾病，其特征为肝脏和中枢神经系统功能障碍。大量证据表明，男性 WD 患者也普遍存在不育问题，但具体的分子机制尚不清楚。为了进一步研究下丘脑-垂体-睾丸 (HPT) 轴的病理变化及其机制，将小鼠分为正常对照组 (NC)、WD 模型 TX 小鼠组 (WD)、二巯丁二酸处理 TX 小鼠组 (DMSA) 和孕马血清促性腺激素处理 TX 小鼠组 (PMSG)。研究了下丘脑和垂体组织的铜含量和形态、下丘脑神经元和垂体促性腺激素细胞的超微结构和凋亡、生殖激素的血清水平以及雌性小鼠的妊娠率和产仔数。检测了下丘脑和垂体中凋亡相关蛋白的表达以及细胞外调节蛋白激酶 (ERK) 1/2 的磷酸化。结果表明，WD 组铜含量明显增加，下丘脑和垂体的组织学形态和超微结构受损。促性腺激素释放激素、卵泡刺激素、黄体生成素和睾酮水平明显降低。下丘脑和垂体的凋亡率明显增加。促凋亡蛋白 Bax 和 Caspase-3 的表达明显增加，抗凋亡蛋白 Bcl-2 的表达明显减少，ERK1/2 的磷酸化水平明显降低。生育能力明显降低。经 DMSA 干预后，下丘脑组织铜含量降低，下丘脑和垂体组织形态和超微结构改善，细胞凋亡减轻，Bax 和 Caspase-3 的表达明显降低，Bcl-2 的表达明显增加，生殖激素水平、磷酸化水平和生育能力均有所提高。雄性 TX 小鼠经 PMSG 治疗后生育能力得到保存。这些结果表明，WD 中的铜沉积通过诱导下丘脑-垂体区域的细胞凋亡和抑制 ERK 信号，导致生殖神经内分泌激素释放受损，从而导致男性生育能力下降。本研究也可为铜污染对男性生殖系统的损伤提供参考。
