Zinc Deficiency Leads to Reproductive Impairment in Male Mice Through Imbalance of Zinc Homeostasis and Inflammatory Response.

Abstract

Zinc is an essential trace element crucial for growth and development and plays a significant role in male reproductive function. The aim of this study was explore the mechanism of male reproductive damage caused by different degrees of zinc deficiency. Thirty male ICR mice were randomly assigned to three groups: zinc-normal diet group (ZN, n = 10, Zn content = 30 mg/kg), low zinc-deficiency diet group (LZD, n = 10, Zn content = 15 mg/kg), and high zinc-deficiency diet group (HZD, n = 10, Zn content = 7.5 mg/kg). The mice were maintained for 8 weeks. At the end of the experiment, they were sacrificed, and their blood, testicular, and epididymal tissues were collected for further study. Zinc-deficient diet led to weight loss, testicular structural disorder, decreased semen quality, imbalance of zinc homeostasis, and inflammatory damage in mice. Semen quality, testosterone, serum Zn, testicular tissue Zn, testicular free Zn ions, Zrt-, Irt-like protein8 (ZIP8), Zrt-, Irt-like protein5 (ZIP5), and interleukin-10 (IL-10) were significantly decreased; zinc transporter 4(ZnT4), NF-κB p65, P-NF-κB p65, NLRP3, Caspase-8, and Caspase-3 were significantly increased in both LZD and HZD group mice. While compared with the LZD group, Zrt-, Irt-like protein13 (ZIP13), TNF-α, NF-κB p65, P-NF-κB p65, NLRP3, Caspase-1, and GSDMD were significantly increased in the HZD group. Both low and high zinc-deficiency diets can disrupt zinc homeostasis in mice, leading to heightened inflammatory responses, the activation of the NF-κB pathway, and increased apoptosis in testicular cells. Notably, a high zinc-deficiency diet led to an up-regulation of ZIP13 expression, exacerbated inflammation, and induced testicular pyroptosis, resulting in more severe reproductive damage in male mice.