Oxidative Stress Disrupted Prepubertal Rat Testicular Development after Xenotransplantation

Abstract

In the past two decades, testicular tissue grafting and xenografting have been well established, with the production of fertilization-competent sperm in some studies. However, few studies have been carried out to observe the development of grafted prepubertal testicular tissue of rats and compare the biological differences between in situ testis and grafted testis. In this study, we established the prepubertal testicular tissue xenografting model using a 22-day-old rat and evaluated certain parameters, including testicular histology, testosterone production, and ultrastructure of the grafted testes. We also assessed gene expression of cell proliferation markers, testicular cell markers, and antioxidative defense system. Our results showed that 47 days after transplantation, intratesticular testosterone concentration was not significantly altered; however, cell proliferation, spermatogenesis, and Sertoli cell markers in the transplanted testes were significantly disrupted compared with the control group, accompanied by aggravated apoptosis and oxidative damage. Moreover, the transplanted testes showed smaller tubular diameter and disrupted spermatogenic epithelium with apparent vacuoles, distorted and degenerated germ cells with obscure nuclear margin, and no spermatids in the center of the tubules. Although testis xenografting has been extensively tested and attained great achievement in other species, the prepubertal rat testicular tissue xenografting to immunodeficient mice exhibited obvious spermatogenesis arrest and oxidative damage. The protocol still needs further optimization, and there are still some unknown factors in prepubertal rat testes transplantation.

Immature rat testis sustained long-term development using an integrative model

“…More importantly, the oxidative injuries resulted from oxidation and antioxidant imbalance would also play a role in the formation of vacuoles and thin seminiferous epithelium. Ma reported the phenomenon of apparent vacuoles and oxidative damages after xenotransplantation of prepubertal rat testicular tissue [ 21 ]. Even though some spermatids could be identified in the xenografted testes under fluorescence microscope, there was few spermatids could be observed directly under TEM, which would be related to the vacuolation of Sertoli cells and location of sampling.…”

Yangjing capsule improves oligoasthenozoospermia by promoting nitric oxide production through PLCγ1/AKT/eNOS pathway

“…Testicular histopathology was assessed by hematoxylin and eosin (H&E) staining as previously described ( Ma et al, 2021 ). Briefly, following fixation in Bouin’s solution for 6 h, testes were transferred to ethanol and xylene, embedded in paraffin, and sectioned at a thickness of 5 μm.…”