Chemotherapeutic drugs can cause reproductive damage by affecting sperm quality and other aspects of male fertility. Stem cells are thought to alleviate the damage caused by chemotherapy drugs and to play roles in reproductive protection and treatment. This study aimed to explore the effects of human umbilical cord mesenchymal stem cells (hUC-MSCs) on alleviating paclitaxel (PTX)-induced spermatogenesis and male fertility defects. An in vivo PTX-induced mice model was constructed to evaluate the reproductive toxicity and protective roles of hUC-MSCs in male fertility improvement. A 14 day PTX treatment regimen significantly attenuated mice spermatogenesis and sperm quality, including affecting spermatogenesis, reducing sperm counts, and decreasing sperm motility. hUC-MSCs treatment could significantly improve sperm functional indicators. Mating experiments with normal female mice and examination of embryo development at 7.5 days post-coitum (dpc) showed that hUC-MSCs restored male mouse fertility that was reduced by PTX. In IVF experiments, PTX impaired sperm fertility and blastocyst development, but hUC-MSCs treatment rescued these indicators. hUC-MSCs’ protective role was also displayed through the increased expression of the fertility-related proteins HSPA2 and HSPA4L in testes with decreased expression in the PTX-treated group. These changes might be related to the PTX-induced decreases in expression of the germ cell proliferation protein PCNA and the meiosis proteins SYCP3, MLH1, and STRA8, which were restored after hUC-MSCs treatment. In the PTX-treated group, the expression of testicular antioxidant proteins SIRT1, NRF2, CAT, SOD1, and PRDX6 was significantly decreased, but hUC-MSCs could maintain these expressions and reverse PTX-related increases in BAX/BCL2 ratios. hUC-MSCs may be a promising agent with antioxidant and anti-apoptosis characteristics that can maintain sperm quality following chemotherapy treatment.

Chemotherapeutic drug of paclitaxel (PTX) has been shown to cause reproductive toxicity thus affecting male fertility, but its underlying molecular basis is unclear. Melatonin (MLT) can mitigate the reproductive damage caused by certain chemotherapy drugs. In this study, we aimed to identify impact of PTX on the main biological processes and protective effect of MLT on reproductive damage caused by PTX. Mice exposed to PTX mainly impaired spermatogenesis, such as decreased sperm counts, reduced sperm motility and increased abnormal sperm. Decreased expressions of germ cell proliferation‐associated protein PCNA and meiosis‐related protein SYCP3 induced by PTX were determined by Western blot, while MLT ameliorated this effect and increased the expressions of PCNA, SYCP3, DMC1, STRA8 and fertility‐related protein of HSPA2, resulting in significantly improved spermatogenesis and sperm quality levels. In vitro fertilization experiment showed that PTX significantly decreased blastocyst formation rates, which can be improved by MLT administration, but not two‐cell development rates. Taken together, this work demonstrated PTX can adversely affect germ cell proliferation and meiosis, which ultimately influence sperm quality and male fertility, and highlighted the protective ability of MLT on ameliorating the side effects of PTX, especially on sperm quality. The results provide information to further the study on the molecular mechanism of PTX's effects on male reproduction and the protective mechanism of MLT.

Doxorubicin (DOX) is an effective chemotherapy drug, but its clinical use has adverse effects on male reproduction. However, there are few studies about the specific biological processes related to male reproduction or strategies for improving fertility protection. In this paper, we examined the effects of DOX on spermatogenesis and sperm function, and tested the possible protective role of melatonin (MLT) against DOX’s reproductive toxicity. DOX-treated mice showed signs of significantly impaired spermatogenesis, including vacuolated epithelial cells, decreased testis weights, and lowered sperm counts and motility. DOX also reduced germ cell proliferation (PCNA) and meiosis-related proteins (SYCP3), but this effect could be partially improved with MLT administration. HSPA2 expression was maintained, which indicated that although MLT did not improve sperm motility, it did have a significant protective effect on elongated sperm. IVF results showed that MLT could partially promote two-cell and blastocyte development that was restricted by DOX. MLT reversed DOX-driven changes in the testes, including the antioxidant indices of SOD1, CAT and PRDX6, and the apoptotic indices of BAX and Caspase3. These results suggest that MLT effectively prevents DOX-induced early reproductive toxicity, and increase our understanding of the molecular mechanisms underlying DOX’s effects on male reproduction and the protective mechanism of MLT.

Allergic rhinitis (AR), which presents symptoms like sneezing and a runny nose, is categorized as an upper respiratory condition of type 2. Recent progress in comprehending AR has revealed the significant role played by type 2 cytokines, specifically interleukin (IL)-13, IL-4, and IL-5. These cytokines are released by helper T cells 2 (Th2) and innate lymphoid cells (ILC2s). ILC2s have the ability to interact with various immune cells and are essential in promoting both type 2 immune response and tissue repair, contributing to normal homeostatic functions within the body. This article presents a summary of the latest advancements in comprehending the activity of ILC2s, with particular emphasis on their potential role involvement in AR. It explores how they collaborate with Th2 cells to exacerbate nasal inflammation and interact with regulatory T cells (Tregs) to counteract the suppressive role mediated by Tregs during allergic inflammation. The significance of ILC2s in allergen-specific therapy is highlighted. A comprehensive understanding of ILC2s biology establishes a robust foundation for unraveling the pathogenesis of AR and devising innovative therapeutic approaches for its management.