Histological and ultrastructural changes observed in testicles, epididymides, seminal vesicles and liver of rat after intraperitoneal administration of aluminum and indium

Nicotinamide Mononucleotide Improves Spermatogenic Disorders in Aluminum-Exposed Rats by Modulating the Glycolytic Pathway

This study aimed to investigate the protective effect of nicotinamide mononucleotide (NMN) on testicular spermatogenesis in aluminum chloride (AlCl3)-exposed rats and to elucidate the potential underlying mechanism. The results indicated that AlCl3-induced testicular damage, leading to reduced sperm quality, increased apoptosis, decreased cell proliferation, and impaired Sertoli cell function in rats. Additionally, glycolytic metabolism was observed to be hindered. However, after NMN treatment, there was a noticeable improvement in testicular damage among the rats, marked by increased sperm quality, reduced apoptosis, enhanced cell proliferation, improved Sertoli cell function, and an activated glycolytic metabolism. The findings of this study suggest that NMN alleviates testicular spermatogenesis impairment induced by AlCl3 exposure through the inhibition of spermatogenic cell apoptosis, promotion of spermatogenic cell proliferation, and activation of glycolytic pathways. The study contributes an experimental foundation for potential future clinical applications of NMN in cases of AlCl3-exposed spermatogenic dysfunction.

Reactive Oxygen Species-Mediated Mitophagy and Cell Apoptosis are Involved in the Toxicity of Aluminum Chloride Exposure in GC-2spd

Aluminum chloride is an inorganic polymeric coagulant commonly found in daily life and various materials. Although male reproductive toxicity has been associated with AlCl3 exposure, the underlying mechanism remains unclear. This study aimed to examine the impact of AlCl3 exposure on mitophagy and mitochondrial apoptosis in testicular tissue and mouse spermatocytes. Reactive oxygen species (ROS) and ATP levels were measured in GC-2spd after AlCl3 exposure using a multifunctional enzyme labeler. The changes in mitochondrial membrane potential (MMP) and TUNEL were observed through confocal laser microscopy, and the expression of proteins associated with mitophagy and apoptosis was analyzed using Western blot. Our results demonstrated that AlCl3 exposure disrupted mitophagy and increased apoptosis-related protein expression in testicular tissues. In the in vitro experiments, AlCl3 exposure induced ROS production, suppressed cell viability and ATP production, and caused a decrease in MMP, leading to mitophagy and cell apoptosis in GC-2spd cells. Intervention with N-acetylcysteine (NAC) reduced ROS production and partially restored mitochondrial function, thereby reversing the resulting mitophagy and cell apoptosis. Our findings provide evidence that ROS-mediated mitophagy and cell apoptosis play a crucial role in the toxicity of AlCl3 exposure in GC-2spd. These results contribute to the understanding of male reproductive toxicity caused by AlCl3 exposure and offer a foundation for future research in this area.

Aluminum exposure impairs oocyte quality via subcellular structure disruption and DNA damage-related apoptosis in mice

Aluminum (Al) can lead to an exposure of creature in varieties ways for its universality, and it could disturb normal physiological metabolism, with the damage to multisystem including reproduction. Since the oocyte quality is critical for female reproduction, we inspected the toxicity of Al on mouse oocyte maturation. We constructed in vitro exposure mouse model, and we found that 5 mmol/L Al had adverse effects on oocyte maturation by impairing organelle and cytoskeleton. Aberrant spindle and misaligned chromosomes which might be considered to be caused by elevated levels of acetylation, as well as abnormal distribution of actin dynamics could hinder normal meiosis of oocytes. Organelle dysfunction indicated that Al affected proteins synthesis, transport and digestion, which would further damage oocyte maturation. In order to explore the mechanism of Al toxicity, our further investigation demonstrated that Al caused mitochondrial dysfunction and imbalance calcium homeostasis, resulting in limited energy supply. Moreover, high level of reactive oxygen species, DNA damage and apoptosis caused by oxidative stress were also the manifestation of Al toxicity on oocytes. In conclusion, our study provided the evidence that Al exposure affected oocyte quality through its effects on spindle organization, actin dynamics, organelle function and the induction of DNA damage-related apoptosis with mouse model.

Galaxolide and Irgacure 369 are novel environmental androgens

Endocrine disruptors are environmental chemicals that can interfere with the endocrine system. However, research on endocrine disruptors that interfere with androgen's actions is still limited. The purpose of this study is to use in silico computation, i.e., molecular docking to facilitate the identification of environmental androgens. Computational docking was used to study the binding interactions of environmental/industrial compounds with the three dimensional structure of human androgen receptor (AR). Then reporter assay and cell proliferation assay using AR-expressing LNCaP prostate cancer cells were used to determine their in vitro androgenic activity. Animal studies using immature male rats were also carried out to test their in vivo androgenic activity. Two novel environmental androgens were identified. As a photoinitiator, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone (Irgacure 369, abbreviated as IC-369) is widely used in the packaging and electronics industries. Galaxolide (HHCB) is widely used in the production of perfume, fabric softeners and detergents. We found that both IC-369 and HHCB could activate AR transcriptional activity and promote cell proliferation in AR-sensitive LNCaP cells. Furthermore, IC-369 and HHCB could induce cell proliferation and histological changes of seminal vesicles in immature rats. RNA sequencing and qPCR analysis showed that androgen-related genes in seminal vesicle tissue were up-regulated by IC-369 and HHCB. In conclusion, IC-369 and HHCB are new environmental androgens that bind AR and induce AR transcriptional activity, thereby exerting toxicological effects on the development of male reproductive organs.