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Toxicology Reports Jun 2024Assessing toxicity of complex mixtures of contaminants from industrial sites with historic and ongoing contamination remains a challenge for risk assessors. Groundwater...
Assessing toxicity of complex mixtures of contaminants from industrial sites with historic and ongoing contamination remains a challenge for risk assessors. Groundwater from a pesticide packaging site in Canada containing a complex mixture of known and unknown contaminants was examined in male rats to determine the target organ toxicity. This study determined the time-course of toxicity (7, 14, 28, and 60 days) following oral exposure to 0.05% v/v contaminated groundwater compared to tap water (control) in male Sprague Dawley rats (n=5 /group/time). Exposure to groundwater resulted in inflammation, indicated by a statistically significant increase in plasma lymphocyte and neutrophil counts on days 7 and 60, respectively, but a reduction in the plasma alpha 2 macroglobulin levels by day 60. Gonadotoxicity was indicated by a reduced Johnsen score (grading spermatogenesis) in all exposed groups at all time points, while seminiferous epithelial height was reduced on days 7, 14, and 28 compared to controls. Plasma testosterone was reduced in exposed groups on days 7 and 28, accompanied by elevated testicular lipid peroxidation at all time points compared to control. In contrast, lipid peroxidation in the lungs from exposed rats was elevated on days 7, 14, and 28. Plasma symmetric dimethylarginine was elevated on day 14 in the exposed group indicating renal impairment. Taken together, these results indicate that testes, kidney, immune and lung are target organs for the contaminated groundwater from this industrial site. The current study highlights the challenge in hazard assessment for complex mixtures and highlights the need for effects-directed analysis and the continued, albeit limited, use of animal models in toxicity testing.
PubMed: 38813463
DOI: 10.1016/j.toxrep.2024.05.002 -
Brazilian Journal of Medical and... 2024Adenine nucleotide translocator 4 (Ant4), an ATP/ADP transporter expressed in the early phases of spermatogenesis, plays a crucial role in male fertility. While Ant4...
Adenine nucleotide translocator 4 (Ant4), an ATP/ADP transporter expressed in the early phases of spermatogenesis, plays a crucial role in male fertility. While Ant4 loss causes early arrest of meiosis and increased apoptosis of spermatogenic cells in male mice, its other potential functions in male fertility remain unexplored. Here, we utilized Ant4 knockout mice to delineate the effects of Ant4-deficiency on male reproduction. Our observations demonstrated that Ant4-deficiency led to infertility and impaired testicular development, which was further investigated by evaluating testicular oxidative stress, autophagy, and inflammation. Specifically, the loss of Ant4 led to an imbalance of oxidation and antioxidants. Significant ultrastructural alterations were identified in the testicular tissues of Ant4-deficient mice, including swelling of mitochondria, loss of cristae, and accumulation of autophagosomes. Our results also showed that autophagic flux and AKT-AMPK-mTOR signaling pathway were affected in Ant4-deficient mice. Moreover, Ant4 loss increased the expression of pro-inflammatory factors. Overall, our findings underscored the importance of Ant4 in regulating oxidative stress, autophagy, and inflammation in testicular tissues. Taken together, these insights provided a nuanced understanding of the significance of Ant4 in testicular development.
Topics: Animals; Male; Mice, Knockout; Testis; Oxidative Stress; Mitochondrial ADP, ATP Translocases; Mice; Autophagy; Infertility, Male; Spermatogenesis; Apoptosis; Signal Transduction
PubMed: 38808891
DOI: 10.1590/1414-431X2024e13590 -
ELife May 2024is a powerful model to study how lipids affect spermatogenesis. Yet, the contribution of neutral lipids, a major lipid group which resides in organelles called lipid...
is a powerful model to study how lipids affect spermatogenesis. Yet, the contribution of neutral lipids, a major lipid group which resides in organelles called lipid droplets (LD), to sperm development is largely unknown. Emerging evidence suggests LD are present in the testis and that loss of neutral lipid- and LD-associated genes causes subfertility; however, key regulators of testis neutral lipids and LD remain unclear. Here, we show LD are present in early-stage somatic and germline cells within the testis. We identified a role for triglyceride lipase () in regulating testis LD, and found that whole-body loss of leads to defects in sperm development. Importantly, these represent cell-autonomous roles for in regulating testis LD and spermatogenesis. Because lipidomic analysis of mutants revealed excess triglyceride accumulation, and spermatogenic defects in mutants were rescued by genetically blocking triglyceride synthesis, our data suggest that -mediated regulation of triglyceride influences sperm development. This identifies triglyceride as an important neutral lipid that contributes to sperm development, and reveals a key role for in regulating testis triglyceride levels during spermatogenesis.
Topics: Spermatogenesis; Animals; Male; Triglycerides; Drosophila Proteins; Testis; Drosophila melanogaster; Lipase; Lipid Droplets; Spermatozoa
PubMed: 38805376
DOI: 10.7554/eLife.87523 -
JBRA Assisted Reproduction May 2024Methotrexate (MTX) is widely administered for the treatment of various cancers. However, MTX induces male reproductive toxicity. In the current study, the effect of...
OBJECTIVE
Methotrexate (MTX) is widely administered for the treatment of various cancers. However, MTX induces male reproductive toxicity. In the current study, the effect of ozone therapy (OT) on reducing the toxic effects of MTX in the mouse testicles has been investigated.
METHODS
Twenty-four mice were divided into four groups: control, OT (4 mg/kg ozone), MTX (20 mg/kg), and MTX + OT. Testosterone levels, histological changes, and oxidative stress biomarkers were assessed to evaluate the protective effects of OT.
RESULTS
The results demonstrated that MTX disrupted germinal epithelium, reduced serum testosterone levels, and enhanced oxidative stress in testicular tissue. However, treatment with OT attenuated these adverse effects. OT effectively restored the levels of antioxidant enzymes, such as catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD). OT reduced lipid peroxidation, as indicated by decreased malondialdehyde (MDA) levels. OT preserved normal spermatogenesis, improved morphometric parameters, and reduced histological changes by MTX. Moreover, OT effectively restored testosterone levels.
CONCLUSIONS
OT protects against MTX-induced testicular damage by suppressing oxidative stress.
PubMed: 38801315
DOI: 10.5935/1518-0557.20240041 -
PeerJ 2024Circular RNAs (circRNAs) are a large class of RNAs present in mammals. Among these, is a well-acknowledged circRNA with significant implications, particularly in the...
BACKGROUND
Circular RNAs (circRNAs) are a large class of RNAs present in mammals. Among these, is a well-acknowledged circRNA with significant implications, particularly in the development and progression of diverse tumors. However, the potential consequences of depletion on male reproduction are yet to be thoroughly investigated.
METHODS
The presence of in the mouse testes was confirmed, and gene expression analysis was performed using reverse transcription quantitative polymerase chain reaction. knockout mice were generated utilizing the CRISPR/Cas9 system. Phenotypic analysis of both the testes and epididymis was conducted using histological and immunofluorescence staining. Additionally, fertility and sperm motility were assessed.
RESULTS
Here, we successfully established a knockout mouse model without affecting the expression of parental gene. Surprisingly, male mice lacking () exhibited normal fertility, with no discernible differences in testicular and epididymal histology, spermatogenesis, sperm counts or sperm motility compared to mice. These findings suggest that may not play an essential role in physiological spermatogenesis. Nonetheless, this result also underscores the complexity of circRNA function in male reproductive biology. Therefore, further research is necessary to elucidate the precise roles of other circRNAs in regulating male fertility.
Topics: Animals; Male; RNA, Circular; Mice, Knockout; Fertility; Mice; Testis; Sperm Motility; Spermatogenesis; Epididymis
PubMed: 38799061
DOI: 10.7717/peerj.17399 -
Journal of Translational Medicine May 2024As a key factor in determining testis size and sperm number, sertoli cells (SCs) play a crucial role in male infertility. Heat stress (HS) reduces SCs counts, negatively...
As a key factor in determining testis size and sperm number, sertoli cells (SCs) play a crucial role in male infertility. Heat stress (HS) reduces SCs counts, negatively impacting nutrient transport and supply to germ cells, and leading to spermatogenesis failure in humans and animals. However, how HS affects the number of SCs remains unclear. We hypothesized that changes in SC metabolism contribute to the adverse effects of HS. In this study, we first observed an upregulation of arachidonic acid (AA), an unsaturated fatty acid after HS exposure by LC-MS/MS metabolome detection. By increasing ROS levels, expression of KEAP1 and NRF2 proteins as well as LC3 and LAMP2, 100 µM AA induced autophagy in SCs by activating oxidative stress (OS). We observed adverse effects of AA on mitochondria under HS with a decrease of mitochondrial number and an increase of mitochondrial membrane potential (MMP). We also found that AA alternated the oxygen transport and absorption function of mitochondria by increasing glycolysis flux and decreasing oxygen consumption rate as well as the expression of mitochondrial electron transport chain (ETC) proteins Complex I, II, V. However, pretreatment with 5 mM NAC (ROS inhibitor) and 2 µM Rotenone (mitochondrial ETC inhibitor) reversed the autophagy induced by AA. In summary, AA modulates autophagy in SCs during HS by disrupting mitochondrial ETC function, inferring that the release of AA is a switch-like response, and providing insight into the underlying mechanism of high temperatures causing male infertility.
Topics: Male; Sertoli Cells; Autophagy; Animals; Mitochondria; Heat-Shock Response; Arachidonic Acid; Up-Regulation; Electron Transport; Membrane Potential, Mitochondrial; Oxidative Stress; Reactive Oxygen Species
PubMed: 38797842
DOI: 10.1186/s12967-024-05182-y -
Molecular Aspects of Medicine May 2024Meiosis is a critical step for spermatogenesis and oogenesis. Meiosis commences with pre-meiotic S phase that is subsequently followed by meiotic prophase. The meiotic... (Review)
Review
Meiosis is a critical step for spermatogenesis and oogenesis. Meiosis commences with pre-meiotic S phase that is subsequently followed by meiotic prophase. The meiotic prophase is characterized by the meiosis-specific chromosomal events such as chromosome recombination and homolog synapsis. Meiosis initiator (MEIOSIN) and stimulated by retinoic acid gene 8 (STRA8) initiates meiosis by activating the meiotic genes by installing the meiotic prophase program at pre-meiotic S phase. This review highlights the mechanisms of meiotic initiation and meiotic prophase progression from the point of the gene expression program and its relevance to infertility. Furthermore, upstream pathways that regulate meiotic initiation will be discussed in the context of spermatogenic development, indicating the sexual differences in the mode of meiotic entry.
PubMed: 38797021
DOI: 10.1016/j.mam.2024.101282 -
Ecotoxicology and Environmental Safety May 2024Cranial radiotherapy is a major treatment for leukemia and brain tumors. Our previous study found abscopal effects of cranial irradiation could cause spermatogenesis...
Cranial radiotherapy is a major treatment for leukemia and brain tumors. Our previous study found abscopal effects of cranial irradiation could cause spermatogenesis disorder in mice. However, the exact mechanisms are not yet fully understood. In the study, adult male C57BL/6 mice were administrated with 20 Gy X-ray cranial irradiation (5 Gy per day for 4 days consecutively) and sacrificed at 1, 2 and 4 weeks. Tandem Mass Tag (TMT) quantitative proteomics of testis was combined with bioinformatics analysis to identify key molecules and signal pathways related to spermatogenesis at 4 weeks after cranial irradiation. GO analysis showed that spermatogenesis was closely related to oxidative stress and inflammation. Severe oxidative stress occurred in testis, serum and brain, while serious inflammation also occurred in testis and serum. Additionally, the sex hormones related to hypothalamic-pituitary-gonadal (HPG) axis were disrupted. PI3K/Akt pathway was activated in testis, which upstream molecule SCF/C-Kit was significantly elevated. Furthermore, the proliferation and differentiation ability of spermatogonial stem cells (SSCs) were altered. These findings suggest that cranial irradiation can cause spermatogenesis disorder through brain-blood-testicular cascade oxidative stress, inflammation and the secretory dysfunction of HPG axis, and SCF/C-kit drive this process through activating PI3K/Akt pathway.
PubMed: 38795418
DOI: 10.1016/j.ecoenv.2024.116504 -
Journal of Clinical Medicine May 2024Several studies have demonstrated interesting results considering the implication of three growth factors (GFs), namely nerve growth factor (NGF), erythropoietin (EPO),... (Review)
Review
Several studies have demonstrated interesting results considering the implication of three growth factors (GFs), namely nerve growth factor (NGF), erythropoietin (EPO), and the insulin-like growth factor-I (IGF-1) in the physiology of male reproductive functions. This review provides insights into the effects of NGF, EPO, and IGF-1 on the male reproductive system, emphasizing mainly their effects on sperm motility and vitality. In the male reproductive system, the expression pattern of the NGF system varies according to the species and testicular development, playing a crucial role in morphogenesis and spermatogenesis. In humans, it seems that NGF positively affects sperm motility parameters and NGF supplementation in cryopreservation media improves post-thaw sperm motility. In animals, EPO is found in various male reproductive tissues, and in humans, the protein is present in seminal plasma and testicular germ cells. EPO receptors have been discovered in the plasma membrane of human spermatozoa, suggesting potential roles in sperm motility and vitality. In humans, IGF-1 is expressed mainly in Sertoli cells and is present in seminal plasma, contributing to cell development and the maturation of spermatozoa. IGF-1 seems to modulate sperm motility, and treatment with IGF-1 has a positive effect on sperm motility and vitality. Furthermore, lower levels of NGF or IGF-1 in seminal plasma are associated with infertility. Understanding the mechanisms of actions of these GFs in the male reproductive system may improve the outcome of sperm processing techniques.
PubMed: 38792459
DOI: 10.3390/jcm13102918 -
Animals : An Open Access Journal From... May 2024We identified Wdr17 as a highly expressed gene in pachytene spermatocytes by transcriptomic analysis of mouse testis. Germ cell-deficient infertile mouse models had...
We identified Wdr17 as a highly expressed gene in pachytene spermatocytes by transcriptomic analysis of mouse testis. Germ cell-deficient infertile mouse models had significantly reduced Wdr17 expression. We performed gene interference and overexpression in the mouse spermatocyte cell line GC-2spd(ts) and investigated how Wdr17 affects spermatocyte growth and development. Our results showed that Wdr17 suppression significantly decreased cell growth rate and increased cell apoptosis in GC-2spd(ts) cells. Wdr17 suppression also arrested the cell cycle at the G1 phase. On the contrary, Wdr17 overexpression significantly promoted cell proliferation and inhibited cell apoptosis in GC-2spd(ts) cells. More cells were enriched at the S stage with a concomitant reduction of cells at the G1 stage. Wdr17 promotes mouse spermatocyte proliferation by advancing cell cycle progression and inhibiting cell apoptosis, indicating its potential role in regulating spermatogenesis in the mouse.
PubMed: 38791636
DOI: 10.3390/ani14101418