RNA-DNA differences in variant calls from cattle tissues result in erroneous eQTLs.

BACKGROUND: Association testing between molecular phenotypes and genomic variants can help to understand how genotype affects phenotype. RNA sequencing provides access to molecular phenotypes such as gene expression and alternative splicing while DNA sequencing or microarray genotyping are the prevailing options to obtain genomic variants. RESULTS: We genotype variants for 74 male Braunvieh cattle from both DNA (~ 13-fold coverage) and deep total RNA sequencing from testis, vas deferens, and epididymis tissue (~ 250 million reads per tissue). We show that RNA sequencing can be used to identify approximately 40% of variants (7-10 million) called from DNA sequencing, with over 80% precision. Within highly expressed coding regions, over 92% of expected variants were called with nearly 98% precision. Allele-specific expression and putative post-transcriptional modifications negatively impact variant genotyping accuracy from RNA sequencing and contribute to RNA-DNA differences. Variants called from RNA sequencing detect roughly 75% of eGenes identified using variants called from DNA sequencing, demonstrating a nearly 2-fold enrichment of eQTL variants. We observe a moderate-to-strong correlation in nominal association p-values (Spearman ρ2 ~ 0.6), although only 9% of eGenes have the same top associated variant. CONCLUSIONS: We find hundreds of thousands of RNA-DNA differences in variants called from RNA and DNA sequencing on the same individuals. We identify several highly significant eQTL when using RNA sequencing variant genotypes which are not found with DNA sequencing variant genotypes, suggesting that using RNA sequencing variant genotypes for association testing results in an increased number of false positives. Our findings demonstrate that caution must be exercised beyond filtering for variant quality or imputation accuracy when analysing or imputing variants called from RNA sequencing.

Evidence for NR2F2/COUP-TFII involvement in human testis development.

NR2F2 encodes COUP-TFII, an orphan nuclear receptor required for the development of the steroidogenic lineages of the murine fetal testes and ovaries. Pathogenic variants in human NR2F2 are associated with testis formation in 46,XX individuals, however, the function of COUP-TFII in the human testis is unknown. We report a de novo heterozygous variant in NR2F2 (c.737G > A, p.Arg246His) in a 46,XY under-masculinized boy with primary hypogonadism. The variant, located within the ligand-binding domain, is predicted to be highly damaging. In vitro studies indicated that the mutation does not impact the stability or subcellular localization of the protein. NR5A1, a related nuclear receptor that is a key factor in gonad formation and function, is known to physically interact with COUP-TFII to regulate gene expression. The mutant protein did not affect the physical interaction with NR5A1. However, in-vitro assays demonstrated that the mutant protein significantly loses the inhibitory effect on NR5A1-mediated activation of both the LHB and INSL3 promoters. The data support a role for COUP-TFII in human testis formation. Although mutually antagonistic sets of genes are known to regulate testis and ovarian pathways, we extend the list of genes, that together with NR5A1 and WT1, are associated with both 46,XX and 46,XY DSD.

Prenatal methamphetamine hydrochloride exposure downregulates miRNA-151-3p and CACNA1C in testis rats' offspring.

Due to the widespread use of methamphetamine (METH) among reproductive-aged women, the effects of intrauterine exposure to METH need to be investigated, as previous studies on this topic have been limited. The goal of this study is to examine the influence of two regulatory genes (miRNA-151-3p and CACNA1C) on the intrauterine life of mice exposed to METH. Pregnant mice received doses of 2 and 5 mg/kg of METH and saline from day 10 of pregnancy until the end. Their offspring were then evaluated for miRNA-151-3p and CACNA1C gene expression levels using real-time PCR. The findings indicated that exposure to METH reduced the expression levels of both miRNA-151-3p and CACNA1C genes in offspring compared to the control group (p≤0.001). In conclusion, intrauterine exposure to METH leads to a decrease in expression levels of both miRNA-151-3p and CACNA1C genes, potentially disrupting regulatory pathways involving these genes and having an impact on male reproductive health.

Schisandrin B alleviates testicular inflammation and Sertoli cell apoptosis via AR-JNK pathway.

Bacterial testicular inflammation is one of the important causes of male infertility. Using plant-derived compounds to overcome the side effects of antibiotics is an alternative treatment strategy for many diseases. Schizandrin B (SchB) is a bioactive compound of herbal medicine Schisandra chinensis which has multiple pharmacological effects. However its effect and the mechanism against testicular inflammation are unknown. Here we tackled these questions using models of lipopolysaccharide (LPS)-induced mice and -Sertoli cells (SCs). Histologically, SchB ameliorated the LPS-induced damages of the seminiferous epithelium and blood-testicular barrier, and reduced the production of pro-inflammatory mediators in mouse testes. Furthermore, SchB decreased the levels of pro-inflammatory mediators and inhibited the nuclear factor kB (NF-κB) and MAPK (especially JNK) signaling pathway phosphorylation in LPS-induced mSCs. The bioinformatics analysis based on receptor prediction and the molecular docking was further conducted. We targeted androgen receptor (AR) and illustrated that AR might bind with SchB in its function. Further experiments indicate that the AR expression was upregulated by LPS stimulation, while SchB treatment reversed this phenomenon; similarly, the expression of the JNK-related proteins and apoptotic-related protein were also reversed after AR activator treatment. Together, SchB mitigates LPS-induced inflammation and apoptosis by inhibiting the AR-JNK pathway.

The protection afforded by kefir against cyclophosphamide induced testicular toxicity in rats by oxidant antioxidant and histopathological evaluations.

Cyclophosphamide (CTX) is the most commonly used effective alkylating drug in cancer treatment, but its use is restricted because its toxic side effect causes testicular toxicity. CTX disrupts the tissue redox and antioxidant balance and the resulting tissue damage causes oxidative stress. In our study based on this problem, kefir against CTX-induced oxidative stress and testicular toxicity were investigated. Rats were divided into 6 groups: control, 150 mg/kg CTX, 5 and 10 mg/kg kefir, 5 and 10 mg/kg kefir + 150 CTX. While the fermented kefirs were mixed and given to the rats for 12 days, CTX was given as a single dose on the 12th day of the experiment. Testis was scored according to spermatid density, giant cell formation, cells shed into tubules, maturation disorder, and atrophy. According to our biochemical findings, the high levels of total oxidant status (TOS), and the low levels of total antioxidant status (TAS) in the CTX group, which are oxidative stress markers, indicate the toxic effect of CTX, while the decrease in TOS levels and the increase in TAS levels in the kefir groups indicate the protective effect of kefir. In the CTX-administered group, tubules with impaired maturation and no spermatids were observed in the transverse section of the testicle, while in the kefir groups, the presence of near-normal tubule structures and tubule lumens despite CTX showed the protective effect of kefir. In our study, it was observed that kefir had a protective and curative effect on CTX-induced toxicity and oxidative stress and could be a strong protector.

Oat Beta-Glucan Dietary Intervention on Antioxidant Defense Parameters, Inflammatory Response and Angiotensin Signaling in the Testes of Rats with TNBS-Induced Colitis.

Male infertility represents a significant public health concern. There is a negative impact of inflammatory bowel diseases (IBDs) on the male reproductive system. The aim of this study was to investigate whether oat beta-glucan (OBG) with different molar mass can modulate parameters of antioxidant defense and inflammatory response in the testes of adult Sprague-Dawley rats with TNBS-induced colitis and whether the OBG intervention can modulate the inflammatory response in association with the RAS system. Results: higher testicular superoxide dismutase (SOD), glutathione reductase (GR) activities and glutathione (GSH) concentration, and lower testosterone (T) level and glutathione peroxidase (GPx) activity, were observed in rats with colitis than in healthy control ones. TNBS-induced colitis resulted in decreased the angiotensin 1-7 (ANG 1-7) level in the testes of rats fed with low-molar mass OBG compared to control animals. Conclusions: although colitis induced moderate pro-oxidant changes in the gonads, it seems plausible that dietary intervention with different fractions of oat beta-glucans mass may support the maintenance of reproductive homeostasis via the stimulation of the local antioxidant defense system.

MALDI Imaging Mass Spectrometry Reveals Lipid Alterations in Physiological and Sertoli Cell-Only Syndrome Human Testicular Tissue Sections.

Azoospermia, the absence of sperm cells in semen, affects around 15% of infertile males. Sertoli cell-only syndrome (SCOS) is the most common pathological lesion in the background of non-obstructive azoospermia and is characterised by the complete absence of germinal epithelium, with Sertoli cells exclusively present in the seminiferous tubules. Studies have shown a correlation between successful spermatogenesis and male fertility with lipid composition of spermatozoa, semen, seminal plasma or testis. The aim of this research was to discover the correlation between the Johnsen scoring system and phospholipid expressions in testicular cryosections of SCOS patients. MALDI imaging mass spectrometry is used to determine spatial distributions of molecular species, such as phospholipids. Phosphatidylcholines (PCs), phosphatidylethanolamines (PEs) and sphingomyelins (SMs) are the most abundant phospholipids in mammalian cells and testis. SMs, the structural components of plasma membranes, are crucial for spermatogenesis and sperm function. Plasmalogens, are unique PCs in testis with strong antioxidative properties. This study, using imaging mass spectrometry, demonstrates the local distribution of phospholipids, particularly SMs, PCs, plasmalogens and PEs in human testicular samples with SCOS for the first time. This study found a strong relationship between the Johnsen scoring system and phospholipid expression levels in human testicular tissues. Future findings could enable routine diagnostic techniques during microTESE procedures for successful sperm extraction.

Quantitative Proteomic Analysis Reveals Key Proteins Involved in Testicular Development of Yaks.

Male reproductive health is largely determined already in the early development of the testis. Although much work has been carried out to study the mechanisms of testicular development and spermatogenesis, there was previously no information on the differences in the protein composition of yak testicles during early development. In this study, the protein profiles in the testicles of 6- (M6), 18- (M18), and 30-month-old (M30) yaks were comparatively analyzed using TMT proteomics. A total of 5521 proteins were identified, with 13, 1295, and 1397 differentially expressed proteins (DEPs) in 30- vs. 18-, 18- vs. 6-, and 30- vs. 6-month-old testes, respectively. Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that DEPs were mainly involved in signaling pathways related to testicular development and spermatogenesis, including the MAPK, PI3K-Akt, Wnt, mTOR, TGF-ß, and AMPK signaling pathways. Furthermore, we also identified eight potential proteins (TEX101, PDCL2, SYCP2, SYCP3, COL1A1, COL1A2, ADAM10, and ATF1) that may be related to the testicular development and spermatogenesis of yaks. This study may provide new insights into the molecular mechanisms of the testicular development and spermatogenesis of yaks.

Protective effect of Cordycepin on blood-testis barrier against pre-puberty polystyrene nanoplastics exposure in male rats.

Plastic pollution is an emerging environmental issue, with microplastics and nanoplastics raising health concerns due to bioaccumulation. This work explored the impact of polystyrene nanoparticle (PS-NPs) exposure during prepuberty on male reproductive function post maturation in rats. Rats were gavaged with PS-NPs (80 nm) at 0, 3, 6, 12 mg/kg/day from postnatal day 21 to 95. PS-NPs accumulated in the testes and reduced sperm quality, serum reproductive hormones, and testicular coefficients. HE staining showed impaired spermatogenesis. PS-NPs disrupted the blood-testis barrier (BTB) by decreasing junction proteins, inducing inflammation and apoptosis. Transcriptomics identified differentially expressed genes related to metabolism, lysosome, apoptosis, and TLR4 signaling. Molecular docking revealed Cordycepin could compete with polystyrene for binding to TLR4. Cordycepin alleviated oxidative stress and improved barrier function in PS-NPs treated Sertoli cells. In conclusion, prepubertal PS-NPs exposure induces long-term reproductive toxicity in male rats, likely by disrupting spermatogenesis through oxidative stress and BTB damage. Cordycepin could potentially antagonize this effect by targeting TLR4 and warrants further study as a protective agent. This study elucidates the mechanisms underlying reproductive toxicity of PS-NPs and explores therapeutic strategies.

The Novel-m0230-3p miRNA Modulates the CSF1/CSF1R/Ras Pathway to Regulate the Cell Tight Junctions and Blood-Testis Barrier in Yak.

The yak (Bos grunniens) is a valuable livestock animal endemic to the Qinghai-Tibet Plateau in China with low reproductive rates. Cryptorchidism is one of the primary causes of infertility in male yaks. Compared with normal testes, the tight junctions (TJs) of Sertoli cells (SCs) and the integrity of the blood-testis barrier (BTB) in cryptorchidism are both disrupted. MicroRNAs are hairpin-derived RNAs of about 19-25 nucleotides in length and are involved in a variety of biological processes. Numerous studies have shown the involvement of microRNAs in the reproductive physiology of yak. In this study, we executed RNA sequencing (RNA-seq) to describe the expression profiles of mRNAs and microRNAs in yaks with normal testes and cryptorchidism to identify differentially expressed genes. GO and KEGG analyses were used to identify the biological processes and signaling pathways which the target genes of the differentially expressed microRNAs primarily engaged. It was found that novel-m0230-3p is an important miRNA that significantly differentiates between cryptorchidism and normal testes, and it is down-regulated in cryptorchidism with p < 0.05. Novel-m0230-3p and its target gene CSF1 both significantly contribute to the regulation of cell adhesion and tight junctions. The binding sites of novel-m0230-3p with CSF1 were validated by a dual luciferase reporter system. Then, mimics and inhibitors of novel-m0230-3p were transfected in vitro into SCs, respectively. A further analysis using qRT-PCR, immunofluorescence (IF), and Western blotting confirmed that the expression of cell adhesion and tight-junction-related proteins Occludin and ZO-1 both showed changes. Specifically, both the mRNA and protein expression levels of Occludin and ZO-1 in SCs decreased after transfection with the novel-m0230-3p mimics, while they increased after transfection with the inhibitors, with p < 0.05. These were achieved via the CSF1/CSF1R/Ras signaling pathway. In summary, our findings indicate a negative miRNA-mRNA regulatory network involving the CSF1/CSF1R/Ras signaling pathway in yak SCs. These results provide new insights into the molecular mechanisms of CSF1 and suggest that novel-m0230-3p and its target protein CSF1 could be used as potential therapeutic targets for yak cryptorchidism.

Isolation of Homogeneous Sub-populations of Spermatocytes from Mouse Testis.

Mammalian meiosis is a highly specialized cell division process, resulting in the production of genetically unique haploid cells. However, the molecular mechanisms governing meiosis remain largely unknown, primarily due to the difficulty in isolating pure sub-populations of spermatocytes. Definitive molecular, biochemical, and functional investigations of the meiosis process require the isolation of these individual homogeneous sub-populations of spermatocytes. Here, we present an approach that enables the purification of homogeneous spermatocytes from mouse testis at desired sub-stages. This approach consists of two strategic steps. The first is to synchronize spermatogenesis, aiming to minimize the diversity and complexity of testicular germ cells. The second involves utilizing mouse models with germ cell-specific fluorescent markers to differentiate the desired subtype from other cells in the testis. By employing fluorescence-activated cell sorting (FACS), this approach yields highly pure populations of spermatocytes at each sub-stage. When combined with other massively parallel sequencing techniques and in vitro cell culture methods, this approach will enhance our comprehension of the molecular mechanisms underlying mammalian meiosis and promote in vitro gametogenesis.

Inherited defects of piRNA biogenesis cause transposon de-repression, impaired spermatogenesis, and human male infertility.

piRNAs are crucial for transposon silencing, germ cell maturation, and fertility in male mice. Here, we report on the genetic landscape of piRNA dysfunction in humans and present 39 infertile men carrying biallelic variants in 14 different piRNA pathway genes, including PIWIL1, GTSF1, GPAT2, MAEL, TDRD1, and DDX4. In some affected men, the testicular phenotypes differ from those of the respective knockout mice and range from complete germ cell loss to the production of a few morphologically abnormal sperm. A reduced number of pachytene piRNAs was detected in the testicular tissue of variant carriers, demonstrating impaired piRNA biogenesis. Furthermore, LINE1 expression in spermatogonia links impaired piRNA biogenesis to transposon de-silencing and serves to classify variants as functionally relevant. These results establish the disrupted piRNA pathway as a major cause of human spermatogenic failure and provide insights into transposon silencing in human male germ cells.

Echis ocellatus venom-induced sperm functional deficits, pro-apoptotic and inflammatory activities in male reproductive organs in rats: antagonistic role of kaempferol.

BACKGROUND: Echis ocellatus envenoming is potentially toxic initiating clinical damages on male reproductive system. Kaempferol is a therapeutic agent with neutralizing potentials on snake venom toxins. This study investigated the antagonistic effect of kaempferol on E. ocellatus venom (EoV)-induced reproductive toxicities. METHODS: Fifty adult male rats were sorted at random into five groups of ten rats for this study. The control rats were allotted to group 1, while rats in groups 2-5 were injected with 0.22 mg/kg bw (LD50) of EoV intraperitoneally. Rats in group 2 were not treated while groups 3-5 rats were treated with serum antivenom (0.2 ml), and 4 and 8 mg/kg bw of kaempferol post envenoming, respectively. RESULTS: EoV actuated reproductive toxicity, significantly decreased sperm parameters, and enhanced inflammatory, oxidative stress, and apoptotic biomarkers in reproductive organs of untreated envenomed rats. However, treatment with kaempferol alleviated the venom-induced reproductive disorders with a dose dependent effect. Kaempferol significantly increased the testicular weight, organo-somatic index, sperm parameters, and normalized the levels of serum luteinizing hormone, testosterone, and follicle stimulating hormone. Kaempferol ameliorated testicular and epididymal oxidative stress as evidenced by significant decrease in malondialdehyde (MDA) levels, enhancement of reduced glutathione (GSH) levels, superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities. The inflammatory biomarkers; nitric oxide (NO) levels and myeloperoxidase activity (MPO), and apoptotic biomarkers; caspase 3 and caspase 9 activities were substantially suppressed in the testis and epididymis of envenomed rats treated with kaempferol. CONCLUSION: Results revealed kaempferol as a potential remedial agent against reproductive toxicity that could manifest post-viper envenoming.

[The Roles of N6-Methyladenosine Modification and Its Regulators in Male Reproduction]. / N6-ç”²åŸºè ºå˜Œå‘¤ä¿®é¥°åŠå ¶è°ƒæŽ§å› å­åœ¨ç”·æ€§ç”Ÿæ®–ä¸­çš„ä½œç”¨.

Infertility affects an estimated 10 to 15 percent of couples worldwide, with approximately half of the cases attributed to male-related issues. Most men diagnosed with infertility exhibit symptoms such as oligospermia, asthenospermia, azoospermia, and compromised sperm quality. Spermatogenesis is a complex and tightly coordinated process of germ cell differentiation, precisely regulated at transcriptional, posttranscriptional, and translational levels to ensure stage-specific gene expression during the development of spermatogenic cells and normal spermiogenesis. N6-methyladenosine (m6A) stands out as the most prevalent modification on eukaryotic mRNA, playing pivotal roles in various biological processes, including mRNA splicing, transportation, and translation. RNA methylation modification is a dynamic and reversible process primarily mediated by "writers", removed by "erasers", and recognized by "readers". In mammals, the aberrant methylation modification of m6A on mRNA is associated with a variety of diseases, including male infertility. However, the precise involvement of disrupted m6A modification in the pathogenesis of human male infertility remains unresolved. Intriguingly, a significant correlation has been found between the expression levels of m6A regulators in the testis and the severity of sperm concentration, motility, and morphology. Aberrant expression patterns of m6A regulatory proteins have been detected in anomalous human semen samples, including those of oligospermia, asthenozoospermia, and azoospermia. Furthermore, the examination of both sperm samples and testicular tissues revealed abnormal mRNA m6A modification, leading to reduced sperm motility and concentration in infertile men. Consequently, it is hypothesized that dysregulation of m6A modification might serve as an integral link in the mechanism of male infertility. This paper presents a comprehensive review of the recent discoveries regarding the spatial and temporal expression dynamics of m6A regulators in testicular tissues and the correlation between deregulated m6A regulators and human male infertility. Previous studies predominantly utilized constitutive or conditional knockout animal models for testicular phenotypic investigations. However, gene suppression in additional tissues could potentially influence the testis in constitutive knockout models. Furthermore, considering the compromised spermatogenesis observed in constitutive animals, distinguishing between the indirect effects of gene depletion on testicular development and its direct impact on the spermatogenic process is challenging, due to their intricate relationship. Such confounding factors might compromise the validity of the findings. To address this challenge, an inducible and conditional gene knockout model may serve as a superior approach. To date, nearly all reported studies have concentrated solely on the level changes of m6A and its regulators in germs cells, while the understanding of the function of m6A modification in testicular somatic cells remains limited. Testicular somatic cells, including peritubular myoid cells, Sertoli cells, and Leydig cells, play indispensable roles during spermatogenesis. Hence, comprehensive exploration of m6A modification within these cells as an additional crucial regulatory mechanism is warranted. In addition, exploration into the presence of unique methylation mechanisms or m6A regulatory factors within the testes is warranted. To elucidate the role of m6A modification in germ cells and testicular somatic cells, detailed experimental strategies need to be implemented. Among them, manipulation of the levels of key enzymes involved in m6A methylation and demethylation might be the most effective approach. Moreover, comprehensive analysis of the gene expression profiles involved in various signaling pathways, such as Wnt/ß-catenin, Ras/MAPK, and Hippo, in m6A-modified germ cells and testicular somatic cells can provide more insight into its regulatory role in the spermatogenesis process. Further research in this area could provide valuable insights for developing innovative strategies to treat male infertility. Finally, considering the mitigation impact of m6A imbalance regulation on disease, investigation concerning whether restoring the equilibrium of m6A modification regulation can restore normal spermatogenesis function is essential, potentially elucidating the pivotal clinical significance of m6A modulation in male infertility.

Molecular insights into Sertoli cell function: how do metabolic disorders in childhood and adolescence affect spermatogonial fate?

Male infertility is a major public health concern globally with unknown etiology in approximately half of cases. The decline in total sperm count over the past four decades and the parallel increase in childhood obesity may suggest an association between these two conditions. Here, we review the molecular mechanisms through which obesity during childhood and adolescence may impair future testicular function. Several mechanisms occurring in obesity can interfere with the delicate metabolic processes taking place at the testicular level during childhood and adolescence, providing the molecular substrate to hypothesize a causal relationship between childhood obesity and the risk of low sperm counts in adulthood.

ZnO NPs induce miR-342-5p mediated ferroptosis of spermatocytes through the NF-κB pathway in mice.

BACKGROUND: Zinc oxide nanoparticle (ZnO NP) is one of the metal nanomaterials with extensive use in many fields such as feed additive and textile, which is an emerging threat to human health due to widely distributed in the environment. Thus, there is an urgent need to understand the toxic effects associated with ZnO NPs. Although previous studies have found accumulation of ZnO NPs in testis, the molecular mechanism of ZnO NPs dominated a decline in male fertility have not been elucidated. RESULTS: We reported that ZnO NPs exposure caused testicular dysfunction and identified spermatocytes as the primary damaged site induced by ZnO NPs. ZnO NPs led to the dysfunction of spermatocytes, including impaired cell proliferation and mitochondrial damage. In addition, we found that ZnO NPs induced ferroptosis of spermatocytes through the increase of intracellular chelatable iron content and lipid peroxidation level. Moreover, the transcriptome analysis of testis indicated that ZnO NPs weakened the expression of miR-342-5p, which can target Erc1 to block the NF-κB pathway. Eventually, ferroptosis of spermatocytes was ameliorated by suppressing the expression of Erc1. CONCLUSIONS: The present study reveals a novel mechanism in that miR-342-5p targeted Erc1 to activate NF-κB signaling pathway is required for ZnO NPs-induced ferroptosis, and provide potential targets for further research on the prevention and treatment of male reproductive disorders related to ZnO NPs.

Biogenic amines in the testis: sources, receptors and actions.

Biogenic amines are signaling molecules with multiple roles in the central nervous system and in peripheral organs, including the gonads. A series of studies indicated that these molecules, their biosynthetic enzymes and their receptors are present in the testis and that they are involved in the regulation of male reproductive physiology and/or pathology. This mini-review aims to summarize the current knowledge in this field and to pinpoint existing research gaps. We suggest that the widespread clinical use of pharmacological agonists/antagonists of these signaling molecules, calls for new investigations in this area. They are necessary to evaluate the relevance of biogenic amines for human male fertility and infertility, as well as the potential value of at least one of them as an anti-aging compound in the testis.

Motor proteins, spermatogenesis and testis function.

The role of motor proteins in supporting intracellular transports of vesicles and organelles in mammalian cells has been known for decades. On the other hand, the function of motor proteins that support spermatogenesis is also well established since the deletion of motor protein genes leads to subfertility and/or infertility. Furthermore, mutations and genetic variations of motor protein genes affect fertility in men, but also a wide range of developmental defects in humans including multiple organs besides the testis. In this review, we seek to provide a summary of microtubule and actin-dependent motor proteins based on earlier and recent findings in the field. Since these two cytoskeletons are polarized structures, different motor proteins are being used to transport cargoes to different ends of these cytoskeletons. However, their involvement in germ cell transport across the blood-testis barrier (BTB) and the epithelium of the seminiferous tubules remains relatively unknown. It is based on recent findings in the field, we have provided a hypothetical model by which motor proteins are being used to support germ cell transport across the BTB and the seminiferous epithelium during the epithelial cycle of spermatogenesis. In our discussion, we have highlighted the areas of research that deserve attention to bridge the gap of research in relating the function of motor proteins to spermatogenesis.

Characterisation of germline progenitor cells in the testes of phylostomid bats: Artibeus jamaicensis and Sturnira lilium.

Context A population of sperm progenitor cells, known as Asingle spermatogonia, has been described in mammalian testes. During division cycles in spermatogenesis, some cells will form part of the Asingle spermatogonia group, while others form primary spermatocytes. Thus, during spermatogenesis, spermatogonia are the progenitor cells of spermatozoa. Aims In this study, we characterise the spermatogonial stem cells (SSCs) in the testicles of Artibeus jamaicensis and Sturnira lilium bats. The knowledge generated from this will contribute to the understanding of the biology of germ cells and the mechanisms of spermatogenesis in mammals, generating information on wildlife species that are important for biodiversity. Methods Testes were analysed by light and electron microscopy. Likewise, the expression of specific factors of stem cells (Oct4 and C-kit), germ cells (Vasa), cell proliferation (pH3 and SCP1) and testicular somatic cells (MIS, 3ßHSD and Sox9) was characterised by immunofluorescence and western blot. Key results The histological analysis enabled the location of type Asingle, Apaired and Aaligned spermatogonia in the periphery of the seminiferous tubules adjacent to Sertoli cells. The expression of genes of stem and germ cells made it possible to corroborate the distribution of the SSCs. Conclusions Results indicate that type Asingle spermatogonia were not randomly distributed, since proliferative activity was detected in groups of cells adjacent to the seminiferous tubules membrane, suggesting the localisation of spermatogonial niches in a specific region of testes. Implications This study provides evidence for the existence of SSCs in the testis of chiropterans that contribute to the renewal of germline progenitor cells to maintain the reproduction of the organisms.

Ursolic acid attenuates oligospermia in busulfan-induced mice by promoting motor proteins.

Background: Oligospermia is one of the most common reasons for male infertility which is troubling numerous couples of child-bearing age. This investigation scrutinizes the implications and mechanistic underpinnings of ursolic acid's effect on busulfan-induced oligospermia in mouse models. Methods: A singular intraperitoneal injection of busulfan at a dosage of 30 mg/kg induced oligospermia. Two weeks subsequent to this induction, mice were subjected to various dosages of ursolic acid (10, 30, and 50 mg/kg body weight, respectively) on a daily basis for four consecutive weeks. Following this treatment period, a meticulous analysis of epididymal sperm parameters, encompassing concentration and motility, was conducted using a computer-assisted sperm analysis system. The histopathology of the mice testes was performed utilizing hematoxylin and eosin staining, and the cytoskeleton regeneration of the testicular tissues was analyzed via immunofluorescent staining. Serum hormone levels, including testosterone, luteinizing hormone, and follicle-stimulating hormone, as well as reactive oxygen species levels (inclusive of reactive oxygen species and malondialdehyde), were gauged employing specific enzyme-linked immunosorbent assay kits. Differentially expressed genes of testicular mRNA between the oligospermia-induced group and the various ursolic acid treatment groups were identified through RNA sequencing analysis. Results: The results revealed that a dosage of 50 mg/kg ursolic acid treatment could increase the concentration of epididymal sperm in oligospermia mice, promote the recovery of testicular morphology, regulate hormone levels and ameliorate oxidative damage. The mechanism research results indicated that ursolic acid increased the expression level of genes related to motor proteins in oligospermia mice.