Search Results (170)

This study aimed to describe the endocrine, cellular, and transcriptomic changes associated with mild heat stress responses in Wugu-Hu and Hu rams. Testicular samples from rams exposed to 3 days of scrotal insulation, resulting in an approximate 3 °C increase in scrotal temperature, and corresponding controls were analyzed for endocrine activity, seminiferous tubule morphology, germ cell composition, and transcriptomic profiles. There were no significant changes in testosterone, follicle-stimulating hormone, or luteinizing hormone after 3 days of mild heat exposure in either breed. Wugu-Hu rams showed greater disorganization of seminiferous tubules. Apoptotic events occurred mainly from spermatocytes to spermatids and were accompanied by a greater decline in spermatids in Wugu-Hu rams. Comparative transcriptomic analysis between Wugu-Hu and Hu rams identified 854 differentially expressed genes, mainly enriched in immune response function. We conclude that scrotal heat stress does not disrupt endocrine balance at the level applied in this study, but it induces breed-dependent morphological and testicular cellular responses. The differences in the immune response of Hu and Wugu-Hu rams may contribute to their distinct levels of spermatocytes and spermatids’ response to elevated temperatures. Full article

Background/Objectives: Round spermatid injection (ROSI) is considered an experimental “last resort” option for couples with severe male factor infertility when mature spermatozoa cannot be obtained. We aimed to identify which stage of the clinical chain most strongly constrains overall success in routine practice and to describe the observed safety signal. Methods: We conducted a retrospective single-center cohort study of 221 consecutive ROSI-evaluated cycles (2021–2024). Outcomes were analyzed using a chain-of-outcome framework with explicit denominators: cycle-level feasibility (≥1 injected oocyte), two pronuclei (2PN) formation per injected oocyte, blastocyst development per 2PN, transfer per blastocyst cycle, and clinical pregnancy per transfer and per initiated cycle. Exact (Clopper–Pearson) 95% confidence intervals (CIs) were reported. Results: ROSI feasibility was observed in 5 of 221 initiated cycles (2.3%; exact 95% CI 0.7–5.2). Among the five transfer procedures performed after successful progression through upstream stages, clinical pregnancy occurred in four (80.0%; exact 95% CI 28.4–99.5). At the initiated-cycle level, overall clinical pregnancy was 4 of 221 cycles (1.8%; exact 95% CI 0.5–4.6). Conclusions: The overall effectiveness of ROSI remained low at the initiated-cycle level because very few cycles reached procedural feasibility and early attrition remained substantial. Conditional downstream outcomes may appear favorable only among the rare cycles reaching fertilization and transfer, while safety inference remains highly imprecise due to small denominators. Because only five cycles reached feasibility, all downstream conditional estimates remained highly unstable and sensitive to single-case variation. Full article

In livestock farming, the reproductive function and breeding performance of Tan sheep are crucial for enhancing farming efficiency. Despite advances in research on sheep germ cells, studies on the identification of markers for spermatogonia, spermatocytes, and spermatozoa in Tan sheep remain limited and inadequate. In this study, Tan sheep were used as research subjects to investigate the morphological characteristics of testicular tissues, the developmental status of germ cells, and potential novel markers for spermatogonia, spermatocytes, and spermatozoa across different ages (0 days, 60 days, 180 days, and 365 days). Homology of the SMC3, G3BP1, and AKAP4 genes was analyzed via NCBI alignment. The localization and expression characteristics of these genes in the testis tissues of Tan sheep were investigated using HE staining, qPCR, and immunofluorescence double staining. The results showed that from 0 to 365 days of age, with increasing age, spermatogonia, spermatocytes, and spermatids exhibited an orderly distribution, and mature spermatozoa appeared in the tubular lumen, marking the initial establishment of the spermatogenic process. The homology of SMC3, G3BP1, and AKAP4 was 90%, 85%, and 81%. The mRNA levels of SMC3 and G3BP1 in the testes of 60-day-old Tan sheep were significantly increased, while AKAP4 expression showed a gradual increase with advancing age. SMC3 was co-localized with PLZF in undifferentiated spermatogonia, G3BP1 was co-expressed with SYCP2 in spermatocytes, and AKAP4 was co-expressed with PNA in spermatozoa. The findings of this study provide further supportive evidence for novel markers of spermatogonia, spermatocytes, and spermatozoa in Tan sheep. Full article

Spermiogenesis requires extensive molecular and structural remodeling to produce motile sperm. Mutations in the testis-specific RNA methyltransferase NSUN7 are associated with defective fibrous sheath, impaired sperm motility, and male infertility. However, the underlying molecular mechanisms remain poorly understood. Here, we performed proteomic profiling of sorted, elongated, and round spermatids, as well as mature spermatozoa from Nsun7 knockout mice. We showed that NSUN7 is present at all stages of spermiogenesis and is most abundant in round spermatids, which corresponds to the formation of the flagellum and fibrous sheath assembly. Loss of NSUN7 altered the abundance of proteins essential for dynein arm assembly (PIH1D3, CCDC103, CCDC40), intraflagellar transport (IFT122), and fibrous sheath organization (AKAP3, AKAP4, ROPN1L). We also showed that the previously detected impaired retention of cytoplasm in elongated spermatids may be caused by plectin accumulation. Interestingly, no statistically significant changes were found in mature sperm proteomes upon Nsun7 inactivation. Our findings support a model in which NSUN7 primarily stabilizes protein complexes and coordinates flagellar assembly. This indicates that NSUN7 is a critical regulator of spermiogenesis, and its malfunction is a contributing factor to male infertility. Full article

Background: Normal spermatogenesis in Mongolian horses depends on the mitotic division of spermatogonia, two successive meiotic divisions, and the morphological transformation of spermatids into mature spermatozoa. The MEI1 gene is involved in the meiosis cycle and is required for normal chromosome association during meiosis. Previous studies have shown that alternative splicing of MEI1 may promote spermatogenesis in Mongolian horses. In this paper, the regulatory effects of different MEI1 alternative splicing events on Mongolian horse spermatogenesis are investigated. Results: In this study, two overexpressed lentiviral vectors with mutually exclusive exon (MXE) and skipped exon (SE) events of MEI1 were constructed and successfully used to infect Sertoli cells. After 72 h of viral infection, the expression of MEI1 was higher in the SE event than in the MXE event (p < 0.001), as shown by fluorescence quantification; transcriptomics and metabolomics were then used to screen and annotate the differential genes and metabolites, and 193 differentially expressed genes (comprising 109 genes, such as MEI1, and 84 genes with upregulated and downregulated expression, respectively) and 11,360 differentially expressed metabolites (comprising 7494 and 3866 metabolites with upregulated and downregulated expression, respectively) were screened. Differential genes and metabolites were mainly enriched in several metabolic pathways related to spermatogenesis. Differential genes such as IL31RA, ATP2B3, and CASQ2 were highly expressed in SE events, while IL11, PRLR, and CCR7 were highly expressed in MXE events. Metabolites such as folic acid and spermine were highly expressed during SE events, while citric acid and glutathione were highly expressed during MXE events. This suggests that both MXE and SE events of the MEI1 gene can promote the activity of the spermatogenesis signaling pathway. Conclusions: The MXE and SE splicing events of the MEI1 gene may influence spermatogenesis by regulating the expression of spermatogenesis-related genes and metabolites. These findings provide a theoretical foundation for further investigations into the regulatory mechanisms of different alternative splicing events in Mongolian horse spermatogenesis. Full article

Spermatogenesis in passerine birds remains poorly characterized. Previous studies focused on the steps of spermiogenesis, while a detailed staging of the seminiferous epithelium cycle is still lacking for this order. In this study, we provide the first comprehensive histological characterization of spermatogenesis in a model passerine species, the zebra finch. We defined ten distinct steps of spermiogenesis based on acrosomal and nuclear morphology of spermatids in Periodic acid–Schiff-stained histological sections. Using this classification, we further defined seven stages of the seminiferous epithelium, encompassing cytological features associated with the programmed DNA elimination, which is unique to passerines. Our analysis revealed that seminiferous tubules of the zebra finch exhibit a mosaic organization typical of all birds examined so far. However, in this species, most stages were characterized by the presence of spermatids at three developmental steps, in contrast to the one to two steps typical of non-passerine birds. To facilitate future comparative studies, we developed a flowchart for determining the stages of the seminiferous epithelium cycle. This work establishes an essential histological framework for future research in reproductive biology of the zebra finch and other passerine species. Full article

Gene expression plays a fundamental role in defining the characteristics of living organisms. To deepen our understanding of tissue-specific gene expression, we analyzed transcript variant enrichment across different tissues in human and Drosophila melanogaster. Datasets are widely accessible for both of these organisms. Given the substantial volume of available information, we have focused our interest on three fundamentally distinct tissues: the brain, where both neuronal and glial cells exhibit a relatively high cellular surface area, thus requiring a large amount of lipids; the adipose tissue, which is well-known for lipid storage; and the testis, which contains a massive number of developing spermatids with high membrane requirement. These three organs have fundamental differences in their structure and function yet share some common features; they all have lipid-rich cells and have special metabolic pathways. Most studies focus on gene expression, and transcript level analyses are less common; therefore, we aimed to characterize the transcript profiles of these tissues and examine evolutionarily conserved pathways between humans and Drosophila. Additionally, we analyzed the flanking sequences of transcriptional start sites of tissue-enriched transcripts. Our findings suggest that Drosophila tissues exhibit more distinct regulation of gene expression in individual tissues (weaker correlation in expression and variable nucleotide content in core promoter), whereas human gene expression is more generalized, likely relying more heavily on distal regulatory elements for tissue-specific expression. Through network analysis, summarizing tissue specificity, physical interactions, and orthologue data, we identified shared central pathways among these tissues. A relatively large network was observable in the testis, where the ubiquitin proteasome system, various kinases and transcription factors showed central position in both organisms. Additionally, we highlighted the evolutionary potential of highly enriched testis-specific transcripts. This work provides valuable insights into the mechanisms underlying tissue-specific gene expression and evolutionary conservation. Full article

Sulfoxaflor, an insecticide, acts on nicotinic acetylcholine receptors. It has a functional group similar to that of neonicotinoid insecticides, which are testicular toxicants. Recently, the adverse effects of sulfoxaflor on the testes have been reported in rats. This study aimed to address the lack of reports on sulfoxaflor administration in mice and its effects on the testes. ICR mice (3- and 10-week-old) were treated ad libitum with two different concentrations (10 and 100 mg/kg) of sulfoxaflor for 4 and 8 weeks. Histological analysis and real-time reverse transcription polymerase chain reaction were performed. Testis weights relative to body weights in the sulfoxaflor groups showed no significant difference compared to the control group. Testicular tissue in the sulfoxaflor groups was unchanged compared to that in the control group. The sulfoxaflor-treated group showed no significant differences in the mRNA expression of luteinizing hormone and follicle-stimulating hormone in the pituitary gland compared to the control group. Furthermore, no significant differences were noted in the mRNA expression levels of various gene markers in the testes between the sulfoxaflor-treated and control groups. These markers include those related to Leydig cells, testosterone synthesis, Sertoli cells, proliferating cells, meiotic cells, pachytene spermatocytes, round spermatids, apoptotic cells, antioxidant enzymes, oxidative stress factors, and mitochondrial function. In contrast to findings in rats, which showed testicular toxicity, sulfoxaflor administration at low concentrations did not adversely affect intratesticular cells in either mature or immature mice at the doses and time points examined. In the future, we would like to conduct research on high concentrations of sulfoxaflor by changing the administration method. Full article

Background: Spermatogenesis depends on precise cytoskeletal regulation, particularly the microtubule system; however, the mechanisms governing tubulin homeostasis during meiosis are poorly defined. While the E3 ubiquitin ligase Hyd (Hyperplastic discs), the Drosophila homolog of UBR5 (Ubiquitin Protein Ligase E3 Component N-Recognin 5), plays roles in diverse cellular processes, its precise role in male meiosis is unknown. This study aims to define the function and expression dynamics of Hyd during Drosophila spermatogenesis and elucidate whether it acts independently of its canonical ligase activity. Methods: Using Drosophila genetics, immunofluorescence, CRISPR/Cas9-mediated tagging, and mosaic clonal analysis, we characterized Hyd expression and function in the testis. Hyd knockdown and rescue experiments were performed with wild-type and catalytically inactive transgenes. β2-tubulin expression and microtubule organization were assessed in hyd mutant clones. Results: Hyd exhibits a dynamic, stage-specific expression pattern, localizing to nuclear and meiotic structures. Hyd loss led to meiotic arrest, disrupted spindle formation, aberrant centrosome behavior, and failure of spermatid elongation. Genetic rescue demonstrated that both wild-type and catalytically inactive Hyd partially restored spermatid elongation, indicating a catalysis-independent role. Furthermore, Hyd deficiency resulted in β2-tubulin overexpression, disrupted microtubule organization, and abnormal spermatocyte morphology. Conclusions: Hyd ensures meiotic fidelity in Drosophila by fine-tuning β2-tubulin expression independently of its E3 ubiquitin ligase activity. These findings reveal a non-proteolytic function for UBR5/Hyd in cytoskeletal regulation during male gametogenesis, providing new insights into tubulin homeostasis in meiosis. Full article

Bats have unique reproductive strategies that are closely related to testicular metabolic adaptations, such as prolonged sperm storage. This study examined the expression of glucose transporter 5 (GLUT-5), a fructose-specific member of the facilitative glucose transporter family, in the testes of roundleaf bats (Hipposideros spp.) collected from various locations in Thailand during their active reproductive season (July to September) and explored its association with biometric traits. To assess GLUT-5’s localization and expression levels, testicular tissues from 50 adult males representing Hipposideros larvatus, Hipposideros armiger, and Hipposideros lekaguli species were analyzed using immunohistochemistry and Western blotting. Strong GLUT-5 immunoreactivity was observed in the cytoplasm of spermatocytes, spermatids, and spermatozoa, while weak staining was seen in spermatogonia. No GLUT-5 expression was detected in Leydig or Sertoli cells. Staining intensity varied significantly by month, with the highest levels observed in August (p < 0.05), exceeding those in July and September. Western blotting identified two GLUT-5 isoforms (55 and 100 kDa), with relative intensities that changed across the reproductive timeline. In parallel, morphometric analysis revealed that the height of the germinal epithelium and the diameter of the seminiferous tubules were significantly greater in July than in August and September, reflecting peak spermatogenic activity. These findings suggest that the seasonal regulation of fructose transport, along with changes in testicular architecture, may support testicular function and sperm maturation. The differential expression of GLUT-5 isoforms may reflect their distinct roles in body growth, reproductive maturation, and seasonal testicular activity in Hipposiderid bats. Full article

Mitochondria are dynamic organelles that undergo repeated fusion and fission. We studied how the distribution and shape of mitochondria change during Drosophila spermatogenesis and whether factors that regulate their dynamics are necessary for these changes. Unlike the shortened mitochondria seen in mitosis, an interconnected network of elongated mitochondria forms before meiosis and is maintained during meiotic divisions. Mitochondria are evenly divided into daughter cells, relying on microtubules and F-actin. To explore the role of mitochondrial network structure in cell growth and meiosis, we depleted the mitochondrial fusion factors Opa1 and Marf and the morphology proteins Letm1 and EndoB in spermatocytes. This knockdown led to inhibited cell growth and failed meiosis. As a result, the spermatocytes differentiated into spermatids without completing meiosis. The knockdown also inhibited the cytoplasmic and nuclear accumulation of Cyclin B before meiosis, and Cdk1 was not fully activated at the onset of meiosis. Notably, ectopic overexpression of Cyclin B partially rescued the failure of meiosis. Many spermatids from the spermatocytes subjected to the knockdowns contained multiple smaller nuclei and abnormally shaped Nebenkerns. These findings suggest that mitochondrial network structure, maintained by fusion and morphology factors, is essential for meiosis progression and Nebenkern formation in Drosophila spermatogenesis. Full article

Background: Classical swine fever virus (CSFV) is a highly contagious and fatal disease in pigs and wild boars. While hunting and bait vaccination are effective for CSFV eradication, additional strategies are needed to control wild boar populations. This study aimed to develop an oral vaccine, Flc-LOM-GnRHx3, by inserting gonadotropin-releasing hormone (GnRH) epitopes into the Flc-LOM clone. Methods: The Flc-LOM-GnRHx3 strain was rescued from CPK cells and propagated to high titers in MDBK cells. Male boars (20 weeks old) received three doses (10^5.0 TCID₅₀/ml/dose) of Flc-LOM-GnRHx3 either orally or intramuscularly at 2-week intervals. Anti-CSFV E2 antibodies were detected via immunofluorescence and Western blotting. Results: Both vaccination routes induced anti-GnRH antibodies and reduced testosterone levels. Testis size and weight were slightly lower than controls, with seminiferous tubule and spermatid deformities observed in 52.5% of intramuscularly vaccinated pigs and 20.8% of orally vaccinated pigs. Conclusions: Flc-LOM-GnRHx3 demonstrates potential as a dual-function oral vaccine that can eradicate CSFV and impair reproductive capacity in wild boars, offering a novel approach for integrated disease control and population management. Full article

The apple snail Pila globosa is a widely distributed mollusc in tropical freshwater ecosystems, where it plays a crucial ecological role. This study examined the morphometric features, condition indices, and reproductive traits of P. globosa to gain insights into its population structure in the Ratargul Freshwater Swamp Forest, Bangladesh. Water quality parameters were recorded, and various morphometric measurements were analysed, including their correlations and seasonal variations. The mean values for shell length, shell weight, shell width, spiral length, base length, aperture length, aperture width, and soft tissue wet weight were 4.64 ± 0.97 cm, 38.29 ± 15.27 g, 3.56 ± 0.74 cm, 2.32 ± 0.51 cm, 3.33 ± 0.74 cm, 3.46 ± 0.64 cm, 2.01 ± 0.45 cm, and 18.05 ± 11.39 g, respectively. Linear regression analyses revealed strong correlations among length–length and length–weight parameters, indicating consistent growth patterns. Monthly frequency distributions showed distinct variations in shell size and form. The sex ratio was 1:1.23 (male–female), not significantly different from parity. Histological analysis during the rainy season revealed reproductive activity, including mature ova, previtellogenic and vitellogenic oocytes, and spermatogonia and spermatids. These findings enhance understanding of the species’ biology and its interaction with environmental conditions, offering valuable data for the conservation and management of freshwater mollusc populations in wetland ecosystems. Full article

Sperm flagellum defects are tightly associated with male infertility. Centriolar satellites are small multiprotein complexes that recruit satellite proteins to the centrosome and play an essential role in sperm flagellum biogenesis, but the precise mechanisms underlying this role remain unclear. Serologically defined colon cancer autoantigen protein 8 (SDCCAG8), which encodes a protein containing eight coiled-coil (CC) domains, has been associated with syndromic ciliopathies and male infertility. However, its exact role in male infertility remains undefined. Here, we used an Sdccag8 mutant mouse carrying a CC domains 5–8 truncated mutation (c.1351–1352insG p.E451GfsX467) that models the mutation causing Senior–Løken syndrome (c.1339–1340insG p.E447GfsX463) in humans. The homozygous Sdccag8 mutant mice exhibit male infertility characterized by multiple morphological abnormalities of the flagella (MMAF) and dysmorphic structures in the sperm manchette. A mechanistic study revealed that the SDCCAG8 protein is localized to the manchette and centrosomal region and interacts with PCM1, the scaffold protein of centriolar satellites, through its CC domains 5–7. The absence of the CC domains 5–7 in mutant spermatids destabilizes PCM1, which fails to recruit satellite components such as Bardet–Biedl syndrome 4 (BBS4) and centrosomal protein of 131 kDa (CEP131) to satellites, resulting in defective sperm flagellum biogenesis, as BBS4 and CEP131 are essential to flagellum biogenesis. In conclusion, this study reveals the central role of SDCCAG8 in maintaining centriolar satellite integrity during sperm flagellum biogenesis. Full article

This study investigated the effects of dietary Gonadotropin-releasing hormone (GnRH) and domperidone on the reproductive performance of Devario devario during a 40-day trial. Five treatment groups received varying doses of GnRH (100, 50, 25, 12.5 µg/kg body weight) in combination with domperidone (50, 25, 12.5, 6.25 mg/kg body weight), embossed in a gel-based diet alongside a control group without the exogenous hormones. Reproductive performance was examined by measuring the gonadosomatic index, fecundity, reproductive hormone levels, and histological features of the gonads, blood parameters, and antioxidant enzyme activity. The T1 group (100 µg GnRH + 50 mg domperidone) exhibited the highest GSI in both sexes. The histological analysis of testes from T1, T2 (50 µg GnRH + 25 mg domperidone), and T3 (25 µg GnRH + 12.5 mg domperidone) groups revealed an increased presence of late-stage spermatids and spermatozoa. In females, the T2 group produced the highest proportion of advanced-stage oocytes and demonstrated the greatest absolute fecundity (1300 ± 23 eggs). However, the control group showed the highest fertilization and hatching rates. Testosterone levels were significantly elevated in the T3 group, while vitellogenin levels increased in the T1 and T2 groups. Antioxidant enzyme activity varied, with the T1 group displaying higher superoxide dismutase activity in gills and liver, and the T2 group showing increased SOD activity in muscle and brain. Improvements in haematological parameters were observed across all treatments. These results suggest that an optimal dose of 50 µg GnRH + 25 mg domperidone can enhance reproductive performance in D. devario. Full article