Context Sperm head–tail linkage is essential for maintaining sperm integrity and male fertility. Although CFAP47 is associated with multiple morphological abnormalities of the sperm flagella, its role in sperm head–tail coupling remains unclear. Aims This study aimed to investigate the role of CFAP47 in sperm head–tail connection. Methods A Cfap47 knockout mouse model was established to assess sperm motility and morphology. Molecular docking, co-immunoprecipitation and proximity ligation assays were used to investigate the relationships of CFAP47, Septin12 and SUN5. Key results Cfap47 knockout mice exhibited impaired sperm motility and severe sperm morphological defects, with approximately 70% of sperm displaying abnormal head–tail connection or decapitation. Co-immunoprecipitation and proximity ligation assays demonstrated that CFAP47 cooperates with Septin12 and SUN5. CFAP47 deficiency reduced the protein expression levels and affected their localization at the sperm head–tail junction. Conclusions CFAP47 is essential for sperm head–tail coupling. Implications These findings provide new insight into the molecular basis of sperm head–tail connection.
Context Declining fertility in aging cows is associated with impaired uterine function, but the relationship between immune remodeling and fibrosis-associated uterine changes remains poorly understood. Aims We hypothesized that the uterus of old multiparous cows exhibits coordinated immune–fibrosis-associated remodeling characterized by increased concurrent immunoreactivity of the macrophage markers CD86 and CD163 with HSP47. To test this hypothesis, we quantified CD86-, CD163-, HSP47-, and concurrent immunoreactive profiles throughout the endometrium and myometrium. Additional qualitative αSMA analysis was performed to further characterize CD86/HSP47- and CD163/HSP47-immunoreactive profiles. Methods Caruncular (CAR) and intercaruncular (ICAR) endometrium and myometrium were collected from young nulliparous heifers (n = 6) and old multiparous cows (n = 6). Multiplex immunofluorescence with tyramide signal amplification was used to detect CD86, CD163, and HSP47. Key results Concurrent macrophage marker/HSP47-immunoreactive profiles were increased throughout the uterus of old multiparous cows compared with young nulliparous heifers and enriched beneath the luminal epithelium, around endometrial glands, in connective tissue, and in the myometrium. Qualitative analysis further showed αSMA immunoreactivity within many CD86/HSP47- and CD163/HSP47-immunoreactive profiles in the CAR and ICAR. Conclusions Compared with young nulliparous heifers, old multiparous cows showed increased concurrent immunoreactivity of macrophage markers with HSP47 throughout the uterus, consistent with coordinated immune–fibrosis-associated remodeling. Qualitative αSMA analysis provides additional support for the fibrosis-associated component of this remodeling. Implications Coordinated immune–fibrosis-associated remodeling may contribute to age-associated changes in uterine function and represent a potential target for preserving reproductive longevity in cattle.
Context In mares, post-breeding endometritis is a major cause of embryo mortality. In other species, endometrial function and pathology seem to involve heat shock protein-90 (HSP90), a factor regulated by heat shock transcription factor-1 (HSF-1). Aims To study the relationships between HSP90 and HSF-1 and post-insemination endometritis. Methods Endometrium was sampled at oestrus without artificial insemination (AI) and at 2 h and 4 h after AI. Immunohistochemistry and image analysis were used to localise and quantify HSP90 and HSF-1 in luminal and glandular epithelium; in stroma, immuno-positive leucocytes and fibroblasts were counted. Key results Both HSP90 and HSF-1 were expressed in the cytoplasm and the nucleus of luminal epithelial and stromal cells. In the glandular epithelium, HSP90 immunoexpression increased above the control (no AI) values, 2 h and 4 h after AI. In contrast, HSF-1 immunoexpression decreased 2 h and 4 h after AI. At 2 and 4 h after AI, the numbers of HSP90- and HSF-1-positive leucocytes and fibroblasts exceeded control values. Conclusions Changes in HSP90 and HSF-1 expression in endometrium after AI are associated with endometrial inflammation. Their presence in the cytoplasm and nucleus (luminal and glandular epithelial cells, fibroblasts, leucocytes) suggests roles in cytosolic protein interactions and DNA regulation. Their expression in luminal and glandular epithelium, and in stromal cells, suggests roles in the regulation of endometrial repair and remodelling. Implications The relationships between HSP90 and HSF-1 and the development of post-insemination endometritis suggest that these proteins can be targets for prevention or treatment of persistent endometritis.
During oocyte growth, substantial epigenetic programming occurs to establish a distinctive epigenome including appropriately patterned DNA methylation and histone modifications. Oocyte epigenetic programming must be tightly spatiotemporally regulated to ensure that a wide variety of epigenetic modifiers correctly establish their respective modifications to mediate precise control of gene expression. Furthermore, epigenetic modifications in oocytes include canonical and non-canonical genomic imprints, which are transmitted through meiosis to offspring. Significantly, disruptions in oocyte epigenetic programming can cause aberrant developmental outcomes in the next generation mediated by altered imprinting. Polycomb repressive complex 2 is an important epigenetic modifier that establishes histone 3 lysine 27 trimethylation and non-canonical imprints during mouse oogenesis, which are important for normal offspring development. While it is widely recognised that altered oocyte epigenetic programming can disrupt offspring development, mechanisms controlling maternal epigenetic inheritance remain poorly understood. The possibility remains that non-canonical imprinting exists in humans, although this requires confirmation. This review discusses mouse and human oocyte epigenetic programming including interactions between various epigenetic modifiers and modifications that form the unique oocyte epigenome. Understanding how oocyte epigenetic programming is regulated will be crucial in discerning how changes to the oocyte epigenome can disrupt epigenetic memory and alter developmental outcomes in offspring.
CONTEXT:Inhibiting phosphodiesterase (PDE) activity to increase cyclic adenosine monophosphate (cAMP) concentrations is a core strategy in artificial sperm activation. PDE3, a key member of the PDE family, comprises two subtypes, PDE3A and PDE3B. However, their specific expression patterns and functions in human sperm remain incompletely understood. AIMS:To analyze the expression characteristics of PDE3A and PDE3B in human sperm and investigate the regulatory effects of PDE3 inhibitor milrinone on asthenozoospermic sperm function and the related mechanisms. METHODS:The expression of PDE3A and PDE3B was detected using reverse transcription polymerase chain reaction (RT-PCR), western blot and immunofluorescence. Changes in asthenozoospermic sperm functions after milrinone treatment were detected using computer-assisted sperm analysis (CASA), methylcellulose viscous penetration assay, and fluorescein isothiocyanate-conjugated peanut agglutinin (FITC-PNA) staining. Moreover, intracellular factors closely correlated with sperm function regulation were measured using enzyme-linked immunosorbent assay (ELISA), flow cytometry, and metabolome analysis. KEY RESULTS:PDE3B expression level was greater than was the expression level of PDE3A in human sperm. Sperm function analysis showed that milrinone significantly enhanced asthenozoospermic sperm motility, mucus penetration ability, and the acrosome reaction. With respect to intracellular signals, milrinone activated the cAMP‒protein kinase A (PKA) signaling pathway, and metabolomic analysis showed that milrinone-induced differentially abundant metabolites (DAMs) were associated with the citrate cycle and fatty acid degradation pathways, suggesting that it regulates energy metabolism. CONCLUSIONS:These results demonstrated that milrinone primarily targets PDE3B to improve asthenozoospermic sperm function by regulating cAMP‒PKA signaling pathway and energy metabolism. IMPLICATIONS:The present study has gained new insight into the molecular basis of cAMP signaling regulation in human sperm and provides theoretical and experimental support for the potential application of milrinone for asthenozoospermic sperm activation.
