Non-obstructive azoospermia is a common condition associated with significant health risks, including increased mortality, cancer, and chronic diseases such as metabolic and cardiovascular disorders. This review aims to highlight the potential health challenges faced by men with this condition compared to fertile counterparts. Through a comprehensive bibliographic search on PubMed, using the following algorithm: ("infertility, male" [MeSH Terms] OR "azoospermia" [MeSH Terms]) AND ("mortality" [MeSH Terms] OR "neoplasms" [MeSH Terms] OR "chronic disease" [MeSH Terms] OR "diabetes mellitus" [MeSH Terms] OR "heart diseases" [MeSH Terms]), we analyzed existing literature to explore the associations between infertility, specifically azoospermia, and adverse health outcomes. Findings indicate that infertile men are at a higher risk of death, various cancers (particularly testicular cancer), metabolic syndrome, diabetes, hypogonadism, and cardiovascular disease. Although research specifically addressing azoospermia is limited, available studies support the notion that men with this condition may experience heightened health vulnerabilities. Given these risks, it is imperative for healthcare professionals, especially urologists, to conduct thorough health assessments for men diagnosed with azoospermia. Informing patients of these potential health issues and integrating comprehensive evaluations into their care can facilitate early detection and intervention for life-threatening conditions. Ultimately, men with azoospermia should receive ongoing monitoring to address their specific health concerns, thus improving their long-term health outcomes.

Lymphomas represent one of the most common malignant diseases in young men and an important issue is how treatments will affect their reproductive health. It has been hypothesized that chemotherapies, similarly to environmental chemicals, may alter the spermatogenic epigenome. Here, we report the genomic and epigenomic profiling of the sperm DNA from a 31-year-old Hodgkin lymphoma patient who faced recurrent spontaneous miscarriages in his couple 11-26 months after receiving chemotherapy with adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD). In order to capture the potential deleterious impact of the ABVD treatment on mutational and methylation changes, we compared sperm DNA before and 26 months after chemotherapy with whole-genome sequencing (WGS) and reduced representation bisulfite sequencing (RRBS). The WGS analysis identified 403 variants following ABVD treatment, including 28 linked to genes crucial for embryogenesis. However, none were found in coding regions, indicating no impact of chemotherapy on protein function. The RRBS analysis identified 99 high-quality differentially methylated regions (hqDMRs) for which methylation status changed upon chemotherapy. Those hqDRMs were associated with 87 differentially methylated genes, among which 14 are known to be important or expressed during embryo development. While no variants were detected in coding regions, promoter regions of several genes potentially important for embryo development contained variants or displayed an altered methylated status. These might in turn modify the corresponding gene expression and thus affect their function during key stages of embryogenesis, leading to potential developmental disorders or miscarriages.

Varicocele (VC) is a common cause of male infertility, yet there is a lack of molecular information for VC-associated male infertility. This study investigated alterations in the seminal plasma metabolomic and lipidomic profiles of infertile male VC patients. Twenty infertile males with VC and twenty-three age-matched healthy controls (HCs) were recruited from Peking Union Medical College Hospital (Beijing, China) between October 2019 and April 2021. Untargeted metabolite and lipid profiles from seminal plasma were analyzed using mass spectrometry. Four hundred and seventy-six metabolites and seventeen lipids were significantly different in infertile male VC patients compared to HCs. The top enriched pathways among these significantly different metabolites are protein digestion and absorption, aminoacyl-transfer RNA (tRNA) biosynthesis, and biosynthesis of amino acids. Different key lipid species, including triglyceride (TG), diacylglycerol (DG), ceramides (Cer), and phosphatidylserine (PS), varied between VC and HC groups. The distinct metabolites and lipids were moderately correlated. DL-3-phenyllactic acid is a potential diagnostic biomarker for VC-related male infertility (area under the curve [AUC] = 0.893), positively correlating with sperm count, concentration, and motility. Furthermore, DL-3-phenyllactic acid is the only metabolite shared by all four comparisons (VC vs HC, VC-induced oligoasthenospermia [OAS] vs VC-induced asthenospermia [AS], OAS vs HC, and AS vs HC). DL-3-phenyllactic acid significantly decreased in OAS than AS. Metabolite-targeting gene analysis revealed carbonic anhydrase 9 (CA9) might be the strongest candidate associated with the onset and severity of VC. The seminal plasma metabolite and lipid profiles of infertile males with VC differ significantly from those of HCs. DL-3-phenyllactic acid could be a promising biomarker.

To evaluate the therapeutic effect of a modified Devine procedure with a subcutaneous sliding fixation method for the treatment of congenital concealed penis, we retrospectively selected 45 patients with congenital concealed penises who were admitted to General Hospital of Ningxia Medical University (Yinchuan, China) between September 2020 and November 2023. In all cases, the penis was observed to be short, and retracting the skin at the base revealed a normal penile body, which immediately returned to its original position upon release. All patients underwent the modified Devine procedure with subcutaneous sliding fixation and completed a 12-week postoperative follow-up. A statistically significant increase in penile length was observed postoperatively, with the median length increasing from 4.0 (interquartile range [IQR]: 3.5-4.8; 95% confidence interval [CI]: 3.9-4.4) cm to 8.0 (IQR: 7.8-8.0; 95% CI: 7.7-7.9) cm, with P < 0.001. The parents were satisfied with the outcomes, including increased penile length, improved hygiene, and enhanced esthetics. Except for mild foreskin edema in all cases, no complications (such as infections, skin necrosis, or penile retraction) were observed. The edema was resolved within 4 weeks after the operation. This study demonstrates that the modified Devine procedure utilizing the subcutaneous sliding fixation method yields excellent outcomes with minimal postoperative complications, reduced penile retraction, and high satisfaction rates among patients and their families.

Researchers commonly use cyclization recombination enzyme/locus of X-over P1 (Cre/loxP) technology-based conditional gene knockouts of model mice to investigate the functional roles of genes of interest in Sertoli and Leydig cells within the testis. However, the shortcomings of these genetic tools include high costs, lengthy experimental periods, and limited accessibility for researchers. Therefore, exploring alternative gene silencing techniques is of great practical value. In this study, we employed adeno-associated virus (AAV) as a vector for gene silencing in Sertoli and Leydig cells. Our findings demonstrated that AAV serotypes 1, 8, and 9 exhibited high infection efficiency in both types of testis cells. Importantly, we discovered that all three AAV serotypes exhibited exquisite specificity in targeting Sertoli cells via tubular injection while demonstrating remarkable selectivity in targeting Leydig cells via interstitial injection. We achieved cell-specific knockouts of the steroidogenic acute regulatory (Star) and luteinizing hormone/human chorionic gonadotropin receptor (Lhcgr) genes in Leydig cells, but not in Sertoli cells, using AAV9-single guide RNA (sgRNA)-mediated gene editing in Rosa26-LSL-Cas9 mice. Knockdown of androgen receptor (Ar) gene expression in Sertoli cells of wild-type mice was achieved via tubular injection of AAV9-short hairpin RNA (shRNA)-mediated targeting. Our findings offer technical approaches for investigating gene function in Sertoli and Leydig cells through AAV9-mediated gene silencing.

The circadian clock is an important internal time regulatory system for a range of physiological and behavioral rhythms within living organisms. Testosterone, as one of the most critical sex hormones, is essential for the development of the reproductive system, maintenance of reproductive function, and the overall health of males. The secretion of testosterone in mammals is characterized by distinct circadian rhythms and is closely associated with the regulation of circadian clock genes. Here we review the central and peripheral regulatory mechanisms underlying the influence of circadian clock genes upon testosterone synthesis. We also examined the specific effects of these genes on the occurrence, development, and treatment of common male diseases, including late-onset hypogonadism, erectile dysfunction, male infertility, and prostate cancer.

Recent studies have shown that shorter periods of ejaculatory abstinence may enhance certain sperm parameters, but the molecular mechanisms underlying these improvements are still unclear. This study explored whether reduced abstinence periods could improve semen quality, particularly for use in assisted reproductive technologies (ART). We analyzed semen samples from men with normal sperm counts (n = 101) and those with low sperm motility or concentration (n = 53) after 3-7 days of abstinence and then after 1-3 h of abstinence, obtained from the Reproductive & Genetic Hospital of CITIC-Xiangya (Changsha, China). Physiological and biochemical sperm parameters were evaluated, and the dynamics of transfer RNA (tRNA)-derived fragments (tRFs) were analyzed using deep RNA sequencing in five consecutive samples from men with normal sperm counts. Our results revealed significant improvement in sperm motility and a decrease in the DNA fragmentation index after the 1- to 3-h abstinence period. Additionally, we identified 245 differentially expressed tRFs, and the mitogen-activated protein kinase (MAPK) signaling pathway was the most enriched. Further investigations showed significant changes in tRF-Lys-TTT and its target gene mitogen-activated protein kinase kinase 2 (MAP2K2), which indicates a role of tRFs in improving sperm function. These findings provide new insights into how shorter abstinence periods influence sperm quality and suggest that tRFs may serve as biomarkers for male fertility. This research highlights the potential for optimizing ART protocols and improving reproductive outcomes through molecular approaches that target sperm function.

Since the early days of assisted reproductive technology (ART), the importance of sperm processing, employed to separate the motile, morphologically normal sperm from the semen, has been shown to be beneficial. The aim of the semen processing technique has been to remove seminal plasma and facilitate capacitation. Additionally, the presence of leukocytes, bacteria, and dead spermatozoa has been shown to be detrimental as it may cause oxidative stress that has an adverse effect on oocyte fertilization and embryo development. Hence, removal of leukocytes, bacteria, and dead spermatozoa is an important step of sperm processing for assisted reproduction. Currently, several sperm processing techniques have been evolved and optimized in the field of assisted reproduction. The requirements for in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and testicular sperm extraction (TESE) are different than those of intrauterine insemination (IUI). The yield of as many motile, morphologically normal sperm as possible is a prerequisite for the success of IVF insemination procedure. In ICSI, where injection of a single spermatozoon into the oocyte is performed by the embryologist, sperm selection techniques play a crucial role in the ICSI procedure. Finally, sperm retrieval in TESE samples with very low number of sperm may be challenging and requires extra care during sample processing. Additionally, sperm cryopreservation is necessary in TESE cases in order to avoid multiple biopsies.

A growing global trend indicates a decline in semen quality, with a lack of physical activity identified as one of the contributing factors. Exercise is medication, and numerous studies have explored its effects on semen quality. However, there is no consensus on the most effective type and intensity of exercise for improving semen quality, owing to inconsistent findings across studies. These discrepancies may be attributable to variations in study populations (e.g., healthy versus infertile individuals) and research methodologies (e.g., observational versus interventional studies). This paper reviews the existing literature from the databases PubMed, Web of Science, and Google Scholar, reclassifying articles on their subject and research designs to delineate the relationship between exercise and semen quality. It also summarizes the mechanisms through which exercise influences semen quality, including hormonal regulation, oxidative stress, and inflammatory factors.