OBJECTIVE: To observe the effect of "Zhibian" (BL54)-to-"Shuidao" (ST28) needling technique on the reproductive function of the mice with poor ovarian response (POR) and explore the molecular mechanism of acupuncture on early embryos after in vitro fertilization-embryo transfer (IVF-ET) in POR mice. METHODS: Of 70 female C57BL/6 mice, 60 mice with regular estrous cycle were screened and 30 of them were randomly divided into a blank group, a model group, and an acupuncture group, 10 mice in each one. Mice in the model and acupuncture groups were administered with tripterygium glycosides suspension (50 mg·kg^-1·d^-1) via gavage for 2 weeks to prepare POR models; while in the blank group, the mice received an equal volume of 0.9% sodium chloride solution via gavage. After successful modeling, mice in the acupuncture group underwent "Zhibian" (BL54)-to-"Shuidao" (ST28) needling technique, once daily, for 20 min each time and lasting 2 consecutive weeks. After intervention completion, subsequently, all the three groups underwent ovulation induction, orbital blood collection, and ovary extraction and fresh denuded oocyte collection. Denuded oocytes, after incubated, together with the sperms from 15 male C57BL/6 mice, were transferred into the oviducts of 30 donor pseudopregnant C57BL/6 female mice via IVF-ET; and the embryonic tissue was collected on day 7 of implantation. After successful modeling and intervention completion, the general conditions of mice in each group were observed, and the estrous cycle disorder rate was compared among the groups. After intervention completion, the numbers of oocyte, ovarian wet weight and ovarian index were recorded in each group; the levels of anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2) in the serum were measured using ELISA; and ovarian morphology and mitochondrial ultrastructure were examined using HE staining and transmission electron microscopy. The transcriptome sequencing technology was employed to identify differentially expressed genes (DEGs) in early embryos of each group, followed by bioinformatics analysis; and the reversed DEGs with significant difference were verified using quantitative real-time PCR (qRT-PCR). RESULTS: After intervention, compared with the blank group, the mice in the model group presented poor spirits and declined water and food intake, reduced activity, the higher rate of estrous cycle disorder (P< 0.01); the decrease of the numbers of oocyte, ovarian wet weight, and ovarian index (P<0.01), reduced AMH and E2 in the serum (P<0.01), elevated FSH and LH in the serum (P<0.01); more atresia follicles in ovarian tissue, disorganized granulosa cells, reduced the numbers of mitochondria, vacuoles appeared and cristae breakage. When compared with the model group, in the acupuncture group, the spirits of mice, food intake and activity were improved, the rate of estrous cycle disorder was reduced (P<0.01); the numbers of oocyte, ovarian wet weight, and ovarian index were higher (P<0.01, P<0.05), the levels of AMH and E2 in the serum increased (P<0.01), the levels of FSH and LH in the serum decreased (P<0.01); the atresia follicles were reduced, the numbers of follicle increased at all levels, the numbers of mitochondria got higher, vacuoles and cristae breakage were declined. In comparison between the blank group and the model group, and between the model group and the acupuncture group, a total of 258 intersecting DEGs were identified, and 194 DEGs of them exhibited a trend of reversion before and after intervention. The top 5 reversed DEGs with significant difference included dexamethasone-induced Ras-related protein 1 (Rasd1), gene regulated by estrogen in breast cancer 1 (Greb1), leucine-rich repeat-containing G protein-coupled receptor 6 (Lgr6), Fraser syndrome 1 (Fras1), and apolipoprotein D (Apod). Compared with the blank group, the mRNA expression of Rasd1, Greb1, Lgr6, Fras1 and Apod in embryonic tissues decreased in the model group (P<0.01, P<0.05); and when compared with the model group, the mRNA expression of Rasd1, Greb1, Lgr6, Fras1 and Apod in embryonic tissues increased in the acupuncture group (P<0.05, P<0.01). These findings were consistent with the DEGs screening results. Gene ontology (GO) analysis revealed that the reversed genes of co-expression were primarily participated in the biological processes such as myoblast differentiation, endocardial cushion development, and cardiac morphogenesis. Kyoto encyclopedia of genes and genomes (KEGG) analysis indicated that the reversed genes of co-expression are enriched in the Wnt signaling pathway, and they were associated with various types of cardiac diseases. CONCLUSION The "Zhibian" (BL54)-to-"Shuidao" (ST28) needling technique may ameliorate the decline of ovarian response in mice with POR, promote normal follicle development and ovulation, thereby improve embryo quality and reduce the risk of developmental defects and deformity in the organs such as the embryonic heart. The underlying mechanism may be related to the regulation of the expression pattern of embryonic key genes through the Wnt signaling pathway.
Animals ; Female ; Mice ; Mice, Inbred C57BL ; Acupuncture Therapy ; Ovary/physiopathology* ; Humans ; Fertilization in Vitro ; Transcriptome ; Embryo Transfer ; Infertility, Female/physiopathology*

Male infertility has become a global concern, accounting for 20-70% of infertility. Dysfunctional spermatogenesis is the most common cause of male infertility; thus, treating abnormal spermatogenesis may improve male infertility and has attracted the attention of the medical community. Mitochondria are essential organelles that maintain cell homeostasis and normal physiological functions in various ways, such as mitochondrial oxidative phosphorylation (OXPHOS). Mitochondrial OXPHOS transmits electrons through the respiratory chain, synthesizes adenosine triphosphate (ATP), and produces reactive oxygen species (ROS). These mechanisms are vital for spermatogenesis, especially to maintain the normal function of testicular Sertoli cells and germ cells. The disruption of mitochondrial OXPHOS caused by external factors can result in inadequate cellular energy supply, oxidative stress, apoptosis, or ferroptosis, all inhibiting spermatogenesis and damaging the male reproductive system, leading to male infertility. This article summarizes the latest pathological mechanism of mitochondrial OXPHOS disorder in testicular Sertoli cells and germ cells, which disrupts spermatogenesis and results in male infertility. In addition, we also briefly outline the current treatment of spermatogenic malfunction caused by mitochondrial OXPHOS disorders. However, relevant treatments have not been fully elucidated. Therefore, targeting mitochondrial OXPHOS disorders in Sertoli cells and germ cells is a research direction worthy of attention. We believe this review will provide new and more accurate ideas for treating male infertility.
Male ; Humans ; Infertility, Male/metabolism* ; Oxidative Phosphorylation ; Mitochondria/metabolism* ; Spermatogenesis/physiology* ; Sertoli Cells/metabolism* ; Oxidative Stress/physiology* ; Animals ; Reactive Oxygen Species/metabolism*

BACKGROUND: Infertility is a burdensome, often overlooked condition. This study aimed to investigate the global distribution and trends in the burden of infertility from 1990 to 2021. METHODS: We obtained data on the prevalence and years lived with disability (YLDs) related to infertility from the Global Burden of Disease 2021 study and evaluated them by calculating the estimated annual percentage change in age-standardized rates. We investigated the relationship between sociodemographic index (SDI) and the burden of infertility on the global, regional, and national levels. RESULTS: In 2021, there were 143,261,562 female and 55,481,380 male infertility cases worldwide, respectively. In China, female and male infertility cases accounted for 23.59% and 21.47% of the global totals, reaching 33,795,944 and 11,909,889, respectively. Compared with 2019, the global number of female and male infertility cases increased by 5,286,227 in females and 2,017,271 in males. In contrast, China saw a decline in both female and male infertility cases, with reductions of 698,735 and 154,591, respectively. From 1990 to 2021, the age-standardized prevalence rate (ASPR) and age-standardized YLDs rate (ASYR) for female infertility both increased by 0.59% annually, whereas these two corresponding indicators for male infertility increased by 0.50% annually worldwide. The burden of female infertility was consistently higher than that of male infertility and demonstrated a faster rate of increase. East Asia had the highest ASPR and ASYR for female infertility, whereas Eastern Europe had the highest metrics for male infertility. A horizontal S-shaped association was observed between the SDI and ASPR and ASYR of infertility, with a rapid decline in the infertility burden when the SDI exceeded 0.7. CONCLUSIONS The global burden of infertility has increased over the years, with a higher burden on women and underdeveloped regions. These findings emphasize the need to prioritize healthcare for patients with infertility to address the rising burden.
Humans ; Female ; Male ; Global Burden of Disease ; Prevalence ; Infertility/epidemiology* ; Adult ; Infertility, Male/epidemiology* ; Persons with Disabilities/statistics & numerical data* ; Middle Aged ; Infertility, Female/epidemiology* ; China/epidemiology* ; Disability-Adjusted Life Years

Recently, male reproductive health has attracted extensive attention, with the adverse effects of circadian disruption on male fertility gradually gaining recognition. However, the mechanism by which circadian disruption leads to damage to male reproductive system remains unclear. In this review, we first summarized the dual regulatory roles of circadian clock genes on the male reproductive system: (1) circadian regulation of testosterone synthesis via the hypothalamic-pituitary-testicular (HPT) and hypothalamic-pituitary-adrenal (HPA) axes; (2) non-circadian regulation of spermatogenesis. Next, we further listed the possible mechanisms by which circadian disruption impairs male fertility, including interference with the oscillatory function of the reproductive system, i.e., synchronization of the HPT axis, crosstalk between the HPT axis and the HPA axis, as well as direct damage to germ cells by disturbing the non-oscillatory function of the reproductive system. Future research using spatiotemporal omics, epigenomic assays, and neural circuit mapping in studying the male reproductive system may provide new clues to systematically unravel the mechanisms by which circadian disruption affects male reproductive system through circadian clock genes.
Male ; Humans ; Animals ; Circadian Clocks/physiology* ; Hypothalamo-Hypophyseal System/physiology* ; Circadian Rhythm/genetics* ; Spermatogenesis/physiology* ; Pituitary-Adrenal System/physiology* ; Testis/physiology* ; Testosterone/biosynthesis* ; CLOCK Proteins ; Infertility, Male/physiopathology*

Varicocele is a prevalent condition in the infertile male population. However, to date, which patients may benefit most from varicocele repair is still a matter of debate. The purpose of this study was to evaluate whether certain preintervention sperm parameters are predictive of successful varicocele repair, defined as an improvement in total motile sperm count (TMSC). We performed a retrospective study on 111 patients with varicocele who had undergone varicocele repair, collected from the Department of Endocrinology, Metabolic Diseases and Nutrition, University of Catania (Catania, Italy), and the Unit of Urology at the Selcuk University School of Medicine (Konya, Türkiye). The predictive analysis was conducted through the use of the Brain Project, an innovative tool that allows a complete and totally unbiased search of mathematical expressions that relate the object of study to the various parameters available. Varicocele repair was considered successful when TMSC increased by at least 50% of the preintervention value. For patients with preintervention TMSC below 5 × 10 6 , improvement was considered clinically relevant when the increase exceeded 50% and the absolute TMSC value was >5 × 10 6 . From the preintervention TMSC alone, we found a model that predicts patients who appear to benefit little from varicocele repair with a sensitivity of 50.0% and a specificity of 81.8%. Varicocele grade and serum follicle-stimulating hormone (FSH) levels did not play a predictive role, but it should be noted that all patients enrolled in this study were selected with intermediate- or high-grade varicocele and normal FSH levels. In conclusion, preintervention TMSC is predictive of the success of varicocele repair in terms of TMSC improvement in patients with intermediate- or high-grade varicoceles and normal FSH levels.
Humans ; Varicocele/complications* ; Male ; Retrospective Studies ; Machine Learning ; Adult ; Treatment Outcome ; Sperm Count ; Infertility, Male/etiology* ; Sperm Motility ; Follicle Stimulating Hormone/blood* ; Young Adult

Infertility has become one of the most serious diseases worldwide, and 50% of this disease can be attributed to male-related factors. Spermatogenesis, by definition, is a complex process by which spermatogonial stem cells (SSCs) self-renew to maintain stem cell population within the testes and differentiate into mature spermatids. It is of great significance to uncover gene regulation and signaling pathways that are involved in the fate determinations of SSCs with aims to better understand molecular mechanisms underlying human spermatogenesis and identify novel targets for gene therapy of male infertility. Significant achievement has recently been made in demonstrating the signaling molecules and pathways mediating the fate decisions of mammalian SSCs. In this review, we address key gene regulation and crucial signaling transduction pathways in controlling the self-renewal, differentiation, and apoptosis of SSCs, and we illustrate the networks of genes and signaling pathways in SSC fate determinations. We also highlight perspectives and future directions in SSC regulation by genes and their signaling pathways. This review could provide novel insights into the genetic regulation of normal and abnormal spermatogenesis and offer molecular targets to develop new approaches for gene therapy of male infertility.
Humans ; Male ; Signal Transduction/physiology* ; Apoptosis/physiology* ; Spermatogenesis/physiology* ; Cell Differentiation ; Adult Germline Stem Cells/physiology* ; Spermatogonia/cytology* ; Gene Expression Regulation ; Animals ; Infertility, Male/genetics* ; Cell Self Renewal/genetics*

Spermatozoa have a highly complex RNA profile. Several of these transcripts are suggested as biomarkers for male infertility and contribute to early development. To analyze the differences between sperm RNA quantity and expression of protamine ( PRM1 and PRM2 ) and testis-specific histone 2B ( TH2B ) genes, spermatozoa from 33 patients who enrolled in assisted reproduction treatment (ART) program were analyzed. Sperm RNA of teratozoospermic (T), oligoteratozoospermic (OT), and normozoospermic (N) samples was extracted, and the differences in transcript levels among the study groups were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The correlations of total RNA per spermatozoon and the expression of the transcripts were evaluated in relation to sperm characteristics and preimplantation embryo development. The mean (±standard deviation) RNA amount per spermatozoon was 28.48 (±23.03) femtogram in the overall group and was significantly higher in the OT group than that in N and T groups. Total sperm RNA and gene expression of PRM1 and PRM2 genes were related to preimplantation embryo development and developmental arrest. Specific sperm characteristics were correlated with the expressions of PRM1 , PRM2 , or TH2B genes. We conclude that the sperm RNA amount and composition are important factors and might influence early embryonic development and also differ in different cases of male infertility.
Male ; Humans ; Protamines/metabolism* ; Spermatozoa/metabolism* ; Embryonic Development/genetics* ; Adult ; RNA/genetics* ; Histones/genetics* ; Infertility, Male/genetics* ; Teratozoospermia/genetics* ; Oligospermia/genetics*

Azoospermia is the complete absence of spermatozoa in the ejaculate in two or more semen analyses after centrifugation. Nonobstructive azoospermia (NOA) represents the most severe form of male factor infertility accounting for 10%-15% of cases and stems from an impairment to spermatogenesis. Understanding of the hypothalamic-pituitary-testicular axis has allowed NOA to be subcategorized by anatomic and/or pathophysiologic level. The etiologies of NOA, and therefore, the differential diagnoses when considering NOA as a cause of male factor infertility, can be subcategorized and condensed into several distinct classifications. Etiologies of NOA include primary hypogonadism, secondary hypogonadism, defects in androgen synthesis and/or response, defective spermatogenesis and sperm maturation, or a mixed picture thereof. This review includes up-to-date clinical, diagnostic, cellular, and histologic features pertaining to the multitude of NOA etiologies. This in turn will provide a framework by which physicians practicing infertility can augment their clinical decision-making, patient counseling, thereby improving upon the management of men with NOA.
Humans ; Azoospermia/diagnosis* ; Male ; Spermatogenesis/physiology* ; Hypogonadism/complications* ; Infertility, Male/etiology* ; Testis/pathology*

Primary ciliary dyskinesia (PCD) is a clinically rare, genetically and phenotypically heterogeneous condition characterized by chronic respiratory tract infections, male infertility, tympanitis, and laterality abnormalities. PCD is typically resulted from variants in genes encoding assembly or structural proteins that are indispensable for the movement of motile cilia. Here, we identified a novel nonsense mutation, c.466G>T, in cilia- and flagella-associated protein 300 ( CFAP300 ) resulting in a stop codon (p.Glu156*) through whole-exome sequencing (WES). The proband had a PCD phenotype with laterality defects and immotile sperm flagella displaying a combined loss of the inner dynein arm (IDA) and outer dynein arm (ODA). Bioinformatic programs predicted that the mutation is deleterious. Successful pregnancy was achieved through intracytoplasmic sperm injection (ICSI). Our results expand the spectrum of CFAP300 variants in PCD and provide reproductive guidance for infertile couples suffering from PCD caused by them.
Adult ; Female ; Humans ; Male ; Pregnancy ; China ; Ciliary Motility Disorders/genetics* ; Codon, Nonsense ; East Asian People/genetics* ; Exome Sequencing ; Homozygote ; Infertility, Male/genetics* ; Kartagener Syndrome/genetics* ; Pedigree ; Sperm Injections, Intracytoplasmic ; Cytoskeletal Proteins/genetics*

Multiple morphological abnormalities of the flagella (MMAF) represent a severe form of sperm defects leading to asthenozoospermia and male infertility. In this study, we identified a novel homozygous splicing mutation (c.871-4 ACA>A) in the adenylate kinase 7 (AK7) gene by whole-exome sequencing in infertile individuals. Spermatozoa from affected individuals exhibited typical MMAF characteristics, including coiled, bent, short, absent, and irregular flagella. Transmission electron microscopy analysis showed disorganized axonemal structure and abnormal mitochondrial sheets in sperm flagella. Immunofluorescence staining confirmed the absence of AK7 protein from the patients' spermatozoa, validating the pathogenic nature of the mutation. This study provides direct evidence linking the AK7 gene to MMAF-associated asthenozoospermia in humans, expanding the mutational spectrum of AK7 and enhancing our understanding of the genetic basis of male infertility.
Humans ; Male ; Sperm Tail/ultrastructure* ; Homozygote ; Consanguinity ; Asthenozoospermia/pathology* ; Infertility, Male/genetics* ; Mutation ; Pakistan ; Adenylate Kinase/genetics* ; Adult ; Pedigree ; RNA Splicing ; Exome Sequencing ; Spermatozoa