Sperm banking can preserve male fertility effectively, but the current conditions of sperm cryopreservation in China have not been investigated. This retrospective investigation was based on data collected at multiple...Sperm banking can preserve male fertility effectively, but the current conditions of sperm cryopreservation in China have not been investigated. This retrospective investigation was based on data collected at multiple centres in China from January 2003 to December 2008. The collected data included urogenital history, indication for cryopreservation, semen parameters, use rate, type of assisted reproductive technique (ART) treatment and pregnancy outcome. The study population included 1 548 males who had banked their semen during the study period at one of the clinics indicated above. Approximately 1.9% (30/1 548) of the cryopreserved semen samples were collected from cancer patients; about 88.8% (1 374/1 548) of the patients had banked their semen for ART and 8.6% (134/1 548) had a male infertility disease (such as anejaculation, severe oligozoospermia and obstructive azoospermia). The total use rate of cryopreserved semen was 22.7% (352/1 548), with 119 live births. The cancer group use rate was 6.7% (2/30), with one live birth by intracytoplasmic single sperm injection (ICSI). The ART group use rate was 23.2% (319/1 374), with 106 live births. The reproductive disease group use rate was 23.1% (31/134), with 12 live births. The semen parameters in each category varied; the cancer patient and infertility disease groups had poor semen quality. In vitro fertilization (IVF) and ICSI were the most common ART treatments for cryopreserved sperm. Semen cryopreservation as a salvage method is effective, but in many conditions it is underutilized, especially in cancer patients. Lack of awareness, urgency of cancer treatment and financial constraints are the main causes of the low access rate. The concept of fertility preservation should be popularized to make better use of this medical service in China.展开更多
Environmental contaminants such as persistent organic pollutants (POPs) are man-made bioaccumulative compounds with long half-lives that are found throughout the world as a result of heavy use in a variety of consum...Environmental contaminants such as persistent organic pollutants (POPs) are man-made bioaccumulative compounds with long half-lives that are found throughout the world as a result of heavy use in a variety of consumer products during the twentieth century. Wildlife and animal studies have long suggested adverse effects of exposure to these compounds on human reproductive health, which, according to the endocrine disrupter hypothesis, are ascribed to the compounds' potential to interfere with endocrine signaling, especially when exposure occurs during certain phases of fetal and childhood development. An extensive number of epidemiological studies have addressed the possible effects of exposure to POPs on male reproductive health, but the results are conflicting. Thus far, most studies have focused on investigating exposure and the different reproductive health outcomes during adulthood. Some studies have addressed the potential harmful effects of fetal exposure with respect to malformations at birth and/ or reproductive development, whereas only a few studies have been able to evaluate whether intrauterine exposure to POPs has long-term consequences for male reproductive health with measurable effects on semen quality markers and reproductive hormone levels in adulthood. Humans are not exposed to a single compound at a time, but rather, to a variety of different substances with potential divergent hormonal effects. Hence, how to best analyze epidemiological data on combined exposures remains a significant challenge. This review on POPs will focus on current knowledge regarding the potential effects of exposure to POPs during fetal and childhood life and during adulthood on male reproductive health, including a critical revision of the endocrine disruption hypothesis, a comment on pubertal development as part of reproductive development and a comment on how to account for combined exposures in epidemiological research.展开更多
Several animal studies indicate that mercury is a male reproductive toxicant, but human studies are few and contradictory. We examined semen characteristics and serum levels of reproductive hormones in relation to env...Several animal studies indicate that mercury is a male reproductive toxicant, but human studies are few and contradictory. We examined semen characteristics and serum levels of reproductive hormones in relation to environmental exposure to mercury. Blood and semen samples were collected from 529 male partners of pregnant women living in Greenland, Poland and Ukraine between May 2002 and February 2004. The median concentration of the total content of mercury in whole blood was 9.2 ng ml-1 in Greenland (0.2- 385.8 ng ml-1), 1.0 ng m1-1 in Poland (0.2-6.4 ng ml-z) and 1.0 ng ml-I in Ukraine (0.2-4.9 ng ml-1). We found a significantly positive association between the blood levels of mercury and serum concentration of inhibin B in men from Greenland (p=0.074, 95% confidence interval (CI)=0.021 to 0.126) and in an analysis including men from all three regions (p=0.067, 95% C1=0.024 to O. 110). The association may be due to beneficial effects of polyunsaturated fatty acids (PUFAs), which are contained in seafood and fish. No significant association (P〉O.05) was found between blood concentrations of mercury and any of the other measured semen characteristics (semen volume, total sperm count, sperm concentration, morphology and motility) and reproductive hormones (free androgen index {FAI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and LH xtestosterone) in any region. In conclusion, the findings do not provide evidence that environmental mercury exposure in Greenlandic and European men with median whole blood concentration up to 10 ng m1^-1 has adverse effects on biomarkers of male reproductive health.展开更多
Objective To report the first Bahrain national registry for ART treatments initiated from January 1, 2000 to December 31, 2005. Methods The "World Report on ART" forms, prepared by the International Committee for M...Objective To report the first Bahrain national registry for ART treatments initiated from January 1, 2000 to December 31, 2005. Methods The "World Report on ART" forms, prepared by the International Committee for Monitoring Assisted Reproductive Technology (ICMART), were filled from database records of all procedures and their respective outcome carried out at Banoon ART Centre, the Military Hospital, Bahrain during the period of 2000-2006. Results A total of 1490 completed cycles were performed. ICSI constituted 42.68% (636), IVF constituted 35.50% (529), while frozen-thawed embryo replacement cycles represented only 21.18% (325) of all ART cycles. The clinical pregnancy rates per transfer for IVF and ICSI cycles were 26.65% and 21.70%, respectively. The distribution of singleton, twin and triplet deliveries for IVF,, ICSI and FET combined were 80. 0%, 16.3% and 3.7%, respectively. The average delivery rate per clinical pregnancy for fresh and frozen cycles was 57.3%. As a result of ART services, 266 neonates were born. Complications of ART were solely due to ovarian hyperstimulation syndrome (OHSS) which constituted 2.26% of all aspirated cycles. Conclusion Multiple pregnancy rate was high due to transferring 〉3 embryos. Pregnancy loss and OHSS were relatively high thus preventative measures were recommended. This report paves the way for the other IVF centers in Bahrain to provide their own data for the national ART registry.展开更多
Melatonin,as a ubiquitous indoleamine hormone,is synthesized primarily by the pineal gland.It has diverse biological effects through quite complex mechanisms.More recently,studies have focused on the mechanism of mela...Melatonin,as a ubiquitous indoleamine hormone,is synthesized primarily by the pineal gland.It has diverse biological effects through quite complex mechanisms.More recently,studies have focused on the mechanism of melatonin in anti-reproductive toxicity/damage.Since melatonin possesses strong antioxidant and anti-apoptotic properties,researchers have examined its potential role in protecting against male reproductive toxicity/damage,which may be induced by chemotherapy or environmental toxicants and can lead to male infertility.In this article,recent progress regarding the protective effects of melatonin on male reproductive toxicity/damage is reviewed.展开更多
As genetic factors can hardly explain the changes taking place during short time spans, environmental and lifestyle-related factors have been suggested as the causes of time-related deterioration of male reproductive ...As genetic factors can hardly explain the changes taking place during short time spans, environmental and lifestyle-related factors have been suggested as the causes of time-related deterioration of male reproductive function. However, considering the strong heterogeneity of male fecundity between and within populations, genetic variants might be important determinants of the individual susceptibility to the adverse effects of environment or lifestyle. Although the possible mechanisms of such interplay in relation to the reproductive system are largely unknown, some recent studies have indicated that specific genotypes may confer a larger risk of male reproductive disorders following certain exposures. This paper presents a critical review of animal and human evidence on how genes may modify environmental effects on male reproductive function. Some examples have been found that support this mechanism, but the number of studies is still limited. This type of interaction studies may improve our understanding of normal physiology and help us to identify the risk factors to male reproductive malfunction. We also shortly discuss other aspects of gene-environment interaction specifically associated with the issue of reproduction, namely environmental and lifestyle factors as the cause of sperm DNA damage. It remains to be investigated to what extent such genetic changes, by natural conception or through the use of assisted reproductive techniques, are transmitted to the next generation, thereby causing increased morbidity in the offspring.展开更多
Objective To evaluate the risk of birth defects in children born following assisted reproductive technology (ART) and spontaneous conceptions. Methods This study carried out an updated systematic review to identify...Objective To evaluate the risk of birth defects in children born following assisted reproductive technology (ART) and spontaneous conceptions. Methods This study carried out an updated systematic review to identify papers published by August 2013 with data relating to birth defects of children conceived using ART (IVF and for ICSI) compared with those spontaneously conceived and also compared birth defects between subgroups of lVF and ICSI. Results Totally 76 studies were identified for review. The individual relative risk (RR) estimated for these studies ranged from 0.44 to 5.51, a signifieantly increased risk of birth defects was observed (RR=l.36, 95%CI=1.25-1.47) in ART compared with the spontaneously conceived group, which was also evident in the subgroup analysis. Among these studies, 16 studies simultaneously gave data of birth defects comparing IVF and ICSI children, which showed no difference in risk of combined effects (RR=0.90, 95%CI=0.80 1.02), but ICSI had a higher risk in subgroups of clinical research (RR=O. 76, 95%CI=0.65-0.89) and crude RR value (RR=O. 78, 95%CI=0.67 0.91). Conclusion Pooled results from all suitable published studies suggested that children born following ART were at increased risk of birth defects compared with spontaneous conceptions. There is no difference in birth defect risk between children conceived by IVF or 1CS1 using a summative analysis, however, 1CS1 had a significant higher risk in birth defect risk comparing with 1VF when using subgroup analyses of sample size and RR value.展开更多
Lessons from the occupational arena fdemonstrate the potential of industrial 4chemicals to damage human testicular function. An important but still unresolved question is whether low-level xenobiotic exposure of the ...Lessons from the occupational arena fdemonstrate the potential of industrial 4chemicals to damage human testicular function. An important but still unresolved question is whether low-level xenobiotic exposure of the general population poses a hazard. In this volume of the Asian Journal of Andrology, this issue is addressed by a series of reviews on xenobiotic exposure profiles, possible biological mechanisms, research methods and knowledge on impact of specific exposures. Interdisciplinary research fields as gene-environment interaction and male-mediated developmental toxicity is also addressed. Papers are cross-linked by answers to questions mutually put forward by the authors.展开更多
The cell cycle is a tightly coupled series of events that enable cells to grow and proliferate.Cyclin-dependent kinases(CDKs)play crucial roles in the cell cycle by enabling cells to transition between different phase...The cell cycle is a tightly coupled series of events that enable cells to grow and proliferate.Cyclin-dependent kinases(CDKs)play crucial roles in the cell cycle by enabling cells to transition between different phases when they are activated.Cell cycle proteins enhance the activity of CDKs,while natural CDK inhibitors(CDKIs)suppress them.The cell cycle continues in cycles under normal conditions,but when conditions change,cells halt or terminate the cell cycle.Tumors are tissues that grow out of control,and the mechanisms of various types of tumors are different;however,almost all tumor cells share several common characteristics,including proliferation,prevention of apoptosis and genomic instability.Cellular division is essential in the progression of cancer.A key characteristic of cancer is the uncontrolled growth of tumor cells,which is due to the erratic behavior of several proteins during the cell cycle.Therefore,cell cycle regulators are considered attractive targets for the treatment of cancer.The present analysis highlights proteins that play a direct role in controlling the tumor cell cycle,such as CDKs,and provides a brief overview of checkpoint kinases.The present review also discusses how cell cycle proteins contribute to cancer and describes some of the antitumor drugs that are being researched.展开更多
Selecting the embryo with the highest implantation potential is a top priority in in-vitro fertilization(IVF)centers.Few studies have explored the relationship between day 5 blastocyst morphokinetics and implantation ...Selecting the embryo with the highest implantation potential is a top priority in in-vitro fertilization(IVF)centers.Few studies have explored the relationship between day 5 blastocyst morphokinetics and implantation outcomes[1].Despite numerous time-lapse studies,the findings often conflict due to differences in patient demographics,lab conditions,and protocols,such as oxygen concentration[2].Thus,there is ongoing debate regarding which parameters are most predictive of implantation.展开更多
Diagnosis of male infertility has mainly been based on the World Health Organization (WHO) manual-based semen parameter's concentration, motility and morphology. It has, however, become apparent that none of these ...Diagnosis of male infertility has mainly been based on the World Health Organization (WHO) manual-based semen parameter's concentration, motility and morphology. It has, however, become apparent that none of these parameters are reliable markers for evaluation of the fertility potential of a couple. A search for better markers has led to an increased focus on sperm chromatin integrity testing in fertility work-up and assisted reproductive techniques. During the last couple of decades, numerous sperm DNA integrity tests have been developed. These are claimed to be characterized by a lower intraindividual variation, less intralaboratory and interlaboratory variation and thus less subjective than the conventional sperm analysis. However, not all the sperm chromatin integrity tests have yet been shown to be of clinical value. So far, the test that has been found to have the most stable clinical threshold values in relation to fertility is the sperm chromatin structure assay (SCSA), a flow cytometric test that measures the susceptibility of sperm DNA to acid-induced DNA denaturation in situ. Sperm DNA fragmentation as measured by SCSA has shown to be an independent predictor of successful pregnancy in first pregnancy planners as well as in couples undergoing intrauterine insemination, and can be used as a tool in investigation, counseling and treatment of involuntary childlessness. More conflicting data exist regarding the role of sperm DNA fragmentation in relation to fertilization, pre-embryo development and pregnancy outcome in in vitro fertilization and intracytoplasmic sperm injection (ICSI).展开更多
Aim: To investigate the prevalence of high levels of sperm DNA damage among men from infertile couples with both normal and abnormal standard semen parameters. Methods: A total of 350 men from infertile couples were...Aim: To investigate the prevalence of high levels of sperm DNA damage among men from infertile couples with both normal and abnormal standard semen parameters. Methods: A total of 350 men from infertile couples were assessed. Standard semen analysis and sperm chromatin structure assay (SCSA) were carried out. Results: Ninety-seven men (28% of the whole study group) had a DNA fragmentation index (DFI) 〉 20%, and 43 men (12%) had a DFI 〉 30%. In the group of men with abnormal semen parameters (n = 224), 35% had a DFI 〉 20%, and 16% had a DFI 〉 30%, whereas these numbers were 15% and 5%, respectively, in the group of men with normal semen parameters (n = 126). Men with low sperm motility and abnormal morphology had significantly higher odds ratios (ORs) for having a DFI 〉 20% (4.0 for motility and 1.9 for morphology) and DFI 〉 30% (6.2 for motility and 2.8 for morphology) compared with men with normal sperm motility and morphology. Conclusion: In almost one-third of unselected men from infertile couples, the DFI exceeded the level of 20% above which, according to previous studies, the in vivo fertility is reduced. A significant proportion of men with otherwise normal semen parameters also had high sperm DNA damage levels. Thus, the SCSA test could add to explaining causes of infertility in cases where semen analysis has not shown any deviation from the norm. We also recommend running the SCSA test to choose the appropriate assisted reproductive technique (ART).展开更多
It is well-documented that male overweight and obesity causes endocrine disorders that might diminish the male reproductive capacity; however, reports have been conflicting regarding the influence of male body mass in...It is well-documented that male overweight and obesity causes endocrine disorders that might diminish the male reproductive capacity; however, reports have been conflicting regarding the influence of male body mass index (BMI) on semen quality and the outcome of assisted reproductive technology (ART). The aim of this study was to investigate whether increased male BMI affects sperm quality and the outcome of assisted reproduction in couples with an overweight or obese man and a non-obese partner. Data was prospectively collected from 612 infertile couples undergoing ART at a Danish fertility center. Self-reported information on paternal height and weight were recorded and BMI was calculated. The men were divided into four BMI categories: underweight BMI 〈 20 kgm^-2, normal BMI 20-24.9 kg m^-2, overweight BMI 25-29.9 kgm^-2 and obese BMI 〉 30 kgm^-2. Conventional semen analysis was performed according to the World Health Organization guideline and sperm DNA integrity was analyzed by the Sperm Chromatin Structure Assay (SCSA). No statistically significant effect of male BMI was seen on conventional semen parameters (sperm concentration, total sperm count, seminal volume and motility) or on SCSA-results. Furthermore, the outcome of ART regarding fertilization rate, number of good quality embryos (GQE), implantation and pregnancy outcome was not influenced by the increasing male BMIo展开更多
Male reproductive function is impaired during end-stage renal disease (ESRD). Disturbance of the hypothalamic-pituitary-gonadal axis, and therefore the regulation of sex hormones, is one of the major causes. Our foc...Male reproductive function is impaired during end-stage renal disease (ESRD). Disturbance of the hypothalamic-pituitary-gonadal axis, and therefore the regulation of sex hormones, is one of the major causes. Our focus was to include antimLillerian hormone (AMH) and inhibin B concentrations. Twenty male patients on hemodialysis, median age 40 (26-48) years, were analyzed for follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, sex hormone-binding globulin (SHBG), testosterone, estradiol, AMH and inhibin B levels. We used 144 proven fertile men, median age 32 (19-44) years as a control group and analyzed differences using multiple linear regression. Males with ESRD demonstrated higher mean values for prolactin, 742 versus normal 210 mlE 1-1 (95% confidence interval (Cl): 60.3, 729), LH, 8.87 versus normal 4.5 IE 1-1 (95% Ch 2.75, 6.14), and estradiol 89.7 versus normal 79.0 pmol 1-1 (95% CI: -1.31, -0.15). Mean value for AMH was lower, 19.5 versus normal 47.3 pmol 1-1 (95% Cl. -37.6, -11.6). There were no differences found for FSH, SHBG, inhibin B and testosterone. The most important difference was found for AMH, a marker of Sertoli cell function in the testes, which decreased by close to 60% when compared with controls. Combined with an increase in LH, these findings may indicate a dysfunction of Sertoli cells and an effect on Leydig cells contributing to a potential mechanism of reproductive dysfunction in men with ESRD.展开更多
An ideal animal model of azoospermia would be a powerful tool for the evaluation of spermatogonial stem cell(SSC)transplantation.Busulfan has been commonly used to develop such a model,but 30%–87%of mice die when adm...An ideal animal model of azoospermia would be a powerful tool for the evaluation of spermatogonial stem cell(SSC)transplantation.Busulfan has been commonly used to develop such a model,but 30%–87%of mice die when administered an intraperitoneal injection of 40 mg kg^?1.In the present study,hematoxylin and eosin staining,Western blot,immunofluorescence,and quantitative real-time polymerase chain reaction were used to test the effects of busulfan exposure in a mouse model that received two intraperitoneal injections of busulfan at a 3-h interval at different doses(20,30,and 40 mg kg^?1)on day 36 or a dose of 40 mg kg^?1 at different time points(0,9,18,27,36,and 63 days).The survival rate of the mice was 100%.When the mice were treated with 40 mg kg^?1 busulfan,dramatic SSC depletion occurred 18 days later and all of the germ cells were cleared by day 36.In addition,the gene expressions of glial cell line-derived neurotrophic factor(GDNF),fibroblast growth factor 2(FGF2),chemokine(C-X-C Motif)ligand 12(CXCL12),and colony-stimulating factor 1(CSF1)were moderately increased by day 36.A 63-day,long-term observation showed the rare restoration of endogenous germ cells in the testes,suggesting that the potential period for SSC transplantation was between day 36 and day 63.Our results demonstrate that the administration of two intraperitoneal injections of busulfan(40 mg kg^?1 in total)at a 3-h interval to mice provided a nonlethal and efficient method for recipient preparation in SSC transplantation and could improve treatments for infertility and the understanding of chemotherapy-induced gonadotoxicity.展开更多
Diabetic erectile dysfunction(DED)is a common complication of diabetes mellitus,significantly impairing the quality of life of patients.The conventional clinical treatment still has limitations.Stem cells(SCs),as a ty...Diabetic erectile dysfunction(DED)is a common complication of diabetes mellitus,significantly impairing the quality of life of patients.The conventional clinical treatment still has limitations.Stem cells(SCs),as a type of cells with multidirectional or directional differentiation capability and sustainable selfrenewal potential,are widely used in regenerative medicine and tissue engineering.With the continuous update of regenerative medicine theory and the success of animal experiments,SCs as a treatment for male erectile dysfunction,especially DED,have attracted widespread attention because of curable possibility.This review focus on the current progress in the clinical application of SC treatment for DED.Moreover,we summarize the development prospects of SCs in the field of DMED therapy.展开更多
Long-term gonadotropin-releasing hormone agonist(Gn RHa) administration before in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI) in infertile women with endometriosis or adenomyosis significantl...Long-term gonadotropin-releasing hormone agonist(Gn RHa) administration before in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI) in infertile women with endometriosis or adenomyosis significantly enhanced the chances of pregnancy in both fresh and frozen embryo transfer cycles. We hypothesized that long-term Gn RHa treatment might also be beneficial for the idiopathic repeated implantation failure(RIF) patients. In the 21 patients receiving Gn RHa and hormone replacement therapy(G-HRT) protocols for frozen embryo transfer, their data were compared with those of the 56 of frozen/fresh cycles they had previously undergone(previous protocols). Comparison showed that the finial results were significantly better with G-HRT protocols than with their previous protocols, with pregnancy rate, clinical pregnancy rate, implantation rate and on-going pregnancy rate being 70%, 60%, 40% and 38% respectively with G-HRT protocols, against 17%, 11%, 6.3% and 5% with previous protocols. The results showed that hormonally controlled endometrial preparation with prior Gn RHa suppression could be used for patients who had experienced repeated failures of IVF treatment despite having morphologically optimal embryos, and the treatment may help increase the receptivity of the endometrium in these patients.展开更多
The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone (GnRH) a...The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone (GnRH) agonist were assessed. A retrospective cohort analysis was performed on 1003 cycles undergoing frozen-thawed, cleavage-stage embryo transfers from January 1, 2012 to June 31, 2015 in the Reproductive Medicine Center of Wuhan General Hospital of Guangzhou Military Region. Based on the infertility etiologies of the patients, the 1003 cycles were divided into five groups: tubal infertility, polycystic ovary syndrome (PCOS), endometriosis, male infertility, and unexplained infertility. The main outcome was the live birth rate. Two groups were set up based on the intervention: group A was given a GnRH agonist with exogenous estrogen and progesterone, and group B (control group) was given exogenous estrogen and progesterone only. The results showed that the baseline serum hormone levels and basic characteristics of the patients were not significantly different between groups A and B. The live birth rates in groups A and B were 41.67% and 29.29%, respectively (P〈0.05). The live birth rates in patients with PCOS in groups A and B were 56.25% and 30.61%, respectively (P〈0.05). The clinical pregnancy, implantation and on-going pregnancy rates showed the same trends as the live birth rates between groups A and B. The ectopic pregnancy rate was significantly lower in group A than in group B. We concluded that the live birth rate was higher and other clinical outcomes were more satisfactory with GnRH agonist co- treatment than without GnRH agonist co-treatment for frozen-thawed embryo transfer. The GnRH agonist combined with exogenous estrogen and progesterone worked for all types of infertility tested, especially for women with PCOS.展开更多
Objective To investigate the outcome of revised super-long down-regulation protocol (RSDP) for in vitro fertilization / intracytoplasmic sperm injection-embryo transfer (1VF/1CS1-ET) in the special infertile pat...Objective To investigate the outcome of revised super-long down-regulation protocol (RSDP) for in vitro fertilization / intracytoplasmic sperm injection-embryo transfer (1VF/1CS1-ET) in the special infertile patients with repeated implantation failure (RIF). Methods Patients with RIF were divided into RSDP group and routine long downregulation protocol (RLDP) group. In RSDP group, gonadotropin releasing hormone agonist (GnRHa) was injected intramuscularly by 2.5 mg in mid-luteal phase for the ftrst time and 1.25 mg after 28 d; gonadotropin (Gn) was started 14 d later after the second GnRHa dose. IVF/ICSI-ET was performed according to the routine procedure. The clinical outcomes of RSDP group were compared with those of RLDP group. Results In RSDP group, the number of retrieved oocytes and valid embryos was significantly lower (P〈0.05); there were no significant differences about fertilization rate (P〉0. 05); both good-quality embryo rate and implantation rate were significantly increased (P〈0. 005); clinical pregnancy rate was obviously improved (P〈0. 05), as compared with RLDP group.Conclusion RSDP can improve the IVF outcomes significantly in RIF patients.展开更多
Twenty-four-month-old male C57BU6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function a...Twenty-four-month-old male C57BU6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (STAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3βHSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of STAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (STAR, P450scc, and 3β-HSD) and the following promotion of testosterone syothesis in vivo.展开更多
文摘Sperm banking can preserve male fertility effectively, but the current conditions of sperm cryopreservation in China have not been investigated. This retrospective investigation was based on data collected at multiple centres in China from January 2003 to December 2008. The collected data included urogenital history, indication for cryopreservation, semen parameters, use rate, type of assisted reproductive technique (ART) treatment and pregnancy outcome. The study population included 1 548 males who had banked their semen during the study period at one of the clinics indicated above. Approximately 1.9% (30/1 548) of the cryopreserved semen samples were collected from cancer patients; about 88.8% (1 374/1 548) of the patients had banked their semen for ART and 8.6% (134/1 548) had a male infertility disease (such as anejaculation, severe oligozoospermia and obstructive azoospermia). The total use rate of cryopreserved semen was 22.7% (352/1 548), with 119 live births. The cancer group use rate was 6.7% (2/30), with one live birth by intracytoplasmic single sperm injection (ICSI). The ART group use rate was 23.2% (319/1 374), with 106 live births. The reproductive disease group use rate was 23.1% (31/134), with 12 live births. The semen parameters in each category varied; the cancer patient and infertility disease groups had poor semen quality. In vitro fertilization (IVF) and ICSI were the most common ART treatments for cryopreserved sperm. Semen cryopreservation as a salvage method is effective, but in many conditions it is underutilized, especially in cancer patients. Lack of awareness, urgency of cancer treatment and financial constraints are the main causes of the low access rate. The concept of fertility preservation should be popularized to make better use of this medical service in China.
文摘Environmental contaminants such as persistent organic pollutants (POPs) are man-made bioaccumulative compounds with long half-lives that are found throughout the world as a result of heavy use in a variety of consumer products during the twentieth century. Wildlife and animal studies have long suggested adverse effects of exposure to these compounds on human reproductive health, which, according to the endocrine disrupter hypothesis, are ascribed to the compounds' potential to interfere with endocrine signaling, especially when exposure occurs during certain phases of fetal and childhood development. An extensive number of epidemiological studies have addressed the possible effects of exposure to POPs on male reproductive health, but the results are conflicting. Thus far, most studies have focused on investigating exposure and the different reproductive health outcomes during adulthood. Some studies have addressed the potential harmful effects of fetal exposure with respect to malformations at birth and/ or reproductive development, whereas only a few studies have been able to evaluate whether intrauterine exposure to POPs has long-term consequences for male reproductive health with measurable effects on semen quality markers and reproductive hormone levels in adulthood. Humans are not exposed to a single compound at a time, but rather, to a variety of different substances with potential divergent hormonal effects. Hence, how to best analyze epidemiological data on combined exposures remains a significant challenge. This review on POPs will focus on current knowledge regarding the potential effects of exposure to POPs during fetal and childhood life and during adulthood on male reproductive health, including a critical revision of the endocrine disruption hypothesis, a comment on pubertal development as part of reproductive development and a comment on how to account for combined exposures in epidemiological research.
文摘Several animal studies indicate that mercury is a male reproductive toxicant, but human studies are few and contradictory. We examined semen characteristics and serum levels of reproductive hormones in relation to environmental exposure to mercury. Blood and semen samples were collected from 529 male partners of pregnant women living in Greenland, Poland and Ukraine between May 2002 and February 2004. The median concentration of the total content of mercury in whole blood was 9.2 ng ml-1 in Greenland (0.2- 385.8 ng ml-1), 1.0 ng m1-1 in Poland (0.2-6.4 ng ml-z) and 1.0 ng ml-I in Ukraine (0.2-4.9 ng ml-1). We found a significantly positive association between the blood levels of mercury and serum concentration of inhibin B in men from Greenland (p=0.074, 95% confidence interval (CI)=0.021 to 0.126) and in an analysis including men from all three regions (p=0.067, 95% C1=0.024 to O. 110). The association may be due to beneficial effects of polyunsaturated fatty acids (PUFAs), which are contained in seafood and fish. No significant association (P〉O.05) was found between blood concentrations of mercury and any of the other measured semen characteristics (semen volume, total sperm count, sperm concentration, morphology and motility) and reproductive hormones (free androgen index {FAI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and LH xtestosterone) in any region. In conclusion, the findings do not provide evidence that environmental mercury exposure in Greenlandic and European men with median whole blood concentration up to 10 ng m1^-1 has adverse effects on biomarkers of male reproductive health.
文摘Objective To report the first Bahrain national registry for ART treatments initiated from January 1, 2000 to December 31, 2005. Methods The "World Report on ART" forms, prepared by the International Committee for Monitoring Assisted Reproductive Technology (ICMART), were filled from database records of all procedures and their respective outcome carried out at Banoon ART Centre, the Military Hospital, Bahrain during the period of 2000-2006. Results A total of 1490 completed cycles were performed. ICSI constituted 42.68% (636), IVF constituted 35.50% (529), while frozen-thawed embryo replacement cycles represented only 21.18% (325) of all ART cycles. The clinical pregnancy rates per transfer for IVF and ICSI cycles were 26.65% and 21.70%, respectively. The distribution of singleton, twin and triplet deliveries for IVF,, ICSI and FET combined were 80. 0%, 16.3% and 3.7%, respectively. The average delivery rate per clinical pregnancy for fresh and frozen cycles was 57.3%. As a result of ART services, 266 neonates were born. Complications of ART were solely due to ovarian hyperstimulation syndrome (OHSS) which constituted 2.26% of all aspirated cycles. Conclusion Multiple pregnancy rate was high due to transferring 〉3 embryos. Pregnancy loss and OHSS were relatively high thus preventative measures were recommended. This report paves the way for the other IVF centers in Bahrain to provide their own data for the national ART registry.
基金from NHC Key Laboratory of Family Planning and Healthy/key laboratory of reproductive medicine of Hebei provincial(SZ-202006)Peking University International Hospital Research Funds(No.YN2019QN13).
文摘Melatonin,as a ubiquitous indoleamine hormone,is synthesized primarily by the pineal gland.It has diverse biological effects through quite complex mechanisms.More recently,studies have focused on the mechanism of melatonin in anti-reproductive toxicity/damage.Since melatonin possesses strong antioxidant and anti-apoptotic properties,researchers have examined its potential role in protecting against male reproductive toxicity/damage,which may be induced by chemotherapy or environmental toxicants and can lead to male infertility.In this article,recent progress regarding the protective effects of melatonin on male reproductive toxicity/damage is reviewed.
文摘As genetic factors can hardly explain the changes taking place during short time spans, environmental and lifestyle-related factors have been suggested as the causes of time-related deterioration of male reproductive function. However, considering the strong heterogeneity of male fecundity between and within populations, genetic variants might be important determinants of the individual susceptibility to the adverse effects of environment or lifestyle. Although the possible mechanisms of such interplay in relation to the reproductive system are largely unknown, some recent studies have indicated that specific genotypes may confer a larger risk of male reproductive disorders following certain exposures. This paper presents a critical review of animal and human evidence on how genes may modify environmental effects on male reproductive function. Some examples have been found that support this mechanism, but the number of studies is still limited. This type of interaction studies may improve our understanding of normal physiology and help us to identify the risk factors to male reproductive malfunction. We also shortly discuss other aspects of gene-environment interaction specifically associated with the issue of reproduction, namely environmental and lifestyle factors as the cause of sperm DNA damage. It remains to be investigated to what extent such genetic changes, by natural conception or through the use of assisted reproductive techniques, are transmitted to the next generation, thereby causing increased morbidity in the offspring.
文摘Objective To evaluate the risk of birth defects in children born following assisted reproductive technology (ART) and spontaneous conceptions. Methods This study carried out an updated systematic review to identify papers published by August 2013 with data relating to birth defects of children conceived using ART (IVF and for ICSI) compared with those spontaneously conceived and also compared birth defects between subgroups of lVF and ICSI. Results Totally 76 studies were identified for review. The individual relative risk (RR) estimated for these studies ranged from 0.44 to 5.51, a signifieantly increased risk of birth defects was observed (RR=l.36, 95%CI=1.25-1.47) in ART compared with the spontaneously conceived group, which was also evident in the subgroup analysis. Among these studies, 16 studies simultaneously gave data of birth defects comparing IVF and ICSI children, which showed no difference in risk of combined effects (RR=0.90, 95%CI=0.80 1.02), but ICSI had a higher risk in subgroups of clinical research (RR=O. 76, 95%CI=0.65-0.89) and crude RR value (RR=O. 78, 95%CI=0.67 0.91). Conclusion Pooled results from all suitable published studies suggested that children born following ART were at increased risk of birth defects compared with spontaneous conceptions. There is no difference in birth defect risk between children conceived by IVF or 1CS1 using a summative analysis, however, 1CS1 had a significant higher risk in birth defect risk comparing with 1VF when using subgroup analyses of sample size and RR value.
文摘Lessons from the occupational arena fdemonstrate the potential of industrial 4chemicals to damage human testicular function. An important but still unresolved question is whether low-level xenobiotic exposure of the general population poses a hazard. In this volume of the Asian Journal of Andrology, this issue is addressed by a series of reviews on xenobiotic exposure profiles, possible biological mechanisms, research methods and knowledge on impact of specific exposures. Interdisciplinary research fields as gene-environment interaction and male-mediated developmental toxicity is also addressed. Papers are cross-linked by answers to questions mutually put forward by the authors.
文摘The cell cycle is a tightly coupled series of events that enable cells to grow and proliferate.Cyclin-dependent kinases(CDKs)play crucial roles in the cell cycle by enabling cells to transition between different phases when they are activated.Cell cycle proteins enhance the activity of CDKs,while natural CDK inhibitors(CDKIs)suppress them.The cell cycle continues in cycles under normal conditions,but when conditions change,cells halt or terminate the cell cycle.Tumors are tissues that grow out of control,and the mechanisms of various types of tumors are different;however,almost all tumor cells share several common characteristics,including proliferation,prevention of apoptosis and genomic instability.Cellular division is essential in the progression of cancer.A key characteristic of cancer is the uncontrolled growth of tumor cells,which is due to the erratic behavior of several proteins during the cell cycle.Therefore,cell cycle regulators are considered attractive targets for the treatment of cancer.The present analysis highlights proteins that play a direct role in controlling the tumor cell cycle,such as CDKs,and provides a brief overview of checkpoint kinases.The present review also discusses how cell cycle proteins contribute to cancer and describes some of the antitumor drugs that are being researched.
文摘Selecting the embryo with the highest implantation potential is a top priority in in-vitro fertilization(IVF)centers.Few studies have explored the relationship between day 5 blastocyst morphokinetics and implantation outcomes[1].Despite numerous time-lapse studies,the findings often conflict due to differences in patient demographics,lab conditions,and protocols,such as oxygen concentration[2].Thus,there is ongoing debate regarding which parameters are most predictive of implantation.
文摘Diagnosis of male infertility has mainly been based on the World Health Organization (WHO) manual-based semen parameter's concentration, motility and morphology. It has, however, become apparent that none of these parameters are reliable markers for evaluation of the fertility potential of a couple. A search for better markers has led to an increased focus on sperm chromatin integrity testing in fertility work-up and assisted reproductive techniques. During the last couple of decades, numerous sperm DNA integrity tests have been developed. These are claimed to be characterized by a lower intraindividual variation, less intralaboratory and interlaboratory variation and thus less subjective than the conventional sperm analysis. However, not all the sperm chromatin integrity tests have yet been shown to be of clinical value. So far, the test that has been found to have the most stable clinical threshold values in relation to fertility is the sperm chromatin structure assay (SCSA), a flow cytometric test that measures the susceptibility of sperm DNA to acid-induced DNA denaturation in situ. Sperm DNA fragmentation as measured by SCSA has shown to be an independent predictor of successful pregnancy in first pregnancy planners as well as in couples undergoing intrauterine insemination, and can be used as a tool in investigation, counseling and treatment of involuntary childlessness. More conflicting data exist regarding the role of sperm DNA fragmentation in relation to fertilization, pre-embryo development and pregnancy outcome in in vitro fertilization and intracytoplasmic sperm injection (ICSI).
文摘Aim: To investigate the prevalence of high levels of sperm DNA damage among men from infertile couples with both normal and abnormal standard semen parameters. Methods: A total of 350 men from infertile couples were assessed. Standard semen analysis and sperm chromatin structure assay (SCSA) were carried out. Results: Ninety-seven men (28% of the whole study group) had a DNA fragmentation index (DFI) 〉 20%, and 43 men (12%) had a DFI 〉 30%. In the group of men with abnormal semen parameters (n = 224), 35% had a DFI 〉 20%, and 16% had a DFI 〉 30%, whereas these numbers were 15% and 5%, respectively, in the group of men with normal semen parameters (n = 126). Men with low sperm motility and abnormal morphology had significantly higher odds ratios (ORs) for having a DFI 〉 20% (4.0 for motility and 1.9 for morphology) and DFI 〉 30% (6.2 for motility and 2.8 for morphology) compared with men with normal sperm motility and morphology. Conclusion: In almost one-third of unselected men from infertile couples, the DFI exceeded the level of 20% above which, according to previous studies, the in vivo fertility is reduced. A significant proportion of men with otherwise normal semen parameters also had high sperm DNA damage levels. Thus, the SCSA test could add to explaining causes of infertility in cases where semen analysis has not shown any deviation from the norm. We also recommend running the SCSA test to choose the appropriate assisted reproductive technique (ART).
文摘It is well-documented that male overweight and obesity causes endocrine disorders that might diminish the male reproductive capacity; however, reports have been conflicting regarding the influence of male body mass index (BMI) on semen quality and the outcome of assisted reproductive technology (ART). The aim of this study was to investigate whether increased male BMI affects sperm quality and the outcome of assisted reproduction in couples with an overweight or obese man and a non-obese partner. Data was prospectively collected from 612 infertile couples undergoing ART at a Danish fertility center. Self-reported information on paternal height and weight were recorded and BMI was calculated. The men were divided into four BMI categories: underweight BMI 〈 20 kgm^-2, normal BMI 20-24.9 kg m^-2, overweight BMI 25-29.9 kgm^-2 and obese BMI 〉 30 kgm^-2. Conventional semen analysis was performed according to the World Health Organization guideline and sperm DNA integrity was analyzed by the Sperm Chromatin Structure Assay (SCSA). No statistically significant effect of male BMI was seen on conventional semen parameters (sperm concentration, total sperm count, seminal volume and motility) or on SCSA-results. Furthermore, the outcome of ART regarding fertilization rate, number of good quality embryos (GQE), implantation and pregnancy outcome was not influenced by the increasing male BMIo
文摘Male reproductive function is impaired during end-stage renal disease (ESRD). Disturbance of the hypothalamic-pituitary-gonadal axis, and therefore the regulation of sex hormones, is one of the major causes. Our focus was to include antimLillerian hormone (AMH) and inhibin B concentrations. Twenty male patients on hemodialysis, median age 40 (26-48) years, were analyzed for follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, sex hormone-binding globulin (SHBG), testosterone, estradiol, AMH and inhibin B levels. We used 144 proven fertile men, median age 32 (19-44) years as a control group and analyzed differences using multiple linear regression. Males with ESRD demonstrated higher mean values for prolactin, 742 versus normal 210 mlE 1-1 (95% confidence interval (Cl): 60.3, 729), LH, 8.87 versus normal 4.5 IE 1-1 (95% Ch 2.75, 6.14), and estradiol 89.7 versus normal 79.0 pmol 1-1 (95% CI: -1.31, -0.15). Mean value for AMH was lower, 19.5 versus normal 47.3 pmol 1-1 (95% Cl. -37.6, -11.6). There were no differences found for FSH, SHBG, inhibin B and testosterone. The most important difference was found for AMH, a marker of Sertoli cell function in the testes, which decreased by close to 60% when compared with controls. Combined with an increase in LH, these findings may indicate a dysfunction of Sertoli cells and an effect on Leydig cells contributing to a potential mechanism of reproductive dysfunction in men with ESRD.
基金This study was supported by the National Natural Science Foundation of China(No.81571489,No.81671834,No.81671449 and No.81871110)the Frontier and Key Technology Innovation Special Foundation of Guangdong Province,China(No.2016B030230001)+3 种基金the Natural Science Foundation of Guangdong Province,China(No.2014A030310359,No.2016A030313229 and No.2015A030313013)the Science and Technology Planning Project of Guangdong Province,China(No.2016A020214004)the Health Care Collaborative Innovation Foundation Major Projects of Guangzhou City,Guangdong Province,China(No.201604020189)the Youth Teacher Training Project of Sun Yat-sen University(No.17ykpy68 and No.18ykpy09).
文摘An ideal animal model of azoospermia would be a powerful tool for the evaluation of spermatogonial stem cell(SSC)transplantation.Busulfan has been commonly used to develop such a model,but 30%–87%of mice die when administered an intraperitoneal injection of 40 mg kg^?1.In the present study,hematoxylin and eosin staining,Western blot,immunofluorescence,and quantitative real-time polymerase chain reaction were used to test the effects of busulfan exposure in a mouse model that received two intraperitoneal injections of busulfan at a 3-h interval at different doses(20,30,and 40 mg kg^?1)on day 36 or a dose of 40 mg kg^?1 at different time points(0,9,18,27,36,and 63 days).The survival rate of the mice was 100%.When the mice were treated with 40 mg kg^?1 busulfan,dramatic SSC depletion occurred 18 days later and all of the germ cells were cleared by day 36.In addition,the gene expressions of glial cell line-derived neurotrophic factor(GDNF),fibroblast growth factor 2(FGF2),chemokine(C-X-C Motif)ligand 12(CXCL12),and colony-stimulating factor 1(CSF1)were moderately increased by day 36.A 63-day,long-term observation showed the rare restoration of endogenous germ cells in the testes,suggesting that the potential period for SSC transplantation was between day 36 and day 63.Our results demonstrate that the administration of two intraperitoneal injections of busulfan(40 mg kg^?1 in total)at a 3-h interval to mice provided a nonlethal and efficient method for recipient preparation in SSC transplantation and could improve treatments for infertility and the understanding of chemotherapy-induced gonadotoxicity.
基金the National Natural Science Foundation of China,No.81971759.
文摘Diabetic erectile dysfunction(DED)is a common complication of diabetes mellitus,significantly impairing the quality of life of patients.The conventional clinical treatment still has limitations.Stem cells(SCs),as a type of cells with multidirectional or directional differentiation capability and sustainable selfrenewal potential,are widely used in regenerative medicine and tissue engineering.With the continuous update of regenerative medicine theory and the success of animal experiments,SCs as a treatment for male erectile dysfunction,especially DED,have attracted widespread attention because of curable possibility.This review focus on the current progress in the clinical application of SC treatment for DED.Moreover,we summarize the development prospects of SCs in the field of DMED therapy.
基金supported by grants from the National Natural Science Foundation of China(No.81100401 and No.81470063)Guangdong Natural Science Foundation of China(No.2014A030313129)the Doctoral Fund of the Ministry of Education of China(No.20110171120096)
文摘Long-term gonadotropin-releasing hormone agonist(Gn RHa) administration before in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI) in infertile women with endometriosis or adenomyosis significantly enhanced the chances of pregnancy in both fresh and frozen embryo transfer cycles. We hypothesized that long-term Gn RHa treatment might also be beneficial for the idiopathic repeated implantation failure(RIF) patients. In the 21 patients receiving Gn RHa and hormone replacement therapy(G-HRT) protocols for frozen embryo transfer, their data were compared with those of the 56 of frozen/fresh cycles they had previously undergone(previous protocols). Comparison showed that the finial results were significantly better with G-HRT protocols than with their previous protocols, with pregnancy rate, clinical pregnancy rate, implantation rate and on-going pregnancy rate being 70%, 60%, 40% and 38% respectively with G-HRT protocols, against 17%, 11%, 6.3% and 5% with previous protocols. The results showed that hormonally controlled endometrial preparation with prior Gn RHa suppression could be used for patients who had experienced repeated failures of IVF treatment despite having morphologically optimal embryos, and the treatment may help increase the receptivity of the endometrium in these patients.
文摘The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone (GnRH) agonist were assessed. A retrospective cohort analysis was performed on 1003 cycles undergoing frozen-thawed, cleavage-stage embryo transfers from January 1, 2012 to June 31, 2015 in the Reproductive Medicine Center of Wuhan General Hospital of Guangzhou Military Region. Based on the infertility etiologies of the patients, the 1003 cycles were divided into five groups: tubal infertility, polycystic ovary syndrome (PCOS), endometriosis, male infertility, and unexplained infertility. The main outcome was the live birth rate. Two groups were set up based on the intervention: group A was given a GnRH agonist with exogenous estrogen and progesterone, and group B (control group) was given exogenous estrogen and progesterone only. The results showed that the baseline serum hormone levels and basic characteristics of the patients were not significantly different between groups A and B. The live birth rates in groups A and B were 41.67% and 29.29%, respectively (P〈0.05). The live birth rates in patients with PCOS in groups A and B were 56.25% and 30.61%, respectively (P〈0.05). The clinical pregnancy, implantation and on-going pregnancy rates showed the same trends as the live birth rates between groups A and B. The ectopic pregnancy rate was significantly lower in group A than in group B. We concluded that the live birth rate was higher and other clinical outcomes were more satisfactory with GnRH agonist co- treatment than without GnRH agonist co-treatment for frozen-thawed embryo transfer. The GnRH agonist combined with exogenous estrogen and progesterone worked for all types of infertility tested, especially for women with PCOS.
文摘Objective To investigate the outcome of revised super-long down-regulation protocol (RSDP) for in vitro fertilization / intracytoplasmic sperm injection-embryo transfer (1VF/1CS1-ET) in the special infertile patients with repeated implantation failure (RIF). Methods Patients with RIF were divided into RSDP group and routine long downregulation protocol (RLDP) group. In RSDP group, gonadotropin releasing hormone agonist (GnRHa) was injected intramuscularly by 2.5 mg in mid-luteal phase for the ftrst time and 1.25 mg after 28 d; gonadotropin (Gn) was started 14 d later after the second GnRHa dose. IVF/ICSI-ET was performed according to the routine procedure. The clinical outcomes of RSDP group were compared with those of RLDP group. Results In RSDP group, the number of retrieved oocytes and valid embryos was significantly lower (P〈0.05); there were no significant differences about fertilization rate (P〉0. 05); both good-quality embryo rate and implantation rate were significantly increased (P〈0. 005); clinical pregnancy rate was obviously improved (P〈0. 05), as compared with RLDP group.Conclusion RSDP can improve the IVF outcomes significantly in RIF patients.
基金This work was supported by the National Natural Science Foundation of China (No. 81302223) and the Medical Scientific Research Foundation of Guangdong Province, China (B2013104).
文摘Twenty-four-month-old male C57BU6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (STAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3βHSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of STAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (STAR, P450scc, and 3β-HSD) and the following promotion of testosterone syothesis in vivo.