Male infertility: lifestyle factors and holistic, complementary, and alternative therapies

Hydroxycitric acid and capsaicin combination alleviates obesity-induced testicular apoptosis, oxidative stress and inflammation

Recent research in rodents suggests that oxidative stress, inflammation, and apoptosis in the testes caused by high-fat diets (HFD) are a cause of male infertility. To investigate the therapeutic efficacy of the combination of hydroxycitric acid and capsaicin (HCC) against male reproductive disorders, we developed an HFD-induced obese rat model. Rats received HFD supplementation for 21 weeks, which induced obesity. From week 16, HCC (100 mg/kg body weight) was administered to investigate its potential to treat testicular toxicity. According to the results of the current study, treatment of obese rats with HCC improved their sperm quality, increased the production of testosterone, follicle-stimulating hormone, and luteinizing hormone and significantly increased the activities of steroidogenic enzymes and corresponding mRNA levels. In addition, HCC decreased lipid peroxidation and nitric oxide levels in both spermatozoa and testes while increasing the expression of mRNA for the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase in the testes, which in turn reduced oxidative stress in the testes. Moreover, after HCC treatment, testicular tissues showed a remarkable decrease in mRNA levels responsible for inflammation (TNF-α, IL-6, NF-κB) and apoptosis (Bax and Bcl-2). Our results suggest that HCC may alleviate obesity-induced male reproductive dysfunction by attenuating oxidative stress, inflammation, and apoptosis in the testes of HFD-induced obese male rats.

Oxidative Stress-Associated Male Infertility: Current Diagnostic and Therapeutic Approaches

Infertility is a prevalent global issue affecting approximately 17.5% of adults, with sole male factor contributing to 20-30% of cases. Oxidative stress (OS) is a critical factor in male infertility, disrupting the balance between reactive oxygen species (ROS) and antioxidants. This imbalance detrimentally affects sperm function and viability, ultimately impairing fertility. OS also triggers molecular changes in sperm, including DNA damage, lipid peroxidation, and alterations in protein expression, further compromising sperm functionality and potential fertilization. Diagnostic tools discussed in this review offer insights into OS markers, antioxidant levels, and intracellular ROS concentrations. By accurately assessing these parameters, clinicians can diagnose male infertility more effectively and thus tailor treatment plans to individual patients. Additionally, this review explores various treatment options for males with OS-associated infertility, such as empirical drugs, antioxidants, nanoantioxidants, and lifestyle modifications. By addressing the root causes of male infertility and implementing targeted interventions, clinicians can optimize treatment outcomes and enhance the chances of conception for couples struggling with infertility.

Effect of alternative and complementary medicine on male infertility: An umbrella review

Background and Aims

There is increasing interest worldwide in using alternative and complementary approaches for treating male infertility. This interest has spawned a multitude of published systematic reviews and meta-analyses. The aim of this Umbrella review was to consolidate the available evidence regarding the effect of complementary and alternative medicine on male infertility to inform clinical decision-making processes.

Methods

A comprehensive search was conducted to identify systematic reviews and meta-analyses pertaining to the effects of complementary and alternative medicine on male infertility. This search encompassed various databases including MEDLINE, CINAHL, PubMed, Scopus, Proquest, Google Scholar, SID, EMBASE, Magiran, Cochrane Library, Iranmedex, ScienceDirect, SAGE. Subsequently, two researchers independently extracted the data from the selected meta-analyses and systematic reviews, and evaluated their methodological quality using the assessment of multiple systematic reviews 2 (AMSTAR2).

Results

This analysis encompassed 11 studies, with four originating from Iran, two from Korea and five from China. The results regarding the effectiveness of complementary and alternative medicine are controversial, indicating a need for further research. The methodological quality of the systematic reviews and meta-analyses appraised by AMSTAR 2 was rated as low or critically low. This assessment is attributed to inadequate examination of publication biases in the reviews and a lack of discussion regarding the effect of risk of bias.

Conclusion

The existing evidence regarding the effectiveness of alternative and complementary medicine in addressing male infertility is limited. Furthermore, the overall methodological quality of the published systematic reviews and meta-analyses may have been underestimated as the use of AMSTAR2 appears to be a more precise appraisal instrument compared to its predecessor.

Articles in the field of infertility (2013-2022): a bibliometric analysis

To carry out an in-depth analysis of the scientific research on infertility, we performed the first bibliometric analysis focusing on studies involving global literature on infertility during the period 2013-2022. Analysis of 33239 articles in the field of infertility showed a significant increasing trend in the number of publications over the period 2013-2022, with authors mainly from the USA and China. Shanghai Jiao Tong University published the most articles. This study is the first to analyze the global field of infertility (2013-2022) from multiple indicators by bibliometrics, thus providing new insights into the research hotspots and development trends in the field of infertility.

Are epigenetic mechanisms and nutrition effective in male and female infertility?

This review discusses epigenetic mechanisms and the relationship of infertility in men and women in relation to parameters pertaining to nutrition. The prevalence of infertility worldwide is 8-12 %, and one out of every eight couples receives medical treatment. Epigenetic mechanisms, aging, environmental factors, dietary energy and nutrients and non-nutrient compounds; more or less energy intake, and methionine come into play in the occurrence of infertility. It also interacts with vitamins B12, D and B6, biotin, choline, selenium, zinc, folic acid, resveratrol, quercetin and similar factors. To understand the molecular mechanisms regulating the expression of genes that affect infertility, the environment, the role of genotype, age, health, nutrition and changes in the individual's epigenotype must first be considered. This will pave the way for the identification of the unknown causes of infertility. Insufficient or excessive intake of energy and certain macro and micronutrients may contribute to the occurrence of infertility as well. In addition, it is reported that 5-10 % of body weight loss, moderate physical activity and nutritional interventions for improvement in insulin sensitivity contribute to the development of fertility. Processes that pertain to epigenetics carry alterations which are inherited yet not encoded via the DNA sequence. Nutrition is believed to have an impact over the epigenetic mechanisms which are effective in the pathogenesis of several diseases like infertility. Epigenetic mechanisms of individuals with infertility are different from healthy individuals. Infertility is associated with epigenetic mechanisms, nutrients, bioactive components and numerous other factors.

Riboflavin compounds show NAD(P)H dependent quinone oxidoreductase-like quinone reducing activity

NAD(P)H-dependent quinone oxidoreductase (NQO) is an essential enzyme in living organisms and cells protecting them from oxidative stress. NQO reduces coenzyme Q (CoQ) using NAD(P)H as an electron donor. In the present study, we searched for coenzyme Q10 reducing activity from fractions of gel filtration-fractionated rat liver homogenate. In addition to the large-molecular-weight fraction containing NQO, CoQ10 reducing activity was also detected in a low-molecular-weight fraction. Furthermore, dicumarol, a conventional inhibitor of NQO1 (DT diaphorase), did not inhibit the reduction but quercetin did, suggesting that the activity was not due to NQO1. After further purification, the NADH-dependent CoQ10-reducing compound was identified as riboflavin. Riboflavin is an active substituent of other flavin compounds such as FAD and FMN. These flavin compounds also reduced not only CoQ homologues but also vitamin K homologues in the presence of NADH. The mechanism was speculated to work as follows: NADH reduces flavin compounds to the corresponding reduced forms, and subsequently, the reduced flavin compounds immediately reduce bio-quinones. Furthermore, the flavin-NADH system reduces CoQ10 bound with saposin B, which is believed to function as a CoQ transfer protein in vivo. This flavin-dependent CoQ10 reduction, therefore, may function in aqueous phases such as the cell cytosol and bodily fluids.

The Effects of Glutathione on Clinically Essential Fertility Parameters in a Bleomycin Etoposide Cisplatin Chemotherapy Model

Chemotherapeutic agents used in the treatment of testicular cancer cause damage to healthy tissues, including the testis. We investigated the effects of glutathione on sperm DNA integrity and testicular histomorphology in bleomycin etoposide cisplatin (BEP) treated rats. Twelve-week-old male rats of reproductive age (n = 24) were randomly divided into three groups, the (i) control group, (ii) BEP group, and (iii) BEP+ glutathione group. Weight gain increase and testes indices of the control group were found to be higher than that of the BEP group and BEP+ glutathione group. While the BEP treatment increased sperm DNA fragmentation and morphological abnormalities when compared to the control group, GSH treatment resulted in a marked decrease for both parameters. Moreover, BEP treatment significantly decreased serum testosterone levels and sperm counts in comparison to the control group, yet this reduction was recovered in the BEP+ glutathione treated group. Similarly, seminiferous tubule epithelial thicknesses and Johnsen scores in testicles were higher in the control and BEP+ glutathione groups than in the BEP-treated group. In conclusion, exogenous glutathione might prevent the deterioration of male reproductive functions by alleviating the detrimental effects of BEP treatment on sperm quality and testicular histomorphology.

Vitamin D supplementation for improving sperm parameters in infertile men: A systematic review and meta-analysis of randomized clinical trials

Objective

Vitamin D has been hypothesized to have a potential role in altering sperm motility and metabolism. However, experimental studies have demonstrated inconsistent results between vitamin D and sperm parameters. This study aims to investigate the role of vitamin D supplementation to improve sperm parameters in infertile men.

Methods

This is a systematic review and meta-analysis study. We comprehensively conducted a search on ClinicalTrials.gov, IRCT.ir, Europe PMC, and PubMed and collected published studies on vitamin D supplementation and sperm parameters for infertile men. The risk of bias was assessed by using Risk of Bias version 2 (RoB v2) and the statistical analysis was performed by using Review Manager 5.4 software.

Results

Five trials with a total of 648 infertile men were included. Our meta-analysis showed that supplementation with vitamin D may significantly improve total sperm motility [mean difference 4.96 (95% CI 0.38, 9.54), p = 0.03, I2 = 69%], progressive sperm motility [mean difference 4.14 (95% CI 0.25, 8.02), p = 0.04, I2 = 89%], and normal sperm morphology [mean difference 0.44 (95% CI 0.30, 0.57), p < 0.00001, I2 = 0%] better than placebo in infertile men. However, total sperm count (p = 0.15), sperm concentration (p = 0.82), and semen volume (p = 0.83) did not differ significantly between two groups.

Conclusions

Vitamin D supplementation may improve sperm motility, progressive sperm motility, and morphology in infertile men. Vitamin D supplementation may be considered in managing male fertility issue.

Gut microbiota involved in spermatogenic function of Sancai Lianmei granules in obese mice

Obesity is a well-established cause of reduced fertility and semen quality in men. Current evidence suggests that Sancai Lianmei granules (SCLM) effectively improve sexual function and semen quality in diabetic patients, while the gut microbiota can influence disease metabolism through various mechanisms. However, the effect of SCLM on the obesity-induced decrease in semen quality and on the gut microbiota is unclear. This study aimed to investigate the effects of SCLM on spermatogenic function and gut microbiota in obese mice. Obese mice were induced by a high-fat diet, and lipid metabolism, spermatogenic function, inflammatory factors, oxidative stress, and autophagy were analyzed to determine the effects of SCLM and SCLM-fecal microbiota transplantation (FMT). In addition, changes in the gut microbiota of mice were analyzed. SCLM and SCLM + FMT could effectively reduce the levels of total cholesterol (TC), high-density lipoprotein (HDL), and low-density lipoprotein (LDL); decrease the expression of oxidative stress products malondialdehyde (MDA) and 8-hydroxyde-oxyguanosine (8-OHdG); and increase sperm density and sperm viability in obese mice while inhibiting the inflammatory responses and excessive cellular autophagy, indicating that SCLM and SCLM + FMT exerted a protective effect on spermatogenic functions. Furthermore, SCLM affected the gut microbiota composition in mice. This study determined that obesity can lead to reduced sperm motility and affect the composition of the gut microbiota, while SCLM can regulate blood lipids in mice directly or indirectly by regulating gut microbiota changes, and may improve sperm motility in obese mice by reducing oxidative stress and autophagy. In addition, FMT enhanced this effect, which may be related to the diversity of gut microbiota.

Electroacupuncture Effectiveness for Treating Idiopathic Male Infertility

Background

Male infertility accounts for ∼50% of all infertility cases. The reasons for male infertility may vary, and one of them is related to an idiopathic factor that may impair spermatogenesis. Acupuncture is one of the most well-known and widely accepted alternative treatments and is becoming known as an effective complementary therapy for infertility.

Case

The case in this article demonstrated the effectiveness of electroacupuncture (EA) for improving male fertility by referring to the total motile sperm count (TMSC), sperm morphology and motility, DNA Fragmentation Index (DFI) of the sperm before and after EA, and pregnancy success in a couple with male infertility. Couples are given therapy with EA twice per week for up to 12 sessions and planned intercourse during the fertile period (ovulation). After planned intercourse, the wife became pregnant; an intrauterine gestational sac (GS) was seen on transvaginal ultrasound and her human chorionic gonadotropin urine test was positive.

Results

The TMSC parameter, sperm morphology and sperm motility, post-EA DFI was improved, compared to pre-EA. The couple was became pregnant after undergoing EA 12 times to treat male infertility.

Conclusions

This case illustrated that EA therapy for idiopathic male infertility has an effect toward improvement of the spermiogram test result, DFI, and success in achieving a pregnancy. However, further research is needed because there are many patients with different causes for their infertility.

Clinical study of Wuwei Fuzheng Yijing formula in the treatment of sperm DNA damage in male infertility: A study protocol for a randomized controlled trial

BACKGROUND

The incidence of male infertility is increasing in recent years, and the semen routine examination of some patients is normal, but the semen pathological examination shows that the sperm DNA fragmentation index (DFI) is high, and the patients' clinical manifestations are infertility or recurrent abortion of their spouses. At present, there is no special treatment for male infertility caused by high DFI, and traditional Chinese medicine compound prescription shows potential value in the treatment of male infertility. Wuwei Fuzheng Yijing formula (WFY) is an effective prescription for the treatment of sperm DNA damage in male infertility, but there is no strict clinical trial to support its application. Therefore, we designed a randomized controlled trial to evaluate the efficacy and safety of WFY in patients with sperm DNA damage in male infertility.

METHODS

In this randomized controlled study, 100 patients who met the inclusion criteria were randomly divided into WFY group and levocarnitine oral solution group. The treatment period was 12 weeks. The main observation index was sperm DFI, and the secondary observation index was sperm concentration, motility, survival rate, and TCM syndrome score. Safety observation indicators will include electrocardiogram, blood tests (including blood routine tests, liver and renal function), routine urine tests, and routine stool tests. All results were evaluated at the 4th and 8th week of the baseline, and the end of treatment.

DISCUSSION

This study will provide a basis for the efficacy and safety of WFY in the treatment of sperm DNA damage in male infertility with spleen and kidney qi deficiency and blood stasis.

Beneficial Effect of Methanolic Extract of Frankincense (Boswellia Sacra) on Testis Mediated through Suppression of Oxidative Stress and Apoptosis

Boswellia sacra oleo gum resin (Burseraceae) commonly known as frankincense is traditionally used in many countries for its beneficial effect on male fertility. This study explores its effect on the male reproductive system after a 60-day repeated administration at two different doses to rats (in vivo) and on human Leydig cells (in vitro). The methanolic extract of B. sacra was analyzed for the presence of various constituents by preliminary phytochemical analysis and gas chromatography-mass spectrometry (GC-MS) while quantitative analysis of boswellic acids was done by high-performance liquid chromatography (HPLC). Administration of B. sacra extract to rats elevated the serum testosterone levels with an associated reduction in serum levels of FSH and LH. An increase in the activity of antioxidant enzymes, superoxide dismutase and catalase, was seen. A dose-dependent increase in the sperm count and sperm motility was also observed. The in vivo results were supported by changes in the expression of the Bcl-2 gene and caspase-3 gene in human Leydig cells in vitro. The results of this study support the traditional use of B. sacra to increase male fertility.

The Potential Benefits of Legumes Germ and Cereal Grains on Roosters' Reproductive Performance

Vit E is known as one of the most important antioxidant. It has been previously approved that cereal grains and leafy plants are considered as the main source for α-tocopherol (Vit E). One of the recommended therapies for male infertility would be the Vit E therapy. Following Vit E consumption the semen parameters such as sperm concentration, ejaculation volume, sperm progressive motility, and in vitro function (zone binding assay) have been significantly improved. Therefore, present study was designed to investigate the effects of oral administration of cereal grain and seeds on reproductive performance of local cocks. During a period of 63 weeks, 100 local (Iraqi breed) rooster chicks were randomly divided into the five groups (n=20). Animals in group 1 served as control group and had not received any supplementations in their diet. The animals in the Groups 2-5 received diets which were fortified with 100, 200, 300, and 400 g of cereal grain and legume seeds pure germs. The results of the current study showed that the total number of spermatozoa and percentages of abnormal sperm were decreased by adding more amount of germ of cereal grain and seeds (P<0.01). Increased germ of cereal grain and seeds was not associated with pH volume, colour, consistency and motility of the sperm compared to corresponding rates in control group. Phospholipids content and thiobarbituric acid reactive substance of semen sample as well as density of ejaculate (sperm/µl) were decreased by adding increasing germ of cereal grain and seeds in diet of rosters. Weight of testis decreased by increasing levels of cereal grains and legume seeds germ in the diets (P<0.05).

A Systematic Review on Use of Medicinal Plants for Male Infertility Treatment

Objective: Male infertility is involved in about half of the casess of infertility and the only sole reason for infertility in 20%-30% of the cases. Following the recent interest in the use of medicinal plants, scientists have sought to clarify their effects on male fertility. This review aimed to summarize the results of studies available to determine the effectiveness, safety and mechanism of herbal treatments in the improvement of male fertility.

Materials and methods: Medline/PubMed, Scopus, Science Direct, and the Cochrane Central Register of Controlled Trials (Central) databases were searched for randomized controlled trials (RCTs) published during 2000-2020. Studies were only included if they adhered to the CONSORT checklist. The methodological quality of the selected studies was assessed using the Cochrane risk of bias tool.

Results: Finally, 20 studies recruiting a total of 1519 individuals were reviewed. These studies compared the effects of eleven different medicinal plants, i.e. ginseng, saffron, Nigella sativa, palm pollen, ADOFON, TOPALAF, sesame, and Mucuna pruriens, on male fertility with those of placebo. All studies (except one) confirmed the beneficial effects of medicinal plants on the improvement of sperm and reproductive parameters and thus male infertility.

Conclusion: The existing RCTs indicated the positive effects of medicinal plants on male fertility. Therefore, in order to develop a novel approach to the treatment of male infertility, further clinical trials are warranted to determine the maximum dosage and duration of treatment with herbal medicines and evaluate any potential side effects of such interventions.

Network Pharmacology-Based Strategy to Investigate Pharmacological Mechanisms of the Drug Pair Astragalus-Angelica for Treatment of Male Infertility

Background

The traditional Chinese medicines Astragalus and Angelica are often combined to treat male infertility, but the specific therapeutic mechanism is not clear. Therefore, this study applies a network pharmacology approach to investigate the possible mechanism of action of the drug pair Astragalus-Angelica (PAA) in the treatment of male infertility.

Methods

Relevant targets for PAA treatment of male infertility are obtained through databases. Protein-protein interactions (PPIs) are constructed through STRING database and screen core targets, and an enrichment analysis is conducted through the Metascape platform. Finally, molecular docking experiments were carried out to evaluate the affinity between the target protein and the ligand of PAA.

Results

The active ingredients of 112 PAA, 980 corresponding targets, and 374 effective targets of PAA for the treatment of male infertility were obtained, which are related to PI3K-Akt signaling pathway, HIF-1 signaling pathway, AGE-RAGE signaling pathway, IL-17 signaling pathway, and thyroid hormone signaling pathway.

Conclusion

In this study, using a network pharmacology method, we preliminarily analyzed the effective components and action targets of the PAA. We also explored the possible mechanism of action of PAA in treating male infertility. They also lay a foundation for expanding the clinical application of PAA and provide new ideas and directions for further research on the mechanisms of action of the PAA and its components for male infertility treatment.

The influence of a combination of lifestyle modification and a new formula supplement with antioxidative and antioestrogenic activity on mild idiopathic abnormalities of semen parameters-A pilot study

Unhealthy lifestyle and environmental factors may influence semen parameters via oxidative stress, functional hypogonadism and xenobiotics. The aim of the study was to evaluate the influence of a diet supplement containing glutathione and herbs with antioxidative and antioestrogenic activity, in combination with lifestyle improvement, on semen parameters. Data from the medical records of 50 men aged 24-52 (median 35.0) with idiopathic abnormalities in semen parameters were retrospectively analysed. The inclusion criteria comprised sperm concentration >5 mln/ml, disorders in sperm motility and/or vitality and/or morphology, good general health, no present nor previous diseases or treatment which may influence fertility, and normal testicular volume. Patients were advised to change their lifestyle and take the supplement for three months. Basic semen analysis and serum FSH, LH and testosterone levels were performed before and after the prescribed therapy. After three months of treatment, median serum concentrations of FSH significantly increased by 70%, LH by 67% and testosterone by 79%, and all mean semen parameters were significantly increased (total sperm count by 68%). It seems that lifestyle changes supported by consumption of herbs with antioxidative and antioestrogenic activity may be suitable for the first-line therapy for patients with mild idiopathic abnormalities in semen parameters or serum concentrations of reproductive hormones.

The factors affecting male infertility: A systematic review

Background

In recent years, the incidence of male infertility has increased worldwide. It is necessary to study the factors that influence male infertility in each area/region for better management.

Objective

To determine the factors affecting male infertility in the Iranian male population.

Materials and Methods

An online search was conducted in electronic databases including PubMed, Google Scholar, SID, and Scopus to identify articles on the factors associated with male infertility, published in English and Persian. The keywords used to perform the search included "factor", "epidemiology", "causes of infertility", and "male infertility". The search was conducted without a time restriction, up to April 2020.

Results

The search resulted in a total number of 691 studies. After an assessment of the articles, finally 14 studies were included in this study with a total number of 26,324 infertile males. The factors associated with male infertility included semen abnormalities, varicocele and testis disorder, smoking, exposure to heat, obesity, anabolic steroids, vascular abnormalities, anti-spermatogenesis factors, antidepressants, taking ranitidine and cimetidine, penile discharge and genital ulcers, painful micturition, occupational factors, alcohol, chronic disease, sexual disorder, Surgical and urological diseases, genetic factors and herpes infection. Among these, the semen and varicocele disorders were common in most studies.

Conclusion

The present review suggests that the factors affecting male infertility in Iran are similar to those reported from other countries. The results of this study can be used in adopting appropriate strategies for infertility management in Iran.

Stem cell therapy as a recent advanced approach in male infertility

Infertility is one of the most common problems in the world that has negative effects on society and infertile people. Among the various causes of infertility, male infertility accounts for almost half of all infertility cases. Despite advances in medicine, current male infertility treatments such as assisted reproductive technology (ART) have not been successful in treating all types of male infertility. Recently, stem cells have been considered as therapeutic targets for many diseases, including infertility, due to their self-renewing and high differentiation. The purpose of this review is to discuss different types of male infertility and the effect of various stem cells against the treatment of male infertility.

Male factor infertility: Initial workup and diagnosis in primary care

OBJECTIVE

To present a case-based discussion on the workup of male factor infertility and review currently available treatments.

SOURCES OF INFORMATION

This discussion is based on the current Canadian Urological Association and American Urological Association guidelines, with reference to landmark papers as appropriate from 2010 onward. All articles were retrieved through PubMed.

MAIN MESSAGE

Approximately 15% of Canadian couples experience infertility, making it a commonly encountered condition in the primary care setting. Among couples suffering from infertility, male factors can be identified as the sole cause in 30% of cases and as a contributing issue in 20% of cases. Although many of the treatments described aim to improve a couple's chances of naturally conceiving a child via intercourse, many patients ultimately require medical or surgical intervention to achieve pregnancy. This can be a long, protracted course for patients, with important roles for primary care providers and fertility specialists alike.

CONCLUSION

Male fertility assessment and treatment has historically been left in the hands of fertility specialists, creating a bottleneck for patients to receive fertility care. However, with increased understanding of the underlying causes of male factor infertility, the workup and initial management can occur in the primary care setting, helping to streamline care.

Acupuncture Therapy for Severe Oligoasthenoteratozoospermia

Background: Infertility affects ∼15%-20% of couples. Of the 16.7% infertility rate reported based on Word Health Organisation questionnaire data, 6.4% of cases are associated with male factors. Male infertility can result from abnormal semen parameters; oligoasthenoteratozoospermia (OAT) is the most common diagnosis. Acupuncture is an ancient method that has been used for centuries to treat and prevent various conditions. In modern medicine, it is gaining popularity as a complementary infertility therapy. Case: A 41-year-old male presented to the Medical Acupuncture Department of Dr. Cipto Mangunkusumo Hospital (in Jakarta, Indonesia) because he wanted to have a child. His semen was analyzed, and he was diagnosed with severe OAT. Manual acupuncture therapy was performed at CV 3, CV 4, CV 5, CV 6, CV 7, ST 29, SP 6, SP 3, ST 36, and KI 3, alternating with KI 7 5 days per week and at LR 8 once per week, for a total of 28 sessions. Results: Semen analysis after 2 series of manual acupuncture treatments revealed improvement, especially in sperm motility, from 25% to 33% and then to 67% after the first and second serial therapies, respectively, changing the diagnosis from severe OAT to severe oligoteratozoospermia. Conclusions: Manual acupuncture combined with medication improves male fertility, especially sperm motility.

The efficacy and safety of acupuncture in the treatment of erectile dysfunction: A protocol for systematic review and meta-analysis

BACKGROUND

Erectile dysfunction (ED) can negatively affect men's mental health, interpersonal relationships, and overall well-being. ED has affected >150 million men worldwide, and this number will reach approximately 322 million by 2025. Although PDE5-Is is a landmark in the treatment of erectile dysfunction, it may have side effects such as penile pain, cardiovascular dysfunction, and deafness. Some studies have shown that acupuncture may have a positive effect on the pathophysiology of ED. Therefore, we will select all randomized controlled trials related to evaluate the efficacy and safety of acupuncture treatment of ED.

METHODS

This study will systematically search 7 digital databases including China National Knowledge Infrastructure, Wanfang, VIP, China Biology Medicine, Cochrane Library, PubMed, and Embase for randomized controlled trials without language restrictions. Two researchers will independently read the title, abstract, and full text to screen for studies that can be included in the meta-analysis. If there is any dispute, the third party will be required to reach a consensus.

RESULTS

The purpose of this study is to evaluate the efficacy and safety of acupuncture in the treatment of ED and the difference in the impact of different types of acupuncture on ED.

CONCLUSION

Judge whether acupuncture and moxibustion can help improve the symptoms of ED by evaluating relevant literatures, and make up for the lack of relevant research.

INPLASY REGISTRATION NUMBER

INPLASY 202140040.

The quality of systematic reviews and meta-analyses assessing the treatment and management of male infertility

BACKGROUND

Male factor infertility (MFI) is a common medical condition which requires high-quality research to guide clinical practice; however, systematic reviews (SRs) and meta-analyses (MAs) often vary in quality, raising concerns regarding the validity of their results. We sought to perform an objective analysis of SRs and MAs in MFI treatment and management and to report on the quality of published literature.

METHODS

A comprehensive search in PubMed/MEDLINE and Embase was used to identify relevant publications. Primary search terms were male infertility, male sterility, and male subfertility. Two authors independently performed searches, screened citations for eligibility, extracted data for analysis, and graded methodological quality using the validated AMSTAR (A Measurement Tool to Assess Systematic Reviews) instrument, a validated tool used in the critical appraisal of SRs/MAs.

RESULTS

Of 27 publications met inclusion criteria and were included in the analysis. Mean AMSTAR score (± SD) among all publications was 7.4 (1.9) out of 11, reflecting "fair to good" quality. Non-pharmacological medical treatment for MFI was the most commonly assessed intervention (n = 13, 48.1%). No publications met all AMSTAR criteria. While the number of SRs/MAs has increased over time (P = 0.037), the quality of publications has not significantly changed (P = 0.72). SRs/MAs of the Cochrane Library had higher AMSTAR score than non-Cochrane SRs/MAs (8.5 vs 6.3, P = 0.002).

CONCLUSIONS

The methodological quality of SRs/MAs should be assessed to ensure high-quality evidence for clinical practice guidelines in MFI treatment and management. This review highlights a need for increased effort to publish high-quality studies in MFI treatment and management.

Advances on hormone-like activity of Panax ginseng and ginsenosides

Traditional Chinese medicine (TCM) has been paid much attentions due to the prevention and treatment of steroid hormone disorders. Ginseng, the root of Panax ginseng C. A. Meyer (Araliaceae), is one of the most valuable herbs in complementary and alternative medicines around the world. A series of dammarane triterpenoid saponins, also known as phytosteroids, were reported as the primary ingredients of Ginseng, and indicated broad spectral pharmacological actions, including anti-cancer, anti-inflammation and anti-fatigue. The skeletons of the dammarane triterpenoid aglycone are structurally similar to the steroid hormones. Both in vitro and in vivo studies showed that Ginseng and its active ingredients have beneficial hormone-like role in hormonal disorders. This review thus summarizes the structural similarities between hormones and dammarane ginsenosides and integrates the analogous effect of Ginseng and ginsenosides on prevention and treatment of hormonal disorders published in recent twenty years (1998-2018). The review may provide convenience for anticipate structure-function relationship between saponins structure and hormone-like effect.

Yishentongluo decoction in treatment of idiopathic asthenozoospermia infertility: Study protocol for a randomized controlled trial

BACKGROUND

The reproductive dilemma faced by men has always been the focus of the whole society. Idiopathic asthenozoospermia (AZS), as one of the common causes of male infertility, lack of specific treatment. Traditional Chinese medicine has shown potential benefits in the management of male infertility. Yishentongluo decoction (YSTL) is a representative Chinese herbal formula; however, there is still no rigorous clinical trial supporting its application. Therefore, we designed a randomized controlled trial to evaluate the efficacy and safety of YSTL for patients with idiopathic AZS and explain the possible action mechanisms of YSTL in improving sperm motility.

METHODS

In this randomized controlled study, a total of 160 eligible patients will be assigned to YSTL group or the Levocarnitine oral solution group in a 1:1 ratio. The treatment period will be 12 weeks and the follow-up period will last 4 weeks. The primary outcome will be the the progressive (motility), sperm rate (%). Secondary outcomes will include the progressive (motility) + non-progressive (motility) sperm rate(%), total effective sperm count, inner mitochondrial membrane potential (MMP) in spermatozoa, and spouse pregnancy rate (%). Safety outcomes will cover electrocardiogram , blood tests (including blood routine test, hepatic function, and renal function), urine routine test, and stool routine test. The semen parameters, sperm MMP test, and all the safety outcomes will be performed at the baseline, 4th, 8th and 12th week. The pregnancy outcome will be evaluated at 4 weeks after treatment.

DISCUSSION

This study will provide initial evidence regarding the efficacy and safety of YSTL in the treatment of idiopathic AZS with kidney deficiency and blood stasis pattern. In addition, potential mechanisms of YSTL in improving sperm motility will be explored based on sperm MMP test.

TRIAL REGISTRATION

Chinese Clinical Trials Register identifier, ChiCTR2000033290, registered on 26 May 2020.

Abnormal lipid metabolism induced apoptosis of spermatogenic cells by increasing testicular HSP60 protein expression

Long-term consumption of high-fat and high-calorie foods not only causes obesity, but also may cause a decline in sperm quality in men. Rats with abnormal lipid metabolism (high-fat rats) were established by high-fat diet for 24 weeks. HE staining was used to observe the morphological changes of testis in rats, TUNEL and flow cytometer was used to detect the cell apoptosis in rat testis and in vitro. Immunohistochemistry and Western blotting were used to detect the expression of protein. After 24 weeks of high-fat food feeding, the body weight, serum lipids and number of apoptotic spermatogenic cells in the high-fat group rat were significantly higher than those in the control group. In vivo, the expression of HSP60 protein in testis of high-fat rats was positive related to apoptosis of spermatogenic cells, cleaved caspase 3/caspase 3 protein expression and Bax/Bcl2 protein expression in testis of high-fat rats. Proportion of apoptotic spermatogenic cells was increased by up-regulation of HSP60 protein expression in vitro. Long-term consumption of high-fat diets can cause high expression of HSP60 and spermatogenic cells apoptosis in rats, while HSP60 over-expression promotes spermatogenic cell apoptosis and MAPK signal pathway in vitro.

Identification and characterization of chemical constituents in Qi-Lin pills and their metabolites in rat bio-samples after oral administration using ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry

Qi-Lin pill (QLP), a traditional Chinese medicine prescription (TCMP), composed of fifteen herbal medicines, has been widely used for the treatment of male infertility. However, an in-depth understanding of the chemical constituents of QLP and its in vivo metabolic study is lacking. In this study, a method using ultra-performance liquid chromatography coupled with quadruple time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was established for comprehensive analysis of chemical constituents of QLP and their metabolites in plasma, urine, bile and feces after gastric perfusion. The method guaranteed the fast discovery of representative structural fragment information and provided efficient structure clues for identification based on data from MS^E mode. As a result, a total of 202 constituents were unambiguously identified or tentatively characterized. In addition, a total of 203 QLP-related xenobiotics were characterized, including 41 (22 prototypes and 19 metabolites) in plasma, 144 (47 prototypes and 97 metabolites) in urine, 50 (27 prototypes and 23 metabolites) in bile and 68 (51 prototypes and 17 metabolites) in feces. The metabolism reactions included phase I reactions (demethylation, hydroxylation, deglycosylation, deoxygenation, hydrogenation, dehydration, oxidation and hydrolysis) and phase II reactions (methylation, conjugation with glucuronide and sulfate). This was the first comprehensive investigation on chemical constituents and metabolic profiles of QLP in vivo, and the results provided chemical foundation for further research on effective substances and action mechanism of QLP.

Compound heterozygosity for novel AURKC mutations in an infertile man with macrozoospermia

Among causes of infertility, teratozoospermia is characterised by a percentage of morphologically abnormal spermatozoa >4%. Macrozoospermia, one form of monomorphic teratozoospermia, is observed in <1% of cases of male infertility and is described as approximately 100% large-headed and/or multitailed spermatozoa. This study reports that an infertile man with large-head spermatozoa presenting compound heterozygosity aurora kinase C (AURKC) mutations (c.382C>T, c.572C>T) by whole-exome sequencing. Consequently, both two novel AURKC mutations had high probability of damage-causing and conserved across species and extremely low allele frequency in the population. Flow cytometry analysis revealed a high ratio of sperm DNA fragmentation. Two intracytoplasmic sperm injection (ICSI) procedures were attempted for the patient, but all were unsuccessful. These results indicate that sequence analysis should be performed for the variants of AURKC in Chinese patients with macrozoospermia.

Do lifestyle practices impede male fertility?

Alongside an increasing prevalence of couple and male infertility, evidence suggests there is a global declining trend in male fertility parameters over the past few decades. This may, at least in part, be explained through detrimental lifestyle practices and exposures. These include alcohol and tobacco consumption, use of recreational drugs (e.g., cannabis, opioids and anabolic steroids), poor nutritional habits, obesity and metabolic syndrome, genital heat stress (e.g., radiation exposure through cell phones and laptops, prolonged periods of sitting, tight-fitting underwear and recurrent hot baths or saunas), exposure to endocrine-disrupting chemicals (e.g., pesticide residue, bisphenol A, phthalates and dioxins) and psychological stress. This review discusses these lifestyle practices and the current evidence associated with male infertility. Furthermore, known mechanisms of action are also discussed for each of these. Common mechanisms associated with a reduction in spermatogenesis and/or steroidogenesis due to unfavourable lifestyle practices include inflammation and oxidative stress locally or systemically. It is recommended that relevant lifestyle practices are investigated in clinical history of male infertility cases, particularly in unexplained or idiopathic male infertility. Appropriate modification of detrimental lifestyle practices is further suggested and recommended in the management of male infertility.

Predicting Seminal Quality and its Dependence on Life Style Factors Through Ensemble Learning

The awareness related to fertility is of great importance due to the change in lifestyle habits. Semen analysis is a reliable confirmatory test to check the fertility in men. The supervised machine learning models of base classifiers include Decision Tree, Logistic Regression and Naive Bayes classifiers in which logistic regression shows a promising accuracy of 88%. Comparing with the bagging ensemble method for the weakest classifier, the results show a leap in accuracy from 78.80% to 90.02%. The authors have also attempted to design a novel voting classifier which votes over the ensemble learners and creates a more complex model to give an accuracy of 89%. Apart from this, the authors have also analyzed the receiver operating characteristic (ROC) curve for Extra Tree classifier which shows a 66% of area under the curve (AUC). The validation procedure used is a 5 fold cross-validation. The authors have further analyzed the lifestyle habits responsible for contributing to this problem based on impurity-based feature selection and have obtained ‘Age' as the most crucial factor in declining seminal quality.

Vitamins combined with traditional Chinese medicine for male infertility: A systematic review and meta-analysis

BACKGROUND

Male infertility is a tough problem in medicine. This article aims to provide the latest evidence for the efficacy and safety of traditional Chinese medicine (TCM) combined with vitamins in the treatment of male infertility.

METHOD

All randomized controlled trials (RCTs) that used TCM combined with vitamins for male infertility treatment were included in databases of China National Knowledge Infrastructure (CNKI), Wanfang, VIP Database, China Biology Medicine disc (CBM), MEDLINE, EMBASE, and Cochrane Library. The quality of the included articles was evaluated using the Cochrane Reviewer's Handbook 5.3, and meta-analysis was performed using Stata 15.

RESULTS

A total of 14 eligible studies with 1488 patients were included in this meta-analysis. The results suggested that, compared with vitamin E or vitamin E + C alone, combination of TCM with vitamins increased significantly sperm concentration, sperm motility, sperm viability, liquefaction time of semen, the activity of acrosome enzyme, and the pregnancy rate of patients with male infertility. Three kinds of TCM (Shengjing capsule, Huanshao capsule, and compound Xuanju capsule) showed significant improvement for male infertility in terms of pregnancy rate, sperm concentration, or sperm motility. In addition, the results of the publication bias test demonstrated that no significant bias occurred.

CONCLUSION

Traditional Chinese medicine combined with vitamins has significant efficacy in the treatment of male infertility with no increase in side effects. The specific implementing regulations still need more long-term, multicenter, randomized, and double-blind clinical trials.

Hypospermia Improvement in Dogs Fed on a Nutraceutical Diet

Male dog infertility may represent a serious concern in the canine breeding market. The aim of this clinical evaluation was to test the efficacy of a commercially available nutraceutical diet, enriched with Lepidium meyenii, Tribulus terrestris, L-carnitine, zinc, omega-3 (N-3) fatty acids, beta-carotene, vitamin E, and folic acid, in 28 male dogs suffering from infertility associated with hypospermia. All dogs received the diet over a period of 100 days. At the end of the evaluation period, no adverse effects, including head and tail anomalies percentage onset, were reported. Interestingly, motility percentage, semen volume and concentration, and total number of sperms per ejaculation significantly increased. Further investigations on a wider cohort of dogs might be useful to better correlate the presence of oxytetracycline in pet's diet and the onset of infertility and clearly assess the action mechanism of an oxytetracycline-free nutraceutical diet.

Association between expression of TNF-α, P53 and HIF1α with asthenozoospermia

Reduced sperm motility (asthenozoospermia) accounts for a significant percentage of male infertility and numerous factors have been suggested to explain this phenomenon among which hypoxic and inflammatory markers are the least studied. Therefore, the aim of this study was to assess the main molecular markers involved in hypoxia (P53 and HIF-1α) and inflammation (TNF-α) pathways in infertile men with asthenozoospermia. Expression of these markers were assessed by qRT-PCR, and analysis of data show that mean of hypoxia markers (P53, HIF-1α) and also TNF- α were significantly higher in infertile men with asthenozoospermia compared to fertile men (p < 0.05). Unlike TNF-α, significant negative correlations were observed between expression of P53 (r = -0.568; p = 0.002) and HIF-1α (r = -0.403; p = 0.046) with sperm motility. In addition, a significant negative correlation was observed between expression of P53 with sperm concentration (r = -0.576; p < 0.001). In addition, a significant positive correlation was observed between hypoxia markers (P53, HIF-1α) and TNF-α (p < 0.01). However, no significant relation was observed between TNF-α and semen parameters. Taken together, the results of this study suggest the involvement of hypoxia pathway is more pronounced than the inflammatory pathway in asthenozoospermia.

The Therapeutic Effects of Traditional Chinese Medicine for Poor Semen Quality in Infertile Males

Poor sperm quality is one of the main factors of male infertility. Traditional Chinese Medicine (TCM) has been used frequently in clinical practice in many countries to treat a wide array of infertile problems. To further understand the effects of TCM on semen quality, we retrospectively enrolled patients with male infertility and poor semen quality at the Tainan Municipal Hospital in Taiwan between 2013 and 2016. Semen quality analysis in accordance with the WHO criteria is an essential step in the evaluation of male fertility status. Associations between the semen parameters and body mass index, smoking status, alcohol use, duration of infertility, and age were also analyzed. A total of 126 male infertility patients with abnormal semen analysis were included in this study: 50 TCM users and 13 TCM non-users. The basic characteristics of the two groups were not significantly different. TCM users account for 92.5% of the total semen improvement subjects. In conclusion, TCM supplementation may have a beneficial role as improving sperm quality for infertility patients.

Evaluation of the Spermatogenic Activity of Polyherbal Formulation in Oligospermic Males

The therapeutic use of natural herbs is an ancient human civilization act and the numbers of people have reliance on their pharmacological properties and preferred to use the natural herbs. People also use to consume these herbs as supplements to energize, bolster, and eventually enhance sexual ability. Polyherbal formulation (PHF) is one of these herbal amalgams that can be used to treat sexual dysfunction including erectile dysfunction, impotence, ejaculation dysfunction, and hypogonadism. The pilot study was aimed at evaluating the capacity of PHF in enhancing the spermatogenic potential of oligospermic patients. Thirty-six male patients with oligospermia were enrolled and randomized either to treatment (n = 23) with PHF (750 mg/d in three doses for 90 days) or to placebo (n = 13) in the same protocol. The preintervention semen analysis was compared with posttreatment semen analysis. Based on the postintervention semen analysis, patients were advised to undergo either in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) to assess their fertility status. After polyherbal treatment, there was a 256% increase in sperm concentration (9.59 ± 4.37 × 106/mL to 25.61 ± 8.6 × 10⁶/mL; P ≤0.001), 154% increase in semen volume (1.7 ± 0.14 mL to 4.32 ± 0.38 mL; P ≤0.001), and 215% increase in sperm motility (15.43 ± 2.40% to 48.65 ± 5.10%; P ≤ 0.001) on day 90 from baseline. Furthermore, a significant improvement and regulation were also observed in serum hormone levels with PHF treatment as compared to the placebo group. The present study demonstrated the evidence on synergistic spermatogenic effect of PHF as attributed in ayurveda for the treatment of oligospermia leading to infertility.

Therapeutic Role of Green Tea Polyphenols in Improving Fertility: A Review

Sperm cells are highly sensitive to reactive oxygen species (ROS), which are produced during cellular oxidation. In normal cell biology, ROS levels increase with a decreasing antioxidant response, resulting in oxidative stress which threatens sperm biology. Oxidative stress has numerous effects, including increased apoptosis, reduced motion parameters, and reduced sperm integrity. In this regard, green tea polyphenols (GrTPs) have been reported to possess properties that may increase the quality of male and female gametes, mostly via the capability of catechins to reduce ROS production. GrTPs have antioxidant properties that improve major semen parameters, such as sperm concentration, motility, morphology, DNA damage, fertility rate, and gamete quality. These unique properties of green tea catechins could improve reproductive health and represent an important study area. This exploratory review discusses the therapeutic effects of GrTPs against infertility, their possible mechanisms of action, and recommended supportive therapy for improving fertility in humans and in animals.

Profertility effects of Shilajit on cadmium-induced infertility in male mice

Shilajit is claimed as a Vajikarak (aphrodisiac) and used for the treatment of male infertility by traditional healers of the Indian subcontinent. Therefore, the present investigation was designed to assess the effectiveness of Shilajit for treatment of male infertility resulting from exposure to perilous chemicals. Effect of daily oral administration (p.o.) of Shilajit (50 mg, 100 mg and 200 mg/Kg BW) was investigated for a single spermatogenic cycle (35 days) in cadmium-induced (2 mg/Kg BW, p.o. for 35 days) infertile adult (12-14 week) swiss male mice. Shilajit treatment increased weights of reproductive organs, testicular daily sperm production, activities of testicular Δ⁵ 3β-HSD and 17 β-HSD enzymes and serum level of testosterone. Histopathological evaluation of testis revealed that Shilajit restored spermatogenesis as reflected by a gradual augmentation in germ cell layers with increased doses of Shilajit compared to cadmium-treated mice. Further, Shilajit treatment reverted back the adverse effects of cadmium on motility and concentration of spermatozoa. Secretory activities of the epididymis and seminal vesicle and libido, fertility and the number of litters per female were also improved by Shilajit in cadmium-treated mice. Results thus suggest the potent androgenic nature of Shilajit and its role in fertility improvement against cadmium-induced infertility.

Association Between Nonalcoholic Fatty Liver Disease and Severe Male Reproductive Organ Impairment (Germinal Epithelial Loss): Study on a Mouse Model and on Human Patients

Metabolic syndrome (MS) has been associated with testicular damage. Nonalcoholic fatty liver disease (NAFLD) is a multisystemic disease that affects different organs, but its effect on the testes is unknown. A study analyzing germ cell involvement on BALB/c mice was carried out. A parallel comparative study was conducted that investigated alterations in the germinal epithelium of male humans that died from an unrelated acute event. The complete medical histories and histologic samples of the thoracic aorta, liver tissue, and testicular tissue from the deceased subjects were collected. The degree of germinal epithelial loss (DGEL) was evaluated and the clinical and histologic data were compared between individuals with and without NAFLD. The only metabolic or morphologic variable that caused a significant difference in the DGEL, in both the animal model and humans, was the presence of liver steatosis. The percentage of steatosis was also correlated with the percentage of the DGEL. In humans, steatosis (greater than 20%) increased the risk 12-fold for presenting with a severe DGEL (OR: 12.5; 95% CI [1.2, 128.9]; p = .03). There was no association with age above 50 years or MS components. Steatosis grade was also correlated with atherosclerosis grade. NAFLD was a strongly associated factor implicated in severe DGEL, as well as the testis was identified as a probable target organ for damage caused by the disease. This finding could result in the search for new approach strategies in the management of men with fertility problems. Further studies are required to confirm these results.

Pectinase-treated Panax ginseng protects heat stress-induced testicular damage in rats

Testicular hyperthermia is well studied to cause impaired spermatogenesis. In the present study, the protective effect of enzymatically modified (pectinase-treated) Panax ginseng (GINST) against intermittent sub-chronic heat stress-induced testicular damage in rats was investigated. Male Sprague-Dawley rats were divided into four groups: normal control (NC), heat-stressed control (HC), heat-stressed plus GINST-100 mg/kg/day (HG100) and heat-stressed plus GINST-200 mg/kg/day (HG200) treatment groups. GINST (100 and 200 mg/kg/day) was mixed separately with a regular pellet diet and was administered orally for 8 weeks starting from 1 week before heat exposure. Parameters such as organ weight, blood chemistry, sperm kinetic values, expression of antioxidant enzymes, spermatogenesis molecules and sex hormone receptors levels were measured. Data revealed that kidney and epididymis weight were significantly (P < 0.05) decreased with heat stress and recovered by GINST treatment. Further, the altered levels of blood chemistry panels and sperm kinetic values in heat stress-induced rats were attenuated when GINST was administered (P < 0.05). Furthermore, the expression levels of antioxidant-related enzymes (GSTM5 and GPX4), spermatogenesis-related proteins (CREB1 and INHA) and sex hormone receptors (androgen receptor, luteinizing hormone receptor and follicle-stimulating hormone receptor) were reduced by heat stress; however, GINST treatment effectively ameliorated these changes. In conclusion, GINST was effective in reducing heat-induced damage in various male fertility factors in vivo and has considerable potential to be developed as a useful supplement in improving male fertility.

Smoke, alcohol and drug addiction and male fertility

In recent decades, the decline in human fertility has become increasingly more worrying: while therapeutic interventions might help, they are vexing for the couple and often burdened with high failure rates and costs. Prevention is the most successful approach to fertility disorders in males and females alike. We performed a literature review on three of the most common unhealthy habits - tobacco, alcohol and drug addiction - and their reported effects on male fertility. Tobacco smoking is remarkably common in most first-world countries; despite a progressive decline in the US, recent reports suggest a prevalence of more than 30% in subjects of reproductive age - a disturbing perspective, given the well-known ill-effects on reproductive and sexual function as well as general health. Alcohol consumption is often considered socially acceptable, but its negative effects on gonadal function have been consistently reported in the last 30 years. Several studies have reported a variety of negative effects on male fertility following drug abuse - a worrying phenomenon, as illicit drug consumption is on the rise, most notably in younger subjects. While evidence in these regards is still far from solid, mostly as a result of several confounding factors, it is safe to assume that cessation of tobacco smoking, alcohol consumption and recreational drug addiction might represent the best course of action for any couple trying to achieve pregnancy.