Is male fertility associated with type 2 diabetes mellitus?

Early onset type 2 diabetes mellitus: an update

The incidence and prevalence of type 2 diabetes mellitus (T2DM) in young individuals (aged <40 years) have significantly increased in recent years, approximating two to threefold increase in the respective rates. Numerous risk factors including severe obesity, family history, ethnicity, maternal diabetes or gestational diabetes, and female sex contribute to a younger age of onset. In terms of pathogenesis, impaired insulin secretion is the key operating mechanism, alongside with ectopic adiposity-related insulin resistance. T2DM diagnosis in a young adult requires the exclusion of type 1 diabetes mellitus (T1DM), latent autoimmune diabetes of adults (LADA) and maturity-onset diabetes of the young (MODY). The establishment of such diagnosis is critical for prognosis, because early-onset T2DM is associated with rapid deterioration in pancreatic β-cell secretory function leading to earlier initiation of insulin therapy. Furthermore, mortality and lifetime risk of developing complications, especially microvascular, is increased in these patients compared to both later-onset T2DM and T1DM patients; also, the latter are often developed earlier in the course of disease. The management of early-onset T2DM follows the same guidelines as in later-onset T2DM; yet patients aged 18-39 years are underrepresented in the big clinical trials on which the development of guidelines is based. Finally, young people with T2DM face significant challenges associated with social determinants, which compromise their adherence to therapy and induce diabetes distress. Future research focusing on the pathogenesis of β-cell decline and complications, as well as on specific treatment shall lead to better understanding and management of early-onset T2DM.

Diabetes and male fertility disorders

Couple infertility is a common condition, defined as being unable to conceive after 12 months of regular unprotected sexual intercourse. Male Factor Infertility (MFI) is responsible, alone or in combination with female factors, for about half of the overall cases of couple infertility. MFI is gradually increasing in prevalence, with a notable decline in semen parameters over the last decades. The aetiologies behind the finding of decreasing sperm counts are difficult to pinpoint but might be due in part to increasing rates of overweight and obesity in men of childbearing age. Diabetes mellitus (DM) is a common and chronic metabolic disease, whose prevalence is also gradually increasing, rising up to 10% of the population. The International Diabetes Federation estimates that there are currently more than 500 million people living with DM worldwide, the vast majority of whom suffering from type 2 DM (T2DM). There is growing awareness of the relationship between unhealthy lifestyle, in particular unhealthy diet, and MFI. Starting from all these premises, the aim of this narrative review is to describe the current evidence on the link between DM and MFI, both in terms of DM as a cause of/a risk factor for MFI and of MFI as a possible predictive marker for T2DM. Finally, we will discuss the risk of DM as a consequence of the therapy of MFI or assisted reproductive techniques.

DNA Aptamer Raised against Advanced Glycation End Products Improves Sperm Concentration, Motility, and Viability by Suppressing Receptors for Advanced Glycation End Product-Induced Oxidative Stress and Inflammation in the Testes of Diabetic Mice

Type 2 diabetes mellitus (T2DM) is a risk factor for male infertility, but the underlying molecular mechanisms remain unclear. Advanced glycation end products (AGEs) are pathogenic molecules for diabetic vascular complications. Here, we investigated the effects of the DNA aptamer raised against AGEs (AGE-Apt) on testicular and sperm abnormalities in a T2DM mouse model. KK-Ay (DM) and wild-type (non-DM) 4- and 7-week-old male mice were sacrificed to collect the testes and spermatozoa for immunofluorescence, RT-PCR, and histological analyses. DM and non-DM 7-week-old mice were subcutaneously infused with the AGE-Apt or control-aptamer for 6 weeks and were then sacrificed. Plasma glucose, testicular AGEs, and Rage gene expression in 4-week-old DM mice and plasma glucose, testicular AGEs, oxidative stress, and pro-inflammatory gene expressions in 7-week-old DM mice were higher than those in age-matched non-DM mice, the latter of which was associated with seminiferous tubular dilation. AGE-Apt did not affect glycemic parameters, but it inhibited seminiferous tubular dilation, reduced the number of testicular macrophages and apoptotic cells, and restored the decrease in sperm concentration, motility, and viability of 13-week-old DM mice. Our findings suggest that AGEs-Apt may improve sperm abnormality by suppressing AGE-RAGE-induced oxidative stress and inflammation in the testes of DM mice.

Effects of garlic (Allium sativum L) and Citrullus colocynthis (L.) Schrad individually and in combination on male reproductive damage due to diabetes: suppression of the AGEs/RAGE/Nox-4 signaling pathway

BACKGROUND

Diabetes Mellitus is associated with disturbances in male reproductive function and fertility. Studies have shown that oxidative stress with the subsequent inflammation and apoptosis cause these complications in diabetes. Garlic (G) (Allium sativum L) and Citrullus colocynthis (L.) Schrad (C) both have antidiabetic and antioxidant properties. Recently, we demonstrated their synergistic effects in alleviating reproductive complications when administered concomitantly. However, as even medicinal plants in long term usage may lead to some unwanted side effects of their own, we examined whether with half the original doses of these two medicinal plants we could achieve the desired results.

METHODS

Thirty-five male Wistar rats were divided into five groups (n = 7/group): Control, Diabetic, Diabetic + G (0.5 ml/100 g BW), Diabetic + C (5 mg/kg BW) and Diabetic + GC (0.5 ml/100 g BW of garlic and 5 mg/kg BW of C. colocynthis) groups. The experimental period was 30 days.

RESULTS

Oxidative stress, advanced glycation end products (AGEs), immunoexpression of caspase-3, and expression of mRNAs for receptor for advanced glycation end products (RAGE), NADPH oxidase-4 (NOX-4) and nuclear factor kappa B increased in testis of diabetic rats. Treatment with garlic and C. colocynthis alone showed some beneficial effects, but in the combination form the effectiveness was more profound.

CONCLUSIONS

We conclude that the combination therapy of diabetic rats with lower doses is still as efficient as higher doses; therefore, the way forward for reducing complications in long term consumption.

Male patients with inflammatory joint diseases are less likely than controls to be childless: results from a Norwegian population-based cohort study of 10 865 patients

OBJECTIVES

To investigate the number of children per man and the proportion of childless men as a proxy of fertility in a national cohort of men with inflammatory joint diseases (IJDs), compared with matched controls from the general population.

METHODS

This is a nationwide, population-based retrospective cohort study. Male patients with IJDs (n = 10 865) in the Norwegian Arthritis Registry were individually matched 1:5 on birth year and county of residence with men without IJDs obtained from the National Population Register (n = 54 325). Birth data were obtained from the Medical Birth Registry of Norway. We compared the mean number of children per man and the proportion of childless men and analysed the impact of age and year of diagnosis.

RESULTS

The mean number of children per man in the patient group was 1.80 versus 1.69 in the comparison group (p <0.001), and 21% of the patients in the patient group were childless versus 27% in the comparison group (p <0.001). The finding of less childlessness and higher number of children per man remained consistent across age at diagnosis, except for those diagnosed at age 0-19 years. The difference in childlessness was most pronounced for men diagnosed after year 2000, especially when diagnosed at 30-39 years of age (22% vs 32%, p<0.001).

CONCLUSION

In this large cohort study we found that patients with IJD have a higher number of children and are less likely to be childless compared with controls. Factors associated with developing or having an IJD might influence fertility and this requires further investigation.

Diabetes-induced male infertility: potential mechanisms and treatment options

Male infertility is a physiological phenomenon in which a man is unable to impregnate a fertile woman during a 12-month period of continuous, unprotected sexual intercourse. A growing body of clinical and epidemiological evidence indicates that the increasing incidence of male reproductive problems, especially infertility, shows a very similar trend to the incidence of diabetes within the same age range. In addition, a large number of previous in vivo and in vitro experiments have also suggested that the complex pathophysiological changes caused by diabetes may induce male infertility in multiple aspects, including hypothalamic-pituitary-gonadal axis dysfunction, spermatogenesis and maturation disorders, testicular interstitial cell damage erectile dysfunction. Based on the above related mechanisms, a large number of studies have focused on the potential therapeutic association between diabetes progression and infertility in patients with diabetes and infertility, providing important clues for the treatment of this population. In this paper, we summarized the research results of the effects of diabetes on male reproductive function in recent 5 years, elaborated the potential pathophysiological mechanisms of male infertility induced by diabetes, and reviewed and prospected the therapeutic measures.

Dapagliflozin ameliorates diabetes-induced spermatogenic dysfunction by modulating the adenosine metabolism along the gut microbiota-testis axis

Male infertility is one of the most common complications of diabetes mellitus (DM). Dapagliflozin is widely used to manage the type II DM. This study aimed to assess the dapagliflozin's effects on the spermatogenesis by administering either dapagliflozin (Dapa) or vehicle (db) to male db/db mice, and using littermate male db/m mice as the control (Con). We further performed the integrative analyses of the cecal shotgun metagenomics, cecal/plasmatic/testicular metabolomics, and testicular proteomics. We found that dapagliflozin treatment significantly alleviated the diabetes-induced spermatogenic dysfunction by improving sperm quality, including the sperm concentration and sperm motility. The overall microbial composition was reshaped in Dapa mice and 13 species (such as Lachnospiraceae bacterium 3-1) were regarded as potential beneficial bacteria. Metabolites exhibited modified profiles, in which adenosine, cAMP, and 2'-deoxyinosine being notably altered in the cecum, plasma, and testis, respectively. Testicular protein expression patterns were similar between the Dapa and Con mice. In vivo results indicated that when compared with db group, dapagliflozin treatment alleviated apoptosis and oxidative stress in testis tissues by down-regulating 2'-deoxyinosine. This was further validated by in vitro experiments using GC-2 cells. Our findings support the potential use of dapagliflozin to prevent the diabetes-induced impaired sperm quality and to treat diabetic male infertility.

Type 2 diabetes mellitus and the risk of male infertility: a Mendelian randomization study

Objective

To assess the causal effect of type 2 diabetes mellitus (T2DM) on male infertility (MI) and erectile dysfunction (ED) by Mendelian randomization (MR) analysis.

Methods

Data for T2DM, MI, and ED were obtained from genome-wide association studies (GWAS) involving 298, 957, 73, 479, and 223, 805 Europeans, respectively. We performed univariate MR analysis using MR Egger, Weighted median (WM) and Inverse variance weighted (IVW) methods to assess causal effects among the three. Through the Genotype Tissue Expression (GTEx) database, single-nucleotide polymorphisms (SNPs) that affect the expression levels of T2DM-related genes were located using expression quantitative trait loci (eQTL).

Results

MR analysis showed a significant causal relationship between T2DM and ED (WM, OR: 1.180, 95%CI: 1.010-1.378, P = 0.037; IVW, OR: 1.190, 95%CI: 1.084-1.300, P < 0.001). There is also a significant causal relationship between T2DM and MI (MR Egger, OR: 0.549, 95%CI: 0.317-0.952, P = 0.037; WM, OR: 0.593, 95%CI: 0.400, P = 0.010; IVW, OR: 0.767, 95%CI: 0.600-0.980, P = 0.034). ED may not cause MI (P > 0.05). We also found that rs6585827 corresponding to the PLEKHA1 gene associated with T2DM is an eQTL variant affecting the expression of this gene.

Conclusion

T2DM has a direct causal effect on ED and MI. The level of PLEKHA1 expression suppressed by rs6585827 is potentially associated with a lower risk of T2DM.

Sperm DNA damage: The possible link between obesity and male infertility, an update of the current literature

Obesity prevalence worldwide is increasing significantly. Whilst maternal obesity has clear detrimental impacts on fertility, pregnancy and foetal outcomes, more recently there has been an increasing focus on the role of paternal obesity in human fertility. Recent meta-analyses have indicated that obesity in men negatively affects basic sperm parameters such as sperm count, concentration and motility, increases the incidence of infertility and reduces the chances of conception. Sperm DNA damage, typically characterised by DNA strand breaks and oxidation of DNA nucleotides, is a specialised marker of sperm quality that has been independently associated with recurrent miscarriage, reduced assisted reproduction success and increased mutational loads in subsequent offspring. Whilst, there are still conflicting data in humans as to the association of obesity in men with sperm DNA damage, evidence from rodent models is clear, indicating that male obesity increases sperm DNA damage. Human data are often conflicting because of the large heterogeneity amongst studies, the use of body mass index as the indicator of obesity and the methods used for detection of sperm DNA damage. Furthermore, comorbidities of obesity (i.e., heat stress, adipokines, insulin resistance, changes in lipids, hypogonadism and obstructive sleep apnoea) are also independently associated with increased sperm DNA damage that is not always modified in men with obesity, and as such may provide a causative link to the discrepancies amongst human studies. In this review, we provide an update on the literature regarding the associations between obesity in men and fertility, basic sperm parameters and sperm DNA damage. We further discuss potential reasons for the discrepancies in the literature and outline possible direct and indirect mechanisms of increased sperm DNA damage resulting from obesity. Finally, we summarise intergenerational obesity through the paternal linage and how sperm DNA damage may contribute to the transmission.

Garden Cress Seed Oil Abrogates Testicular Oxidative Injury and NF-kB-Mediated Inflammation in Diabetic Mice

Diabetes mellitus is a metabolic disorder associated with various complications encompassing male reproductive dysfunction. The present study aimed to investigate the therapeutic potential of biologically active Lepidium sativum seed oil (LSO) against the testicular dysfunction associated with streptozotocin (STZ)-induced diabetes. Male adults (n = 24) were divided into four groups: control, LSO-administered, diabetic (D), and LSO-treated diabetic (D+LSO) groups. LSO was extracted from L. sativum seeds, and its chemical composition was determined using GC-MS. Serum testosterone levels, testicular enzymatic antioxidants (catalase (CAT) and superoxide dismutase (SOD)), an oxidative stress (OS) biomarker, malondialdehyde (MDA), pro-inflammatory markers (NF-kB, IL-1, IL-6, and TNF-α), and the expression level of NF-kB were assessed. In addition, histopathological changes were evaluated in testicular tissues. The results obtained showed that the chemical composition of LSO indicated its enrichment mainly with γ-tocopherol (62.1%), followed by 2-methylhexacosane (8.12%), butylated hydroxytoluene (8.04%), 10-Methylnonadecane (4.81%), and δ-tocopherol (3.91%). Moreover, LSO administration in the D+LSO mice significantly increased testosterone levels and ameliorated the observed testicular oxidative damage, inflammatory response, and reduced NF-kB expression compared to the diabetic mice. Biochemical and molecular analyses confirmed the histological results. In conclusion, LSO may prevent the progression of diabetes-induced impairment in the testes through inhibition of the OS- and NF-kB-mediated inflammatory response.

Consequences of Type-2 diabetes mellitus and Malaria co-morbidity on sperm parameters in men; a case-control study in a district hospital in the Ashanti Region of Ghana

Type-2 diabetes mellitus (T2DM) and malaria infection are highly prevalent in Africa particularly, in the Sub-Saharan Region. A greater number of people in the Ghanaian population who have T2DM are also reported to harbor malaria parasites. This study aimed to investigate the influence of T2DM & Malaria co-morbidity on sperm parameters among patients in the Ashanti Region of Ghana. This hospital-based cross-sectional analytic case-control study comprised 254 adult male study participants comprising 80 T2DM & Malaria co-morbidity, 80 T2DM only, and 94 normal controls. A blood sample (10mL) was drawn from each participant to measure FBG, HbA1c levels, Testosterone levels, Total cholesterol, and determination of Malaria parasite density. Seminal fluid was also collected from each participant for semen analysis. Sperm kinetics of the T2DM & Malaria co-morbidity group particularly; total motility, rapid progressive motility, and slow progressive motility were negatively affected compared to both T2DM only (p<0.0001) and the Normal control (p<0.0001). Normal sperm morphology was significantly affected in the co-morbidity group compared to T2DM only (p<0.0001). Sperm vitality was also statistically significantly reduced in the T2DM & Malaria co-morbidity than in T2DM only (t (64) = -8.62; p<0.001). There was a significant decline in testosterone levels in the T2DM & Malaria co-morbidity group than in the T2DM only (p<0.0001) and the control (p <0.0001). In conclusion, T2DM and malaria infection have a stronger propensity to alter sperm morphology and lower sperm motility and vitality.

The effect of zinc supplementation on improving sperm parameters in infertile diabetic men

Background and aims

Diabetes mellitus (DM) may have different adverse effects on the male reproductive system. Zinc (Zn) is one of the necessary elements in the human and mammalian diet that plays an important role in scavenging reactive oxygen species (ROS) by providing antioxidant and anti-apoptotic properties. The aim of this study was to determine the protective effects of zinc supplements on sperm chromatin and the evaluation of sperm deoxyribonucleic acid (DNA) integrity in diabetic men.

Methods

In this interventional study, 43 infertile Iranian men in diabetic and non-diabetic groups were included. They were then randomly divided into two subgroups: normal saline intake and zinc sulfate intake (25 mg orally for 64 days each). Different indices of sperm analysis (number, morphology and motility) and testosterone levels were evaluated in four groups. Protamine deficiency and DNA fragmentation were assessed using chromomycin A3 (CMA3) and sperm chromatin dispersion (SCD) methods, respectively.

Results

Zinc supplementation reduced the deformity of neck and head of sperms (p < 0.05), as well as deformity of sperm tail in infertile diabetic men. Zinc administration ameliorated sperm motility types A, B and C (p < 0.05). Moreover, zinc administration reduced abnormal morphology and DNA fragmentation of sperms, which increased the SCD1 and SCD2 and reduced the SCD3 and SCD4 in both treated groups.

Conclusion

Zinc supplementation, as a powerful complement, is able to balance the effect of diabetes on sperm parameters, sperm chromatin and DNA integrity. Consequently, zinc supplementation can probably be considered a supportive compound in the diet of diabetic infertile men.

Effects of diabetes mellitus on sperm quality and fertility outcomes: Clinical evidence

BACKGROUND

Diabetes mellitus is a global epidemic characterized by high morbidity and mortality. Diabetes mellitus can lead to acute and chronic systemic complications. Among them, a negative effect of diabetes mellitus on sperm quality and male/couple fertility has been suggested. However, available studies in diabetes mellitus men evaluated relatively small cohorts with discordant results.

OBJECTIVES

To evaluate the clinical evidences of the effects of diabetes mellitus on sperm quality and fertility outcomes.

METHODS

An extensive Medline search was performed identifying studies in the English language.

RESULTS

The prevalence of diabetes mellitus in infertile men ranges from 0.7% to 1.4%, while the prevalence of infertility in diabetes mellitus men, evaluated in a few studies, ranges from 35% to 51%. Male diabetes mellitus seems to play a negative effect on couple fecundity, while being childless or subfertile men might increase the risk of diabetes mellitus. Available cross-sectional studies investigating semen parameters and male sexual hormones in men with diabetes mellitus are heterogeneous, assessed relatively small cohorts, show often discordant results and frequently are not directly comparable to derive robust conclusions. Two meta-analyses support a negative effect of diabetes mellitus on sperm normal morphology and no effect on sperm total count, with contradictory results regarding other semen parameters. Considering only studies on type 1 diabetes mellitus men, meta-analyses support a negative effect of diabetes mellitus on sperm motility and no effect on sperm total count, with contradictory results regarding other semen parameters. The rate of children observed among type 1 diabetes mellitus men was lower than controls, especially in subjects with a longer diabetes mellitus duration. Couples with a diabetes mellitus male partner undergoing assisted reproduction techniques showed lower pregnancy rates than controls. No study evaluated the impact of diabetes mellitus treatment on semen quality and male fertility.

CONCLUSIONS

Overall, available data show that diabetes mellitus might impair male reproductive health and couple fertility. However, further larger and full of details studies are needed.

A systematic review on anti-diabetic plant essential oil compounds: Dietary sources, effects, molecular mechanisms, and safety

Type 2 diabetes mellitus (T2DM) is a multifaceted metabolic syndrome defined through the dysfunction of pancreatic β-cells driven by a confluence of genetic and environmental elements. Insulin resistance, mediated by interleukins and other inflammatory elements, is one of the key factors contributing to the progression of T2DM. Many essential oils derived from dietary plants are beneficial against various chronic diseases. We reviewed the anti-diabetic properties of dietary plant-derived essential oil compounds, with a focus on their molecular mechanisms by modulating specific signaling pathways and other critical inflammatory mediators involved in insulin resistance. High-quality literature published in the last 12 years, from 2010 to 2022, was collected from the Scopus, Web of Science, PubMed, and Embase databases using the search terms "dietary plants," "essential oils," "anti-diabetic," "insulin resistance," "antihyperglycemic," "T2DM," "anti-diabetic essential oils," and anti-diabetic mechanism." According to the results, the essential oil compounds, including cinnamaldehyde, carvacrol, zingerone, sclareol, zerumbone, myrtenol, thujone, geraniol, citral, eugenol, thymoquinone, thymol, citronellol, α-terpineol, and linalool have been demonstrated to contain strong anti-diabetic effects via modulating various signal transduction pathways linked to glucose metabolism. Additionally, in diabetes-related animal models, they can also considerably reduce the expression of TNF-α, IL-1β, IL-4, IL-6, iNOS, and COX-2. The main signaling molecules regulated by these compounds include AMPK, GLUT4, Caspase-3, PPARγ, PPARα, NF-κB, p-IκBα, MyD88, MCP-1, SREBP-1c, AGEs, RAGE, VEGF, Nrf2/HO-1, and SIRT-1. They can also significantly inhibit the generation of TBARS and MDA, reduce oxidative stress, increase insulin levels, adiponectin, and glycoprotein enzymes, boost antioxidant enzymes like SOD, CAT, and GPx, as well as reduce glutathione and vital glycolytic enzymes. Besides, they can significantly lower the levels of liver enzymes and lipid profile markers. Moreover, most essential oil compounds are generally safe based on animal studies. In conclusion, dietary plant-derived essential oil compounds have potential anti-diabetic effects by influencing different signaling pathways and molecular targets linked to glucose metabolism, and should be safe and beneficial against diabetes and related complications.

Male infertility and somatic health - insights into lipid damage as a mechanistic link

Over the past decade, mounting evidence has shown an alarming association between male subfertility and poor somatic health, with substantial evidence supporting the increased incidence of oncological disease, cardiovascular disease, metabolic disorders and autoimmune diseases in men who have previously received a subfertility diagnosis. This paradigm is concerning, but might also provide a novel window for a crucial health reform in which the infertile phenotype could serve as an indication of potential pathological conditions. One of the major limiting factors in this association is the poor understanding of the molecular features that link infertility with comorbidities across the life course. Enzymes involved in the lipid oxidation process might provide novel clues to reconcile the mechanistic basis of infertility with incident pathological conditions. Building research capacity in this area is essential to enhance the early detection of disease states and provide crucial information about the disease risk of offspring conceived through assisted reproduction.

Arthrospira platensis nanoparticles defeat against diabetes-induced testicular injury in rat targeting, oxidative, apoptotic, and steroidogenesis pathways

Varieties of studies have been used to investigate the health benefits of Spirulina (Arthrospira platensis); however, more research is needed to examine if its nano form may be utilized to treat or prevent several chronic diseases. So, we designed this study to explore the effect and the cellular intracellular mechanisms by which Arthrospira platensis Nanoparticles (NSP) alleviates the testicular injury induced by diabetes in male Wistar rats. Eighty Wistar male rats (n = 80) were randomly allocated into eight groups. Group 1 is untreated rats (control), Group 2 including STZ-induced diabetic rats with 65 mg/kg body weight STZ (STZ-diabetic), Group 3-5: including diabetic rats treated with NSP1, NSP2, and NSP3 at 0.25, 0.5, and 1 mg/kg body weight, respectively, once daily orally by the aid of gastric gavage for 12 consecutive weeks and groups 6-8 include normal rats received NSP (0.25, 0.5, and 1 mg/kg body weight once daily orally. The identical volume of normal saline was injected into both control and diabetic rats. After 12 weeks of diabetes induction, the rats were killed. According to our findings, NSP administration to diabetic rats enhances the total body weight and the weight of testes and accessory glands; in addition, NSP significantly reduced nitric oxide and malondialdehyde in testicular tissue improved sperm parameters. Intriguingly, it raises testicular GSH and SOD activity by a significant amount (p < 0.05). As well, Oral administration of NSP to diabetic rats resulted in a decrease in the blood glucose levels, HA1C, induced in the diabetic group, which overcame the diabetic complications NSP caused down-regulation of apoptotic genes with upregulation of BCL-2 mRNA expression (p < 0.05) and prominent up-regulation of steroidogenesis genes expression level in testes in comparison to the diabetic rats which resulted in improving the decreased levels of testosterone hormone, FSH, and LH induced by diabetes. In the same way, our histopathological findings support our biochemical and molecular findings; in conclusion, NSP exerted a protective effect against reproductive dysfunction induced by diabetes not only through its high antioxidant and hypoglycemic action but also through its down-regulation of Apoptotic genes and up-regulation of steroidogenesis regulatory genes expression level in diabetic testes.

Managing Sexual and Reproduction Complications of Diabetes in Men

Male reproductive disorders are a less discussed complication of diabetes. These disorders can include balanitis, erectile dysfunction, decreased libido, erectile impotence, and infertility. This article reviews the epidemiology, pathophysiology, classic presentation, and treatment of balanitis, erectile dysfunction, and sperm dysfunction.

Effect of combined calcium, magnesium, vitamin C and E supplementation on seminal parameters and serum oxidative stress markers in fructose-induced diabetic Wistar rats

CONTEXT

Deleterious effects of diabetes on seminal quality, serum metals and antioxidants have been confirmed.

OBJECTIVE

This study evaluated the effect of combined calcium, magnesium, vitamin C and E supplementation on seminal parameters, serum total antioxidant capacity (TAC), nitric oxide (NO), malonyldialdehyde (MDA), calcium and magnesium in fructose-induced diabetic rats.

MATERIALS AND METHODS

Thirty rats were grouped into non-diabetic controls, diabetic controls, diabetic rats given vitamin E + C, calcium + magnesium and vitamin E + C + calcium + magnesium. The analytes were evaluated using standard methods. Statistical significance was set at p < .05.

RESULTS

The diabetic controls had significantly higher MDA (p = .036) but lower (p = .0001) TAC, calcium, magnesium, sperm count, and %motility than the non-diabetic controls. The Vitamin C + E group showed the greatest improvement as they had the highest values of seminal parameters compared to other supplemented groups.

CONCLUSION

Combined Vitamin C + E supplementation may provide better ameliorative benefits than a combination of Vitamin C, E, calcium and magnesium in diabetics.

Influence of physical activity on male fertility

Infertility is a worldwide issue impacting 15% of couples' population. Male-related infertility results in almost 50% of these cases. Considering lifestyle factors associated with infertility, here in this literature review article, we aimed to discuss training/sport effects on male-related infertility. Regarding this issue, human and animal model studies related to the subject were gathered and analysed. Exercise is well known as a general improving factor, however, excessive exercise can result in male infertility due to reduced hypothalamus-pituitary-gonadal axis (HPT) function, increased oxidative stress and chronic inflammation. Consequently, these underlying impacts result in a low testosterone production, and reduced semen quality, and can lead to infertility. In contrast, it has been revealed that exercise can improve male fertility status in lifestyle-induced infertility condition such as obesity and diabetes. Indeed, exercise, by increasing testicular antioxidant defence, reducing pro-inflammatory cytokines level and enhancing the steroidogenesis process, leads to improved spermatogenesis and semen quality in lifestyle-induced infertility. In fact, it seems that individual health status as well as exercise volume, intensity and duration are effective-involved co-factors that influence the impact that exercise will promote on male fertility. Regarding these findings, it is important to study exercise different impacts in further clinical trials in order to generate preservative guidelines for exercise and also considering exercise as a treatment option in lifestyle-induced disease management.

Type 2 diabetes mellitus and the risk of abnormal spermatozoa: A Mendelian randomization study

Abnormal spermatozoa can not only reduce the fertilization rate, but also prolong the natural conception time and even increase the risk of spontaneous miscarriage. Diabetes mellitus (DM) has become a major global health problem, and its incidence continues to rise, while affecting an increasing number of men in their reproductive years. Type 2 Diabetes Mellitus (T2DM), accounting for about 85-95% of DM, is closely related to the development of sperm. However, the exact association between T2DM and abnormal spermatozoa remains unclear. Herein, we designed a Two-sample Mendelian randomization (MR) study to explore the causal association between T2DM and abnormal spermatozoa risk in European population data which come from the GWAS summary datasets. We selected 9 single nucleotide polymorphisms (SNPs) of T2DM (exposure data) as instrumental variables (IVs), and then retrieved the suitable abnormal spermatozoa genome-wide association study (GWAS) data of European from Ieu Open GWAS Project database which includes 915 cases and 209,006 control as the outcome data. Our results indicate that strict T2DM might not result in a higher risk of abnormal spermatozoa genetically in Europeans (OR: 1.017, 95% confidence interval (CI): 0.771-1.342, p=0.902). Our findings demonstrate that only T2DM may not explain the relatively higher risk of abnormal spermatozoa in men with it in Europeans. In subsequent studies, more comprehensive and larger samples need to be studied to reveal the relationship and potential mechanism between T2DM and abnormal spermatozoa.

Endocrinopathies and Male Infertility

Male infertility is approaching a concerning prevalence worldwide, and inflicts various impacts on the affected couple. The hormonal assessment is a vital component of male fertility evaluation as endocrine disorders are markedly reversible causatives of male infertility. Precise hormonal regulations are prerequisites to maintain normal male fertility parameters. The core male reproductive event, spermatogenesis, entails adequate testosterone concentration, which is produced via steroidogenesis in the Leydig cells. Physiological levels of both the gonadotropins are needed to achieve normal testicular functions. The hypothalamus-derived gonadotropin-releasing hormone (GnRH) is considered the supreme inducer of the gonadotropins and thereby the subsequent endocrine reproductive events. This hypothalamic–pituitary–gonadal (HPG) axis may be modulated by the thyroidal or adrenal axis and numerous other reproductive and nonreproductive hormones. Disruption of this fine hormonal balance and their crosstalk leads to a spectrum of endocrinopathies, inducing subfertility or infertility in men. This review article will discuss the most essential endocrinopathies associated with male factor infertility to aid precise understanding of the endocrine disruptions-mediated male infertility to encourage further research to reveal the detailed etiology of male infertility and perhaps to develop more customized therapies for endocrinopathy-induced male infertility.

Moderate-Intensity Exercise Training in Association with Insulin Promotes Heat Shock Proteins 70 and 90 Expressions in Testicular Tissue of Experimental Type 1 Diabetes

Objective

The current research was designed to analyze the effect of moderate-intensity exercise training (MEXT), solely and simultaneous with insulin, on the network between oxidative stress and Hsp70 and Hsp90 chaperones after experimental type I diabetes (DM) induction in rats.

Materials and Methods

In the experimental study, 36 mature Wistar rats were assigned into control and experimental type I DM-induced groups, and then the diabetic animals were categorized to sedentary type I DM-induced (SDM), exercise training-sole without DM (E), exercise training DM-induced (EDM), insulin-treated sedentary DM-induced (ISDM), and exercise training insulin-treated DM-induced (EIDM) groups. After 6 weeks, Johnson’s score was evaluated to analyze the spermatogenesis ratio.

Results

The Hsp70 and Hsp90 expression levels, testicular total antioxidant capacity (TAC), protein peroxidation ratio, testicular DNA fragmentation ratio, and mRNA damage were investigated. The animals in EDM and EIDM groups (solely and simultaneously) represented a significant (P<0.05) improvement in Johnson’s score, spermatogenesis, and TAC ratios versus SDM animals. Moreover, the DM-induced DNA and mRNA damage and protein peroxidation ratio were significantly (P<0.05) recovered in EDM and ISDM groups, which was more remarkable in the EIDM group. The EDM and EIDM groups exhibited significant (P<0.05) increment in Hsp70 and Hsp90 expression levels versus the control and SEDT1 animals. However, the EIDM group exhibited no significant changes compared to the control animals.

Conclusion

The EX could ameliorate the EDT1-induced detrimental impact by up-regulating Hsp70 and Hsp90 expressions. Meanwhile, it exerts potentially more effective impact, when it is considered simultaneously with insulin therapy.

Zinc and selenium supplement mitigated valproic acid-induced testis toxicity by modulating the oxidative redox balance in male rats

Valproic acid (VPA) is widely used antiepileptic agent which is associated with reproductive toxicity via impairment in oxidative redox. Zinc (Zn) and selenium (Se) are trace element with antioxidant effect that known to be essential for spermatogenesis. In the current study, the protective effect of co-administration of Zn and Se on VPA-induced reproductive toxicity in male rats was evaluated. Forty-eight male rats were divided into 8 groups of six (n=6): Control group (treated with normal saline); VPA only (250, 500, 1,000 mg/kg) group; VPA (500 mg/kg) plus Zn (2 mg/kg) group; VPA (500 mg/kg) plus Se (1.5 mg/kg) group; VPA (500 mg/kg) plus a combination of Zn and Se group; and VPA+vitamin E (20 mg/kg) group. The Animals were sacrificed after 28 days of treatment and sperm analysis was taken. Also, evaluation of oxidative stress markers including malondialdehyde (MDA), protein carbonyl (PC), glutathione (GSH) and histopathological changes were done on testis tissue. Morphological changes and a significant decrease in motility and sperm count in rats treated with VPA were observed. Also, an increase in oxidative stress marker, including MDA and PC and a decrease in GSH level was evident in VPA group. Zn and Se administration was able to protect against sperm abnormality, ameliorate the histological change in testis tissue, and suppressed the increase in oxidative stress markers induced by VPA. These results indicated that combination therapy with Zn and Se showed better an ameliorative effect than each one alone. Therefore, it can be suggested as an effective supplement for reproductive impairment in VPA-treated patient.

Why should we screen for male fertility?

An increasing number of studies show declining sperm counts; however, semen analyses are uncommon until the evaluation for infertility. Semen analysis is a safe, reliable and relatively inexpensive screening test, assessing male fertility and directing further work-up. In young men, the use of semen analysis may identify disease prior to attempted conception and result in improved fertility potential when combined with lifestyle changes, medical or surgical therapy. Furthermore, if sperm counts are significantly low, evaluation and management for genetic causes can be initiated. Our commentary outlines why screening for male infertility in young adult men may be beneficial. We discuss options for early intervention, including sperm cryopreservation, if defects in sperm parameters are identified.

Do dietary patterns and morbidities have a relationship with primary infertility among women? A study from NFHS-4 (2015-16), India

This study assessed the rate of primary infertility and its associated factors among 402,807 currently married women aged 20-49 years in India using National Family Health Survey-4 data collected in 2015-2016. Dietary patterns and selected morbidities were included as independent variables, and socioeconomic variables were considered as covariates. Bivariate and multivariate analyses were done to estimate the prevalence of primary infertility and assess its association with the selected variables, respectively. The rate of primary infertility among currently married women in India in 2015-16 was 1.9% and this was significantly associated with younger age (<35 years), higher age at marriage (≥18 years), urban residence, higher secondary or above education and poverty. The consumption of dairy products (OR = 0.79, CI = 0.73-0.86), dark green leafy vegetables (OR = 0.57, CI = 0.39-0.81) and fruit (OR = 0.88, CI = 0.77-1.01) significantly reduced the odds of primary infertility. Daily consumption of fish and aerated drinks was related to 1.06-1.21 times higher odds of primary infertility. Overweight/obesity, high blood pressure and high blood glucose levels were associated with 1.08-1.21 times elevated odds of primary infertility. Thyroid disorder (OR = 1.38, CI = 1.21-1.60), heart disease (OR = 1.17, CI = 1.16-1.19) and severe anaemia (OR = 1.24, CI = 1.00-1.53) were associated with an increased likelihood of primary infertility among women (OR 1.17-1.39, CI 1.00-1.60). The findings provide compelling evidence that primary infertility among women is related to dietary patterns and morbidities. Interventions and programmes targeting the promotion of healthy diets and lifestyles could be beneficial in addressing the issue of primary infertility among women.

Effects of ellagic acid in the testes of streptozotocin induced diabetic rats

Diabetes mellitus (DM) is a serious and common in the world health problem that leads to different complications. Changes in oxidative stress and antioxidant capacity play an important role in the pathogenesis of DM. The purpose of this study was to investigate ellagic acid (EA) treatment in diabetes induced testicular damage. In our study, 24 male Sprague Dawley rats were divided into four groups. Group 1: Control (n = 6), Group 2: EA (n = 6), Group 3: Diabet (n = 6), Group 4: Diabet + EA (n = 6). Diabetes was induced by intraperitoneal injection of streptozocin (STZ) (55 mg/kg) to group 3 and 4. EA was given 100 mg/kg/day group 2 and 4 for 35 days by oral gavage. We used that Hematoxylen-Eosin (H&E) and Johnsen's scoring to determine histological change. The terminal-deoxynucleoitidyl-transferase mediated nick end-labeling assay (TUNEL) was used for apoptosis. Oxidative stress markers were determined by qRT-PCR and immunexpression of Nrf2 was evaluated in testicular tissue. In conclusion, EA administration on the diabetes model has changed the histopathological features, apopotosis and oxidative stress marker genes in the testis and may have an effect on the reduction of diabetes induced testicular damage.

Vanillin exerts therapeutic effects against hyperglycemia-altered glucose metabolism and purinergic activities in testicular tissues of diabetic rats

Testicular dysfunctions leading to male infertility has been reported in type 2 diabetes (T2D), with glucose dysmetabolism, cholinergic and purinergic dysfunction being major contributors. In the present study, the effect of vanillin on glucose metabolism, purinergic and cholinergic dysfunctions were investigated in testicular tissues of T2D rats. Male Sprague-Dawley rats were divided into 6 groups containing 5 rats each. T2D was induced in rats by administering 10 % fructose ad libitum for 14 days followed by a single intraperitoneal injection (40 mg/kg body weight) of streptozotocin. T2D rats were orally administered with vanillin at 150 and 300 mg/kg body weight (bw). Diabetic control (DC) consisted of untreated diabetic rats, while normal control (NC) consisted of normal rats and they were administered with distilled water only. Metformin was used as the standard antidiabetic drug. After 5 weeks treatment, the rats were sacrificed, and the testes were harvested. Induction of T2D led to significantly depleted testicular levels of glutathione, glycogen content, superoxide dismutase and catalase enzyme activities, with concomitantly elevated levels of nitric oxide, malondialdehyde, acetylcholinesterase, glucose-6-phosphatase, fructose-1,6-biphophastase, glycogen phosphorylase, amylase and lipase activities. These activities and levels were significantly reversed to near normal in rats treated with both doses of vanillin as compared with metformin. These results, when taken together, suggest the therapeutic effect of vanillin against hyperglycemia-mediated metabolic dysfunctions in testes of T2D rats. This is depicted by the ability of the phenolic to attenuate oxidative imbalance, purinergic and cholinergic dysfunctions, while suppressing glucose dysmetabolism.

Nutrition, genetic variation and male fertility

Infertility affects nearly 50 million couples worldwide, with 40-50% of cases having a male factor component. It is well established that nutritional status impacts reproductive development, health and function, although the exact mechanisms have not been fully elucidated. Genetic variation that affects nutrient metabolism may impact fertility through nutrigenetic mechanisms. This review summarizes current knowledge on the role of several dietary components (vitamins A, B₁₂, C, D, E, folate, betaine, choline, calcium, iron, caffeine, fiber, sugar, dietary fat, and gluten) in male reproductive health. Evidence of gene-nutrient interactions and their potential effect on fertility is also examined. Understanding the relationship between genetic variation, nutrition and male fertility is key to developing personalized, DNA-based dietary recommendations to enhance the fertility of men who have difficulty conceiving.

Protective effects of ethyl acetate extract from Shorea roxburghii against diabetes induced testicular damage in rats

Diabetic mellitus is a chronic metabolic disorder that is associated with several complications including testicular dysfunction. This research investigated the protective action of the ethyl acetate extract from Shorea roxburghii (SRE) on diabetes induced testicular damage in rats. Diabetic rats were orally administered with SRE at doses of 100 and 400 mg/kg for 4 weeks. SRE improved the body weight gain, testes weight, testes index and increased serum concentration of testosterone. Furthermore, SRE increased the testicular antioxidant enzymes including superoxide dismutase, catalase and glutathione peroxidase. In addition, SRE ameliorated testicular inflammatory mediators such as myeloperoxidase, tumor necrosis factor alpha, interleukin 6, p38 MAPK and nuclear factor kappa B activation and decreased testicular cell apoptosis in the treated diabetic rats. SRE also raised sperm parameters after treatment of diabetic rats. Conclusively, our results suggested that SRE ameliorated diabetes induced testicular damage by inhibiting oxidative stress and inflammation.

The Role of Exercise to Reduce the Impact of Diabetes in the Seminal Quality: A Systematic Review

Background and Objectives: One of the most relevant consequences of diabetes mellitus is the temporal or complete infertility which can happen in young individuals. Therefore, the current systematic review aimed to investigate the effects of exercise to reduce the impact of Type 2 Diabetes Mellitus (T2DM) in seminal quality and related parameters. Materials and Methods: A systematic search was conducted in Pubmed and Web of Science databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines (PRISMA). The inclusion criteria were: (1) the study included at least one experimental and one comparison group, (2) the sample of the study was comprised of humans or animals with diabetes mellitus, (3) an intervention based on physical exercise was conducted, and (4) the study reported variables related to the seminal quality. Results: A total of 115 articles were identified. However, only six accomplished the inclusion and exclusion criteria. This systematic review includes a sample size of 260 participants (180 rats and 80 humans). Intervention ranged from 6 to 14 weeks, with 3–6 days per week. All interventions performed endurance training (50–70% VO₂max or maximum heart rate). Physical exercise increased sperm count, motility, and morphology, as well as improved testosterone, Luteinizing Hormone (LH), and Follicle Stimulating Hormone (FSH) levels. Moreover, physical exercise intervention reduced the percentages of sperms with negative Tubular Differentiation Index (TDI) and Spermiogenesis Index (SPI), DNA fragmentation, and also ameliorated the diabetes-induced apoptosis and improved sperm apoptosis index. Conclusions: Physical exercise could ameliorate diabetic pathological effects on sperm quality and related parameters that cause infertility or subfertility conditions. However, further homogeneous studies are needed to confirm these findings.

The association between hidradenitis suppurativa and male and female infertility: A population-based study

BACKGROUND

Endocrine and metabolic associations have been recently reported in patients with hidradenitis suppurativa (HS); however, fertility was only rarely investigated in women and not at all in men.

OBJECTIVE

To evaluate the association of HS with male and female infertility.

METHODS

A cross-sectional, matched controlled, population-based study was designed. The association between HS and male and female infertility was evaluated in patients with HS (n = 4191) and age- and gender-matched controls (n = 20 941), while utilising the Clalit Health Services databases, the largest community-based health maintenance organisation in Israel.

RESULTS

Hidradenitis suppurativa was associated with infertility in males and females over all reproductive-age groups, especially among individuals aged 36-45 years (OR 4.50, 95%CI 2.55-7.93, P < 0.001), and in female patients (OR 3.10, 95%CI 2.57-3.74, P < 0.001). After adjustment for demographic and clinical factors, the association remained significant only in females (OR 1.26 95%CI 1.04-1.55, P < 0.05).

CONCLUSION

Patients with HS are at increased risk of infertility, particularly females and patients in the 36- to 45-year age group. Physicians should take the additional physiological and psychological burden of infertility among HS patients into account, primarily among female patients at procreative age.

A closer look at the role of insulin for the regulation of male reproductive function

While insulin demonstrates to have a considerable influence on the reproductive system, there are various unanswered questions regarding its precise sites, mechanisms of action, and roles for the developing and functioning of the adult male reproductive system. Apart from its effects on glucose level, insulin has an important role in the reproductive system directly by binding on insulin and IGF receptors in the brain and testis. To date, however, the effect of insulin or its alterations on blood-testis-barrier, as an important regulator of normal spermatogenesis and fertility, has not yet been studied. This review aimed to focus on the experimental and clinical studies to describe mechanisms by which insulin affects the hypothalamic-pituitary-gonadal (HPG) axis, testicular cells, spermatozoa, and sexual behavior. Moreover, we discussed the mechanism and impact of insulin changes in type 1 (insulin deficiency along with persisted or even increased sensitivity) and 2 (insulin resistance along with increased insulin level at the early stages of disease) diabetes and obesity on the male reproductive tract.

Protective effects of carvacrol against diabetes-induced reproductive damage in male rats: Modulation of Nrf2/HO-1 signalling pathway and inhibition of Nf-kB-mediated testicular apoptosis and inflammation

Diabetes mellitus, which causes many complications, also adversely affects reproductive system in men. Studies reported that natural antioxidants are effective in reducing important complication risks caused by diabetes. Carvacrol is an antioxidant phenolic monoterpene compound with therapeutic effect in various diseases found in essential oils of aromatic plants such as pepper, wild bergamot and thyme. We aimed to investigate the effects of carvacrol on diabetes-induced reproductive damage in male rats by evaluating the Nrf2/HO-1 pathway and Nf-kB-mediated apoptosis/inflammation and spermatological parameters. For this purpose, 74 Wistar albino male rats were used. The diabetes model was performed using single-dose intraperitoneal injection of streptozotocin 55 mg/kg. Rats were fed with carvacrol 75 mg/kg/daily/gavage for 4 and 8 weeks. Rats were divided into four groups: control group, diabetic group, carvacrol group which fed with carvacrol and the diabetic group which fed with carvacrol. It was determined that carvacrol significantly decreased malondialdehyde levels, Bax,COX-2,Nf-kB protein expression levels, Bax/Bcl-2 ratio and significantly increased glutathione peroxidase, catalase activities, Bcl-2, Nrf2,HO-1 protein expression levels and it was determined that had a positive effect on spermatological parameters. In conclusion, the negative effects of diabetes in the male reproductive system can be prevented and/or reduced by giving carvacrol.

Insulin resistance and idiopathic infertility: A potential possible link

Among various health issues, infertility has been always considered as one of the major health problems. Idiopathic infertility is still a matter of debate since the underlying mechanisms stay obscure. Idiopathic infertility is related to expanded chance of metabolic syndrome components, obesity and increased risk of cardiovascular diseases. This study aimed to assess insulin resistance and serum levels of irisin as one of the adipokines in patients with idiopathic infertility. This study included 50 male patients aged 25-50 years old suffering from idiopathic infertility, together with 50 healthy individuals of matched age as controls. Patients showed significantly increased homeostasis model assessment for insulin resistance values than controls. For irisin results, idiopathic infertility patients had significantly decreased values than controls indicating the potential effect of irisin in development of insulin resistance in idiopathic infertility patients.

Effects of testicular sperm aspiration upon first cycle ICSI-ET for type 2 diabetic male patients

Male diabetes mellitus (DM) can affect erectile function and sperm quality. In severe cases, DM can lead to retrograde or no ejaculation, so testicular sperm aspiration (TESA) is combined with intracytoplasmic sperm injection (ICSI) to treat subfertility and infertility for DM couples. However, the effect of TESA upon ICSI (TESA-ICSI) for DM patients remains unclear. This research investigated the effect of TESA-ICSI on first cycle ICSI-embryo transfer (ICSI-ET) for type 2 diabetic mellitus (T2DM) patients and the potential mechanisms. The subjects consisted of 1219 male patients with azoospermia or retrograde ejaculation who were treated with TESA-ICSI from 2015.01 to 2019.11. They were classified into two groups, the T2DM group (n = 54) and non-diabetic control group (n = 1165). Sperm selection for injection was performed using motile sperm organelle morphology examination criteria. The number of available embryos and the high-quality embryo rates following a single ET as well as cleavage, fertilization, implantation, clinical pregnancy and the abortion rates were noted. Compared with the non-diabetic group, the available embryo rate (75.20 ± 26.40% vs.78.36 ± 23.25%) and high-quality embryo rate (46.49 ± 30.37% vs. 47.55 ± 28.57%) in the T2DM group were lower and the abortion rate (20.83% vs. 8.88%) was higher, but these differences were not statistically significant. There were no significant differences in clinical pregnancy, implantation, normal fertilization, and cleavage rates between the two groups. The results show that TESA for male T2DM patients does not influence the effect of ICSI. For T2DM patients with severe oligozoospermia, asthenospermia, teratozoospermia, or retrograde ejaculation that do not meet ICSI criteria, TESA-ICSI may perhaps be considered for reproductive assistance.

ABBREVIATIONS

DM: diabetes mellitus; TESA: testicular sperm aspiration; ICSI: intracytoplasmic sperm injection; ICSI-ET; ICSI-embryo transfer; LH: luteinizing hormone; mL: milliliter; TES: testosterone; FSH: follicle-stimulating hormone; P: progesterone; HCG: human chorionic gonadotropin.

Potential causes of male and female infertility in Qatar

A steady decline in the fertility rate has been observed in Qatar during the past fifty years. Therefore, infertility is considered a national priority in Qatar, a pronatalist society. This review article summarises the potential causes of infertility that are particularly prevalent in the Qatari population. The high rate of consanguinity leading to genetic abnormalities, the high incidence of metabolic disease, environmental contamination due to the rapid urbanization and oil and natural gas extraction procedures are discussed. In addition, the particular lifestyle of the Qatari population and the influence of religion and culture on sexual and reproductive behavior in an Arab/Islamic society are considered. The active response of the state of Qatar in implementing ways to mitigate the effects of these factors to protect fertility are also presented.

Experimental diabetes negatively affects the spermatogonial stem cells' self-renewal by suppressing GDNF network interactions

The present study was done to analyse the time-dependent effects of diabetes on Sertoli cells-spermatogonial stem cells' (SSCs) network interaction by focusing on glial cell line-derived neurotrophic factor (GDNF) and its special receptors, gfrα1 and c-RET as well as the Bcl-6b. In total, 40 Wistar rats were considered in; control, 20, 45 and 60 days diabetes-induced groups. An experimental diabetes was induced by STZ. The GDNF, gfrα1, c-RET and Bcl-6b expressions were evaluated. The serum level of testosterone, tubular repopulation (RI) and spermiogenesis (SPI) indices, general histological alterations, germ cells, mRNA damage, sperm count and viability were assessed. The diabetes, in a time-dependent manner, diminished mRNA and protein levels of GDNF, gfrα1, c-RET and Bcl-6b versus control group (p < .05), enhanced percentage of seminiferous tubules with negative RI, SPI, and diminished Leydig and Sertoli cells distribution, serum levels of testosterone, sperm count and viability. Finally, the number, percentage of cells and seminiferous tubules with normal mRNA content were significantly (p < .05) diminished. In conclusion, as a new data, we showed that the diabetes by inducing severe mRNA damage and suppressing GDNF, gfrα1, c-RET and Bcl-6b expressions, potentially affects the Sertoli-SSCs' network and consequently inhibits the SSCs' self-renewal process.

Clinical correlation among male infertility and overall male health: A systematic review of the literature

Purpose

Ongoing evidence has suggested the role of male factor infertility as a potential predictor of mortality and general health status. The aim of the present review is to update the current knowledge base regarding the association between male factor infertility and general health through a critical review of the literature.

Materials and Methods

A systematic review of the literature was carried out from inception to November 2019 in order to evaluate significant associations between male infertility and adverse health outcomes such as cardiovascular, oncologic, metabolic and autoimmune diseases as well as overall mortality.

Results

In all, 27 studies met inclusion criteria and were critically examined. Five studies examined male infertility and cardiovascular disease risk, 11 examined oncologic risk (e.g., overall cancer risk, testis and prostate cancer), 8 examined aggregate chronic medical diseases and 5 infertility related to incidence of mortality, for a total of 599,807 men diagnosed with any male factor infertility covering a period from 1916 to 2016.

Conclusions

A man's fertility and overall health appear to be interconnected. Therefore, a diagnosis of male infertility may allow a window into future comorbidity and/or mortality which may help guide clinical decisions and counseling. Several possible etiologies such as genetic, epigenetic, developmental, and lifestyle-based factors need to be further evaluated in order to establish the underlying mechanisms between male infertility and health.

Male Infertility and Somatic Health

Somatic health is associated with male infertility; potential links between infertility and health may arise from genetic, developmental, and lifestyle factors. Studies have explored possible connections between male infertility and oncologic, cardiovascular, metabolic, chronic, and autoimmune diseases. Male infertility also may be a predictor of hospitalization and mortality. Additional research is required to elucidate the mechanisms by which male infertility affects overall health.

Comprehensive men's health and male infertility

There is increasing evidence that male infertility may be a harbinger of comorbid medical illness. Existing studies have shed light on associations between infertility and the prevalence of cardiovascular, metabolic, and oncologic disease, along with rates of hospitalization and overall mortality. Although theorized mechanisms include genetic, developmental, and behavioral precipitants, the exact nature of these associations remains unclear and warrants further investigation.

Can Antidiabetic Drugs Improve Male Reproductive (Dys)Function Associated with Diabetes?

The alarming increase in the number of diabetic patients worldwide raises concerns regarding the impact of the disease on global health, not to mention on social and economic aspects. Furthermore, the association of this complex metabolic disorder with male reproductive impairment is worrying, mainly due to the increasing chances that young individuals, at the apex of their reproductive window, could be affected by the disease, further contributing to the disturbing decline in male fertility worldwide. The cornerstone of diabetes management is glycemic control, proven to be effective in avoiding, minimizing or preventing the appearance or development of disease-related complications. Nonetheless, the possible impact of these therapeutic interventions on male reproductive function is essentially unexplored. To address this issue, we have made a critical assessment of the literature on the effects of several antidiabetic drugs on male reproductive function. While the crucial role of insulin is clear, as shown by the recovery of reproductive impairments in insulin-deficient individuals after treatment, the same clearly does not apply to other antidiabetic strategies. In fact, there is an abundance of controversial reports, possibly related to the various study designs, experimental models and compounds used, which include biguanides, sulfonylureas, meglitinides, thiazolidinediones/glitazones, bile acid sequestrants, amylin mimetics, as well as sodiumglucose co-transporter 2 (SGLT2) inhibitors, glucagon-like peptide 1 (GLP1), α-glucosidase inhibitors and dipeptidyl peptidase 4 (DPP4) inhibitors. These aspects constitute the focus of the current review.

Oxidative Stress, NF-κB-Mediated Inflammation and Apoptosis in the Testes of Streptozotocin-Induced Diabetic Rats: Combined Protective Effects of Malaysian Propolis and Metformin

Oxidative stress, inflammation and apoptosis are major complications that trigger organ failure in diabetes mellitus (DM), and are proven to adversely affect the male reproductive system. Clinical and experimental studies have demonstrated the promising protective effects of propolis in DM and its associated systemic effects. Herein, we investigated the effect of Malaysian propolis (MP) on testicular oxidative stress, inflammation and apoptosis in diabetic rats. Further, the possibility of a complementary effect of MP with the anti-hyperglycaemic agent, metformin (Met), was studied with the idea of recommending its use in the event that Met alone is unable to contain the negative effects of DM on the male reproductive system in mind. Male Sprague-Dawley rats were either gavaged distilled water (normoglycaemic control and diabetic control groups), MP (diabetic rats on MP), Met (diabetic rats on Met) or MP+Met (diabetic rats on MP+Met), for 4 weeks. MP decreased oxidative stress by up-regulating (p < 0.05) testicular mRNA levels of nuclear factor erythroid 2-related factor 2, superoxide dismutase, catalase and glutathione peroxidase; increasing (p < 0.05) the activities of antioxidant enzymes; and decreasing (p < 0.05) lipid peroxidation in the testes and epididymis of diabetic rats. Further, MP down-regulated (p < 0.05) testicular mRNA and protein levels of pro-inflammatory mediators (nuclear factor kappa B, inducible nitric oxide synthase, tumour necrosis factor-α and interleukin (IL)-1β), decreased (p < 0.05) the nitric oxide level, and increased (p < 0.05) IL-10 mRNA and protein levels. MP also down-regulated (p < 0.05) Bax/Bcl-2, p53, casapase-8, caspase-9 and caspase-3 genes, and increased (p < 0.05) testicular germ cell proliferation. MP's effects were comparable to Met. However, the best results were achieved following co-administration of MP and Met. Therefore, we concluded that administration of the MP+Met combination better attenuates testicular oxidative stress, inflammation and apoptosis in DM, relative to MP or Met monotherapy, and may improve the fertility of males with DM.

Ameliorative effects of Lycium chinensis on male sexual dysfunction and testicular oxidative damage in streptozotocin-induced diabetic rats

The root bark of Lycium chinense (LC) has been reported to have potent antioxidant and antidiabetic properties. In the present study, we investigated the attenuative effect of LC against diabetes induced sexual dysfunction and testicular damages in animal models. Diabetic animals were treated with LC (100 and 400 mg/kg) once daily for 6 weeks. At the end of the treatment, mating behavior tests were performed and the animals were sacrificed for the determination of hormonal profile, oxidative stress indices and sperm analysis. LC administration significantly decreased blood glucose level, enhancement of the antioxidant enzyme activities, restored altered sperm characteristics and markedly improved levels of luteinizing hormone, follicle-stimulating hormone and testosterone as compared to the untreated diabetic animals. Furthermore, LC also improved sperm count, viability, motility, increased the reproductive organs weight. The results obtained indicated that L. chinense has beneficial effects in diabetes sexual dysfunction.

Periconceptional environment and the developmental origins of disease

The concept emerging from Professor David Barker’s seminal research on the developmental origins of later-life disease has progressed in many directions since it was first published. One critical question being when during gestation might environment alter the developmental programme with such enduring consequences. Here, we review the growing consensus from clinical and animal research that the period around conception, embracing gamete maturation and early embryogenesis might be the most vulnerable period. We focus on four types of environmental exposure shown to modify periconceptional reproduction and offspring development and health: maternal overnutrition and obesity; maternal undernutrition; paternal diet and health; and assisted reproductive technology. These conditions may act through diverse epigenetic, cellular and physiological mechanisms to alter gene expression and cellular signalling and function in the conceptus affecting offspring growth and metabolism leading to increased risk for cardiometabolic and neurological disease in later life.

Gliclazide alone or in combination with atorvastatin ameliorated reproductive damage in streptozotocin-induced type 2 diabetic male rats

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High-fat diet/STZ-induced T2DM caused severe damage in rat male reproductive system.

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ATV treatment slightly improved the reproductive functions.

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GLZ treatment strongly ameliorated spermatogenesis as well as testicular structure.

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ATV/GLZ combination treatment improved sperm morphology and testes structure.

Objectives

Type 2 diabetes (T2DM) is one of the most serious challenges of the 21th century with life-threatening complications and excessive health care costs. In diabetic patients, the main goal in T2DM treatment is the regulation of both blood glucose and lipid levels. For that, Gliclazide (GLZ), an oral antidiabetic, and Atorvastatin (ATV), a lipid lowering agent, are widely used drugs as combination. Diabetes has been reported severe impacts on male reproductive system; however, data obtained about ATV and GLZ treatment alone or in combination are conflicted or insufficient. Herein the effects of ATV and GLZ on male reproductive system in type 2 diabetic male rats have been investigated in the present study.

Methods

T2DM was induced by high-fat diet and single injection of streptozotocin (STZ) (35 mg/kg) in young adult male Sprague-Dawley rats. The diabetic rats were given ATV (10 mg/kg), GLZ (10 mg/kg) and ATV/GLZ (1:1, 10 mg/kg) combination by oral gavage for 28 days. The hormone levels were determined in the cardiac blood samples; and the histopathological and ultrastructural analyses were conducted in the testicular tissues and epididymal sperms.

Results

It was observed that diabetes had severe effects on testicular tissue and spermatogenesis. ATV treatment did not affect sperm count and testes structure (p > 0.05), however ameliorated sperm morphology (p < 0.05). GLZ treatment increased sperm count, and improved sperm morphology, testes structure and spermatogenesis (p < 0.05). ATV/GLZ combination treatment enhanced sperm morphology and improved testicular structure (p < 0.05) while did not affect sperm count (p > 0.05).

Conclusion

GLZ treatment regenerated testicular damage and sperm parameters whether alone or in combination with ATV in diabetic rats without affecting hypothalamic-pituitary-gonadal axis.

Seminal Oxidative Stress Markers, Calcium, Magnesium, and Semen Profile of Infertile Diabetic and Nondiabetic Nigerian Men

Context

Oxidative stress, vitamin, and macroelement deficiencies have been implicated in male infertility. It is unknown if diabetes mellitus with its attendant increased oxidative stress makes the seminal quality of the diabetic infertile men worse compared to their nondiabetic counterparts.

Aims

The study investigated semen parameters, seminal plasma calcium, magnesium, Vitamins C and E, and total antioxidant capacity (TAC) in diabetic and nondiabetic infertile men.

Settings and Design

This was a cross-sectional study involving 30 infertile men with type 2 diabetes, 30 infertile nondiabetic men and 30 fertile men.

Subjects and Methods

Fasting plasma glucose, glycated hemoglobin, seminal plasma calcium, magnesium, TAC, Vitamin C, Vitamin E, semen analysis, and cultures carried out using the standard procedures.

Statistical Analysis Used

Data were analyzed by the analysis of variance and Student's t-test; the level of significance was set at P < 0.05.

Results

Both infertile groups had significantly lower (P < 0.0001) sperm count, percentage motility, TAC, Vitamin E and C, magnesium and calcium when compared to the fertile group. However, there was no statistically significant difference (P > 0.05) in the mean values of these parameters among the two infertile groups. The infertile men had a significantly higher (P = 0.034) frequency of bacterial isolates compared to the fertile men. Staphylococcus aureus was the most frequent organism isolated.

Conclusions

Seminal calcium, magnesium, TAC, and Vitamin E and C were lower in both infertile diabetic and nondiabetic men as compared to that of fertile men, but the levels of these analytes were comparable in the infertile diabetic and nondiabetic men.

Risk of metabolic disorders in childless men: a population-based cohort study

OBJECTIVE

To study whether male childlessness is associated with an increased risk of metabolic disorders such as metabolic syndrome (MetS) and diabetes.

DESIGN

A population-based cohort study.

SETTING

Not applicable.

PARTICIPANTS

2572 men from the population-based Malmö Diet and Cancer Cardiovascular Cohort.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

From cross-sectional analyses, main outcome measures were ORs and 95% CIs for MetS and diabetes among childless men. In prospective analyses, HRs and 95% CI for diabetes among childless men.

RESULTS

At baseline, in men with a mean age of 57 years, the prevalence of MetS was 26% and 22% among childless men and fathers, respectively. Similarly, we observed a higher prevalence of diabetes of 11% among childless men compared with 5% among fathers. In the cross-sectional adjusted analyses, childless men had a higher risk of MetS and diabetes, with ORs of 1.22 (95% CI 0.87 to 1.72) and 2.12 (95% CI 1.34 to 3.36) compared with fathers. In the prospective analysis, during a mean follow-up of 18.3 years, we did not see any increase in diabetes risk among childless men (HR 1.02 (0.76 to 1.37)).

CONCLUSION

This study provides evidence of an association between male childlessness and a higher risk of MetS and diabetes. However, as these associations were found in cross-sectional analyses, reverse causation cannot be excluded.

High Blood Pressure Is a Highly Prevalent but Unrecognised Condition in Primary Infertile Men: Results of a Cross-sectional Study

BACKGROUND

Although most of the components related to metabolic syndrome were shown to have a detrimental effect on male fertility, the effects of high blood pressure (HBP) have been partially analysed.

OBJECTIVE

To investigate the prevalence and impact of hypertension on clinical and semen parameters in a cohort of white European men presenting for couple's infertility at a single tertiary referral academic centre.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional study was performed including analysis of data from 2185 primary infertile men. Comorbidities were scored with Charlson Comorbidity Index (CCI; categorised 0 vs ≥1). HBP was defined as blood pressure ≥140/90mmHg. Semen analyses followed the 2010 World Health Organization reference criteria.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Descriptive statistics and logistic regression analyses tested the association among semen parameters, clinical characteristics, and HBP.

RESULTS AND LIMITATIONS

Overall, HBP was found in 6.8% of infertile patients and in 3.6% of age-comparable men without known fertility problems. Of 148 patients, 85 (58%) were either unaware of their HBP or not adequately medically-controlled. +HBP men were older (median age [interquartile range], 37 [33-40] vs 39 [36-44] yr; p<0.001), had higher CCI scores (X₂=25.6; p<0.001), higher BMI (25.1 [23.3-27.3] vs 26.8 [24.9-29.4]; p<0.001), and a waist circumference >102cm in a greater proportion of individuals (41% vs 23%; X₂=4.68 p<0.05) than -HBP men. Hypertensive and normotensive men did not differ in terms of hormonal milieu and semen parameters. Patients did not differ in terms of HPB rates according to oligozoospermia, asthenozoospermia, and teratozoospermia status. The lack of a real control group represents the main limitation of the study.

CONCLUSIONS

Hypertension and unrecognised or not adequately controlled HBP are highly prevalent among white European primary infertile men. Hypertension per se did not have an impact on hormonal and semen parameters.

PATIENT SUMMARY

Because of its effects in terms of overall prospective men's health, high blood pressure must be comprehensively considered over the basic work-up of every infertile man in the outpatient clinic setting.

High regenerative capacity of the liver and irreversible injury of male reproductive system in carbon tetrachloride-induced liver fibrosis rat model

BACKGROUND

Liver fibrosis (LF) is a chronic disease, associated with many collateral diseases including reproductive dysfunction. Although the normal liver has a large regenerative capacity the complications of LF could be severe and irreversible. Hormone and sex-related issues of LF development and interactions with male reproductive have not been finally studied. The aim was to study the reproductive function of male rats in experimental CCl4-induced liver fibrosis rat model, and the capability for restoration of both the liver and male reproduction system.

MATERIALS

Studies were conducted on 20 3-month old Wistar male rats. The experimental animals were injected with freshly prepared 50% olive oil solution of carbohydrate tetrachloride (CCl4). On the 8th week after injection we noted the manifestations of liver fibrosis. The rats were left to self-healing of the liver for 8 weeks. All male rats underwent ultrasound and biopsy of the liver and testes on the 8th and 16th weeks. The male rats were mated with healthy females before CCl4 injection, after modeling LF on the 8th week, and after self-healing of the liver. Pregnancy was monitored on ultrasound.

RESULTS

On the 8th week of experiment we observed ultrasound manifestation of advanced liver fibrosis, including hepatosplenomegaly, portal hypertension. Ultrasound exam of the rat testes showed testicular degeneration, hydrocele, fibrosis, scarring, petrifications, size reduction, and restriction of testicular descent; testes size decreased from 1.24 ± 0.62 ml to 0.61 ± 0.13, p < 0.01. Liver histology showed granular dystrophy of hepatocytes, necrotic areas, lipid inclusions in parenchyma. Rats with liver fibrosis demonstrated severe injury of the reproductive system and altering of fertility: the offspring of male rats with advanced LF was 4.71 ± 0.53 born alive vs 9.55 ± 0.47 born from mating with healthy males, p < 0.001. Eight weeks after last CCl4 injection, we revealed signs of liver regeneration, significant recovery of its structure. The ALT and AST levels significantly decreased and reached background measurements. As a result of the second interbreeding after liver self-healing no significant difference was found vs previous mating.

CONCLUSION

Carbohydrate tetrachloride induces injury of liver parenchyma evoking fast and severe liver fibrosis, and is associated with irreversible structural and functional changes in testes, reducing fertility, decreasing potential pregnancy rate, and affecting its development. Liver showed high potential to regenerate, however the self-restoring after liver fibrosis was not accompanied with recovery of the reproductive system.