Effects of resveratrol on reducing spermatogenic dysfunction caused by high-intensity exercise

Effect of resveratrol on spermatogenesis in breeding boars and the proteomic analysis for testes

Effect of resveratrol (RSV) on spermatogenesis and the mechanism of resveratrol in promoting spermatogenesis of breeding boars was explored by feeding sexually mature Duroc boars with normal diet and 20 mg/kg resveratrol diet for 14 days to the control group and experimental group, respectively. Semen volume, sperm density, motility, viability and abnormality rate were analyzed on day 0, 7, and 14. Blood samples were collected, and levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T) in serum were analyzed. On day 14, the testis tissue was collected for antioxidant and proteomics analysis etc. The semen volume, sperm density, motility, and viability of the experimental group and the contents of serum FSH, LH, T and plasma SOD activity were significantly higher than those in the control group. However, the serum IL-6, TNF-α and plasma MDA were remarkably lower in experimental group. The above results showed that resveratrol can simulate spermatogenesis in breeding boars. Proteomic results demonstrated that three differentially expressed proteins (DEPs) were up-regulated and 12 DEPs were down-regulated; ODF1, calmodulin, Cabs1, and Hp were involved in spermatogenesis; and the main enriched metabolic pathway is steroid hormone synthesis pathway. Therefore, the improvement in sperm quality by resveratrol may be achieved by regulating the changes in outer dense fiber 1, calmodulin, spermatid specific 1, and haptoglobin expression and steroid synthesis pathway.

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.

Reprotoxic Impact of Environment, Diet, and Behavior

Reproductive health is progressively declining due to multiples endogenous and exogenous factors, such as environmental contaminants, diet and behavior. Accumulated evidences confirm that fertility and reproductive function have been adversely affected by exposure to chemical contaminants released in the environment. Today, the impact of diet and behavior on reproductive processes is also receiving special attention from the scientific community. Indeed, a close relationship between diet and fertility has been proven. Furthermore, a combination of unhealthy behavior, such as exposure to hazardous compounds and stress factors, poses living organisms at higher risk of reprotoxic effects. In particular, it has been described that poor life behaviors are associated with reduced male and female fertility due to decreased gamete quality and function. Most of the erroneous behaviors are, furthermore, a source of oxidative stress that, leading to epigenetic alterations, results in an impaired reproductive fitness. This review reports the detrimental impact of the most common environmental chemical stressors, diet, and behavior on reproductive functionality and success. Although clear evidences are still scarce, reassuring data are provided that a healthy diet and reverting unhealthy lifestyles may be of help to recover physiological reproductive conditions.

The Role of Selected Natural Biomolecules in Sperm Production and Functionality

Emerging evidence from in vivo as well as in vitro studies indicates that natural biomolecules may play important roles in the prevention or management of a wide array of chronic diseases. Furthermore, the use of natural compounds in the treatment of male sub- or infertility has been proposed as a potential alternative to conventional therapeutic options. As such, we aimed to evaluate the effects of selected natural biomolecules on the sperm production, structural integrity, and functional activity. At the same time, we reviewed their possible beneficial or adverse effects on male reproductive health. Using relevant keywords, a literature search was performed to collect currently available information regarding molecular mechanisms by which selected natural biomolecules exhibit their biological effects in the context of male reproductive dysfunction. Evidence gathered from clinical trials, in vitro experiments and in vivo studies suggest that the selected natural compounds affect key targets related to sperm mitochondrial metabolism and motion behavior, oxidative stress, inflammation, DNA integrity and cell death. The majority of reports emphasize on ameliorative, stimulating and protective effects of natural biomolecules on the sperm function. Nevertheless, possible adverse and toxic behavior of natural compounds has been indicated as well, pointing out to a possible dose-dependent impact of natural biomolecules on the sperm survival and functionality. As such, further research leading to a deeper understanding of the beneficial or adverse roles of natural compounds is necessary before these can be employed for the management of male reproductive dysfunction.

Responses and coping methods of different testicular cell types to heat stress: overview and perspectives

To facilitate temperature adjustments, the testicles are located outside the body cavity. In most mammals, the temperature of the testes is lower than the body temperature to ensure the normal progression of spermatogenesis. Rising temperatures affect spermatogenesis and eventually lead to a decline in male fertility or even infertility. However, the testes are composed of different cell types, including spermatogonial stem cells (SSCs), spermatocytes, spermatozoa, Leydig cells, and Sertoli cells, which have different cellular responses to heat stress. Recent studies have shown that using different drugs can relieve heat stress-induced reproductive damage by regulating different signaling pathways. Here, we review the mechanisms by which heat stress damages different cells in testes and possible treatments.

Effect of resveratrol intervention on renal pathological injury and spermatogenesis in type 2 diabetic mice

BACKGROUND

Type 2 diabetes (T2D) is a clinically common cardiovascular disease that can lead to kidney damage and adversely affect male fertility and sperm quality. Resveratrol (Res) is a natural product that has a wide range of effects in animals and cell models.

OBJECTIVE

This research is designed to observe the effect of resveratrol (Res) intervention on renal pathologic injury and spermatogenesis in mice with type 2 diabetes (T2D).

METHODS

Sixty healthy male SD mice without specific pathogens (SPF grade) were selected, and numbered by statistical software to randomize into control group (CG; n=20), model group (MG; n=20) and research group (RG; n=20). Mice in CG were given regular diet, while those in MG and RG were fed with high fat diet. Subsequently, RG was given Res intervention while MG received no treatment. Biochemical indexes [triglyceride (TG), total cholesterol (TC), fasting blood glucose (FBG), 24-hour urinary albumin excretion rate (24h-UAER)] of mice in the three groups before and after intervention were observed and recorded. The effect of Res on oxidative stress, kidney histopathological structure, spermatogenic function, sperm density and viability of mice, as well as spermatogenic cell cycle of testis were determined.

RESULTS

Res reduced hyperlipidemia and hyperglycemia in T2D mice. By reducing malondialdehyde (MDA) and increasing superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), Res relieved oxidative stress and alleviated kidney tissue damage. In addition, Res improved the spermatogenic function of T2D mice by increasing the sperm density and survival rate and restoring the percentage of spermatogenic cells at all levels.

CONCLUSIONS

Res intervention in T2D mice can reduce kidney tissue damage, lower blood glucose (BG), and improve spermatogenic function by increasing sperm density and restoring the percentage of spermatogenic cells at all levels.

Metabolomics analysis reveals metabolic changes associated with trans-resveratrol treatment in experimental cryptorchidism mice

This study aimed to analyse global metabolomic changes associated with trans-resveratrol (RSV) treatment in mice with cryptorchidism using untargeted metabolomics. Cryptorchidism was established surgically in Kunming mice, which were then treated with 20µg g-1 day-1, s.c., RSV for 35 consecutive days. Typical manifestations of spermatogenesis arrest were seen in mice with cryptorchidism, and RSV treatment for 35 days restored spermatogenesis. Liquid chromatography-tandem mass spectrometry was used to profile the metabolome of testes from mice in the control (non-cryptorchid, untreated), cryptorchid and RSV-treated cryptorchid groups. In all, 1386 and 179 differential metabolites were detected in the positive and negative modes respectively. Seven and six potential biomarkers were screened for spermatogenesis arrest and restoration respectively. Pathway analysis showed changes in 197 metabolic pathways. The hexosamine biosynthesis pathway was inhibited in the cryptorchid group, which probably resulted in a decrease in the end product, uridine diphosphate N-acetylglucosamine (UDP-GlcNAc). Immunoblot analysis showed that total testicular protein O-linked β-N-acetylglucosamine glycosylation was related to spermatogenesis arrest, further indicating a decrease in UDP-GlcNAc in the cryptorchid group. Thus, untargeted metabolomics revealed the biochemical pathways associated with the restoration of metabolic status in the cryptorchid group following RSV treatment and the findings could be used to monitor the response to RSV treatment. This study provides a meaningful foundation for the future clinical application of RSV in the treatment of spermatogenesis dysfunction.

Oyster peptide prevents the occurrence of exercise-hypogonadal male condition by improving the function of pituitary gonadal axis in male rats

This study evaluates the protective role of oyster peptide (OP) on the occurrence of Exercise-Hypogonadal Male Condition. Male rats were given heavy-load swimming training and / or OP was supplemented for 6 consecutive weeks. After heavy-load training, sperm count, sperm viability and sperm motility in epididymis, testosterone in serum and testis, glutathione peroxidase (GSH-px) and androgen receptor (AR) in testis and mating times were remarkably decreased, malondialdehyde (MDA), capture latency and mating latency were significantly increased, mRNA expression of steroidogenic acute regulatory (StAR) and P450 cholesterol side-chain cleavage enzyme (P450scc) were obviously down-regulated, but serum follicle-stimulating hormone (FSH) and luteinising hormone (LH) were not statistically changed. Conversely, when OP was supplemented at heavy-load training, sperm count, sperm viability and sperm motility in epididymis, serum FSH, LH, testosterone, GSH-px, superoxide dismutase (SOD), testosterone, AR in testis and mating times were dramatically increased, while testicular MDA, capture latency and mating latency were significantly decreased, and mRNA expression of StAR, StARD7, P450scc and 3β-hydroxysteroid dehydrogenase (3β-HSD) were significantly up-regulated. In conclusion, heavy-load training causes testicular spermatogenic and steroidogenic disorders by enhancing the generation of reactive oxygen species (ROS), which can be protected by the co-administration of OP by enhancing the function of pituitary gonad axis and lowering ROS generation.

Polyphenols in Farm Animals: Source of Reproductive Gain or Waste?

Reproduction is a complex process that is substantially affected by environmental cues, specifically feed/diet and its components. Farm animals as herbivorous animals are exposed to a large amount of polyphenols present in their natural feeding system, in alternative feed resources (shrubs, trees, and agro-industrial byproducts), and in polyphenol-enriched additives. Such exposure has increased because of the well-known antioxidant properties of polyphenols. However, to date, the argumentation around the impacts of polyphenols on reproductive events is debatable. Accordingly, the intensive inclusion of polyphenols in the diets of breeding animals and in media for assisted reproductive techniques needs further investigation, avoiding any source of reproductive waste and achieving maximum benefits. This review illustrates recent findings connecting dietary polyphenols consumption from different sources (conventional and unconventional feeds) with the reproductive performance of farm animals, underpinned by the findings of in vitro studies in this field. This update will help in formulating proper diets, optimizing the introduction of new plant species, and feed additives for improving reproductive function, avoiding possible reproductive wastes and maximizing possible benefits.

The Effect of Macronutrients on Reproductive Hormones in Overweight and Obese Men: A Pilot Study

Hypogonadal obese men find it difficult to lose weight. We investigated whether the modification of macronutrient intake can alter testosterone levels independently of the body mass index. Fasted overweight or obese fertile men were asked to consume meals of polyunsaturated fats (PUFA), monounsaturated fats (MUFA), refined carbohydrates (CHO, orange juice, OJ), whey and egg albumin and mixed meals of PUFA and CHO, PUFA and egg albumin, and CHO and egg albumin. Blood was collected at fasting, then hourly for 5 h and analysed to determine the levels of testosterone and other hormones. We found PUFA and MUFA or a mixed meal of PUFA and CHO significantly reduced serum testosterone production to a similar degree over a 5 h period. PUFA decreased serum testosterone levels by 3.2 nmol/L after 1 h compared to baseline (p = 0.023), with this suppression remaining significant up to 5 h postprandially (2.1 nmol/L; p = 0.012). The net overall testosterone levels were reduced by approximately 10 nmol/L × h by PUFA, MUFA and PUFA combined with CHO. CHO alone had little effect on testosterone levels, whereas egg albumin was able to increase them (7.4 cf 2.0 nmol/L × h). Therefore, for men wishing to optimize their testosterone levels, it may be wise to avoid a high fat intake, drink liquids such as water or OJ or even consider fasting. ANZCTR, Australia; ACTRN12617001034325.

The effects of resveratrol on metabolic status in patients with type 2 diabetes mellitus and coronary heart disease

This study was performed to investigate the effects of resveratrol on metabolic status in patients with type 2 diabetes mellitus (T2DM) and coronary heart disease (CHD). This randomized, double-blind, placebo-controlled trial was performed with 56 patients having T2DM and CHD. The patients were randomly divided into two groups to receive either 500 mg resveratrol per day (n = 28) or placebo (n = 28) for 4 weeks. Resveratrol reduced fasting glucose (β-10.04 mg dL^-1; 95% CI, -18.23, -1.86; P = 0.01), insulin (β-1.09 μIU mL^-1; 95% CI, -1.93, -0.24; P = 0.01) and insulin resistance (β-0.48; 95% CI, -0.76, -0.21; P = 0.001) and significantly increased insulin sensitivity (β 0.006; 95% CI, 0.001, 0.01; P = 0.02) when compared with the placebo. Resveratrol also significantly increased HDL-cholesterol levels (β 3.38 mg dL^-1; 95% CI, 1.72, 5.05; P < 0.001) and significantly decreased the total-/HDL-cholesterol ratio (β-0.36; 95% CI, -0.59, -0.13; P = 0.002) when compared with the placebo. Additionally, resveratrol caused a significant increase in total antioxidant capacity (TAC) (β 58.88 mmol L^-1; 95% CI, 17.33, 100.44; P = 0.006) and a significant reduction in malondialdehyde (MDA) levels (β-0.21 μmol L^-1; 95% CI, -0.41, -0.005; P = 0.04) when compared with the placebo. Resveratrol upregulated PPAR-γ (P = 0.01) and sirtuin 1 (SIRT1) (P = 0.01) in the peripheral blood mononuclear cells (PBMCs) of T2DM patients with CHD. Resveratrol supplementation did not have any effect on inflammatory markers. Four-week supplementation of resveratrol in patients with T2DM and CHD had beneficial effects on glycemic control, HDL-cholesterol levels, the total-/HDL-cholesterol ratio, TAC and MDA levels. Resveratrol also upregulated PPAR-γ and SIRT1 in the PBMCs of T2DM patients with CHD.