Curcumin ameliorates high‑fat diet‑induced spermatogenesis dysfunction

Effects of Physical Activity on Fertility Parameters: A Meta-Analysis of Randomized Controlled Trials

PURPOSE

Augmented adiposity may negatively impact sexual sphere through its metabolic effects and its detrimental impact on reproductive hormones. Moreover, a dysregulated metabolic pathway may promote apoptosis among spermatogenic cells. Based on these premises, a relation between weights loss and ameliorate semen parameters seems beneficial. To investigate if physical activity may affect semen parameters and fertility rate, a systematic literature search on major dataset has been performed.

MATERIALS AND METHODS

The search terms included: "Assisted reproduction therapies," "fertility," "semen parameters," "sperm parameters," and "physical activity." This analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines and it was registered on PROSPERO (CRD42023384471). A total of 47 studies have been identified; 1 reference has been eliminated after duplication check. After preliminary screening 32 papers have been excluded. Considering the exclusion criteria, 15 full-text articles were evaluated for eligibility. After a full-text review, six studies published during a span of eight years (2014-2022) have been included in the meta-analysis. Semen parameters, pregnancy and birth rates were investigated. The revised Cochrane risk of bias tool (Rob2) has been used to check the risk of bias.

RESULTS

The number of patients enrolled in studies ranges from 17 to 521; in the end, a total of 1,637 patients have been enrolled in the study. Fertility parameters investigated were semen quality parameters and pregnancy rates and live births. A statistically significant relationship between physical exercise and sperm concentration (p=0.02), total sperm motility (p<0.01), total sperm count (p<0.01), normal morphology (p<0.01) has been established. Moreover, the study registered a statistically significant association within physical activity and total pregnancy rate (p<0.01) and live birth rate (p<0.01).

CONCLUSIONS

We demonstrated that physical activity is significantly associated with amelioration of semen parameters and may be crucial in improving or even reverting male infertility.

Pathophysiology of obesity-related infertility and its prevention and treatment by potential phytotherapeutics

BACKGROUND

Obesity is a complex multifactorial disease in which the accumulation of excess body fat has adverse health effects, as it can increase the risk of several problems, including infertility, in both men and women. Obesity and infertility have risen together in recent years. Against this background, the present review aims to highlight the impact of obesity on infertility and the underlying pathophysiology of obesity-related infertility (ORI) in men and women, and to provide readers with knowledge of current trends in the effective development of phytotherapeutics for its treatment.

METHODS

We thoroughly searched in PubMed, MEDLINE, Scopus, EMBASE, and Google Scholar to find all relevant papers on ORI and the therapeutic effects of phytotherapeutics on ORI in men and women.

RESULTS

The extensive search of the available literature revealed that obesity affects reproductive function through several complex mechanisms such as hyperlipidaemia, hyperinsulinaemia, hyperandrogenism, increased body mass index, disruption of the hormonal milieu, systemic inflammation, oxidative stress, alterations in epigenetics and dysbiosis. On the other hand, several studies reported that phytotherapeutics has a broad therapeutic spectrum of action by improving sex hormone homeostasis, ovarian dysfunction, menstrual cycle and inhibiting ovarian hyperplasia, as well as down-regulating ovarian apoptosis, inflammation and oxidative stress, and controlling metabolic dysfunction in obese women. Male infertility is also addressed by phytotherapeutics by suppressing lipogenesis, increasing testosterone, 3β-HSD and 17β-HSD levels, improving sperm parameters and attenuating testicular dyslipidaemia, oxidative stress, inflammation and germ cell apoptosis.

CONCLUSIONS

In the present review, we discussed the effects of obesity on reproductive dysfunction in men and women and the underlying pathophysiology of ORI. In addition, the therapeutic effect of phytotherapeutics against ORI was highlighted.

Nanomicelle curcumin-induced testicular toxicity: Implications for altered mitochondrial biogenesis and mitophagy following redox imbalance

The purpose of this study was to examine the effects of nano-micelle curcumin (NMC)-induced redox imbalance on mitochondrial biogenesis and mitophagy. For this purpose, 24 mature male Wistar rats were divided into control and NMC-received groups (7.5, 15, and 30 mg/kg) groups. After 48 days, the Nrf1, Nrf2, and SOD (Cu/Zn) expression levels, as well as GSH/GSSG, NADP+ /NADPH relative balances (elements involved in redox homeostasis) were analyzed. Moreover, to explore the effect of NMC on mitochondrial biogenesis, the expression levels of Mfn1, Mfn2, OPA1, Fis1, and Drp1 were investigated. Finally, the expression levels of Parkin/PARK and PINK (genes involved in mitochondrial quality control), as well as LC3-I/II (mitophagy marker), were analyzed. Observations showed that NMC, dose-dependently, altered GSH/GSSG, NADP+ /NADPH relative balances, suppressed SOD expression and diminished its biochemical level, and repressed Nrf1 and Nrf2 expression levels. Moreover, it could change the Mfn1, Mfn2, OPA1, Fis1, and Drp1 expression pattern and stimulate the Parkin/PARK and PINK as well as LC3-I/II expression levels, dose-dependently. In conclusion, chronic and high-dose NMC is able to suppress the redox capacity by down-regulating the Nrf1 and Nrf2 expression. Finally, at high-dose levels, it is able to trigger mitophagy signaling in the testicles.

Curcumin Remedies Testicular Function and Spermatogenesis in Male Mice with Low-Carbohydrate-Diet-Induced Metabolic Dysfunction

Increasing reports on the significance of dietary patterns in reproduction have arisen from both animal and human studies, suggesting an interactive association between nutrition and male fertility. The aim of this study was to investigate the effects of curcumin supplementation on low-carbohydrate-diet-induced metabolic dysfunction, testicular antioxidant capacity, apoptosis, inflammation and spermatogenesis in male mice. Male C57BL/6 mice were fed a normal diet (AIN-93M group, n = 12) and a low-carbohydrate diet for 12 weeks (LC group, fed with low-carbohydrate diet, n = 48), and mice randomly chosen from the LC group were later fed their original diet (LC group, n = 12). This diet was changed to AIN-93M feed (LC/AIN-93M group, n = 12), a ketogenic diet (LC/KD group, n = 12), or a ketogenic diet treated with curcumin supplementation for the final 6 weeks (LC/KDCu group, n = 12). A poor sperm morphology and mean testicular biopsy score (MTBS) were observed in the LC and LC/KD groups, but they were eliminated by the normal diet or ketogenic diet with curcumin. The LC group exhibited a lower testicular testosterone level and a lower 17β-HSD activity and protein expression. This also enhanced apoptosis protein expressions in testis tissue, including Bax/BCl₂, cleaved caspase 3, PARP and NF-κB. Meanwhile, we found a statistically significant increase in lipid peroxidation and decreased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase levels in the LC group. Our study indicated that a replacement of a normal diet or ketogenic diet supplemented with curcumin attenuated poor semen quality and reduced testosterone levels by the LC diet by reducing oxidative stress.

Comparative Evaluation of the Parameters of Sperm Apoptosis of Young and Middle-Aged Men by Flow Cytometry

A comparative analysis of the parameters characterizing sperm apoptosis of young (27-42 years) and middle-aged (44-51 years) men was performed by flow cytometry. Irrespective of age, activity of caspase-3 and p53-mediated controlling the transmission of apoptogenic signal transmission in gametes remained stable with the formation of germ cells with delayed (p<0.05) cell death according to the Annexin V-FITC⁺PI- criterion (predominantly in middle-aged men). Inhibition of the transmission of a proapoptogenic stimulus mediated by membrane cell death receptors (FAS) was also observed in this group. Comparison of indicators of sperm apoptosis showed age-related features of cell death, in particular, inhibition of membrane reception triggering FAS-dependent apoptosis, which is associated with insufficient phosphatidylserine production in middle-aged men, excessive life cycle duration, and aging of spermatozoa.

Irisin alleviates obesity-related spermatogenesis dysfunction via the regulation of the AMPKα signalling pathway

BACKGROUND

Infertility is a common complication in obese men. Oxidative stress and testicular apoptosis play critical roles in obesity-induced spermatogenesis dysfunction. It has been reported that irisin, an exercise-induced myokine, may attenuate oxidative damage and testicular apoptosis in several diseases; however, its role in obesity-induced spermatogenesis dysfunction remains unclear. The purpose of this study was to investigate the role and underlying mechanism of irisin in obesity-induced dysfunction of spermatogenesis.

METHODS

Male mice were fed a high-fat diet (HFD) for 24 weeks to establish a model of obesity-induced spermatogenesis dysfunction. To explore the effects of irisin, mice were subcutaneously infused with recombinant irisin for 8 weeks beginning at 16 weeks after starting a HFD. To confirm the role of AMP-activated protein kinase α (AMPKα), AMPKα-deficient mice were used.

RESULTS

The data showed decreased serum irisin levels in obese patients, which was negatively correlated with sperm count and progressive motility. Irisin was downregulated in the plasma and testes of obese mice. Supplementation with irisin protected against HFD-induced spermatogenesis dysfunction and increased testosterone levels in mice. HFD-induced oxidative stress, endoplasmic reticulum (ER) stress and testicular apoptosis were largely attenuated by irisin treatment. Mechanistically, we identified that irisin activated the AMPKα signalling pathway. With AMPKα depletion, we found that the protective effects of irisin on spermatogenesis dysfunction were abolished in vivo and in vitro.

CONCLUSIONS

In conclusion, we found that irisin alleviated obesity-related spermatogenesis dysfunction via activation of the AMPKα signalling pathway. Based on these findings, we hypothesized that irisin is a potential therapeutic agent against obesity-related spermatogenesis dysfunction.

Moringa oleifera ethanolic extract ameliorates the testicular dysfunction resulted from HFD-induced obesity rat model

In this study, we estimated the protective role of Moringa oleifera leaf ethanolic extract (MOLE) against obesity-associated testicular dysfunction. Fifty male albino rats were randomly assigned to five groups (n = 10): Group I (basal diet), group II (basal diet plus MOLE orally), group III (high-fat diet-HFD), group IV (HFD plus oral MOLE) and group V (HFD for 8 weeks followed by a basal diet plus oral MOLE for 6 weeks). The study duration extended for 14 weeks. Serum collected to investigate testosterone, FSH and LH levels. Testicular tissues were used to determine levels of SOD, glutathione, catalase and malondialdehyde. Semen was collected to estimate its quality (morphology, motility and concentration). Morphological changes in the testis were investigated by histopathological and immunohistochemical techniques. Compared with both control treatment and MOLE treatment, serum testosterone, FSH, LH, testicular enzymatic catalase, SOD, GSH, survivin immunoreactivity, sperm quality and testicular weight were all significantly decreased in rats treated with HFD, while there were significant increases in testicular malondialdehyde and caspase-3 immunoreactivity. MOLE improved all harmful effects of HFD. Improvements were more pronounced in the protected (G 4) than the treated (G 5) group. MOLE could be a potential solution for obesity-associated fertility problem.

Voluntary exercise improves sperm parameters in high fat diet receiving rats through alteration in testicular oxidative stress, mir-34a/SIRT1/p53 and apoptosis

OBJECTIVES

High fat diet can lead to testicular structural and functional disturbances, spermatogenesis disorders as well as infertility. So, the present investigation was proposed to clarify whether voluntary exercise could prevent high fat diet induced reproductive complications in rats through testicular stress oxidative and apoptosis.

METHODS

Forty male Wistar rats were randomly divided into four groups; control (C), voluntary exercise (VE), high fat diet (HFD) and high fat diet and voluntary exercise (VE + HFD) groups. The rats in the VE and VE + HFD groups were accommodated in apart cages that had running wheels and the running distance was assessed daily for 10 weeks. In VE + HFD group, animals were fed with HFD for five weeks before commencing exercise. The sperm parameters, the expressions of testicular miR-34a gene, and P53 and SIRT1 proteins as well as testicular apoptosis were analyzed in all groups.

RESULTS

The results indicated that voluntary exercise in VE + HFD group led to significantly increased GPX and SOD activities, SIRT1 protein expression, sperm parameters, and decreased the expression of miR34a gene and Acp53 protein, and cellular apoptosis index compared to HFD group (p<0.001 to p<0.05). The SOD and catalase activities, SIRT1 protein expression, sperm parameters in VE + HFD group were lower than of those of VE group, however, MDA content, expression of Acp53 protein, apoptosis indexes in VE + HFD group was higher than that of VE group (p<0.001 to p<0.05).

CONCLUSION

This study revealed that voluntary exercise improved spermatogenesis, in part by decreasing the testicular oxidative stress status, apoptosis through alteration in miR-34a/SIRT1/p53 pathway.

Association Between Body Mass Index and Male Sperm Apoptosis and Apoptosis-Related Factors

BACKGROUND

Although obesity may affect reproductive functions, the molecular mechanisms of apoptosis-related biomarkers remain uncertain.

OBJECTIVE

To examine the effects of body mass index on sperm quality and apoptosis-related factors in seminal plasma of men.

METHODS

Data for 54 subfertile men were collected at our reproductive medical center. The men were divided into normal weight, overweight, and obese groups based on their body mass index (BMI). Sperm DNA fragmentation (sperm chromatin structure analysis), sperm apoptosis (annexin V), and sperm apoptosis-related factors (antibody array assay) were assessed and their relationships with BMI were analyzed.

RESULTS

BMI was not significantly related to age, duration of infertility, duration of sexual abstinence, semen volume, sperm concentration, or rate of normal sperm morphology (p > 0.05). However, progressive sperm motility was significantly reduced and the rates of sperm DNA fragmentation index (DFI) and sperm apoptosis were significantly increased in overweight and obese men compared with men with normal BMI. Fas/Fasl, Bcl-2/Bax, caspase-3, caspase-8, p53, and p21 were all upregulated in the overweight and obese groups. Protein function annotation by Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that apoptosis-related factors were enriched in a network associated with activation of apoptotic signaling pathways, such as apoptosis and p53 signaling.

CONCLUSION

These data suggest that increased BMI is associated with increased sperm apoptosis and sperm DNA damage, as well as accelerated expression of apoptosis-related factors via the activation of apoptotic signaling pathways.

Curcumin protects against palmitic acid-induced apoptosis via the inhibition of endoplasmic reticulum stress in testicular Leydig cells

BACKGROUND

Palmitic acid (PA) is a common saturated fatty acid that induces apoptosis in various types of cells, including testicular Leydig cells. There is evidence suggesting that PA is increased in patients with obesity and that PA-induced cell apoptosis may play an important role in obesity-related male infertility. Curcumin, a natural polyphenol, has been reported to exert cytoprotective effects in various cell types. However, the cytoprotective effect of curcumin against PA-induced apoptosis in Leydig cells remains unknown. Therefore, the current study was performed to investigate the protective effects of curcumin in response to PA-induced toxicity and apoptosis in murine Leydig tumor cell line 1 (MLTC-1) cells and explore the mechanism underlying its anti-apoptotic action.

METHODS

MLTC-1 cells were cultured in Roswell Park Institute-1640 medium and divided into five groups. First four groups were treated with 50-400 μM PA, 400 μM PA + 5-40 μM curcumin, 400 μM PA + 500 nM 4-phenylbutyric acid (4-PBA, an endoplasmic reticulum (ER) stress inhibitor), and 500 nM thapsigargin (TG, an ER stress inducer) + 20 μM curcumin, respectively, followed by incubation for 24 h. Effects of PA and/or curcumin on viability, apoptosis, and ER stress in MLTC-1 cells were then determined by cell proliferation assay, flow cytometry, and western blot analysis. The fifth group of MLTC-1 cells was exposed to 400 μM of PA and 5 IU/mL of human chorionic gonadotropin (hCG) for 24 h in the absence and presence of curcumin, followed by measurement of testosterone levels in cell-culture supernatants by enzyme-linked immunosorbent assay (ELISA). Rats fed a high-fat diet (HFD) were treated with or without curcumin for 4 weeks, and the testosterone levels were detected by ELISA.

RESULTS

Exposure to 100-400 μM PA reduced cell viability, activated caspase 3, and enhanced the expression levels of the apoptosis-related protein BCL-2-associated X protein (BAX) and ER stress markers glucose-regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP) in MLTC-1 cells. Treating cells with 500 nM 4-PBA significantly attenuated PA-induced cytotoxicity through inhibition of ER stress. Curcumin (20 μM) significantly suppressed PA- or TG-induced decrease in cell viability, caspase 3 activity, and the expression levels of BAX, CHOP, and GRP78. In addition, treating MLTC-1 cells with 20 μM curcumin effectively restored testosterone levels, which were reduced in response to PA exposure. Similarly, curcumin treatment ameliorated the HFD-induced decrease in serum testosterone level in vivo.

CONCLUSIONS

The present study suggests that PA induces apoptosis via ER stress and curcumin ameliorates PA-induced apoptosis by inhibiting ER stress in MLTC-1 cells. This study suggests the application of curcumin as a potential therapeutic agent for the treatment of obesity-related male infertility.

Sulforaphane ameliorates high-fat diet-induced spermatogenic deficiency in mice†

Sulforaphane (SFN), a dietary isothiocyanate that is mainly found in cruciferous vegetables, possesses anti-oxidative and anticancer activity and modulates inflammation. However, little is known about the role of SFN in obesity-related male reproductive defects. The present study aimed to investigate the effects of SFN on high-fat diet (HFD)-induced male spermatogenic impairment and further clarify the possible underlying mechanisms. In this study, 8-week-old mice were randomly divided into four groups. Mice were fed a normal diet or an HFD with or without SFN supplementation. Sulforaphane was subcutaneously injected at a dose of 0.5 mg/kg 5 days/week for 4 weeks beginning 8 weeks after initiation of the HFD. The results demonstrated that SFN could protect against HFD-induced reproductive dysfunction in male mice. Moreover, SFN also improved reproductive ability, as demonstrated by an increased pregnancy rate and decreased embryo resorption rate in comparison to the corresponding HFD group. We also observed a decrease in apoptosis and an attenuation of endoplasmic reticulum (ER) stress after SFN treatment. In vitro studies of mouse and human sperm samples also revealed that SFN protects against the palmitic acid-induced reduction in sperm viability and motility by inhibiting ER stress in an AMP-activated protein kinase (AMPK)-dependent manner. AMPK-dependent ER stress attenuation by SFN was further confirmed using AMPK knockout mice. Taken together, these data show that SFN protects against HFD-induced male reproductive dysfunction by inhibiting ER stress and apoptosis. These findings may be helpful for identifying new therapeutic methods to treat male infertility.

Metabolic treatment of syndrome linked with Parkinson's disease and hypothalamus pituitary gonadal hormones by turmeric curcumin in Bisphenol-A induced neuro-testicular dysfunction of wistar rat

The metabolic shift in cholinesterase activity and inhibitor of hypothalamus pituitary gonadal hormones were hypothesized as resultant effect of Parkinson's disease (PD) which is clinically characterized by a movement disorder. This study therefore examined the effect of turmeric curcumin (CUR) on index of PD, acetylcholine esterase activity and disorder of hypothalamus pituitary gonadal hormone (HPGH) in Bisphenol-A induced injury using animal model. Forty adult male albino rats were randomly distributed into five (n = 8) groups. Group I: vehicle control (olive oil 0.5 ml), Group II was given 50 mg/kg of BPA only, Group III was given 50 mg/kg BPA + 50 mg/kg curcumin, Group IV was given 50 mg/kg BPA + 100 mg/kg curcumin and Group V was administered 50 mg/kg of curcumin only for 14 days. The study examined the effect of curcumin on acetylcholineesterase (AChE) activity, nitric oxide radical (NO•) production, HPGH (LH, FSH and testosterone), MDA level, antioxidant enzymes (SOD and CAT), in BPA induced male rat. Sperm parameters were similarly examined. The animals induced with BPA exhibited impairment to striatum, leydig cells and sertoli cells by depleting LH, FSH, testosterone and spermatozoa with reduced AChE activity and significant (p < 0.05) alteration in cerebral enzymatic antioxidants. Locomotive activity was impeded followed by the increase of brain NO• level (marker of pro-inflammation). Therapeutically, CUR promoted hypothalamus-pituitary-testicular hormones via modulation of AChE and locomotive activities, reduction of intracellular NO• level, prevention of striatum-endocrine injury as well as oxidative damage. Hence, CUR abolished HPGH dysfunction linked with PD mediated by BPA in rat.

Grape seed proanthocyanidin extract alleviates high-fat diet induced testicular toxicity in rats

The present study aimed to investigate the protective effects of grape seed proanthocyanidin extract (GSPE) on high-fat diet (HFD) induced testicular damage, oxidative stress, and apoptotic germ cell death. Male rats (n = 40) were randomly divided into four groups: the control group (treated with physiological saline), HFD group, HFD + GSPE (100 mg kg⁻¹) group and HFD + GSPE (300 mg kg⁻¹) group. Compared with the HFD group the rats of the GSPE-treated group showed improved serum testosterone levels, sperm quality and histological appearance of the testis tissue. Significant elevation of antioxidant enzyme (SOD, GSH, and GSH-Px) activities and remarkable reduction in MDA were also observed by GSPE administration, indicating that GSPE can decrease testicular oxidative stress. Finally, a significant reduction in spermatogenic cell apoptosis was detected by TUNEL assay. In summary, these results indicated that GSPE can suppress testicular dysfunction and this effect may be attributed to its antioxidant and anti-apoptotic properties. The current study indicates that GSPE can be considered a promising candidate for use as a drug or a food supplement to alleviate HFD-induced testicular dysfunction.

GSPE alleviates high-fat diet induced testicular toxicity in rats by promoting anti-apoptotic activity.

Downregulation of leptin receptor and kisspeptin/GPR54 in the murine hypothalamus contributes to male hypogonadism caused by high-fat diet-induced obesity

PURPOSE

Obesity may lead to male hypogonadism, the underlying mechanism of which remains unclear. In the present study, we established a murine model of male hypogonadism caused by high-fat diet-induced obesity to verify the following hypotheses: 1) an increased leptin level may be related to decreased secretion of GnRH in obese males, and 2) repression of kisspeptin/GPR54 in the hypothalamus, which is associated with increased leptin levels, may account for the decreased secretion of GnRH and be involved in secondary hypogonadism (SH) in obese males.

METHODS

Male mice were fed high-fat diet for 19 weeks and divided by body weight gain into diet-induced obesity (DIO) and diet-induced obesity resistant (DIO-R) group. The effect of obesity on the reproductive organs in male mice was observed by measuring sperm count and spermatozoid motility, relative to testis and epididymis weight, testosterone levels, and pathologic changes. Leptin, testosterone, estrogen, and LH in serum were detected by ELISA method. Leptin receptor (Ob-R), Kiss1, GPR54, and GnRH mRNA were measured by real-time PCR in the hypothalamus. Expression of kisspeptin and Ob-R protein was determined by Western blotting. Expression of GnRH and GPR54 protein was determined by immunohistochemical analysis.

RESULTS

We found that diet-induced obesity decreased spermatozoid motility, testis and epididymis relative coefficients, and plasma testosterone and luteinizing hormone levels. An increased number and volume of lipid droplets in Leydig cells were observed in the DIO group compared to the control group. Significantly, higher serum leptin levels were found in the DIO and DIO-R groups. The DIO and DIO-R groups showed significant downregulation of the GnRH, Kiss1, GPR54, and Ob-R genes. We also found decreased levels of GnRH, kisspeptin, GPR54, and Ob-R protein in the DIO and DIO-R groups.

CONCLUSIONS

These lines of evidence suggest that downregulation of Ob-R and kisspeptin/GPR54 in the murine hypothalamus may contribute to male hypogonadism caused by high-fat diet-induced obesity.

In Utero and Postnatal Exposure to High Fat, High Sucrose Diet Suppressed Testis Apoptosis and Reduced Sperm Count

Obesity affects male fertility and maternal diabetes affects the offspring sperm epigenome. However, the effects of in utero exposure to maternal glucose intolerance in combination with postnatal high fat, high sucrose (HFHS) diet consumption on offspring spermatogenesis is not clear. The present study was designed to test these effects. One week before and during pregnancy, dams were fed either control or HFHS diet to induce gestational glucose intolerance, and returned to standard diet during lactation. Male offspring from each maternal group were split into control and HFHS-fed groups for eight weeks prior to sacrifice at 11, 19 or 31 weeks of age, and reproductive tissues were harvested for analysis of testicular germ cell apoptosis and sperm output. Postnatal HFHS diet suppressed spermatogonia apoptosis in all age groups and maternal HFHS diet reduced testosterone levels at 11 weeks. At 31 weeks of age, the postnatal HFHS diet increased body weight, and reduced epididymis weight and sperm count. The combination of in utero and postnatal exposure impacted sperm counts most significantly. In summary, HFHS diet during pregnancy puts male offspring at greater risk of infertility, particularly when combined with postnatal high fat diet feeding.

CTRP3 attenuates high-fat diet-induced male reproductive dysfunction in mice

Recent studies have suggested a role for abdominal obesity in male infertility. Previous studies have found that cell apoptosis exerts an important role in obesity-related male infertility. C1q/TNF-related protein 3 (CTRP3), a paralog of adiponectin, has been proposed to exert anti-apoptotic effects and to attenuate diabetes-related cardiac injuries. However, the role of CTRP3 in high-fat diet (HFD)-induced spermatogenic impairment remains unclear. In the present study, we fed male mice an HFD for 24 weeks to induce obesity. The expression of CTRP3 was decreased by HFD feeding. Supplementation with the recombinant human globular domain of CTRP3 (0.25 μg/g/day) for 4 weeks beginning at 20 weeks of the HFD improved spermatogenic function in the HFD-fed mice, which were characterized by improved testis morphology, increased testis weight/body weight ratio, and increased sperm count, sperm viability, and sperm motility. We also found that CTRP3 infusion resulted in the attenuation of endoplasmic reticulum (ER) stress and the activation of silence information regulator 1 (SIRT1) in the testes of obese mice. Our in vitro study also suggested that CTRP3 attenuated the palmitic acid (PA)-induced reductions in sperm viability and motility via the inhibition of ER stress. Moreover, germ cell-specific Sirtuin1 knockout abolished the protective effects of CTRP3 in vivo and in vitro. In vitro studies of human sperm showed that the protective effects of CTRP3 on sperm viability and motility were abrogated by a specific inhibitor of SIRT1. Thus, our results demonstrated that CTRP3 expression protected against HFD-induced spermatogenic deficiency through the SIRT1/ER stress pathway.

Effect of Antioxidants on Testicular iNOS and eNOS after High-Fat Diet in Rat

BACKGROUND AND OBJECTIVE

Spermatogenesis is a process by which germ cells produce spermatozoa and can be disturbed at every level. Nitric Oxide Synthases (NOS), implicate in interactions with Oxidative Stress (OS) which is one of the main factors in the etiology of male infertility. The High Fat Diet (HFD) is a major factor of obesity which in turn is important for enhancing OS. Antioxidants and garlic could attenuate or reverse effects of HFD. The aim of the study was to investigate the effects of dietary antioxidants and garlic on testicular inducible NOS (iNOS) and endothelial NOS (eNOS) in Wistar albino rats fed on HFD.

MATERIALS AND METHODS

Groups (each n = 8) were: SD (100% access to standard diet), F-HFD, (100% access to HFD) and R-HFD (70% access to HFD), F-HFD +antioxidants, F-HFD+garlic and R-HFD+antioxidants. The HFD consisted of a 60% fatty diet in 3 forms: Without antioxidants, with antioxidants and with garlic. The testicular iNOS and eNOS were studied by immunohistochemical (IHC) method. Also used ANOVA, repeated measures ANOVA, t-tests and Tukey's test (where necessary) to analyze the data (p<0.05).

RESULTS

The iNOS increased in the F-HFD and R-HFD+antioxidants groups. The eNOS increased in R-HFD,F-HFD and F-HFD+garlic groups. The H-E evaluation in R-HFD group showed a decrease in spermatogenesis score count and seminiferous tubules diameters (μm) in comparison with the SD and F-HFD groups. R-HFD+antioxidants group had lower score than F-HFD+antioxidants and F-HFD+garlic groups.

CONCLUSION

Restricted fat diet consumption causes increase in weight and impairs spermatogenesis. Results of this study reveal that adding the antioxidants can't improve histological changes of testis. The iNOS expression in seminiferous tubules in restricted fat diet along with antioxidants, suggest a potential role of iNOS in spermatogenesis and male infertility.

Diet-induced obesity impairs spermatogenesis: a potential role for autophagy

Autophagy is an evolutionarily conserved process that plays a crucial role in maintaining a series of cellular functions. It has been found that autophagy is closely involved in the physiological process of spermatogenesis and the regulation of sperm survival and motility. However, the role of autophagy in high-fat diet (HFD)-induced impaired spermatogenesis remains unknown. This study was designed to investigate the role of autophagy in HFD-induced spermatogenesis deficiency and employed chloroquine (CQ) to inhibit autophagy and rapamycin (RAP) to induce autophagy. 3-methyladenine (3-MA) and CQ were administered via intratesticular injection in vivo. The effects of CQ and 3-MA on the parameters of spermatozoa co-cultured with palmitic acid (PA) in vitro were also investigated. Human semen samples from obese, subfertile male patients were also collected to examine the level of autophagy. The results suggested that HFD mice subjected to CQ showed improved spermatogenesis. Inhibiting autophagy with CQ improved the decreased fertility of HFD male mice. Moreover, the in vivo and in vitro results indicated that both CQ and 3-MA could suppress the pathological changes in spermatozoa caused by HFD or PA treatment. Additionally, the excessive activation of autophagy was also observed in sperm samples from obese, subfertile male patients.