Baseline levels of seminal reactive oxygen species predict improvements in sperm function following antioxidant therapy in men with infertility

Omega-3 with and without insulin replacement alleviates detrimental effects of type II diabetes on reproductive system of male C57BL/6 mice

AIMS

this study aimed to examine the protective role of omega-3 and insulin on reproductive system of the male mouse model of type II diabetes mellitus (T2DM), especially DNA integrity and chromatin quality.

MAIN METHODS

adult age-matched mice were divided into intact, sham, or T2DM groups (n = 7) which received a high-fat diet/low-dose streptozotocin. T2DM-induced animals underwent no treatment as diabetic control (T2DM), received omega-3 (T2DM + Omg3), received insulin (T2DM + Ins) and their combination (T2DM + Omg3 + Ins) for 35 days. After which, testicular and sperm parameters and testosterone levels were evaluated.

KEY FINDINGS

our findings revealed that the various examined parameters were comparable between the intact and sham groups, while most testicular and sperm parameters were affected by T2DM. Treatment of T2DM-induced animals with omega-3, alone and in combination with insulin, significantly improved sperm motility, normal morphology, sperm chromatin quality, DNA integrity, Leydig cell number and non-significantly testosterone levels.

SIGNIFICANCE

T2DM interferes with spermatogenesis and steroidogenesis as well as sperm quality and DNA integrity, which can be partially ameliorated by long-term administration of omega-3 in combination with or without insulin. Although our findings should be confirmed in clinical studies, since previous clinical trials have found omega-3 consumption to be beneficial in humans, its use seems to be safe and effective.

The role of seminal reactive oxygen species assessment in the setting of infertility and early pregnancy loss

The male contribution to a couple suffering with adverse early pregnancy outcomes is being increasingly investigated. Seminal oxidative stress is considered to cause sperm DNA damage, thus affecting the functional capacity of the sperm. Multiple lines of evidence support an association between elevated seminal reactive oxygen species (ROS) and infertility. In the setting of assisted reproduction various factors in the in vitro environment, differing from the in vivo environment, may exacerbate oxidative stress. Furthermore, seminal ROS levels have been found to be higher in the male partners of couple's affected by both spontaneous and recurrent pregnancy loss. There are several methods by which to assess ROS levels however they are costly, inconsistent and their incorporation into clinical practice is unclear. The value of ROS assessment lies in the ability to plan targeted therapies to improve pregnancy and live birth rates. As such, further robust study is required before firm conclusions can be made to inform clinical practice. We aim to review the available evidence regarding the role of seminal ROS in infertility and pregnancy loss.

The Ameliorative Impact of Cichorium intybus L. Distillate on Reproductive Parameters in Male Mice

Background

Cichorium intybus L. (Kasni) distillate is widely used in Eastern countries as a safe herbal drink to improve male fertility. However, the potential effects on fertility parameters and possible adverse effects have not been studied experimentally. The current study aims to evaluate the impact of Cichorium intybus L. distillate (CD) on male mice fertility.

Methods

In the present study (Shiraz, Iran), 30 male mice (30-35 g) were divided into three groups. 10 mice received distilled water (DW) for five weeks as the control group. Another 10 mice, named group CD1/2, received chicory distillate of 1/2 dilution, and the other 10 mice received chicory distillate of CD1/4 dilution as CD1/4 group, ad libitum for three weeks, and they received DW for two weeks afterward. Experimental mice were sacrificed on day 35, and sperm analysis and sera collection were performed for further investigation of FSH, LH, testosterone, and some liver and kidney function parameters. We used the left testis for stereological analysis, and the right one was excised to investigate the expression of the androgen receptor gene. For statistical analysis using SPSS 18.0, mean±SD values were analyzed by one-way analysis of variance (ANOVA) with Dunnett's analysis as post hoc to compare between groups. In stereological investigations, the Kruskal-Wallis method was used for pairwise comparisons to compare groups. The P value was considered statistically significant at P<0.05.

Results

Treatment with CD1/2 resulted in the elevation of serum FSH (P=0.002), LH (P=0.009), testosterone (P=0.034), seminiferous tubule epithelium volume (P=0.029) and length (P=0.028), and Leydig cells number (P=0.009) in comparison with the control group. Administrating CD1/2 (P=0.038) and CD1/4 (P=0.013) significantly increased sperm count compared to the control group.

Conclusion

The results revealed that using chicory distillate can improve hormone levels and sperm count in male mice.

Oxidative versus reductive stress: a delicate balance for sperm integrity

Despite the long-standing notion of "oxidative stress," as the main mediator of many diseases including male infertility induced by increased reactive oxygen species (ROS), recent evidence suggests that ROS levels are also increased by "reductive stress," due to over-accumulation of reductants. Damaging mechanisms, like guanidine oxidation followed by DNA fragmentation, could be observed following reductive stress. Excessive accumulation of the reductants may arise from excess dietary supplementation over driving the one-carbon cycle and transsulfuration pathway, overproduction of NADPH through the pentose phosphate pathway (PPP), elevated levels of GSH leading to impaired mitochondrial oxidation, or as a result NADH accumulation. In addition, lower availability of oxidized reductants like NAD⁺, oxidized glutathione (GSSG), and oxidized thioredoxins (Trx-S2) induce electron leakage leading to the formation of hydrogen peroxide (H₂O₂). In addition, a lower level of NAD⁺ impairs poly (ADP-ribose) polymerase (PARP)-regulated DNA repair essential for proper chromatin integrity of sperm. Because of the limited studies regarding the possible involvement of reductive stress, antioxidant therapy remains a central approach in the treatment of male infertility. This review put forward the concept of reductive stress and highlights the potential role played by reductive vs oxidative stress at pre-and post-testicular levels and considering dietary supplementation.

Rhamnazin ameliorates 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin-evoked testicular toxicity by restoring biochemical, spermatogenic and histological profile in male albino rats

2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) is a potential environmental toxin that has the ability to affect male reproductive tract. Rhamnazin is a naturally present flavone that displays multiple medicinal properties. Therefore, the current study was designed to determine the mitigative role of rhamnazin against TCDD induced reproductive damage. 48 adult male albino rats were randomly separated into four groups: control, TCDD (10 µgkg-1), TCDD + rhamnazin (10 µgkg-1 + 5 mgkg-1 respectively) and rhamnazin (5 mgkg-1). The trial was conducted for 56 days. TCDD intoxication notably affected superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GSR) and catalase (CAT) activities, besides reactive oxygen species (ROS) and malondialdehyde (MDA) concentrations were augmented. TCDD administration also lowered sperm motility, viability, sperm number, while it augmented the sperm morphological (tail, neck/midpiece and head) anomalies. Moreover, it decreased the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and plasma testosterone. Moreover, TCDD reduced steroidogenic enzymes i.e., 17-beta hydroxysteroid dehydrogenase (17β-HSD), steroidogenic acute regulatory protein (StAR) and 3-beta hydroxysteroid dehydrogenase (3β-HSD) as well as B-cell lymphoma 2 (Bcl-2) expressions, but increased the expressions of Bcl-2-associated X protein (Bax) and cysteine-aspartic acid protease (Caspase-3). Furthermore, TCDD exposure also induced histopathological anomalies in testicular tissues. However, the supplementation of rhamnazin recovered all the mentioned damages in the testicles. The outcomes revealed that rhamnazin can ameliorate TCDD induced reproductive toxicity due to its anti-oxidant, anti-apoptotic and androgenic nature.

The Activated AMPK/mTORC2 Signaling Pathway Associated with Oxidative Stress in Seminal Plasma Contributes to Idiopathic Asthenozoospermia

Asthenozoospermia is a common form of abnormal sperm quality in idiopathic male infertility. While most sperm-mediated causes have been investigated in detail, the significance of seminal plasma has been neglected. Herein, we aimed to investigate the possible pathogenic factors leading to decreased sperm motility based on seminal plasma. Semen was collected from normo- (NOR, n = 70), idiopathic oligo- (OLI, n = 57), and idiopathic asthenozoospermic (AST, n = 53) patients. Using attenuated total reflection-Fourier transform infrared coupled with chemometrics, distinct differences in the biochemical compositions of nucleic acids, protein structure (amides I, II, and III), lipids, and carbohydrates in seminal plasma of AST were observed when compared to NOR and OLI. Compared with NOR and OLI, the levels of peptide aggregation, protein phosphorylation, unsaturated fatty acid, and lipid to protein ratio were significantly increased in AST; however, the level of lipid saturation was significantly decreased in seminal plasma of AST. Compared with NOR, the levels of ROS, MDA, 8-iso-prostaglandin F2α (8-isoPGF2α), and the ratio of phospho-AMPKα/AMPKα1 were significantly increased in AST; however, the levels of SOD, glutathione S-transferase (GSTs), protein carbonyl derivative (PC), and the ratio of phospho-Rictor/Rictor were significantly decreased in seminal plasma of AST. Changes of the AMPK/mTORC2 signaling in the seminal microenvironment possibly induce abnormal glucose and lipid metabolism, which impairs energy production. Oxidative stress potentially damages seminal plasma lipids and proteins, which in turn leads to impaired sperm structure and function. These findings provide evidence that the changes in seminal plasma compositions, oxidative stress, and activation of the AMPK/mTORC2 signaling contribute to the development of asthenozoospermia.

The Effect of Semen Cryopreservation Process on Metabolomic Profiles of Turkey Sperm as Assessed by NMR Analysis

Semen cryopreservation represents the main tool for preservation of biodiversity; however, in avian species, the freezing−thawing process results in a sharp reduction in sperm quality and consequently fertility. Thus, to gain a first insight into the molecular basis of the cryopreservation of turkey sperm, the NMR-assessed metabolite profiles of fresh and frozen−thawed samples were herein investigated and compared with sperm qualitative parameters. Cryopreservation decreased the sperm viability, mobility, and osmotic tolerance of frozen−thawed samples. This decrease in sperm quality was associated with the variation in the levels of some metabolites in both aqueous and lipid sperm extracts, as investigated by NMR analysis. Higher amounts of the amino acids Ala, Ile, Leu, Phe, Tyr, and Val were found in fresh than in frozen−thawed sperm; on the contrary, Gly content increased after cryopreservation. A positive correlation (p < 0.01) between the amino acid levels and all qualitative parameters was found, except in the case of Gly, the levels of which were negatively correlated (p < 0.01) with sperm quality. Other water-soluble compounds, namely formate, lactate, AMP, creatine, and carnitine, turned out to be present at higher concentrations in fresh sperm, whereas cryopreserved samples showed increased levels of citrate and acetyl-carnitine. Frozen−thawed sperm also showed decreases in cholesterol and polyunsaturated fatty acids, whereas saturated fatty acids were found to be higher in cryopreserved than in fresh sperm. Interestingly, lactate, carnitine (p < 0.01), AMP, creatine, cholesterol, and phosphatidylcholine (p < 0.05) levels were positively correlated with all sperm quality parameters, whereas citrate (p < 0.01), fumarate, acetyl-carnitine, and saturated fatty acids (p < 0.05) showed negative correlations. A detailed discussion aimed at explaining these correlations in the sperm cell context is provided, returning a clearer scenario of metabolic changes occurring in turkey sperm cryopreservation.

Effects of progesterone nanoparticles on the sperm capacitation and acrosome reaction in asthenozoospermia men

Low motility is one of the causes of male infertility. In this study, the effects of progesterone solid lipid nanoparticles (SLNs) on sperm capacitation, acrosome reaction, oxidative stress and expression of SPACA1 and MAPK way genes were investigated. Progesterone SLNs were synthesized using the solvent emulsification evaporation method. Twenty asthenozoospermia samples were selected, and sperm and acrosome membrane integrity, acrosome reaction, sperm motility, viability, total antioxidant capacity (TAC), total oxidative status tests and PKA, PTK, P38MAPK and SPACA1 gene expressions were assessed. The synthesized nanoparticles were prepared with the size (187.6 nm), PDI (0.184), EE (85.82%), LP (3.43%) and ZP (-23.5mV). Progesterone SLNs increased sperm and acrosome membrane integrity and TAC (p < .05). Also, the expression of P38MAPK, PKA, PTK, and SPACA1 genes in this group showed a significant increase (p < .001). Progesterone SLNs increased acrosome reaction, sperm capacitation and TAC. Also, it increased the expression of PTK PKA, SPACA1 and P38MAPK genes.

Assessment and Establishment of Correlation between Reactive Oxidation Species, Citric Acid, and Fructose Level in Infertile Male Individuals: A Machine-Learning Approach

Background:

Biochemical complexity of seminal plasma and obesity has an important role in male infertility (MI); so far, it has not been possible to provide evidence of clinical significance for all of them.

Aims:

Our goal here is to evaluate the correlation between biochemical markers with semen parameters, which might play a role in MI.

Study Setting and Design:

We enlisted 100 infertile men as patients and 50 fertile men as controls to evaluate the sperm parameters and biochemical markers in ascertaining MI.

Materials and Methods:

Semen analyses, seminal fructose, citric acid, and reactive oxidation species (ROS) were measured in 100 patients and 50 controls.

Statistical Analysis:

Descriptive statistics, an independent t-test, Pearson correlation, and machine-learning approaches were used to integrate the various biochemical and seminal parameters measured to quantify the inter-relatedness between these measurements.

Results:

Pearson correlation results showed a significant positive correlation between body mass index (BMI) and fructose levels. Citric acid had a positive correlation with sperm count, morphology, motility, and volume but displayed a negative correlation with BMI and basal metabolic rate (BMR). However, BMI and BMR had a positive correlation with ROS. Sperm count, morphology, and motility were negative correlations with ROS. The machine-learning approach detected that pH was the most critical parameter with an inverse effect on citric acid, and BMI and motility were the most critical parameter for ROS.

Conclusion:

We recommend that evaluation of biochemical markers of seminal fluid may benefit in understanding the etiology of MI based on the functionality of accessory glands and ROS levels.

Impact of the vegan diet on sperm quality and sperm oxidative stress values: A preliminary study

Background:

Insufficient nutrition and inappropriate diet have been related to many diseases. Although the literature confirms the hypothesis that particular nutritional factors can influence the quality of semen, until today, there are no specific dietary recommendations created for infertile males. Since the male contribution to the fertility of a couple is crucial, it is of high importance to determine the dietary factors that can affect male fertility.

Aim:

The aim of the present study was to evaluate differences in sperm quality parameters, sperm oxidative stress values and sperm acrosome reaction between vegan diet consumers and non-vegans.

Setting and Design:

Prospective study in a University Medical School.

Materials and Methods:

The present study was undertaken to evaluate the sperm quality parameters of vegan diet consumers (10 males who had a strictly vegetable diet with no animal products) and compare them with non-vegans (10 males with no diet restrictions). Semen quality was assessed following the World Health Organization (2010) criteria. Acrosome and DNA integrity has been evaluated using the immunofluorescence technique.

Statistical Analysis:

All variables were analysed by IBM SPSS version 24. Mean differences among groups were compared by Mann–Whitney U-test.

Results:

Obtained results showed that total sperm count (224.7 [117–369] vs. 119.7 [64.8–442.8]; P = 0.011) and the percentage of rapid progressively motile sperm were significantly higher in the vegan group compared with the non-vegan group (1 [0–7] vs. 17.5 [15–30]; P < 0.0001). Furthermore, the oxidation-reduction potential (0.4 [0.3–0.9] vs. 1.5 [0.6–2.8]; P < 0.0001) and the proportion of spermatozoon with DNA damage (14.7 [7–33.5] vs. 8.2 [3–19.5]; P = 0.05) were significantly higher in the non-vegan group in comparison to the vegan group.

Conclusions:

Results obtained in this study provide additional evidence about the favourable effect of a plant-based diet on sperm parameters. To confirm our preliminary findings, further studies including larger cohorts are warranted.