The Role of Seminal Oxidative Stress in Recurrent Pregnancy Loss

Enhancing Male Fertility: The Role of Crocin in Boosting Sperm Motility Through Antioxidant Activity and Mitochondrial Pathways

Excessive production of reactive oxygen species (ROS) is a critical factor adversely affecting semen quality, particularly sperm motility. Crocin, a key compound of Crocus Sativus (saffron), is recognized for its antioxidant properties. This study aimed to investigate the potential of crocin to improve in vitro sperm motility in case of asthenozoospermia. Sperm samples from 95 patients with asthenozoospermia were incubated for 3 h at 37°C with varying concentrations of crocin (0, 0.2, 0.5, 1, or 1.5 mM). Sperm motility was assessed using time-lapse video microscopy. Intracellular ROS levels were evaluated through the DCFH-DA assay while ROS-induced damage was quantified through lipid peroxidation and carbonylated proteins levels. Catalase, superoxide dismutase, and glutathione peroxidase were analyzed. Additionally, mitochondrial function was assessed via mitochondrial activity via MTT assay and potential via Rh123 assay. Our findings revealed a significant increase in sperm velocity by 93% (G1) and 91% (G2) and in the distance traveled by motile spermatozoa by 76.5% (G1) and 72.1% (G2) (p < 0.001). ROS levels decreased by 1.5-fold (G1) and 2.4-fold in (G2) (p < 0.001), while malondialdehyde levels dropped twofold (G1) and 3.4-fold (G2) (p < 0.001). Carbonylated protein content decreased by 2.8-fold (G1) and threefold (G2) (p < 0.001). Improvements also included succinate dehydrogenase activity (2.14-fold in G1, 1.85-fold in G2, p < 0.001) and mitochondrial membrane potential (1.7-fold in G1, 1.9-fold in G2, p < 0.001). These findings highlight crocin's potential to enhance sperm motility and reduce oxidative stress in asthenozoospermic samples.

Quercetin-mediated restoration of high-fat diet-induced male reproductive dysfunction through modifying spermatogenesis and unraveling 3β-HSD, 17β-HSD, and StAR pathways

PURPOSE

We explored the astounding potential of quercetin (QRT) to counteract the determinantal impacts of a high-fat diet (HFD) on testicular function in rat model. The goal was to understand how QRT, and its mechanisms of action can protect testicular health from HFD.

METHODS

Rats were divided into four groups receiving a control diet, QRT supplement (100 mg/kg), HFD, or HFD plus QRT for 8 weeks. Afterward, assessments were conducted, and reproductive organs were analyzed for hormone levels, gene expression, and subjected to biochemical, histopathological, and immunohistochemical analyses.

RESULTS

The HFD caused substantial declines in testicular weight, accessory sex glands and epididymis. The HFD also negatively impacted sperm characteristics including reduced motility, viability, and count, along with impaired morphology. Additionally, the HFD decreased testosterone levels in the testes and serum, impaired antioxidant enzymes like superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase, and reduced expression of key steroid metabolism enzymes 17β-hydroxysteroid dehydrogenase (17β-HSD), 3β-hydroxysteroid dehydrogenase (3β-HSD), and steroidogenic acute regulatory protein (StAR) involved in testosterone synthesis. These changes were paired with enhanced testicular lipid peroxidation, nitrite, and the inflammatory marker tumor necrosis factor-alpha (TNF-α), reflecting the damaging еffеcts of the HFD. Examination of testicular tissues verified structural damage and significantly fewer proliferating cell nuclear antigen (PCNA)-positive spermatogenic cells in seminiferous tubules of HFD-fed group, confirming HFD's adverse еffеcts.

CONCLUSION

QRT supplementation was able to curb the harmful impacts of the HFD on testicular spermatogenesis and steroidogenesis through its antioxidant, anti-inflammatory and androgen boosting properties.

Pharmacological and toxicological characteristics of baicalin in preventing spontaneous abortion and recurrent pregnancy loss: A multi-level critical review

Relevance

Spontaneous abortion (SAB) and recurrent pregnancy loss (RPL) occur alone or concurrently with increasing incidences recently. Scutellaria baicalensis Georgi (SBG) has been used to prevent pregnancy loss for thousands of years, which is recognized as a "pregnancy-stabilizing herb" in ancient China. Baicalin (BA) and its metabolite baicalein (BE) are the main bioactive flavonoids in the root of SBG.

Methods

In this study, we focused particularly on the metabolism, toxicology, and pharmacological effects of BA at the maternal-fetal interface based on the biological process prediction by network pharmacology. Focused on the systematic review of BA's regulatory mechanisms of immune homeostasis, cell proliferation and invasion, programmed cell death, inflammatory microenvironment, angiogenesis, oxidative stress and vascular remodeling at the maternal-fetal interface, it was found that BA exerts its biological effects to treat SAB and RPL through multiple perspectives and targets. We also critically elucidated the limitations of using BA from a clinical perspective.

Results

We explored the bioavailability, targeting and efficacy of BA from a new perspective (optimization of the BA delivery system, organoid studies based on BA, potential effects of BA on uterine flora and bioactive components). Finally, we propose a multimodal stereo sequencing study of biologically active components based on pathological dynamics incorporating single-cell RNA sequencing, spatially resolved transcriptomics, and single-cell multimodal omics to delve deeper into the fetal-preserving mechanism of BA and to promote the application of BA in clinical practice.

Yoga: As a Transformative Approach to Addressing Male Infertility and Enhancing Reproductive Health in Men: A Narrative Review

Infertility presents multifaceted challenges that encompass both physical and emotional burdens. Yoga, as a comprehensive system of mind-body medicine, serves as an effective intervention for managing male factor infertility, a complex lifestyle disorder with significant psychosomatic elements. This review explores the transformative role of yoga in addressing both the emotional and physical dimensions of infertility. By incorporating physical postures, breath control and meditation, yoga promotes emotional well-being and enhances reproductive health by improving the integrity of nuclear and mitochondrial genomes as well as the epigenome. In addition, yoga contributes to maintaining sperm telomere length through the regulation of seminal free radical levels and increased telomerase activity, which are crucial for optimal embryo cleavage and the development of high-quality blastocysts. Integrating yoga as an adjunctive therapeutic approach fosters a supportive intrauterine environment and facilitates physiological homoeostasis, thereby increasing the likelihood of successful fertilisation and implantation. Gentle asanas and flowing sequences promote relaxation, alleviate tension and cultivate emotional stability, while meditation aids in emotional healing and resilience during the infertility journey. Specific asanas, such as Baddha Konasana (bound angle pose), Bhujangasana (cobra pose) and Sarvangasana (shoulder stand), stimulate reproductive organs, enhance blood circulation and regulate hormone production. Pranayama techniques further support endocrine balance and overall vitality. Moreover, yoga provides a non-invasive strategy for managing fertility-related conditions leading to improved reproductive health and overall well-being. This review aims to elucidate the comprehensive role of yoga in improving male infertility, focusing on its impact on sperm nuclear and mitochondrial genomes, the epigenome and telomere health. In addition, it underscores the importance of self-care, open communication and shared experiences with partners. Practicing yoga regularly supports psychosocial well-being, promotes holistic healing, enhances physical and mental health and probably helps in improving reproductive health, thereby fostering resilience and self-efficacy throughout the journey of fertility and reproduction.

Exploring Differentially Expressed Sperm miRNAs in Idiopathic Recurrent Pregnancy Loss and Their Association with Early Embryonic Development

The high incidence of idiopathic recurrent pregnancy loss (iRPL) may stem from the limited research on male contributory factors. Many studies suggest that sperm DNA fragmentation and oxidative stress contribute to iRPL, but their roles are still debated. MicroRNAs (miRNAs) are short non-coding RNAs that regulate various biological processes by modulating gene expression. While differential expression of specific miRNAs has been observed in women suffering from recurrent miscarriages, paternal miRNAs remain unexplored. We hypothesize that analyzing sperm miRNAs can provide crucial insights into the pathophysiology of iRPL. Therefore, this study aims to identify dysregulated miRNAs in the spermatozoa of male partners of iRPL patients. Total mRNA was extracted from sperm samples of iRPL and control groups, followed by miRNA library preparation and high-output miRNA sequencing. Subsequently, raw sequence reads were processed for differential expression analysis, target prediction, and bioinformatics analysis. Twelve differentially expressed miRNAs were identified in the iRPL group, with eight miRNAs upregulated (hsa-miR-4454, hsa-miR-142-3p, hsa-miR-145-5p, hsa-miR-1290, hsa-miR-1246, hsa-miR-7977, hsa-miR-449c-5p, and hsa-miR-92b-3p) and four downregulated (hsa-miR-29c-3p, hsa-miR-30b-5p, hsa-miR-519a-2-5p, and hsa-miR-520b-5p). Functional enrichment analysis revealed that gene targets of the upregulated miRNAs are involved in various biological processes closely associated with sperm quality and embryonic development.

Seminal Oxidative Stress and Sperm DNA Fragmentation in Men from Couples with Infertility or Unexplained Recurrent Pregnancy Loss

(1) Background: This case-control study examined whether men from couples with unexplained recurrent pregnancy loss (RPL) or infertility exhibited higher seminal oxidative stress (OS) and sperm DNA fragmentation (SDF) compared to fertile controls. (2) Methods: The study included 30 participants from each group: unexplained RPL, unexplained infertility, and proven fertility. Data were collected at Aalborg University Hospital tertiary RPL and fertility treatment clinics (Aalborg, Denmark), excluding couples with mixed conditions for homogeneity. Semen samples were analyzed using computer-aided sperm analysis (CASA) for concentration, motility, and morphology. SDF was assessed via a CASA-based sperm chromatin dispersion test. OS was measured as static oxidation-reduction potential (sORP). (3) Results: The results showed no significant OS differences between groups. The RPL group had significantly lower SDF levels than the control group. A significant positive correlation between SDF and OS was observed in the infertility group. Overall, this study did not find significant differences in OS levels between men from couples with unexplained RPL or infertility and fertile controls, while SDF levels were lower in the RPL group compared to controls. (4) Conclusion: In conclusion, despite the existing literature suggesting that OS and SDF are negative prognostic factors, our findings suggest they may not be reliable diagnostic markers for RPL and infertility.

Recurrent miscarriage and male factor infertility: diagnostic and therapeutic implications. A narrative review

Introduction

Recurrent miscarriage is defined as 2 or more failed clinical pregnancies, typically known as repeated pregnancy loss, occurring before 20 gestational weeks, and further categorized into primary and secondary types. It represents a common and distressing condition to deal with in the field of reproductive medicine, usually affecting <5% of couples, with up to 50% of cases lacking a clearly defined aetiology. The epidemiology also varies depending on maternal age. Remarkably, the situation significantly afflicts expecting parents, whereas maternal factors, such as age and previous pregnancy loss rate, are commonly reported as risk factors. Although previously underestimated, existing evidence suggests the male factor is a possible cause of recurrent pregnancy loss.

Material and methods

A non-systematic literature review was conducted in the PubMed and Scopus databases for articles written in English investigating the possible association of the male factor in recurrent pregnancy loss. The eligible studies were synthesized in a narrative review format upon discussion and consensus among the authors after being previously independently assessed and selected.

Results

Lifestyle, obesity, genetic predisposition, chromosomal anomalies, endocrine dysfunction, anatomical abnormalities, immunological factors, infections, and oxidative stress can result in poor embryo development and recurrent miscarriage. Although professional organizations currently recognize male gender as a possible risk factor, specific recommendations on the diagnostic and therapeutic field are still lacking, and the condition necessitates a high level of suspicion and case-by-case management.

Conclusions

In this review, we delve deeper into the contribution of the male factor in the concept of recurrent miscarriage.

Antioxidant Effects of Myo-Inositol Improve the Function and Fertility of Cryopreserved Boar Semen

During cryopreservation, sperm undergoes structural and molecular changes such as ice crystal formation, DNA fragmentation, and reactive oxygen species (ROS) production, leading to decreased sperm quality after thawing. Antioxidants play a crucial role in preventing these damages, both in vivo and in vitro. One potent antioxidant is myo-inositol, known for its protective effects on sperm against ROS. This study aimed to investigate the protective effect of myo-inositol on cryopreserved boar semen. The semen was diluted, cooled, and cryopreserved using a BF5 extender. It was then divided into five groups: control and different concentrations of myo-inositol (0.5, 1, 1.5, and 2 mg/mL). The post-thaw evaluation included assessments of motility, viability, acrosome integrity, mitochondrial membrane potential (MMP), caspase activity, gene expression, ROS levels, apoptosis, and IVF with treated semen. Results showed that myo-inositol at 0.5 mg/mL improved motility, acrosome integrity, and fertilization ability. It also reduced the expression of pro-apoptotic genes and increased SMCP expression. Lower concentrations also demonstrated improved viability and reduced apoptosis and ROS levels. In conclusion, myo-inositol treatment during cryopreservation improved sperm quality, reduced apoptosis and ROS levels, and enhanced fertility rates in boar semen.