Genetically induced oxidative stress in mice causes thrombocytosis, splenomegaly and placental angiodysplasia that leads to recurrent abortion

Identification and analysis of biomarkers associated with oxidative stress and ferroptosis in recurrent miscarriage

Recurrent miscarriage (RM) has a huge impact on women. Both oxidative stress and ferroptosis play an important role in the pathogenesis of RM. Hence, it was vital to screen the ferroptosis oxidation-related biomarkers for the diagnosis and treatment of RM. We introduced transcript data to screen out differentially expressed genes (DEGs) in RM. Ferroptosis oxidation-related differentially expressed genes were obtained by overlapping DEGs and oxidative stress related genes with correlations >0.9 with ferroptosis-related genes. Least Absolute Shrinkage and Selectionator operator regression and support vector machine based recursive feature elimination algorithm were implemented to screen feature genes. The biomarkers associated with ferroptosis oxidation were screened via receiver operating characteristic curve analysis. We finally analyzed the competing endogenous RNAs regulatory network and potential drugs of biomarkers. We identified 1047 DEGs in RM. Then, 9 ferroptosis oxidation-related differentially expressed genes were obtained via venn diagram. Subsequently, 8 feature genes (PTPN6, GJA1, HMOX1, CPT1A, CREB3L1, SNCA, EPAS1, and TGM2) were identified via machine learning. Moreover, 4 biomarkers associated with ferroptosis oxidation, including PTPN6, GJA1, CPT1A, and CREB3L1, were screened via receiver operating characteristic curve analysis. We constructed the '227 long noncoding RNAs-4 mRNAs-36 microRNAs' network, in which hsa-miR-635 was associated with CREB3L1 and PTPN6. There were 11 drugs with therapeutic potential on 3 biomarkers associated with ferroptosis oxidation. We also observed higher expression of CPT1A and CREB3L1 in RM group compared to the healthy control group by quantitative real-time reverse transcription polymerase chain reaction. Overall, we obtained 4 biomarkers (PTPN6, GJA1, CPT1A, and CREB3L1) associated with ferroptosis and oxidative stress, which laid a theoretical foundation for the diagnosis and treatment of RM.

A preliminary study unveils CISD2 as a ferroptosis-related therapeutic target for recurrent spontaneous abortion through immunological analysis and two-sample mendelian randomization

Recurrent spontaneous abortion (RSA) affects approximately 1 % of women striving for conception, posing a significant clinical challenge. This study aimed to identify a prognostic signature in RSA and elucidate its molecular mechanisms. Prognostic gene impacts were further assessed in HTR-8/SVneo and human primary extravillous trophoblast (EVT) cells in vitro experiments. A total of 6168 differentially expressed genes (DEGs) were identified, including 3035 upregulated and 3133 downregulated genes. WGCNA pinpointed 8 significant modules and 31 ferroptosis-related DEGs in RSA. Optimal clustering classified RSA patients into three distinct subgroups, showing notable differences in immune cell composition. Six feature genes (AEBP2, CISD2, PML, RGS4, SRSF9, STK11) were identified. The diagnostic model showed high predictive capabilities (AUC: 0.966). Mendelian randomization indicated a significant association between CISD2 levels and RSA (OR: 1.069, P-value: 0.049). Furthermore, the downregulation of CISD2 promotes ferroptosis in HTR-8/SVneo and human primary EVT cells. CISD2 emerged as a pivotal gene in RSA, serving as a ferroptosis-related therapeutic target. The diagnostic model based on gene expression and Mendelian randomization provides novel insights into the pathogenesis of RSA.

Supplementing Ryegrass Ameliorates Commercial Diet-Induced Gut Microbial Dysbiosis-Associated Spleen Dysfunctions by Gut-Microbiota-Spleen Axis

The type and composition of food strongly affect the variation and enrichment of the gut microbiota. The gut-microbiota-spleen axis has been developed, incorporating the spleen's function and maturation. However, how short-chain fatty-acid-producing gut microbiota can be considered to recover spleen function, particularly in spleens damaged by changed gut microbiota, is unknown in geese. Therefore, the gut microbial composition of the caecal chyme of geese was assessed by 16S rRNA microbial genes, and a Tax4Fun analysis identified the enrichment of KEGG orthologues involved in lipopolysaccharide production. The concentrations of LPS, reactive oxygen species, antioxidant/oxidant enzymes, and immunoglobulins were measured from serum samples and spleen tissues using ELISA kits. Quantitative reverse transcription PCR was employed to detect the Kelch-like-ECH-associated protein 1-Nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2), B cell and T cell targeting markers, and anti-inflammatory/inflammatory cytokines from the spleen tissues of geese. The SCFAs were determined from the caecal chyme of geese by using gas chromatography. In this study, ryegrass-enriched gut microbiota such as Eggerthellaceae, Oscillospiraceae, Rikenellaceae, and Lachnospiraceae attenuated commercial diet-induced gut microbial alterations and spleen dysfunctions in geese. Ryegrass significantly improved the SCFAs (acetic, butyric, propionic, isovaleric, and valeric acids), AMPK pathway-activated Nrf2 redox signaling cascades, B cells (B220, CD19, and IgD), and T cells (CD3, CD4, CD8, and IL-2, with an exception of IL-17 and TGF-β) to activate anti-inflammatory cytokines (IL-4 and IL-10) and immunoglobulins (IgA, IgG, and IgM) in geese. In conclusion, ryegrass-improved reprogramming of the gut microbiota restored the spleen functions by attenuating LPS-induced oxidative stress and systemic inflammation through the gut-microbiota-spleen axis in geese.

Melatonin-mediated actions and circadian functions that improve implantation, fetal health and pregnancy outcome

This review summarizes data related to the potential importance of the ubiquitously functioning antioxidant, melatonin, in resisting oxidative stress and protecting against common pathophysiological disorders that accompany implantation, gestation and fetal development. Melatonin from the maternal pineal gland, but also trophoblasts in the placenta, perhaps in the mitochondria, produce this molecule as a hedge against impairment of the uteroplacental unit. We also discuss the role of circadian disruption on reproductive disorders of pregnancy. The common disorders of pregnancy, i.e., stillborn fetus, recurrent fetal loss, preeclampsia, fetal growth retardation, premature delivery, and fetal teratology are all conditions in which elevated oxidative stress plays a role and experimental supplementation with melatonin has been shown to reduce the frequency or severity of these conditions. Moreover, circadian disruption often occurs during pregnancy and has a negative impact on fetal health; conversely, melatonin has circadian rhythm synchronizing actions to overcome the consequences of chronodisruption which often appear postnatally. In view of the extensive findings supporting the ability of melatonin, an endogenously-produced and non-toxic molecule, to protect against experimental placental, fetal, and maternal pathologies, it should be given serious consideration as a supplement to forestall the disorders of pregnancy. Until recently, the collective idea was that melatonin supplements should be avoided during pregnancy. The data summarized herein suggests otherwise. The current findings coupled with the evidence, published elsewhere, showing that melatonin is highly protective of the fertilized oocyte from oxidative damage argues in favor of its use for improving pregnancy outcome generally.

Disturbed Follicular Microenvironment in Polycystic Ovary Syndrome: Relationship to Oocyte Quality and Infertility

Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with infertility and poor reproductive outcomes. The follicular fluid (FF) microenvironment plays a crucial role in oocyte development. This review summarizes evidence elucidating the alterations in FF composition in PCOS. Various studies demonstrated a pronounced proinflammatory milieu in PCOS FF, characterized by increased levels of cytokines, including but not limited to interleukin-6 (IL-6), tumor necrosis factor α, C-reactive protein, and IL-1β, concomitant with a reduction in anti-inflammatory IL-10. T lymphocytes and antigen-presenting cells are dysregulated in PCOS FF. PCOS FF exhibit heightened reactive oxygen species production and the accumulation of lipid peroxidation byproducts, and impaired antioxidant defenses. Multiple microRNAs are dysregulated in PCOS FF, disrupting signaling critical to granulosa cell function. Proteomic analysis reveals changes in pathways related to immune responses, metabolic perturbations, angiogenesis, and hormone regulation. Metabolomics identify disturbances in glucose metabolism, amino acids, lipid profiles, and steroid levels with PCOS FF. Collectively, these pathological alterations may adversely affect oocyte quality, embryo development, and fertility outcomes. Further research on larger cohorts is needed to validate these findings and to forge the development of prognostic biomarkers of oocyte developmental competence within FF. Characterizing the follicular environment in PCOS is key to elucidating the mechanisms underlying subfertility in this challenging disorder.

Heat Stress-Induced Fetal Intrauterine Growth Restriction Is Associated with Elevated LPS Levels Along the Maternal Intestine-Placenta-Fetus Axis in Pregnant Mice

The exacerbation of the greenhouse effect has made heat stress (HS) an important risk factor for the occurrence of intrauterine growth restriction (IUGR). The experiment aims to uncover the effects of maternal HS on IUGR and its mechanisms. The results showed that HS leads to decreased maternal and fetal birth weights, accompanied by increased serum oxidative stress and cortisol levels. Moreover, HS inflicted significant damage to both the intestinal and placental barriers, altering maternal gut microbiota and increasing intestinal LPS levels. As a result, LPS levels increased in maternal serum, placenta, and fetus. Furthermore, HS damaged the intestinal structure, intensifying inflammation and disrupting the redox balance. The placenta exposed to HS exhibited changes in the placental structure along with disrupted angiogenesis and decreased levels of nutritional transporters. Additionally, the leakage of LPS triggered placental JNK and ERK phosphorylation, ultimately inducing severe placental inflammation and oxidative stress. This study suggests that LPS translocation from the maternal intestine to the fetus, due to a disrupted gut microbiota balance and compromised intestinal and placental barrier integrity, may be the primary cause of HS-induced IUGR. Furthermore, increased LPS leakage leads to placental inflammation, redox imbalance, and impaired nutrient transport, further restricting fetal growth.

Oxidative stress-induced by different stressors alters kidney tissue antioxidant markers and levels of creatinine and urea: the fate of renal membrane integrity

The cellular integrity of the kidney in homeostatic regulation has constantly been compromised by oxidative stress following exposure to varying nature of stressor present within the environment. The objective of the work was to evaluate the renal effect of the different stressor stimuli applied. Twenty-four adult female rats weighing averagely 160-200 g and within the ages of 12-14 weeks were used for experiment-1, while 12 offspring were utilized for experiment-2. Three stress models namely; restraint, mirror chamber and cat intruder stressors were used. Tissues were isolated from the animal and homogenized for tissue antioxidant assay. Serum was collected for assays of urea and creatinine for the kidney function test using ELISA. Data collected were analyzed for Mean ± SEM using One Way ANOVA. The present study revealed that exposure of rats to different stressors reduced relative kidney weights but did not significantly alter serum creatinine concentration in the Wistar rats, although the concentrations were slightly increased compared to controls. Urea concentration was significantly (p < 0.05) increased in rats exposed to restraint and intruder stressors. Exposure to a mirror chamber stressor did not significantly alter urea concentration. Offspring from parents of stressed female rats exhibited a significant (p < 0.05) increase in serum urea level, minimal increase in serum creatinine levels. GSH and GST levels showed no significant difference when compared to control group, whereas, GPx were significantly (p < 0.05) decreased irrespective of the stressor applied. SOD activity were significantly (p < 0.05) reduced in the group exposed to restraint or cat intruder stressor. CAT activities were significantly (p < 0.05) reduced in the rats exposed to restraint or cat intruder stressor. In all, the different stress model altered the antioxidant capacity of the kidney tissues. Exposure of rats to a stressful condition of the different nature of stressor has the tendency of compromising the functional integrity of the kidney, thus, with the potency of complicating female renal function.

Placental Angiodysplasia: A New Sign for Prediction of Fetal Outcome?

The study of the placenta is of great importance, not only in the attempt to understand the etiopathogenesis of various maternal-fetal pathologies, but also in the attempt to understand whether it is possible to find the cause of pathological neonatal outcomes. On the other hand, abnormalities of blood vessel formation, such as angiodysplasias, have been poorly characterised in the literature, and there is a need for more studies investigating the potential impact on the fetus. In this paper, we retrospectively analysed 2063 placentas received at the Department of Pathology of the University of Bari 'Aldo Moro', among which we identified 70 placentas affected by angiodysplasia. On these placentas, we carried out histochemical staining with Masson's Trichrome, orcein-alcian blue, and, subsequently, immunostaining with anti-CD31, CD34, and desmin and actin muscle smoothness antibodies. Finally, we performed a morphometric analysis on the allantochorionic and truncal vessels and correlated the results with neonatal outcomes. We studied the characteristics of the angiodysplasias in detail, dividing the patients into two classes (A and B) according to the morphology and histochemical characteristics of the affected vessels; statistical analysis reported a statistically significant association (p < 0.05) between the ratio of maximum thickness to maximum diameter (Tmax/Dmax) and neonatal outcome, with only 30% physiological outcome in the cohort of the placentas affected by angiodysplasia. These results shed light on a rather neglected aspect in the 2015 Amsterdam Classification, as well as in the literature, and provided strong evidence that placental angiodysplasia is predictive of an increased likelihood of the pathological fetal outcome, while other factors remain in the field. Studies with larger case series and guidelines with more attention to these aspects are mandated to further investigate the predictive potential of this pathology.

Association of Vascular Endothelial Growth Factors (VEGFs) with Recurrent Miscarriage: A Systematic Review of the Literature

Recurrent miscarriage (RM) can be defined as two or more consecutive miscarriages before 20 weeks' gestation. Vascular endothelial growth factors (VEGFs) play an important role in endometrial angiogenesis and decidualization, prerequisites for successful pregnancy outcomes. We conducted a systematic review of the published literature investigating the role of VEGFs in RM. In particular, we explored the methodological inconsistencies between the published reports on this topic. To our knowledge, this is the first systematic literature review to examine the role of VEGFs in RM. Our systematic search followed PRISMA guidelines. Three databases, Medline (Ovid), PubMed, and Embase, were searched. Assessment-bias analyses were conducted using the Joanna Bigger Institute critical appraisal method for case-control studies. Thirteen papers were included in the final analyses. These studies included 677 cases with RM and 724 controls. Endometrial levels of VEGFs were consistently lower in RM cases compared to controls. There were no consistent significant findings with respect to VEGFs levels in decidua, fetoplacental tissues, and serum when RM cases were compared to controls. The interpretation of studies that explored the relationship between VEGFs and RM is hampered by inconsistencies in defining clinical, sampling, and analytical variables. To clarify the association between VEGF and RM in future studies, researchers ideally should use similarly defined clinical groups, similar samples collected in the same way, and laboratory analyses undertaken using the same methods.

The interplay between hypovitaminosis D and the immune dysfunction in the arteriovenous thrombotic complications of the sever coronavirus disease 2019 (COVID-19) infection

Thromboembolic complications including cerebrovascular accidents, pulmonary embolism, myocardial infarction, deep vein thrombosis and disseminating intravascular coagulopathy are serious encounters in sever coronavirus disease 2019 (COVID-19) infected patients. This worsens the prognosis and may lead to death or life long morbidities. The laboratory finding of the disturbed haemostasias and the hyperinflammatory response are almost invariably present in COVID-19 patients. Multiple treatment modalities are utilized by the healthcare professionals to overcome the cytokine storm, oxidative stress, endothelial dysfunction, and coagulopathy in these patients. The combined actions of vitamin D (VitD) as a steroid hormone with anti-inflammatory, immunomodulatory, and antithrombotic properties increase the potential of the possible involvement of hypovitaminosis D in the thromboembolic complications of COVID-19 infection, and stimulated researchers and physicians to administer VitD therapy to prevent the infection and/or overcome the disease complications. The current review highlighted the immunomodulatory, anti-inflammatory, antioxidative and hemostatic functions of VitD and its interrelation with the renin-angiotensin-aldosterone system (RAAS) pathway and the complement system. Additionally, the association of VitD deficiency with the incidence and progression of COVID-19 infection and the associated cytokine storm, oxidative stress, hypercoagulability, and endothelial dysfunction were emphasized. Normalizing VitD levels by daily low dose therapy in patients with hypovitaminosis D below (25 nmol/l) is essential for a balanced immune response and maintaining the health of the pulmonary epithelium. It protects against upper respiratory tract infections and decreases the complications of COVID-19 infections. Understanding the role of VitD and its associated molecules in the protection against the coagulopathy, vasculopathy, inflammation, oxidative stress and endothelial dysfunction in COVID-19 infection could lead to new therapeutic strategies to prevent, treat, and limit the complications of this deadly virus infection.

Improvement of oocyte quality through the SIRT signaling pathway

Background

Oocyte quality is one of the major deciding factors in female fertility competence.

Methods

PubMed database was searched for reviews by using the following keyword "oocyte quality" AND "Sirtuins". The methodological quality of each literature review was assessed using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement.

Main Findings

Oxidative stress has been recognized as the mechanism attenuating oocyte quality. Increasing evidence from animal experiments and clinical studies has confirmed the protective roles of the sirtuin family in improving oocyte quality via an antioxidant effect.

Conclusion

The protective roles in the oocyte quality of the sirtuin family have been increasingly recognized.

Mitochondrial Electron Transport Chain Complex II Dysfunction Causes Premature Aging of Hematopoietic Stem Cells

Mitochondria are indispensable in maintaining hematopoietic stem cells (HSCs), and mitochondrial complex II (MCII) has been recognized as a key component of HSCs. However, the physiological role of MCII on long-term hematopoiesis and hematopoietic reconstitution capacity remains unknown. Hence, this study evaluated the impact of MCII dysfunctions on long-term HSC maintenance and hematopoietic homeostasis among conditional transgenic mice with a missense mutation in the succinate dehydrogenase complex subunit C gene (SdhcV69E). HSCs collected from SdhcV69E mice had a higher reactive oxygen species (ROS) accumulation and DNA damage in response to mitochondrial activation. Via the aging stress response, MCII dysfunctions caused decreased white blood cell count with myeloid-skewing property, macrocytic anemia, and thrombocytosis. Moreover, the HSCs of aged SdhcV69E mice exhibited greater ROS accumulation and lower membrane potential. Transplantation-induced replicative stress also caused premature senescent hematopoiesis. Furthermore, accelerated ROS accumulation and profound DNA damage in HSCs were observed in the SdhcV69E-derived cell recipients. The long-term hematopoietic reconstitution capacity was remarkably impaired in HSCs from the SdhcV69E-derived cell recipients. Taken together, MCII plays an essential role in long-term hematopoiesis, and MCII dysfunctions with aging or replicative stresses caused excessive ROS accumulation and DNA damage in HSCs, leading to premature senescence.

Succinate dehydrogenase complex subunit C: Role in cellular physiology and disease

Succinate dehydrogenase complex subunit C (SDHC) is a subunit of mitochondrial complex II (MCII), which is also known as succinate dehydrogenase (SDH) or succinate: ubiquinone oxidoreductase. Mitochondrial complex II is the smallest respiratory complex in the respiratory chain and contains four subunits. SDHC is a membrane-anchored subunit of SDH, which connects the tricarboxylic acid cycle and the electron transport chain. SDH regulates several physiological processes within cells, plays an important role in generating energy to maintain normal cell growth, and is involved in apoptosis. Currently, SDHC is generally recognized as a tumor-suppressor gene. SDHC mutations can cause oxidative damage in the body. It is closely related to the occurrence and development of cancer, neurodegenerative diseases, and aging-related diseases. Here, we review studies on the structure, biological function, related diseases of SDHC, and the mev-1 Animal Model of SDHC Mutation and its potential use as a therapeutic target of certain human diseases.

New insights into mechanisms of berberine in alleviating reproductive disorders of polycystic ovary syndrome: Anti-inflammatory properties

Polycystic ovary syndrome (PCOS) is a complex reproductive disorder that seriously harms female reproductive health and decreases quality of life. Although spontaneous or assisted ovulation occurs, women with PCOS suffer from poor-quality oocytes and embryos and lower fertilization and final pregnancy rates. Therefore, it is urgent to identify new pathological mechanisms and discover the underlying therapeutic targets for reproductive disorders associated with PCOS. Berberine, one of the famous traditional Chinese medicines, has been shown to improve ovulation and live birth rates in women with PCOS. The effects of berberine on insulin resistance and abnormal glucose and lipid metabolism for restoring the reproductive health of women with PCOS are well recognized and have been widely studied, but much less attention has been given to its anti-inflammatory properties. Chronic low-grade inflammation is the unifying feature of PCOS and may contribute to reproductive disorders in PCOS. Berberine can modulate the inflammatory state of the ovaries and uterus in PCOS. The anti-inflammatory properties of berberine may provide new insight into the mechanisms by which berberine alleviates reproductive disorders associated with PCOS. Here, we summarized the most recent insights into the anti-inflammatory properties of berberine in PCOS reproductive disorders to inspire researchers to pursue new study directions involving berberine.

Ambient fine particulate matter exposures and oxidative protein damage in early pregnant women

The association between oxidative protein damage in early pregnant women and ambient fine particulate matter (PM_2.5) is unknown. We estimated the effect of PM_2.5 exposures within seven days before blood collection on serum 3-nitrotyrosine (3-NT) and advanced oxidation protein products (AOPP) in 100 women with normal early pregnancy (NEP) and 100 women with clinically recognized early pregnancy loss (CREPL). Temporally-adjusted land use regression model was applied for estimation of maternal daily PM_2.5 exposure. Daily nitrogen dioxide (NO₂) exposure of each participant was estimated using city-level concentrations of NO₂. Single-day lag effect of PM_2.5 was analyzed using multivariable linear regression model. Net cumulative effect and distributed lag effect of PM_2.5 and NO₂ within seven days were analyzed using distributed lag non-linear model. In all 200 subjects, the serum 3-NT were significantly increased with the single-day lag effects (4.72%-8.04% increased at lag 0-2), distributed lag effects (2.32%-3.49% increased at lag 0-2), and cumulative effect within seven days (16.91% increased). The single-day lag effects (7.41%-10.48% increased at lag 0-1), distributed lag effects (3.42%-5.52% increased at lag 0-2), and cumulative effect within seven days (24.51% increased) of PM_2.5 significantly increased serum 3-NT in CREPL group but not in NEP group. The distributed lag effects (2.62%-4.54% increased at lag 0-2) and cumulative effect within seven days (20.25% increased) of PM_2.5 significantly increased serum AOPP in early pregnant women before the coronavirus disease (COVID-19) pandemic but not after that, similarly to the effects of NO₂ exposures. In conclusion, PM_2.5 exposures were associated with oxidative stress to protein in pregnant women in the first trimester, especially in CREPL women. Analysis of NO₂ exposures suggested that combustion PM_2.5 was the crucial PM_2.5 component. Wearing masks may be potentially preventive in PM_2.5 exposure and its related oxidative protein damage.

Oxidative stress on vessels at the maternal-fetal interface for female reproductive system disorders: Update

Considerable evidence shows that oxidative stress exists in the pathophysiological process of female reproductive system diseases. At present, there have been many studies on oxidative stress of placenta during pregnancy, especially for preeclampsia. However, studies that directly focus on the effects of oxidative stress on blood vessels at the maternal-fetal interface and their associated possible outcomes are still incomplete and ambiguous. To provide an option for early clinical prediction and therapeutic application of oxidative stress in female reproductive system diseases, this paper briefly describes the composition of the maternal-fetal interface and the molecular mediators produced by oxidative stress, focuses on the sources of oxidative stress and the signaling pathways of oxidative stress at the maternal-fetal interface, expounds the adverse consequences of oxidative stress on blood vessels, and deeply discusses the relationship between oxidative stress and some pregnancy complications and other female reproductive system diseases.

Association of male factors with recurrent pregnancy loss

The role of male factors in recurrent pregnancy loss (RPL) is receiving increased attention since sperm quantity and quality, male genetic mutations, as well as epigenetic modifications, have all been associated with RPL. A growing number of studies have been published on the relationship between male factors and RPL; however, these reports are limited due to small sample sizes, inconsistent inclusion criteria, and detection methods. Herein, we investigate the effects of several male factors on RPL from a genetic and non-genetic perspective to aid clinicians in determining the etiology and optimal treatment strategy for patients with RPL.

Morroniside Protects Human Granulosa Cells against H2O2-Induced Oxidative Damage by Regulating the Nrf2 and MAPK Signaling Pathways

Morroniside is the main ingredient of Cornus officinalis and has a variety of biological activities including antioxidative effects. Ovarian granulosa cells (GCs) are responsible for regulating the development and atresia of follicles, which are susceptible to oxidative stress. In this study, we determined whether morroniside can inhibit the oxidative stress of GCs induced by hydrogen peroxide (H₂O₂), leading to improved oocyte quality. The oxidative damage and apoptosis of ovarian GCs cultured in vitro were induced by the addition of H₂O₂. After pretreatment with morroniside, the levels of ROS, MDA, and 8-OHdG in ovarian GCs were significantly decreased. Morroniside significantly upregulated p-Nrf2 and promoted the nuclear translocation of Nrf2, which transcriptionally activated antioxidant SOD and NQO1. In addition, morroniside significantly regulated the levels of apoptosis-related proteins Bax, Bcl-2, cleaved caspase-9, and cleaved caspase-3 via the p38 and JNK pathways. These results suggest that morroniside can reduce the oxidative damage and apoptosis of ovarian GCs induced by H₂O₂.

Pathological Role of Reactive Oxygen Species on Female Reproduction

Oxidative stress (OS), a clinical predicament characterized by a shift in homeostatic imbalance among prooxidant molecules embracing reactive oxygen species (ROS) and reactive nitrogen species (RNS), along with antioxidant defenses, has been established to play an indispensable part in the pathophysiology of subfertility in both human males and females. ROS are highly reactive oxidizing by-products generated during critical oxygen-consuming processes or aerobic metabolism. A healthy body system has its own course of action to maintain the equilibrium between prooxidants and antioxidants with an efficient defense system to fight against ROS. But when ROS production crosses its threshold, the disturbance in homeostatic balance results in OS. Besides their noxious effects, literature studies have depicted that controlled and adequate ROS concentrations exert physiologic functions, especially that gynecologic OS is an important mediator of conception in females. Yet the impact of ROS on oocytes and reproductive functions still needs a strong attestation for further analysis because the disruption in prooxidant and antioxidant balance leads to abrupt ROS generation initiating multiple reproductive diseases such as polycystic ovary syndrome (PCOS), endometriosis, and unexplained infertility in addition to other impediments in pregnancy such as recurrent pregnancy loss, spontaneous abortion, and preeclampsia. The current article elucidates the skeptical state of affairs created by ROS that influences female fertility.

Suggested role of silent information regulator 1 (SIRT1) gene in female infertility: A cross-sectional study in Pakistan

AIM & OBJECTIVE

Silent information regulator 1 (SIRT1) gene stimulates the expression of antioxidants and repairs damaged cells. It affects the mitochondrial activity within the oocytes to overcome the oxidant stress. We aimed to assess an association of SIRT1 polymorphism (Tag SNPs rs10509291 and rs12778366) with fertility, and assess serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), oestradiol, progesterone, manganese superoxide (MnSOD) and SIRT1.

MATERIAL AND METHODS

In this cross-sectional study, 207 fertile and 135 infertile subjects between the ages of 18-45 years were recruited. Polymerase chain reaction (PCR) was performed; products were electrophoresed in a 2% agarose gel. Descriptive analysis of continuous variables was expressed as mean ± standard deviation. Mann-Whitney test was performed for comparison of groups, P value <.001 was considered significant. Single Nucleotide Polymorphism (SNP) data were analysed by applying chi-squared statistics.

RESULTS

All subjects were age matched (P = .896). SIRT1 levels were significantly lower in infertile females when compared with fertile subjects (P < .001). AA (rs10509291) and CC (rs12778366) variant frequency was higher in the infertile than fertile subjects (P < .01). Similarly, the frequency of A allele (rs10509291) and C allele (rs12778366) was higher in infertile subjects (P < .001). Infertile females (29%) showed existence of SNP rs10509291 while 49% demonstrated genetic variation of rs12778366. MnSOD and SIRT1 levels were found to be lower in these subjects.

CONCLUSION

The presence of SIRT1 genetic variants (rs10509291 and rs12778366) apparently disturbs the expression of SIRT1 deteriorating mitochondrial antioxidant function within the oocytes, instigating oxidative stress within. Their probable effect on modulating oocyte maturation may be the cause of infertility in females.

Non-Coding RNAs Regulate Placental Trophoblast Function and Participate in Recurrent Abortion

Recurrent spontaneous abortion (RSA) is a serious pregnancy complication with an increasing clinical incidence. The various causes of recurrent abortion are complicated. Developments in genetics, immunology, and cell biology have identified important roles of non-coding RNAs (ncRNAs) in the occurrence and progress of recurrent abortion. NcRNAs can affect the growth, migration, and invasion of placental trophoblasts by regulating cell processes such as the cell cycle, apoptosis, and epithelial-mesenchymal transformation. Therefore, their abnormal expression might lead to the occurrence and development of RSA. NcRNAs include small nuclear RNA (snRNA), small nucleolar RNA (snoRNA), ribosomal RNA (rRNA), transfer, RNA (tRNA), circular RNA (cRNA), and Piwi-interacting RNA (piRNA). In this review, we discuss recent research that focused on the function and mechanism of microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNA (circRNA) in regulating placental trophoblasts. The use of ncRNAs as potential diagnostic and predictive biomarkers in RSA is also discussed to provide future research insights.

Fetomaternal Immune Tolerance: Crucial Mechanisms of Tolerance for Successful Pregnancy in Humans

For many years, the question of how the maternal immune system tolerates the foreign fetus has remained unanswered, and numerous studies have considerably attempted to elucidate underlying mechanisms for fetomaternal tolerance. This review aimed at discussing various significant mechanisms in fetomaternal compatibility. At the fetomaternal interface, in addition to having efficient control against infections, innate and adaptive maternal immune systems selectively prevent fetal rejection. In general, understanding the complex mechanisms of fetomaternal tolerance is critical for immunologic tolerance induction and spontaneous abortion prevention in high-risk populations. Different cells and molecules, such as regulatory T-cells, dendritic cells, decidua cells, IDO, Class I HLA molecules, TGF-β, and IL-10, induce maternal immune tolerance in the fetus in numerous ways. The findings on fetomaternal immune tolerance have remained controversial and require further research.

The potential therapeutic effects of curcumin on pregnancy complications: Novel insights into reproductive medicine

Pregnancy complications including preeclampsia, preterm birth, intrauterine growth restriction, and gestational diabetes are the main adverse reproductive outcomes. Excessive inflammation and oxidative stress play crucial roles in the pathogenesis of pregnancy disorders. Curcumin, the main polyphenolic compound derived from Curcuma longa, is mainly known by its anti-inflammatory and antioxidant properties. There are in vitro and in vivo reports revealing the preventive and ameliorating effects of curcumin against pregnancy complications. Here, we aimed to seek mechanisms underlying the modulatory effects of curcumin on dysregulated inflammatory and oxidative responses in various pregnancy complications.

Review of psychological stress on oocyte and early embryonic development in female mice

Psychological stress can cause adverse health effects in animals and humans. Accumulating evidence suggests that psychological stress in female mice is associated with ovarian developmental abnormalities accompanied by follicle and oocyte defects. Oocyte and early embryonic development are impaired in mice facing psychological stress, likely resulting from hormone signalling disorders, reactive oxygen species (ROS) accumulation and alterations in epigenetic modifications, which are primarily mediated by the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-ovarian (HPO) axes. The present evidence suggests that psychological stress is increasingly becoming the most common causative factor for female subfertility. Here, we review recent progress on the impact of psychological stress on female reproduction, particularly for oocyte and early embryonic development in female mice. This review highlights the connection between psychological stress and reproductive health and provides novel insight on human subfertility.

Association of bisphenol A or bisphenol S exposure with oxidative stress and immune disturbance among unexplained recurrent spontaneous abortion women

Human exposure to environmental chemicals might play a role in the pathogenesis of unexplained recurrent spontaneous abortion (URSA). Bisphenol A (BPA) and bisphenol S (BPS) have been suggested to affect reproductive health. However, the mechanism remains unclear. To explore the association between BPA and BPS exposure and oxidative stress and immune homeostasis, we conducted a cross-sectional study and revealed BPA and BPS levels in relation to these two factors which were supposed to be implicated in miscarriage. 111 URSA patients were recruited and we analyzed urinary BPA and BPS concentrations, oxidative stress biomarkers (8-hydroxydeoxyguanosine and 8-isoprostane) and serum immune balance biomarkers (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, TNF-α, TGF-β and IFN-γ). Multivariable linear regression models were used to evaluate the correlation between bisphenols exposure and outcome biomarkers. After adjustment for age, BMI, menstrual cycle, and parity history, creatinine-adjusted BPA was significantly associated with increases in 8-isoprostane (β = 0.74, 95% CI = 0.07, 1.41; p = 0.031) and IFN-γ (β = 0.18, 95% CI = 0.00, 0.36; p = 0.046). No statistical correlation between BPS and biomarkers of oxidative stress or immune balance was observed when all participants were analyzed. Further analysis revealed that in the subgroup of BPS > limit of detection (0.01 ng/ml), creatinine-adjusted BPS was significantly associated with increases in IL-10 (β = 0.22, 95% CI = 0.00, 0.45; p = 0.048). Our findings suggested that BPA and BPS exposure might be related to oxidative stress and immune imbalance in URSA patients. Overall, our work might suggest potential pathogenic and aetiological associations among the bisphenols, biomarkers and URSA, which offers hypotheses for further studies.

Controlling chronic low-grade inflammation to improve follicle development and survival

Chronic low-grade inflammation is one cause of follicle development disturbance. Chronic inflammation exists in pathological conditions such as premature ovarian failure, physiological aging of the ovaries, and polycystic ovary syndrome. Inflammation of the whole body can affect oocytes via the follicle microenvironment, oxidative stress, and GM-CSF. Many substances without toxic side-effects extracted from natural organisms have gradually gained researchers' attention. Recently, chitosan oligosaccharide, resveratrol, anthocyanin, and melatonin have been found to contribute to an improvement in inflammation. This review discusses the interrelationships between chronic low-grade inflammation and follicle development, the underlying mechanisms, and methods that may improve follicle development by controlling the level of chronic low-grade inflammation.

Antioxidants and Oxidative Stress: Focus in Obese Pregnancies

The prevalence of obesity in women of childbearing age around the globe has dramatically increased in the last decades. Obesity is characterized by a low-state chronic inflammation, metabolism impairment and oxidative stress, among other pathological changes. Getting pregnant in this situation involves that gestation will occur in an unhealthy environment, that can potentially jeopardize both maternal and fetal health. In this review, we analyze the role of maternal obesity-induced oxidative stress as a risk factor to develop adverse outcomes during gestation, including reduced fertility, spontaneous abortion, teratogenesis, preeclampsia, and intrauterine growth restriction. Evidences of macromolecule oxidation increase in reactive oxygen species generation and antioxidant defense alterations are commonly described in maternal and fetal tissues. Thus, antioxidant supplementation become an interesting prophylactic and therapeutic tool, that yields positive results in cellular, and animal models. However, the results from most meta-analysis studying the effect of these therapies in complicated gestations in humans are not really encouraging. It is still to be analyzed whether these therapies could work if applied to cohorts of patients at a high risk, such as those with low concentration of antioxidants or obese pregnant women.

Oxidative Stress in Preeclampsia and Placental Diseases

Preeclampsia is a persistent hypertensive gestational disease characterized by high blood pressure and proteinuria, which presents from the second trimester of pregnancy. At the cellular level, preeclampsia has largely been associated with the release of free radicals by the placenta. Placenta-borne oxidative and nitrosative stresses are even sometimes considered as the major molecular determinants of the maternal disease. In this review, we present the recent literature evaluating free radical production in both normal and pathological placentas (including preeclampsia and other major pregnancy diseases), in humans and animal models. We then assess the putative effects of these free radicals on the placenta and maternal endothelium. This analysis was conducted with regard to recent papers and possible therapeutic avenues.

Monotropein promotes angiogenesis and inhibits oxidative stress-induced autophagy in endothelial progenitor cells to accelerate wound healing

Attenuating oxidative stress‐induced damage and promoting endothelial progenitor cell (EPC) differentiation are critical for ischaemic injuries. We suggested monotropein (Mtp), a bioactive constituent used in traditional Chinese medicine, can inhibit oxidative stress‐induced mitochondrial dysfunction and stimulate bone marrow‐derived EPC (BM‐EPC) differentiation. Results showed Mtp significantly elevated migration and tube formation of BM‐EPCs and prevented tert‐butyl hydroperoxide (TBHP)‐induced programmed cell death through apoptosis and autophagy by reducing intracellular reactive oxygen species release and restoring mitochondrial membrane potential, which may be mediated viamTOR/p70S6K/4EBP1 and AMPK phosphorylation. Moreover, Mtp accelerated wound healing in rats, as indicated by reduced healing times, decreased macrophage infiltration and increased blood vessel formation. In summary, Mtp promoted mobilization and differentiation of BM‐EPCs and protected against apoptosis and autophagy by suppressing the AMPK/mTOR pathway, improving wound healing in vivo. This study revealed that Mtp is a potential therapeutic for endothelial injury‐related wounds.

Chemokine (C-C motif) ligand-2 (CCL2) and oxidative stress markers in recurrent pregnancy loss and repeated implantation failure

PURPOSE

The main purpose of this study is to evaluate the inflammatory response and oxidative stress together in the cases of recurrent pregnancy loss (RPL) and repeated implantation failure (RIF).

METHODS

This is a cross-sectional study conducted to compare infertile patients who have RIF and patients with RPL histories in terms of CCL2, TAS, TOS, and OSI. To this end, two study groups were formed by primary-infertile women with RIF history and women with nulliparous RPL history who consulted a university hospital between 2014 and 2016, and a control group was formed by multiparous women who had no pregnancy loss. With 30 women in each group, 90 women in total were included in the study. CCL2, TAS, and TOS blood levels were measured and oxidative stress index was calculated in all participants.

RESULTS

The patients with RPL and RIF had higher levels of CCL2 than those in the control group. The TOS, TAS, and OSI levels did not differ in RPL and RIF groups from the control group. No statistically significant relationship was found between CCL2 and the TOS, TAS, and OSI values.

CONCLUSIONS

Oxidative stress markers in the pregestational period did not have a predictive value in the RPL and RIF. CCL2 might be useful in risk prediction.

Inverse relationship between vitamin D levels and platelet indices in Korean adults

BACKGROUND AND AIMS

Vitamin D deficiency and increased platelet indices are associated with increased rate or risk of several diseases such as cardiovascular disease and metabolic syndrome, respectively. We investigated whether vitamin D deficiency is associated with increased platelet count (PC) and mean platelet volume (MPV).

METHODS AND RESULTS

The study included 3190 subjects older than 20 years. Subjects were divided into three groups based on their vitamin D levels: vitamin D deficiency (<10.0 ng/ml); insufficiency (10-20 ng/ml); and sufficiency (>20.0 ng/ml). The associations between platelet indices and various parameters were analyzed by Pearson's correlation analysis and t-tests. Then, multivariate linear regression analyses were done correcting for associated parameters. PC and MPV showed a negative correlation with vitamin D groups by ANOVA and multiple linear regression. PC was inversely related with vitamin D group after adjusting for sex, age, regular exercise, white blood cell count, total cholesterol, hemoglobin, and creatinine levels (β ± SE = -3.461 ± 1.512, P = 0.022). MPV was also inversely related with vitamin D group after adjusting for regular exercise, hemoglobin level, and total cholesterol level (β ± SE = -0.080 ± 0.026, P = 0.002), and this relationship remained statistically significant after adjusting for regular exercise, hemoglobin level, total cholesterol level, diabetes, hypertension, and body mass index (β ± SE=-0.082 ± 0.026, P = 0.002).

CONCLUSION

PC and MPV are inversely associated with vitamin D levels in adults.

OLR1 and Loxin Expression in PBMCs of Women with a History of Unexplained Recurrent Miscarriage: A Pilot Study

AIMS

The aim of this study was to evaluate the expression of OLR1 and its alternative splicing isoform Loxin in unexplained recurrent miscarriage (uRM).

METHODS

Sixty-three women of reproductive age were recruited and were divided into four groups: 18 pregnant and 23 non-pregnant women with uRM, and 12 pregnant and 10 non-pregnant women with physiological pregnancies. Complementary DNA derived from peripheral blood mononuclear cells (PBMCs) was analyzed by quantitative real-time PCR to evaluate the expression of OLR1 and Loxin. Oxidized low-density lipoproteins (ox-LDLs) were assayed from serum by a commercially available kit.

RESULTS

Pregnant uRM women presented with a higher, though not significant, OLR1/Loxin ratio and a higher ox-LDLs serum level (p ≤ 0.05) compared with pregnant control women. OLR1 and Loxin levels were significantly decreased in non-pregnant uRM women compared with the control (OLR1: 0.00018 vs. 0.00043, p ≤ 0.005; Loxin: 0.00018 vs. 0.00060, p ≤ 0.005, respectively). Loxin expression decreased by about two-thirds (p ≤ 0.005) in pregnant women compared with non-pregnant control women. A higher expression of OLR1 in pregnant women compared with non-pregnant women with uRM (p ≤ 0.05) was observed, but no variation in Loxin expression was observed.

CONCLUSIONS

The results of this study show an association of peripheral OLR1 and Loxin expression levels in uRM women, and they suggest the possible existence of an uncontrolled oxidative stress in these women in the first trimester of pregnancy.

Endogenous reactive oxygen species cause astrocyte defects and neuronal dysfunctions in the hippocampus: a new model for aging brain

The etiology of astrocyte dysfunction is not well understood even though neuronal defects have been extensively studied in a variety of neuronal degenerative diseases. Astrocyte defects could be triggered by the oxidative stress that occurs during physiological aging. Here, we provide evidence that intracellular or mitochondrial reactive oxygen species (ROS) at physiological levels can cause hippocampal (neuronal) dysfunctions. Specifically, we demonstrate that astrocyte defects occur in the hippocampal area of middle‐aged Tet‐mev‐1 mice with the SDHC^V69E mutation. These mice are characterized by chronic oxidative stress. Even though both young adult and middle‐aged Tet‐mev‐1 mice overproduced MitoSOX Red‐detectable mitochondrial ROS compared to age‐matched wild‐type C57BL/6J mice, only young adult Tet‐mev‐1 mice upregulated manganese and copper/zinc superoxide dismutase (Mn‐ and Cu/Zn‐SODs) activities to eliminate the MitoSOX Red‐detectable mitochondrial ROS. In contrast, middle‐aged Tet‐mev‐1 mice accumulated both MitoSOX Red‐detectable mitochondrial ROS and CM‐H₂DCFDA‐detectable intracellular ROS. These ROS levels appeared to be in the physiological range as shown by normal thiol and glutathione disulfide/glutathione concentrations in both young adult and middle‐aged Tet‐mev‐1 mice relative to age‐matched wild‐type C57BL/6J mice. Furthermore, only middle‐aged Tet‐mev‐1 mice showed JNK/SAPK activation and Ca²⁺ overload, particularly in astrocytes. This led to decreasing levels of glial fibrillary acidic protein and S100β in the hippocampal area. Significantly, there were no pathological features such as apoptosis, amyloidosis, and lactic acidosis in neurons and astrocytes. Our findings suggest that the age‐dependent physiologically relevant chronic oxidative stress caused astrocyte defects in mice with impaired mitochondrial electron transport chain functionality.

MicroRNA-16 inhibits feto-maternal angiogenesis and causes recurrent spontaneous abortion by targeting vascular endothelial growth factor

Recurrent spontaneous abortion (RSA) is a common health problem that affects women of reproductive age. Recent studies have indicated that microRNAs are important factors in miscarriage. This study investigated the role of miR-16 in regulating vascular endothelial growth factor (VEGF) expression and the pathogenesis of RSA. In this report, clinical samples revealed that miR-16 expression was significantly elevated in the villi and decidua of RSA patients. In vitro, miR-16 upregulation inhibited human umbilical vein endothelial cell proliferation, migration and tube formation. Conversely, the downregulation of miR-16 reversed these effects. In vivo, we demonstrated that abnormal miR-16 levels affect the weights of the placenta and embryo and the number of progeny and microvascular density, as well as cause recurrent abortions by controlling VEGF expression in pregnant mice. VEGF, a potential target gene of miR-16, was inversely correlated with miR-16 expression in the decidua of clinical samples. Furthermore, the luciferase reporter system demonstrated that miR-16 was found to directly downregulate the expression of VEGF by binding a specific sequence of its 3′-untranslated region (3′UTR). Collectively, these data strongly suggest that miR-16 regulates placental angiogenesis and development by targeting VEGF expression and is involved in the pathogenesis of RSA.

Oxidative stress in pregnancy and reproduction

Oxidative stress is implicated in the pathophysiology of many reproductive complications including infertility, miscarriage, pre-eclampsia, fetal growth restriction and preterm labour. The presence of excess reactive oxygen species can lead to cellular damage of deoxyribonucleic acids, lipids and proteins. Antioxidants protect cells from peroxidation reactions, limiting cellular damage and helping to maintain cellular membrane integrity. There is overwhelming evidence for oxidative stress causing harm in reproduction. However, there is sparse evidence that supplementation with commonly used antioxidants (mostly vitamins C and E) makes any difference in overcoming oxidative stress or reversing disease processes. There may be potential for antioxidant therapy to ameliorate or prevent disease, but this requires a thorough understanding of the mechanism of action and specificity of currently used antioxidants.

Impact of stress on oocyte quality and reproductive outcome

Stress is an important factor that affects physical and mental status of a healthy person disturbing homeostasis of the body. Changes in the lifestyle are one of the major causes that lead to psychological stress. Psychological stress could impact the biology of female reproduction by targeting at the level of ovary, follicle and oocyte. The increased level of stress hormone such as cortisol reduces estradiol production possibly by affecting the granulosa cell functions within the follicle, which results deterioration in oocyte quality. Adaptation of lifestyle behaviours may generate reactive oxygen species (ROS) in the ovary, which further affects female reproduction. Balance between level of ROS and antioxidants within the ovary are important for maintenance of female reproductive health. Physiological level of ROS modulates oocyte functions, while its accumulation leads to oxidative stress (OS). OS triggers apoptosis in majority of germ cells within the ovary and even in ovulated oocytes. Although both mitochondria- as well as death-receptor pathways are involved in oocyte apoptosis, OS-induced mitochondria-mediated pathway plays a major role in the elimination of majority of germ cells from ovary. OS in the follicular fluid deteriorates oocyte quality and reduces reproductive outcome. On the other hand, antioxidants reduce ROS levels and protect against OS-mediated germ cell apoptosis and thereby depletion of germ cells from the ovary. Indeed, OS is one of the major factors that has a direct negative impact on oocyte quality and limits female reproductive outcome in several mammalian species including human.

Oxidative Stress: Placenta Function and Dysfunction

During pregnancy, the placenta is a site of active oxygen metabolism that continuously generates oxidative stress (OS). Overproduction of reactive oxygen species and reactive nitrogen species can destroy normal placental functions. Therefore, the feto-placental unit generates abundant antioxidants to keep OS under control. Properly controlled oxidative species have been proven to serve as indispensable cellular signal messengers by regulating gene expression and downstream cellular activities. OS also plays an important immunoregulatory role during pregnancy. Oxidative disorder and immune disturbances are associated with adverse pregnancy outcomes such as spontaneous abortion, preeclampsia and intrauterine growth restriction. In this review, we introduce recent studies revealing basal functions and regulatory roles of placental OS in metabolism and immunity. The relationships between OS- and pregnancy-related disorders are also discussed.

Sirtuin Functions in Female Fertility: Possible Role in Oxidative Stress and Aging

In search for strategies aimed at preventing oxidative threat to female fertility, a possible role of sirtuins has emerged. Sirtuins (silent information regulator 2 (Sir2) proteins), NAD(+) dependent enzymes with deacetylase and/or mono-ADP-ribosyltransferase activity, are emerging as key antiaging molecules and regulators in many diseases. Recently, a crucial role for SIRT1 and SIRT3, the main components of sirtuin family, as sensors and guardians of the redox state in oocytes, granulosa cells, and early embryos has emerged. In this context, the aim of the present review is to summarize current knowledge from research papers on the role of sirtuins in female fertility with particular emphasis on the impairment of SIRT1 signalling with oocyte aging. On this basis, the authors wish to build up a framework to promote research on the possible role of sirtuins as targets for future strategies for female fertility preservation.