Antioxidant ameliorating effects against H2O2-induced cytotoxicity in primary endometrial cells

The effect of natural polyphenols Resveratrol, Gallic acid, and Kuromanin chloride on human telomerase reverse transcriptase (hTERT) expression in HepG2 hepatocellular carcinoma: role of SIRT1/Nrf2 signaling pathway and oxidative stress

BACKGROUND

There is evidence that low doses or physiological concentrations of certain natural polyphenols enhance the activity of telomerase. However, the precise mechanism by which natural polyphenols regulate telomerase activity remains unclear. Recent research indicates that NF-E2 related factor 2 (Nrf2) and silent information regulator 1 (SIRT1) are involved in human telomerase reverse transcriptase (hTERT) regulation. Thus, in order to better comprehend the mechanism by which polyphenols regulate hTERT, the present study investigated the effects of the natural polyphenols Resveratrol, Gallic acid, and Kuromanin chloride on hTERT, Nrf2, and SIRT1 expression as well as oxidative stress in HepG2 hepatocellular carcinoma.

METHODS

The trypan blue dye exclusion assay was used to assess cell viability. The level of mRNA for hTERT, Nrf2, and SIRT1 was then determined using real-time PCR. A spectrophotometric analysis was conducted to quantify oxidative stress markers.

RESULTS

The results demonstrated that Resveratrol induces the expression of hTERT and the SIRT1/Nrf2 pathway in a dose-dependent manner. Gallic acid at concentrations of 10 and 20 μM also increased the expression of the hTERT and SIRT1/Nrf2 pathway. Furthermore, dose-dependent overexpression of hTERT and Nrf2 was induced by Kuromanin chloride at 10 and 20 µM. Moreover, we found that Resveratrol and Kuromanin chloride ameliorated oxidative stress, whereas Gallic acid exacerbated it.

CONCLUSIONS

This study demonstrates that low doses of polyphenols (Resveratrol, Gallic acid, and Kuromanin chloride) upregulate the expression of the hTERT gene in the HepG2 hepatocellular carcinoma cell line, possibly via induction of the SIRT1/Nrf2 signaling pathway. Therefore, by targeting this pathway or hTERT, the anti-cancer effect of polyphenols can be enhanced.

Oxidative Stress Induces Bovine Endometrial Epithelial Cell Damage through Mitochondria-Dependent Pathways

Simple Summary

Polymorphonuclear neutrophil (PMN) count is the main diagnostic method of bovine endometritis. High neutrophil PMN counts in the endometrium of cows affected by endometritis suggest the involvement of oxidative stress among the causes of impaired fertility. The damage mechanism of oxidative stress on bovine endometrial epithelial cells (BEECs) is still unelucidated. The objective of this experiment was to investigate the relationship between oxidative stress and graded endometritis in dairy uteri and the molecular mechanism of oxidative stress injury to BEECs. Our research showed that there was an imbalance of antioxidant stress in dairy cow uterine with endometritis, oxidative stress damaged dairy cow endometrial epithelial cells through mitochondria-dependent pathways. These findings may provide new insight into the therapeutic target of bovine endometrial cell injury.

Abstract

Bovine endometritis is a mucosal inflammation that is characterized by sustained polymorphonuclear neutrophil (PMN) infiltration. Elevated PMN counts in the uterine discharge of dairy cows affected by endometritis suggest that oxidative stress may be among the causes of impaired fertility due to the condition. Nevertheless, the effects of oxidative stress-mediated endometritis in dairy cows largely remain uninvestigated. Therefore, fresh uterine tissue and uterine discharge samples were collected to diagnose the severity of endometritis according to the numbers of inflammatory cells in the samples. Twenty-six fresh uteri were classified into healthy, mild, moderate, and severe endometritis groups based on hematoxylin and eosin stain characteristics and the percentage of PMNs in discharge. BEECs were treated with graded concentrations of H₂O₂ from 50 μM to 200 μM in vitro as a model to explore the mechanism of oxidative stress during bovine graded endometritis. The expressions of antioxidant stress kinases were detected by quantitative fluorescence PCR to verify the oxidative stress level in uteri with endometritis. Reactive oxygen species were detected by fluorescence microscope, and inflammation-related mRNA expression increased significantly after H₂O₂ stimulation. Moreover, mRNA expression levels of antioxidant oxidative stress-related enzymes (glutathione peroxidase, superoxide dismutase, and catalase) and mitochondrial membrane potential both decreased. Further investigation revealed that expression of the apoptosis regulator Bcl-2/Bax decreased, whereas expression of the mitochondrial apoptosis-related proteins cytochrome c and caspase-3 increased in response to oxidative stress. Our results indicate that an imbalance exists between oxidation and antioxidation during bovine endometritis. Moreover, apoptosis induced in vitro by oxidative stress was characterized by mitochondrial damage in BEECs.

Mast Cell Activation Syndrome in COVID-19 and Female Reproductive Function: Theoretical Background vs. Accumulating Clinical Evidence

Coronavirus disease 2019 (COVID-19), a pandemic disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, can affect almost all systems and organs of the human body, including those responsible for reproductive function in women. The multisystem inflammatory response in COVID-19 shows many analogies with mast cell activation syndrome (MCAS), and MCAS may be an important component in the course of COVID-19. Of note, the female sex hormones estradiol (E2) and progesterone (P4) significantly influence mast cell (MC) behavior. This review presents the importance of MCs and the mediators from their granules in the female reproductive system, including pregnancy, and discusses the mechanism of potential disorders related to MCAS. Then, the available data on COVID-19 in the context of hormonal disorders, the course of endometriosis, female fertility, and the course of pregnancy were compiled to verify intuitively predicted threats. Surprisingly, although COVID-19 hyperinflammation and post-COVID-19 illness may be rooted in MCAS, the available clinical data do not provide grounds for treating this mechanism as significantly increasing the risk of abnormal female reproductive function, including pregnancy. Further studies in the context of post COVID-19 condition (long COVID), where inflammation and a procoagulative state resemble many aspects of MCAS, are needed.

A study of the potential effect of yellow mealworm (Tenebrio molitor) substitution for fish meal on growth, immune and antioxidant capacity in juvenile largemouth bass (Micropterus salmoides)

This study aimed to evaluate the effects of partial replacement of fish meal (FM) with yellow mealworm (Tenebrio molitor, TM) on the growth performance, food utilization and intestinal immune response of juvenile largemouth bass (Micropterus salmoides). Seven diets containing increasing levels of TM (FM substitution) were designed (approximately 0% (0%), 4% (11.1%), 8.1% (22.2%), 12.2% (33.3%), 16.3% (44.4%), 20.4% (55.5%), and 24.5% (66.6%), designated TM0, TM11, TM22, TM33, TM44, TM55, and TM66, respectively). 420 fish were randomly selected and placed in 21 cages (1 m*1 m*1 m, 7 treatments for triplicate, 20 fish per cage). Fish (initial weight 6.25 ± 0.03 g) were fed seven isonitrogenous (47%) and isocaloric (19 MJ kg^-1) diets to satiety twice daily for 8 weeks. Compared to the control group (TM0), TM11 showed no significant difference in the weight gain rate (WGR), specific growth rate (SGR) or feed conversion ratio (FCR), while all other TM inclusion groups presented different degrees of decline. There was no significant difference in the whole-body composition among all groups (P > 0.05). Plasma total protein (TP), triglyceride (TG) and albumin (ALB) contents were significantly decreased in TM55 and TM66 (P < 0.05). The highest plasma aspartate transaminase (AST) activity was observed in TM66 (P < 0.05). TM33, TM44 and TM55 showed the lowest activities of plasma alanine amiotransferase (ALT) and alkaline phosphatase (ALP) (P < 0.05). Moreover, increased mRNA levels of superoxide dismutase (SOD) and catalase (CAT) were measured in the TM11 to TM55 groups, while intestinal SOD activity peaked in TM11 (P < 0.05). With the exception of TM11, the other TM inclusion groups showed significant inhibition of the relative expression of RelA, C3 and TNF-α (P < 0.05). All experimental groups exhibited lower expression of IL-10 than TM0 (P < 0.05). The TM11 group showed significantly upregulated expression of IL-1β and TGF-β (P < 0.05). In addition, TLR2 expression was increased in TM11 and TM22 (P < 0.05). Considering enzyme activities and immune-related gene expression, TM supplementation levels should not exceed 4% (TM11).

Role of prolidase activity and oxidative stress biomarkers in unexplained infertility

OBJECTIVE

Our aim was to explore the significance of serum prolidase enzyme activity and oxidative stress in women with unexplained infertility (UEI).

METHODS

In this case-control study (n = 160; 86 cases; 74 controls) prolidase enzyme activity and total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), and vitamin E were measured in plasma using enzyme-linked immunosorbent assays.

RESULTS

Prolidase enzyme activity and TAS levels were particularly higher in the patient group (P = 0.013, P = 0.001, respectively). Decreased OSI levels were detected in the patient group (P = 0.001). There was a positive relationship of prolidase with vitamin E in both patient and control groups (r = 0.892, P = 0.001, and r = 0.659, P = 0.001, respectively). A positive, but weak, relationship was identified between prolidase activity and TOS levels and also between vitamin E and TOS levels in the UEI group (r = 0.265, P = 0.049, and r = 0.288, P = 0.014, respectively). No association was found between prolidase and TOS levels or between vitamin E and TOS levels in the control group (r = 0.0097, P = 0.527, and r = 0.085, P = 0.610, respectively).

CONCLUSION

Our results showed an association between serum prolidase activity and oxidative stress in UEI patients. Further studies including greater groups are required to show the role of reactive oxygen species in UEI.

Composition and Anti-Toxicity Effects of Cichorium intybus Distillate on Serum Antioxidant Status in Carbon Tetrachloride-Treated Rats

The role of oxidative stress in female fertility is a compelling area for research. According to traditional medicine, Cichorium intybus, known as Kasni, is believed to improve fertility. For this purpose, the effects of C. intybus distillate (CI) on blood antioxidant status were assessed in rats with carbon tetrachloride (CCl4)-induced toxicity. The rats were assigned to four experimental groups of Control, CI, CCl4, and CI+CCl410 (n=10 in each group). The level of antioxidant enzymes, such as glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT), as well as lipid peroxidation and reduced glutathione (GSH) level, were measured in serum samples. In the second part of the study, the antioxidant activity and phytochemical composition of the hydrodistillate of C. intybus aerial parts were determined by DPPH radical scavenging and gas chromatography-mass spectrometry analysis, respectively. The administration of CCl4 decreased the enzyme activities of GPx, GR, and CAT which were significantly ameliorated after CI administration. The decreased level of serum GSH following CCl4 administration was not considerably elevated in the CI+CCl4 group. Furthermore, the level of malondialdehyde in the serum of CI+CCl4 rats was decreased, compared to the CCl4 group. The main compositions of the essential oil from the C. intybus distillate were the antioxidants of Pulegone (8.10%), Piperitenone (7.68%), dihydroactinidiolide (5.0%), and carvone (4.18%). The antioxidant activity of the distillate was obtained at 75&micro;g/l using the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) test. In general, the results of the present study demonstrated that C. intybus distillate, as a safe herbal remedy, can attenuate CCl4-induced oxidative damages via boosting the endogenous antioxidant defense system.

Ameliorating Effects of Natural Antioxidant Compounds on Female Infertility: a Review

The prevalence of female infertility cases has been increasing at a frightening rate, affecting approximately 48 million women across the world. However, oxidative stress has been recognized as one of the main mediators of female infertility by causing various reproductive pathologies in females such as endometriosis, PCOS, preeclampsia, spontaneous abortion, and unexplained infertility. Nowadays, concerned women prefer dietary supplements with antioxidant properties over synthetic drugs as a natural way to lessen the oxidative stress and enhance their fertility. Therefore, the current review is an attempt to explore the efficacy of various natural antioxidant compounds including vitamins, carotenoids, and plant polyphenols and also of some medicinal plants in improving the fertility status of females. Our summarization of recent findings in the current article would pave the way toward the development of new possible antioxidant therapy to treat infertility in females. Natural antioxidant compounds found in fruits, vegetables, and other dietary sources, alone or in combination with other antioxidants, were found to be effective in ameliorating the oxidative stress-mediated infertility problems in both natural and assisted reproductive settings. Numerous medicinal plants showed promising results in averting the various reproductive disorders associated with female infertility, suggesting a plant-based herbal medicine to treat infertility. Although optimum levels of natural antioxidants have shown favorable results, however, their excessive intake may have adverse health impacts. Therefore, larger well-designed, dose-response studies in humans are further warranted to incorporate natural antioxidant compounds into the clinical management of female infertility.

Preclinical study of innovative peptides mimicking the space structure of the α-helix B of erythropoietin

Introduction: The aim of this study was to examine the effectiveness of innovative peptides obtained by addition of polypeptide motifs with antiaggregation activity (Arg-Gly-Asp, Lys-Gly-Asp and Pro-Gly-Pro) to a peptide mimicking the space structure of the α-helix B of erythropoietin pHBSP (Pyr-Glu-Gln-Leu-Glu-Arg-Ala-Leu-Asn-Ser-Ser).

Materials and methods: The cytoprotective activity of innovative peptides mimicking the space structure of the α-helix B of erythropoietin at the doses of 5 μg/ml, 30 μg/ml and 50 μg/ml was studied on human endothelial cell culture in a simulated oxidative stress. An ADMA-like model of preeclampsia was simulated in the experiment. The study was conducted in 260 female Wistar rats, weighing 250–300 g.

Results and discussion: Innovative peptides mimicking the space structure of the α-helix B of erythropoietin retain their cytoprotective activity in a simulated oxidative stress in HUVEC cell culture at the doses of 5 μg/ml, 30 μg/ml, and 50 μg/ml. The compounds with laboratory codes P-αB1 and P-αB3 had the most pronounced cytoprotective activity. Administration of N-nitro-L-arginine-methyl ether to pregnant females for 7 days causes the morphofunctional changes similar to clinical changes in preeclampsia. The innovative peptide under laboratory code P-αB4 at the dose of 50 μg/kg mimicking the space structure of the α-helix B of erythropoietin shows the most pronounced protective properties.

Conclusion: Innovative peptides mimicking the space structure of the α-helix B of erythropoietin have a pronounced positive influence on the morphofunctional disorders in animals with ADMA-like preeclampsia.

miR‑455 targets FABP4 to protect human endometrial stromal cells from cytotoxicity induced by hydrogen peroxide

Oxidative stress and dysregulation of antioxidant systems are associated with various complications in pregnancy. Endometriosis is a common gynecologic disease that affects women of reproductive age. Recent studies have indicated that oxidative stress may be involved in the pathophysiology of endometriosis. It has been reported that microRNAs can regulate the cellular response to oxidative stress, and mounting evidence indicates that fatty acid binding protein 4 (FABP4) plays an essential role in the regulation of systemic redox capacity. In the present study, we demonstrated that miR-455 is a putative FABP4-targeting miRNA. A luciferase activity assay revealed that miR-455 can successfully bind to the 3′-UTR of FABP4. Overexpression of miR-455 led to the downregulation of FABP4 at both the mRNA and protein levels in a human endometrial stromal cell line. Then, the roles of miR-455 and FABP4 in oxidative stress induced by hydrogen peroxide (H₂O₂) in human endometrial stromal cells were examined. We found that ectopic expression of miR-455 protected cells from damage caused by H₂O₂. Further investigation found that forced expression of miR-455 reduced the level of reactive oxygen species (ROS) and malondialdehyde (MDA), while the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were promoted. Silencing of FABP4 also generated cytoprotective effects against H₂O₂ in human endometrial stromal cells. Moreover, overexpression FABP4 abrogated the miR-455-mediated antioxidative stress effects in cells. Taken together, we propose that miR-455 protects human endometrial stromal cells from oxidative stress at least partly via regulation of FABP4.

Nicotine-Induced Oxidative Stress in Human Primary Endometrial Cells

Nicotine is a major component of tobacco plants and is responsible for the development of reproductive problems in smokers. Nicotine has been recognized to result in oxidative stress by inducing the generation of reactive oxygen species (ROS) in some parts of female reproductive system, but the effect of nicotine on endometrium that plays an important role in reproductive biology stays unexplored. The aim of this work was to clarify the direct effects of nicotine administration on the antioxidant defense system and lipid peroxidation in human endometrial cells. Human endometrial stromal primary cells were treated with nicotine (0, 10−11, 10−8, and 10−6 M) for 24 hours. On nicotine administration, the endometrial cells were associated with a decrease in antioxidant defense markers such as Glutathione (GSH) level, glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT) enzymes activity and higher levels of malondialdehyde (MDA) in a dose-dependent manner when compared to the control. We concluded that nicotine as a pro-oxidant affects the oxidative state of the endometrial cells.