Free radicals, reactive oxygen species, oxidative stress and its classification

Oxidative stress in Wernicke's encephalopathy

Wernicke's encephalopathy (WE) is a severe life-threatening disease that occurs due to vitamin B1 (thiamine) deficiency (TD). It is characterized by acute mental disorder, ataxia, and ophthalmoplegia. TD occurs because of the following reasons: insufficient intake, increased demand, and long-term drinking due to corresponding organ damage or failure. Recent studies showed that oxidative stress (OS) can damage organs and cause TD in the brain, which further leads to neurodegenerative diseases, such as WE. In this review, we discuss the effects of TD caused by OS on multiple organ systems, including the liver, intestines, and brain in WE. We believe that strengthening the human antioxidant system and reducing TD can effectively treat WE.

Recent progress of oxidative stress associated biomarker detection

Oxidative stress denotes the imbalance between the generation of reactive oxygen species (ROS) and antioxidant defenses in living organisms, participating in various pathophysiological processes and mediating the occurrence of diseases. Typically, the excessive production of ROS under oxidative stress elicits oxidative modification of biomacromolecules, including lipids, proteins and nucleic acids, leading to cell dysfunction and damage. Therefore, the analysis and detection of oxidative stress-associated biomarkers are of considerable importance to accurately reflect and evaluate the oxidative stress status. This review comprehensively elucidates the recent advances and applications of imaging probes for tracking and detecting oxidative stress-related biomarkers such as lipid peroxidation, and protein and DNA oxidation. The existing challenges and future development directions in this field are also discussed.

Diverse Possibilities of Si-Based Agent, a Unique New Antioxidant

Antioxidant therapy is an effective approach for treating diseases in which oxidative stress is involved in the onset of symptoms. This approach aims to rapidly replenish the antioxidant substances in the body when they are depleted due to excess oxidative stress. Importantly, a supplemented antioxidant must specifically eliminate harmful reactive oxygen species (ROS) without reacting with physiologically beneficial ROS, which are important to the body. In this regard, typically used antioxidant therapies can be effective, but may cause adverse effects due to their lack of specificity. We believe that Si-based agents are epoch-making drugs that can overcome these problems associated with current antioxidative therapy. These agents alleviate the symptoms of oxidative-stress-associated diseases by generating large amounts of the antioxidant hydrogen in the body. Moreover, Si-based agents are expected to be highly effective therapeutic drug candidates because they have anti-inflammatory, anti-apoptotic, and antioxidant effects. In this review, we discuss Si-based agents and their potential future applications in antioxidant therapy. There have been several reports of hydrogen generation from silicon nanoparticles, but unfortunately, none have been approved as pharmaceutical agents. Therefore, we believe that our research into medical applications using Si-based agents is a breakthrough in this research field. The knowledge obtained thus far from animal models of pathology may greatly contribute to the improvement of existing treatment methods and the development of new treatment methods. We hope that this review will further revitalize the research field of antioxidants and lead to the commercialization of Si-based agents.

Evaluation of the effects of e-cigarette aerosol extracts and tobacco cigarette smoke extracts on human gingival epithelial cells

Smoking increases the risk of a number of diseases, including cardiovascular, oral and lung diseases. E-cigarettes are gaining popularity among young people as an alternative to cigarettes, but there is debate over whether they are less harmful to the mouth than e-cigarettes. In this study, human gingival epithelial cells (HGECs) were treated with four commercially available e-cigarette aerosol condensates (ECAC) or commercially available generic cigarette smoke condensates (CSC) with different nicotine concentrations. Cell viability was determined by MTT assay. Cell apoptosis was observed by acridine orange (AO) and Hoechst33258 staining. The levels of type I collagen, matrix metalloproteinase (MMP-1, MMP-3), cyclooxygenase 2 and inflammatory factors were detected by ELISA and RT-PCR. Finally, ROS levels were analyzed by ROS staining. The different effects of CSC and ECAC on HGECs were compared. The results showed that higher nicotine concentration of CS significantly reduced the activity of HGECs. By contrast, all ECAC had no significant effect. The levels of matrix metalloproteinase, COX-2, and inflammatory factors were higher in HGECs treated with CSC than those treated with ECAC. In contrast, the level of type I collagen was higher in HGECs treated with ECAC than those treated with CSC. In conclusion, all four flavors of e-cigarettes were less toxic to HGE cells than tobacco, but further clinical studies are needed to determine whether e-cigarettes are less harmful to oral health than conventional cigarettes.

Application of soil amendments mitigates phytotoxic effects on Solanum melongena L. and Lycopersicon esculentum L. seedlings exposed to chlorpyrifos and dimethoate pesticides

This field study was done to study the effects of pesticides chlorpyrifos and dimethoate singly and in combination with soil amendments like chemical fertilizer (CF), farmyard manure (FM), and 50% CF + 50% FM (CM) on various indices of growth, physio-biochemical parameters of brinjal, and their residual effect in tomato seedlings. As compared to the control, the decrease of 9.5 and 5.5%, 8.9 and 5.0% in fresh weight, dry weight respectively was recorded in the pesticide-only treatment in the brinjal crop. Pesticides when applied in combination with soil amendments depicted the highest growth of 105.4 and 118.2%, 104.1 and 115.1% in pesticides + CF treatment, 72.7 and 85.1%, 68.1 and 78.1% in pesticides + CM treatment, and 64.4 and 74.0%, 62.7 and 65.7% in pesticides + FM treatment compared to control. In tomato seedlings, the pesticides + CF treatment exhibited the lowest growth indices (25.5 and 31.9%, 26.4 and 28.8%) across the combined treatments while pesticide-only treatment depicted minimum growth compared to the control. In the case of photosynthesis rate and antioxidant activity, the combined treatments showed the trend as pesticides + CF > pesticides + CM > pesticides + FM in the brinjal crop; however, the trend became somewhat reversed in the tomato crop. The results indicated that soil-amended practices modulated pesticide-induced damage by upregulating photosynthetic performance, chlorophyll a fluorescence, and antioxidant balancing which might be associated with the mitigation of ROS-induced pesticide toxicity, and the effect was more pronounced with CM. Furthermore, our study was supported by non-metric-multidimensional scaling (NMDS)-constructed ordination plots by showing spatial patterns in different variables. The study might help in taking management decision to design mitigation actions for government and non-government agency at the farmers' level.

Flavored E-cigarette product aerosols induce transformation of human bronchial epithelial cells

OBJECTIVES

E-cigarettes are the most commonly used nicotine containing products among youth. In vitro studies support the potential for e-cigarettes to cause cellular stress in vivo; however, there have been no studies to address whether exposure to e-liquid aerosols can induce cell transformation, a process strongly associated with pre-malignancy. We examined whether weekly exposure of human bronchial epithelial cell (HBEC) lines to e-cigarette aerosols would induce transformation and concomitant changes in gene expression and promoter hypermethylation.

MATERIALS AND METHODS

An aerosol delivery system exposed three HBEC lines to unflavored e-liquid with 1.2% nicotine, 3 flavored products with nicotine, or the Kentucky reference cigarette once a week for 12 weeks. Colony formation in soft agar, RNA-sequencing, and the EPIC Beadchip were used to evaluate transformation, genome-wide expression and methylation changes.

RESULTS

Jamestown e-liquid aerosol induced transformation of HBEC2 and HBEC26, while unflavored and Blue Pucker transformed HBEC26. Cigarette smoke aerosol transformed HBEC4 and HBEC26 at efficiencies up to 3-fold greater than e-liquids. Transformed clones exhibited extensive reprogramming of the transcriptome with common and distinct gene expression changes observed between the cigarette and e-liquids. Transformation by e-liquids induced alterations in canonical pathways implicated in lung cancer that included axonal guidance and NRF2. Gene methylation, while prominent in cigarette-induced transformed clones, also affected hundreds of genes in HBEC2 transformed by Jamestown. Many genes with altered expression or epigenetic-mediated silencing were also affected in lung tumors from smokers.

CONCLUSIONS

These studies show that exposure to e-liquid aerosols can induce a pre-malignant phenotype in lung epithelial cells. While the Food and Drug Administration banned the sale of flavored cartridge-based electric cigarettes, consumers switched to using flavored products through other devices. Our findings clearly support expanding studies to evaluate transformation potency for the major categories of e-liquid flavors to better inform risk from these complex mixtures.

Synergistic action of carvedilol and clomiphene in mitigating the behavioral phenotypes of letrozole-model of PCOS rats by modulating the NRF2/NFKB pathway

INTRODUCTION

Psychiatric and cognitive impairment has been observed in premenopausal women with a hormonal disorder called polycystic ovary syndrome (PCOS). This study aimed to explore the possibility of combining pharmacological agents: Carvedilol and Clomiphene citrate, with antiestrogenic, antioxidant and anti-inflammatory properties in letrozole-induced PCOS rats.

METHODS

PCOS was induced in rats by the administration of letrozole (1 mg/kg) daily for 21 days. They were subsequently divided into four groups, each receiving either the vehicle or Clomiphene citrate (1 mg/kg) or Carvedilol or a combination of Clomiphene citrate and Carvedilol, respectively from days 22-36. Neurobehavioral studies were conducted on day 35 (Elevated plus maze and Y maze) and day 36 (Novel object recognition). The serum levels of the antioxidants Superoxide dismutase, Catalase, Interleukin 1B (IL-1B), and the gene expression of nuclear factor-erythroid factor 2-related factor 2 (Nrf2), Nuclear Factor k-Beta (NFKB), and acetylcholine esterase in the frontal brain homogenate was determined.

RESULT

Both Carvedilol and the combination therapy reversed the anxiety-like behavior, while Clomiphene citrate and the combination therapy ameliorated the spatial and non-spatial memory impairment observed in PCOS rats. Carvedilol, Clomiphene citrate, and the combination therapy increased the serum concentration of SOD and Catalase and decreased the serum concentration of IL-1B. The combination therapy up-regulated the NRF-2, NFKB, and acetylcholine esterase gene expression.

CONCLUSION

Study showed that the combination of carvedilol and clomiphene citrate has anxiolytic potential and improved cognitive functions in PCOS rats. This might have been achieved by carvedilol and clomiphene citrate's ability to modulate the cholinergic system and the Nrf2 pathway while downregulating the NFκB signaling pathway.

5-Aminolevulinic acid combined with ferrous iron ameliorates scrotal heat stress-induced spermatogenic damage by enhancing HO-1 expression

OBJECTIVE

To explore whether 5-Aminolevulinic acid combined with ferrous iron (5-ALA/Fe²⁺) could protect testicular tissues damage of mice subjected to heat stress (HS) and provide its underlying mechanisms.

METHODS

5-ALA/Fe²⁺ was administered intragastrically to mice for 10 days, then exposed to a scrotal heat stress at 43°C for 20 min on third day. Testes were harvested for morphologic and histopathological examination, oxidative stress, apoptosis, heme oxygenase-1 (HO-1) and inflammation detection. The mitogen-activated protein kinases (MAPK) signaling pathway in testis and CD4⁺FoxP3⁺regulatory T (Treg) cells in spleen were also investigated.

RESULTS

Compared to control group, the testis weight decreased and histological damage severed in HS group. Besides, HS also increased the oxidative stress, apoptosis and inflammation in testis. However, these indicators were ameliorated after 5-ALA/Fe²⁺ treatment but deteriorated after receiving ZnPPIX. The expression of HO-1 was increased both in HS group and 5-ALA/Fe²⁺ group. The protein expression levels of MAPK proteins were activated by HS and inhibited by 5-ALA/Fe²⁺. The CD4⁺FoxP3⁺ Treg generation was reduced by HS and increased by 5-ALA/Fe²⁺.

CONCLUSION

In this study, we have demonstrated that 5-ALA/Fe²⁺ ameliorated the spermatogenic damage induced by scrotal heat stress via up-regulating the expression of HO-1 and inhibiting MAPK mediated oxidative stress and apoptosis and inducing CD4⁺Foxp3⁺ Tregs to inhibit the inflammation induced by HS in mice.

Modifications in Ultrastructural Characteristics and Redox Status of Plants under Environmental Stress: A Review

The rate of global environmental change is unprecedented, with climate change causing an increase in the oscillation and intensification of various abiotic stress factors that have negative impacts on crop production. This issue has become an alarming global concern, especially for countries already facing the threat of food insecurity. Abiotic stressors, such as drought, salinity, extreme temperatures, and metal (nanoparticle) toxicities, are recognized as major constraints in agriculture, and are closely associated with the crop yield penalty and losses in food supply. In order to combat abiotic stress, it is important to understand how plant organs adapt to changing conditions, as this can help produce more stress-resistant or stress-tolerant plants. The investigation of plant tissue ultrastructure and subcellular components can provide valuable insights into plant responses to abiotic stress-related stimuli. In particular, the columella cells (statocytes) of the root cap exhibit a unique architecture that is easily recognizable under a transmission electron microscope, making them a useful experimental model for ultrastructural observations. In combination with the assessment of plant oxidative/antioxidative status, both approaches can shed more light on the cellular and molecular mechanisms involved in plant adaptation to environmental cues. This review summarizes life-threatening factors of the changing environment that lead to stress-related damage to plants, with an emphasis on their subcellular components. Additionally, selected plant responses to such conditions in the context of their ability to adapt and survive in a challenging environment are also described.

Protective effects of pumpkin polysaccharide hydrolysates on oxidative stress injury and its potential mechanism - Antioxidant mechanism of pumpkin polysaccharide hydrolysates

Pumpkin polysaccharides (PPe) exhibit multiple bioactive properties, including the ability to reduce blood sugar and lipids. Our prior investigation discovered that hydrolysates (PPe-s) derived from PPe demonstrated stronger antioxidant capabilities than PPe. The objective of the current study was to explore the potential mechanism of PPe-s, utilizing Caenorhabditis elegans and MIN6 cells as models. The results of this investigation revealed that PPe-s exhibited strong scavenging ability towards ABTS⁺ and OH·in vitro. Additionally, PPe-s extended the lifespan of C. elegans under hydrogen peroxide stress (p < 0.05) by upregulating the mRNA expression of daf-16, sod-1, sod-3, and skn-1 (all >1.43-fold, p < 0.05). Furthermore, PPe-s enhanced the proliferation activity of MIN6 cells, induced by alloxan, increased insulin secretion and cAMP levels, and excreted intracellular excessive Ca²⁺ in a concentration-dependent manner. Our study demonstrated that PPe-s upregulated the expression levels of antioxidative-related genes and augmented the antioxidant defense system.

Oxidative Stress, Inflammation and Colorectal Cancer: An Overview

Colorectal cancer (CRC) represents the second leading cause of cancer-related deaths worldwide. The pathogenesis of CRC is a complex multistep process. Among other factors, inflammation and oxidative stress (OS) have been reported to be involved in the initiation and development of CRC. Although OS plays a vital part in the life of all organisms, its long-term effects on the human body may be involved in the development of different chronic diseases, including cancer diseases. Chronic OS can lead to the oxidation of biomolecules (nucleic acids, lipids and proteins) or the activation of inflammatory signaling pathways, resulting in the activation of several transcription factors or the dysregulation of gene and protein expression followed by tumor initiation or cancer cell survival. In addition, it is well known that chronic intestinal diseases such as inflammatory bowel disease (IBD) are associated with an increased risk of cancer, and a link between OS and IBD initiation and progression has been reported. This review focuses on the role of oxidative stress as a causative agent of inflammation in colorectal cancer.

Effects of insulin-like peptide 7 in Bemisia tabaci MED on tomato chlorosis virus transmission

BACKGROUND

Tomato chlorosis virus (ToCV) is a semi-persistent plant virus that is primarily transmitted by the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae). It causes a serious disease that lowers tomato yield. Insulin-like peptide (ILP), an insulin homolog, regulates trehalose metabolism in a variety of insects. In a previous study, we discovered that trehalose metabolism is required for whiteflies to transmit ToCV effectively. Furthermore, transcriptome sequencing revealed that the BtILP7 gene was highly expressed in B. tabaci infected with ToCV. Therefore, the whitefly ILP7 gene may facilitate the transmission of ToCV and be an attractive target for the control of whiteflies and subsequently ToCV.

RESULTS

The ToCV content in B. tabaci MED was found to be correlated with BtILP7 gene expression. Subsequent RNA interference (RNAi) of the BtILP7 gene had a significant impact on B. tabaci MED's trehalose metabolism and reproductive capacity, as well as ability to transmit ToCV.

CONCLUSIONS

These results indicate that the BtILP7 gene was closely related to ToCV transmission by regulating trehalose metabolism and reproduction behavior, thus providing a secure and environmentally friendly management strategy for the control of whiteflies and ToCV-caused disease. © 2022 Society of Chemical Industry.

Association between C-reactive protein-albumin-lymphocyte (CALLY) index and overall survival in patients with colorectal cancer: From the investigation on nutrition status and clinical outcome of common cancers study

Background

Colorectal cancer (CRC) is among the most common malignant cancers worldwide, and its development is influenced by inflammation, nutrition, and the immune status. Therefore, we combined C-reactive protein (CRP), albumin, and lymphocyte, which could reflect above status, to be the CRP-albumin-lymphocyte (CALLY) index, and evaluated its association with overall survival (OS) in patients with CRC.

Methods

The clinicopathological and laboratory characteristics of 1260 patients with CRC were collected from the Investigation on Nutrition Status and Clinical Outcome of Common Cancers (INSCOC) study. Cox regression analysis was performed to assess the association between the CALLY index and OS. A nomogram including sex, age, the CALLY index and TNM stage was constructed. The Concordance Index (C-index) was utilized to evaluate the prognostic value of the CALLY index and classical CRC prognostic factors, such as modified Glasgow prognostic score (mGPS), neutrocyte to lymphocyte ratio (NLR), systemic immune inflammation index (SII), and platelet to lymphocyte ratio (PLR), as well as to assess the prognostic value of the nomogram and TNM stage.

Results

Multivariate Cox regression analyses demonstrated that the CALLY index was independently associated with OS in patients with CRC [Hazard ratio (HR) = 0.91, 95% confidence interval (CI) = 0.87-0.95, P&lt;0.001]. The CALLY index showed the highest prognostic value (C-index = 0.666, 95% CI = 0.638-0.694, P&lt;0.001), followed by mGPS, NLR, SII, and PLR. The nomogram demonstrated higher prognostic value (C-index = 0.784, 95% CI = 0.762-0.807, P&lt;0.001) than the TNM stage.

Conclusion

The CALLY index was independently associated with OS in patients with CRC and showed higher prognostic value than classical CRC prognostic factors. The nomogram could provide more accurate prognostic prediction than TNM stage.

The Role of Oxidative Stress Enhanced by Adiposity in Cardiometabolic Diseases

Cardiometabolic diseases (CMDs), including cardiovascular disease (CVD), metabolic syndrome (MetS), and type 2 diabetes (T2D), are associated with increased morbidity and mortality. The growing prevalence of CVD is mostly attributed to the aging population and common occurrence of risk factors, such as high systolic blood pressure, elevated plasma glucose, and increased body mass index, which led to a global epidemic of obesity, MetS, and T2D. Oxidant–antioxidant balance disorders largely contribute to the pathogenesis and outcomes of CMDs, such as systemic essential hypertension, coronary artery disease, stroke, and MetS. Enhanced and disturbed generation of reactive oxygen species in excess adipose tissue during obesity may lead to increased oxidative stress. Understanding the interplay between adiposity, oxidative stress, and cardiometabolic risks can have translational impacts, leading to the identification of novel effective strategies for reducing the CMDs burden. The present review article is based on extant results from basic and clinical studies and specifically addresses the various aspects associated with oxidant–antioxidant balance disorders in the course of CMDs in subjects with excess adipose tissue accumulation. We aim at giving a comprehensive overview of existing knowledge, knowledge gaps, and future perspectives for further basic and clinical research. We provide insights into both the mechanisms and clinical implications of effects related to the interplay between adiposity and oxidative stress for treating and preventing CMDs. Future basic research and clinical trials are needed to further examine the mechanisms of adiposity-enhanced oxidative stress in CMDs and the efficacy of antioxidant therapies for reducing risk and improving outcome of patients with CMDs.

Evaluation of the Effects of E-Cigarette Aerosol Extracts and Tobacco Cigarette Smoke Extracts on Human Gingival Epithelial Cells

Smoking increases the risk of a number of diseases, including cardiovascular, oral, and lung diseases. E-cigarettes are gaining popularity among young people as an alternative to cigarettes, but there is debate over whether they are less harmful to the mouth than e-cigarettes. In this study, human gingival epithelial cells (HGECs) were treated with four commercially available e-cigarette aerosol condensates (ECAC) or commercially available generic cigarette smoke condensates (CSC) with different nicotine concentrations. Cell viability was determined by MTT assay. Cell apoptosis was observed by acridine orange (AO) and Hoechst33258 staining. The levels of type I collagen, matrix metalloproteinase (MMP-1, MMP-3), cyclooxygenase 2, and inflammatory factors were detected by ELISA and RT-PCR. Finally, ROS levels were analyzed by ROS staining. The different effects of CSC and ECAC on HGECs were compared. The results showed that higher nicotine concentration of CS significantly reduced the activity of HGECs. By contrast, all ECAC had no significant effect. The levels of matrix metalloproteinase, COX-2, and inflammatory factors were higher in HGECs treated with CSC than those treated with ECAC. In contrast, the level of type I collagen was higher in HGECs treated with ECAC than those treated with CSC. In conclusion, all four flavors of e-cigarettes were less toxic to HGE cells than tobacco, but further clinical studies are needed to determine whether e-cigarettes are less harmful to oral health than conventional cigarettes.

Study the antioxidant of Matricaria chamomilla (Chamomile) powder: In vitro and vivo

Oxidative stress is oxidative damage caused by free radicals and reactive oxygen species (ROS). These ROS can cause oxidative damage to cellular components, including membrane lipids, receptors, enzymes, proteins, and nucleic acids. It would eventually lead to cell apoptosis and the appearance of certain pathological conditions. This work investigates the antioxidant potentials of chamomile extract in vitro by evaluating the extract activity to scavenge 2,2-Diphenyl-1-picrylhydrazyl (DPPH), also in vivo by investigating its effects on oxidative stress-induced rats by assessing the total oxidant status (TOS) and total antioxidant capacity in the radiation exposed rats with and without the treatment with chamomile extract. The results have shown that chamomile extract contains materials with antioxidant properties. The in vitro analyses have indicated activity to detoxify the DPPH radicals almost as powerful as pure ascorbic acid. Furthermore, rats exposed to electromagnetic radiation have shown a disturbance in the balance of oxidants and antioxidants, in which the levels of TOS were elevated while the levels of TAC were reduced. Chamomile extract has been shown to exhibit a powerful function as an antioxidant in vivo. It has enhanced the antioxidant capacity of rats, reduced their total oxidant status, and protected exposure to radiation. Keywords: Total antioxidant capacity, peach fruit, rats, DPPH, total oxidant status.

Predicting the bioremediation potential of earthworms of different ecotypes through a multi-biomarker approach

Earthworms are attracting the attention of bioremediation research because of their short-term impact on pollutant fate. However, earthworm-assisted bioremediation largely depends on the earthworm sensitivity to target pollutants and its metabolic capacity to break down contaminants. The most studied species in soil bioremediation has been Eisenia fetida, which inhabits the soil surface feeding on decomposing organic residues. Therefore, its bioremediation potential may be limited to organic matter-rich topsoil. We compared the detoxification potential against organophosphate (OP) pesticides of three earthworm species representative of the main ecotypes: epigeic, anecic, and endogeic. Selected biomarkers of pesticide detoxification (esterases, cytochrome P450-dependent monooxygenase, and glutathione S-transferase) and oxidative homeostasis (total antioxidant capacity, glutathione levels, and glutathione reductase [GR] and catalase activities) were measured in the muscle wall and gastrointestinal tract of E. fetida (epigeic), Lumbricus terrestris (anecic) and Aporrectodea caliginosa (endogeic). Our results show that L. terrestris was the most suitable species to bioremediate OP-contaminated soil for the following reasons: 1) Gut carboxylesterase (CbE) activity of L. terrestris was higher than that of E. fetida, whereas muscle CbE activity was more sensitivity to OP inhibition than that of E. fetida, which means a high capacity to inactivate the toxic oxon metabolites of OPs. 2) Muscle and gut phosphotriesterase activities were significantly higher in L. terrestris than in the other species. 3) Enzymatic (catalase and GR) and molecular mechanisms of free radical inactivation (glutathione) were 3- to 4-fold higher in L. terrestris concerning E. fetida and A. caliginosa, which reveals a higher potential to keep the cellular oxidative homeostasis against reactive metabolites formed during OP metabolism. Together with biological and ecological traits, these toxicological traits suggest L. terrestris a better candidate for soil bioremediation than epigeic earthworms.

miR-4478 Accelerates Nucleus Pulposus Cells Apoptosis Induced by Oxidative Stress by Targeting MTH1

OBJECTIVES

Low back pain is the leading cause of disability in the elderly population and is strongly associated with intervertebral disk degeneration (IVDD). However, the precise molecular mechanisms regulating IVDD remain elusive. This study aimed to investigate the role of differentially expressed miRNAs in the pathogenesis of IVDD.

MATERIALS AND METHODS

We analyzed miRNA microarray datasets to identify differentially expressed miRNAs in IVDD progression and conducted quantitative real-time polymerase chain reaction and fluorescence in situ hybridization analysis to further confirm the differential expression of miR-4478 in nucleus pulposus (NP) tissues of patients diagnosed with IVDD. Using public databases of miRNA-mRNA interactions, we predicted the target genes of miR-4478, and subsequent flow cytometry and western blot analyses demonstrated the effect of MTH1 in H 2 O 2 -induced nucleus pulposus cells (NPCs) apoptosis. Finally, miR-4478 inhibitor was injected into NP tissues of the IVDD mouse model to explore the effect of miR-4478 in vivo.

RESULTS

miR-4478 was upregulated in NP tissues from IVDD patients. Silencing of miR-4478 inhibits H 2 O 2 -induced NPCs apoptosis. MTH1 was identified as a target gene for miR-4478, and miR-4478 regulates H 2 O 2 -induced NPCs apoptosis by modulating MTH1. In addition, downregulation of miR-4478 alleviated IVDD in a mouse model.

CONCLUSIONS

In summary, our study provides evidence that miR-4478 may aggravate IVDD through its target gene MTH1 by accelerating oxidative stress in NPCs and demonstrates that miR-4478 has therapeutic potential in IVDD treatment.

Ameliorative effects of propolis upon reproductive toxicity in males

Propolis is a sticky natural product produced by honeybees. Research studies have discussed the effectiveness of propolis, directly or indirectly, for ameliorating reproductive toxicity in males; however, this research has not yet been reviewed. The current paper presents an integrative summary of all research studies in Scopus and PubMed that investigated the effects of propolis on semen quality, and hence on male fertility, in conditions of reproductive toxicity. The consensus indicates that propolis ameliorates reproductive toxicity and enhances semen quality in vivo in test animals. These effects may be attributable to the ability of propolis to reduce testicular oxidative damage, enhance testicular antioxidant defense mechanisms, increase nitric oxide production, reduce testicular apoptotic injury, and boost testosterone production. However, to generalize these effects in humans would require further research.

Polysaccharides from Phellinus linteus: A systematic review of their extractions, purifications, structures and functions

Phellinus linteus (P. linteus) is a famous Chinese medicine and has a long history in China. In recent years, P. linteus polysaccharides (PLPs) have attracted extensive attention because of their biological activities such as anti-bacteria, anti-aging, anti-oxidation, anti-inflammation, anti-tumor, hepatoprotective effect and hypoglycemic effect. In this review, we systemically summarized the advances in extractions, purifications and structural characterizations of PLPs, and also analyzed their biological functions and molecular mechanisms. Meanwhile, the structure-activity relationships of PLPs are closely related to their anti-oxidation and anti-tumor activities. So far, the applications of PLPs are still very limited, further exploring structure-activity relationships, biological functions and their mechanisms of PLPs will promote to develop functional foods.

Combined effect of microplastic, salinomycin and heating on Unio tumidus

Microplastic (MP) and heating (T) suspected to modulate biological effects of aquatic contaminants. Salinomycin (Sal) is veterinary antibiotic and anticancer agent. The goal of this study was to examine the multistress effect of MP, Sal and T on the bioindicator bivalve mollusc. The Unio tumidus were treated with MP (1 mg L^-1), Sal (0.6 µg L^-1), their combination under 18° C (Mix) and 25° C (MixT) for 14 days. The digestive glands were analyzed. MP and Sal did not cause changes of Mn- and Cu,Zn-SOD, lipid peroxidation and Cyp-450-depended EROD levels, whereas catalase, GST and protein carbonyls (Sal-group) increased compared to control. In the Mix-group, enzymes, particularly EROD and GST (by 34% and 115% respectively) were up-regulated. However, in the MixT-group, they were corresponding to control or lesser (EROD, catalase). Our findings emphasize the need to take into account multistress interactions in the MP environmental risk assessment.

Molecular mechanisms of hepatotoxicity induced by compounds occurring in Evodiae Fructus

Evodiae Fructus (EF) is a common herbal medicine with thousands of years of medicinal history in China, which has been demonstrated with many promising pharmacological effects on cancer, cardiovascular diseases and Alzheimer's disease. However, there have been increasing reports of hepatotoxicity associated with EF consumption. Unfortunately, in a long term, many implicit constituents of EF as well as their toxic mechanisms remain poorly understood. Recently, metabolic activation of hepatotoxic compounds of EF to generate reactive metabolites (RMs) has been implicated. Herein, we capture metabolic reactions relevant to hepatotoxicity of these compounds. Initially, catalyzed by the hepatic cytochrome P450 enzymes (CYP450s), the hepatotoxic compounds of EF are oxidized to generate RMs. Subsequently, the highly electrophilic RMs could react with nucleophilic groups contained in biomolecules, such as hepatic proteins, enzymes, and nucleic acids to form conjugates and/or adducts, leading to a sequence of toxicological consequences. In addition, currently proposed biological pathogenesis, including oxidative stress, mitochondrial damage and dysfunction, endoplasmic reticulum (ER) stress, hepatic metabolism disorder, and cell apoptosis are represented. In short, this review updates the knowledge on the pathways of metabolic activation of seven hepatotoxic compounds of EF and provides considerable insights into the relevance of proposed molecular hepatotoxicity mechanisms from a biochemical standpoint, for the purpose of providing a theoretical guideline for the rational application of EF in clinics.

Mitochondrial Open Reading Frame of the 12S rRNA Type-c: Potential Therapeutic Candidate in Retinal Diseases

Mitochondrial open reading frame of the 12S rRNA type-c (MOTS-c) is the most unearthed peptide encoded by mitochondrial DNA (mtDNA). It is an important regulator of the nuclear genome during times of stress because it promotes an adaptive stress response to maintain cellular homeostasis. Identifying MOTS-c specific binding partners may aid in deciphering the complex web of mitochondrial and nuclear-encoded signals. Mitochondrial damage and dysfunction have been linked to aging and the accelerated cell death associated with many types of retinal degenerations. Furthermore, research on MOTS-c ability to revive oxidatively stressed RPE cells has revealed a significant protective role for the molecule. Evidence suggests that senescent cells play a role in the development of age-related retinal disorders. This review examines the links between MOTS-c, mitochondria, and age-related diseases of the retina. Moreover, the untapped potential of MOTS-c as a treatment for glaucoma, diabetic retinopathy, and age-related macular degeneration is reviewed.

Early Detection Is the Best Prevention-Characterization of Oxidative Stress in Diabetes Mellitus and Its Consequences on the Cardiovascular System

Previous studies demonstrated an important role of oxidative stress in the pathogenesis of cardiovascular disease (CVD) in diabetic patients due to hyperglycemia. CVD remains the leading cause of premature death in the western world. Therefore, diabetes mellitus-associated oxidative stress and subsequent inflammation should be recognized at the earliest possible stage to start with the appropriate treatment before the onset of the cardiovascular sequelae such as arterial hypertension or coronary artery disease (CAD). The pathophysiology comprises increased reactive oxygen and nitrogen species (RONS) production by enzymatic and non-enzymatic sources, e.g., mitochondria, an uncoupled nitric oxide synthase, xanthine oxidase, and the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX). Considering that RONS originate from different cellular mechanisms in separate cellular compartments, adequate, sensitive, and compartment-specific methods for their quantification are crucial for early detection. In this review, we provide an overview of these methods with important information for early, appropriate, and effective treatment of these patients and their cardiovascular sequelae.

Antenatal and Postnatal Sequelae of Oxidative Stress in Preterm Infants: A Narrative Review Targeting Pathophysiological Mechanisms

The detrimental effects of oxidative stress (OS) can start as early as after conception. A growing body of evidence has shown the pivotal role of OS in the development of several pathological conditions during the neonatal period, which have been therefore defined as OS-related neonatal diseases. Due to the physiological immaturity of their antioxidant defenses and to the enhanced antenatal and postnatal exposure to free radicals, preterm infants are particularly susceptible to oxidative damage, and several pathophysiological cascades involved in the development of prematurity-related complications are tightly related to OS. This narrative review aims to provide a detailed overview of the OS-related pathophysiological mechanisms that contribute to the main OS-related diseases during pregnancy and in the early postnatal period in the preterm population. Particularly, focus has been placed on pregnancy disorders typically associated with iatrogenic or spontaneous preterm birth, such as intrauterine growth restriction, pre-eclampsia, gestational diabetes, chorioamnionitis, and on specific postnatal complications for which the role of OS has been largely ascertained (e.g., respiratory distress, bronchopulmonary dysplasia, retinopathy of prematurity, periventricular leukomalacia, necrotizing enterocolitis, neonatal sepsis). Knowledge of the underlying pathophysiological mechanisms may increase awareness on potential strategies aimed at preventing the development of these conditions or at reducing the ensuing clinical burden.

N-Feruloyl Serotonin Attenuates Neuronal Oxidative Stress and Apoptosis in Aβ25-35-Treated Human Neuroblastoma SH-SY5Y Cells

Amyloid-beta (Aβ) aggregation and deposition have been identified as a critical feature in the pathology of Alzheimer's disease (AD), with a series of functional alterations including neuronal oxidative stress and apoptosis. N-feruloyl serotonin (FS) is a plant-derived component that exerts antioxidant activity. This study investigated the protective effects of FS on Aβ_25-35-treated neuronal damage by regulation of oxidative stress and apoptosis in human neuroblastoma SH-SY5Y cells. The radical scavenging activities increased with the concentration of FS, exhibiting in vitro antioxidant activity. The Aβ_25-35-treated SH-SY5Y cells exerted neuronal cell injury by decreased cell viability and elevated reactive oxygen species, but that was recovered by FS treatment. In addition, treatment of FS increased anti-apoptotic factor B-cell lymphoma protein 2 (Bcl-2) and decreased the pro-apoptotic factor Bcl-2-associated X protein. The FS attenuated Aβ-stimulated neuronal apoptosis by regulations of mitogen-activated protein kinase signaling pathways. Moreover, activated CREB-BDNF signaling was observed by the treatment of FS in Aβ_25-35-induced SH-SY5Y cells. These results demonstrate that FS shows potential neuroprotective effects on Aβ_25-35-induced neuronal damage by attenuation of oxidative stress and apoptosis, and suggest that FS may be considered a promising candidate for the treatment of AD.

Trends and hotspots for European Journal of Medicinal Chemistry: A bibliometric study

European Journal of Medicinal Chemistry (EJMC) has been around for a long time and has gained broad interest from the various individuals working in the field. However, there is no bibliometric analysis on the publications of EJMC to thoroughly assess the scientific output and current status systematically. Therefore, the study was conducted to analyze the various publications of EJMC from 1987 to 2022 to improve their quality. A total of 13,386 papers were retrieved, with the number of publications increasing yearly. Based on the multiple indicators of bibliometrics, the highest impact countries, institutions, authors and representative literature were identified, and visualization networks were constructed using VOSviewer. Keyword co-occurrence analysis reveals a gradual shift from phenotypic drug discovery to target-based drug discovery in the EJMC theme change. Moreover, further discussion of the keyword clustering results is provided to support researchers in defining the scope of their research topics and planning their research directions. At this stage, there is a greater focus on developing antitumor and oxidative stress-related drugs than on the earlier anti-infective activities. In future studies, the main research directions are tumor multidrug resistance, oxidative stress, and dual inhibitors.

Nanoantioxidant Materials: Nanoengineering Inspired by Nature

Oxidants are very active compounds that can cause damage to biological systems under specific environmental conditions. One effective way to counterbalance these adverse effects is the use of anti-oxidants. At low concentrations, an antioxidant is defined as a compound that can delay, control, or prevent an oxidative process. Antioxidants exist in plants, soil, and minerals; therefore, nature is a rich source of natural antioxidants, such as tocopherols and polyphenols. In nature, antioxidants perform in tandem with their bio-environment, which may tune their activity and protect them from degradation. In vitro use of antioxidants, i.e., out of their biomatrix, may encounter several drawbacks, such as auto-oxidation and polymerization. Artificial nanoantioxidants can be developed via surface modification of a nanoparticle with an antioxidant that can be either natural or synthetic, directly mimicking a natural antioxidant system. In this direction, state-of-the-art nanotechnology has been extensively incorporated to overcome inherent drawbacks encountered in vitro use of antioxidants, i.e., out of their biomatrix, and facilitate the production and use of antioxidants on a larger scale. Biomimetic nanoengineering has been adopted to optimize bio-medical antioxidant systems to improve stability, control release, enhance targeted administration, and overcome toxicity and biocompatibility issues. Focusing on biotechnological sciences, this review highlights the importance of nanoengineering in developing effective antioxidant structures and comparing the effectiveness of different nanoengineering methods. Additionally, this study gathers and clarifies the different antioxidant mechanisms reported in the literature and provides a clear picture of the existing evaluation methods, which can provide vital insights into bio-medical applications.

Cytoprotective and genoprotective effects of taxifolin against oxidative damage in HTR-8/SVneo human trophoblast cells

An increase of reactive oxygen species in the placenta and oxidative disbalance has been recognized as a significant factor contributing to pregnancy complications. Dietary intake of food rich in antioxidants during pregnancy could exert a protective role in the prevention of adverse outcomes such as preeclampsia, miscarriage, and others. Flavonoid taxifolin has shown numerous health-promoting effects in a large number of studies conducted on animals, as well as various human cell types in vitro. However, its effects on human placental cells-trophoblasts-have yet to be determined. Therefore, cytoprotective and genoprotective effects of taxifolin on trophoblast cell line HTR-8/SVneo under induced oxidative stress were explored in this study. Cytotoxicity of a range of taxifolin concentrations (1-150 µM) was evaluated using the MTT and crystal violet assays. A model of oxidative stress was achieved by exposing HTR-8/SVneo cells to H2O2. To determine cytoprotective and antigenotoxic effects, the cells were pre-incubated with three concentrations of taxifolin (10, 50, and 100 µM) and then exposed to H2O2. Taxifolin in concentrations of 1, 5, 10, 25, 50, and 100 µM showed no cytotoxic effects on HTR-8/SVneo cells, but 150 µM of taxifolin caused a significant decrease in adherent cell number, as detected by crystal violet assay. Pretreatment with the chosen concentrations of taxifolin showed a significant cytoprotective effect on H2O2-induced cytotoxicity, as determined by the MTT assay. Furthermore, taxifolin showed a significant reduction in H2O2-induced DNA damage, measured by comet assay. This study showed protective effects of taxifolin on human trophoblast cells exposed to oxidative damage. Further studies are needed to explore the underlying mechanisms.

Molecular and biochemical responses to tributyltin (TBT) exposure in the American oyster: Triggers of stress-induced oxidative DNA damage and prooxidant-antioxidant imbalance in tissues by TBT

Environmental pollution increases due to anthropogenic activities. Toxic chemicals in the environment affect the health of aquatic organisms. Tributyltin (TBT) is a toxic chemical widely used as an antifouling paint on boats, hulls, and ships. The toxic effect of TBT is well documented in aquatic organisms; however, little is known about the effects of TBT on DNA lesions in shellfish. The American oyster (Crassostrea virginica, an edible and commercially important species) is an ideal marine mollusk to examine the effects of TBT exposure on DNA lesions and oxidative/nitrative stress. In this study, we investigated the effects of TBT on 8'-hydroxy-2'-deoxyguanosine (8-OHdG, a biomarker of pro-mutagenic DNA lesion), double-stranded DNA (dsDNA), dinitrophenyl protein (DNP, a biomarker on reactive oxygen species, ROS), 3-nitrotyrosine protein (NTP, a biomarker of reactive nitrogen species, RNS), catalase (CAT, an antioxidant), and acetylcholinesterase (AChE, a cholinergic enzyme) expressions in the gills and digestive glands of oysters. We also analyzed extrapallial (EF) fluid conditions. Immunohistochemical and qRT-PCR results showed that TBT exposure significantly increased 8-OHdG, dsDNA, DNP, NTP, and CAT mRNA and/or protein expressions in the gills and digestive glands. However, AChE mRNA and protein expressions, and EP fluid pH and protein concentrations were decreased in TBT-exposed oysters. Taken together, these results suggest that antifouling biocide-induced production of ROS/RNS results in DNA damage, which may lead to decreased cellular functions in oysters. To the best of our knowledge, the present study provides the first molecular/biochemical evidence that TBT exposure results in oxidative/nitrative stress and DNA lesions in oysters.

Nanoparticles assisted regulation of oxidative stress and antioxidant enzyme system in plants under salt stress: A review

The global biomass production from agricultural farmlands is facing severe constraints from abiotic stresses like soil salinization. Salinity-mediated stress triggered the overproduction of reactive oxygen species (ROS) that may result in oxidative burst in cell organelles and cause cell death in plants. ROS production is regulated by the redox homeostasis that helps in the readjustment of the cellular redox and energy state in plants. All these cellular redox related functions may play a decisive role in adaptation and acclimation to salinity stress in plants. The use of nanotechnology like nanoparticles (NPs) in plant physiology has become the new area of interest as they have potential to trigger the various enzymatic and non-enzymatic antioxidant capabilities of plants under varying salinity levels. Moreover, NPs application under salinity is also being favored due to their unique characteristics compared to traditional phytohormones, amino acids, nutrients, and organic osmolytes. Therefore, this article emphasized the core response of plants to acclimate the challenges of salt stress through auxiliary functions of ROS, antioxidant defense system and redox homeostasis. Furthermore, the role of different types of NPs mediated changes in biochemical, proteomic, and genetic expressions of plants under salt stress have been discussed. This article also discussed the potential limitations of NPs adoption in crop production especially under environmental stresses.

Commentary: On the merit of an early contributor of the "Preparation for Oxidative Stress" (POS) theory

This commentary acknowledges the contributions of the Ukrainian biologist, Dr. Volodymyr Lushchak, to the understanding of the physiological adaptive strategy called "Preparation for Oxidative Stress" (POS). In the 1990s, various studies revealed that activities of antioxidant enzymes rose in animals under hypometabolic conditions. These timely observations allowed scientists to propose that this increase could prepare animals for reoxygenation events following the release of oxygen restriction, but in doing so, would trigger oxidative damage, hence the use of the term "preparation". Over next 25 years, the phenomenon was described in detail in more than one hundred studies of animals under conditions of aestivation, hypoxia/anoxia, freezing, severe dehydration, ultraviolet exposure, air exposure of water-breathing animals, salinity stress, and others. The POS phenomenon remained without a mechanistic explanation until 2013, when it was proposed that a small increase in oxyradical formation during hypoxia exposure (in hypoxia-tolerant animals) could activate redox-sensitive transcription factors that, in turn, would initiate transcription and translation of antioxidant enzymes. Dr. Lushchak, who studied goldfish under severe hypoxia in the 1990s, had actually proposed the increased production of oxyradicals under this condition and concluded that it would lead to an upregulation of antioxidant enzymes, the hallmark of the POS strategy. However, his research partner at the time, Dr. Hermes-Lima, thought the idea did not have sufficient evidence to support it and recommended the removal of this explanation. In those days, the main line of thinking was that increased oxyradical formation under hypoxia was "impossible". So, as it turns out, the ideas of Dr. Lushchak were well ahead of his time. It then took >10 years before the biochemical and molecular mechanisms responsible for triggering the POS response were clarified. In the present article, this fascinating history is described to highlight Dr. Lushchak's contributions and insights about the POS theory.

Mechanisms of action of non-enzymatic antioxidants to control oxidative stress during in vitro follicle growth, oocyte maturation, and embryo development

In vitro follicle growth and oocyte maturation still has a series of limitations, since not all oocytes matured in vitro have the potential to develop in viable embryos. One of the factors associated with low oocyte quality is the generation of reactive oxygen species (ROS) during in vitro culture. Therefore, this review aims to discuss the role of non-enzymatic antioxidants in the control of oxidative stress during in vitro follicular growth, oocyte maturation and embryonic development. A wide variety of non-enzymatic antioxidants (melatonin, resveratrol, L-ascorbic acid, L-carnitine, N-acetyl-cysteine, cysteamine, quercetin, nobiletin, lycopene, acteoside, mogroside V, phycocyanin and laminarin) have been used to supplement culture media. Some of them, like N-acetyl-cysteine, cysteamine, nobiletin and quercetin act by increasing the levels of glutathione (GSH), while melatonin and resveratrol increase the expression of antioxidant enzymes and minimize oocyte oxidative stress. L-ascorbic acid reduces free radicals and reactive oxygen species. Lycopene positively regulates the expression of many antioxidant genes. Additionally, L-carnitine protects DNA against ROS-induced damage, while acteoside and laminarin reduces the expression of proapoptotic genes. Mogrosides increases mitochondrial function and reduces intracellular ROS levels, phycocyanin reduces lipid peroxidation, and lycopene neutralizes the adverse effects of ROS. Thus, it is very important to know their mechanisms of actions, because the combination of two or more antioxidants with different activities has great potential to improve in vitro culture systems.

Pterostilbene Confers Protection against Diquat-Induced Intestinal Damage with Potential Regulation of Redox Status and Ferroptosis in Broiler Chickens

Oxidative stress causes damage to macromolecules, including proteins, DNA, and lipid, and has been recognized as a crucial driver of the onset and progression of several intestinal disorders. Pterostilbene, one of the natural antioxidants, has attracted considerable attention owing to its multiple biological activities. In the present study, we established an oxidative stress model in broiler chickens via injection with diquat to investigate whether pterostilbene could attenuate diquat-induced intestinal damage and reveal the underlying mechanisms. We found that diquat-induced decreases in the activities of superoxide dismutase and glutathione peroxidase and the level of reduced glutathione and the increase in hydrogen peroxide content in plasma and jejunum were significantly alleviated by pterostilbene (P < 0.05). Pterostilbene supplementation also decreased intestinal permeability and jejunal apoptosis rate, improved jejunal villus height and the ratio of villus height to crypt depth, and promoted the transcription and translation of jejunal tight junction proteins occludin and zona occludens 1 in diquat-challenged broilers (P < 0.05). Furthermore, pterostilbene reversed diquat-induced mitochondrial injury in the jejunum, as indicated by the decreased reactive oxygen species level and elevated activities of superoxide dismutase 2 and mitochondrial respiratory complexes (P < 0.05). Importantly, administering pterostilbene maintained iron homeostasis, inhibited lipid peroxidation, and regulated the expression of the markers of ferroptosis in the jejunum of diquat-exposed broilers (P < 0.05). The nuclear factor erythroid 2-related factor 2 signaling pathway in the jejunum of diquat-exposed broilers was also activated by pterostilbene (P < 0.05). In conclusion, our study provides evidence that pterostilbene alleviates diquat-induced intestinal mucosa injury and barrier dysfunction by strengthening antioxidant capacity and regulating ferroptosis of broiler chickens.

The Road to Malignant Cell Transformation after Particulate Matter Exposure: From Oxidative Stress to Genotoxicity

In cells, oxidative stress is an imbalance between the production/accumulation of oxidants and the ability of the antioxidant system to detoxify these reactive products. Reactive oxygen species (ROS), cause multiple cellular damages through their interaction with biomolecules such as lipids, proteins, and DNA. Genotoxic damage caused by oxidative stress has become relevant since it can lead to mutation and play a central role in malignant transformation. The evidence describes chronic oxidative stress as an important factor implicated in all stages of the multistep carcinogenic process: initiation, promotion, and progression. In recent years, ambient air pollution by particulate matter (PM) has been cataloged as a cancer risk factor, increasing the incidence of different types of tumors. Epidemiological and toxicological evidence shows how PM-induced oxidative stress could mediate multiple events oriented to carcinogenesis, such as proliferative signaling, evasion of growth suppressors, resistance to cell death, induction of angiogenesis, and activation of invasion/metastasis pathways. In this review, we summarize the findings regarding the involvement of oxidative and genotoxic mechanisms generated by PM in malignant cell transformation. We also discuss the importance of new approaches oriented to studying the development of tumors associated with PM with more accuracy, pursuing the goal of weighing the impact of oxidative stress and genotoxicity as one of the main mechanisms associated with its carcinogenic potential.

Ocean acidification and seasonal temperature extremes combine to impair the thermal physiology of a sub-Antarctic fish

To predict the potential impacts of climate change on marine organisms, it is critical to understand how multiple stressors constrain the physiology and distribution of species. We evaluated the effects of seasonal changes in seawater temperature and near-future ocean acidification (OA) on organismal and sub-organismal traits associated with the thermal performance of Eleginops maclovinus, a sub-Antarctic notothenioid species with economic importance to sport and artisanal fisheries in southern South America. Juveniles were exposed to mean winter and summer sea surface temperatures (4 and 10 °C) at present-day and near-future pCO₂ levels (~500 and 1800 μatm). After a month, the Critical Thermal maximum and minimum (CTmax, CTmin) of fish were measured using the Critical Thermal Methodology and the aerobic scope of fish was measured based on the difference between their maximal and standard rates determined from intermittent flow respirometry. Lipid peroxidation and the antioxidant capacity were also quantified to estimate the oxidative damage potentially caused to gill and liver tissue. Although CTmax and CTmin were higher in individuals acclimated to summer versus winter temperatures, the increase in CTmax was minimal in juveniles exposed to the near-future compared to present-day pCO₂ levels (there was a significant interaction between temperature and pCO₂ on CTmax). The reduction in the thermal tolerance range under summer temperatures and near-future OA conditions was associated with a reduction in the aerobic scope observed at the elevated pCO₂ level. Moreover, an oxidative stress condition was detected in the gill and liver tissues. Thus, chronic exposure to OA and the current summer temperatures pose limits to the thermal performance of juvenile E. maclovinus at the organismal and sub-organismal levels, making this species vulnerable to projected climate-driven warming.

Catalyst-Free, Room-Temperature Accessible Regioselective Synthesis of Spiroquinolines and Their Antioxidant Study

An efficient, regioselective, and environmentally benign approach was established using the multicomponent reaction-based synthesis of novel antioxidant spiroquinoline derivatives such as spiro[dioxolo[4,5-g]quinoline], spiro[dioxino[2,3-g]quinoline], and spiro[pyrazolo[4,3-f]quinoline] by reaction of aryl aldehyde, Meldrum's acid, and amine derivatives under an additive-free reaction in aqueous ethanol. Here, two asymmetric carbon centers, three new C-C bonds, and one C-N bond are developed in the final motif. This synthetic methodology offers excellent yields with an easy workup procedure, high diastereoselectivity [d.r. >50:1 (cis/trans)], admirable atom economy, and low E-factor values. Synthesized spiro compounds were investigated for their in vitro antioxidant activity by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays. In the ABTS radical scavenging assay, compounds 4d, 4f, and 4l exhibit excellent potency, and in the DPPH radical scavenging assay, compounds 4a, 4d, 4f, and 4g, exhibit excellent potency.

Does Oxidative Stress Along with Dysbiosis Participate in the Pathogenesis of Asthma in the Obese?

The most important environmental factor that can play a key role in the development of asthma in the obese is overproduction of reactive oxygen species (ROS). The aim of the study was to examine changes in the concentration of oxidative stress parameters in the lungs, bronchoalveolar lavage (BAL) fluid and blood of mice in models of asthma or/and obesity caused by high-fat diet (HFD). The concentrations of 4-HNE and isoprostanes in the lungs of the animals were measured. BAL fluid levels of hydrogen peroxide were marked. Additionally, thiobarbituric acid reactive substances (TBARS) and ferric reducing ability of plasma (FRAP) were used as biomarkers of oxidative stress in the blood. Administration of lipoic acid (LA), a probiotic with standard-fat diet (SFD, 10% fat) and low-fat diet (LFD, 5% fat) significantly decreased the concentration of 4-HNE as compared to the OVA (ovalbumin) + HFD group (p < 0.05). Treatment with low-fat diet or LFD in combination with apocynin insignificantly decreased H₂O₂ values as compared to the OVA + HFD group. Supplementation of probiotic with SFD and LFD significantly decreased the concentration of TBARS as compared to the OVA + SFD and saline + HDF groups (p < 0.05). Significantly lower concentrations of TBARS were also observed in the LA plus LFD group (p < 0.05) as compared to the OVA + HFD group. Low-fat diet with probiotic significantly increased the concentration of FRAP as compared to the obese mice (p = 0.017). Treatment with LFD in combination with LA significantly increased FRAP values as compared to the obese and obese asthmatic mice (p < 0.001).

Rhamnetin alleviates polystyrene microplastics-induced testicular damage by restoring biochemical, steroidogenic, hormonal, apoptotic, inflammatory, spermatogenic and histological profile in male albino rats

The current research was performed to evaluate the ameliorative effects of Rhamnetin (RHM) on polystyrene microplastics (PS-MPs)-instigated testicular dysfunction in male albino rats. 48 albino rats were distributed in four groups, i.e., control, PS-MPs treated, PS-MPs + RHM co-treated and RHM only supplemented group. PS-MPs exposure considerably reduced anti-oxidant enzymes i.e., catalase (CAT), glutathione peroxidase (GSR), superoxide dismutase (SOD) and glutathione reductase (GPx) activities. Whereas, reactive oxygen species (ROS) level along with malondialdehyde (MDA) was considerably escalated in PS-MPs treated rats as well as a potential decline was observed in sperm progressive motility. Additionally, a substantial upsurge was noticed in the count of dead sperms, deformity in the tail, mid-piece and head of sperms in PS-MPs treated rats. PS-MPs exposure also decreased steroidogenic enzymes, 17β-hydroxysteroid dehydrogenase (17β-HSD), steroidogenic acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) expressions. Moreover, the levels of inflammatory indices i.e., Interleukin-6 (IL-6), Nuclear factor kappa-B (NF-κB), Interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) activity were also increased in PS-MPs administrated group. Besides it increased the expression of apoptotic markers (Bax and caspase-3) expression. Whereas, anti-apoptotic marker i.e., Bcl-2 expression was reduced. Moreover, luteinizing hormone (LH), follicle-stimulating hormone (FSH) as well as plasma testosterone levels were also decreased. PS-MPs exposure also led to a substantial histopathological damage in testicular tissues. However, RHM supplementation potentially reduced the damaging effects of PS-MPs in the reproductive tissues of male albino rats. Thus, the current study revealed, RHM possesses potential to prevent PS-MPs-induced testicular damage due to its anti-oxidant anti-apoptotic, anti-inflammatory as well as androgenic properties.

Molecular regulation, breed differences and genes involved in stress control in farm animals

Stress is a state of disturbed homeostasis evoking a multiplicity of somatic and mental adaptive reactions resulting from any of the 5 freedoms of animals being violated. Many environmental forces disrupt homeostasis in farm animals, such as extreme temperatures, poor nutrition, noise, hunger, and thirst. During stressful situations, neuronal circuits in the limbic system and prefrontal cortex are activated, which lead to the release of adrenalin and noradrenalin. The hormones released during stress are needed for adaptation to acute stress and are regulated by many genes. This review examined molecular regulation, breed differences, and genes involved in stress control in farm animals. Major molecular regulation of stress, such as oxidative, cytosolic heat shock, unfolded protein, and hypoxic responses, were discussed. The responses of various poultry, ruminant, and pig breeds to different stress types were also discussed. Gene expressions and polymorphisms in the neuroendocrine and neurotransmitter pathways were also elucidated. The information obtained from this review will help farmers mitigate stress in farm animals through appropriate breed and gene-assisted selection. Also, information obtained from this review will add to the field of stress genetics since stress is a serious welfare issue in farm animals.

An oxygen-generating metal organic framework nanoplatform as a “synergy motor” for extricating dilemma over photodynamic therapy

Photodynamic therapy (PDT) combined with metal organic frameworks (MOFs) addresses current obstacles.

Synthesis and Antioxidant Evaluation of O-Methylated Emodacidamides: Starting from Parietin, a Secondary Metabolite of Lichen Xanthoria parietina

Polyhydroxy-anthraquinones bearing amino acids are found rather seldom in nature. Emodacidamides, isolated from a marine-derived fungus, Penicillium sp. SCSIO sof101 by Luo et al. (2017) are the first natural example of amino acid conjugated anthraquinone. In this study, O-methylated emodacidamides and emodinic acid-anilides were synthesized starting from parietin, extracted from the lichen Xanthoria parietina (L.) Th. Fr. The structural elucidations of prepared compounds were confirmed by 1D and 2D NMR analyses including HSQC and HMBC techniques. In addition, all newly synthesized compounds were evaluated for the antioxidant activities with free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging. The synthesized compounds showed low to moderate antioxidant and DPPH scavenging activities. The antioxidant activities were supported within quantum chemical calculations using the DFT-B3LYP/6-311++G(d,p) level of theory. It is observed that the antioxidant activity of emodacidamides mostly depends on the phenolic groups on anthraquinone ring. The phenolic groups on other substituents help to improve antioxidant activity and also the position of hydroxy group is a decisive factor for antioxidant ability.

Homeostasis of carbohydrates and reactive oxygen species is critically changed in the brain of middle-aged mice: molecular mechanisms and functional reasons

The brain is an organ that consumes a lot of energy. In the brain, energy is required for synaptic transmission, numerous biosynthetic processes and axonal transport in neurons, and for many supportive functions of glial cells. The main source of energy in the brain is glucose and to a lesser extent lactate and ketone bodies. ATP is formed at glucose catabolism via glycolysis and oxidative phosphorylation in mitochondrial electron transport chain (ETC) within mitochondria being the main source of ATP. With age, brain's energy metabolism is disturbed, involving a decrease in glycolysis and mitochondrial dysfunction. The latter is accompanied by intensified generation of reactive oxygen species (ROS) in ETC leading to oxidative stress. Recently, we have found that crucial changes in energy metabolism and intensity of oxidative stress in the mouse brain occur in middle age with minor progression in old age. In this review, we analyze the metabolic changes and functional causes that lead to these changes in the aging brain.

Exogenous methyl jasmonate induced cassava defense response and enhanced resistance to Tetranychus urticae

Exogenous application of methyl jasmonate (MeJA) could activate plant defense response against the two-spotted spider mite (TSSM), Tetranychus urticae Koch, in different plants. However, whether MeJA can also serve as an elicitor in cassava (Manihot esculenta Crantz) remains unknown. In this study, induced defense responses were investigated in TSSM-resistant cassava variety C1115 and TSSM-susceptible cassava variety KU50 when applied with MeJA. The performance of TSSM feeding on cassava plants that were pre-treated with various concentrations of MeJA was first evaluated. Subsequently, the activities of antioxidative enzymes (superoxide dismutase and catalase), detoxification enzymes (glutathione S-transferase, cytochrome P450 and carboxylesterase) and digestive enzymes (protease, amylase and invertase) in TSSM were analyzed at days 1, 2, 4 and 8 post-feeding. The results showed that MeJA treatment can induce cassava defense responses to TSSM in terms of reducing egg production and adult longevity as well as slowing development and prolonging the egg stage. Noticeably, C1115 exhibited stronger inhibition of TSSM development and reproduction than KU50. In addition, the activities of all the tested enzymes were induced in both C1115 and KU50, the most in C1115. We conclude that exogenous methyl jasmonate can induce cassava defense responses and enhance resistance to TSSM.

Single and combined effects of Zn and Al on photosystem II of the green microalgae Raphidocelis subcapitata assessed by pulse-amplitude modulated (PAM) fluorometry

Increasing metal concentrations in aquatic environments are mainly due to anthropogenic actions, which is a matter of concern for the biodiversity of aquatic biota. It is known that metals coexist in environments, however environmental risk assessments do not usually take into account the effects of these mixtures. We aimed to test Zn and Al mixtures on the photosynthetic apparatus of a green microalga, for the first time, using PAM fluorometry. After 72 h exposure, single concentrations from 0.08 to 0.46 µM Zn and 22.24 to 37.06 µM Al affected the photosynthetic parameters of Raphidocelis subcapitata. Metals affected the efficiency of the oxygen-evolving complex - OEC (F₀/F_v), increasing it by 25% at 0.46 µM Zn and by 82% at 37.06 µM Al - concentrations where, 57% and 78% of growth inhibition occurred, respectively. We observed that the algal growth was more sensitive to infer Zn toxicity, while F₀/F_v was more affected by Al. Regarding quenching, there was an increase in passive energy dissipation ((Y(NO)) at 0.46 µM Zn, and we observed an increase in both regulated ((NPQ and Y(NPQ)) and non-regulated energy dissipation ((qN and (Y(NO)) at 37.06 µM Al. Our results showed synergism and antagonism at different concentrations in mixtures, the antagonism prevailing at higher metal concentrations and, in some cases, synergism at lower concentrations of Zn and Al. Since we observe more than additive and less than additive effects, it is of the utmost importance to take mixture toxicity tests into account when performing risk assessments on green algae.

Comparative analysis of sulfiredoxin and total oxidative stress levels in diabetic individuals with periodontitis: A case-control study

BACKGROUND

The delicate balance between oxidative stress and its antioxidant system can be disrupted in diabetes mellitus (DM), making the tissue susceptible to injury. Hence, this case-control study aims to estimate and correlate the gingival tissue sulfiredoxin and crevicular total oxidative stress (TOS) levels in generalized periodontitis Stage II individuals Grade C (PSII) with and without type II DM.

MATERIAL AND METHODS

A total of 72 individuals were grouped based on their glycosylated hemoglobin (HbA1c) levels and clinical parameters: group I, periodontally healthy non-diabetic (HbA1c < 5.7%) (n = 24); group II, non-diabetic with PSII (n = 24); and group III, diabetic individuals (HbA1c > 6.5%) with PSII (n = 24). Gingival tissues and crevicular fluid samples were collected. The samples with adequate protein concentrations (n = 72) were further estimated for sulfiredoxin and TOS levels by enzyme-linked immunosorbent assay (ELISA) and calorimetric method, respectively.

RESULTS

Tissue sulfiredoxin and crevicular TOS levels are increased significantly in the periodontitis group compared to the non-periodontitis group (p < 0.001).The tissue sulfiredoxin levels did not vary significantly between the two periodontitis groups (p < 0.179). The TOS levels are significantly higher in the diabetic compared to non-diabetic periodontitis group (p < 0.001). Correlation statistics showed a significant positive correlation (r = 0.65 and p < 0.005) between sulfiredoxin and TOS levels in diabetes with PSII group, however, no such significant correlation was observed in the non-diabetic PSII group (r = 0.255 and p < 0.422).

CONCLUSION

Diabetic individuals showed inadequate sulfiredoxin-mediated antioxidant response to an increase in oxidative stress levels in periodontitis Stage II Grade C individuals.

Applications of Antioxidants in Dental Procedures

As people are paying more and more attention to dental health, various dental treatment procedures have emerged, such as tooth bleaching, dental implants, and dental restorations. However, a large number of free radicals are typically produced during the dental procedures. When the imbalance in distribution of reactive oxygen species (ROS) is induced, oxidative stress coupled with oxidative damage occurs. Oral inflammations such as those in periodontitis and pulpitis are also unavoidable. Therefore, the applications of exogenous antioxidants in oral environment have been proposed. In this article, the origin of ROS during dental procedures, the types of antioxidants, and their working mechanisms are reviewed. Additionally, antioxidants delivery in the complicated dental procedures and their feasibility for clinical applications are also covered. Finally, the importance of safety assessment of these materials and future work to take the challenge in antioxidants development are proposed for perspective.

Potential Cytoprotective and Regulatory Effects of Ergothioneine on Gene Expression of Proteins Involved in Erythroid Adaptation Mechanisms and Redox Pathways in K562 Cells

This study aimed to establish the importance of ergothioneine (ERT) in the erythroid adaptation mechanisms by appraising the expression levels of redox-related genes associated with the PI3K/AKT/FoxO3 and Nrf2-ARE pathways using K562 cells induced to erythroid differentiation and H₂O₂-oxidative stress. Cell viability and gene expression were evaluated. Two concentrations of ERT were assessed, 1 nM (C1) and 100 µM (C2), with and without stress induction (100 µM H₂O₂). Assessments were made in three periods of the cellular differentiation process (D0, D2, and D4). The C1 treatment promoted the induction of FOXO3 (D0 and 2), PSMB5, and 6 expressions (D4); C1 + H₂O₂ treatment showed the highest levels of NRF2 transcripts, KEAP1 (D0), YWHAQ (D2 and 4), PSMB5 (D2) and PSMB6 (D4); and C2 + H₂O₂ (D2) an increase in FOXO3 and MST1 expression, with a decrease of YWHAQ and NRF2 was observed. in C2 + H₂O₂ (D2) an increase in FOXO3 and MST1, with a decrease in YWHAQ and NRF2 was observed All ERT treatments increased gamma-globin expression. Statistical multivariate analyzes highlighted that the Nrf2-ARE pathway presented a greater contribution in the production of PRDX1, SOD1, CAT, and PSBM5 mRNAs, whereas the PI3K/AKT/FoxO3 pathway was associated with the PRDX2 and TRX transcripts. In conclusion, ERT presented a cytoprotective action through Nrf2 and FoxO3, with the latter seeming to contribute to erythroid proliferation/differentiation.

Role of macrophage scavenger receptor MSR1 in the progression of non-alcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease (NAFLD), and the dysregulation of lipid metabolism and oxidative stress are the typical features. Subsequent dyslipidemia and oxygen radical production may render the formation of modified lipids. Macrophage scavenger receptor 1 (MSR1) is responsible for the uptake of modified lipoprotein and is one of the key molecules in atherosclerosis. However, the unrestricted uptake of modified lipoproteins by MSR1 and the formation of cholesterol-rich foamy macrophages also can be observed in NASH patients and mouse models. In this review, we highlight the dysregulation of lipid metabolism and oxidative stress in NASH, the alteration of MSR1 expression in physiological and pathological conditions, the formation of modified lipoproteins, and the role of MSR1 on macrophage foaming and NASH development and progression.

Carob Seed Peels Effect on Cognitive Impairment and Oxidative Stress Status in Methionine-Induced Mice Models of Schizophrenia

Background:Ceratonia siliqua L. (Carob tree) is a Mediterranean evergreen, well known for its medicinal properties. The different parts of Carob were proven to exert antidiabetic, antibacterial, antifungal, and antiproliferative effects. Hence, the present paper aims to validate the positive correlation between the high antioxidant activity of carob seed peels and the improvement of negative symptoms of schizophrenia. Materials & Methods: The antioxidant activity was carried out using the β-carotene test. Methionine and carob seed peels (CSP) extracts (50 and 100 mg/kg) were orally administrated to mice for a week. After administration, behavioral tests were assessed using the Y-maze, elevated plus maze, and forced swimming tests, as well as the novel object recognition task. Furthermore, the oxidative stress status was evaluated by analyzing the levels of the antioxidant enzymes: Superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde levels (MDA). Results: Both extracts exhibited remarkable antioxidant activity and showed antibacterial effect against Gram-positive bacteria tested (Bacillus subtilis and Staphylococcus aureus) and against Pseudomonas aeruginosa (Gram-negative). Therefore, Escherichia coli was very resistant. The behavioral tests proved the efficacy of CSP in enhancing the cognitive impairment of animal models of schizophrenia. Hence, the stated correlation between oxidative stress and schizophrenia was confirmed by the increased SOD and GPx activities and the decreased MDA level. Conclusions: The present study gave further confirmation of the potential correlation between oxidative stress and the development of psychiatric disorders and highlighted the use of natural antioxidants, especially Ceratonia siliqua L. in the improvement of cognitive impairment in the dementia of schizophrenia.