Oxidative Burden Research Articles

Investigation of the chemical composition and biological activities of Eremurus spectabilis M. Bieb through antioxidant, enzyme inhibition, COX-2 and iNOS assessment.

Eremurus spectabilis is widespread and used primarily for medicinal and culinary purposes. This study aimed to evaluate the chemical composition, antiradical and antioxidant activities, enzyme inhibitory activities, and anti-inflammatory properties of various extracts from the aerial parts of E. spectabilis. Various assays were used to investigate the antioxidant and enzyme inhibitory properties. The chemical composition of the tested extracts was analyzed using High-Performance Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry (HPLC-ESI-MS/MS). Additionally, the extracts were tested on isolated mouse colon tissue challenged with E. coli lipopolysaccharide (LPS) to replicate the inflammation and oxidative stress burden characteristic of inflammatory bowel diseases. In the chemical composition, vanillic, ferulic, 4-hydroxybenzoic acids were the prominent compounds. The greatest antioxidant activity was observed in the methanol and water extracts from the aerial parts. Enzyme inhibition tests showed that the ethyl acetate extract had the highest anti-acetylcholinesterase activity. The gene expression of pro-inflammatory cyclooxygenase-2 (COX-2) and pro-oxidant inducible nitric oxide synthase (iNOS) biomarkers were assayed. Among the extracts, the methanol extract was the most effective in blunting LPS-induced gene expression of COX-2. E. spectabilis may serve as a valuable source of phytochemicals for combating oxidative stress and inflammation-driven diseases, with a particular emphasis on colon inflammatory condition.

Seasonal Changes in the Oxidative Potential of Urban Air Pollutants: The Influence of Emission Sources and Proton- and Ligand-Mediated Dissolution of Transition Metals.

The inhalation of fine particulate matter (PM2.5) is a major contributor to adverse health effects from air pollution worldwide. An important toxicity pathway is thought to follow oxidative stress from the formation of exogenous reactive oxygen species (ROS) in the body, a proxy of which is oxidative potential (OP). As redox-active transition metals and organic species are important drivers of OP in urban environments, we investigate how seasonal changes in emission sources, aerosol chemical composition, acidity, and metal dissolution influence OP dynamics. Using a kinetic model of the lung redox chemistry, we predicted ROS (O2 •-, H2O2, •OH) formation with input parameters comprising the ambient concentrations of PM2.5, water-soluble Fe and Cu, secondary organic matter, nitrogen dioxide, and ozone across two years and two urban sites in Canada. Particulate species were the largest contributors to ROS production. Soluble Fe and Cu had their highest and lowest values in summer and winter, and changes in Fe solubility were closely linked to seasonal variations in chemical aging, the acidity of aerosol, and organic ligand levels. The results indicate three conditions that influence OP across various seasons: (a) low aerosol pH and high organic ligand levels leading to the highest OP in summer, (b) opposite trends leading to the lowest OP in winter, and (c) intermediate conditions corresponding to moderate OP in spring and fall. This study highlights how atmospheric chemical aging modifies the oxidative burden of urban air pollutants, resulting in a seasonal cycle with a potential effect on population health.

Imperatorin ameliorates ferroptotic cell death, inflammation, and renal fibrosis in a unilateral ureteral obstruction mouse model

BackgroundImperatorin is a naturally occurring furocoumarin derivative found in traditional Chinese medicine Angelica dahurica for its anticancer, antihypertensive, and antidiabetic properties. Chronic kidney disease (CKD) is a global health issue, characterized by a high prevalence, significant morbidity and mortality, and a range of related complications. ObjectiveThis study aims to investigate the protective effects of imperatorin treatment and the specific underlying mechanisms in progressive CKD. MethodsImperatorin was orally administrated for 14 consecutive days to mice with unilateral ureteral obstruction (UUO) to investigate the renal pathological alternations, pro-inflammatory mediators, antioxidant response, and ferroptotic death signaling. Imperatorin was also tested in the erastin-induced injury of renal proximal tubular cells (NRK-52E). Cell viability, ferroptosis protein markers, erastin-induced oxidative stress, and lipid peroxidation were assessed. ResultsIn vivo, imperatorin treatment alleviated kidney histology alternations and attenuated the protein expression of fibrotic markers. Furthermore, imperatorin administration reduced inflammatory cell infiltration, and alleviated the oxidative stress burden by downregulating protein markers such as catalase, superoxide dismutase 2 (SOD-2), NADPH oxidase 4 (NOX-4), and thioredoxin reductase 1 (Trxr-1). It also mitigated ferroptosis markers such as glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11/cystine transporter (SLC7A11/xCT), and transferrin receptor 1 (TFR-1), and attenuated renal cell apoptosis. In vitro, imperatorin treatment effectively decreased erastin-induced feroptotic cell death, restored the antioxidant enzyme levels, and mitigated lipid peroxidation as well as the expression of ferroptosis-related markers (XCT, GPX4, and p-p53) in a dose-dependent manner. ConclusionOur finding demonstrated for the first time, that imperatorin treatment holds therapeutic potential in a UUO mouse model of CKD and inhibits the erastin-induced oxidative stress, ferroptosis, and subsequent lipid peroxidation in vitro. This highlights the potential of imperatorin as a future therapeutic target for ferroptosis to improve the progression of CKD.

Association between fasting lipid profile, inflammatory markers and oxidative stress markera burden of cardiovascular risk in postmenopausal women with high Body Mass Index

Cardiovascular diseases are becoming more successful in the entire population of individuals and is the leading cause of death in both men and women. The effect of cardiovascular disease is not appreciated high enough in women when set side by side in men. Women have eccentric variable determinants that increases the probability of cardiovascular diseases and postmenopausal women are at higher risk of developing cardiovascular diseases. Postmenopause is the time when menstrual period stops permanently in a women’s life. Several hormonal imbalances as well as metabolic changes make them more prone for cardiovascular diseases. Fasting lipid profile, inflammatory markers like hs-CRP, TNF-α, Adiponectin and oxidative stress marker like Malondialdehyde are found altered in high BMI postmenopausal women and this altered parameters tend to become a major CV risk. Aim and objective. The aim is to associate the levels of fasting lipid profile, inflammatory markers like hs-CRP, TNF-α, Adiponectin and oxidative stress marker like Malondialdehyde with cardiovascular disease in normal and high BMI postmenopausal women. Materials and methods. The research was directed on 104 postmenopausal women of age group 45–60 years and we grouped them into 2. Group 1 having normal BMI (18.50–24.99) and group 2 having high BMI > 25.00 based on Asian’s classification for BMI. Approval from the Institutional Ethical Committee was obtained before beginning the study. Postmenopausal women were instructed to report to physiology department at 7.30 am following overnight fasting and 5 ml of blood was collected to assess their fasting lipid profile, oxidative stress marker and inflammatory markers. Results & conclusion. Unpaired t-test was used to analyse all parameters of the study (control and study group). BMI, Total Cholesterol, Triacylglycerol, LDL-C, VLDL-C, hs-CRP, TNF-α, Malondialdehyde were significantly elevated and the levels of HDL-C and adiponectin were found reduced in high BMI postmenopausal women when compared to normal BMI postmenopausal women (p < 0.05) and all these factors are reported to be risk factors for adverse CV events.

Pirfenidone targeted mechanisms for alleviating methotrexate-induced testiculopathy in Wistar rats.

Testicular injury and affected spermatogenesis are major complications of methotrexate (MTX) use. Oxidative stress is one contributing process leading to inflammation and apoptosis induction. Pirfenidone (PFD) is a well-known anti-fibrotic drug prescribed for interstitial lung fibrosis, in addition to anti-inflammatory, antioxidative, and antiapoptotic capabilities. The study aimed to explore the potential protection afforded by PFD in a rat model of MTX-induced testiculopathy. The experimental design included four groups, each containing seven adult Wistar rats: control, PFD (500mg/kg/day, orally)-, MTX (0.5mg/kg, intraperitoneal, twice weekly)-, and PFD/MTX-treated groups. Treatment continued for 4weeks. Blood and testicular samples were harvested for biochemical, histological, immunohistochemical, and polymerase chain reaction (PCR) analyses. Also, the testicular damage and spermatogenic activity were graded by the testicular injury and Johnsen scoring system, respectively. PFD positively affected the serum testosterone (TST) level, reduced the testicular inflammatory mediators [tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β)], reduced the testicular oxidative burden, increased superoxide dismutase (SOD), and protected the testicular histological structure. In addition, antifibrotic effects, anti-caspase-3, and PCNA enhancement activity were recorded. PFD exhibited a protective potential and mitigated the MTX-induced testiculopathy via suppression of testicular oxidative stress, inflammation, fibrosis, and apoptosis and retaining the testicular proliferative efficacy as confirmed by histological, immunohistochemical, and biochemical methods.

Mitochondrial Dysfunction in Glycogen Storage Disorders (GSDs).

Glycogen storage disorders (GSDs) are a group of inherited metabolic disorders characterized by defects in enzymes involved in glycogen metabolism. Deficiencies in enzymes responsible for glycogen breakdown and synthesis can impair mitochondrial function. For instance, in GSD type II (Pompe disease), acid alpha-glucosidase deficiency leads to lysosomal glycogen accumulation, which secondarily impacts mitochondrial function through dysfunctional mitophagy, which disrupts mitochondrial quality control, generating oxidative stress. In GSD type III (Cori disease), the lack of the debranching enzyme causes glycogen accumulation and affects mitochondrial dynamics and biogenesis by disrupting the integrity of muscle fibers. Malfunctional glycogen metabolism can disrupt various cascades, thus causing mitochondrial and cell metabolic dysfunction through various mechanisms. These dysfunctions include altered mitochondrial morphology, impaired oxidative phosphorylation, increased production of reactive oxygen species (ROS), and defective mitophagy. The oxidative burden typical of GSDs compromises mitochondrial integrity and exacerbates the metabolic derangements observed in GSDs. The intertwining of mitochondrial dysfunction and GSDs underscores the complexity of these disorders and has significant clinical implications. GSD patients often present with multisystem manifestations, including hepatomegaly, hypoglycemia, and muscle weakness, which can be exacerbated by mitochondrial impairment. Moreover, mitochondrial dysfunction may contribute to the progression of GSD-related complications, such as cardiomyopathy and neurocognitive deficits. Targeting mitochondrial dysfunction thus represents a promising therapeutic avenue in GSDs. Potential strategies include antioxidants to mitigate oxidative stress, compounds that enhance mitochondrial biogenesis, and gene therapy to correct the underlying mitochondrial enzyme deficiencies. Mitochondrial dysfunction plays a critical role in the pathophysiology of GSDs. Recognizing and addressing this aspect can lead to more comprehensive and effective treatments, improving the quality of life of GSD patients. This review aims to elaborate on the intricate relationship between mitochondrial dysfunction and various types of GSDs. The review presents challenges and treatment options for several GSDs.

Knockdown of long non-coding RNA SBF2-AS1 inhibits calcium oxalate-induced HK-2 cell injury by regulating the miR-302e/NLRP3 pathway.

Long non-coding ribose nucleic acids (lncRNAs) have been implicated in the development of nephrolithiasis. The study aims to investigate the interplay of lncRNA SBF2-AS1 (SETbinding factor 2 antisense RNA 1) and NLR family pyrin domain containing 3 (NLRP3) in regulating the calcium oxalate monohydrate (COM)-induced human kidney HK-2 cell injury. HK-2 cells were treated with COM (100µg/mL) to create a cellular model of kidney injury. Gene and protein expression was assessed by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot. Proliferation and apoptosis rates, as well as levels of malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were measured. Additionally, potential miRNAs interacting with SBF2-AS1 and NLRP3 were predicted utilizing the starBase and TargetScan databases. The interference of SBF2-AS1 resulted in increased cell proliferation and SOD levels in HK-2 cells after COM induction. SBF2-AS1 silencing also reduced COM-induced cell death and inflammatory cytokine production by down-regulating NLRP3 protein expression. Conversely, forced upregulation of NLRP3 abrogated the effect of SBF2-AS1 interference. Notably, SBF2-AS1 interference on COM-induced oxidative stress and COM-induced cellular damage was rescued by antioxidant, indicating the involvement of oxidative burden in COM-induced damage. miR-302e acted as a mediator miRNA linking the functional association of SBF2-AS1 and NLRP3. Silencing SBF2-AS1 promoted miR-302e level and miR-302e reduced NLRP3 expression in HK-2 cells to protect against COM-induced damage. In summary, these findings suggest that downregulation of lncRNA SBF2-AS1 can potentially protect HK-2 cells from COM-induced injury by modulating the miR-302e/NLRP3 pathway.

Inducible RPE-specific GPX4 knockout causes oxidative stress and retinal degeneration with features of age-related macular degeneration

Age-related macular degeneration (AMD) is one of the leading causes of vision loss in the elderly. This disease involves oxidative stress burden in the retina leading to death of retinal pigment epithelial (RPE) cells and photoreceptors. The retina is susceptible to oxidative stress, in part due to high metabolic activity and high concentration of polyunsaturated fatty acids that undergo lipid peroxidation chain reactions. Antioxidant enzymes exist in the retina to combat this stress, including glutathione peroxidase 4 (GPX4). GPX4 specifically reduces oxidized lipids, protecting against lipid peroxidation-induced oxidative stress, which is noted in dry AMD. We hypothesize that Gpx4 knockout within the RPE will result in an environment of chronic oxidative stress yielding degeneration akin to AMD. C57BL/6J mice with a floxed Gpx4 gene were mated with Rpe65Cre/ER mice. Offspring containing Rpe65Cre ± alleles and either Gpx4 WT or Gpx4 fl/fl alleles were administered tamoxifen to induce Gpx4 knockout in Gpx4 fl/fl mice. At sequential timepoints, retinal phenotypes were assessed via in vivo imaging utilizing confocal scanning laser ophthalmoscopy and optical coherence tomography (OCT), and visual function was probed by electroretinography. Retinas were studied post-mortem by immunohistochemical analyses, electron microscopy, plastic sectioning, and quantitative polymerase chain reaction and Western analyses. The RPE-specific Gpx4 knockout model was validated via Western analysis indicating diminished GPX4 protein only within the RPE and not the neural retina. Following Gpx4 knockout, RPE cells became dysfunctional and died, with significant cell loss occurring 2 weeks post-knockout. Progressive thinning of the photoreceptor layer followed RPE degeneration and was accompanied by loss of visual function. OCT and light microscopy showed hyperreflective foci and enlarged, pigmented cells in and above the RPE layer. Electron microscopy revealed decreased mitochondrial cristae and loss of basal and apical RPE ultrastructure. Finally, there was increased carboxyethylpyrrole staining, indicating oxidation of docosahexaenoic acid, and increased levels of mRNAs encoding oxidative stress-associated genes in the RPE and photoreceptors. Overall, we show that RPE-localized GPX4 is necessary for the health of the RPE and outer retina, and that knockout recapitulates phenotypes of dry AMD.

Association between oxidative balance score and female infertility from the national health and nutrition examination survey 2013-2018.

The correlation between oxidative stress and female infertility pathogenesis was established, and the oxidative balance score (OBS) can serve as a measure of overall oxidative stress burden within an individual. Prior reports have not addressed the relationship between OBS and female infertility. This study endeavors to investigate the association between infertility risk in female and OBS. The analysis focused on data from the National Health and Nutrition Examination Survey 2013-2018. OBS was determined from 16 dietary components and 4 lifestyle components. Multivariate logistic regression was employed to investigate the relationship between OBS and female infertility. Further stratified analysis was conducted to examine the associations across various subgroups. To elucidate the dose-response relationship between infertility risk in female and OBS, a restricted cubic spline function was employed. The study included a total of 1410 participants. Through weighted multivariable logistic regression analysis, we observed a consistent inverse correlation between OBS and the risk of female infertility [OR (95% CI) = 0.97 (0.95, 0.99), p = 0.047]. When participants were segregated into quartiles based on OBS, those in the highest quartile had a 61% [OR (95% CI) = 0.39 (0.2, 0.79), p = 0.01] reduced risk of infertility compared to those in the lowest quartile of OBS. A trend test assessing OBS by quartile also revealed the relationship between OBS and female infertility. This correlation remained constant across both dietary and lifestyle OBS. Additionally, lifestyle OBS and female infertility exhibited a nonlinear association. A sensitivity analysis verified the consistency of our findings. The study found that a higher OBS is associated with a lower prevalence of female infertility. These results emphasized the potential role of oxidative homeostasis in the pathogenesis of infertility and highlighted the importance of follow-up studies and prevention strategies.

Free iron accumulation and oxidative stress burden induce ferroptotic atrophy of chicken yolk sac during the late embryogenesis

AbstractThe aim of this study was to investigate the mechanism of iron homeostasis and the ferroptosis pathway for yolk sac atrophy during late embryogenesis. To study the mechanism of yolk sac atrophy, 100 eggs were used. Further, 500 eggs were randomly divided into five treatments and in ovo feeding with different iron sources, such as FeSO4, ferrous glycinate (Fe‐Gly), or deferoxamine (DFO), to study the effects of free iron content on hatching quality and embryonic development. The results showed that total iron content of yolk decreased, but yolk sac increased from embryonic(E)13 to E19 (p < 0.05). Comparison of gene expression of iron transport systems showed that free iron accumulation and dysfunction occurred in the yolk sac. Yolk sac metabolites at E19 compared to E13 were more enriched in histidine and sulfur pathways, suppressing glutathione synthesis and resulting in oxidative stress damage in the yolk sac. Combined analysis of differential metabolites and gene expression in ferroptosis pathway at E13 and E19 revealed the activation of the yolk sac during late embryogenesis was probably through up‐regulation of ACSL4 expression and down‐regulation of GPX4 expression. Furthermore, in ovo feeding FeSO4 shortened the incubation time compared to CON, while Fe‐Gly or DFO delayed the hatching peak and increased hatching weight with less residual yolk. Collectively, it can be concluded that yolk sac atrophy during late embryogenesis may be mediated by iron disorders and provides a novel insight to modulate yolk sac nutrition, and hatching efficiency in chickens.

Pre-clinical Evidence-based Neuroprotective Potential of Naringin against Alzheimer's Disease-like Pathology: A Comprehensive Review.

Neurodegenerative disorders (NDs) are a group of progressive, chronic, and disabling disorders that are highly prevalent and the incidence is on a constant rise globally. Alzheimer's disease (AD), one of the most common neurodegenerative disorders is hallmarked by cognitive impairment, amyloid-β (Aβ) deposition, hyperphosphorylation of tau protein, cholinergic dysfunction, mitochondrial toxicity, and neurodegeneration. Available therapeutic agents only provide symptomatic relief and their use are limited due to serious side effects. Recent research has recognized flavonoids as potential multi-target biomolecules that can reduce the pathogenesis of AD. Naringin, a natural citrus flavonoid has been traditionally used to treat various NDs including AD, and has gained special attention because exhibits a neuroprotective effect by affecting numerous signaling pathways with minimum adverse effects. Naringin reduces deposition of Aβ, hyperphosphorylation of tau protein, cholinergic dysfunction, oxidative stress burden, mitochondrial toxicity, the activity of glutamate receptors, and apoptosis of the neuronal cells. Additionally, it reduces the expression of phosphorylated-P38/P38 and the NF-κB signaling pathway, showing that a wide range of molecular targets is involved in naringin's neuroprotective action. The present study describes the possible pharmacological targets, signaling pathways, and molecular mechanisms of naringin involved in neuroprotection against AD-like pathology. Based on the above pre-clinical reports it can be concluded that naringin could be an alternative therapeutic agent for the management of AD-like manifestation. Thus, there is a strong recommendation to perform more preclinical and clinical studies to develop naringin as a novel molecule that could be a multi-target drug to counteract AD.

Inside the genome: understanding genetic influences on oxidative stress.

Genetics is a key factor that governs the susceptibility to oxidative stress. In the body, oxidative burden is regulated by the balance between the prooxidant genes that orchestrate processes that produce oxidant species, while the antioxidant genes aid those involved in scavenging these species. Together, the two components aid in maintaining the oxidative balance in the body. Genetic variations can influence the expression and activity of the encoded proteins which can then affect their efficiency in regulating redox processes, thereby increasing the risk of oxidative stress. This review studies single nucleotide polymorphisms (SNPs) that bear relevance to oxidative stress by exploring the variations in the prooxidant genes, such as XDH, CYBA, CYP1A1, PTGS2, NOS, and MAO and antioxidant genes including SOD, CAT, GPX, GSS, GLUL, GSR, GSTM1, GSTM5, GSTP1, TXN and HMOX1. Early identification of individuals at the increased risk of oxidative stress is possible from the assessment of sequence of these genes. Integrating genetic insights into oxidative stress management measures can pave the way for personalized medicine that tailors' healthcare approaches to individual genetic profiles. Effective genetic assessment along with routine quantification of biological markers can improve and monitor treatment strategies, enhancing mitigation approaches that maintain cellular health and promote longevity.

Glycyrrhizin alleviates BoAHV-1-induced lung injury in guinea pigs by inhibiting the NF-κB/NLRP3 Signaling pathway and activating the Nrf2/HO-1 Signaling pathway.

Varicellovirus bovinealpha 1 (BoAHV-1) is a significant pathogen responsible for respiratory disease in cattle, capable of inducing lung damage independently or co-infection with bacteria. The widespread spread of BoAHV-1 in cattle herds has caused substantial economic losses to the cattle industry. The pathogenic mechanisms of BoAHV-1 are often relevant to robust inflammatory responses, increased oxidative burden, and the initiation of apoptosis. Glycyrrhizin (GLY) is a small-molecule triterpenoid saponin compound obtained from the herb liquorice, which has a broad spectrum of pharmacological properties such as antiviral, anti-inflammatory, and antioxidant effects. Furthermore, GLY regulates lung physiology by modulating oxidative stress, inflammatory response, and cell apoptosis through interference with the NF-κB/NLRP3 and Nrf2/HO-1 Signaling pathways. However, the potential of GLY to mitigate lung injury induced by BoAHV-1 and its underlying mechanism remains unclear. Therefore, in this study, we investigated the protective effect of GLY against pulmonary injury induced by BoAHV-1 in a guinea pig model by reducing viral load and suppressing the inflammatory response, oxidative stress, and apoptosis. The results of this study demonstrated that GLY exerted a protective effect against BoAHV-1-induced lung injury in guinea pigs. Specifically, GLY reduced the levels of pro-inflammatory cytokines interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and interleukin (IL)-8 in guinea pig tissues while suppressing the expression of Caspase-1. Additionally, GLY reduced BoAHV-1 load and the number of TUNEL-positive lung cells in guinea pig lungs while inhibiting Caspase 3 protein expression. Furthermore, GLY significantly enhanced lung antioxidant capacity by increasing superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity while simultaneously reducing malondialdehyde (MDA) levels. Lung histological observation and score further validated the protective effect of GLY on BoAHV-1-induced lung injury. Furthermore, we observed that the expression of phosphorylated NF-κB p65 (p-NF-κB p65) and NLRP3 proteins in the lung tissue of BoAHV-1-infected guinea pigs decreased after GLY treatment while the expression of Nrf2 and HO-1 proteins increased. These results indicated that GLY inhibited the NF-κB/NLRP3 Signaling pathway and activated the Nrf2/HO-1 Signaling pathway during BoAHV-1 infection. Ultimately, our findings demonstrated that GLY alleviates BoAHV-1-induced inflammation response, oxidative stress, and cell apoptosis by inhibiting the NF-κB/NLRP3 Signaling pathway and activating the Nrf2/HO-1 Signaling pathway to protect guinea pigs from lung injury caused by BoAHV-1. Ultimately, our findings demonstrated that GLY alleviates BoAHV-1-induced inflammation response, oxidative stress, and cell apoptosis by inhibiting the NF-κB/NLRP3 Signaling pathway and activating the Nrf2/HO-1 Signaling pathway to protect guinea pigs from lung injury caused by BoAHV-1. Importantly, this study provides a compelling argument for the GLY in combating respiratory disease in cattle caused by BoAHV-1.

Different organ distribution of nano- and micro-sized particulate matter results in different oxidative stress burden – implications for vascular function

Different organ distribution of nano- and micro-sized particulate matter results in different oxidative stress burden – implications for vascular function

Exploring the Therapeutic Effects of Radix Astragalus on Glioblastoma Multiforme Cell Culture

Objective: Glioblastomas, recognized for their aggressive and invasive nature, present a daunting challenge for effective treatment. At present, available therapies are not entirely efficacious in combating this primary brain tumor. In light of this, the present study aims to explore novel therapeutic strategies by investigating the antitumorigenic potential of Radix astragalus against Glioblastoma Multiforme (GBM) cell-lines in vitro. Methods: To accomplish this, the study employed a comprehensive research methodology that involved evaluating GBM cell viability and proliferation through MTT and LDH assays. Additionally, the study analyzed the oxidative burden of the GBM cell-line by measuring total antioxidant capacity (TAC), total oxidant status (TOS) and malondialdehyde (MDA) values, in order to further investigate the effects of Radix astragalus extracts. These advanced techniques allowed us to gain an in-depth understanding of the intricate molecular interactions between GBM cells and the extracts, paving the way for the development of novel therapies that can effectively combat this highly malignant disease. Results: The findings of this study demonstrate the remarkable antitumorigenic activity of Radix astragalus, as it significantly reduced cell viability in the GBM cell-line. Moreover, the extract inhibited the oxidative stress of GBM cells, which is a crucial factor that contributes to the development and progression of GBMs. Furthermore, the antioxidant assays revealed increased antioxidant activity in Radix astragalus-treated GBM cells compared to normal GBM cells. These findings offer a promising solution for treating GBMs, which are notoriously challenging to treat. Conclusion: The remarkable antitumorigenic activity of Radix astragalus identified in this study presents a novel avenue for cancer treatment research, with potential applications in the development of efficacious treatments against malignant brain tumors. Further exploration of the potential of Radix astragalus is warranted to pave the way for innovative therapies that can effectively combat GBMs.

Elevated Glucose Levels Increase Oxidative Stress in Human Cerebral Microvascular Endothelial Cells

Although glucose is the primary fuel source for cerebral metabolism and function, chronic exposure to high glucose levels impairs cerebral endothelial cell function and increases the risk of cerebrovascular accidents (CVA). Indeed, hyperglycemia is linked to an increased risk and prevalence of ischemic stroke, primarily attributed to the detrimental impact of glucose on cerebral endothelial cell function. The direct and indirect effects of glucose on brain endothelial cells are complex and not well understood. It is known that hyperglycemia can induce a profound pro-oxidative state with deleterious effects on peripheral vascular function resulting in pathologic outcome. The experimental aim of this study was to determine, in vitro, the effect of elevated glucose concentrations on cerebral endothelial cell oxidative stress. Human cerebral microvascular endothelial cells (hCMECs) were cultured (3rd passage) and incubated with culture media containing 5 mM D-glucose (normal glucose condition [NG]), 6.5 mM glucose (concentration representative of impaired fasting glucose [IFG]), and 8 mM (concentration representative of type 2 diabetes [T2D]) for 3 hours. Cells were harvested and intracellular reactive oxygen species (ROS) production was determined using CellROX Deep Red Reagent and expression of key anti-oxidant defense proteins, superoxide dismutase 1 (SOD-1) and catalase, were determined by capillary electrophoresis immunoassay. In separate experiments, the effect of each glucose condition was determined in the presence of the ROS scavenger, vitamin C (200 μmol). Cells treated with glucose concentration representing IFG (137+8 %) and T2D (162+12%) significantly increased intracellular ROS compared with NG (98+3 %). Concordantly, expression of SOD-1 and catalase were significantly higher in hCMECs treated with glucose concentration representing IFG (190.2+17.8 AU; 134.7+15.4 AU, respectively) and T2D (186.7+19.6 AU; 137.2+17.5 AU, respectively) compared with NG (24.4+1.8 AU; 65.6+4.3 AU, respectively). Pretreatment of cells with vitamin C prevented the increase in ROS in both the IFG and T2D conditions. Of note, there were no significant differences in ROS or the expression of SOD-1 and catalase in hCMECs between the IFG and T2D glucose conditions. In conclusion, glucose concentrations associated with IFG and T2D markedly increased ROS in hCMECs. In addition, there was a compensatory increase in SOD-1 and catalase to counteract the increase in cellular oxidative burden. Similar effects between the IFG and T2D glucose conditions on the oxidative milieu of hCMECs is consistent with the similar clinical cerebrovascular risk burden between these pathologic conditions. Glucose-induced increased oxidative stress in cerebral endothelial cells may contribute to the increased risk of CVA, such as ischemic stroke, associated with IFG and T2D. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Perinatal bisphenol S exposure exacerbates the oxidative burden and apoptosis in neonatal ovaries by suppressing the mTOR/autophagy axis

Bisphenol S (BPS) is an emerging environmental endocrine disruptor capable of crossing the placental barrier, resulting in widespread exposure to pregnant women due to its extensive usage. However, the impact of perinatal maternal exposure to BPS on reproductive health in offspring and the underlying molecular mechanism remain underexplored. In this study, gestational ICR mice were provided with drinking water containing 3.33 mg/L BPS to mimic possible human exposure in some countries. Results demonstrated that BPS accelerated the breakdown of germ-cell cysts and the assembly of primordial follicles in neonates, leading to oocyte over-loss. Furthermore, the expression levels of folliculogenesis-related genes (Kit, Nobox, Gdf9, Sohlh2, Kitl, Bmp15, Lhx8, Figla, and Tgfb1) decreased, thus compromising oocyte quality and disrupting early folliculogenesis dynamics. BPS also disrupted other aspects of offspring reproduction, including advancing puberty onset, disrupting the estrus cycle, and impairing fertility. Further investigation found that BPS exposure inhibited the activities and expression levels of antioxidant-related enzymes in neonatal ovaries, leading to the substantial accumulation of MDA and ROS. The increased oxidative burden exacerbated the intracellular apoptotic signaling, manifested by increased expression levels of pro-apoptotic markers (Bax, Caspase 3, and Caspase 9) and decreased expression levels of anti-apoptotic marker (Bcl2). Concurrently, BPS inhibited autophagy by increasing p-mTOR/mTOR and decreasing p-ULK1/ULK1, subsequently down-regulating autophagy flux-related biomarkers (LC3b/LC3a and Beclin-1) and impeding the degradation of autophagy substrate p62. However, the imbalanced crosstalk between autophagy, apoptosis and oxidative stress homeostasis was restored after rapamycin treatment. Collectively, the findings demonstrated that BPS exposure induced reproductive disorders in offspring by perturbing the mTOR/autophagy axis, and such autophagic dysfunction exacerbated redox imbalance and promoted excessive apoptosis. These results provide novel mechanistic insights into the role of autophagy in mitigating BPS-induced intergenerational reproductive dysfunction.

Ginsenoside Re protects against kainate-induced neurotoxicity in mice by attenuating mitochondrial dysfunction through activation of the signal transducers and activators of transcription 3 signaling

It was demonstrated that ginsenosides exert anti-convulsive potentials and interleukin-6 (IL-6) is protective from excitotoxicity induced by kainate (KA), a model of temporal lobe epilepsy. Ginsenosides-mediated mitochondrial recovery is essential for attenuating KA-induced neurotoxicity, however, little is known about the effects of ginsenoside Re (GRe), one of the major ginsenosides. In this study, GRe significantly attenuated KA-induced seizures in mice. KA-induced redox changes were more evident in mitochondrial fraction than in cytosolic fraction in the hippocampus of mice. GRe significantly attenuated KA-induced mitochondrial oxidative stress (i.e. increases in reactive oxygen species, 4-hydroxynonenal, and protein carbonyl) and mitochondrial dysfunction (i.e. the increase in intra-mitochondrial Ca2+ and the decrease in mitochondrial membrane potential). GRe or mitochondrial protectant cyclosporin A restored phospho-signal transducers and activators of transcription 3 (STAT3) and IL-6 levels reduced by KA, and the effects of GRe were reversed by the JAK2 inhibitor AG490 and the mitochondrial toxin 3-nitropropionic acid (3-NP). Thus, we used IL-6 knockout (KO) mice to investigate whether the interaction between STAT3 and IL-6 is involved in the GRe effects. Importantly, KA-induced reduction of manganese superoxide dismutase (SOD-2) levels and neurodegeneration (i.e. astroglial inhibition, microglial activation, and neuronal loss) were more prominent in IL-6 KO than in wild-type (WT) mice. These KA-induced detrimental effects were attenuated by GRe in WT and, unexpectedly, IL-6 KO mice, which were counteracted by AG490 and 3-NP. Our results suggest that GRe attenuates KA-induced neurodegeneration via modulating mitochondrial oxidative burden, mitochondrial dysfunction, and STAT3 signaling in mice.

Abstract 199: Fluid shear stress enhances metastatic potential and rapidly alters metabolism of circulating tumor cells

Abstract Background and Purpose: Circulating tumor cells (CTCs) are exposed to mechanical and biochemical stresses including fluid shear stress (FSS) and oxidative distress. Recently we have shown that viable CTCs actively resist destruction when exposed to FSS by a mechano-adaptive mechanism that depends on RhoA-actomyosin activity [PMID: 32187555]. Since the RhoA-actomyosin axis is implicated in other cellular behaviors that might contribute to metastasis; herein, we explored the hypothesis that exposure to FSS alters the biology of viable CTCs to promote metastatic colonization. Methodology: To determine if exposure to FSS alters metastatic potential, we exposed PC-3 prostate and MDA-MB-231 breast cancer cells to FSS prior to injection into the tail-vein of NCG mice. We then monitored metastatic colonization by weekly bioluminescence imaging. Further, we examined if FSS exposure altered the invasive potential of PC-3 and MDA-MB-231 cells, as well as their ability to survive/proliferate under anchorage-independent conditions. We conducted GC/LC-MS metabolomic profiling and measured lactate production following FSS exposure. To investigate oxidative burden on FSS exposed cells, we used dihydroethidium to measure general ROS production and a lipid peroxide sensor. Results: We found that FSS exposure shortens the time for metastatic colonization for both cell lines. We found that FSS exposure leads to approximately two-fold increase in invasion through collagen matrix, which, for PC-3 cells, is RhoA dependent. Moreover, FSS exposure resulted in increased proliferation (~25%) under anchorage independent conditions in both cell lines. Metabolomic profiling revealed that FSS exposure resulted increased glycolysis, reduced entry into the TCA cycle, and increased lactate levels. We blocked glycolysis in PC-3 and MDA-MB-231 cells with 2-deoxyglucose and found that this increased the fraction of cells destroyed by FSS ~20-30%. We also investigated redox stress and found that compared to cells held in suspension, those exposed to FSS demonstrate lower ROS burden. Interestingly, cells exposed to FSS exhibit lower levels of lipid peroxides in a manner that depends on RhoA. Conclusion: Our findings demonstrate that brief pulses of FSS exposure can enhance metastatic potential, increase invasive and anchorage-independent proliferative capacity and rapidly alter metabolism. The phenotypic changes driven by exposure to FSS depend in part on RhoA activation but may also reflect other mechanisms by which cancer cells sense and respond to FSS. The rapid changes in metabolism may act to reduce oxidative distress while CTCs are in suspension. In summary, our data indicate that FSS exposure in the circulation not only represents a physical force that CTCs must overcome to survive, but it also provides instructive cues that may enhance the metastatic behavior of some CTCs. Citation Format: Devon L. Moose, Amanda N. Pope, Marion Dykstra, Eric B. Taylor, Patrick Breheny, Michael D. Henry. Fluid shear stress enhances metastatic potential and rapidly alters metabolism of circulating tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 199.

Neuro-modulatory impact of felodipine against experimentally-induced Parkinson's disease: Possible contribution of PINK1-Parkin mitophagy pathway

Parkinson's disease (PD) is a prevalent neurodegenerative disorder, characterized by motor and psychological dysfunction. Palliative treatment and dopamine replenishment therapy are the only available therapeutic options. Calcium channel blockers (CCBs) have been reported to protect against several neurodegenerative disorders. The current study was designed to evaluate the neuroprotective impact of Felodipine (10 mg/kg, orally) as a CCB on motor and biochemical dysfunction associated with experimentally induced PD using rotenone (2.5 mg/kg, IP) and to investigate the underlying mechanisms. Rotenone induced deleterious neuromotor outcomes, typical of those associated with PD. The striatum revealed increased oxidative burden and NO levels with decreased antioxidant capacity. Nrf2 content significantly decreased with the accumulation of α-synuclein and tau proteins in both the substantia nigra and striatum. These observations significantly improved with felodipine treatment. Of note, felodipine increased dopamine levels in the substantia nigra and striatum as confirmed by the suppression of inflammation and the significant reduction in striatal NF-κB and TNF-α contents. Moreover, felodipine enhanced mitophagy, as confirmed by a significant increase in mitochondrial Parkin and suppression of LC3a/b and SQSTM1/p62. In conclusion, felodipine restored dopamine synthesis, attenuated oxidative stress, inflammation, and mitochondrial dysfunction, and improved the mitophagy process resulting in improved PD-associated motor impairment.