Inhibition Of Reactive Oxygen Species Formation Research Articles

Anti-inflammatory effect and its mechanism of Saracae Cortex based on zebrafish model and network pharmacology

This paper aims to explore the anti-inflammatory mechanism of Saracae Cortex by using network pharmacology and molecular docking methods and verify it through the inflammation model of zebrafish. The effective components, potential core targets, and signaling pathways of Saracae Cortex were obtained by using network pharmacology. A lipopolysaccharide(LPS)-induced inflammation model of zebrafish was established to evaluate the anti-inflammatory activity of aqueous extract and 70% ethanol extract of Saracae Cortex with cell apoptosis rate and reactive oxygen species(ROS) production rate as indicators. q PCR was performed to verify the main targets predicted by network pharmacology. The prediction found that there were 121 potential anti-inflammatory targets in Saracae Cortex. Protein-protein interaction(PPI) analysis showed that Saracae Cortex mainly acted on signal transducer and activator of transcription 3(STAT3), vascular endothelial growth factor A( VEGFA), epidermal growth factor( EGF), tumor necrosis factor( TNF),tumor protein p53(TP53), matrix metalloprotein 9(MMP9), c-fos proto-oncogene protein(FOS), estrogen receptor 1(ESR1), cx-c motif chemokine ligand 8(CXCL8), cluster of differentiation 8(CD8), and other targets. Gene Ontology(GO) analysis showed the biological process mainly acted on the inhibition of apoptosis, the positive regulation of gene expression, and the positive regulation of cell proliferation. Kyoto Encyclopedia of Genes and Genomes(KEGG) analysis showed that the mitogen-activated protein kinase(MAPK) signaling pathway, PI3K-Akt signaling pathway, and hypoxia-inducible factor 1(HIF-1) signaling pathway may play a key role in anti-inflammation of Saracae Cortex. Molecular docking verified that five key compounds had a strong binding force with their corresponding core target. Zebrafish animal experiments showed that Saracae Cortex could significantly inhibit ROS formation and reduce cell apoptosis in juvenile fish caused by inflammation and inhibit the further enhancement of inflammatory response in tissue. In addition, compared with the blank group, the transcription levels of nuclear factor kappa-B(NF-κB), TP53, FOS, adaptor protein complex-1(AP-1), and mitogen-activated protein kinases P38(P38) were significantly up-regulated in the model group. Compared with the model group, the m RNA expression of NF-κB, TP53, FOS, AP-1, and P38 was significantly down-regulated in zebrafish tissue treated with aqueous extract and 70% ethanol extract of Saracae Cortex. Saracae Cortex plays an anti-inflammatory role through multiple components and targets, and its anti-inflammatory effect may be related to the inhibition of the MAPK signaling pathway.

A role for sirtuin 1 in FGF23 activation following β-glycerophosphate treatment

Phosphate homeostasis is vital for many biological processes and disruptions in circulating levels can be detrimental. While the mechanisms behind FGF23 regulation have been regularly studied, the role of extracellular phosphate sensing and its impact on fibroblast growth factor 23 (FGF23) expression remains unclear. This study aimed to investigate the involvement of reactive oxygen species (ROS), silent information regulator 1 (SIRT1), and Hairy and Enhancer of Split-1 (HES1) in regulating FGF23 in FGF23 expressing MC3T3-E1 cells. MC3T3-E1 cells treated with β-glycerophosphate (BGP) resulted in increased Fgf23 expression. Inhibition of ROS formation by inhibition of NADPH oxidase, which is essential for ROS production, did not affect this response to BGP, suggesting ROS is not involved in this process. Moreover, treatment with tert-butyl hydroperoxide (TBHP), a ROS-inducing agent, did not increase Fgf23 expression. This suggests that ROS machinery is not involved in FGF23 stimulation as previously suggested. Nonetheless, inhibition of SIRT1 using Ex527 eliminated the Fgf23 response to BGP, indicating its involvement in FGF23 regulation after BGP treatment. Indeed, activation of SIRT1 using SRT1720 increased Fgf23 expression. Moreover, transcription factor Hes1 was upregulated by BGP treatment, which was diminished when cells were treated with Ex527 implying it is also regulated through SIRT1. These findings suggest the existence of an upstream SIRT1-HES1 axis in the regulation of FGF23 by phosphate, though we were unable to find a role for ROS in this process. Further research should provide insights into phosphate homeostasis and potential therapeutic targets for phosphate-related disorders.

Weak magnetic fields modulate superoxide to control planarian regeneration

Reactive oxygen species (ROS) signaling regulates cell behaviors and tissue growth in development, regeneration, and cancer. Commonly, ROS are modulated pharmacologically, which while effective comes with potential complications such as off-target effects and lack of drug tolerance. Thus, additional non-invasive therapeutic methods are necessary. Recent advances have highlighted the use of weak magnetic fields (WMFs, <1 mT) as one promising approach. We previously showed that 200 μT WMFs inhibit ROS formation and block planarian regeneration. However, WMF research in different model systems at various field strengths have produced a range of results that do not fit common dose response curves, making it unclear if WMF effects are predictable. Here, we test hypotheses based on spin state theory and the radical pair mechanism, which outlines how magnetic fields can alter the formation of radical pairs by changing electron spin states. This mechanism suggests that across a broad range of field strengths (0–900 μT) some WMF exposures should be able to inhibit while others promote ROS formation in a binary fashion. Our data reveal that WMFs can be used for directed manipulation of stem cell proliferation, differentiation, and tissue growth in predictable ways for both loss and gain of function during regenerative growth. Furthermore, we examine two of the most common ROS signaling effectors, hydrogen peroxide and superoxide, to begin the identification and elucidation of the specific molecular targets by which WMFs affect tissue growth. Together, our data reveal that the cellular effects of WMF exposure are highly dependent on ROS, and we identify superoxide as a specific ROS being modulated. Altogether, these data highlight the possibilities of using WMF exposures to control ROS signaling in vivo and represent an exciting new area of research.

Potential Anti-Inflammatory and Chondroprotective Effect of Luzula sylvatica.

(1) Interest in the Juncaceae family has risen as some members have shown anti-inflammatory properties and interesting compounds. In this regard, we decided to investigate the antioxidant and anti-inflammatory properties of Luzula sylvatica, a Juncaceae not yet extensively studied, in the context of osteoarthritis. (2) The Luzula sylvatica Ethanol extract (LS-E) was used to test the production of reactive oxygen species (ROS) by leucocytes, the IL1β and PGE2 production by peripheral blood mononuclear cells (PBMCs), the production of EP4, and the activation of NFκB in THP-1, as well as the IL1β-activated normal human knee articular chondrocytes (NHAC-Kn) gene expression, grown in monolayers or maintained in alginate beads. (3) Organic acids, caffeoylquinic acids, quercetin and luteolin, compounds frequently found in this family were identified. The LS-E exhibited inhibited ROS formation. The LS-E did not affect NFκB activation and IL1β secretion but dampened the secretion of PGE2 by PBMCs and the presence of EP4 in THP-1. It also modulated the expression of NHAC-Kn in both models and inhibited the expression of several proteases and inflammatory mediators. (4) Luzula sylvatica might supply interesting antioxidant protection against cartilage damages and lessen joint inflammation, notably by decreasing PGE2 secretion in the synovial fluid. Moreover, it could act directly on chondrocytes by decreasing the expression of proteases and, thus, preventing the degradation of the extracellular matrix.

Circulating Permeability Factors in Focal Segmental Glomerulosclerosis: In Vitro Detection

The recurrence of proteinuria after kidney transplantation in patients with focal segmental glomerulosclerosis (FSGS) is considered proof of the presence of circulating permeability factors (CPFs). The aim of this study is to demonstrate the presence of plasma CPFs using series of invitro assays. Podocytes and endothelial cells (glomerular microvascular endothelial cells [GMVECs]) were incubated with plasma from FSGS patients with presumed CPFs in relapse and remission and from steroid-resistant nephrotic syndrome (SRNS), steroid-sensitive nephrotic syndrome (SSNS), membranous nephropathy (MN), and healthy controls (hCtrls). Cell viability, podocyte actin cytoskeleton architecture, and reactive oxygen species (ROS) formation with or without ROS scavenger were investigated by Cell Counting Kit-8 assay, immunofluorescence staining, and CM-H2DCFDA probing, respectively. Presumed CPF-containing plasma causes a series of events in podocytes but not in GMVECs. These events include actin cytoskeleton rearrangement and excessive formation of ROS, which results in podocyte loss. These effects were solely observed in response to CPF plasma collected during relapse, but not in response to plasma of hCtrls, or patients with SRNS, SSNS, and MN. The copresence of dimethylthiourea, a scavenger of ROS, abolished the aforementioned effects of CPF plasma. We provide a panel of invitro bioassays to measure podocyte injury and predict the presence of CPFs in plasma of patients with nephrotic syndrome (NS), providing a new framework for monitoring CPF activity that may contribute to future NS diagnostics or used for disease monitoring purposes. Moreover, our findings suggest that the inhibition of ROS formation or facilitating rapid ROS scavenging may exert beneficial effects in patients with CPFs.

Combined Activity of the Redox-Modulating Compound Setanaxib (GKT137831) with Cytotoxic Agents in the Killing of Acute Myeloid Leukemia Cells.

Acute myeloid leukemia (AML) cells harbor elevated levels of reactive oxygen species (ROS), which promote cell proliferation and cause oxidative stress. Therefore, the inhibition of ROS formation or elevation beyond a toxic level have been considered as therapeutic strategies. ROS elevation has recently been linked to enhanced NADPH oxidase 4 (NOX4) activity. Therefore, the compound Setanaxib (GKT137831), a clinically advanced ROS-modulating substance, which has initially been identified as a NOX1/4 inhibitor, was tested for its inhibitory activity on AML cells. Setanaxib showed antiproliferative activity as single compound, and strongly enhanced the cytotoxic action of anthracyclines such as daunorubicin in vitro. Setanaxib attenuated disease in a mouse model of FLT3-ITD driven myeloproliferation in vivo. Setanaxib did not significantly inhibit FLT3-ITD signaling, including FLT3 autophosphorylation, activation of STAT5, AKT, or extracellular signal regulated kinase 1 and 2 (ERK1/2). Surprisingly, the effects of Setanaxib on cell proliferation appeared to be independent of the presence of NOX4 and were not associated with ROS quenching. Instead, Setanaxib caused elevation of ROS levels in the AML cells and importantly, enhanced anthracycline-induced ROS formation, which may contribute to the combined effects. Further assessment of Setanaxib as potential enhancer of cytotoxic AML therapy appears warranted.

Diallyl Sulfide Attenuation of Carcinogenesis in Mammary Epithelial Cells through the Inhibition of ROS Formation, and DNA Strand Breaks.

Garlic has long been used medicinally for many diseases, including cancer. One of the active garlic components is diallyl sulfide (DAS), which prevents carcinogenesis and reduces the incidence rate of several cancers. In this study, non-cancerous MCF-10A cells were used as a model to investigate the effect of DAS on Benzo (a)pyrene (BaP)-induced cellular carcinogenesis. The cells were evaluated based on changes in proliferation, cell cycle arrest, the formation of peroxides, 8-hydroxy-2-deoxyguanosine (8-OHdG) levels, the generation of DNA strand breaks, and DNA Polymerase β (Pol β) expression. The results obtained indicate that when co-treated with BaP, DAS inhibited BaP-induced cell proliferation (p < 0.05) to levels similar to the negative control. BaP treatment results in a two-fold increase in the accumulation of cells in the G2/M-phase of the cell cycle, which is restored to baseline levels, similar to untreated cells and vehicle-treated cells, when pretreated with 6 μM and 60 μM DAS, respectively. Co-treatment with DAS (60 μM and 600 μM) inhibited BaP-induced reactive oxygen species (ROS) formation by 132% and 133%, respectively, as determined by the accumulation of H2O2 in the extracellular medium and an increase in 8-OHdG levels of treated cells. All DAS concentrations inhibited BaP-induced DNA strand breaks through co-treatment and pre-treatment methods at all time points evaluated. Co-Treatment with 60 μM DAS increased DNA Pol β expression in response to BaP-induced lipid peroxidation and oxidative DNA damage. These results indicate that DAS effectively inhibited BaP-induced cell proliferation, cell cycle transitions, ROS, and DNA damage in an MCF-10A cell line. These results provide more experimental evidence for garlic’s antitumor abilities and corroborate many epidemiological studies regarding the association between the increased intake of garlic and the reduced risk of several types of cancer.

Effect of Vitamin C on Reactive Oxygen Species Formation in Erythrocytes of Sickle Cell Anemia Patients

Background: Sickle cell patients produce more reactive oxygen species (ROS) than healthy individuals, leading to increased cell membrane damage. Theoretically, reducing ROS formation would preserve red cell membranes of sickle cell patients. Vitamin C is a powerful anti-oxidant capable of inhibiting ROS formation in a variety of situations, by functioning as an electron donor to reduce molecular oxygen. This study aimed to determine whether Vitamin C reduced ROS formation in sickle red cells.Methods: 27 homozygous (HbSS) patients were recruited from the outpatient clinics of Lagos University Teaching Hospital, Nigeria, and annex at the Sickle Cell Foundation, Lagos, Nigeria. Demographic information and EDTA patient blood samples were collected. The test group were red cells preincubated in 80uM and 100uM Vitamin C concentrations before stressing with tertbutylhydroperoxide. These were compared to stressed matched controls preincubated in phosphate buffered saline. Cell staining was done with CellRox Orange followed by flow cytometry to quantify ROS.Results: ROS count for Vitamin C pre-treated red cells was significantly lower than matched controls (p<0.001). Average ROS count for 80uM test samples was 27.5/ul (95% CI, 17.5 to 72.5) and for 100uM 3.9/ul (95% CI, 1.9 to 5.9). Male gender was significantly associated with elevated baseline ROS count (p=0.03).Conclusion: Vitamin C reduced ROS formation in HbSS cells. Future studies should focus on a role for Vitamin C as a safe, cheap addition to maintenance therapy of sickle cell patients. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Intratesticular Human Adipose-Derived Stem Cell (hADSC) Transplantation Decreased Oxidative Stress in Testicular Torsion Model of Wistar Rat

IntroductionTesticular torsion is a sudden rotation of the testis towards its axis, which causes the twisting of the spermatic cord. Post-detorsion reperfusion will cause inflammation and trigger oxidative stress, which generates reactive oxygen species (ROS). Malondialdehyde (MDA) is an organic compound formed from ROS frequently used as an oxidative stress biomarker during ischemia and ischemia-reperfusion injury. In some organs, stem cell administration on the damaged organ is essential in preventing cellular damage and death. This study aimed to learn about the effect of hADSC administration on an ischemia-reperfusion injury.Material and MethodsA total of 22 Wistar rats divided into 5 groups, two groups each consist of 5 male Wistar rats with testicular torsion model without hADSC therapy (group I), while 2 other groups consist of 5 rats with testicular torsion model were given 1.0×106 cells intratesticular hADSC injection 30 minutes after testicular detorsion (group II). Both groups were euthanized at 1 and 4 weeks of observation. The last group consists of 2 rats without any treatment or model (negative control group). Following euthanasia, testicular tissue was harvested for MDA expression measurement using ELISA and histopathological examination. Statistical analysis using an one way ANOVA was done with SPSS version 21.0.ResultsThe result of MDA examination using the ELISA method has shown a concentration difference between group I (control) and group II (hADSC treatment). Testicular MDA concentration in the treatment group was significantly lower on the 1st and 4th week of observation (p2=0.000, p4=0.016). Post hoc analysis showed no statistically different between therapy and healthy group (p=0.972). On histopathological examination, Johnsen score in the treatment group was significantly higher on the 4th week of observation (p=0.044). Post hoc analysis showed no statistically different between therapy and healthy group (p=0.195).ConclusionIntratesticular hADSC administration can inhibit ROS formation due to ischemia-reperfusion injury in testicular tissue after testicular detorsion in Wistar rats.

Ellagic acid alleviates clozapine‑induced oxidative stress and mitochondrial dysfunction in cardiomyocytes

Clozapine (CLZ) as an antipsychotic agent is very effective in treating of psychosis disorders and resistant schizophrenia, but the risk of severe cardiac toxicity effects restricts its clinical use. There are several interrelated hypotheses to explain clozapine-induced cardiotoxicity which all of them may be related to oxidative stress. Therefore, the current study investigated the harmful effects of clozapine on cardiomyocytes and assessed the cytoprotective effect of ellagic acid (EA). Freshly isolated adult rat ventricular cardiomyocytes were incubated for 4 h at 37 °C with 00.05% ethanol as control, CLZ (50 µM), CLZ (50 µM) + a series of EA concentrations (10, 20 and 50 µM) and EA (50 µM). To evaluate the protective effect of EA, the markers of cell viability, reactive oxygen species (ROS) formation, mitochondria membrane potential (ΔΨm) collapse, lysosomal membrane integrity, malondialdehyde (MDA) and oxidized/reduced glutathione (GSH/GSSG) content were checked by biochemical and flowcytometry techniques. Our results demonstrated that EA (10, 20 and 50 µM) effectively inhibited CLZ-induced cytotoxicity which is associated with ROS overproduction and amelioration of mitochondrial and lysosomal damages. In addition, EA (10, 20 and 50 µM) in the presence of CLZ reduced the production of MDA as a specific marker lipid peroxidation and GSSG. Collectively, these findings suggested that EA protects cardiomyocytes from oxidative injury through inhibiting ROS formation, mitochondria dysfunction, and lysosomal damages, which suggest a potential therapeutic strategy of EA for CLZ-induced oxidative stress and cardiotoxicity.

Collagen and soy peptides attenuate contractile loss from UVA damage and enhance the antioxidant capacity of dermal fibroblasts.

Wrinkles and extracellular matrix (ECM) loss are common signs of skin aging and are thought to be the result of damage caused by reactive oxygen species (ROS); ROS induces an imbalance between ECM degradation and production. In this study, we evaluate soy peptides (SP) and collagen peptides (CP), alone and in combination, for their ability to inhibit ROS formation and increase ECM gene expression in order to ameliorate the signs of skin aging. Using tert-Butyl hydroperoxide (t-BuOOH)-treated dermal fibroblasts, we explored the potential of CP and SP to inhibit ROS formation by flow cytometry, as well as their effect on ECM component genes by real-time quantitative PCR. In addition, we examined the effect of CP and SP on UVA irradiated fibroblasts in a 3D collagen lattice model that measured contractility. The results showed that the combination of CP and SP synergistically reduces ROS formation. This combination also increased expression of collagen I, collagen II, elastin, and fibronectin in t-BuOOH-treated or untreated dermal fibroblasts. In the UVA-treated 3D collagen lattice model, the results show that CP and SP significantly improved fibroblast contractility when compared to UVA control (P<0.05). In conclusion, CP and SP attenuate the loss of contractility due to UVA damage, inhibit t-BuOOH-induced ROS formation, and improve expression of ECM component genes.

Protective effects of a comprehensive topical antioxidant against ozone-induced damage in a reconstructed human skin model

Tropospheric ozone (O3) is a source of oxidative stress. This study examined the ability of a topical antioxidant (WEL-DS) to inhibit O3-mediated damage in a human epidermal skin model. Four groups of tissues (N = 24) were compared: Group 1 (control) were untreated and unexposed; Group 2 were untreated and exposed to O3 (0.4 ppm, 4 h); Group 3 were pretreated with WEL-DS and unexposed; Group 4 were pretreated with WEL-DS and exposed to O3 (0.4 ppm, 4 h). Pretreated tissues were topically treated with 20 uL of WEL-DS and incubated for up to 20 h at 37 °C [humidified, 5% carbon dioxide (CO2)]. After 24 h, tissues were re-treated with WEL-DS and exposed to O3. Tissues were evaluated for Reactive Oxygen Species (ROS), hydrogen peroxide (H2O2), 4-hydroxynonenal (4-HNE) protein adducts, NF-κB p65 response and histology. In O3-exposed groups, WEL-DS significantly inhibited ROS formation vs. untreated tissues (p < 0.05). Pretreatment with WEL-DS inhibited H2O2 production vs. untreated tissues (p < 0.05), and decreased NF-κB p65 transcription factor signal. Oxidative stress induction in O3-exposed tissues was confirmed by increased levels of 4-HNE protein adducts (marker of lipid peroxidation); WEL-DS application reduced this effect. WEL-DS inhibited damage in tissues exposed to O3 with no significant changes in epidermal structure. A comprehensive topical antioxidant significantly diminished O3-induced oxidative damage in a human epidermal skin model.

Hydrogen attenuates radiation-induced intestinal damage by reducing oxidative stress and inflammatory response

The small intestine is known to be particularly sensitive to radiation, and the major limiting factor of radiotherapy is the gastrointestinal syndrome that subsequently develops after its administration. The detrimental effects of radiation are mostly mediated via the overproduction of reactive oxygen species (ROS), especially the hydroxyl radical (·OH). Because hydrogen is a selective ·OH scavenger, we hypothesized that hydrogen might exert a protective effect against radiation-induced intestinal damage. Herein, radiation models were built both in mice and in an intestinal crypt epithelial cell (IEC-6) line. In the animal experiment, we demonstrated that hydrogen-rich saline significantly reduced radiation-induced intestinal mucosal damage, improved intestinal function, and increased the survival rate. In addition, radiation-induced oxidative stress damage and systemic inflammatory response were also mitigated by hydrogen treatment. Moreover, hydrogen treatment decreased cell apoptosis and maintained intestinal epithelial cell proliferation in mice. In vitro experiments using the IEC-6 cell line showed that hydrogen-rich medium significantly inhibited ROS formation, maintained cell viability, and inhibited cell apoptosis. Importantly, hydrogen treatment prevented mitochondrial depolarization, cytochrome c release, and activity of caspase-3, caspase-9, and PARP. Moreover, the decreased expression of Bcl-xl and Bcl-2 and the increased expression of Bax protein were also blocked by hydrogen treatment. In conclusion, our study concurrently demonstrated that hydrogen provides an obviously protective effect on radiation-induced intestinal and cell injuries. Our work demonstrated that this protective effect might be due to the blockage of the mitochondrial apoptotic pathway.

Peroxiredoxin 4 attenuates glutamate-induced neuronal cell death through inhibition of endoplasmic reticulum stress

High concentrations of glutamate induce neurotoxicity by eliciting reactive oxygen species (ROS) generation and intracellular Ca2+ influx. The disruption of Ca2+ homeostasis in the endoplasmic reticulum (ER) evokes ER stress, ultimately resulting in neuronal dysfunction. Additionally, glutamate participates in the development of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. Peroxiredoxins (Prxs) are members of a family of antioxidant enzymes that protect cells from neurotoxic factor-induced apoptosis by scavenging hydrogen peroxide (H2O2). Prx4 is located in the ER and controls the redox condition within the ER. The present study investigated the protective effects of Prx4 against glutamate-induced neurotoxicity linked to ER stress. HT22 cells in which Prx4 was either overexpressed or silenced were used to elucidate the protective role of Prx4 against glutamate toxicity. The expression of Prx4 in HT22 cells was significantly increased in response to glutamate treatment, while ROS scavengers and ER chemical chaperones reduced Prx4 levels. Moreover, Prx4 overexpression reduces glutamate-induced apoptosis of HT22 cells by inhibiting ROS formation, Ca2+ influx, and ER stress. Therefore, we conclude that Prx4 has protective effects against glutamate-induced HT22 cell damage. Collectively, these results suggest that Prx4 could contribute to the treatment of neuronal disorders.

The Effect of Coffee Compsumption on Superoxide Dismutase (SOD) Enzyme Expression in Wistar Rats Induced by Hyper LDL

One of the causes of stroke is atherosclerosis. The incidence of occurrence ischemic stroke caused by atherosclerosis is 95%. Atherosclerosis is caused by oxidative stress in the endothelium due to the formation of Reactive Oxygen Species (ROS). Hyperlipidemia (hyper LDL) is one of the risk factors of elevated ROS. One of the enzymes that play a role in preventing the formation of ROS is superoxide dismutase (SOD). Coffee has a powerful antioxidant in which one of its active ingredients is chlorogenic acid that capable to inhibiting ROS formation. Fifteen wistar male divided into 3 groups. Group I (Control) were given standard fed, Group II (Hyperlipidemia) were given standart fed and hyperlipid diet, Group III (Coffee) were given standart fed and hyperlipid diet + coffee consumption. Treatment were done everyday for 30 days. Blood serum in each group was taken on day 30 and examined by ELISA superoxide dismutase (SOD). The results showed that superoxide dismutase levels in coffee group was significantly higher than hyperlipidemia group (p = 0,006). This study proves that coffee consumption can increase the production of superoxide dismutase enzyme.&#x0D; &#x0D; Keywords: atherosclerosis; coffee; hyperlipid; SOD

Effects of Gintonin-Enriched Fraction on Methylmercury-Induced Neurotoxicity and Organ Methylmercury Elimination.

Gintonin is a newly discovered ingredient of ginseng and plays an exogenous ligand for G protein-coupled lysophosphatidic acid receptors. We previously showed that gintonin exhibits diverse effects from neurotransmitter release to improvement of Alzheimer’s disease-related cognitive dysfunctions. However, previous studies did not show whether gintonin has protective effects against environmental heavy metal. We investigated the effects of gintonin-enriched fraction (GEF) on methylmercury (MeHg)-induced neurotoxicity and learning and memory dysfunction and on organ MeHg elimination. Using hippocampal neural progenitor cells (hNPCs) and mice we examined the effects of GEF on MeHg-induced hippocampal NPC neurotoxicity, on formation of reactive oxygen species (ROS), and on in vivo learning and memory functions after acute MeHg exposure. Treatment of GEF to hNPCs attenuated MeHg-induced neurotoxicity with concentration- and time-dependent manner. GEF treatment inhibited MeHg- and ROS inducer-induced ROS formations. Long-term treatment of GEF also improved MeHg-induced learning and memory dysfunctions. Oral administration of GEF decreased the concentrations of MeHg in blood, brain, liver, and kidney. This is the first report that GEF attenuated MeHg-induced in vitro and in vivo neurotoxicities through LPA (lysophosphatidic acids) receptor-independent manner and increased organ MeHg elimination. GEF-mediated neuroprotection might achieve via inhibition of ROS formation and facilitation of MeHg elimination from body.

Resveratrol, curcumin and gallic acid attenuate glyoxal-induced damage to rat renal cells

Glyoxal (GO), a by-product of glucose auto-oxidation, is involved in the glycation of proteins/ lipids and formation of advanced glycation (AGE) and lipoxidation (ALE) end products. AGE/ALE were shown to contribute to diabetic complications development/progression such as nephropathy. Diabetic nephropathy progression has an oxidative nature. Given the antioxidant effects of polyphenols, potential protective effects of resveratrol, curcumin and gallic acid, in rat renal cells treated with GO, were evaluated in the present work. According to our results, incubation of GO with the cells reduced their viability and led to membrane lysis, reactive oxygen species (ROS) formation, lipid peroxidation, mitochondrial membrane potential collapse, and lysosomal membrane leakage. These findings were prevented by pre-treatment with resveratrol, curcumin and gallic acid. Mitochondrial and lysosomal toxic interactions appear to worsen oxidative stress/cytotoxicity produced by GO. Resveratrol, curcumin and gallic acid inhibited ROS formation and attenuated GO-induced renal cell death.

Water extract of mangosteen suppresses H2O2-induced endothelial apoptosis by inhibiting oxidative stress

Excessive production of reactive oxygen species (ROS) is a major cause of endothelial apoptosis. Mangosteen extract has been shown to possess antioxidant properties. Mangosteen is commonly extracted either with semi-polar solvent, yielding virtually pure α-mangostin, or with water, yielding a low α-mangostin concentration but including a wide variety of other polyphenols present in the fruit. However, the effect of a water extract of mangosteen (ME) on ROS induced cell death is not yet known. This study evaluated whether ME suppresses H2O2 induced endothelial cell death and ROS production in human endothelial cell lines. The concentrations of ME and H2O2 were determined by MTT assay. Intracellular ROS levels were determined by DCF-DA assay, and cell death rates by MTT and TUNEL assays. MAPK and apoptotic proteins were analyzed by western blot. Results showed that ME concentrations of 1, 5 and 10 µg/ml were non-toxic. ME significantly attenuated ROS formation and cell death, both in a dose dependent manner. ME also reduced phosphorylation of p38 MAPK as well as cleavage of caspase 3 and PARP-1. In summary, ME demonstrates anti-apoptotic effects against H2O2 induced endothelial cell death by inhibiting ROS formation and suppressing p38 MAPK.

The Effects of Lysimachia christinae Hance Extract Fractions on Endothelium-Dependent Vasodilatation

Background: Endothelium-dependent dilatation is a predictor for vascular function. NADPH oxidase-derived O2– can inactivate nitric oxide and induce vascular injury. Method: The crude ethanolic extract of Lysimachia christinae Hance were separated out 4 fractions of different olarities by petroleum ether, ethyl acetate, n-butanol (NB), and aqueous. The endothelial integrity was appraised by vascular tension measurement. Dihydroethidium was utilized to observe the vascular reactive oxygen species (ROS) production. Western-blot was adopted to detect protein expression. Results: Among the 4 fractions of L. christinae Hance, the NB fraction showed the most potent capacity of promoting endothelium-dependent vascular relaxation and inhibiting ROS formation in aortic rings, which were likely attributed by suppressing the expression of NAD(P)H oxidase subunit (gp91phox, p47phox, and p67phox) and enhancing the phosphorylation of endothelial NOS in vascular tone. Conclusions: These results suggest that the NB fraction possess the strongest vascular pharmacological activities among the crude ethanolic extract of L. christinae Hance, which may help us for purifying bioactive constituents and discovering new drugs from this herb in future.

Rat Pial Microvascular Changes During Cerebral Blood Flow Decrease and Recovery: Effects of Cyanidin Administration.

The reactive oxygen species (ROS) are known to play a major role in many pathophysiological conditions, such as ischemia and reperfusion injury. The present study was aimed to evaluate the in vivo cyanidin (anthocyanin) effects on damages induced by rat pial microvascular hypoperfusion-reperfusion injury by cerebral blood flow decrease (CBFD) and subsequent cerebral blood flow recovery (CBFR). In particular, the main purpose was to detect changes in ROS production after cyanidin administration. Rat pial microvasculature was investigated using fluorescence microscopy through a cranial window (closed); Strahler's method was utilized to define the geometric features of pial vessels. ROS production was investigated in vivo by 2′-7′-dichlorofluorescein-diacetate assay and neuronal damage was measured on isolated brain sections by 2,3,5-triphenyltetrazolium chloride staining. After 30 min of CBFD, induced by bilateral common carotid artery occlusion, and 60 min of CBFR, rats showed decrease of arteriolar diameter and capillary perfusion; furthermore, increase in microvascular leakage and leukocyte adhesion was observed. Conversely, cyanidin administration induced dose-related arteriolar dilation, reduction in microvascular permeability as well as leukocyte adhesion when compared to animals subjected to restriction of cerebral blood flow; moreover, capillary perfusion was protected. ROS generation increase and marked neuronal damage were detected in animals subjected to CBFD and CBFR. On the other hand, cyanidin was able to reduce ROS generation and neuronal damage. In conclusion, cyanidin treatment showed dose-related protective effects on rat pial microcirculation during CBFD and subsequent CBFR, inducing arteriolar dilation by nitric oxide release and inhibiting ROS formation, consequently preserving the blood brain barrier integrity.