End Product Of Lipid Peroxidation Research Articles

The effects of copper pyrithione, an antifouling agent, on developing zebrafish embryos.

A substitute for the organotins has been the use of metal pyrithiones, principally zinc and copper (CuPT) as antifouling agents. Zebrafish, Danio rerio, embryos were exposed after fertilization to increasing concentrations of CuPT (2, 4, 8, 12, 16, 32 and 64 μg/L) for 24 h. Morphological abnormalities at 30, 96 and 120 hours post fertilization (hpf) were recorded. Abnormalities at concentrations of 12 μg/L and higher were observed. Notochords became severely twisted as concentrations increased. These distortions of the notochord originated in the tail at the lower concentrations and proceeded rostrally with increasing dose. Edema was observed in the cardiac and yolk sac regions at the 12 and 16 μg/L CuPT concentrations. Light microscopy showed disorganization of muscle fibers, disruption and distortion of the transverse myoseptum and vacuolization of the myocyte. Hatching was measured every 12 h for 5 days following the 24 h exposure. Hatching decreased in a dose dependent manner. At 120 hpf, 47 % of the 64 μg/L CuPT treated embryos hatched. Inductively coupled plasma atomic absorbance spectrophotometry (ICPAAS) revealed copper bioaccumulation in whole embryo tissue and was significantly elevated in 32 and 64 μg/L CuPT treatment groups as compared to controls. Lipid peroxidation end products were significantly increased in animals exposed to 32 and 64 μg/L of CuPT. These data demonstrate that oxidative stress may play a role in the toxicity. The abnormalities and deformities observed in fish larvae would significantly decrease survival in polluted aqua-systems and question the use of this product as an antifouling agent.

INFLUENCE OF SALICYLIC ACID ON COLD TOLERANCE OF CUCUMBER SEEDLINGS

The effect of the phytohormone salicylic acid (SA) on the tolerance of cucumber seedlings ( Cucumis sativus L.) to action of the low hardening (12 oС) and damaging (4 oС) temperatures was investigated. It was found that the effect of the temperature12 °C on seedlings untreated SA contributes to their hardening, as evidenced by decrease of electrolyte leakage from cotyledons. In contrast, the temperature4 °C had damaging effect on seedlings untreated SA, resulting in an increase of electrolyte leakage. It was also found that there was a decrease of content of the end product of lipid peroxidation (POL) - malondialdehyde (MDA) in leaves and free proline at effect of the temperature12 °C, and at the action of the temperature4 °C – their accumulation. Pretreatment of SA at concentrations of 50 and 100 μM reduced electrolyte leakage from cells of cucumber seedling leaves at the temperature 12 and4 °C. Furthermore, exogenous SA reduced POL leading to a decrease of the level of MDA and also contributed to the accumulation of free proline in cotyledon leaves at the normal temperature (22 °C) and in conditions of the low hardening (12 °C) and damaging (4 °C) temperatures. The data indicate the ability of SA to activate the processes aimed to improving cold tolerance of cucumber plants.

The Potential Use of Secondary Metabolites in Moringa oleifera as an Antioxidant Source

This present study determined antioxidant activity, lipid peroxidation, total phenolic, total flavonoids and phytochemicals in moringa leaves and moringa stem. Analysis used in this study was 1, 1-diphenyl-2-picrylhydrazyl (DPPH) method for antioxidant activity, thiobarbituric acid reactive substances (TBARS) method for lipid peroxidation, Folin-Ciocalteu method for total phenolic, total flavonoid and UFLC (Ultrafast Liquid Chromatography) for identification and quantification of phenolic compounds. The results showed that moringa leaves had higher ability to scavenge free radical, total phenolic, and total flavonoid than moringa stem (P<0.001). Malondialdehyde production, the end product of lipid peroxidation, in moringa leaves was lower than moringa stem (P<0.001). Ferulic acid was the major active compound in both moringa leaves and moringa stem. This present study indicated that moringa leaves and moringa stem could be used as feed additive which had a good potential to prevent oxidative stress in animals. Key words: antioxidant, lipid peroxidation, moringa leaves, moringa stem, phytochemicals

Src Tyrosine Kinase Activation by 4-Hydroxynonenal Upregulates p38, ERK/AP-1 Signaling and COX-2 Expression in YPEN-1 Cells.

4-Hydroxynonenal (4-HNE), a major end product of lipid peroxidation, is highly reactive and involved in various cellular processes, such as inflammatory signaling. However, to date, the mechanistic roles of 4-HNE in inflammatory signaling related to protein tyrosine kinases have not been elucidated. In the present study, we investigated the interaction between 4-HNE and Src (a non-receptor tyrosine kinase) for its involvement in the molecular modulation of the inflammatory signaling pathway utilizing the YPEN-1 cell system. Immunoprecipitation experiments showed that 4-HNE phosphorylates (activates) Src at Tyr416 via adduct formation. In addition, LC-MS/MS and a docking simulation model revealed an addiction site at the Cys248 residue of Src, resulting in the stimulation of downstream p38, ERK/AP-1 and cyclooxygenase-2 (COX-2) signaling in YPEN-1 cells. The role of 4-HNE-activated Src in downstream inflammatory signaling was further investigated using dasatinib (a Src inhibitor) and by siRNA knockdown of Src. p38 and ERK were directly regulated by Src, as revealed by immunoblotting of the phosphorylated forms of mitogen-activated protein kinases (MAPKs), which are key elements in the signaling transduction pathway initiated by Src. The study also shows that Src modulates the HNE-enhanced activation of AP-1 and the expression of COX-2 (a target gene of AP-1). Together, the results of this study show that 4-HNE stimulates Src tyrosine kinase in activation of the inflammation process.

Brassinosteroid alleviates chilling-induced oxidative stress in pepper by enhancing antioxidation systems and maintenance of photosystem II

To explore regulated mechanisms of Brassinosteroids-induced chilling tolerance, we studied the involvement of foliar sprayed 24-epibrassinolide (EBR) in the growth, lipid peroxidation, distribution of absorbed energy and excitation energy, chlorophyll fluorescence characteristics and antioxidant defense system of pepper seedlings under chilling stress. We found that low temperature retarded the growth of pepper seedlings, but foliar spray of EBR solution markedly improved the photoinhibition by increasing maximum quantum efficiency of photosystem II (Fv/Fm), the actual photochemical efficiency of photosystem II, photochemical quenching coefficient and the efficiency of excitation capture of open PSII center (Fv′/Fm′). Likewise, EBR increased the fraction of photochemical efficiency (P) and reduced the fraction of antenna heat dissipation (D) and excess energy (E). Low temperature led the increase in end product of lipid peroxidation and the content of H2O2, O2− and OH−, and it caused the occurrence of oxidative stress. The activities of antioxidative enzymes including superoxide dismutase, peroxidase, catalase and ascorbate peroxidase, and contents of ascorbic acid and reduced glutathione were significantly improved by EBR during low temperature stress. The application of EBR also markedly increased the contents of proline, soluble sugar and protein under low temperature. EBR significantly reinforced antioxidant defense system, and it can be reflected through the reduced accumulation of harmful reactive oxygen species and MDA in pepper seedlings. Overall, these results suggest that EBR increases the tolerance of pepper seedlings against chilling stress largely by optimizing distribution of absorbed energy and excitation energy and enhancing antioxidant defense system.

Abstract P125: Visceral Adipose Tissue-derived Serine Protease Inhibitor Prevents the Development of Hypertension Through the Inhibition of Vascular Remodeling via Anti-Oxidative Mechanisms in Spontaneously Hypertensive Rats

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an adipokine originally identified in visceral adipose tissue of obese type 2 diabetic Otsuka Long-Evans Tokushima Fatty rats. We have been focusing on the direct vascular effects of vaspin and found that vaspin inhibits: 1) tumor necrosis factor-α-induced inflammatory responses in vascular smooth muscle cells (SMCs) via the anti-oxidative mechanisms, 2) platelet derived growth factor-BB-induced migration of SMCs, 3) apoptosis of vascular endothelial cells (ECs) mediated by methylglyoxal, a metabolite of glucose. Since vascular remodeling via inflammation and migration of vascular SMCs as well as apoptosis of ECs is an important process for the development of hypertension, it is suggested that vaspin has preventive roles on the pathogenesis of hypertension. However, it is not revealed whether vaspin affects the development of hypertension in in vivo hypertensive model. The aim of the present study was to explore it. Five-week-old male spontaneously hypertensive rats (SHR) were received an intraperitoneal injection of vaspin (1 μg/kg) or saline once daily for four weeks. Age-matched male Wistar-Kyoto (WKY) rats were used as a control. Blood pressure (BP) was measured using a tail-cuff method weekly. Isolated superior mesenteric arteries were used for the examination of vascular structural changes by a hematoxylin and eosin staining. Reactive oxygen species (ROS) generation was examined by an immunohistochemical staining to 4-hydroxy-2-nonenal (4-HNE), an end-product of lipid peroxidation by ROS. Vaspin significantly inhibited age-dependent elevation of BP in SHR (from 165.5 ± 3.9 mmHg to 153.1 ± 2.5 mmHg, n = 3, P &lt; 0.05). Vaspin significantly inhibited vascular wall hypertrophy in SHR mesenteric artery (from 1.35±0.05 to 0.98±0.08-fold relative to WKY, n = 3, P &lt; 0.05). Moreover, vaspin inhibited an increase of 4-HNE-positive area to vessel area ratio in SHR mesenteric artery (from 13.1±4.4 % to 4.6±0.4 %, n = 3). The present results demonstrate that vaspin inhibits the increase of BP through inhibiting vascular remodeling via anti-oxidative mechanisms in SHR.

Toxic and essential metals in placenta and its relation with lipid peroxides/glutathione status in pre-term and full-term deliveries

Aims and Objectives: Pre-term birth is worldwide problem, little is known about oxidative stress in placental tissue due to metals exposure of women during pregnancy. To seek correlation between concentration of metals and redox status in placental tissue of women with pre-term delivery and compared with those of women with the full-term delivery.Materials and Methods: A hospital based case–control study was conducted, total 80 pregnant women were selected for this study i.e., 30 females who delivered pre-term babies (gestational age &lt;37 week) serve as study group and 50 females who delivered full term babies (gestational age &gt; 37 week) serve as control group. Concentrations of metals lead (Pb), cadmium (Cd), iron (Fe), zinc (Zn), and (Cu), malondialdehyde (MDA) end product of lipid peroxidation and glutathione (GSH) were measured in placenta of study group and control group. Data were analyzed using Students t- test, chi square and linear regression.Results: In preterm cases level of malondialdehyde (MDA) and metals (Cd and Pb) were significantly higher, while level of GSH and some metals (Fe, Zn and Cu) were significantly lower in pre-term cases when compared to full-term cases. There were significant positive correlations of placental metals (Pb and Cd) with MDA (p&lt;0.05), suggests that metals might have influenced pre-term deliveries.Conclusions: The results showed that elevated level of placental Cd and Pb induced oxidative stress which might implicate in pre-term deliveries and higher concentration of Zn and Cu may be concerned with the defence against oxidative stress in placental tissue of full-term cases.Asian Journal of Medical Sciences Vol.7(1) 2015 34-39

FEATURES OF LIPID PEROXIDATION-ANTIOXIDANT PROTECTION IN ADOLESCENT GIRLS IN DIFFERENT GROUPS OF HEALTH

Among the metabolic processes involved in the formation of physical and sexual development of adolescents recently the system of lipid peroxidation and antioxidant protection (LPO-AOP) supporting the redox state of organism and its adaptive response under the influence of different factors is highlighted. Background: The aim of this work is an analysis LPO-AOP-parameters in adolescent girls of different groups of health depending on where they live. Patients and methods: We examined 143 girls aged 15–17 years who had the second and the third groups of health and lived in the village and the city. For assessment of LPO-AOP parameters spectrophotometric, spectrofluorometric and statistical methods were used. Results: The combination of high concentration of unsaturated lipids with primary accumulation of lipid peroxidation products and the stable level of the end products of lipid peroxidation were found in girls rural both groups of health. State of the antioxidant defense system in girls of the village was characterized by a high content of its components, except for α-tocopherol. It concentration was reduced in girls of the third group of health. The levels of lipid peroxidation secondary intermediats were elevated and oxidized glutathione level was reduced in city girls of the third groups of health. Conclusion: The usage of oxidized glutathione for the prevention of exacerbations of chronic diseases in city girls of the third group of health is recommended.

Ultrasensitive UPLC–MS/MS method for analysis of etheno-DNA adducts in human white blood cells

Etheno-DNA adducts are generated by interaction of cellular DNA with exogenous environmental carcinogens and end products of lipid peroxidation. It has been determined that 1,N6-etheno-2’-deoxyadenosine (εdA) and 3,N4-etheno-2’-deoxycytidine (εdC) adducts formed in human white blood cells can be used to serve as biomarkers of genetic damage mediated by oxidative stress. In this study, we developed an ultrasensitive ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method used to detect and quantify εdA and εdC adducts in human white blood cells. The percent recoveries of εdA and εdC adducts were found to be 88.9% ± 2.8 and 95.7% ± 3.7, respectively. The detection limits were ∼1.45 fmol for εdA and ∼1.27 fmol for εdC in 20 μg of human white blood cell DNA samples, both εdA and εdC adducts could be detected using only ∼ 5 μg of DNA per sample. For validation of the method, 34 human blood cell DNA samples were assayed and the results revealed a significant difference (P < 0.01) between levels (fmol/μg DNA) of 0.82 ± 0.83 (standard deviation [SD]) (range: 0.15–3.11) for εdA, 3.28 ± 3.15 (SD) (range: 0.05–9.6) for εdC in benzene-exposed workers; and 0.04 ± 0.08 (SD) (range: 0.0–0.27) for εdA and 0.77 ± 1.02 (SD) (range: 0.10–4.11) for εdC in non-benzene-exposed workers. Our method shows a high sensitivity and specificity when applied to small amounts of human white blood cell DNA samples; background levels of εdA and εdC could be reproducibly detected. The ultrasensitive and simple detection method is thus suitable for applications in human biomonitoring and molecular epidemiology studies.

PP.13.26

Objective: Moderate zinc deficiency during intrauterine and postnatal growth is a fetal programming model of hypertension, renal and cardiovascular dysfunction. Male zinc deficient rats showed reduced left ventricular (LV) wall thickness and ejection fraction. The aim of this study was to evaluate, nitric oxide (NO) system, pro-inflammatory cytokines and oxidative state in LV of adult male rats exposed to this deficiency. Design and method: Wistar rats received during pregnancy up to weaning low (L:8 ppm) or control (C:30 ppm) zinc diet. After weaning, male offspring fed low (l) or control (c) zinc diet during 60 days (Cc, Ll, Lc). At day 81, we evaluated in LV: Interleukin-6 and Tumor Necrosis Factor-α (IL-6, TNF-α), basal NO synthase (NOS) and endothelial (eNOS), neuronal (nNOS) and inducible (iNOS) isoforms activities; eNOS and Ser1177 eNOS phosphorylation protein expression (eNOS/β-actin, pSer1177eNOS/eNOS), mRNA expression (eNOS/GAPDH) and lipid peroxidation end products levels (TBARS). Values are means ± SEM, n = 6/group. One way ANOVA, Bonferroni post-test. Results: *p < 0.01vs Cc; †p < 0.01vs Ll. NO production is mainly produced by eNOS, because basal NOS activity was not affected by nNOS and iNOS inhibitors, but was decreased by blocking Ca2+-calmodulin in all groups.Conclusions: Zinc deficiency during fetal and postnatal life programs a lower production and bioavailability of cardiac NO due to decreased activity and pSer1177 of eNOS and increased oxidative stress. Oxidative stress and NO impairment, jointly with higher levels of pro-inflammatory cytokines, could contribute to the cardiac disorders observed in adult males. Adequate zinc diet after weaning was unable to totally avoid the cardiac alterations induced during fetal life.

The Effect of a Nanostructured Chitosan–Bee Venom–Gold Nanoparticle System on Free Radical Process Activity, Blood System Adaptation, and Tumor Growth in Rats with Transplanted Cancer PC-1

The aim of the investigation was to estimate by blood system indices adaptogenic and antioxidant properties, as well as anti-tumor efficiency of nanostructured chitosan–bee venom–gold nanoparticles on laboratory animals with transplanted РС-1 strain. Materials and Methods. We studied the impact of a nanopreparation — chitosan–bee venom–gold nanoparticles — on antioxidant, adaptogenic, antitumor effects when injected to animals (35 white rats) with transplanted liver cancer РС-1 (alveolar hepatic cancer). In time course of the experiment we analyzed physiological and biochemical blood values. On day 28 following preparation injection we determined the area of external tumor surface of the study animals and controls. Results. We conducted a comparative assessment of free radical oxidation by the number of lipid peroxidation end products and antioxidant system activity in blood plasma, as well as a stress level by white cell count and leukocyte ratio, and the area of tumor external surface in laboratory animals after the course of treatment with the preparation. We revealed antitumor, antioxidant and adaptogenic activity of a chitosan–bee venom–gold nanoparticles preparation. Conclusion. A nanostructured preparation (chitosan–bee venom–gold nanoparticles) in therapeutic doses (one order less than toxic ones) effectively inhibits transplanted tumor PC-1 growth (alveolar hepatic cancer) exhibiting significant antioxidant and adaptogenic activity.

Curcumin alleviates cisplatin-induced learning and memory impairments

The present study has been designed to investigate the role of curcumin on cisplatin-inducedcognitive impairment and to reveal mechanisms of cisplatin’s detrimental actions on cognition in rats. Animals were treated with cisplatin (5mg/kg/week) and/or curcumin (300mg/kg/day) for 5weeks. Morris water maze test was used to assess spatial learning and memory. Enzymatic activities of acetylcholinesterase (AChE) and superoxide dismutase (SOD) were evaluated from hippocampus and plasma samples, and malondialdehyde (MDA), which is the end-product of lipid peroxidation, was determined by a colorimetric method. Our results showed that cisplatin (5mg/kg/week, 5weeks) caused learning and memory deficits, elevated MDA content, decreased SOD activity in the hippocampus and plasma, and AChE activity in the hippocampus. Curcumin improved learning and memory in rats with administration of cisplatin. In addition, curcumin significantly reduced the level of MDA and increased the activities of SOD and AChE. Taken together, our findings indicate that curcumin ameliorates cisplatin-induced spatial learning and memory impairment, possibly through restored cholinergic function and enhanced oxidative status.

Malondialdehyde levels and total antioxidant capacity in the dental follicles of the asymptomatic impacted third molars

Objectives: Malondialdehyde (MDA), is one of many low molecular weight end products of lipid peroxidation (LPO), increases in oxidative stress. Antioxidants such as total antioxidant capacity (TAC) have a protective effect against reactive oxygen species. The aim of this study is to examine the development of the antioxidant defense mechanism in dental follicles (DF) of radiologically asymptomatic impacted third molars (ITM) by using MDA and TAC. Materials and Methods: This study involved 40 DF of 40 patients referred for clinically and radiographically asymptomatic ITM. 40 healthy gingival tissues in the same patients obtained during surgical removal of teeth as a control group. This study involved DF widths on periapical radiographs narrower than 2.5 mm were included in the study. All of tissues samples were analyzed for MDA and TAC. Results: Levels of the MDA and TAC in DF were significantly higher than the levels of MDA and TAC provided from healthy gingival tissues of the same patients (p<0.05). Conclusions: The results of our study showed that an important antioxidant defense mechanism may also occur in DFs of asymptomatic ITM. In the light of these preliminary findings of the presented study, supplementary studies should be undertaken to establish the differences between inflammation affecting the DF and clinical outcomes.

Inhibitory Effect of Musa paradisiaca on Enzymes Linked to Diabetes and Hypertension

The purpose of this study was to determine whether unripe plantain products has hypoglycemic properties by comparing its potency with commercial drug (arcabose) on key enzymes linked to diabetes (α‐amylase and α‐glucosidase) and hypertension [(Angiotensin‐I Converting Enzyme) (ACE)]Diabetes was induced by combined feeding of the adult male Wistar rats with High fat diet (Lard) plus intraperitoneal injection of streptozotocin (25 mg/kg body weight). After sacrifice, the pancreas was examined for α‐amylase, α‐glucosidase angiotensin‐1 converting enzyme. The plasma obtained was also studied by testing for GST, GSH and Malonadialdehyde (MDA) activities. The diabetic rats showed elevated (P&lt;0.05) levels of α‐amylase, α‐glucosidase and ACE and MDA (end product of lipid peroxidation). However, the effect of treatment of unripe plantain products supplement diets on diabetic rats (after 30 days) was significantly (P&lt;0.05) reversing the above mentioned parameters toward normalcy.These results imply that there is more to unripe plantain than mere consumption. It also brings about a new dimension to the management of diabetes and its attendant complications.

Impact of Moderate Zinc Deficiency During Fetal Life and Postnatal Growth on Cardiac Nitric Oxyde System, Inflammatory and Oxidative Markers in Adult Male Rats

Moderate zinc deficiency during fetal and postnatal growth programs cardiovascular dysfunction and hypertension. Male zinc deficient rats showed reduced left ventricular (LV) wall thickness and ejection fraction. Aim: to evaluate nitric oxide (NO) system, pro‐inflammatory cytokines and oxidative state in LV of adult male rats exposed to this deficiency. Wistar rats received during pregnancy up to weaning low (L:8 ppm) or control (C:30 ppm) zinc diet. After weaning, male offspring fed low (l) or control (c) zinc diet during 60 days (Cc, Ll, Lc). At day 81, we evaluated in LV: Interleukin‐6 and Tumor Necrosis Factor‐α (IL‐6;TNF‐α), basal NO synthase (NOS) and endothelial, neuronal and inducible (eNOS;nNOS;iNOS) isoforms activities; eNOS and Ser1177 eNOS phosphorylation protein expression (eNOS/β‐actin; pSer1177eNOS/eNOS), mRNA expression (eNOS/GAPDH) and lipid peroxidation end products (TBARS). Means±SEM, n=6/group. One way ANOVA, Bonferroni post‐test. Cc Ll Lc TNF‐α (immunohistochemistry;% of positive staining/area) 1.4±0.4 20.4±2.0* 1.7±0.3 IL‐6 (immunohistochemistry; % of positive staining/area) 1.8±0.3 21.1±1.7* 2.8±0.8 Basal NOS Activity (pmol14C L‐citrulline/g tissue.min) 204±6 164±10* 157±11* Basal NOS+iNOS inhibitor (Aminoguanidine; pmol14C L‐citrulline/g tissue.min) 216±7 166±8* 163±9* Basal NOS+nNOS inhibitor (7‐nitroindazole; pmol 14C L‐citrulline/g tissue.min) 209±10 166±8* 164±9* Basal NOS+Ca2+‐calmodulin inhibitor (Calmidazolium; pmol 14C L‐citrulline/g tissue.min) 47±2# 52±2# 49±2# pSer1177eNOS/eNOS (Western Blot; optical density relative to Cc) 1.00±0.02 0.74±0.03* 1.02±0.16 TBARS (nmol/mg protein) 0.21±0.02 0.78±0.08* 0.47±0.02*† No differences were found in eNOS protein and mRNA expression.*p&lt;0.01vsCc;†p&lt;0.01vsLl;#p&lt;0,01vs basal NOS.Zinc deficiency during fetal and postnatal life programs a lower production and bioavailability of cardiac NO due to decreased activity and pSer1177 of eNOS and increased TBARS. These alterations, jointly with higher levels of IL‐6 and TNF‐α, could contribute to the cardiac disorders previously observed. Supported by:UBA‐CONICET

The Allosteric Heat Shock Protein Inhibitor YM‐01 Protects Against Alcohol‐Induced Growth Arrest

BackgroundOxidative stress is implicated in the pathogenesis of alcohol‐induced liver injury. This is, in part, mediated by the cytochrome P450 CYP2E1 which contributes to reactive oxygen species (ROS) production. YM‐01, a derivative of MKT‐077, is an allosteric heat shock protein inhibitor and modulator of the triage function of heat shock cognate protein 70 (HSC70) and may protect cells from oxidative stress. In this study, we investigated the effect of YM01 on ethanol‐induced growth arrest.MethodsHepG2 cells overexpressing CYP2E1 (E47) were pretreated with either vehicle or YM‐01 then treated with arachidonic acid (60 µM for 18 hrs), followed by iron nitrilotriacetic acid (Fe‐NAT, 25 µM for 5 hrs), and finally with ethanol (100 mM for 48 hrs). MTT and western analysis was then performed.ResultsIn the CYP2E1‐expressing ethanol‐treated cells, cell growth was arrested as determined by cell viability (MTT assay). This arrest was relieved by treatment with YM‐01. Further, western analysis showed that pretreatment with YM‐01 prevented 4‐hydroxynonenal (4‐HNE) adduct formation induced by ethanol (the most abundant lipid peroxidation end product). In addition, we determined ubiquitination levels by Western analysis to determine role of the ubiquitin‐proteasome pathway.ConclusionThis study indicates that YM‐01 decreases 4‐HNE adduct formation in CYP2E1‐expressing cells and protects against alcohol induced cell growth arrest.

Effects of TiO2 and Co3O4 Nanoparticles on Circulating Angiogenic Cells

Background and AimSparse evidence suggests a possible link between exposure to airborne nanoparticles (NPs) and cardiovascular (CV) risk, perhaps through mechanisms involving oxidative stress and inflammation. We assessed the effects of TiO2 and Co3O4 NPs in human circulating angiogenic cells (CACs), which take part in vascular endothelium repair/replacement.MethodsCACs were isolated from healthy donors’ buffy coats after culturing lymphomonocytes on fibronectin-coated dishes in endothelial medium for 7 days. CACs were pre-incubated with increasing concentration of TiO2 and Co3O4 (from 1 to 100 μg/ml) to test the effects of NP – characterized by Transmission Electron Microscopy – on CAC viability, apoptosis (caspase 3/7 activation), function (fibronectin adhesion assay), oxidative stress and inflammatory cytokine gene expression.ResultsNeither oxidative stress nor cell death were associated with exposure to TiO2 NP (except at the highest concentration tested), which, however, induced a higher pro-inflammatory effect compared to Co3O4 NPs (p<0.01). Exposure to Co3O4 NPs significantly reduced cell viability (p<0.01) and increased caspase activity (p<0.01), lipid peroxidation end-products (p<0.05) and pro-inflammatory cytokine gene expression (p<0.05 or lower). Notably, CAC functional activity was impaired after exposure to both TiO2 (p<0.05 or lower) and Co3O4 (p<0.01) NPs.ConclusionsIn vitro exposure to TiO2 and Co3O4 NPs exerts detrimental effects on CAC viability and function, possibly mediated by accelerated apoptosis, increased oxidant stress (Co3O4 NPs only) and enhancement of inflammatory pathways (both TiO2 and Co3O4 NPs). Such adverse effects may be relevant for a potential role of exposure to TiO2 and Co3O4 NPs in enhancing CV risk in humans.

Investigation into the Effects of Boron on Liver Tissue Protein Carbonyl, MDA, and Glutathione Levels in Endotoxemia.

Endotoxin has been known to cause the formation and damage of free radical. The importance of boron for human life is increasing each passing day, and its consuming fields are continuing to expand due to the advances in science and technology. Therefore, in our study, we intended to investigate into the effects of boron on liver tissue oxidative events. Eighteen male Wistar albino rats were randomly separated into three equal groups in the experiments; control group, boron + endotoxin group, and endotoxin group. Dissolved in distilled water, boric acid (100 mg/kg) was administered to boron + endotoxin group via gavage procedure for 28 days. Only distilled water was administered to control and endotoxin groups via gavage procedure for 28 days. Then 4 mg/kg endotoxin (LPS; Escherichia coli 0111:B4) was intraperitoneally (ip) administered to boron + endotoxin and endotoxin groups on the 28th day. Sterile saline was injected into control group on the 28th day (ip). Malondialdehyde (MDA), which is the end product of lipid peroxidation in liver tissues, protein carbonyl compounds (PC), which are protein oxidization markers, and glutathione (GSH) levels were measured spectrophotometrically. The results were compared with Mann-Whitney U test. When boron + endotoxin group is compared with endotoxin group, PC levels of endotoxin group showed a significant increase. When GSH levels are compared, GSH level in boron + endotoxin group decreased according to endotoxin group. Variations among all groups in MDA levels were found to be statistically insignificant. We are of the opinion that endotoxin affects the proteins by forming free radicals, and boron may also cause the structural and/or functional changes in proteins in order to protect proteins from oxidization.

Quercetin alleviates 4-hydroxynonenal-induced cytotoxicity and inflammation in ARPE-19 cells

Retinal pigment epithelium (RPE) plays the principal role in age-related macular degeneration (AMD), a progressive eye disease with no cure and limited therapeutical options. In the pathogenesis of AMD, degeneration of RPE cells by multiple factors including increased oxidative stress and chronic inflammation precedes the irreversible loss of photoreceptors and central vision. Here, we report that the plant-derived polyphenol, quercetin, increases viability and decreases inflammation in stressed human ARPE-19 cells after exposure to the lipid peroxidation end product 4-hydroxynonenal (HNE). Several previous studies have been conducted using the direct oxidant H2O2 but we preferred HNE since natural characteristics predispose RPE cells to the type of oxidative damage evoked by lipid peroxidation. Quercetin improved cell membrane integrity and mitochondrial function as assessed in LDH and MTT tests. Decreased production of proinflammatory mediators IL-6, IL-8, and MCP-1 were indicated at the RNA level by qPCR and at the protein level by the ELISA technique. In addition, we probed the signaling behind the effects and observed that p38 and ERK MAPK pathways, and CREB signaling are regulated by quercetin in ARPE-19 cells. In conclusion, our present data suggests that HNE is highly toxic to serum-starved ARPE-19 cells but quercetin is able to reverse these adverse effects even when administered after an oxidative insult.

Sesamin suppresses STZ induced INS-1 cell apoptosis through inhibition of NF-κB activation and regulation of Bcl-2 family protein expression

Diverse risk factors for diabetes can induce oxidative stress, leading to pancreatic beta cell damage and insulin secretion dysfunction. In the present study, we evaluated the effect of sesamin on streptozotocin (STZ) induced apoptosis in INS-1 cells and the possible mechanisms implicated. After preincubation with indicated concentrations of sesamin (0.1, 1.0 and 10.0μmol/l) for 24h, INS-1 cells were exposed to STZ (3mmol/l) for 12h. Sesamin effectively improved STZ induced cell damage as determined by MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide] assay and insulin secretion capacity, and suppressed STZ induced cell apoptosis as evaluated by flow cytometry using annexin V and propidium iodide double staining. Western blot analysis demonstrated that sesamin markedly suppressed STZ induced nuclear factor kappa B (NF-κB) activation, with Bax protein down-regulated and Bcl-2 protein up-regulated significantly. Preincubation with sesamin resulted in an evident enhancement of total antioxidant capacity in INS-1 cells, accompanied by a significant reduction of intracellular reactive oxygen species and malondialdehyde, an end product of lipid peroxidation. Taken together, these findings suggested that sesamin was capable of suppressing STZ induced INS-1 cell apoptosis, which might be ascribed, at least partly, to the inhibition of NF-κB activation and subsequent regulation of Bcl-2 family protein expression. This study would provide a potential target for treatment of diabetes with sesamin as well as other antioxidants.