Erythrocyte Lipid Peroxidation Research Articles

LED THERAPY IN SKIN REPAIR MODULATES CYTOKINE LEVELS AND OXIDATIVE STRESS

<h3>Objectives</h3> To evaluate the effect of light emitting diode (LED) therapy in skin wound healing. <h3>Study Design</h3> 55 male Wistar rats were divided into 3 groups: negative control (<i>n</i> = 5; with no injury and without treatment), sham (with injury and without treatment), and LED groups. One full-thickness dorsal skin wound was created. The LED group received daily treatment. After 3, 5, 10, 14, and 21 days, euthanasia was performed for clinical, morphologic, oxidative stress (erythrocyte lipid peroxidation products (MDA), antioxidant enzymes superoxide dismutase (SOD) and glutathione (GSH)), and cytokine analyses (IL-1β, IL-10, and tumor necrosis factor alpha [TNF-α]). <h3>Results</h3> Clinically, at day 10, the LED therapy promoted faster tissue repair than the sham group (<i>P</i> < .05). Histopathologic evaluations showed that in 3 and 10 days, the LED group exhibited more advanced resolution of inflammatory processes compared to the sham group. MDA was lower and GSH was higher in the LED group in all experimental periods. SOD was higher at 10 days and lower at 5 and 21 days (<i>P</i> < .01). On day 10 there was a significant difference in the levels of IL-1β, IL-10 (<i>P</i> < .05), and TNF-α (<i>P</i> < .01). <h3>Conclusions</h3> LED therapy has antioxidant action and modulates inflammatory cytokines but had limited clinical results with the parameters used.

Fish biomarker responses reflect landscape anthropic disturbance in savanna streams.

Disturbance in the landscape surrounding streams can interfere with water quality and cause harm to aquatic organisms. In this study, we evaluate the influence of land use on the genetic and biochemical biomarkers of fish in streams of Brazilian savanna (Cerrado). We also evaluated whether biomarker responses are seasonally consistent. For this purpose, individuals of the Neotropical tetra fish Astyanax lacustris were exposed in cages for 96h, in 13 streams draining agroecosystems with different degrees of disturbance during the dry and wet seasons. After exposure, blood, liver, and gills were collected for multibiomarker analyses (micronuclei, erythrocytic nuclear abnormalities, lipid peroxidation, antioxidant enzymes, and biotransformation enzyme). The results showed that the gradient of anthropic disturbance was positively associated with genotoxic damage (erythrocytic nuclear abnormalities) and negatively associated with antioxidant and biotransformation enzymes of the liver in both seasons. No association of the gradient of anthropic disturbance with the frequency of micronuclei and for most gill enzymes was found for both seasons. Landscape disturbance was also negatively associated with water quality in the wet season. These results indicate that changes in land use interfere with the genetic and biochemical processes of organisms. Thus, the multibiomarker approach may represent an effective strategy for assessing and monitoring terrestrial landscape disturbance.

Antioxidant system and lipid peroxidation in rat erythrocytes under low-dose exposure to mercury acetate

BACKGROUND: Low-dose exposure of mercury compounds to the human body for a long time leads to the accumulation of a toxicant in tissues, causing damage to health. Mercury can be delivered to a developing fetus through the placenta or to an infant through breast milk. Erythrocytes are the preferred cell for mercury accumulation, reaching a concentration 20 times higher than the concentration in blood plasma. Erythrocytes have powerful antioxidant protection. The antioxidant protection system of the cell plays an important role in maintaining of homeostasis in the cell. Despite of the apparent vastness of researches of the antioxidant system and lipid peroxidation, changes after subacute poisoning with heavy metals have not been sufficiently studied.&#x0D; AIM: Study changes in biochemical parameters in Wistar rats erythrocytes with subacute poisoning with mercury acetate.&#x0D; MATERIALS AND METHODS: 30 days and 44 days after the administration of mercury acetate at a dose of 4 mg/kg in the hemolysate of red blood cells of rats, the indicators of the antioxidant system and lipid peroxidation were determined.&#x0D; RESULTS: The administration of mercury acetate for 30 days significantly increased the activity of SOD, GP and reduced the activity of GT. An increase of DC concentration was noted. 14 days after the end of the injection of the toxicant, the imbalance of the AOS enzyme link persists. An increase of DC and MDA concentrations was revealed.&#x0D; CONCLUSIONS: The data obtained demonstrate a violation of the antioxidant balance in erythrocytes after a 30-day administration of mercury acetate. 14 days after the end of the injection of the toxicant, changes in the enzyme link of AOS persist. Intensification of the processes of lipoperoxidation of erythrocyte membranes has been established. In the delayed period after poisoning, there is a tendency to disturbance the balance of AOS of erythrocytes, the intensity of LPO processes increases.

Age-and sex-related changes in selected hematological parameters, lipid peroxidation and erythrocytes osmotic fragility of Turkish Angora cats

This study was conducted to investigate the changes in selected hematological parameters, lipid peroxidation and osmotic fragility of erythrocytes in Angora cats depending on the age and gender. For this purpose, the blood samples were collected from 9 young and 14 adult cats which also classified as male (n=12) and female (n=11). Following hematological analysis, samples were washed with PBS by centrifugation and 10% hematocrit suspension was prepared from the erythrocytes pellet for osmotic fragility test. The concentration of malondialdehyde (MDA) was also measured from lysed erythrocyte to determine lipid peroxidation level. Red blood cells (RBCs), hemoglobin, and hematocrit were high in adults while mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were high in young cats. Erythrocyte MDA level was also higher in adult cats than in young cats. There was no significance in these parameters between male and female cats. Findings of fragility tests were showed that erythrocytes of young and male cats were more susceptible to hypotonic NaCl solutions than those of adult and female cats, respectively. It was concluded that erythrocytes related parameters in Angora cats changed depending on the age rather than gender except stability of RBCs.

Blood biochemistry and antioxidant status altered by anthropogenic impact in Adélie penguins (Pygoscelis adeliae).

Human activities are increased in Antarctica during decades, primarily due to the logistic and tourism operations, which consequent negative impact on penguin populations, altering their physiological responses. Therefore, we aimed to assess the blood biochemistry and oxidant/antioxidant balance of Adélie penguins (Pygoscelis adeliae) inhabiting two selected colonies: Potter Peninsula, considered as a low impacted colony, and Esperanza/Hope Bay as a high impacted colony. The levels of calcium, uric acid, and fructosamine, showed significant high values (p<0.05) for the Potter Peninsula´s penguins. Besides, this population showed high levels of plasma protein oxidation and erythrocyte lipid peroxidation (p<0.005) while the Esperanza/Hope Bay population presented high levels of erythrocyte protein oxidation and plasma lipid peroxidation (p<0.005). The oxidative damage values were similar in the Potter Peninsula population and slightly lower in the Esperanza/Hope Bay penguins if the results were compared to previous reports. The enzymes superoxide dismutase and glutathione peroxidase had significantly (p<0.005) high activity in the Esperanza/Hope Bay population, which also showed high reduced glutathione levels. The glutathione S-transferase activity was significantly high (p<0.005) in the Potter Peninsula population. The obtained results might take into account for making decisions about management and protection plans for the different penguin nesting areas in Antarctica.

The effect of ethomerzol fumarate on the antioxidant system and lipid peroxidation of rat erythrocytes during mercury acetate poisoning

The effect of ethomerzol fumarate on the antioxidant system and lipid peroxidation of rat erythrocytes during mercury acetate poisoning

Effect of silymarin on blood coagulation profile and osmotic fragility in carbon tetrachloride induced hepatotoxicity in male Wistar rats

Reports about the impact of Carbon tetrachloride (CCl4) hepatotoxicity on coagulation profile have been inconsistent. Multiple investigators have however demonstrated the effectiveness of silymarin in the resolution of anomalies induced by CCl4, although the effect of silymarin on the impact of CCl4 hepatotoxicity, especially coagulation profile and osmotic fragility have not been investigated. The liver, the primary site for the secretion of coagulation proteins, can become impaired in CCl4 hepatotoxicity, and silymarin reportedly increases hepatic protein synthesis as part of its hepatoprotective mechanism. This study assessed the effect of silymarin on blood coagulation profile and erythrocyte osmotic fragility in CCl4 induced hepatotoxicity in rats. Twenty male Wistar rats were allocated into four groups (n = 5) at random, namely: Control, CCl4 given CCl4 (1 ml/kg) administered intraperitoneally twice a week, Silymarin (S) given silymarin (100 mg/kg/day) orally, and S+CCl4 given silymarin (100 mg/kg/day) orally and (1 ml/kg) CCl4 one hour after, intraperitoneally twice a week for a duration of four weeks. Results showed protraction of activated partial thromboplastin time and thrombin time, increased erythrocyte osmotic fragility, liver damage, dyslipidemia, oxidative stress and lipid peroxidation in rats given CCl4. Silymarin attenuated most of these effects as observed from comparison between CCl4 and S+CCl4 rats. The findings of this study suggests that pretreatment with silymarin attenuated disruption in coagulation profile and erythrocyte osmotic fragility in CCl4 induced hepatotoxicity in Wistar rats.

Oxidative Stress Markers in COPD Patients Admitted to Pulmonary Rehabilitation

Background: Chronic obstructive pulmonary disease (COPD) is a pathology, which leads to an irreversible and progressive reduction of the airflow, usually caused by smoking, but only present in 25% of smokers. Some mechanisms involved in the onset and progression of the disease are local and systemic factors such as inflammation, exacerbated immune response and the appearance of oxidative stress. For all these reasons, the use of oxidative stress parameters as progression markers or even as a way to monitor the response of any kind of non-pharmacological interventions, like the use of pulmonary rehabilitation (PR), is feasible. Aims: The study aims to determine markers of oxidative stress levels in plasma and erythrocytes in patients with COPD through the application of a PR protocol. Methods: The study included 25 patients diagnosed with COPD according to the GOLD criteria with a medical indication of PR and attendance at the gym in San José Hospital, Santiago, Chile. Blood samples were obtained before the start of the protocol, in the 10th session, and at the end of the protocol (20th session). These samples were stored for oxidative stress determinations: FRAP (ferric reducing ability of plasma), F2-isoprostanes, reduced (GSH)/oxidized (GSSG) ratio and antioxidant enzyme activity in the erythrocyte. In all stages, associations between events and clinical parameters in patients have been observed. The clinical parameters assessed were the six-minute walking test (6MWT), maximal inspiratory and expiratory pressure, the BODE index and Saint George’s respiratory questionnaire, which includes quality of life. Results: The intracellular and extracellular capacity (GSH/GSSG and FRAP) in patients in PR at the 10th session were 53.1 and 34% higher than basal values, respectively. Only the GSH/GSSG ratio was 38.2% lower at the 20th session, related in part with higher plasma and erythrocyte lipid peroxidation at baseline. This could be due to the high concentration of reactive oxygen species in the first sessions, which has been reported in the literature as the acute effect of controlled exercise. Blood lipid peroxidation was 43.34 and 58.34% lower at the 10th and 20th sessions, respectively, demonstrating the improvements in the oxidative parameters with long-term exercise. With respect to oxidative enzyme activity, superoxide dismutase and catalase showed higher values of activity at the 10th and 20th sessions compared to the baseline. In the clinical parameters of the PR, significant changes were found in the BODE index and Saint George’s questionnaire, with these results being associated with a less predictive mortality score and a better understanding of the disease. This may be because the patients achieved longer distances in the 6MWT and better understood the disease at the end of the PR. Conclusion: The goal of this study was to contribute to the pathophysiological basis for further research on COPD patients, a disease of high prevalence in Chile. This study could support the basis for non-pharmacological strategies such a PR.

Protective Effect of Melatonin Against Malathion Induced Alterations in Antioxidant Defense System and Morphology of Erythrocytes in Wistar Rats

Malathion intoxication has been shown to produce oxidative stress due to the generation of free radicals and alter the antioxidant defense system in erythrocytes. Previous studies have shown the ameliorative role melatonin against oxidative stress induced by generation of free radicals. Present study was designed to investigate the protective effect of melatonin against malathion induced oxidative stress. For this purpose, male Wistar rats were randomly divided into four groups: Control; Melatonin (10mg/Kg body weight) group; Malathion (250mg/Kg body weight) treated group; Malathion + Melatonin treated group. Animals were administered an acute dose of malathion orally. The result of this study shows that in vivo administration of malathion caused inhibition in AChE activity in erythrocytes. Malathion intoxication also significantly increased the oxidative damage as evidenced by increased level of LPO and GSH content. The Inhibition of GSH level and increased lipid peroxidation in erythrocytes was relieved in malathion + melatonin group. Enhanced activities of SOD, CAT, GR and GPx were observed in erythrocytes of malathion treated rats as compared to control group. Moreover, melatonin supplementation in malathion treated rats maintain normal level of antioxidant enzymes as compared to malathion treated rats which indicates that melatonin provide protection against malathion-induced oxidative stress in erythrocytes. No significant change in the membrane bound enzymes such as Na+/K+-ATPase, Mg2+-ATPase and Ca2+-ATPase was observed in malathion intoxicated rats. Findings of scanning electron micrographs of erythrocytes revealed that both the malathion treated and malathion+melatonin treated groups exhibited morphological changes in erythrocytes. However, concomitant melatonin supplementation normalized the morphological alterations in erythrocytes induced by malathion toxicity. In conclusion, melatonin supplementation may ameliorate malathion-induced oxidative imbalance by enhancing the glutathione level, reducing lipid peroxidation and normalizing antioxidant enzyme activities in erythrocytes.

The Efficacy of a Peptide Product from the Pituitary Gland of &lt;i&gt;Rangifer tarandus&lt;/i&gt; as an Antioxidant Agent Under the Combined Effects of Light Desynchronosis and Depriming Toxicant

The possibility of using methods for determining the oxidative status of an organism (enzymatic and non-enzymatic links of the cellular antioxidant system) to assess the antioxidant properties of peptides of the pituitary gland of the reindeer (Rangifer tarandus) were investigated in an experimental study conducted with a combined effect of factors of different nature on rats: a physical factor — prolonged light desynchronosis (different light modes) and a chemical factor - acute severe poisoning with depriving toxicant (sodium thiopental, LD50). The pharmacological correction of the oxidative status of cells in the animals of the experimental subgroups was carried out with the peptide product of the pituitary gland, intranasally injecting the surviving rats with the bioproduct at a dose of 100 µg/kg, once in the first half of the objective day for 14 days after poisoning with sodium thiopental. The surviving animals of the control groups were similarly injected with saline. The effectiveness of the correction of the disruptions of the cellular oxidative status with the peptide product of the pituitary gland was tested 30 days after the onset of the combined effect of stress factors on rats. It was found that the use of this bioactive peptide product in experimental animals exposed to different light modes and a chemical factor contributed to a decrease in the initially increased indicators of lipid peroxidation in rat erythrocytes and an increase in the initially reduced indicators of the enzymatic link of antioxidant protection. The activity of superoxide dismutase, glutathione peroxidase, glutathione transferase, as well as glucose-6-phosphate dehydrogenase increased after pharmacological correction. The concentration of reduced glutathione also increased in erythrocytes. The maximum changes were observed in the experimental subgroup of rats exposed to the combined effects of constant illumination and depriming toxicant. It was also found that the revealed positive changes in the indicators of the enzymatic link of antioxidant protection in animals of the experimental subgroups are associated with the maintenance of a sufficient concentration of reduced glutathione in red blood cells, which contributed to the maintenance of the cellular redox balance, when the conditions of the external lighting regime are violated.

Wild garlic extract reduces lipid peroxidation in terbuthylazine-treated human erythrocytes

Background: Among other negative effects, herbicides induce oxidative stress, leading to lipid peroxidation and protein oxidation. Therefore, there is a growing need to identify natural compounds with sufficient antioxidant capacity and mitigate the negative effects of herbicides without side effects. Objective: Our study aimed to examine the protective effect of the phenolic extract of wild garlic (WG) leaves on terbuthylazine-treated erythrocytes. Material and methods: In human erythrocytes treated with the herbicide terbuthylazine (4.5 mg/L) alone and a combination of terbuthylazine and WG extract, we measured malondialdehyde (MDA) and haemoglobin (Hb) concentrations and the antioxidant activities of CuZn superoxide dismutase (SOD1; EC 1.15.1.1) and catalase (CAT; EC 1.11.1.6) in vitro. Results: In comparison with terbuthylazine, WG extract reduced the concentrations of MDA and Hb from 59.69 to 43.45 nmol/gHb (27%, p < 0.001) and 165.08 to 128.64 g/L (22%, p < 0.05), respectively. Catalase activity was induced for samples treated with both WG extract and terbuthylazine compared with terbuthylazine alone (p < 0.05). Conclusions: The results demonstrated that WG may reduce the toxicity of terbuthylazine, and the erythrocyte membrane may be the primary site of phenolic action. Therefore, the lipid peroxidation intensity could be a biomarker of oxidative damage caused by terbuthylazine and the protective effect of WG.

UHPLC-ESI-OT-MS Phenolics Profiling, Free Radical Scavenging, Antibacterial and Nematicidal Activities of "Yellow-Brown Resins" from Larrea spp.

This research was designed to investigate the metabolite profiling, phenolics and flavonoids content and the potential antioxidant, antibacterial and nematicidal activities of “yellow-brown resins” from Larrea divaricata Cav (LdRe) and L. nitida Cav (LnRe). Metabolite profiling was obtained using an ultrahigh resolution liquid chromatography orbitrap MS analysis (UHPLC-ESI-OT-MS). The antioxidant properties were screened by four methods: 2,2-diphenyl-1-picrylhydrazyl assay (DPPH), trolox equivalent antioxidant activity assay (TEAC), ferric-reducing antioxidant power assay (FRAP) and lipid peroxidation in erythrocytes (LP). The antibacterial activity was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. In addition, the potential combinatory effect was analyzed with the fractional inhibitory concentration index (FICI) values using the checkerboard design. The nematicidal activity was carried out according to a standardized protocol. LdRe and LnRe showed a strong capture of the DPPH radical withvalues around 8.4 µg resin/mL; FRAP (1.69–1.94 mgTE/ g resin), TEAC (1.08–1.09 mgTE/g resin) and LP (81–82% at 100 µg of resin/mL) assays. A strong antimicrobial activity was displayed by both resins against methicillin-sensitive Staphylococcus aureus ATCC 25923(MSSA) and methicillin-resistant S. aureus ATCC 43300(MRSA) (MICs = 16–32 µg resin/mL). Additionally, the combination of LdRe or LnRe with the antibiotic cefotaxime showed an indifferent effect (FICI values = 1–1.25), however, this combinationcould be a potential strategy to reduce the drug doses, and in this way can be a potential alternative to reduce bacterial resistance. On the other hand, the resins showed a scarce nematicidal potential toward J2 Meloidogyne incognita; an important nematode infecting horticultural crops. Phenolics compounds were identified by UHPLC-PDA-OT-MS analysis, updating the knowledge on the chemical profile of these species. These results, together with the high content of quantified phenolics and flavonoids, allow the phenolics-enriched resins of these two Larrea species to be considered as a promising sustainable source of compounds of pharmacological interest.

In-vitro Anti-lipid Peroxidation and Other Antioxidant Potentials of Gongronema latifolium Leaf Extract

Gongronema latifolium is a herbaceous plant consumed as a traditional folk medicine. The aim of this work is to evaluate the anti-lipid peroxidation activity and other antioxidant effects of the plant leaf extract of Gongronema latifolium using various in vitro models. Lipid peroxidation was first induced in egg yolk and bovine liver homogenate using the ascorbate-ferrous system and incubated with the plant extract at different concentrations. In another experiment, hydrogen peroxide was used to induce erythrocyte hemolysis and lipid peroxidation and those erythrocytes were incubated with the extract. Finally the potential ferrous reducing ability, hydroxyl radical and hydrogen peroxide scavenging activities of the plant extract were also analyzed. It revealed that the leaf extract significantly reduced chemically-induced lipid peroxidation in both homogenates when compared to quercetin. The extract also reduced both hydrogen peroxide-induced hemolysis and lipid peroxidation in erythrocytes. The extract also possessed significant abilities to reduce ferric ions, scavenge both hydroxyl radicals and hydrogen peroxide. In most cases, the responses were concentration-dependent (p &lt; 0.05). The findings are ascribed to the important phytochemicals which are antioxidant in nature hence the plant could be exploited both pharmacologically and neutraceutically.

Assessment of the Inherent in-vitro Antioxidant Potential of Commelina benghalensis Leaf Extract

Commelina benghalensis is a troublesome but exotic weed native to the African and Asian subregions used traditionally for the treatment and management of various disorders. The aim of this study was to investigate the potential antioxidant activity of the methanolic leaf extract of Commelina benghalensis using various in vitro models. This was done by investigating the ability of the extract to scavenge hydrogen peroxide and hydroxyl radical. Other activities assessed were the reducing ability, ability to inhibit erythrocyte damage and reduce ferrous-ascorbate induced lipid peroxidation on bovine liver and egg yolk homogenates. The results revealed that the plant extract possessed significant hydrogen peroxide and hydroxyl radical scavenging abilities. The extract also possessed significant ability to reduce ferric ions and molybdate VI. The methanolic extract also significantly inhibited hydrogen peroxide-induced erythrocyte hemolysis and lipid peroxidation. Lipid peroxidation in bovine liver and egg yolk homogenates induced by the ferrous-ascorbate system was also reduced by the extract. In many instances, the effect of the extract was concentration-dependent. (p &lt; 0.05). This antioxidant activity of the extract is ascribed to the phytochemicals which probably acted in synergy thus the Commelina benghalensis leaves could be exploited both nutraceutically and pharmacologically.

Association between Vitamin D Supplements, Oxidative Stress Biomarkers, and Hyperbaric Therapy in Patients with Sudden Sensorineural Hearing Loss.

The effect of vitamin D supplementation to patients with sudden sensorineural hearing loss (SSNHL), treated with hyperbaric oxygen (HBO) therapy, on the markers of the oxidant-antioxidant equilibrium was investigated. Patients were divided into two groups: those who did and did not receive vitamin D (cholecalciferol at 4000 IU/24 h). Concentrations of the following compounds, thiobarbituric acid reactive substances (TBARS), malondialdehyde (MDA), conjugated dienes (CD) in plasma and erythrocytes and activities of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) in erythrocytes, were determined. Haemoglobin (HGB) and haematocrit (HCT) were measured. Blood for analyses was collected from the basilic vein at three time points: before the first HBO procedure, up to 5 min after the first procedure, and after 14 procedures. No statistically significant differences in parameters tested were found between patients who did and did not receive vitamin D. In patients without supplementation, an increase of 53.2% (P ≤ 0.05) in erythrocyte TBARS was observed after the first HBO treatment. In patients receiving vitamin D, a reduction of 27.6% (P ≤ 0.05) was observed in erythrocyte MDA after 14 HBO treatments vs. that after the first treatment. In both groups, a decrease of 33.3% in plasma CD was observed after 14 treatments vs. that after the first treatment (P ≤ 0.05 and P ≤ 0.01, respectively). No statistically significant changes were observed in the erythrocyte SOD, GPx, and CAT activities and in HCT. A reduction of HGB concentration of 10.9% (P ≤ 0.05) was demonstrated in nonsupplemented patients after 14 treatments compared with baseline. The results confirm that the effect of HBO therapy on oxidative stress markers is inconclusive and complex. Repeated HBO procedures can induce adaptive changes which protect against disruption of the oxidant-antioxidant equilibrium. It is possible that vitamin D supplementation inhibits the process of lipid peroxidation in erythrocytes.

Study of changes in erythrocyte lipid peroxidation and antioxidant potential during storage of blood

Study of changes in erythrocyte lipid peroxidation and antioxidant potential during storage of blood

Viper toxins affect membrane characteristics of human erythrocytes

Elucidating electrokinetic stability by which surface charges regulate toxins interaction with erythrocytes is crucial for understanding the cell functionality. Electrokinetic properties of human erythrocytes upon treatment of Vipoxin, phospholipase A2 (PLA2) and Vipoxin acidic component (VAC), isolated from Vipera ammodytes meridionalis venom were studied using particle microelectrophoresis. PLA2 and Vipoxin treatments alter the osmotic fragility of erythrocyte membranes. The increased stability of cells upon viper toxins is presented by the increased zeta potential of erythrocytes before sedimentation of cells during electric field applied preventing the aggregation of cells. Lipid peroxidation of low dose toxin-treated erythrocytes shows reduced LP products compared to untreated cells. The apparent proton efflux and conductivity assays are performed and the effectiveness PLA2 > Vipoxin>VAC is discussed. The reported results open perspectives to a further investigation of the electrokinetic properties of the membrane after viper toxins treatment to shed light on the molecular mechanisms driving the mechanisms of inflammation and neurodegenerative diseases

Biological Effects of Scattered Versus Scanned Proton Beams on Normal Tissues in Total Body Irradiated Mice: Survival, Genotoxicity, Oxidative Stress and Inflammation.

Side effects of proton therapy are poorly studied. Moreover, the differences in the method of dose delivery on normal tissues are not taken into account when proton beams are scanned instead of being scattered. We proposed here to study the effects of both modalities of proton beam delivery on blood; skin; lung and heart in a murine model. In that purpose; C57BL/6 mice were total body irradiated by 190.6 MeV proton beams either by Double Scattering (DS) or by Pencil Beam Scanning (PBS) in the plateau phase before the Bragg Peak. Mouse survival was evaluated. Blood and organs were removed three months after irradiation. Biomarkers of genotoxicity; oxidative stress and inflammation were measured. Proton irradiation was shown to increase lymphocyte micronucleus frequency; lung superoxide dismutase activity; erythrocyte and skin glutathione peroxidase activity; erythrocyte catalase activity; lung; heart and skin oxidized glutathione level; erythrocyte and lung lipid peroxidation and erythrocyte protein carbonylation even 3 months post-irradiation. When comparing both methods of proton beam delivery; mouse survival was not different. However, PBS significantly increased lymphocyte micronucleus frequency; erythrocyte glutathione peroxidase activity and heart oxidized glutathione level compared to DS. These results point out the necessity to take into account the way of delivering dose in PT as it could influence late side effects.

Polysaccharide from Lycium arabicum: Structural Features, in Vitro Antioxidant Activities and Protective Effect against Oxidative Damage in Human Erythrocytes.

In this research work, a water-soluble polysaccharide (LAP) isolated from the fruits of Lycium arabicum was investigated. LAP contains carbohydrates (82.45±1.23 %), protein (1.56±0.21 %), and uronic acids (3.56±0.34 %). The analysis of the monosaccharide composition revealed the presence of rhamnose, arabinose, galactose, glucose and mannose in a molar ratio of 4.7 : 1.5 : 1 : 8.7 : 16.4 : 5.6. The extracted polysaccharide (PS) was considered as heterogeneous and highly branched by interpreting its GC/MS, FT-IR and NMR data. Crystallinity of LAP was inferred from its X-ray diffractometry (XRD) and Scanning Electron Microscopy (SEM) analysis. LAP exhibited an interesting stability at high temperatures (∼254 °C) and in a wide range of pH (3-9) deduced, respectively, from its DSC and zeta potential analysis. LAP displayed a strong antioxidant activity at low concentrations evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH)-radical scavenging, ferric reducing activity power (FRAP), free radical scavenging ability, superoxide radical-scavenging and hydroxyl radical-scavenging abilities. Inhibition of erythrocyte hemolysis and lipid peroxidation was also assessed. In 5 h, LAP treatment allowed the protection of the damaged erythrocytes caused by AAPH (2,2-azobis(2-amidinopropane) dihydrochloride), to reduce the level of malondialdehyde (MDA) as well as to increase the reduced glutathione (GSH) level.

Flavonoids modulate liposomal membrane structure, regulate mitochondrial membrane permeability and prevent erythrocyte oxidative damage

In the present work, we investigated the interaction of flavonoids (quercetin, naringenin and catechin) with cellular and artificial membranes. The flavonoids considerably inhibited membrane lipid peroxidation in rat erythrocytes treated with tert-butyl hydroperoxide (700 μM), and the IC50 values for prevention of this process were equal to 9.7 ± 0.8 μM, 8.8 ± 0.7 μM, and 37.8 ± 4.4 μM in the case of quercetin, catechin and naringenin, respectively, and slightly decreased glutathione oxidation. In isolated rat liver mitochondria, quercetin, catechin and naringenin (10–50 μM) dose-dependently increased the sensitivity to Ca2+ ions - induced mitochondrial permeability transition. Using the probes TMA-DPH and DPH we showed that quercetin rather than catechin and naringenin strongly decreased the microfluidity of the 1,2-dimyristoyl-sn-glycero-3-phosphocholine liposomal membrane bilayer at different depths. On the contrary, using the probe Laurdan we observed that naringenin transfer the bilayer to a more ordered state, whereas quercetin dose-dependently decreased the order of lipid molecule packing and increased hydration in the region of polar head groups. The incorporation of the flavonoids, quercetin and naringenin and not catechin, into the liposomes induced an increase in the zeta potential of the membrane and enlarged the area of the bilayer as well as lowered the temperature and the enthalpy of the membrane phase transition. The effects of the flavonoids were connected with modification of membrane fluidity, packing, stability, electrokinetic properties, size and permeability, prevention of oxidative stress, which depended on the nature of the flavonoid molecule and the nature of the membrane.