Effects of elderflower extract enriched with polyphenols on antioxidant defense of salmon leukocytes

BACKGROUND: In fish farming, the plant extracts containing antioxidant compounds have been added to the diet for enhancing pathogen resistance. In vitro studies evaluating the antioxidant effect of herbal extracts on fish cell models have focused on ROS production and the respiratory burst mechanism. However, the effects on enzymatic antioxidant defense on salmon leukocytes have not been evaluated. This study aims to evaluate the enzymatic antioxidant defense and ROS-induced cell damage in Salmon Head Kidney-1 (SHK-1) cell line exposed to polyphenol-enriched extract from Sambucus nigra flowers. RESULTS: Firstly, the Total Reactive Antioxidant Power (TRAP) assay of elderflower polyphenol (EP) was evaluated, showing 459 and 489 times more active than gallic acid and butyl hydroxy toluene (BHT), respectively. The toxic effect of EP on salmon cells was not significant at concentrations below 120 mg/ mL and no hemolysis activity was observed between 20 and 400 mg/mL. The treatment of SHK-1 cell line with EP decreased both the lipid peroxidation and protein oxidation induced by H2O2, which could be associated with decreasing oxidative stress in the SHK-1 cells since the GSH/GSSG ratio increased when only EP was added. CONCLUSIONS: These results suggest that plant extracts enriched with polyphenols could improve the enzymatic antioxidant defense of salmon leukocytes and protect the cells against ROS-induced cell damage

Antioxidant potential of Carica papaya Linn (Caricaceae) leaf extract in mice with cyclophosphamide induced oxidative stress / Potencial antioxidante do extrato de folhas de Carica papaya Linn (Caricaceae) em camundongos com estresse oxidativo induzido por ciclofosfamida

AIMS: This study aimed to investigate the effects of crude extract of Carica papaya leaves on oxidative stress in mice induced by cyclophosphamide, as well as phytochemical profile characterization of this extract. METHODS: The male Swiss mice received 15 days of treatment with the extract (500 mg kg-1, via gavage) and intraperitoneal injection of cyclophosphamide (75 mg kg-1) or saline (0.9%) on the 15th day. After 24 h the last treatment, the animals were anesthetized for blood withdrawal, sacrificed and removal of the organs for analyses (liver, kidney and heart). In the biochemical tests were determined: hematological parameters in blood, aminotransferases, alkaline phosphatase, glucose and total cholesterol dosages in plasma, enzymatic and non-enzymatic antioxidants and lipid damage marker were evaluated in different tissues, besides genotoxic and histopathological analyzes. RESULTS: In the extract of Carica papaya leaves, the flavonoids quercetin-3ß-D-glucoside and rutin were identified, besides present positive results for alkaloids, saponins and tannins. This extract increased the activity of glutathione-S-transferase and catalase enzymes in the liver and reduced the levels of reduced glutathione in the kidneys and hematocrit levels, red cell count, and hemoglobin. It promoted the decrease of the reactive species of thiobarbituric acid (TBARS) in the kidneys and the activity of enzyme aspartate aminotransferase in the plasma and was antimutagenic in the micronucleus test. CONCLUSIONS: The study showed that extract of Carica papaya was beneficial against oxidative events and prevented DNA damage. The extract also showed hepatotoxicity, therefore prolonged infusion of papaya leaves is not advisable.

OBJETIVOS: O objetivo deste estudo foi investigar os efeitos do extrato bruto de folhas de Carica papaya sobre o estresse oxidativo em camundongos induzidos pela ciclofosfamida, bem como a caracterização do perfil fitoquímico deste extrato. MÉTODOS: Os camundongos Swiss machos receberam 15 dias de tratamento com o extrato (500 mg kg-1, via gavagem) e injeção intraperitoneal de ciclofos-famida (75 mg kg-1) ou salina (0,9%) no 15º dia. Após 24 h do último tratamento, os animais foram anestesiados para retirada do sangue, sacrificados e retirada dos órgãos para análises (fígado, rim e coração). Nos testes bioquímicos foram determinados: parâmetros hematológicos em sangue, aminotransferases, fosfatase alcalina, dosagens de glicose e colesterol total no plasma, antioxidantes enzimáticos e não enzimáticos e marcador de dano lipídico foram avaliados em diferentes tecidos, além de análises genotóxicas e histopatológicas. RESULTADOS: No extrato de folhas de Carica papaya foram identificados os flavonoides quercetina-3ß-D-glicosídeo e rutina, além de resultados positivos para alcaloides, saponinas e taninos. Este extrato aumentou a atividade das enzimas glutationa-S-transferase e catalase no fígado e diminuiu os níveis de glutationa reduzida nos rins, a concentração do hematócrito, a contagem dos glóbulos vermelhos e a hemoglobina. Promoveu a diminuição das espécies reativas de ácido tiobarbitúrico (TBARS) nos rins, a atividade da enzima aspartato aminotransferase no plasma e foi antimuta-gênico no teste do micronúcleo. CONCLUSÕES: O estudo mostrou que o extrato de Carica papaya foi benéfico contra eventos oxidativos e preveniu danos no DNA. O extrato também mostrou hepatotoxicidade, portanto, a infusão prolongada de folhas de mamão não é aconselhável.

Oxidative stress and antioxidant defense in detoxification systems of snake venom-induced toxicity

Snakebites remain a major life-threatening event worldwide. It is still difficult to make a positive identification of snake species by clinicians in both Western medicine and Chinese medicine. The main reason for this is a shortage of diagnostic biomarkers and lack of knowledge about pathways of venom-induced toxicity. In traditional Chinese medicine, snakebites are considered to be treated with wind, fire, and wind-fire toxin, but additional studies are required. Methods: Cases of snakebite seen at the Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine were grouped as follows: fire toxin - including four cases of bites by Agkistrodon acutus and three bites by Trimeresurus stejnegeri - and wind-fire toxin - four cases of bites by vipers and three bites by cobras. Serum protein quantification was performed using LC-MS/MS. Differential abundance proteins (DAPs) were identified from comparison of snakebites of each snake species and healthy controls. The protein interaction network was constructed using STITCH database. Results: Principal component analysis and hierarchical clustering of 474 unique proteins exhibited protein expression profiles of wind-fire toxins that are distinct from that of fire toxins. Ninety-three DAPs were identified in each snakebite subgroup as compared with healthy control, of which 38 proteins were found to have significantly different expression levels and 55 proteins displayed no expression in one subgroup, by subgroup comparison. GO analysis revealed that the DAPs participated in bicarbonate/oxygen transport and hydrogen peroxide catabolic process, and affected carbon-oxygen lyase activity and heme binding. Thirty DAPs directly or indirectly acted on hydrogen peroxide in the interaction network of proteins and drug compounds. The network was clustered into four groups: lipid metabolism and transport; IGF-mediated growth; oxygen transport; and innate immunity. Conclusions: Our results show that the pathways of snake venom-induced toxicity may form a protein network of antioxidant defense by regulating oxidative stress through interaction with hydrogen peroxide.(AU)

Research progress in oxidative stress induced by antibiotics in bacteria / 中华微生物学和免疫学杂志

Antibiotics can not only combine with specific targets, but also induce a cascade of re-active oxygen species ( ROS) in bacteria. Antioxidant defense system plays an important role in scavenging ROS and repairing injury against oxidative stress. However, the mechanism of ROS accumulation in bacteria and the action of ROS are very complicated. Therefore, this paper reviewed the mechanisms of bacterial re-sponding to oxidative stress in the existence of antibiotics. In addition, we analyzed the main problems lying in the current study and the issues needing further consideration.

Effects of Exercise Induced Autophagy on Antioxidant Defense Function of Skeletal Muscles in Mice / 中国运动医学杂志

Objective To explore whether a single bout of exhaustive exercise can activate autophagy in mice skeletal muscles and to investigate the effect and possible mechanisms of exercise-induced autophagy on antioxidant defense function in vivo.Methods Thirty healthy 4-week-old male C57BL/6 mice were randomly divided into a control group(n=6) and an exercise group(n=24).The latter was subjected to a single bout of exhaustive treadmill exercise.Gastrocnemius muscles of 6 mice on both sides were then isolated right after,as well as 6h,12h and 24h after the running.The manganese super oxide dismutase(MnSOD),total superoxide dismutase(T-SOD) and Copper-Zinc superoxide dismutase (CuznSOD) activities were determined using the xanthine oxidase method and the content of the total anti-oxygen capability(T-AOC) using the colorimetric method.The expression of Beclin1,P62 and Bcl2 mRNAs,as well as their proteins were determined using the fluorescent quantitative PCR and Western blotting.Results The expression of Beclin1 mRNA in gastrocnemius muscles of the exercise group increased more significantly than that of the control group right after the exercise,as well as 6 hours later(P＜0.01).P62 mRNA expression also increased significantly(P＜0.01) 24h after the exercise.In contrast,the expression of P62 protein at 0h,12h and 24h after the exercise decreased more significantly(P＜0.05 or P＜0.01) than that of the control group.Similarly,the expression of Bcl2 protein at 0h,6h and 12h increased significantly(P＜0.05 or P＜0.01).The MnSOD and CuznSOD activity increased significantly right after the exercise(P＜0.05).The T-SOD activity decreased significantly(P＜ 0.01) 6h after the exercise.T-AOC content increased significantly 6h,12h and 24h after the exercise (P＜0.05 or P＜0.01).The P62 protein expression was negatively correlated with T-AOC content.Conclusion The single bout of exhaustive treadmill exercise can activate the expression of such autophagyrelated factors as Beclin1 mRNA and P62 protein and increase the autophagy to a certain extent to maintain antioxidant defensive function of the skeletal muscle.

Evaluation of the Redox State of Wistar Rats Submitted to High-Fat Diet Supplemented With Infusion of Ilex paraguariensis

ABSTRACT This study aimed to evaluate the effect of Ilex paraguariensis infusion on redox state of Wistar rats submitted to high-fat and standard diet. Glutathione determination and lipid peroxidation in the hippocampus tissues and liver was performed, as well as the analysis of gene expression of superoxide dismutase, catalase and glutathione peroxidase by real-time polymerase chain reaction. The results from hippocampus showed that the groups fed with standard diet exhibited significant reduction of lipid peroxidation when supplemented with Ilex paraguariensis. The analysis from glutathione determination in the hippocampus showed a significant increase in glutathione activity in the group treated with high-fat diet and Ilex paraguariensis. In the liver, results showed no significant difference in both glutatione and lipid peroxidation analisys. Gene expression of superoxide dismutase, catalase and glutathione peroxidase showed that there was significant difference in the groups treated with high-fat diet and Ilex paraguariensis. In summary, the Ilex paraguariensis showed substantial potential for antioxidant activities.

Brain Region Specificity of Mitochondrial Biogenesis and Bioenergetics Response to Nrf2 Knockdown: A Comparison Among Hippocampus, Prefrontal Cortex and Amygdala of Male Rat Brain

ABSTRACT Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has been identified as the well-known coordinator of intracellular antioxidant defense system. Herein, we aimed to evaluate the effects of Nrf2 silencing on mitochondrial biogenesis markers peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), nuclear respiratory factor-1(NRF-1), mitochondrial transcription factor A (TFAM) and cytochrome c as well activities of two enzymes citrate synthase (CS) and malate dehydrogenase (MDH) in three brain regions hippocampus, amygdala, and prefrontal cortex of male Wistar rats. Small interfering RNA (siRNA) targeting Nrf2 was injected in dorsal third ventricle. Next, western blot analysis and biochemical assays were used to evaluation of protein level of mitochondrial biogenesis factors and CS and MDH enzymes activity, respectively. Based on findings, whilst Nrf2-silencing led to notably reduction in protein level of mitochondrial biogenesis upstream PGC-1α in three brain regions compared to the control rats, the level of NRF-1, TFAM and cytochrome c remained unchanged. Furthermore, although Nrf2 silencing increased CS activity, activity of MDH significantly decreased in hippocampus and prefrontal cortex areas. Interestingly, CS and MDH activities in amygdala did not change after Nrf2 knockdown. In conclusion, the present findings highlighted complexity of interaction of Nrf2 and mitochondrial functions in a brain region-specific manner. However, by outlining the exact interaction between Nrf2 and mitochondria, it would be possible to find a new therapeutic strategies for neurological disorders related to oxidative stress.

Selenium supplementation for the preterm Indian neonate.

Deficient antioxidant defenses in preterm infants have been implicated in diseases such as bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, periventricular leukomalacia, and intraventricular hemorrhage. The antioxidant properties of selenium make it important in the nutrition of very low-birth weight (VLBW) infants. Selenium is a component of glutathione peroxidase (GPX), an enzyme that prevents the production of free radicals. Preterm infants have low selenium stores and require supplementation by parenteral and enteral routes. This communiquι reviews the beneficial role that selenium supplementation might play in improving neonatal outcomes.

Agmatine protection against chlorpromazine-induced forebrain cortex injury in rats

This study was conducted to investigate whether agmatine (AGM) provides protection against oxidative stress induced by treatment with chlorpromazine (CPZ) in Wistar rats. In addition, the role of reactive oxygen species and efficiency of antioxidant protection in the brain homogenates of forebrain cortexes prepared 48 h after treatment were investigated. Chlorpromazine was applied intraperitoneally (i.p.) in single dose of 38.7 mg/kg body weight (BW) The second group was treated with both CPZ and AGM (75 mg/kg BW). The control group was treated with 0.9% saline solution in the same manner. All tested compounds were administered i.p. in a single dose. Rats were sacrificed by decapitation 48 h after treatment Treatment with AGM significantly attenuated the oxidative stress parameters and restored antioxidant capacity in the forebrain cortex. The data indicated that i.p. administered AGM exerted antioxidant action in CPZ-treated animals. Moreover, reactive astrocytes and microglia may contribute to secondary nerve-cell damage and participate in the balance of destructive vs. protective actions involved in the pathogenesis after poisoning.

Comparative evaluation of serum superoxide dismutase and glutathione levels in periodontally diseased patients: An interventional study.

Background: Periodontal disease is an immune-inflammatory disease characterized by connective tissue breakdown, loss of attachment, and alveolar bone resorption. Under normal physiological conditions, a dynamic equilibrium is maintained between the reactive oxygen species (ROS) and antioxidant defense capacity. Oxidative stress occurs when this equilibrium shifts in favor of ROS. Oxidative stress is thought to play a causative role in the pathogenesis of periodontal diseases. Aim: The present study was designed to estimate and compare the superoxide dismutase (SOD) and glutathione (GSH) levels in the serum of periodontitis, gingivitis, and healthy individuals before and after nonsurgical periodontal therapy. Materials and Methods: The present study was conducted in the Department of Periodontics, A. B. Shetty Memorial Institute of Dental Sciences, Deralakatte, Mangalore. The study was designed as a single blinded interventional study comprising 75 subjects, inclusive of both sexes and divided into three groups of 25 patients each. Patients were categorized into chronic periodontitis, gingivitis, and healthy. The severity of inflammation was assessed using gingival index and pocket probing depth. Biochemical analysis was done to estimate the SOD and GSH levels before and after nonsurgical periodontal therapy. Results obtained were then statistically analyzed using ANOVA test and paired t-test. Results: The results showed a higher level of serum SOD and GSH in the healthy group compared to the other groups. The difference was found to be statistically significant (P < 0.0001). The post-treatment levels of SOD were statistically higher than the pre-treatment levels in periodontitis and gingivitis group.

Bark Extract of Bathysa cuspidata in the Treatment of Liver Injury Induced by Carbon Tetrachloride in Rats

The aim of this study was to investigate the effect of bark extract Bathysa cuspidata (BCE) in the reconstitution of hepatic parenchyma and stroma after dysfunction induced by the CCl4. Liver lesions were induced by intraperitoneal administration of CCl4 (1 mL/kg) every 48 h for 12 days. The animals were treated with B. cuspidata extract (BCE) administered by gavage for another 12 days. Forty-nine rats were randomized into seven treatment groups with seven animals receiving CCl4, BCE (200, or 400 mg/kg) and the vehicle DMSO alone, or in different combinations. The extract alone showed no evidence of hepatic toxicity. In general, rats acutely exposed to CCl4 without the treatment with BCE presented high ALT and AST serum levels and high tissue content of lipid hydroperoxides, malondialdehyde, and lipid droplets. BCE administration, especially at 400 mg/kg attenuated significantly all these parameters. Furthermore, the antioxidant activities of the enzymes superoxide dismutase and catalase were significantly increased in the groups receiving this extract. These results showed that the extract of B. cuspidata stem bark stimulated the antioxidant defense system and reduced the morphological and functional liver damage in Wistar rats previously exposed to CCl4.

Protective effect of -tocopherol against hematotoxicity, hepatotoxicity and nephrotoxicity induced by nickel sulfate in male albino rats.

Among the chemical hazards, heavy metal like nickel (Ni) is considered to be a serious one. It induces severe liver and kidney damage by altering several marker enzymes and ascorbate-cholesterol metabolism. The objective of the study was to investigate the possible protective role of α-tocopherol on NiSO4 (Ni II) exposed alteration of hematological parameters, markers of liver and kidney functions, hepatic and renal antioxidant defense system in male albino rats. We have studied the effects of α-tocopherol supplementation on nickel sulfate induced alteration of body weight, hematology, liver and kidney toxicity markers (SGOT, SGPT, total protein, urea, creatinine) and hepatic and renal antioxidant defense system of male albino rats. Nickel toxicity results in decreased body weight gain and relative liver and kidney weight. Nickel treatment also resulted in alteration of hematological parameters along with increased liver and kidney toxicity markers. Nickel sulfate administration significantly increased the level of lipid peroxides and decreased antioxidant enzyme activities in hepatic and renal tissue. Simultaneous treatment with á-tocopherol exhibited a possible protective role on the toxic effect of nickel on body and organ weights, hematological parameters, SGPT activity and improved tissue antioxidant defense system. α-tocopherol, may partially prevent nickel induced alteration of hematological and biochemical parameters as well as have amelioratic effects on nickel induced alteration of antioxidant status of liver and kidney.

Selenium Priming Selectively Ameliorates Weed – Induced Phytotoxicity by Modulating Antioxidant Defense Components in Lentil (Lens culinaris Medik.) and Grass Pea (Lathyrus sativus L.).

Aims: Present investigation was performed to assess the phytotoxic effect of weed, Ageratum conyzoides L. on two pulses, lentil (Lens culinaris Medik.) and grass pea (Lathyrus sativus L.) and the ameliorative role of selenium (Se) to counter it. Place and Duration of Study: Leaf samples of Ageratum were collected from the lentilgrowing fields of Kalyani, West Bengal, India during winter of 2011-12. The lab-based works were performed at Department of Botany, R.P.M. College, West Bengal, India throughout the period of 2012. Study Design: The study was carried out using four replicates treatment-1 in a completely randomized block design. Methodology: Ageratum leaf aqueous extract of 200 mg ml-1 (w/v) was prepared and used on the two crops in (a) nutrient media, and (b) media + Se concentrations of 10, 20 and 40 μM separately. Also, Se was added alone (no extract) in nutrient media. A control (no exogenous Se, no extract) was maintained. The experiment was performed in an environmentally controlled growing chamber and plants were grown till flowering. Different morpho-physiological parameters along with root-tip mitosis and flower bud meiosis were

Modulatory effects of Azadirachta indica leaf extract on cutaneous and hepatic biochemical status during promotion phase of DMBA/TPA-induced skin tumorigenesis in mice.

The modulation in biochemical status of skin and hepatic tissue at the time point of commencement of promotion stage of skin carcinogenesis in mice and its intervention with aqueous Azadirachta indica leaf extract (AAILE) were investigated. 7,12-Dimethylbenz(a)anthracene (DMBA, 500 nmol/100 ul of acetone) was applied topically for 2 weeks (twice weekly), followed by phorbol-12-myristate-13-acetate (TPA, 1.7 nmol/100 ul) twice weekly for 6 weeks on the depilated skin of mice and AAILE was administered orally at a dose level of 300 mg/kg body wt thrice a week for 10 weeks. DMBA/TPA treatment upregulated the phase I enzymes in skin and hepatic tissue, as revealed by the increased cytochrome P450 (CYP) and cytochrome b5 (cyt b5) levels and aryl hydrocarbon hydroxylase (AHH) activity when compared to the control group and differentially modulated the activities of phase II enzymes like glutathione-s-transferase (GST), DT-diaphorase (DTD) and uridine diphosphate glucuronosyltransferase (UDP-GT). AAILE treatment decreased the DMBA/TPA-induced increase in cutaneous CYP level and enhanced the DTD and UDP-GT activities when compared with DMBA/TPA group. In the hepatic tissue of AAILE + DMBA/TPA group, an increase in UDP-GT activity was observed when compared to DMBA/TPA group. DMBA/TPA treatment did not alter the skin lipid peroxidation (LPO) level when compared to control group, however, in the animals that received AAILE treatment along with DMBA/TPA, a significant increase in LPO was observed when compared to control group. This was associated with a decrease in cutaneous reduced glutathione (GSH) level of AAILE + DMBA/TPA group. Enhanced LPO level was observed in the hepatic tissue of DMBA/TPA and AAILE + DMBA/TPA groups when compared to control group. However, no alteration was observed in their hepatic GSH levels. The micronuclei score in hepatic tissue did not exhibit significant inter-group differences. The results of the present study suggest that apart from skin, liver may be affected during DMBA/TPA-induced skin tumorigenesis. AAILE treatment has the ability to modulate these changes potentially influencing the process of tumor formation. These findings seem to be important to carcinogenesis and its intervention with anti-cancer agents.

Some UV-bystander effects are mediated through induction of antioxidant defense in mammalian cells.

Bystander effect is the communication of signals from irradiated to unexposed neighboring cells which is often mediated through factors released from irradiated cells. We have attempted to investigate whether UV-bystander phenomenon can modulate the sensitivity of A375 cells and its mechanism. For this purpose, the conditioned medium from UVC-irradiated cells, which contained these released factors, was used to treat non-exposed cells. These cells were then subsequently treated with UVC or another genotoxicant H2O2. Cell viability was determined by Trypan blue-exclusion assay, DNA damage by flow cytometry analysis, ROS production by flow cytometry and microscopic analysis. Lipid peroxidation and antioxidant defense were assayed biochemically. Our findings revealed that exposure of non-irradiated cells to these factors induced increased in SOD and catalase activities which reverted to normal levels by 8 h. During this period, the released factors-treated cells were resistant to killing by UVC or H2O2 and induced DNA damage and lipid peroxidation were also lowered. This protection from cell killing was not present 8 h after exposure to these released factors. Our results suggested UV-bystander effect increased viability of cells through induction of antioxidant defense. This indicated UV-bystander phenomenon triggers protective response in cells.

Effect of garlic (allium sativum) on hematology and erythrocyte antioxidant defense system of albino rats exposed to heavy metals (nickel II & chromium VI).

Heavy metals are stable environmental contaminants, causing various alterations in target tissues. Garlic has some beneficial effect in preventing heavy metal induced various alteration. The objective was to investigate the possible protective role of fresh aqueous homogenate of garlic on hematology, erythrocyte antioxidant defense system in male albino rats treated with NiSO4 and K2Cr2O7. Rats were divided into six groups. Group I was untreated control. Group II was given aqueous homogenate of garlic (orally). Group III was administered with nickel sulfate (i.p). Group IV was given NiSO4 and garlic simultaneously. Group V was administered with K2Cr2O7 (i.p). Group VI were treated simultaneously with K2Cr2O7 and garlic. RBC, WBC, platelet count, PCV%, hemoglobin concentration decreased significantly and clotting time increased significantly after nickel treatment. After chromium treatment all the values decreased except clotting time. Increased malondialdehyde and glutathione level after nickel and chromium treatment was observed. Also erythrocyte superoxide dismutase, glutathione peroxidase and catalase activities significantly increased after nickel and chromium treatment. Simultaneous garlic supplementation exhibited protective role to combat nickel toxicity, whereas no such beneficial effects were observed for chromium (VI). Garlic may partially prevent nickel and chromium induced alteration but such ameliorated effects as an antioxidant is only restricted on nickel induced alteration.

Liver oxidative stress of the grey mullet Mugil cephalus presents seasonal variations in Ennore estuary

The objective of this study was to determine the liver oxidative stress status of grey mullets living in heavy-metal-rich polluted Ennore estuary compared with unpolluted Kovalam estuary. Fish were collected from both estuaries during the monsoon and summer seasons from October 2004 to September 2006. Fish liver homogenate (N = 20 per group) was prepared for evaluating oxidative stress parameters. Fish living in the polluted estuary had significantly higher lipid oxidation products, conjugated dienes (0.346 ± 0.017 vs 0.141 ± 0.012 DA233/mg protein), lipid hydroperoxides (0.752 ± 0.032 vs 0.443 ± 0.03 nmol/mg protein), and lipid peroxides (3.447 ± 0.14vs 1.456 ± 0.096 nmol MDA/mg protein) than those of the unpolluted estuary during the summer. In contrast, significantly lower levels of superoxide dismutase (20.39 ± 1.14 vs 53.63 ± 1.48 units/mg protein) and catalase (116 ± 6.87vs 153 ± 8.92 units/mg protein) were detected in the liver of fish from the polluted estuary (Ennore) compared to fish from the unpolluted estuary (Kovalam) during the summer. Variations in most of the oxidative stress parameters were observed between the summer and monsoon seasons, indicating the importance of seasonal variation for estuaries and their inhabitants.

Adaptive response: some underlying mechanisms and open questions: [review]

Organisms are affected by different DNA damaging agents naturally present in the environment or released as a result of human activity. Many defense mechanisms have evolved in organisms to minimize genotoxic damage. One of them is induced radioresistance or adaptive response. The adaptive response could be considered as a nonspecific phenomenon in which exposure to minimal stress could result in increased resistance to higher levels of the same or to other types of stress some hours later. A better understanding of the molecular mechanism underlying the adaptive response may lead to an improvement of cancer treatment, risk assessment and risk management strategies, radiation protection, e.g. of astronauts during long-term space flights. In this mini-review we discuss some open questions and the probable underlying mechanisms involved in adaptive response: the transcription of many genes and the activation of numerous signaling pathways that trigger cell defenses - DNA repair systems, induction of proteins synthesis, enhanced detoxification of free radicals and antioxidant production.

Bases metabólicas da suplementação de cisteína / Metabolic Basis of supplemental cysteine / Metabólicas Bases de cisteína suplementaria

A cisteína (Cys) é um aminoácido sulfurado produzido, endogenamente, a partir da transulfuração da homocisteína. É limitante da síntese da glutationa, principal antioxidante (peroxidase) solúvel no citosol e maior fonte sulfurada endógena. Adicionalmente, a Cys origina a taurina (Tau) com papel neurotransmissor, inativador de ácidos biliares, osmolito intracelular e agente antioxidante intrafagocitário. Apenas o fígado, pãncreas e rins formam Cys a partir da metionina (Met). Nos demais tecidos, a principal fonte de Cys é a sua concentração plasmática ou as de GSH e GSSG (desde que a célula contenha y-glutamil transpeptidase e dipeptidase). A Cys (SH) é instável e se oxida facilmente a cistina (S-S), forma predominante no plasma. As células desprovidas de redutase, como os linfócitos, não convertem a Cis (S-S) a Cys (SH) e tornam-se dependentes da Cys gerada por outras células sanguíneas ou da Cys plasmática. A Cys ativa a proliferação celular e as funções de quimiotaxia, fagocitose e citoxicidade natural (de células malignas). A deficiência de Cys está associada não apenas aos menores níveis de GSH e menor defesa antioxidante, mas também à diminuição de glutamina e consequente deficiência imunitária. Não há recomendações específicas para a Cys.A RDA para Met+Cys é de 17 mg/g...

The cysteine (Cys) is a sulfur-containing amino acid produced endogenously from the transsulfuration of homocysteine. It is limiting the synthesis of glutathione, the main antioxidant (peroxidase) soluble in the cytosol and increased endogenous sulfur source. Additionally, Cys originates taurine (Tau) with paper neurotransmitter inactivation of bile acids, intracellular osmolyte and antioxidant agent intrafagocitário. Only liver, pancreas and kidneys form Cys from methionine (Met). In other tissues, the main source of Cys is its plasma concentration or GSH and GSSG (as long as the cell containing y-glutamyl transpeptidase and dipeptidase). The Cys (SH) is unstable and easily oxidized to cystine (SS), the predominant form in plasma. Cells devoid of reductase, such as lymphocytes, do not convert to Cys (SS) to Cys (SH) and become dependent on Cys generated by other blood cells or plasma Cys. The Cys active cell proliferation and functions of chemotaxis, phagocytosis, and natural cytotoxicity (malignant cells). Cys deficiency is associated not only with lower levels of GSH and lower antioxidant defense, but also to the decrease of glutamine and subsequent immune deficiency. There are no specific recommendations for Cys.A for Met + Cys RDA is 17 mg / g...

An Analysis of Dietary Intakes and Plasma Biochemical Indices in Female College Students by Skin Types / 대한지역사회영양학회지

This study was done to investigate the nutrient intakes and plasma biochemcial indices in 68 female college students according to their skin types. Nutrient intakes were investigated by quik estimation. The plasma TG and total cholesterol levels were measured by the Spotchem sp-4410. The plasma levels of retinol and alpha-tocopherol were measured by HPLC. In addition, the activities of antioxidant defense enzymes such as plasma glutathione peroxidase(GSH-Px) and glutathione reductase(GHS-Rd) were determined. All data were statistically analyzed by SAS PC package program. The results of this study were as follows : The average age, height, weight, BMI, systolic blood pressure and diastolic blood pressure ofthe subjects were 20.9+/-1.9yr, 160.7+/-4.3cm, 53.0+/-7.1kg, 20.5+/-2.4kg/m2, 105.3+/-11.5mmHg and 70.6+/-7.7mmHg, respectively. Ten students(14.7%) had normal skin type, 19 students(27.9%) had dry skin type, 11 students(16.2%) had oily skin type, 17 students(25.0%) had acne and 11 students(16.2%) had mixed skin type. The intakes of energy and fats in oily skin group were significantly higher(p<0.05) than those of the dry skin group, but vitamin C intake in the mixed skin group was significantly higher(p<0.05) than those of the dry skin group, but vitamin C intake in the mixed skin group was significantly lower(p<0.05) than that in other skin types. The intakes of other nutrients were not significantly different among skin types. The analysis of lipids showed that the plasma total-cholesterol level of mixed skin group was significantly lower(p<0.05) than that of the oily skin group, whereas other lipid levels were not significantly different. The other parameters such as retinol, alpha-tocopherol, GSH-Px and GSH-Rd of plasma were not significantly different among skin types. Overall results indicate that dietary intake pattern may influence skin type and thereby some blood biochemical indices can be different by skin types.