Plasma antioxidant substances apparently do not influence the radiodermatitis occurrence / Substâncias antioxidantes do plasma aparentemente não influenciam a ocorrência de radiodermatite

AIMS: Radiation affects not only tumors but also healthy tissues through the increment of oxidative stress. Thus, this study aimed to evaluate the oxidative stress degree as well as non-enzymatic antioxidant defenses in the plasma of patients submitted to radiotherapy and to verify if these parameters are modified in those patients who develop radiodermatitis. METHODS: Forty-one patients submitted to radiotherapy for treatment of breast cancer were followed. From these patients, plasma samples were obtained at the beginning, in the middle and at the end of the treatment, for analysis of thiobarbituric acid reactive substances (TBARS) and ferric reducing ability of plasma (FRAP). RESULTS: No significant differences were observed in terms of TBARS and FRAP in plasma harvested from these patients at the beginning and at the middle of the treatment. There was lower incidence of grade two radiodermatitis among patients undergoing radiotherapy with hypofractionated doses. There were no differences in FRAP or TBARS among patients who developed radiodermatitis of any degree in relation to those who did not develop this side effect. No differences of FRAP or TBARS were observed between patients that presented grade two radiodermatitis regarding to the others studied. CONCLUSION: There was no clear relationship between changes in TBARS or FRAP with the occurrence or severity of radiodermatitis.

Study on Stability of Volatile Oil in Foeniculi Fructus and Screening Its Antioxidants in Accelerated Oxidation Environment / 中国实验方剂学杂志

Objective: To screen the accelerated oxidation environment with the most drastic changes in the volatile oil composition of Foeniculi Fructus, and to optimize the type and concentration of antioxidants. Method: The volatile oil of Foeniculi Fructus was extracted by steam distillation. Taking thiobarbituric acid reactive substances (TBARS) value and peroxide value (POV) as evaluation indexes, response surface method was used to investigate the effects of temperature, concentrations of ferrous ion (Fe2+) and azoamidine initiator V50 (AAPH) on volatile oil components of Foeniculi Fructus and its oxidation products. TBARS and POV were detected by ultraviolet chromatography. The oxidative environment with the most drastic changes of volatile oil composition of Foeniculi Fructus was screened. The type and concentration of antioxidants were selected by single factor experiments. The change discipline of volatile oil in Foeniculi Fructus after added different concentrations of antioxidants were analyzed by GC-MS. Result: The worst oxidizing environment for volatile oil of Foeniculi Fructus was as follows:temperature at 42.5℃,AAPH concentration of 1 g·L-1,Fe2+ concentration of 20.85 mg·L-1. Ascorbyl palmitate with concentrations of 0.2 mol·L-1 and 0.8 mol·L-1 could effectively improve the stability of volatile oil from Foeniculi Fructus. Conclusion: Under the accelerated oxidation environment, the terpenes in volatile oil from Foeniculi Fructus are significantly changed, but its stability can be improved by ascorbyl palmitate.

Cupremia y colesterolemia como factores de riesgo en pacientes con enfermedad de Alzheimer / Plasma levels of copper and cholesterol as risk factors in Alzheimer disease patients / Cupremia e colesterolemia como fatores de risco em pacientes com doença de Alzheimer

Se estudiaron 241 personas, 119 controles y 122 pacientes con enfermedad de Alzheimer (EA) subagrupados en tres categorías de acuerdo con el estadio clínico de la dolencia, con el objetivo de investigar la influencia de niveles elevados de cobre libre y colesterol plasmático como factores de riesgo para la EA. Las conclusiones obtenidas de los resultados indicaron que los pacientes expuestos a una combinación de alto colesterol y de cobre no unido a ceruloplasmina tuvieron mayor proporción de marcadores de estrés oxidativo (carbonilos proteicos, sustancias reactivas al tiobarbiturato, glutatión oxidado y descenso de antioxidantes totales en sangre), conjuntamente con un incremento de HDL-colesterol peroxidado y lipoproteína "a" que correlacionó con la gravedad de su cuadro. Lo mismo sucedió con la relación entre péptidos amiloides (1-40) y (1-42) en plasma y los valores del mini-test de estado cognitivo (MMSE). Se halló que una función de adición de efectos que cuantificó el daño por cobre libre y colesterol oxidado resultó directamente proporcional a la pérdida de desempeño cognitivo estimada por medio del MMSE. Esta función es de fácil determinación y puede considerarse un nuevo biomarcador para estudiar riesgo en poblaciones expuestas, apoyar el diagnóstico clínico, o evaluar la eficacia de estrategias terapéuticas en pacientes con EA.

Alzheimer disease (AD) patients (122) compared to control subjects (119) were studied to determine the role of chronic exposure of hypercholesterolemic plasma levels and free copper (not bound to ceruloplasmin) as biomarkers of progression for AD. Oxidative stress parameters, lipid profile, amyloid levels, and cognitive status were studied in all participants. Conclusions obtained indicated that patients exposed simultaneously to free copper and increased cholesterol levels present higher indicators of oxidative stress (protein carbonyls, thiobarbituric acid-reactive substances, decreased total antioxidant activity in plasma and elevated oxidized HDL-cholesterol). Lipoprotein "a" concentrations also correlated with the clinical progression of the disease. The ratio amyloid ß(1-40)/ß(1-42) in plasma inversely correlated with the cognitive performance estimated by the Mini-Mental State Examination Test (MMSE). A defined function that weighs the contribution of the deleterious effect produced by combined free copper and Ox-HDL-cholesterol exposure directly correlated with the loss of cognitive performance. Thus, this biomarker could be a new tool for the screening of large populations under risk, or may be a useful way to estimate the efficacy of therapeuti approaches in patients suffering AD.

Foram estudadas 241 pessoas, 119 controles e 122 pacientes com doença de Alzheimer (DA), agrupados em três categorias de acordo com o estágio clínico da doença, com o objetivo de investigar a influência de níveis elevados de cobre livre e colesterol plasmático como fatores de risco para a DA. As conclusões obtidas a partir dos resultados indicaram que os pacientes expostos a uma combinação de colesterol alto e de cobre não ligados à ceruloplasmina apresentaram maior proporção de marcadores de estresse oxidativo (carbonilos proteicos, substâncias reativas ao tiobarbiturato, glutationa oxidada e diminuição dos antioxidantes totais no sangue ), juntamente com um aumento da HDL-colesterol peroxidado e lipoproteína "a" que correlacionou com a gravidade de sua condição. O mesmo aconteceu com a relação entre os peptídeos amilóides (1-40) e (1-42) em plasma e os valores do mini-teste do estado cognitivo (MMSE). Verificou-se que uma função de adição de efeitos que quantificou o dano por cobre livre e colesterol oxidado resultou diretamente proporcional à perda de desempenho cognitivo estimada através do MMSE. Esta função é fácil de determinar e pode ser considerada um novo biomarcador para estudar o risco em populações expostas, apoiar o diagnóstico clínico ou avaliar a eficácia de estratégias terapêuticas em pacientes com DA.

Effect of Solanum surattense on mitochondrial enzymes in diabetic rats and in vitro glucose uptake activity in L6 myotubes.

Background: S. surattense is widely used in Siddha medicine for various ailments. Objective: The aim was to evaluate the impact of alcoholic leaf‑extract of S. surattense on mitochondrial enzymes in streptozotocin (STZ) induced diabetic rats and to study the in vitro muscle glucose uptake activity on L6 myotubes. Materials and Methods: The male albino Wistar rats were randomly divided into five groups of six animals each. Diabetes was induced by intraperitoneal injection of STZ (40 mg/kg body weight). After being confirmed the diabetic rats were treated with alcoholic leaf‑extract of S. surattense (100 mg/kg body weight) for 45 days. The biochemical estimations (liver mitochondrial enzymes, antioxidants, thiobarbituric acid reactive substances [TBARS]) and histopathological studies were performed. Further, the in vitro muscle glucose uptake activity in L6 myotubes and messenger RNA (mRNA) expression of glucose transporter‑4 (GLUT‑4) was performed. Results: In diabetic rats, the activities of liver mitochondrial enzymes were found to be significantly lowered. The mitochondrial TBARS level increased, whereas the activities/level of enzymatic and non‑enzymatic antioxidants decreased in diabetic rats. Administration of S. surattense to diabetic rats significantly reversed the above parameters toward normalcy. Furthermore in diabetic rats, the histopathological studies showed growth of adipose tissue and shrinkage of islets in the pancreas, liver showed fatty change with mild inflammation of portal triad, and kidney showed messangial capillary proliferation of glomeruli and fatty infiltration of tubules. Treatment with S. surattense brought back these changes to near normalcy. The extract was analyzed for in vitro muscle glucose uptake activity in L6 myotubes and mRNA expression of GLUT‑4 by semi‑quantitative reverse transcriptase‑polymerase chain reaction. One nano gram per millilitre of S. surattense leaf‑extract gave 115% glucose uptake on L6 myotubes. It also showed elevated levels of GLUT‑4 mRNA transcripts, when compared with control cells. Conclusion: These studies strongly support the anti‑diabetic nature of S. surattense.

Physiological responses of Catla catla larvae fed with Achyranthes aspera seed enriched diet and exposed to UV-B radiation.

The antioxidant and growth stimulating properties of seeds of Achyranthes aspera were evaluated on UV-B irradiated Catla catla (catla) larvae. Catla larvae (initial weight: 1.2 ± 0.01 mg) were fed with four different diets — D1, D2 and D3 containing 0.1, 0.25 and 0.5% seeds of A. aspera and D4, control diet for 35 days. The larvae were then exposed to UV-B radiation (80 µW/cm2) on every alternate day for 20 days. Survival, growth, tissue glutamic oxaloacetic transminase (GOT), tissue glutamate pyruvate transminase (GPT), thiobarbituric acid reactive substances (TBARS) and nitric oxide synthase (NOS) were studied in larvae on day-21 of irradiation. Significantly (P < 0.05) higher survival and average weight were found in D3 diet fed fish compared to the other groups. Survival rate was 8-16% higher in seed enriched diet fed groups, compared to the control one. Higher levels of GOT and GPT found in control diet fed larvae showed the degree of tissue damage due to UV-B exposure. Significantly (P < 0.05) lower level of GPT in D3 indicated the UV-B protective effect of the seed of A. Aspera (earlier, the presence of ecdysterone, essential fatty acids and amino acids, polyphenolic compounds, steroids, etc. has been reported from seed). TBARS which indicated the level of tissue lipid peroxidation were significantly (P < 0.05) higher in control group, compared to the other feeding schemes. NOS level was significantly (P < 0.05) higher in D2 and D3, compared to the D1 and control groups. In conclusion, supplementation of A. aspera seed (0.5%) improved the physiological condition (in terms of reduce lipid oxidation and better immune system) and gave bioprotection to catla larvae challenged with UV-B stress.

Study of possible clinical and laboratory predictors of alloimmunization against red blood cell antigens in cancer patients

Background: The inflammatory background of patients influences the process of alloimmunization against red blood cell antigens. Proof of this statement to clinical practice is still lacking. Objective: The aim of this study was to verify whether factors related to disease severity and inflammatory status of cancer patients can predict alloimmunization. Methods: This was a case-control study in which alloimmunized oncologic patients treated between 2009 and 2012 were compared with a non-alloimmunized control group regarding the severity of the disease (metastasis/performance status/body mass index) and C-reactive protein levels. Results: The groups did not differ significantly in terms of C-reactive protein, Eastern Cooperative Oncology Group (ECOG)/Karnofsky performance status, presence of metastasis and body mass index. Conclusion: It is not possible to predict alloimmunization in cancer patients based on severity of illness and inflammatory markers. Strategies of screening patients by phenotyping blood based on these criteria are not justified. .

Oxidative stress and antioxidant status in beta-thalassemia heterozygotes

Background: Several studies have evaluated the oxidant and antioxidant status of thalassemia patients but most focused mainly on the severe and intermediate states of the disease. Moreover, the oxidative status has not been evaluated for the different beta-thalassemia mutations. Objective: To evaluate lipid peroxidation and Trolox equivalent antioxidant capacity in relation to serum iron and ferritin in beta thalassemia resulting from two different mutations (CD39 and IVS-I-110) compared to individuals without beta-thalassemia. Methods: One hundred and thirty subjects were studied, including 49 who were heterozygous for beta-thalassemia and 81 controls. Blood samples were subjected to screening tests for hemoglobin. Allele-specific polymerase chain reaction was used to confirm mutations for beta-thalassemia, an analysis of thiobarbituric acid reactive species was used to determine lipid peroxidation, and Trolox equivalent antioxidant capacity evaluations were performed. The heterozygous beta-thalassemia group was also evaluated for serum iron and ferritin status. Results: Thiobarbituric acid reactive species (486.24 ± 119.64 ng/mL) and Trolox equivalent antioxidant capacity values (2.23 ± 0.11 mM/L) were higher in beta-thalassemia heterozygotes compared to controls (260.86 ± 92.40 ng/mL and 2.12 ± 0.10 mM/L, respectively; p-value < 0.01). Increased thiobarbituric acid reactive species values were observed in subjects with the CD39 mutation compared with those with the IVS-I-110 mutation (529.94 ± 115.60 ng/mL and 453.39 ± 121.10 ng/mL, respectively; p-value = 0.04). However, average Trolox equivalent antioxidant capacity values were similar for both mutations (2.20 ± 0.08 mM/L and 2.23 ± 0.12 mM/L, respectively; p-value = 0.39). There was no influence of serum iron and ferritin levels on thiobarbituric acid reactive species and Trolox equivalent antioxidant capacity values. Conclusion: ...

Chemopreventive potential of geraniol in 7,12-dimethylbenz(a) anthracene (DMBA) induced skin carcinogenesis in Swiss albino mice.

The present study investigated the chemopreventive potential of geraniol, an acyclic monoterpene alcohol, by monitoring the tumor incidence and analyzing the status of phase II detoxification agents, lipid peroxidation by products and antioxidants in 7,12-dimethylbenz(a)anthracene (DMBA) induced mouse skin carcinogenesis. Skin tumor was developed by painting DMBA (25 μg in 0.1 ml acetone mouse-1) in the shaved back of the mice, twice weekly for 8 weeks. We noticed 100% skin tumor formation in mice treated with DMBA alone. The status of phase II detoxification agents and antioxidants were decreased where as lipid peroxidation by products were increased in tumor bearing mice. Oral administration of geraniol at a dose of 250 mg kg-1 body weight significantly prevented the tumor formation as well as brought back the status of phase II detoxification agents, lipid peroxidation by products and antioxidants to near normal range in DMBA treated mice. Present results suggest that geraniol might have inhibited abnormal cell proliferation occurring in skin carcinogenesis by modulating the activities of phase II detoxification agents and through its free radical scavenging potential.

Os efeitos da ventilação mecânica no estresse oxidativo / The effects of mechanical ventilation on oxidative stress

OBJETIVO: A ventilação mecânica constitui um dos pilares terapêuticos da unidade de terapia intensiva, entretanto, deve-se avaliar os efeitos deletérios por ela ocasionados, logo objetivamos avaliar o estresse oxidativo de pacientes internados em unidade de terapia intensiva submetidos à ventilação mecânica invasiva. MÉTODOS: Estudo transversal onde foram incluídos 12 pacientes que estavam em ventilação mecânica invasiva. As coletas sanguíneas (3 mL) foram realizadas no primeiro e último dia em que o paciente estava submetido a ventilação mecânica invasiva e utilizou-se o plasma para avaliação das substâncias que reagem ao ácido tiobarbitúrico (TBARS) e os glóbulos vermelhos para dosagem de superóxido dismutase (SOD) e da catalase. RESULTADOS: Os pacientes apresentaram média de idade de 64,8±17,6 anos; volume corrente de 382±44,5 mL e APACHE II de 15±7. Quando comparado o TBARS inicial e ao final da ventilação houve diferença significativa (3,54±0,74 vs. 4,96±1,47; p=0,04). Em relação às enzimas antioxidantes não houve diferença. Observa-se correlação entre as variáveis PaO2/FiO2 e TBARS (r = 0,4); SOD e PaO2/FiO2 (r = 0,51) e SOD e APACHE II (r = 0,56). Quanto ao desfecho da internação, 6 pacientes foram a óbito. CONCLUSÃO: Pacientes submetidos à ventilação mecânica invasiva podem apresentar alteração do estado redox, marcado pelo aumento no TBARS e redução das enzimas antioxidantes.

OBJECTIVE: Mechanical ventilation is a mainstay of therapy in intensive care units; however, its deleterious effects need to be assessed. Therefore, we aimed to assess oxidative stress in patients admitted to an intensive care unit undergoing invasive mechanical ventilation. METHODS: This cross-sectional study included 12 invasive mechanical ventilation patients. Blood samples (3 mL) were collected on the first and last days on invasive mechanical ventilation. Thiobarbituric acid-reacting substances (TBARS) were assessed in plasma, and superoxide dismutase (SOD) and catalase (CAT) were assessed in erythrocytes. RESULTS: The mean age was 64.8 ± 17.6 years, the tidal volume (VT) 382 ± 44.5 mL, and the APACHE II score 15 ± 7. When initial and final TBARS were compared, a significant difference was identified (3.54 ± 0.74 vs. 4.96 ± 1.47, p = 0.04). Antioxidant enzymes showed no significant differences. Correlations between PaO2/FiO2 and TBARS (r = 0.4), SOD and PaO2/FiO2 (r = 0.51) and APACHE II and SOD (r = 0.56) were identified. Six patients died. CONCLUSION: Patients undergoing invasive mechanical ventilation can develop redox state changes, showing increased TBARS and reduced antioxidant enzymes.

Avaliação das concentrações de malonaldeído e nitrito em pacientes com anemia falciforme em tratamento ou não com hidroxiureia / Evaluation of the concentration of malondialdehyde and nitrite in patients with sickle cell anemia treated or not with hydroxyurea

Objective: To determine the serum levels of malondialdehyde and nitrite in patients with sickle cell anemia treated or not with hydroxyurea in outpatient?s setting. Methods: Of the 65 patients with sickle cell anemia selected for the study, 51 of them were not treated with hydroxyurea (Group 1), 14 made chronic use of hydroxyurea (Group 2) and 20 individuals had no hemoglobinopathies (Control Group). Results: The Control Group had a lower and more homogeneous concentration of malondialdehyde levels as compared to the other groups. The results of Groups 1 and 2 showed increased values of malondialdehyde levels when compared to the Control Group. Considering the values of Groups 1 and 2, there were no significant changes in the malondialdehyde levels. There was no significant difference in the serum levels of nitrite between the groups. Group 2 presented a statistically significant correlation between serum malondialdehyde levels and the clinical variables investigated. In turn, Group 1 showed correlation only with occurrence of three or more vaso-occlusive crises. There was no correlation between nitrite levels and the clinical variables. Conclusion: The results revealed that during the pathogenesis of sickle cell anemia, an increase in lipid peroxidation was observed. On the other hand, no changes in oxidative parameters were detected during treatment with hydroxyurea, probably due to the short period of treatment of the patients studied.

Objetivo: Determinar os níveis séricos de malonaldeído e de nitrito em pacientes com anemia falciforme em tratamento ou não com hidroxiureia e em acompanhamento ambulatorial. Métodos: Dos 65 pacientes com diagnóstico de anemia falciforme selecionados para o estudo, 51 não fizeram tratamento com hidroxiureia (Grupo 1) e 14 fizeram uso crônico de hidroxiureia (Grupo 2), sendo que 20 indivíduos não tinham hemoglobinopatias (Grupo Controle). Resultados: O Grupo Controle possuía menor e mais homogênea concentração dos níveis de malonaldeído em relação aos outros grupos. Os resultados do Grupo 1 e do Grupo 2 mostraram valores aumentados dos níveis de malonaldeído quando comparados ao Grupo Controle. Quando comparados os valores dos Grupos 1 e 2, não foram observadas alterações significativas nos níveis de malonaldeído. Não houve diferença significativa nos níveis séricos de nitrito entre os grupos. Verificou-se que, no Grupo 2, houve uma correlação estatisticamente significativa dos níveis séricos de malonaldeído com as variáveis clínicas investigadas. Por sua vez, o Grupo 1 mostrou correlação somente com a ocorrência de três ou mais crises vaso-oclusivas. Não se verificou nenhuma correlação nos níveis de nitrito com as variáveis clínicas. Conclusão: Os resultados revelaram que, durante o estabelecimento da patogênese da anemia falciforme, pode ser observado um aumento na peroxidação lipídica. Por outro lado, durante o tratamento com a hidroxureia, não foi detectada nenhuma alteração nos parâmetros oxidativos, provavelmente devido ao curto período de tratamento dos pacientes em estudo.

Health Effect Assessment on Volunteers Involved in the Cleanup Operation Following the Hebei Spirit Oil Spill Along the Taean Coast, Korea / 대한산업의학회지

OBJECTIVE: The objetive of this study is to assess the level of oxidative stress by the exposure to volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) in volunteers who cleaned up the crude oil spilled from the Hebei Spirit on the Coast of Taean County, Korea. METHODS: The study subjects were 46 volunteers and 37 controls from the National Institute of Environmental Research. A self-administered questionnaire was used for volunteers to examine their working environment and health effects. Urinary concentrations of hippuric acid, 1-hydroxypyrene, and 2-naphthol were measured as exposure markers for VOCs and PAHs, and urinary thiobarbituric acid reactive substances (TBARS) and 8-hydroxydeoxyguanosine (8-OHdG) levels were measured as oxidative stress markers. RESULTS: Sixty-four percent of the respondents presented a variety of symptoms, including sore eyes and throat, nausea, dizziness, headache, low back pain, and leg pain after participating in the cleanup operation. Urinary 2-naphthol and TBARS concentrations appeared higher in the volunteers. Univariate and multivariate analyses showed that urinary TBARS and 8-OHdG levels were positively correlated with urinary 2-naphthol and 1-hydroxypyrene concentrations respectively, especially among the volunteers. CONCLUSIONS: The result implies that participating in cleanup work of oil spills may have a possibility to induce oxidative damage by exposure to PAHs in crude oil.

Serum levels of brain-derived neurotrophic factor and thiobarbituric acid reactive substances in chronically medicated schizophrenic patients: a positive correlation / Níveis séricos do fator neurotrófico derivado do cérebro e dos produtos de reação com o ácido tiobarbitúrico em pacientes com esquizofrenia cronicamente medicados: correlação positiva

OBJECTIVE: The neurotrophins, antioxidant enzymes and oxidative markers have reciprocal interactions. This report verified in chronically stable medicated schizophrenic patients whether there are correlations between the serum levels of superoxide dismutase, a key enzyme in the antioxidant defense, thiobarbituric acid reactive substances, a direct index of lipid peroxidation, and brain-derived neurotrophic factor, the most widely distributed neurotrophin. METHOD: Sixty DSM-IV schizophrenic patients were included (43 males, 17 females). Mean age was 34.7 ± 10.8 years, mean age at first episode was 19.8 ± 7.9 years, and mean illness duration was 14.9 ± 8.5 years. Each subject had a blood sample collected for the determination of serum levels of brain-derived neurotrophic factor, thiobarbituric acid reactive substances and superoxide dismutase. RESULTS: Brain-derived neurotrophic factor levels showed a positive correlation with thiobarbituric acid reactive substances levels (r = 0.333, p = 0.009). Brain-derived neurotrophic factor levels were not correlated with superoxide dismutase levels (r = - 0.181, p = 0.166), and superoxide dismutase levels were not correlated with thiobarbituric acid reactive substances levels (r = 0.141, p = 0.284). CONCLUSIONS: The positive correlation between brain-derived neurotrophic factor and thiobarbituric acid reactive substances suggests the need of further investigation on intracellular interactions of neurotrophins, antioxidant enzymes and oxidative markers. In addition, this opens a venue for investigation on treatments for the prevention of neurotoxicity along the course of schizophrenia.

OBJETIVO: As neurotrofinas, enzimas antioxidantes e marcadores de oxidação têm interações. Este estudo verificou se existem correlações entre os níveis séricos de superóxido-dismutase, uma enzima chave na defesa antioxidante, os produtos de reação com o ácido tiobarbitúrico, um indicador direto de peroxidação lipídica, e o fator neurotrófico derivado do cérebro, a neurotrofina mais amplamente distribuída. MÉTODO: Sessenta pacientes portadores de Esquizofrenia pelo DSM-IV foram incluídos (43 homens, 17 mulheres), com idade média de 34,7 ± 10,8 anos, idade média no primeiro episódio de 19,8 ± 7,9 anos, e tempo médio de duração da doença de 14,9 ± 8,5 anos. Foi coletado sangue de cada sujeito para a determinação dos níveis séricos de fator neurotrófico derivado do cérebro, superóxido-dismutase e ácido tiobarbitúrico. RESULTADOS: Os níveis de fator neurotrófico derivado do cérebro se correlacionaram positivamente aos de ácido tiobarbitúrico (r = 0,333, p = 0,009) e não mostraram correlação com os de superóxido-dismutase (r = - 0,181, p = 0,166). Este último também não se correlacionou aos níveis de ácido tiobarbitúrico (r = 0,141, p = 0,284). CONCLUSÕES: A correlação positiva entre fator neurotrófico derivado do cérebro e ácido tiobarbitúrico direciona para investigações na interação intracelular entre neurotrofinas, enzimas antioxidantes e marcadores de oxidação, além de abrir perspectives para pesquisa em tratamentos para a prevenção da neurotoxicidade ao longo do curso da esquizofrenia.

Increased oxidative stress as a mechanism for decreased BDNF levels in acute manic episodes / Aumento do estresse oxidativo como um mecanismo para a diminuição dos níveis de BDNF em episódios maníacos agudos

OBJECTIVE AND METHOD: There is a growing amount of data indicating that alterations in brain-derived neurotrophic factor and increased oxidative stress may play a role in the pathophysiology of bipolar disorder. In light of recent evidence demonstrating that brain-derived neurotrophic factor levels are decreased in situations of increased oxidative stress, we have examined the correlation between serum thiobarbituric acid reactive substances, a measure of lipid peroxidation, and serum brain-derived neurotrophic factor levels in bipolar disorder patients during acute mania and in healthy controls. RESULTS: Serum thiobarbituric acid reactive substances and brain-derived neurotrophic factor levels were negatively correlated in bipolar disorder patients (r = -0.56; p = 0.001), whereas no significant correlation was observed in the control group.. CONCLUSION: These results suggest that alterations in oxidative status may be mechanistically associated with abnormal low levels of brain-derived neurotrophic factor observed in individuals with bipolar disorder.

OBJETIVO E MÉTODO: Existem crescentes evidências indicando que alterações no fator neurotrófico derivado do cérebro e aumento do estresse oxidativo podem estar envolvidos na fisiopatologia do transtorno bipolar. Considerando os achados recentes de que os níveis de fator neurotrófico derivado do cérebro estão diminuídos em situações de aumento de estresse oxidativo, nós testamos a correlação entre os níveis séricos de substâncias reativas do ácido tiobarbitúrico, um índice de peroxidação lipídica, e os níveis séricos de fator neurotrófico derivado do cérebro em pacientes portadores de transtorno bipolar durante mania aguda e em controles saudáveis. RESULTADOS: Os níveis séricos de substâncias reativas do ácido tiobarbitúrico e fator neurotrófico derivado do cérebro apresentaram uma correlação negativa em pacientes bipolares (r = -0,56; p = 0,001), enquanto não houve correlação significativa no grupo controle. CONCLUSÃO: Estes resultados sugerem que alterações de estresse oxidativo podem ser mecanisticamente associadas com níveis reduzidos de BDNF observados em indivíduos com transtorno bipolar.

Protective Effect of Kefir Grain Against Dextran Sodium Sulfate-Induced Colitis in Rats

Probiotics have emerged as a potential treatment modality for numerous gastrointestinal disorders, including IBD. However, few probiotics have undergone appropriate preclinical screening in vivo. Kefir is considered a probiotic, benefiting the host through its effects in the intestinal tract. Despite numerous studies examining the action of probiotics on the host organism, few have analyzed the effects on intestinal environment. We assessed the protective effect of kefir for three weeks before inducing colitis with 2% dextran sodium sulfate for five days. The DSS loads were similar in all DSS treatment group. The results of the experiment are as follows. Food intake and FER of experimental groups were not significantly different each other, but water consumption tended to be higher in all DSS treatment groups as compared with the normal control. And visual inspection of feces revealed mild diarrhea in rat given 2% DSS. The anti-inflammatory activity of kefir was determined by myeloperoxidase activity during the DSS treatment, and there was no significant difference in any group. The levels of thiobarbituric acid reactive substances (TBARS) as a colonic lipid peroxidation were significantly lower in the kefir intake groups than in rats treated with 2% DSS alone. The DNA % in tail and tail moment values as a DNA damage level of the blood lymphocytes in kefir intake groups tended to be lower than 2% DSS treatment alone, especially tail lengths were significantly diminished. According to the colonic histopathological assay, there were a severe inflammation of lamina propria and submucosa and mild edema in mucosa and sub mucosa in DSS alone treated group. We found a slight regenerative change in kefir treatment groups. In our experiments, this means that ulcerative colitis related to oxidative injury might be prevented by kefir as a probiotic. Further studies of the potential benefits of kefir as a probiotic in inflammatory condition are encouraged.

Melatonin prevents inflammation and oxidative stress caused by abdominopelvic and total body irradiation of rat small intestine

We investigated the day-night differences in intestinal oxidative-injury and the inflammatory response following total body (TB) or abdominopelvic (AP) irradiation, and the influence of melatonin administration on tissue injury induced by radiation. Rats (male Wistar, weighing 220-280 g) in the irradiated groups were exposed to a dose of 8 Gy to the TB or AP region in the morning (resting period - 1 h after light onset) or evening (activity span - 13 h after light onset). Vehicle or melatonin was administered immediately before, immediately after and 24 h after irradiation (10, 2.0 and 10 mg/kg, ip, respectively) to the irradiated rats. AP (P < 0.05) and TB (P < 0.05) irradiation applied in the morning caused a significant increase in thiobarbituric acid reactive substance (TBARS) levels. Melatonin treatment in the morning (P < 0.05) or evening (P < 0.05) decreased TBARS levels after TB irradiation. After AP irradiation, melatonin treatment only in the morning caused a significant decrease in TBARS levels (P < 0.05). Although we have confirmed the development of inflammation after radiotherapy by histological findings, neither AP nor TB irradiation caused any marked changes in myeloperoxidase activity in the morning or evening. Our results indicate that oxidative damage is more prominent in rats receiving TB and AP irradiation in the morning and melatonin appears to have beneficial effects on oxidative damage irrespective of the time of administration. Increased neutrophil accumulation indicates that melatonin administration exerts a protective effect on AP irradiation-induced tissue oxidative injury, especially in the morning.

Effects of Folic Acid Supplementation on Plasma Homocysteine and Thiobarbituric Acid Reactive Substances (TBARS) Levels and Liver SAM/SAH Ratio in Hyperhomocysteinaemia-induced Pregnant Rats

This study was performed to investigate effects of dietary folic acid supplementation on plasma homocysteine levels, thiobarbituric acid reactive substances (TBARS) levels and liver SAM/SAH ratio in hyperhomocysteinaemia-induced pregnant rats. Forty-two female Sprague-Dawley rats were divided three groups (C: control diet, HFD: 0.3% homocystine and 0 mg folic acid diet, HFS: 0.3 % homocystine and 8 mg/kg folic acid diet) according to homocystine and folic acid levels in the diet. They were fed experimental diets for 5 weeks prior to the mating and also during the entire period of pregnancy till gestational day 20. Dietary folic acid supplementation caused a significant decrease in plasma homocysteine levels which had been increased by a homocystine-diet, with a concomitant increase in plasma and liver folate levels. Liver TBARS levels in homocysteine-folic acid- deficient group (HFD) were higher than those in control group. Dietary folic acid supplementation increased hepatic SAM/SAH ratio in homocysteine-folic acid- supplemetantion group (HFS) when compared to the HFD (p < 0.05). These data suggest that folate depletion and elevated plasma homocysteine may promote oxidative stress in rat livers and influence the remethylation cycle of the homocysteine metabolism detrimentally. In conclusion, dietary folic acid supplementation was found to be effective for lowering plasma homocysteine levels, relieving oxidative stress, and improving the methylation status in the body.

The Effect of Different Intensities of Exerise on Plasma and Liver .ALPHA.-Tocopherol Levels and Hepatic Thiobarbituric Acid Reactive Substance Levels of Rats / 体力科学

The purpose of this study was to investigate the effects of different intensities of exercise on α-tocopherol and thiobarbituric acid reactive substance (TBARS) levels in the plasma and liver of rats. Male Wistar rats were divided into a sedentary control group and exercise groups. The exercise groups were forced to exercise by treadmill running at 30%, 60% and 80% of maximum oxygen uptake (VO<SUB>2</SUB>max) for 120 minutes. Some animals in each exercise group were sacrificed immediately and others at 6 hours after the exercise period, α-Tocopherol levels in the plasma and liver were analyzed by HPLC. Plasma α-tocopherol levels of rats sacrificed immediately after the exercise period decreased significantly in the 60% and 80%VO<SUB>2</SUB>max groups compared to controls. In all exercise groups, plasma α-tocopherol levels were significantly higher 6 hours after the exercise period compared to those sacrificed immediately after the exercise period. Liver a -tocopherol levels were also lower in all exercise groups 6 hours after the exercise period, especially in the 80% VO<SUB>2</SUB>max exercise group. There were no differences in TBARS levels between the control and exercised groups. These results indicate that acute exercise induces oxidative changes in the liver, but the liver is able to compensate by increasing the consumption and release of α-tocopherol to neutralize any damage.

Effects of Shengmai San on oxidative damage in mentally stressed mice / 中国病理生理杂志

AIM: To investigate the preventive effects of Shengmai San (SMS) on oxidative damage in mentally stressed mice.METHODS: An oxidative stress mouse model was established by moustache-removed. Protein carbonyl and thiobarbituric acid reactive substance (TBARS) formation were determined as the oxidative stress markers.RESULTS: (1)Moustache-cut was founded to significantly enhance the behavioral movements of mice, especially large movements (movement 2 and rearing). SMS pre-administration inhibited the accelerated movements. (2) Protein carbonyl was increased in brain, heart, liver and kidney. TBARS in liver and heart increased in the moustache-cut mice, but SMS pretreatment inhibited the increased protein carbonyl and TBARS.CONCLUSION: SMS has the preventive effects on oxidative damage induced by emotional stress.