Study of the potential toxicity of adrenaline to neurons, using the SH-SY5Y human cellular model

Abstract Prolonged overexposure to catecholamines causes toxicity, usually credited to continuous adrenoceptor stimulation, autoxidation, and the formation of reactive pro-oxidant species. Non-differentiated SH-SY5Y cells were used to study the possible contribution of oxidative stress in adrenaline (ADR)-induced neurotoxicity, as a model to predict the toxicity of this catecholamine to peripheral nerves. Cells were exposed to several concentrations of ADR (0.1, 0.25, 0.5 and 1mM) and two cytotoxicity assays [lactate dehydrogenase (LDH) release and 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction] were performed at several time-points (24, 48, and 96h). The cytotoxicity of ADR was concentration- and time-dependent in both assays, since the lowest concentration tested (0.1mM) also caused significant cytotoxicity at 96h. N-acetyl-cysteine (1mM), a precursor of glutathione synthesis, prevented ADR-induced toxicity elicited by 0.5mM and 0.25mM ADR following a 96-h exposure, while the antioxidant Tiron (100µM) was non-protective. In conclusion, ADR led to mitochondrial distress and ultimately cell death in non-differentiated SH-SY5Y cells, possibly because of ADR oxidation products. The involvement of such processes in the catecholamine-induced peripheral neuropathy requires further analysis.

Chemical composition and phytotoxicity of essential oils of Croton doctoris S. Moore (Euphorbiaceae) / Composição química e fitotoxicidade dos óleos essenciais de Croton doctoris S. Moore (Euphorbiaceae)

Essential oils from the stems and leaves of Croton doctoris were analyzed by gas chromatography and mass spectrometry, resulting in 22 identified compounds. The effects of these essential oils on the germination, root and shoot growth, total chlorophyll content, potential root respiration, peroxidase activity, catalase, superoxide dismutase, and mitotic index in lettuce and onion were determined. Antioxidant, antimicrobial, and cytotoxic activity were also investigated. The results revealed that the stem oil consisted of 15 compounds, of which caryophyllene oxide (24.5%) and E-caryophyllene (13.3%) were the major constituents. The leaf oil contained E-caryophyllene (39.6%) and α-humulene (13.2%) as major compounds. The oils inhibited the germination and growth of lettuce and onion seedlings and reduced chlorophyll content, root respiration, and cell division. They also caused oxidative stress, indicated by the increased activity of the evaluated antioxidant enzymes. These abnormal physiological processes contributed to the inhibition of plant growth. The most pronounced phytotoxic effects were observed in the stem oil. The cytotoxicity tests indicated that leaf oil was more active than stem oil, resulting from the presence of biologically active sesquiterpenes that inhibit the growth of cancer cells.

Os óleos essenciais do caule e da folha de Croton doctoris foram analisados por cromatografia gasosa (GC) e espectrometria de massa (GC-MS) resultando em 22 compostos identificados. Os efeitos dos óleos essenciais na germinação, crescimento de raízes e parte aérea, teor total de clorofila, respiração radicular, atividade de peroxidase, catalase e superóxido de dimetase e índice mitótico foram determinados em alface e cebola. Atividade antioxidante, antimicrobiana e citotóxica também foram investigadas. Os resultados revelaram que o óleo do caule é constituído por 15 compostos, dos quais os principais são o óxido de cariofileno (24,5%) e E-cariofileno (13,3%). O óleo foliar apresentou E-cariofileno (39,6%) seguido de α-humuleno (13,2%) como compostos majoritários. Os óleos inibiram a germinação e o crescimento das plântulas de alface e cebola e reduziram o conteúdo de clorofila, a respiração radicular e a divisão celular. Eles também causaram estresse oxidativo, indicado pelo aumento da atividade das enzimas antioxidantes avaliadas. Esses processos fisiológicos anormais contribuem para a inibição do crescimento das plantas. Os efeitos fitotóxicos mais pronunciados foram observados no óleo do caule. Nos testes de citotoxicidade observou-se que o óleo das folhas foi mais ativo, resultante da presença de sesquiterpenos biologicamente ativos que atuam inibindo o crescimento das células cancerígenas.

Chemical composition and phytotoxicity of essential oils of Croton doctoris S. Moore (Euphorbiaceae)

Abstract Essential oils from the stems and leaves of Croton doctoris were analyzed by gas chromatography and mass spectrometry, resulting in 22 identified compounds. The effects of these essential oils on the germination, root and shoot growth, total chlorophyll content, potential root respiration, peroxidase activity, catalase, superoxide dismutase, and mitotic index in lettuce and onion were determined. Antioxidant, antimicrobial, and cytotoxic activity were also investigated. The results revealed that the stem oil consisted of 15 compounds, of which caryophyllene oxide (24.5%) and E-caryophyllene (13.3%) were the major constituents. The leaf oil contained E-caryophyllene (39.6%) and -humulene (13.2%) as major compounds. The oils inhibited the germination and growth of lettuce and onion seedlings and reduced chlorophyll content, root respiration, and cell division. They also caused oxidative stress, indicated by the increased activity of the evaluated antioxidant enzymes. These abnormal physiological processes contributed to the inhibition of plant growth. The most pronounced phytotoxic effects were observed in the stem oil. The cytotoxicity tests indicated that leaf oil was more active than stem oil, resulting from the presence of biologically active sesquiterpenes that inhibit the growth of cancer cells.

Resumo Os óleos essenciais do caule e da folha de Croton doctoris foram analisados por cromatografia gasosa (GC) e espectrometria de massa (GC-MS) resultando em 22 compostos identificados. Os efeitos dos óleos essenciais na germinação, crescimento de raízes e parte aérea, teor total de clorofila, respiração radicular, atividade de peroxidase, catalase e superóxido de dimetase e índice mitótico foram determinados em alface e cebola. Atividade antioxidante, antimicrobiana e citotóxica também foram investigadas. Os resultados revelaram que o óleo do caule é constituído por 15 compostos, dos quais os principais são o óxido de cariofileno (24,5%) e E-cariofileno (13,3%). O óleo foliar apresentou E-cariofileno (39,6%) seguido de -humuleno (13,2%) como compostos majoritários. Os óleos inibiram a germinação e o crescimento das plântulas de alface e cebola e reduziram o conteúdo de clorofila, a respiração radicular e a divisão celular. Eles também causaram estresse oxidativo, indicado pelo aumento da atividade das enzimas antioxidantes avaliadas. Esses processos fisiológicos anormais contribuem para a inibição do crescimento das plantas. Os efeitos fitotóxicos mais pronunciados foram observados no óleo do caule. Nos testes de citotoxicidade observou-se que o óleo das folhas foi mais ativo, resultante da presença de sesquiterpenos biologicamente ativos que atuam inibindo o crescimento das células cancerígenas.

Chemical composition and phytotoxicity of essential oils of Croton doctoris S. Moore (Euphorbiaceae) / Composição química e fitotoxicidade dos óleos essenciais de Croton doctoris S. Moore (Euphorbiaceae)

Essential oils from the stems and leaves of Croton doctoris were analyzed by gas chromatography and mass spectrometry, resulting in 22 identified compounds. The effects of these essential oils on the germination, root and shoot growth, total chlorophyll content, potential root respiration, peroxidase activity, catalase, superoxide dismutase, and mitotic index in lettuce and onion were determined. Antioxidant, antimicrobial, and cytotoxic activity were also investigated. The results revealed that the stem oil consisted of 15 compounds, of which caryophyllene oxide (24.5%) and E-caryophyllene (13.3%) were the major constituents. The leaf oil contained E-caryophyllene (39.6%) and α-humulene (13.2%) as major compounds. The oils inhibited the germination and growth of lettuce and onion seedlings and reduced chlorophyll content, root respiration, and cell division. They also caused oxidative stress, indicated by the increased activity of the evaluated antioxidant enzymes. These abnormal physiological processes contributed to the inhibition of plant growth. The most pronounced phytotoxic effects were observed in the stem oil. The cytotoxicity tests indicated that leaf oil was more active than stem oil, resulting from the presence of biologically active sesquiterpenes that inhibit the growth of cancer cells.

Os óleos essenciais do caule e da folha de Croton doctoris foram analisados por cromatografia gasosa (GC) e espectrometria de massa (GC-MS) resultando em 22 compostos identificados. Os efeitos dos óleos essenciais na germinação, crescimento de raízes e parte aérea, teor total de clorofila, respiração radicular, atividade de peroxidase, catalase e superóxido de dimetase e índice mitótico foram determinados em alface e cebola. Atividade antioxidante, antimicrobiana e citotóxica também foram investigadas. Os resultados revelaram que o óleo do caule é constituído por 15 compostos, dos quais os principais são o óxido de cariofileno (24,5%) e E-cariofileno (13,3%). O óleo foliar apresentou E-cariofileno (39,6%) seguido de α-humuleno (13,2%) como compostos majoritários. Os óleos inibiram a germinação e o crescimento das plântulas de alface e cebola e reduziram o conteúdo de clorofila, a respiração radicular e a divisão celular. Eles também causaram estresse oxidativo, indicado pelo aumento da atividade das enzimas antioxidantes avaliadas. Esses processos fisiológicos anormais contribuem para a inibição do crescimento das plantas. Os efeitos fitotóxicos mais pronunciados foram observados no óleo do caule. Nos testes de citotoxicidade observou-se que o óleo das folhas foi mais ativo, resultante da presença de sesquiterpenos biologicamente ativos que atuam inibindo o crescimento das células cancerígenas.

Inoculation of corn seeds with Azospirillum brasilense in different temperatures / Inoculation of corn seeds with Azospirillum brasilense in different temperatures

Growth-promoting bacteria Azospirillum brasilense, used as an inoculant in corn culture, can be severely affected by the exposure temperature, with a lethal effect above 35°C, when cultivated alone under laboratory conditions. Such effects may limit the associative interaction between plant-bacteria, with reduced inoculation efficiency, resulting in a lower growth rate of the plant and an increase in oxidative stress. Thus, the objective of the research was to evaluate the efficiency of the inoculation process with A. brasilense in seeds and in the initial growth of seedlings of two corn cultivars submitted to different temperatures. Were utilized corn hybrids seed Syn 488 and Syn 505. The experimental design was completely randomized in a 2 x 4 factorial scheme (with and without inoculation of A. brasilense x 4 sowing temperatures: 20, 25, 30, and 35ºC), with four replications. The inoculation efficiency in corn seedlings submitted to different temperatures was evaluated through the following tests: germination, first count, seedling length and dry weight. In addition, responses at the biochemical level of the interaction (temperatures x inoculation) for the content of photosynthetic pigments and hydrogen peroxide (H2O2), antioxidant enzymes and lipid peroxidation were evaluated. The inoculation with A. brasilense changed the morphological and biochemical responses of corn see

Growth-promoting bacteria Azospirillum brasilense, used as an inoculant in corn culture, can be severely affected by the exposure temperature, with a lethal effect above 35°C, when cultivated alone under laboratory conditions. Such effects may limit the associative interaction between plant-bacteria, with reduced inoculation efficiency, resulting in a lower growth rate of the plant and an increase in oxidative stress. Thus, the objective of the research was to evaluate the efficiency of the inoculation process with A. brasilense in seeds and in the initial growth of seedlings of two corn cultivars submitted to different temperatures. Were utilized corn hybrids seed Syn 488 and Syn 505. The experimental design was completely randomized in a 2 x 4 factorial scheme (with and without inoculation of A. brasilense x 4 sowing temperatures: 20, 25, 30, and 35ºC), with four replications. The inoculation efficiency in corn seedlings submitted to different temperatures was evaluated through the following tests: germination, first count, seedling length and dry weight. In addition, responses at the biochemical level of the interaction (temperatures x inoculation) for the content of photosynthetic pigments and hydrogen peroxide (H2O2), antioxidant enzymes and lipid peroxidation were evaluated. The inoculation with A. brasilense changed the morphological and biochemical responses of corn see

Cryotherapy: biochemical alterations involved in reduction of damage induced by exhaustive exercise

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.

Foxo3 gene expression and oxidative status in beta-thalassemia minor subjects

ABSTRACT Background: Oxidative stress may aggravate symptoms of hemolytic anemias such as beta-thalassemia. FoxO3 activation results in resistance to oxidative stress in fibroblasts and neuronal cell cultures. Objective: The purpose of this research was to study FoxO3 gene expression and oxidative status in beta-thalassemia minor individuals. Methods: Sixty-three subjects (42 apparently healthy individuals and 21 with beta-thalassemia minor) were analyzed at the Universidad Nacional de Tucumán, Argentina, between September 2013 and June 2014. A complete blood count, hemoglobin electrophoresis in alkaline pH and hemoglobin A2 levels were quantified. Moreover, thiobarbituric acid reactive species, erythrocyte catalase activity and iron status were evaluated. Beta-thalassemia mutations were determined by real-time polymerase chain reaction. FoxO3 gene expression was investigated by real-time reverse transcription-polymerase chain reaction using mononuclear cells from peripheral blood. Results: Subjects were grouped as children (≤12 years), and adult women and men. The analysis of erythrocyte catalase activity/hemoglobin ratio revealed a significant difference (p-value <0.05) between healthy and beta-thalassemia minor adults, but no significant difference was observed in the thiobarbituric acid reactive species levels and FoxO3 gene expression (p-value >0.05). Thiobarbituric acid reactive species and the erythrocyte catalase activity/hemoglobin ratio were not significantly different on comparing the type of beta-thalassemia mutation (β0 or β+) present in carriers. Conclusions: The lack of systemic oxidative imbalance demonstrated by thiobarbituric acid reactive species is correlated to the observation of normal FoxO3 gene expression in mononuclear cells of peripheral blood. However, an imbalanced antioxidant state was shown by the erythrocyte catalase activity/hemoglobin ratio in beta-thalassemia minor carriers. It would be necessary to study FoxO3 gene expression in reticulocytes to elucidate the role of FoxO3 in this pathology.

Obesity, bariatric surgery and oxidative stress / Obesidade, cirurgia bariátrica e estresse oxidativo

Summary Introduction: Obesity refers to the accumulation of fatty tissues and it favors the occurrence of oxidative stress. Alternatives that can contribute to body weight reduction have been investigated in order to reduce the production of reactive oxygen species responsible for tissue damage. The aim of the current study was to assess whether the oxidant and antioxidant markers of obese women before and after bariatric surgery were able to reduce oxidative damage. Method: We have assessed 16 morbidly obese women five days before and 180 days after the surgery. The control group comprised 16 non-obese women. Levels of thiobarbituric acid-reactive substances, carbonylated proteins, reduced glutathione and ascorbic acid were assessed in the patients' plasma. Results: Levels of lipid peroxidation and protein carbonylation in the pre-surgical obese women were higher than those of the controls and post-surgical obese women. Levels of reduced glutathione in the pre-surgical obese women were high compared to the controls, and declined after surgery. Levels of ascorbic acid fell in the pre--surgical obese women compared to the control and post-surgical obese women. Conclusion: Body weight influences the production of reactive oxygen species. Bariatric surgery, combined with weight loss and vitamin supplementation, reduces cellular oxidation, thus reducing tissue damage.

Resumo Introdução: Na obesidade, verifica-se um acúmulo de tecido adiposo, o que favorece a ocorrência de estresse oxidativo. A fim de diminuir a produção das espécies reativas que levam a danos teciduais, buscam-se alternativas que contribuam para a redução do peso corporal. Este estudo avaliou se os marcadores oxidantes e antioxidantes de obesas antes e após cirurgia bariátrica reduziram o dano oxidativo. Método: Foram avaliadas 16 mulheres obesas mórbidas cinco dias antes e 180 dias após o procedimento cirúrgico. O grupo controle constituiu-se de 16 mulheres não obesas. Os níveis das substâncias reativas ao ácido tiobarbitúrico, das proteínas carboniladas, da glutationa reduzida e do ácido ascórbico foram avaliados no plasma dessas pacientes. Resultados: Os níveis de lipoperoxidação e da carbonilação de proteínas nas obesas pré-cirúrgicas eram mais elevados quando comparados ao controle e às obesas pós-cirúrgicas; os níveis de glutationa reduzida eram maiores nas obesas pré-cirúrgicas em comparação ao controle e diminuíram após a cirurgia; os níveis de ácido ascórbico eram menores nas obesas pré-cirúrgicas em relação ao controle e às obesas pós-cirúrgicas. Conclusão: Observou-se que a massa corporal influenciou na produção das espécies reativas. A cirurgia bariátrica, somada à perda de peso e à suplementação vitamínica, diminui a oxidação celular e, com isso, reduz os danos teciduais.

Biomarcadores inflamatórios e de estresse oxidativo em cadelas submetidas à ovário-histerectomia videoassistida ou convencional / Inflammation and oxidative stress indicators in bitches submitted to laparoscopic-assisted or conventional ovariohysterectomy

A videocirurgia é atualmente uma das principais ferramentas operatórias, com vantagens que incluem menor estresse, incisões e dor pós-operatória quando comparada aos procedimentos abertos. Objetivou-se comparar o processo inflamatório e o estresse oxidativo resultantes das técnicas de ovário-histerectomia (OVH) convencional e videoassistida, com dois portais em cadelas, por meio de hemograma, avaliação de acetilcolinesterase, butirilcolinesterase, catalase e malondialdeído séricos, imediatamente antes da operação e duas, seis, 12, 24, 48 e 72 horas após a cirurgia. Observou-se menor estresse cirúrgico nas pacientes operadas pela técnica videoassistida, e sugere-se que a técnica convencional possa implicar peroxidação lipídica, mesmo com o uso de anti-inflamatório.(AU)

Videosurgery is currently a very important surgical tool with several benefits over the open surgery, including less surgical stress, shorter incisions and less postoperative pain. The purpose of this study was to compare the inflammatory process and oxidative stress between conventional and two-port laparoscopic-assisted ovariohisterectomy (OVH) in bitches. Complete blood counting, serum acetylcholinesterase, butyrylcholinesterase, catalase and malondialdehyde were assessed on the baseline and at two, six, 12, 24, 48 and 72 hours after surgery. The patients submitted to the videoassisted technique presented lower inflammatory response. There are suggestions that the conventional technique promotes lipid peroxidation, even with the use of anti-inflammatories.(AU)

Diferencias del estado redox entre espermatozoides y plasma seminal en adultos jóvenes / Difference of redux status between spermatozoa and seminal plasma in young adults

Introducción: Las especies reactivas del oxígeno y el estrés oxidativo desempeñan un papel fundamental en la infertilidad masculina. Sin embargo, estas especies oxidantes también han sido asociadas con los procesos de capacitación de los gametos masculinos cuando son generadas a bajos niveles y de manera controlada. Actualmente los biomarcadores redox son introducidos en el diagnóstico clínico de la infertilidad masculina en el mundo, como una herramienta complementaria a los parámetros del espermiograma. Sin embargo, en Cuba, esta metodología aún no se encuentra extendida a los servicios de salud. Objetivo: El objetivo del presente trabajo fue caracterizar el estado redox de espermatozoides y el líquido seminal de sujetos aparentemente sanos, a través de la determinación de una serie de biomarcadores de estrés oxidativo. Los niveles de malonildialdehído, la actividad de las enzimas antioxidantes superóxido dismutasa y catalasa, así como los niveles de glutatión reducido, el potencial de peroxidación y la capacidad reductora fueron determinados mediante técnicas espectrofotométricas. Métodos: Se analizaron 40 muestras de semen de sujetos aparentemente sanos, las cuales fueron obtenidas mediante masturbación sin el empleo de lubricantes y con al menos tres días de abstinencia eyaculatoria. En el estudio se incluyeron sujetos de 20 a 35 años, aparentemente sanos según exámenes de laboratorio clínico y con paternidad probada. Resultados: Los resultados demostraron que existen diferencias significativas (p< 0,05) entre los marcadores evaluados en el líquido seminal con respecto al espermatozoide, lo cual sugiere la existencia de un estado redox diferenciado entre ambos compartimentos. Conclusiones: Estos hallazgos demuestran la necesidad de evaluar el nivel de estrés oxidativo tanto en las células sexuales como en el fluido que las contiene. Ello contribuirá, sin lugar a dudas, a un diagnóstico más eficaz e integral de la capacidad fértil del hombre

Background: Reactive oxygen species and oxidative stress play a fundamental role in male infertility. However, these oxidizing species have also been associated with the process of capability of male gametes when they are generated at low levels and in a controlled manner. Currently, redox biomarkers are introduced in the clinical diagnosis of male infertility in the world as a complementary tool to the spermiogram parameters. However, in Cuba, this methodology is not yet extended to health services. Objective: The objective of this study was to characterize the redox status of spermatozoa and seminal fluid of apparently healthy subjects through the identification of a number of biomarkers of oxidative stress. Methods: 40 samples of semen of apparently healthy subjects were analyzed, which were obtained by masturbation without the use of lubricants and with at least 3 days of ejaculatory abstinence. The study included subjects from 20 to 35 years of age, who were apparently healthy according to both laboratory tests and paternity test results. Results: The results showed that there are significant differences (p<0, 05) between the markers evaluated in the seminal fluid and the spermatozoon which suggests the existence of a differentiated redux status between the two compartments. Conclusions: These findings demonstrate the need to evaluate the level of oxidative stress in both sexual cells and the fluid that contains them. It will contribute, with no doubt, to a more effective and comprehensive diagnosis of man's fertility

El estrés oxidativo y los antioxidantes en la prevención del cáncer / Oxidative stress and antioxidants in cancer prevention

Introducción: el estrés oxidativo participa en la carcinogénesis; por ello, se ha considerado como estrategia para la prevención del cáncer el reforzamiento de los mecanismos celulares de defensa antioxidante. Objetivo: evaluar el papel del estrés oxidativo en el proceso de carcinogénesis, así como la utilidad y modalidades de uso de los antioxidantes en su prevención. Métodos: se realizó un trabajo de revisión bibliográfica a través de la consulta de Google, LILACS, PubMed y Hinari. Se seleccionaron artículos de revisión sobre el tema, de los últimos 5 años, así como revisiones sistemáticas y meta-análisis publicados que evalúan la utilización de suplementos de antioxidantes sintéticos en la prevención del cáncer. Desarrollo: se abordan los mecanismos carcinogénicos de las especies reactivas del oxígeno y se discuten los beneficios y amenazas del uso preventivo de suplementos de antioxidantes. También se analiza el posible impacto en el control del estrés oxidativo, la aplicación de las recomendaciones plasmadas en la Estrategia Global sobre la Dieta, la Actividad Física y la Salud de la Organización Mundial de la Salud. Finalmente, se enfatiza en los mecanismos anticarcinogénicos de diferentes fitoquímicos. Conclusiones: la promoción de hábitos saludables que evita la generación de las especies reactivas del oxígeno, unido a la ingestión de antioxidantes como componentes de la dieta, pueden conducir al equilibrio apropiado oxidantes/antioxidantes y consecuentemente a la prevención del cáncer.

Introduction: oxidative stress is involved in carcinogenesis. Consequently, the reinforcement of cellular defensive antioxidant mechanisms has been considered as strategy for cancer prevention. Objective: to evaluate the role of oxidative stress in the carcinogenesis process as well as the utility and modalities of the use of antioxidants in cancer prevention. Methods: a review was performed through the consultation of Google, LILACS, PubMed and Hinari. Review articles published in the last five years, systematic reviews and meta-analysis about the evaluation of antioxidants for cancer prevention were selected. Results: the carcinogenic mechanisms of oxygen reactive species, and the benefits and threats of antioxidant supplementation are discussed. Finally, the possible impact on oxidative stress control, of implementation of the WHO Global Strategy on Diet Physical Activity and Health is analyzed, empathizing in the anticarcinogenic mechanisms of different phytochemicals. Conclusions: the promotion of healthy habits which avoid the generation of oxygen reactive species, together with the intake of antioxidants as dietary components could lead to the appropriate balance oxidants/antioxidants and consequently to cancer prevention.

DNA damage by reactive species: Mechanisms, mutation and repair.

DNA is continuously attacked by reactive species that can affect its structure and function severely. Structural modifications to DNA mainly arise from modifications in its bases that primarily occur due to their exposure to different reactive species. Apart from this, DNA strand break, inter- and intra-strand crosslinks and DNA–protein crosslinks can also affect the structure of DNA significantly. These structural modifications are involved in mutation, cancer and many other diseases. As it has the least oxidation potential among all the DNA bases, guanine is frequently attacked by reactive species, producing a plethora of lethal lesions. Fortunately, living cells are evolved with intelligent enzymes that continuously protect DNA from such damages. This review provides an overview of different guanine lesions formed due to reactions of guanine with different reactive species. Involvement of these lesions in inter- and intra-strand crosslinks, DNA–protein crosslinks and mutagenesis are discussed. How certain enzymes recognize and repair different guanine lesions in DNA are also presented.

Free Radical Scavenging and In-vitro Antioxidant Effects of Ethanol Extract of the Medicinal Herb Chromolaena odorata Linn.

The ethanol extract of the leaf of Chromolaena odorata (Linn) was assessed for freeradical- scavenging and antioxidant potentials. Ability of the extract to scavenge reactive intermediates (superoxide ion O2 ·-, hydrogen peroxide H2O2, nitric oxide NO˙, hydroxyl radical OH˙) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, were used to assess its free radical scavenging potentials. Antioxidant potential was studied by assessing invitro inhibition of lipid peroxidation in both the brain (Neuro-protective potentials) and liver homogenates of Fenton-oxidant stressed rabbits. Inhibition of protein oxidation was assessed in-vitro by loss of protein thiol (P-SH), while assessment of the reducing power of the extract was further used to assess antioxidant capacity. Results obtained showed the ability of the extract to scavenge free radicals and reactive intermediates in a dose-response manner. The plant also had good antioxidant capacity. The secondary plant metabolites found earlier in the extract may explain reasons for the bio-efficacy of the plant. These findings are of great importance in view of the availability of the plant and its observed possible diverse applications in medicine and nutrition.

TBARS level in socioeconomical poor rural sickle cell patients of Bilaspur Zone of Chhattisgarh State.

Sickle cell disease (SCD) is an inherited disorder of hemoglobin synthesis and the oxidative stress has major role in the pathogenesis of SCD. Thiobarbituric acid reactive substances formation by lipid peroxidation is a marker of oxidative damage in membrane.The study was under taken to measure the oxidative stress in sickle cell patients of Chhattisgarh rural population because of low natural antioxidants in their diet. The patients of sickle cell anemia group (homozygous, n=9) and sickle cell trait (heterozygous, n=21) shows TBARS level 2.28±0.66μM/l and 2.23±0.7μM/l respectively as compared to control (without S.C.D) 1.25±0.41μM/l. the study shows TBARS concentration is approximately double in sickle cell disease than control.

Plasma cytokine response, lipid peroxidation and NF-kB activation in skeletal muscle following maximum progressive swimming

Our objective was to determine lipid peroxidation and nuclear factor-κB (NF-κB) activation in skeletal muscle and the plasma cytokine profile following maximum progressive swimming. Adult male Swiss mice (N = 15) adapted to the aquatic environment were randomly divided into three groups: immediately after exercise (EX1), 3 h after exercise (EX2) and control. Animals from the exercising groups swam until exhaustion, with an initial workload of 2 percent of body mass attached to the tail. Control mice did not perform any exercise but were kept immersed in water for 20 min. Maximum swimming led to reactive oxygen species (ROS) generation in skeletal muscle, as indicated by increased thiobarbituric acid reactive species (TBARS) levels (4062.67 ± 1487.10 vs 19,072.48 ± 8738.16 nmol malondialdehyde (MDA)/mg protein, control vs EX1). Exercise also promoted NF-κB activation in soleus muscle. Cytokine secretion following exercise was marked by increased plasma interleukin-6 (IL-6) levels 3 h post-exercise (P < 0.05). Interleukin-10 (IL-10) levels were reduced following exercise and remained reduced 3 h post-exercise (P < 0.05). Plasma levels of other cytokines investigated, monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ) and interleukin-12 (IL-12), were not altered by exercise. The present findings showed that maximum swimming, as well as other exercise models, led to lipid peroxidation and NF-κB activation in skeletal muscle and increased plasma IL-6 levels. The plasma cytokine response was also marked by reduced IL-10 levels. These results were attributed to exercise type and intensity.

Vitaminas e minerais com propriedades antioxidantes e risco cardiometabólico: controvérsias e perspectivas: [revisão] / Vitamins and minerals with antioxidant properties and cardiometabolic risk: controversies and perspectives: [review]

No processo celular de obtenção de energia, são gerados compostos chamados espécies reativas de oxigênio (ERO) que, em excesso, podem causar danos celulares. Estresse oxidativo resulta do desequilíbrio no estado de óxido-redução a favor da oxidação. Dos mecanismos de defesa antioxidante, participam enzimas endógenas e algumas vitaminas e minerais. A vitamina E encontra-se no plasma e na partícula de LDL, protegendo lipídeos da oxidação. Estudos observacionais relataram associação inversa entre ingestão de vitamina E e risco cardiometabólico (RCM). Entretanto, ensaios clínicos não comprovaram a eficácia de sua suplementação nos desfechos cardiometabólicos. A vitamina C participa do sistema de regeneração da vitamina E, mantendo o potencial antioxidante plasmático. Dados sobre os benefícios de sua suplementação na redução do risco cardiometabólico são inconclusivos. A atividade antioxidante dos carotenoides é responsável, em parte, por seu papel protetor contra doenças cardiovasculares e cânceres. A suplementação desse nutriente também não trouxe resultados consistentes no que se refere à redução do RCM. A participação do zinco e do selênio na defesa antioxidante vem sendo estudada mais recentemente, mas a sua suplementação em indivíduos com níveis séricos normais e ingestão adequada na dieta desses minerais não parece ser necessária. De um modo geral, há muita controvérsia sobre o papel desses micronutrientes no RCM. Estudos epidemiológicos sugerem que o consumo de substâncias antioxidantes provenientes da dieta ou dietas ricas em frutas e hortaliças diminui o RCM. Mais estudos são necessários antes de se recomendar o uso de antioxidantes isolados na forma de suplementos para tal finalidade.

Oxygen reactive species (ROS) are generated during cellular processes. In excess, they may cause damages to the cell. Oxidative stress is an imbalance in the redox state that favors oxidation. Endogenous enzymes and some vitamins and minerals participate in the plasma antioxidant defense. Vitamin E is found in the plasma and in the LDL particle, avoiding lipid peroxidation. Observational studies reported an inverse association between vitamin E consumption and cardiometabolic (CM) risk. However, clinical trials were not able to prove the efficacy of its supplementation on CM endpoints. Vitamin C participates in the vitamin E regeneration system, keeping the plasma's antioxidant potential. Data about beneficial effects of its supplementation in CM risk reduction are inconclusive. The antioxidant activity of carotenoids is partially responsible for its protective role against cardiovascular diseases and cancer. Supplementation of this nutrient did not provide consistent findings in terms of CM risk reduction. Recently, zinc and selenium's participation in the antioxidant defense has been studied, yet its supplementation in individuals with normal levels and adequate ingestion of these nutrients does not seem necessary. In summary, the role of these micronutrients for CM risk is still very controversial. Epidemiological studies suggest that diets rich in antioxidants, or simply in fruit and vegetables intake, can reduce CM risk. Further studies are needed before recommending antioxidant supplements for this purpose.

Estresse oxidativo: avaliação de marcadores / Oxidative stress: assessment of biomarkers

The onset of oxidative stress is caused by an imbalance between theproduction of reactive species and antioxidant defense. In essence, it wasdefi ned as a disturbance in the pro-oxidant/antioxidant balance in favorof the former, leading to the oxidation of biomolecules and a consequentloss of their biological functions and/or homeostatic imbalance, manifestedthrough potential oxidative damage to cells and tissues. Oxidative damageinvolves the attack of free radicals and reactive species against varioussubstrates, including lipids, nucleic acids and proteins. Oxidative stress hasbeen suggested to be involved in the etiology of a host of chronic diseasesincluding cardiovascular disease, diabetes, cancer and neurodegenerativeprocesses. The assessment of biomarkers of oxidative stress has acquiredimportance as a tool in diagnosis and control of the associated process. Inthis review, the present study will examine the major biomarkers and themethods available to measure oxidative stress

Este trabajo tiene por objetivo revisar losprincipales marcadores del estrés oxidativo, asícomo sus técnicas de evaluación. La instalacióndel proceso de estrés oxidativo ocurre por laexistencia de un desequilibrio entre los sistemasoxidativo y antioxidante que favorece alprimero. Ese proceso conduce a la oxidaciónde biomoléculas que pierden sus funcionesbiológicas y/o el desequilibrio homeostático. Sumanifestación es el daño oxidativo potencialcontra células y tejidos. La cronicidad de esteproceso tiene importantes implicaciones en eldesarrollo de las enfermedades crónicas notransmisibles: obesidad, aterogénesis, diabetes,trastornos neurodegenerativos y cáncer. Esimportante identifi car marcadores para evaluarel estrés oxidativo y sistematizar su utilizaciónen el diagnóstico y control de los efectos adversosdel proceso. Esos esfuerzos se concentran en losproductos de la oxidación de lípidos, proteínasy ácido desoxirribonucleico. Otra forma deabordar la evaluación del estrés oxidativo esa través de métodos indirectos, basados en lacapacidad antioxidante.

A instalação do processo de estresse oxidativodecorre da existência de um desequilíbrio entrecompostos oxidantes e antioxidantes, em favordos primeiros. Tal processo conduz à oxidaçãode biomoléculas com conseqüente perda desuas funções biológicas e/ou desequilíbriohomeostático, cuja manifestação é o danooxidativo potencial contra células e tecidos.A cronicidade de tal processo demonstraimportantes implicações sobre a etiologia deenfermidades crônicas transmissíveis, entre elas:aterosclerose, diabetes, obesidade, transtornosneurodegenerativos e câncer. É de extremaimportância a identifi cação de marcadores paraa avaliação do estresse oxidativo, no sentido desistematizar o emprego destes no diagnóstico econtrole dos efeitos adversos de tal processo. Osmarcadores em questão se baseiam nos produtosda oxidação de lipídios, proteínas e DNA, ouainda na aferição da capacidade antioxidante.O presente estudo visa revisar os principaismarcadores, bem como as técnicas de análisepara a avaliação do estresse oxidativo.

Aspectos atuais sobre estresse oxidativo, exercícios físicos e suplementação / Current aspects about oxidative stress, physical exercise and supplementation

As espécies reativas de oxigênio (ERO) são normalmente produzidas pelo metabolismo corporal. Todavia, ERO apresentam a capacidade de retirar elétrons de outros compostos celulares, sendo capazes de provocar lesões oxidativas em várias moléculas, fato que leva à perda total da função celular. A realização de exercícios físicos aumenta a síntese de ERO, além de promover lesão muscular e inflamação. Após uma sessão de exercícios físicos, inicia-se normalmente a fase de recuperação, quando são observados diversos efeitos positivos à saúde, incluindo o aumento da resistência a novas lesões induzidas ou não por exercícios, fato que é considerado como um processo "adaptativo". Diversos estudos, porém, relatam que essa recuperação não é alcançada por indivíduos que se submetem a exercícios intensos e prolongados, ou, ainda, que possuem elevada freqüência de treinamento. Alternativas nutricionais têm sido muito estudadas, a fim de reduzir os efeitos promovidos pelo exercício extenuante, dentre as quais está a suplementação com vitamina E, vitamina C, creatina e glutamina. Esta revisão tem como objetivo abordar os aspectos atuais envolvendo a formação das ERO, os processos de lesão celular e inflamação, a adaptação aos tipos de exercício aeróbio e anaeróbio e possíveis intervenções nutricionais.

Oxygen reactive species (ORE) are usually produced by the body metabolism. However, ORE present the ability to remove electrons from other cellular composites, being able to cause oxidative injuries in several molecules. Such fact leads to a total loss of cellular function. Physical exercise practice increases ORE synthesis, besides promoting muscular injury and inflammation. After a physical exercise set, the recovery phase begins, where several effects positive to health are observed, including increase in resistance to new injuries induced or not by exercise, a fact which is considered an 'adaptation' process. Many studies though, have reported that this recovery is not reached by individuals who are submitted to intense and extended exercises, or even, who have high training frequency. Nutritional alternatives have been widely studied, in order to reduce the effects promoted by extenuating exercise, among which vitamin E, vitamin C, creatine and glutamine supplementation is included. This review has the aim to approach the current aspects concerning the ORE formation, the cellular injury and inflammation processes, the adaptation to the kinds of aerobic and anaerobic exercise, besides possible nutritional interventions.

Perspectivas del uso de antioxidantes como coadyuvantes en el tratamiento del asma / Perspectives in the use of antioxidants for the treatment of asthma

Al tratarse de un proceso inflamatorio, en el asma hay participación e incremento en la generación de especies reactivas del oxígeno, dando lugar a un desequilibrio oxidante/antioxidante, fenómeno que se ha descrito como estrés oxidante, que causa daño a diferentes biomoléculas. La utilización de agentes antioxidantes exógenos o activadores de antioxidantes endógenos como coadyuvantes de la terapéutica del paciente asmático, es una posibilidad a discutir.

Oxidative stress seen in bronchial asthma can damage different kinds of biomolecules; this oxidant/antioxidant imbalance results from an increment in the production of oxygen reactive species. The utilization of exogenous antioxidant agents or promoters of endogenous antioxidants can be seen as an alternative therapy for asthma that is worth discussing.

The progress in the mechanisms of methamphetamine neurotoxicity / 中国药理学通报

Research into methamphetamine-induced neurotoxicity has experienced a resurgence in recent years. This is due to an increased abuse of the substance internationally. The long-term abuse of methamphetamine will result in neurochemical, neuropathological and behavioral changes. Recent data implicate that dopamine oxidation, glutamate-induced excitotoxicity, disruption of mitochondria, and apoptosis are involved in the injury of methamphetamine to central nervous system. Further, Involvement of cell death-related genes in the neurotoxic effects of methamphetamine is also discussed.