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1.
Indian J Dermatol Venereol Leprol ; 89(4): 501-509, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36461796

RESUMO

Aims To examine the differences in the levels of microRNA, ischemic modified albumin (IMA), total oxidant capacity (TOC), and total antioxidant capacity (TAC) of persons with and without psoriasis and, in the case group, the relationship between these parameters and psoriasis area and severity index (PASI). Methods Blood samples were collected from patients and healthy participants to examine levels of these parameters. Results The mean serum TOC level was higher in the case group. The mean serum TAC and IMA levels were significantly lower in the case group (P <0.001). It was observed that the mean serum miR-203 and miR-146a levels were increased in psoriasis patients. It was determined that there was only a significant positive weak correlation between miR-203 and PASI (r = 0.232, P = 0.027). Limitations The small sample size, not controlling serum albumin and not evaluating the effects of the treatment agents used by the patients on oxidative and inflammatory processes. Conclusion In the case group changes in the mean serum TOC and TAC levels provide evidence that oxidative stress may play a critical role in disease pathogenesis. The increase in the mean serum miR-203 and miR-146a levels suggest the possibility of therapies targeting these microRNAs as a new option.


Assuntos
MicroRNAs , Psoríase , Humanos , Antioxidantes/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Oxidantes , Albumina Sérica , Psoríase/diagnóstico , Psoríase/genética , Estresse Oxidativo , Estudos de Casos e Controles , Biomarcadores
2.
Food Chem ; 409: 135277, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36586271

RESUMO

Lycium barbarum and Polygonatum cyrtonema are known for their medicinal, edible, and ornamental properties. The sensory indices of the novel high-quality L. barbarum and P. cyrtonema compound wine (LPCW) fermented by Saccharomyces cerevisiae RW and Debaryomyces hansenii AS2.45 under different inoculation methods were analyzed. The alcohol content of the LPCW ranged from 3.88 to 4.75 % under three mixed inoculations. The total saponin and total polysaccharide contents in LPCW inoculated with D. hansenii first and S. cerevisiae after 24 h were 4.39 mg/mL and 0.21 mg/mL, respectively. Ethyl butyrate, citronellol, and 3-(methylthio) propanol were unique metabolites of D. hansenii. 4-Methoxybenzoic acid was the core product of brewing of by S. cerevisiae. Except for wine inoculated with S. cerevisiae only, the acceptability scores of all the LPCW samples were higher than 7.3. Our data provided the foundation for the development and application of medicinal and food homologous substances in food fermentation.


Assuntos
Lycium , Polygonatum , Vinho , Fermentação , Saccharomyces cerevisiae/metabolismo , Vinho/análise , Polygonatum/metabolismo , Lycium/metabolismo , Antioxidantes/metabolismo
3.
Indian J Dermatol Venereol Leprol ; 89(3): 411-415, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35962507

RESUMO

Background Alopecia areata is a chronic inflammatory skin disease. Oxidative stress may contribute to the pathogenesis of this condition. Aim To evaluate the serum oxidative stress markers and antioxidant capacity in patients with alopecia areata. Methods This cross-sectional study was performed on 40 patients with alopecia areata and 40 healthy controls. The fasting blood sugar, C-reactive protein, lipid profile, and serum oxidative markers, including advanced glycation end products and advanced oxidation protein products, were measured in this study. Also, antioxidant enzymes, including paraoxonase-1, lecithin-cholesterol acyltransferase and serum ferric-reducing antioxidant power, were determined. Results The serum levels of advanced glycation end products and advanced oxidation protein products were significantly higher in patients with alopecia areata, compared to the controls (P < 0.001), whereas the levels of ferric-reducing antioxidant power, paraoxonase-1 and lecithin-cholesterol acyltransferase were significantly lower in patients with alopecia areata, compared to the controls (P < 0.001). The mean fasting blood sugar level was significantly higher in patients with alopecia areata, compared to the controls. The ferric reducing antioxidant power level was significantly associated with the percentage of hair loss (P = 0.01, r = 0.4) and the serum C-reactive protein level (P = 0.03, r = -0.3) in patients with alopecia areata. Limitations Since the current study had a cross-sectional design, no cause-effect relationship was established between alopecia areata and oxidative stress. The sample size of our study was also small. Conclusion Based on the present results, the oxidant-antioxidant enzymatic system is impaired in alopecia areata due to the increased oxidative products and decreased antioxidant activity.


Assuntos
Alopecia em Áreas , Antioxidantes , Humanos , Antioxidantes/metabolismo , Alopecia em Áreas/metabolismo , Estudos Transversais , Proteína C-Reativa , Arildialquilfosfatase , Produtos da Oxidação Avançada de Proteínas/metabolismo , Glicemia , Lecitinas , Esterol O-Aciltransferase/metabolismo , Estresse Oxidativo , Biomarcadores , Doença Crônica
4.
PLoS Negl Trop Dis ; 14(10): e0008749, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33044965

RESUMO

Leprosy reduces quality of life of affected persons. Oxidative stress caused by reactive oxygen species may play a vital role in the pathogenesis of leprosy. This study evaluated anthropometric indices, fasting plasma glucose (FPG), lipid profile, total antioxidant capacity (TAC), total plasma peroxide (TPP), oxidative stress index (OSI), malondialdehyde (MDA), glutathione (GSH) and 8-hydroxy-2-deoxyguanosine (8-OHdg) in leprosy patients. Sixty test participants of both genders, aged 18-65years and diagnosed of multibacillary leprosy and 30 apparently healthy controls were consecutively recruited for this study. The test participants comprised of 30 patients on multidrug therapy (MDT) and 30 patients relieved from therapy (RFT). Body mass index (BMI), Waist-hip ratio (WHR), FPG, lipid profile, TAC, TPP, OSI, MDA, GSH and 8-OHdg were determined using appropriate methods. Data were analyzed using Analysis of variance; p<0.05 was considered statistically significant. The MDT group had significantly lower BMI (p = 0.0001), Total cholesterol (p = 0.001), HDL-C (p = 0.019), LDL-C (p = 0.005), TAC (p = 0.0001) and higher TPP (p = 0.001), MDA (p = 0.0001), OSI (p = 0.005) and 8-OHdg (p = 0.035) compared to the controls. The RFT group had significantly lower BMI (p = 0.001) Total cholesterol (0.0001), HDL-C (p = 0.006) LDL-C (p = 0.0001), TAC (p = 0.001) and higher WHR (p = 0.010), VLDL-C (p = 0.035), TG (p = 0.023) Atherogenic index of plasma (p = 0.0001) and TPP (p = 0.001), MDA (p = 0.0001) compared to the control group. GSH levels correlated negatively with duration of treatment (r = -0.401, p = 0.028). This study has shown that there is oxidative stress in multibacillary leprosy patients irrespective of drug treatment status. This study also shows that leprosy patients relieved from treatment may be susceptible to cardiovascular events. Antioxidants supplementation may be beneficial in the treatment of leprosy and clinical follow up on patients relieved from treatment may also be necessary to monitor health status and prevent development of cardiovascular events.


Assuntos
Doenças Cardiovasculares/microbiologia , Dano ao DNA , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Estresse Oxidativo , Adulto , Antioxidantes/metabolismo , Biomarcadores/sangue , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , Estudos de Casos e Controles , Quimioterapia Combinada , Feminino , Glutationa/sangue , Humanos , Hanseníase/sangue , Masculino , Malondialdeído/farmacologia , Pessoa de Meia-Idade , Nigéria , Fatores de Risco , Adulto Jovem
5.
Cancer Chemother Pharmacol ; 85(3): 563-571, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31915967

RESUMO

PURPOSE: It has been supposed that cardiac toxicity of doxorubicin is due to its production of free radicals and inflammatory cytokines. Dapsone, an antibiotic drug which is the principal in a multidrug regimen for the treatment of leprosy, is a sulfone with anti-inflammatory and antioxidant immunosuppressive properties. Therefore, we designed this study to investigate the possible effects of dapsone on doxorubicin-induced cardiotoxicity. METHODS: Male rats were administrated doxorubicin (2.5 mg/kg) and dapsone (1, 3, 10 mg/kg) intraperitoneally six times in 2 weeks. Then electrocardiographic (ECG) parameters (QRS complexes, RR and QT intervals) alternation, papillary muscle contraction and excitation, and histopathological changes were assessed. Also, the heart tissue levels of malondialdehyde (MDA) as oxidant factor and superoxide dismutase (SOD) as antioxidant enzyme, tumor necrosis factor-alpha (TNF-α) and serum level of CK-MB were analyzed. RESULTS: Administration of dapsone with doxorubicin significantly reversed alterations induced by doxorubicin in serum levels of CK-MB, ECG parameters, papillary muscle contractility and excitation. Furthermore, the measurement of MDA, SOD and TNF-α tissue level indicated that dapsone significantly reduced oxidative stress and inflammation. These findings were consistent with histopathological analysis. CONCLUSION: Dapsone exerts cardioprotective effects on doxorubicin-induced cardiotoxicity through its anti-inflammatory and antioxidant mechanism.


Assuntos
Cardiotoxicidade/tratamento farmacológico , Dapsona/farmacologia , Doxorrubicina/efeitos adversos , Coração/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Cardiotoxicidade/metabolismo , Citocinas/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Masculino , Malondialdeído/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
6.
Appl Microbiol Biotechnol ; 103(5): 2339-2352, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30656393

RESUMO

Several marine Debaryomyces hansenii strains have shown probiotic effects on aquatic animals, and D. hansenii-derived ß-glucans have recently provided immunostimulant effects on goat leukocytes. This study assessed the probiotic effects of live yeast D. hansenii CBS 8339 on newborn goats administered orally, and subsequently challenged in vitro with Escherichia coli. D. hansenii CBS 8339 demonstrated the capacity to survive gastrointestinal tract conditions (bile salts and acid pH tolerance) and adhere to goat intestine. Twelve Saanen × Nubian crossbred newborn goats (2.9 ± 0.47 kg) were fed with a controlled diet or D. hansenii (0.7 g/kg body weight per day)-supplemented milk for 30 days. Blood samples of newborn goats were taken at days 15 and 30, and peripheral blood leukocytes were isolated for bacterial challenge, and immunological and antioxidant analyses. Despite cell viability was higher in leukocytes of goat kids fed with the yeast supplement, protection against E. coli challenge was not significantly affected. On the other hand, at day 15, oral administration of D. hansenii enhanced respiratory burst and catalase activity and increased superoxide dismutase activity after challenge. In contrast, at day 30, administration of the yeast supplement increased peroxidase activity and enhanced nitric oxide production and catalase activity after challenge. Finally, the yeast-supplemented diet upregulated the expression of the receptor genes TLR (2, 4, 6), modulator genes Raf.1, Syk, and Myd88, transcription factor gene AP-1, and cytokine genes IL-1ß and TNF-α only at day 15 in leukocytes from unchallenged goat kids. These results demonstrated that a short time (15 days) of orally administering the probiotic D. hansenii CBS 8339 to newborn goats stimulated innate immune and antioxidant parameters and the expression of immune-related gene signaling pathways.


Assuntos
Animais Recém-Nascidos/microbiologia , Antioxidantes/metabolismo , Debaryomyces/metabolismo , Cabras/microbiologia , Imunidade Inata/imunologia , Probióticos/metabolismo , Animais , Catalase/metabolismo , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/fisiologia , Leucócitos/citologia , Óxido Nítrico/metabolismo , Explosão Respiratória/fisiologia , Superóxido Dismutase/metabolismo , beta-Glucanas/metabolismo
8.
Indian J Lepr ; 87(1): 17-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26591846

RESUMO

The aim of the study is to assess the role of saliva as a diagnostic tool for measurement of total antioxidant capacity in children with leprosy and children born to leprosy parent. One hundred fifty children in the age group of 4-15 years were split into three equal groups: children with leprosy (CL) and children born to leprotic parents (CLP) and healthy children. Vitamin C level was measured in saliva of children spectrophotometrically at 695nm by Phosphomolybdenum method. Data were determined with student's unpaired t test and one way ANOVA. The result of the study showed that children with leprosy exhibited significantly decreased salivary total antioxidant capacity as compared to healthy controls. Antioxidant Vitamin C was higher in the Paucibacillary leprosy (PB) than those of Multibacillary type (MB) (P < 0.001). As age advanced, there was a gradual increase in total antioxidant capacity in both the control and study groups and the results were highly significant statistically. Saliva is an easy medium.


Assuntos
Antioxidantes/análise , Testes Diagnósticos de Rotina/métodos , Hanseníase/diagnóstico , Saliva/química , Adolescente , Antioxidantes/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Hanseníase/metabolismo , Masculino , Saliva/metabolismo
9.
World J Microbiol Biotechnol ; 31(12): 1899-906, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26475328

RESUMO

The use of supplements in the diet is a common practice to address nutritional deficiencies. Selenium is an essential micronutrient with an antioxidant and anti-carcinogenic role in human and animal health. There is increasing interest in developing nutritional supplements such as yeast cells enriched with selenium. The possibility of producing beverages, namely wine, with selenium-enriched yeasts, led us to investigate the selenium tolerance of six wine related yeasts. The production of such cells may hamper selenium toxicity problems. Above certain concentrations selenium can be toxic inducing oxidative stress and yeast species can show different tolerance. This work aimed at studying selenium tolerance of a diversity of wine related yeasts, thus antioxidant response mechanisms with different concentrations of sodium selenite were evaluated. Viability assays demonstrated that the yeast Torulaspora delbrueckii showed the highest tolerance for the tested levels of 100 µg mL(-1) of sodium selenite. The evaluation of antioxidative enzyme activities showed the best performance for concentrations of 250 and 100 µg mL(-1), respectively for the yeast species Saccharomyces cerevisiae and Hanseniaspora guilliermondii. These results encourage future studies on the possibility to use pre-enriched yeast cells as selenium supplement in wine production.


Assuntos
Antioxidantes/farmacologia , Selenito de Sódio/farmacologia , Vinho/microbiologia , Leveduras/enzimologia , Antioxidantes/análise , Antioxidantes/metabolismo , Meios de Cultura , Relação Dose-Resposta a Droga , Fermentação , Hanseniaspora/enzimologia , Hanseniaspora/crescimento & desenvolvimento , Hanseniaspora/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Selenito de Sódio/metabolismo , Torulaspora/enzimologia , Torulaspora/crescimento & desenvolvimento , Torulaspora/metabolismo , Leveduras/efeitos dos fármacos , Leveduras/metabolismo
10.
Indian J Lepr ; 85(1): 5-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24046909

RESUMO

Oxidative stress is a condition associated with an increased rate of cellular damage induced by the oxygen derived oxidants commonly known as reactive oxygen species (ROS). ROS are capable of damaging cellular constituents generated in excess during the chronic, inflammatory, neurodegenerative disease process of leprosy. Severe oxidative stress has been reported in leprosy patients because of malnutrition and poor immunity. The decreased levels of SOD, glutathione and total antioxidant status in leprosy patients may indicate a degradation of these antioxidant enzymes by free radicals during detoxification processes. The subjects for this study comprises of Normal human volunteers (NHV, n = 20) and treated MB patients (MB, n = 20). The levels of lipid peroxidation products are increased in MB Patients (*P < 0.001). SOD (**P < 0.0001) and glutathione levels (***P < 0.0001) decreased in MB Patients in comparision with normal human volunteers. The present study of estimation of antioxidants conclude that the free radical activity was increased and the total antioxidant status was decreased in all MB patients, indicating that there was an oxidative stress even after the treatment with MDT. The decreased levels of SOD, glutathione indicate a link between oxidative stress and leprosy. Since the MB patients are unable to produce sufficient amount of antioxidant to cope up with the increased oxidative stress in them. Providing nutritional supplementation may present a novel approach for fast recovery. Administration of exogenous antioxidants like vitamin C, tocopherols would prevent tissue damage and make the patient therapeutically benefited.


Assuntos
Antioxidantes/metabolismo , Hanseníase/sangue , Espécies Reativas de Oxigênio/metabolismo , Estudos de Casos e Controles , Radicais Livres , Glutationa/sangue , Humanos , Hanseníase/tratamento farmacológico , Peroxidação de Lipídeos , Malondialdeído/sangue , Estresse Oxidativo/fisiologia , Superóxido Dismutase/sangue
12.
Artigo em Inglês | MEDLINE | ID: mdl-18188882

RESUMO

BACKGROUND: The study and assessment of oxidative stress plays a significant role in the arena of leprosy treatment. Once the presence of oxidative stress is proved, antioxidant supplements can be provided to reduce tissue injury and deformity. AIM: To study oxidative stress in paucibacillary (PB) and multibacillary (MB) leprosy and to compare it with that in a control group. METHODS: Fifty-eight untreated leprosy patients (23 PB and 35 MB cases) were studied and compared with 58 healthy controls. Superoxide dismutase (SOD) level as a measure of antioxidant status; malondialdehyde (MDA)level, an indicator of lipid peroxidation; and MDA/SOD ratio, an index of oxidative stress were estimated in the serum. RESULTS: The SOD level was decreased in leprosy patients, especially in MB leprosy. The MDA level was increased in PB and MB leprosy. The MDA/SOD ratio was significantly elevated in MB patients. There was a steady increase in this ratio along the spectrum from tuberculoid to lepromatous leprosy (LL). CONCLUSION: There is increased oxidative stress in MB leprosy, especially in LL. This warrants antioxidant supplements to prevent tissue injury.


Assuntos
Antioxidantes/metabolismo , Hanseníase/metabolismo , Estresse Oxidativo , Pele/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Hanseníase/classificação , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Superóxido Dismutase/metabolismo
13.
Mol Pharm ; 5(6): 1138-44, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19434859

RESUMO

Thalidomide as an effective treatment for multiple myeloma and leprosy has also caused birth defects in thousands of children five decades ago particularly in Europe. Thus its use in humans remains limited. The rapid and fatal approval of thalidomide at that time ultimately was a consequence of the sole use of thalidomide-insensitive species in animal toxicity tests. Here, we aimed at elucidating the molecular basis for the resistance of mice to thalidomide teratogenicity. By using hydroethidine staining we demonstrate that thalidomide induces the formation of superoxide in embryonic fibroblasts of thalidomide-sensitive species but not in those of mice. As determined by trypan blue staining, scavenging of superoxide prevents thalidomide-induced apoptosis, a marker for thalidomide teratogenicity. Mouse embryonic fibroblasts are found to have higher glutathione levels than those of sensitive species and can be sensitized for thalidomide by glutathione depletion with diethyl maleate or diamide. Accordingly, experimental increase of glutathione levels in human embryonic fibroblasts by adding N-acetyl cysteine or glutathione ethyl ester to the culture medium counteracts thalidomide-induced apoptosis. Finally, we show that thalidomide-induced molecular pathology downstream of superoxide is essentially identical in human and sensitized mouse embryonic fibroblasts. In conclusion, thalidomide-resistance is based on the capacity of the glutathione-dependent antioxidant defense. We provide a basis to pharmacologically overcome the limitations of thalidomide use at humans and describe substantial differences between human and mouse embryonic cells regarding the protection against oxidative stress.


Assuntos
Antioxidantes/metabolismo , Resistência a Medicamentos/efeitos dos fármacos , Glutationa/metabolismo , Teratogênicos/farmacologia , Talidomida/farmacologia , Acetilcisteína/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Galinhas , Meios de Cultivo Condicionados/farmacologia , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Embrião não Mamífero , Fibroblastos/metabolismo , Sequestradores de Radicais Livres/farmacologia , Glutationa/análogos & derivados , Glutationa/análise , Glutationa/farmacologia , Humanos , Camundongos , Superóxidos/metabolismo , Fatores de Tempo
14.
Mar Biotechnol (NY) ; 9(3): 343-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17345116

RESUMO

The extracellular alkaline protease in the supernatant of cell culture of the marine yeast Aureobasidium pullulans 10 was purified to homogeneity with a 2.1-fold increase in specific protease activity as compared to that in the supernatant by ammonium sulfate fractionation, gel filtration chromatography (Sephadex G-75), and anion-exchange chromatography (DEAE Sepharose Fast Flow). According to the sodium dodecyl sulfate-polyacrylamide gel electrophoresis data, the molecular mass of the purified enzyme was estimated to be 32.0 kDa. The optimal pH and temperature of the purified enzyme were 9.0 and 45 degrees C, respectively. The enzyme was activated by Cu(2+) (at a concentration of 1.0 mM) and Mn(2+) and inhibited by Hg(2+), Fe(2+), Fe(3+), Zn(2+), and Co(2+). The enzyme was strongly inhibited by phenylmethylsulfonyl fluoride, but weakly inhibited by EDTA, 1-10-phenanthroline, and iodoacetic acid. The K(m) and V(max) values of the purified enzyme for casein were 0.25 mg/ml and 0.0286 micromol/min/mg of protein, respectively. After digestion of shrimp protein, spirulina (Arthospira platensis) protein, proteins of marine yeast strains N3C (Yarrowia lipolytica) and YA03a (Hanseniaspora uvarum), milk protein, and casein with the purified alkaline protease, angiotensin I converting enzyme (ACE) inhibitory activities of the resulting peptides reached 85.3%, 12.1%, 29.8%, 22.8%, 14.1%, and 15.5%, respectively, while the antioxidant activities of these were 52.1%. 54.6%, 25.1%, 35%, 12.5%, and 24.2%, respectively, indicating that ACE inhibitory activity of the resulting peptides from the shrimp protein and antioxidant activity of those produced from the spirulina protein were the highest, respectively. These results suggest that the bioactive peptides produced by digestion of the shrimp protein with the purified alkaline protease have potential applications in the food and pharmaceutical industries.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Endopeptidases/isolamento & purificação , Endopeptidases/metabolismo , Peptídeos/metabolismo , Leveduras/enzimologia , Animais , Antioxidantes/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/biossíntese , Cátions/farmacologia , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Endopeptidases/biossíntese , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Metais/farmacologia , Peptídeos/genética , Inibidores de Proteases/farmacologia , Especificidade por Substrato , Leveduras/genética
15.
Plant Physiol Biochem ; 44(4): 193-201, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16762559

RESUMO

A robust spectroscopic method for determining total antioxidant activity in aqueous extractions has been applied to tissues from diverse woody plant species, including seeds of Coffea arabica and in vitro shoots from Ribes nigrum, Picea sitchensis and Shorea leprosula. The assay involves scavenging of an ABTS [2,2'-azinobis-(3-ethyl-benzothiazoline-6-sulphonic acid)] radical generated by the reaction of potassium persulphate with ABTS to produce an ABTS*(+) chromophore (lambda=734 nm). Antioxidants reduce ABTS*(+) back to ABTS with a concomitant decrease in absorbance. Aqueous extractions from C. arabica and S. leprosula had considerably higher (110-205 micromol Trolox eq. g(-1) FW) total antioxidant activities than P. sitchensis and R. nigrum (6-11 micromol Trolox eq. g(-1) FW). Further studies in two of these species showed that the inclusion of water-insoluble polyvinylpyrrolidone during aqueous tissue extraction enabled the combined phenolic and alkaloid antioxidant activity to be determined. These fractions accounted for 85% and 60% of total antioxidant activity for C. arabica seeds and R. nigrum shoots, respectively. The ABTS radical scavenging assay is presented herein as a robust method for determining total antioxidant activity in germplasm from diverse woody plant tissues and species. Its applicability to study oxidative stress in tissue cultures and germplasm employed in plant biotechnology, breeding and stress physiology programmes is discussed.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Benzotiazóis/química , Brotos de Planta/química , Brotos de Planta/metabolismo , Ácidos Sulfônicos/química , Madeira , Coffea/química , Coffea/metabolismo , Ericales/química , Ericales/metabolismo , Picea/química , Picea/metabolismo , Ribes/química , Ribes/metabolismo , Sementes/química , Sementes/metabolismo , Fatores de Tempo
16.
Indian J Lepr ; 75(4): 307-16, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15242269

RESUMO

Severe oxidative stress has been reported in leprosy patients because of malnutrition and poor immunity. The purpose of this study was to investigate the serum lipid peroxidation products, serum LDH and important free radical scavenging enzymes, i.e. superoxide dismutase (SOD), and catalase and anti-oxidant glutathione levels and total anti-oxidant status, in different types of leprosy patients. The subjects for this study were normal human volunteers (NHVs, n=14), paucibacillary leprosy patients (PB, n=18), untreated MB patients (MB1, n=18), MB patients under treatment (MB2, n=19), and MB patients released from treatment (RFT) (MB3, n=28). The levels of lipid peroxidation product, malondialdehyde (MDA), and LDH increased significantly (p<0.001) in MB (MB1, MB2, MB3) patients, and both gradually decreased with clinical improvement following MDT. The levels of SOD, catalase and glutathione, and the total anti-oxidant status decreased significantly in MB (MB1, MB2, MB3) patients (p<0.001), in comparison with NHVs. They gradually increased with clinical improvement with MDT. There was no significant variation of these parameters in PB leprosy patients in comparison with healthy volunteers. High free radical activity and low anti-oxidant levels observed in MB (MB1, MB2, MB3) leprosy patients indicate that there is an oxidative stress in MB cases, irrespective of the treatment status and suggest a suitable anti-oxidant therapy to prevent possible tissue injury.


Assuntos
Antioxidantes/metabolismo , Hanseníase/sangue , Mycobacterium leprae/crescimento & desenvolvimento , Estresse Oxidativo/fisiologia , Catalase/sangue , Glutationa/sangue , Humanos , L-Lactato Desidrogenase/sangue , Hanseníase/enzimologia , Peróxidos Lipídicos/sangue , Superóxido Dismutase/sangue
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