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1.
J Invest Surg ; 34(9): 935-946, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32003261

RESUMO

OBJECTIVE: To investigate the protective effect and underlying mechanisms of B. monnieri, a medicinal plant, on kidney and skeletal muscle injury induced by infra-renal abdominal aorta clamping for 2-hours (ischemia) and following removal of the clamp (reperfusion, 2-hours). METHODS: Rats were divided into four groups (n = 6): (I) animals given only saline (sham-control); (II) animals given B. monnieri extract for 10-days (300 mg/kg/day) (Bacopa-treated sham); (III) animals subjected to ischemia/reperfusion (I/R); (IV) animals given B. monnieri extract and then subjected to I/R. Kidneys and lower extremity muscles were examined for GPx, CAT, iNOS, 3-NT, IL-1ß and TNF-α. Apoptosis and injury were evaluated by TUNEL and H&E staining, respectively. RESULTS: I/R resulted in TUNEL positive cells, periarterial edema and glomerular capillary dilatation, decreased GPx activity, unchanged CAT, iNOS, 3-NT, IL-1ß and TNF-α in kidney. B. monnieri minimized renal remote reperfusion injury, and Group IV showed a lower degree of renal histopathology score when compared to the others. B. monnieri mitigated muscle I/R injury, decreased muscle hypertrophy, myofibril abnormalities and apoptosis. Muscle 3-NT and cytokine levels were increased by I/R, and B. monnieri inhibited iNOS and 3-NT both in sham-control and I/R groups. Muscle GPx unaffected by I/R or B. monnieri, but CAT was inhibited only in B. monnieri-treated I/R group. Muscle iNOS, 3-NT, IL-1ß, TNF-α levels and CAT activity of B. monnieri-treated I/R rats were lower than those in sham-control or Bacopa-treated sham. CONCLUSIONS: B. monnieri can protect the directly affected organ as well as distant organs against I/R injury by modulating anti-inflammatory and anti-nitrosative pathways.


Assuntos
Bacopa , Traumatismo por Reperfusão , Animais , Anti-Inflamatórios/uso terapêutico , Rim , Ratos , Ratos Wistar , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle
2.
Ocul Immunol Inflamm ; 28(6): 888-897, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31429629

RESUMO

INTRODUCTION: It was aimed to evaluate the efficacy of two tea tree oil (TTO)-based cleansing gels in chronic blepharitis patients. METHODS: Group-1 (basic gel containing 3%(w/w)-TTO) included 50 eyes of 25 patients and group-2 (advanced gel containing 3%(w/w)-TTO plus essential oils and vitamins) included 48 eyes of 24 patients. Ocular Surface Disease Index (OSDI), tear breakup time (TBUT), ocular surface staining pattern, Schirmer's test, impression cytology, Demodex presence and TNF-α, IL-6, IL-1ß levels were evaluated at the first visit and 1 month after treatment. RESULTS: In both groups, the mean OSDI score decreased (p1:0.001, p2:0.001), TBUT increased (p1:0.002, p2:0.004). In group-1, Demodex presence decreased from 42% to 27.8%; in group-2 from 54.2% to 20.6% (p1:0.302, p2:0.004). IL-1ß and IL-6 decreased in group-2 (p1:0.002, p2:0.050). TNF-α decreased in both groups (p1:0.001, p2:0.001). CONCLUSION: Both formulations improved ocular surface parameters. Group 2 showed more reduction in tear cytokines and Demodex count.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Blefarite/tratamento farmacológico , Óleo de Melaleuca/uso terapêutico , Adulto , Animais , Anti-Infecciosos Locais/efeitos adversos , Blefarite/metabolismo , Blefarite/parasitologia , Doença Crônica , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Proteínas do Olho/metabolismo , Pestanas/parasitologia , Feminino , Géis , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Ácaros , Preparações Farmacêuticas , Óleo de Melaleuca/efeitos adversos , Lágrimas/metabolismo , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo
3.
J Diet Suppl ; 13(3): 339-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26317558

RESUMO

This study investigated the effects of flaxseed (Linum usitatissimum L.) intake on general metabolism, pentose phosphate pathway (PPP) and glutathione-dependent enzymes in diabetic rats. Diabetes was induced by streptozotocin injection (40 mg/kg, i.p.) and the enzyme activities were determined spectrophotometrically. Diabetic and control rats were divided in two subgroups, one untreated, and one treated with flaxseed (0.714 g/kg body weight/day; orally) for 12 weeks. Flaxseed ameliorated decreased body weight (p < .05) and increased blood glucose (p < .001), triglyceride (p < .001), ALT (p < .001) and AST (p < .001) in diabetic rats. Diabetes resulted in increased glucose-6-phosphate dehydrogenase (G6PD) (p < .05) and decreased glutathione-S-transferase (GST) (p < .01), but unchanged 6-phosphogluconate dehydrogenase (6PGD) and glutathione reductase (GR) in the brain of rats. These alterations were partially improved by flaxseed in comparison to diabetic untreated group (p < .05). G6PD, 6PGD, GR were elevated (p < .001), while GST unchanged in the lung of diabetic untreated group compared to control. Flaxseed partially prevented the increase in 6PGD (p < .05) and GR (p < .01), but unaffected G6PD in the lung of diabetic rats. G6PD (p < .001), 6PGD (p < .05), GR (p < .001) were augmented, while GST showed a significant (p < .001) depletion in the pancreas of diabetic untreated rats compared to control. Diabetic alterations observed in pancreatic enzyme activities were significantly prevented by flaxseed. Furthermore, a remarkable decrease in 6PGD (p < .001) and an increase in G6PD (threefold of control) were found in the lens of diabetic untreated group that were completely prevented by flaxseed (p < .001). Flaxseed has beneficial effects against diabetes-induced glucotoxicity by modulating G6PD, 6PGD, GR and GST activities in tissues.


Assuntos
Antioxidantes , Glicemia/metabolismo , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Experimental/metabolismo , Linho , Glutationa/metabolismo , Via de Pentose Fosfato/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Peso Corporal/efeitos dos fármacos , Complicações do Diabetes/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Feminino , Glucosefosfato Desidrogenase/metabolismo , Glutationa Redutase/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Fosfogluconato Desidrogenase/metabolismo , Preparações de Plantas/farmacologia , Preparações de Plantas/uso terapêutico , Ratos Wistar , Sementes , Transaminases/sangue , Triglicerídeos/sangue
4.
Planta Med ; 80(12): 984-92, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25098929

RESUMO

Olive (Olea europaea) leaf, an important traditional herbal medicine, displays cardioprotection that may be related to the cellular redox modulating effects of its polyphenolic constituents. This study was undertaken to investigate the protective effect of the ethanolic and methanolic extracts of olive leaves compared to the effects of oleuropein, hydroxytyrosol, and quercetin as a positive standard in a carbonyl compound (4-hydroxynonenal)-induced model of oxidative damage to rat cardiomyocytes (H9c2). Cell viability was detected by the MTT assay; reactive oxygen species production was assessed by the 2',7'-dichlorodihydrofluorescein diacetate method, and the mitochondrial membrane potential was determined using a JC-1 dye kit. Phospho-Hsp27 (Ser82), phospho-MAPKAPK-2 (Thr334), phospho-c-Jun (Ser73), cleaved-caspase-3 (cl-CASP3) (Asp175), and phospho-SAPK/JNK (Thr183/Tyr185) were measured by Western blotting. The ethanolic and methanolic extracts of olive leaves inhibited 4-hydroxynonenal-induced apoptosis, characterized by increased reactive oxygen species production, impaired viability (LD50: 25 µM), mitochondrial dysfunction, and activation of pro-apoptotic cl-CASP3. The ethanolic and methanolic extracts of olive leaves also inhibited 4-hydroxynonenal-induced phosphorylation of stress-activated transcription factors, and the effects of extracts on p-SAPK/JNK, p-Hsp27, and p-MAPKAPK-2 were found to be concentration-dependent and comparable with oleuropein, hydroxytyrosol, and quercetin. While the methanolic extract downregulated 4-hydroxynonenal-induced p-MAPKAPK-2 and p-c-Jun more than the ethanolic extract, it exerted a less inhibitory effect than the ethanolic extract on 4-hydroxynonenal-induced p-SAPK/JNK and p-Hsp27. cl-CASP3 and p-Hsp27 were attenuated, especially by quercetin. Experiments showed a predominant reactive oxygen species inhibitory and mitochondrial protecting ability at a concentration of 1-10 µg/mL of each extract, oleuropein, hydroxytyrosol, and quercetin. The ethanolic extract of olive leaves, which contains larger amounts of oleuropein, hydroxytyrosol, verbascoside, luteolin, and quercetin (by HPLC) than the methanolic one, has more protecting ability on cardiomyocyte viability than the methanolic extract or each phenolic compound against 4-hydroxynonenal-induced carbonyl stress and toxicity.


Assuntos
Antioxidantes/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Olea/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Aldeídos , Animais , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Técnicas In Vitro , Glucosídeos Iridoides , Iridoides/farmacologia , Mitocôndrias/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/farmacologia , Folhas de Planta/química , Substâncias Protetoras/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Quercetina/farmacologia , Ratos , Fatores de Transcrição/metabolismo
5.
Int J Vitam Nutr Res ; 84(5-6): 295-309, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26255551

RESUMO

Current evidence has demonstrated the immunomodulatory efficacy of omega-3 polyunsaturated fatty acids (PUFAs) in glial cells, suggesting their therapeutic potential for diseases in the central nervous system (CNS). However, conjugated omega-5 PUFAs have also attracted considerable attention because of their suggested anti-inflammatory effects. In the present study, the effect of pomegranate (Punica granatum L.) seed oil (PSEO) (a rich source of omega-5 PUFAs) on the activation of cultured BV-2 microglia was investigated within a 24-hour incubation period. PSEO (25 µg/ml) showed only a slightly smaller inhibitory effect on LPS-stimulated NO production (243 ± 12.5 % of control, p<0.001 vs. 437 ± 9.2 % in stimulated cells) and TNF-α release (87.1 ± 5.62 pg/ml vs. 229 ± 24.4 pg/ml in stimulated cells), as well as iNOS expression (7.36-fold of control, p < 0.01, vs. 17.5-fold increase in stimulated cells) compared to a standardized omega-3 PUFAs mixture (25 µg/ml) and the flavonoid quercetin (25 µmol/l). Unlike quercetin and stobadine, only the PUFA preparations effectively prevented apoptosis of microglia (as confirmed by the suppression of caspase 3 activation) exposed to the toxic concentration of LPS. The PUFA preparations did not provide a notable suppression of the intracellular oxidant generation and did not influence the intracellular distribution of cholesterol (as confirmed by filipin staining). However, they appeared to affect the morphology of activated cells. In conclusion, our data point to the first evidence of immunomodulation and cytoprotection of BV-2 microglia by the pomegranate seed oil, indicating that it may be (comparably to omega-3 PUFAs) efficient against microglia-mediated neuroinflammation while preventing the premature depletion of these immune effector cells in the brain.


Assuntos
Lythraceae/química , Microglia/citologia , Microglia/efeitos dos fármacos , Óleos de Plantas/farmacologia , Sementes/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Ácidos Graxos Ômega-3/farmacologia , Regulação da Expressão Gênica/fisiologia , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
6.
Interdiscip Toxicol ; 5(1): 15-20, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22783144

RESUMO

The pomegranate, Punica granatum L., has been the subject of current interest as a medicinal agent with wide-ranging therapeutic indications. In the present study, pomegranate ethanolic seed and hull extracts were tested, in comparison with a commercial sample, for the inhibition of aldose reductase, an enzyme involved in the etiology of diabetic complications. In vitro inhibition of rat lens aldose reductase was determined by a conventional method. Pomegranate ethanolic hull extract and commercial pomegranate hull extract exhibited similar aldose reductase inhibitory activity characterized by IC(50) values ranging from 3 to 33.3 µg/ml. They were more effective than pomegranate ethanolic seed extract with IC(50) ranging from 33.3 to 333 µg/ml. Antioxidant action of the novel compounds was documented in a DPPH test and in a liposomal membrane model, oxidatively stressed by peroxyl radicals. All the plant extracts showed considerable antioxidant potential in the DPPH assay. Pomegranate ethanolic hull extract and commercial pomegranate hull extract executed similar protective effects on peroxidatively damaged liposomal membranes characterized by 10

7.
Rejuvenation Res ; 14(3): 325-34, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21745095

RESUMO

Various pancreatic ß-cell stressors, including cytokines, are known to induce oxidative stress, resulting in apoptotic/necrotic cell death and inhibition of insulin secretion. Traditionally, olive leaves or fruits are used for treating diabetes, but the cellular mechanism(s) of their effects are not known. We examined the effects of Olea europea L. (olive) leaf and fruit extracts and their component oleuropein on cytokine-induced ß-cell toxicity. INS-1, an insulin-producing ß-cell line, was preincubated with or without increasing concentrations of olive leaf or fruit extract or oleuropein for 24 hr followed by exposure to a cytokine cocktail containing 0.15 ng/mL interleukin-1ß (IL-1ß), 1 ng/mL interferon-γ (IFN-γ), and 1 ng/mL tumor necrosis factor-α (TNF-α) for 6 hr. The cytotoxicity was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) testing. Apoptosis was quantified by detecting acridine orange/ethidium bromide-stained condensed nuclei under a fluorescent microscope. The cells exposed to cytokines had a higher apoptotic rate, a decreased viability (MTT), and an increased caspase 3/7 activity. Both extracts and oleuropein partially increased the proportion of living cells and improved the viability of cells after cytokines. The protective effects of extracts on live cell viability were mediated through the suppression of caspase 3/7 activity. Oleuropein did not decrease the amount of both apoptotic and necrotic cells, whereas extracts significantly protected cells against cytokine-induced death. Cytokines led to an increase in reactive oxygen species (ROS) generation and inhibited glutathione level, superoxide dismutase activity, and insulin secretion in INS-1. Insulin secretion was almost completely protected by leaf extract, but was partially affected by fruit extract or oleuropein. Neither cytokines nor olive derivatives had a significant effect on cellular cytochrome c release and catalase activity. Moreover, the cells incubated with each extract or oleuropein showed a significant reduction in cytokine-induced ROS production and ameliorated abnormal antioxidant defense. The molecular mechanism by which olive polyphenols inhibit cytokine-mediated ß-cell toxicity appears to be involving the maintenance of redox homeostasis.


Assuntos
Citocinas/farmacologia , Citoproteção/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Células Secretoras de Insulina/patologia , Olea/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Animais , Caspase 3/metabolismo , Caspase 7/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Citocromos c/metabolismo , Glutationa/metabolismo , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/enzimologia , Células Secretoras de Insulina/metabolismo , Glucosídeos Iridoides , Iridoides , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução/efeitos dos fármacos , Piranos/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
8.
Med Chem ; 7(6): 711-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22313311

RESUMO

The potential protective effect of (±)-8-methoxy-1,3,4,4a,5,9b-hexahydro-pyrido[4,3-b]indole-2-carboxylic acid ethyl ester (II) was assessed against hydrogen peroxide (H2O2)-cytotoxicity in rat pancreatic INS-1E ß cells and compared with the effect of the related pyridoindole, stobadine (I), a promising indole-type reference antioxidant. Only pre-treatment with the compound (II) led to a significant preservation of the metabolic and secretory functions of the cells exposed to H2O2. The caspase-9 and -3 activities, as well as the early apoptotic changes of plasma membrane, were suppressed in the cells pre-incubated with both of compounds tested. However, only pyridoindole (II) inhibited profoundly the time-delayed apoptotic changes, These results suggest that pyridoindole (II) characterized by enhanced intrinsic antioxidant efficiency, may protect ß cells against cytotoxic effects of H2O2, involved in the development of both type 1 and type 2 diabetes.


Assuntos
Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/síntese química , Antioxidantes/química , Apoptose/efeitos dos fármacos , Inibidores de Caspase , Caspases/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/farmacologia , Indóis/síntese química , Indóis/química , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Estrutura Molecular , Ratos , Relação Estrutura-Atividade
9.
Bioorg Med Chem ; 16(9): 4908-20, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18395454

RESUMO

Starting from the efficient hexahydropyridoindole antioxidant stobadine, a series of carboxymethylated tetrahydro- and hexahydropyridoindole derivatives was synthesized and tested for the inhibition of aldose reductase, an enzyme involved in the etiology of diabetic complications. In vitro inhibiton of rat lens aldose reductase was determined by a conventional method. Kinetic analysis of (2-benzyl-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole-8-yl)-acetic acid (5b) and (2-phenethyl-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole-8-yl)-acetic acid (5c), the most potent compounds in this series with activities in micromolar range, showed uncompetitive inhibition. In addition to the importance of the acidic function, the inhibition efficacy was highly influenced by the steric conformation of the lipophilic aromatic backbone when comparing tetrahydro- and hexahydropyridoindole congeners. Selectivity with respect to the closely related aldehyde reductase was determined by measuring the corresponding inhibitory activities. Antioxidant action of the novel compounds was documented in a DPPH test and in a liposomal membrane model, oxidatively stressed by peroxyl radicals. The presence of a basicity center at the tertiary nitrogen, in addition to the acidic carboxylic function, predisposes these compounds to form double charged zwitterionic species, a characteristic which may remarkably affect their pH-lipophilicity profile. For compounds 5b and 5c, a maximal distribution ratio in a system comprised of 1-octanol/phosphate buffer was recorded near the neutral physiological pH, the region where the isoelectric point lies. Molecular docking simulations into the ALR2 active site performed for the zwitterionic species provided an explanation for the observed structure-activity relationships and the calculated parameters were in agreement with characteristic differences in the stereoelectronic profiles of the tetrahydro- versus hexahydropyridoindoles. 'Drug-likeness' of the novel aldose reductase inhibitors was assessed by applying the criteria of Lipinski's 'rule of five'.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Antioxidantes , Carbolinas , Inibidores Enzimáticos , Aldeído Redutase/química , Animais , Antioxidantes/síntese química , Antioxidantes/química , Antioxidantes/farmacologia , Carbolinas/síntese química , Carbolinas/química , Carbolinas/farmacologia , Simulação por Computador , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Concentração de Íons de Hidrogênio , Cinética , Masculino , Metilação , Modelos Moleculares , Estrutura Molecular , Ratos , Ratos Wistar , Eletricidade Estática , Estereoisomerismo , Relação Estrutura-Atividade , Fatores de Tempo
10.
J Pharm Pharmacol ; 59(12): 1629-41, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18053324

RESUMO

Abnormalities in the metabolism of essential fatty acids and the results of increased oxidative stress have been implicated in cardiovascular disorders observed in diabetes mellitus. This study, therefore, aimed to investigate the effects of cod liver oil (CLO, Lysi Ltd, Iceland), which comprises mainly an antioxidant vitamin A, n:3 polyunsaturated fatty acids (n:3 PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on cardiovascular abnormalities in streptozotocin (STZ)-diabetic rats. Two days after single STZ (55 mg kg(-1), i.p.) or vehicle injection, diabetes was verified by increased blood glucose, and non-diabetic and diabetic rats were left untreated or treated with CLO (0.5 mL kg(-1) daily, by intragastric probing) for 12 weeks. Plasma glucose, triacylglycerol and cholesterol concentrations were significantly elevated in 12-week untreated-diabetic rats; CLO provided better weight gain, entirely prevented the plasma lipid abnormalities, but partially controlled the glycaemia in diabetic rats. In isolated aorta rings, diabetes resulted in increased phenylephrine-induced vasoconstriction and isoprenaline-induced vasorelaxation, impaired endothelium-dependent vasodilatation and unchanged responsiveness to sodium nitroprusside. CLO treatment completely prevented endothelial deficiency, partly corrected the phenylephrine-induced vasoconstriction and did not affect the responses to isoprenaline and sodium nitroprusside in diabetic aorta. Diabetes also produced a marked decrease in the rate of spontaneously beating right atria and a significant increase in basal contractile force of left ventricular papillary muscle. The responsiveness of right atria to the positive chronotropic effect of isoprenaline was significantly decreased in diabetic rats, and was increased in CLO-treated diabetic rats. The positive chronotropic effect of noradrenaline was markedly increased in diabetic atria, but prevented by CLO treatment. Diabetes also resulted in an increased positive inotropic response of papillary muscle to both noradrenaline and isoprenaline, which were prevented by CLO treatment. CLO treatment also resulted in lower tissue sensitivity (pD(2)) to these agonists in diabetic papillary muscle. Ventricular hydroxyproline content was found to be unchanged among the experimental groups. The ultrastructure of diabetic myocardium displayed various degenerations (i.e. intracellular oedema, myofibrillar fragmentation, condensed pleomorphic mitochondria, thick capillary irregular basement membrane, swollen endothelial cells), which were partially prevented by CLO treatment. We conclude that the supplementation with CLO is effective in preventing cardiovascular disorders observed in experimental diabetes.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Óleo de Fígado de Bacalhau/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Suplementos Nutricionais , Doenças Metabólicas/tratamento farmacológico , Acetilcolina/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Glicemia/metabolismo , Doenças Cardiovasculares/fisiopatologia , Óleo de Fígado de Bacalhau/administração & dosagem , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/fisiopatologia , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Coração/efeitos dos fármacos , Coração/fisiopatologia , Hidroxiprolina/metabolismo , Técnicas In Vitro , Isoproterenol/farmacologia , Lipídeos/sangue , Masculino , Doenças Metabólicas/fisiopatologia , Microscopia Eletrônica , Miocárdio/metabolismo , Miocárdio/patologia , Miocárdio/ultraestrutura , Nitroprussiato/farmacologia , Norepinefrina/farmacologia , Fenilefrina/farmacologia , Ratos , Ratos Wistar , Estreptozocina/toxicidade , Vasoconstrição/efeitos dos fármacos
11.
Mol Vis ; 11: 56-65, 2005 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-15682043

RESUMO

PURPOSE: The aim of this study was to investigate the effect of dietary supplementation with the pyridoindole antioxidant stobadine on the development of diabetic cataract in rats. The findings were compared with the effect of the natural antioxidant vitamin E and the well known phenolic synthetic antioxidant butylated hydroxytoluene. METHODS: Streptozotocin induced diabetic male Wistars rats were fed for 18 weeks a standard diet or a diet supplemented with stobadine (0.05% w/w), vitamin E (0.1% w/w), butylated hydroxytoluene (BHT, 0.4% w/w), or a mixture of stobadine (0.05% w/w) and vitamin E (0.1% w/w). The progress of cataract was monitored biweekly by ophthalmoscopic inspection. Plasma glucose and body weight were recorded regularly. At the end of the experiment, the content of free sulfhydryl and carbonyl was determined in total lens proteins and in the stobadine group plasma levels of malondialdehyde were also measured. RESULTS: Long term treatment of diabetic animals with stobadine (STB), vitamin E, or BHT led to a marked delay in the development of advanced stages of cataract. At the end of the experiment, the visual cataract score was significantly decreased in the diabetic groups treated with stobadine or BHT, while vitamin E had no significant effect. Unexpectedly, combined treatment with STB+vitamin E advanced the progression of the higher stages of cataract, though without affecting the overall visual cataract score. Neither of the antioxidants exerted an effect on the glycemic state or body weight of the animals. Biochemical analyses of eye lens proteins showed significant diminution of sulfhydryl groups and elevation of carbonyl groups in diabetic animals in comparison to healthy controls. Dietary supplementation with any of the antioxidants studied did not influence the levels of these biomarkers significantly. Nevertheless, in diabetic animals, stobadine supplementation significantly attenuated plasma levels of malondialdehyde, an index of systemic oxidative damage. CONCLUSIONS: The results are in accordance with the postulated pro-oxidant role of chronic hyperglycemia, however, the direct oxidative free radical damage of eye lens proteins does not seem to be the key mechanism effective in the development of diabetic cataract. Sugar cataractogenesis appears to be a complex process, in which multiple mechanisms may be involved, including consequences of the overt oxidative stress in diabetes (e.g., protein modifying potential of toxic aldehydes generated as byproducts of carbohydrate autoxidation and lipid peroxidation). The ability of stobadine to attenuate lipoxidation reactions in diabetes may account, at least partly, for its observed anticataract action. Mechanisms involving reduction of mitochondrial damage by stobadine are also discussed.


Assuntos
Antioxidantes/administração & dosagem , Hidroxitolueno Butilado/metabolismo , Carbolinas/administração & dosagem , Catarata/metabolismo , Cristalinas/metabolismo , Diabetes Mellitus Experimental/metabolismo , Vitamina E/metabolismo , Animais , Glicemia/metabolismo , Peso Corporal , Catarata/fisiopatologia , Diabetes Mellitus Experimental/fisiopatologia , Suplementos Nutricionais , Progressão da Doença , Combinação de Medicamentos , Cristalino/metabolismo , Cristalino/fisiopatologia , Masculino , Malondialdeído/sangue , Oxirredução , Ratos , Ratos Wistar
12.
Cell Biochem Funct ; 21(2): 177-82, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12736908

RESUMO

Vitamin E treatment has been found to be beneficial in preventing or reducing diabetic nephropathy. Increased tissue calcium and abnormal microsomal Ca(2+)-ATPase activity have been suggested as contributing factors in the development of diabetic nephropathy. This study was undertaken to test the hypothesis that vitamin E reduces lipid peroxidation and can prevent the abnormalities in microsomal Ca(2+)-ATPase activity and calcium levels in kidney of streptozotocin (STZ)-induced diabetic rats. Male rats were rendered diabetic by a single STZ injection (55 mg x kg(-1) i.p.). After diabetes was verified, diabetic and age-matched control rats were untreated or treated with vitamin E (400-500 IU kg(-1) x day(-1), orally) for 10 weeks. Ca(2+)-ATPase activity and lipid peroxidation (MDA) were determined spectrophotometrically. Blood glucose levels increased approximately five-fold (> 500 mg x dl(-1)) in untreated-diabetic rats but decreased to 340+/-27 mg x dl(-1) in the vitamin E treated-diabetic group. Kidney MDA levels did not significantly change in the diabetic state. However, vitamin E treatment markedly inhibited MDA levels in both control and diabetic animals. Ca(2+)-ATPase activity was 0.483+/-0.008 U l(-1) in the control group and significantly increased to 0.754+/-0.010 U l(-1) in the STZ-diabetic group (p < 0.001). Vitamin E treatment completely prevented the diabetes-induced increase in Ca(2+)-ATPase activity (0.307+/-0.025 U l(-1), p < 0.001) and also reduced the enzyme activity in normal control rats. STZ-diabetes resulted in approximately two-fold increase in total calcium content of kidney. Vitamin E treatment led to a significant reduction in kidney calcium levels of both control and diabetic animals (p < 0.001). Thus, vitamin E treatment can lower blood glucose and lipid peroxidation, which in turn prevents the abnormalities in kidney calcium metabolism of diabetic rats. This study describes a potential biochemical mechanism by which vitamin E supplementation may delay or inhibit the development of cellular damage and nephropathy in diabetes.


Assuntos
Antioxidantes/farmacologia , ATPases Transportadoras de Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Vitamina E/farmacologia , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Microssomos/efeitos dos fármacos , Ratos , Ratos Wistar
13.
Cell Biochem Funct ; 20(4): 297-302, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12415563

RESUMO

Lipid disorders and increased oxidative stress may exacerbate some complications of diabetes mellitus. Previous studies have implicated the beneficial effects of some antioxidants, omega-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the protection of cells from the destructive effect of increased lipids and lipid peroxidation products. This study, therefore, was designed to investigate the effects of cod liver oil (CLO, Lysi Ltd. Island), which comprises mainly vitamin A, PUFAs, EPA and DHA. Effects were monitored on plasma lipids, lipid peroxidation products (MDA) and the activities of antioxidant enzymes, glutathione peroxidase (GSHPx) and catalase in heart, liver, kidney and lung of non-diabetic control and streptozotocin (STZ)-induced-diabetic rats. Two days after STZ-injection (55 mg kg(-1) i.p.), non-diabetic control and diabetic rats were divided randomly into two groups as untreated or treated with CLO (0.5 ml kg(-1) rat per day) for 12 weeks. Plasma glucose, triacylglycerol and cholesterol concentrations were significantly elevated in 12-week untreated-diabetic animals; CLO treatment almost completely prevented these abnormalities in triacylglycerol and cholesterol, but hyperglycaemia was partially controlled. CLO also provided better weight gain in diabetic animals. In untreated diabetic rats, MDA markedly increased in aorta, heart and liver but was not significantly changed in kidney and lung. This was accompanied by a significant increase in both GSHPx and catalase enzyme activities in aorta, heart, and liver of diabetic rats. In kidney and lung, diabetes resulted in reduced catalase while GSHPx was significantly activated. In aorta, heart, and liver, diabetes-induced changes in MDA were entirely prevented by CLO treatment. In the tissues of CLO-treated diabetic animals, GSHPx activity paralleled those of control animals. CLO treatment also caused significant improvements in catalase activities in every tissue of diabetic rats, but failed to affect MDA and antioxidant activity in control animals. The current study suggests that the treatment of diabetic rats with CLO provides better control of glucose and lipid metabolism, allows recovery of normal growth rate, prevents oxidative/peroxidative stress and ameliorates endogenous antioxidant enzyme activities in various tissues. Because CLO contains a plethora of beneficial compounds together, its use for the management of diabetes-induced complications may provide important advantages.


Assuntos
Antioxidantes/farmacologia , Óleo de Fígado de Bacalhau/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Colesterol/sangue , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Estreptozocina , Fatores de Tempo , Triglicerídeos/sangue
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