RESUMO
Nonalcoholic steatohepatitis (NASH) is a disease with a high incidence worldwide, but its diagnosis and treatment are poorly managed. In this study, NASH pathophysiology and DNA damage biomarkers were investigated in mice with NASH treated and untreated with melatonin (MLT). C57BL/6 mice were fed a methionine- and choline-deficient (MCD) diet for 4 weeks to develop NASH. Melatonin was administered at 20 mg/kg during the last 2 weeks. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were measured, and hepatic tissue was dissected for histological analysis, evaluation of lipoperoxidation, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as nuclear factor-erythroid 2 (Nrf2), tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS), and transforming growth factor beta (TGF-ß) expression by immunohistochemistry. DNA damage was evaluated using Comet assay, while a micronucleus test in bone marrow was performed to assess the genomic instability associated with the disease. Melatonin decreased AST and ALT, liver inflammatory processes, balloonization, and fibrosis in mice with NASH, decreasing TNF-α, iNOS, and TGF-ß, as well as oxidative stress, shown by reducing lipoperoxidation and intensifying Nrf2 expression. The SOD and GPx activities were increased, while CAT was decreased by treatment with MLT. Although the micronucleus frequency was not increased in mice with NASH, a protective effect on DNA was observed with MLT treatment in blood and liver tissues using Comet assay. As conclusions, MLT slows down the progression of NASH, reducing hepatic oxidative stress and inflammatory processes, inhibiting DNA damage via anti-inflammatory and antioxidant actions.
Assuntos
Deficiência de Colina , Melatonina , Hepatopatia Gordurosa não Alcoólica , Alanina Transaminase , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Aspartato Aminotransferases , Biomarcadores/metabolismo , Catalase/metabolismo , Colina/análise , Colina/metabolismo , Colina/farmacologia , Deficiência de Colina/complicações , Deficiência de Colina/metabolismo , Dano ao DNA , Dieta , Glutationa Peroxidase/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Melatonina/farmacologia , Melatonina/uso terapêutico , Metionina/análise , Metionina/genética , Metionina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The avulsion of nerve roots of the brachial plexus that is commonly seen in motorcycle accidents is a type of neuropathy due to deafferentation. This type of pain is clinically challenging since therapeutical protocols fail or have severe side effects. Thus, it is proposed to evaluate the antinociceptive activity of the recombinant CTK 01512-2 peptide that is derived from the venom of the Phoneutria nigriventer spider, as a future new therapeutical option. The neuropathic pain was surgically induced by avulsion of the upper brachial plexus trunk in groups of male Wistar rats and after 17â¯days, they were treated intrathecally with morphine, ziconotide, and CTK 01512-2. Behavioral tests were performed to evaluate mechanical and thermal hyperalgesia, cold allodynia, the functional activity of the front paw, and exploratory locomotion after the treatments. The peripheral blood samples were collected 6â¯h after the treatments and a comet assay was performed. The spinal cord was removed for the lipoperoxidation dosing of the membranes. The cerebrospinal fluid was analyzed for the dosage of glutamate. The recombinant peptide showed an antinociceptive effect when compared to the other drugs, without affecting the locomotor activity of the animals. Mechanical and thermal hyperalgesia, as well as cold allodynia, were reduced in the first hours of treatment. The levels of glutamate and the damage by membrane lipoperoxidation were shown to be improved, and genotoxicity was not demonstrated. In a scenario of therapeutical failures in the treatment of this type of pain, CTK 01512-2 was shown as a new effective alternative protocol. However, further testing is required to determine pharmacokinetics.
Assuntos
Analgésicos/farmacologia , Aranhas/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Peçonhas/metabolismo , Animais , Diferenciação Celular , Masculino , Morfina/farmacologia , Nociceptividade/efeitos dos fármacos , Peptídeos/farmacologia , Ratos Wistar , Aranhas/metabolismo , Medula Espinal/citologiaRESUMO
The use of natural products from herbs may be a therapeutic option in dyslipidemia treatment. Campomanesia xanthocarpa (Mart.) O. Berg (Myrtaceae) leaves have been used to decrease cholesterol levels. However, studies to determine activities of this plant on triglycerides metabolism have received little attention. The aim of this study was to examine anti-hyperlipidemic effects of a C. xanthocarpa aqueous leaf extract (CxAE) and assess protective actions against oxidative stress and DNA damage. The tyloxapol-induced hyperlipidemia model was used in Wistar rats. Rats were treated orally with CxAE either 250 or 500 mg/kg/day for 7 days prior to tyloxapol administration. Biochemical parameters, oxidative stress levels, and genomic instability were assessed in several tissues. CxAE decreased cholesterol and triglyceride levels in serum and hepatic and renal DNA damage in tyloxapol-treated rats. There was no marked effect on the micronucleus frequency in bone marrow. The extract increased catalase activity and decreased glutathione S-transferase activity in kidney tissue. CxAE showed anti-hyperlipidemic effects, improved oxidative parameters, and protected DNA against damage induced by tyloxapol-induced hyperlipidemia, suggesting C. xanthocarpa leaves may be useful in preventing dyslipidemias.Abbreviations: ALP: Alkaline phosphatase; ALT: Aspartate aminotransferase; ANOVA: Analysis of variance; AST: Aspartate aminotransferase; Ator: Atorvastatin; CAT: Catalase; Chol: Cholesterol; CxAE: Campomanesia xanthocarpa aqueous extract; GST: Glutathione S-transferase; HDL: High density cholesterol; i.p.: Intraperitoneal; NCE: Normochromatic erythrocyte; PBS: Phosphate buffer solution; PCE: Polychromatic erythrocyte; ROS: Reactive oxygen species; SD: Standard deviation; SOD: Superoxide dismutase; T: Tyloxapol; TBARS: Thiobarbituric acid reacting substances; TG: Triglyceride.
Assuntos
Dano ao DNA/efeitos dos fármacos , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Myrtaceae/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/toxicidade , Extratos Vegetais/uso terapêutico , Animais , Folhas de Planta/química , Ratos , Ratos WistarRESUMO
OBJECTIVE: In this study, we evaluated the efficacy of simvastatin in the treatment of nonalcoholic steatohepatitis induced by methionine and choline-deficient diet in mice and its possible effect on factors involved in the pathogenesis of the disease including oxidative stress and endoplasmic reticulum stress. METHOD: Male C57BL6 mice were fed either a normal diet (control) or a methionine and choline-deficient diet for four weeks and then treated orally with simvastatin (4 mg/kg once a day) for two final weeks. At the end of the experimental period, liver integrity, biochemical analysis, hepatic lipids, histology, DNA damage, biomarkers of oxidative stress, and endoplasmic reticulum stress were assessed. RESULTS: Simvastatin treatment was able to significantly reduce hepatic damage enzymes and hepatic lipids and lower the degree of hepatocellular ballooning, without showing genotoxic effects. Simvastatin caused significant decreases in lipid peroxidation, with some changes in antioxidant enzymes superoxide dismutase and glutathione peroxidase. Simvastatin activates antioxidant enzymes via Nrf2 and inhibits endoplasmic reticulum stress in the liver. CONCLUSIONS: In summary, the results provide evidence that in mice with experimental nonalcoholic steatohepatitis induced by a methionine and choline-deficient diet, the reduction of liver damage by simvastatin is associated with attenuated oxidative and endoplasmic reticulum stress.
Assuntos
Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sinvastatina/uso terapêutico , Animais , Antioxidantes/metabolismo , Deficiência de Colina/complicações , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Inflamação/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Metionina/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismoRESUMO
OBJECTIVE: To evaluate the pulmonary alterations of animals with Hepatopulmonary Syndrome (HPS) submitted to Biliary Duct Ligature (BDL), as well as the antioxidant effect of Melatonin (MEL). METHODS: Sixteen male Wistar rats, divided into four Sham groups: BDL group, Sham + MEL group and BDL + MEL. The pulmonary and hepatic histology, lipoperoxidation and antioxidant activity of lung tissue, alveolar-arterial O2 difference and lung / body weight ratio (%) were evaluated. RESULTS: When comparing the groups, could be observed an increase of vasodilation and pulmonary fibrosis in the BDL group and the reduction of this in relation to the BDL + MEL group. It was also observed significant changes in the activity of catalase, ApCO2, ApO2 in the LBD group when compared to the other groups. CONCLUSION: The use of MEL has been shown to be effective in reducing vasodilation, fibrosis levels and oxidative stress as well as gas exchange in an experimental HPS model.
Assuntos
Antioxidantes/farmacologia , Síndrome Hepatopulmonar/tratamento farmacológico , Pulmão/efeitos dos fármacos , Melatonina/farmacologia , Animais , Pressão Arterial/efeitos dos fármacos , Ductos Biliares/cirurgia , Gasometria , Catalase/análise , Modelos Animais de Doenças , Glutationa Transferase/análise , Síndrome Hepatopulmonar/patologia , Síndrome Hepatopulmonar/fisiopatologia , Ligadura , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Reprodutibilidade dos Testes , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Resultado do TratamentoRESUMO
Campomanesia xanthocarpa leaves are used as tea to treat diarrhea, inflammation, and hypercholesterolemia. Some pharmacological studies noted its beneficial uses of C. xanthocarpa; however, few investigations examined the toxicological profile of this plant. The aim of this study was to determine the chemical composition, genotoxic, and mutagenic potential of an aqueous extract of C. xanthocarpa leaves (CxAE), and potential protective effects against oxidative damage. Phytochemical constituents were determined using HPLC, and antioxidant effect in vitro was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. Genotoxic effects and chromosomic mutations were assessed using comet assay and micronucleus (MN) test in Wistar rats treated with CxAE at 250, 500 or 1000 mg/kg for 7 consecutive days. Lipid peroxidation and antioxidant enzyme activities were measured in several tissues. CxAE induced mutations in TA98, TA97a, and TA102 strains. However, in the presence of metabolic activation, data were negative for all strains tested. Lack of mutagenicity was also observed in the MN test. This extract did not induce DNA damage, except when the highest concentration was used. DNA oxidative damage induced by hydrogen peroxide (H2O2) decreased in blood after treatment with CxAE. Lipid peroxidation levels were reduced while superoxide dismutase (SOD) activity increased in kidneys. The inhibitory concentration of CxAE required to lower DPPH levels to 50% was 38.47 ± 2.06 µg/ml. In conclusion, frameshift and oxidative mutations were observed only in the absence of metabolic activation which may be attributed to the presence of flavonoids such as quercetin. It is of interest that CxAE also showed protective effects against DNA oxidative damage associated with presence of ellagic acid, a phenolic acid with antioxidant activities. CxAE did not induce in vivo mutagenicity, suggesting that this extract poses a low toxic hazard over the short term.
Assuntos
Myrtaceae/toxicidade , Estresse Oxidativo , Animais , Compostos de Bifenilo , Ensaio Cometa , Relação Dose-Resposta a Droga , Masculino , Testes para Micronúcleos , Myrtaceae/química , Picratos , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Folhas de Planta/química , Ratos , Ratos WistarRESUMO
In recent decades, the number of people who practice sports has grown exponentially, increasing the number of muscular injuries. Trauma injury occurs when the muscle is exposed to a sudden compression force. Melatonin (MLT) has often been cited in the literature as a potent antioxidant and anti-inflammatory agent. This study was designed to evaluate MLT action on muscle tissue in Wistar rats in an experimental model of muscle trauma. Twenty-eight Wistar rats were used, divided into four groups: CO (Control), COâ¯+â¯MLT (Controlâ¯+â¯Melatonin), T (Trauma) and Tâ¯+â¯MLT (Traumaâ¯+â¯Melatonin). MLT (20â¯mg/kg) was administered (ip) daily at dusk until day 7. The trauma occurred on day 1, 2â¯h before the first MLT application. On day 8, muscle tissue was collected for histological analysis (HE), immunohistochemistry (TNF-α and NFκB), evaluation of oxidative stress through analysis of lipoperoxidation by TBARS and activity of SOD and GPx enzymes, and analysis of nitrites and nitrates. In the evaluation of TBARS and SOD, we observed a significant increase in the T group and a significant decrease in the Tâ¯+â¯MLT group. In the evaluation of GPx, there was a significant increase in the T group and a significant decrease in the Tâ¯+â¯MLT group. The histological analysis of muscle tissue revealed structural changes of muscle fibers and inflammatory infiltrate in the T group but a decrease in this damage in the Tâ¯+â¯MLT group. In the immunohistochemical evaluation, increased expression of TNFα and NFκB proteins in the T group was observed and a significant decrease of this expression in the Tâ¯+â¯MLT group. MLT was shown to attenuate oxidative damage and to diminish the expression of inflammatory proteins and tissue damage in this experimental model.
Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Contusões/tratamento farmacológico , Melatonina/uso terapêutico , Músculo Quadríceps/lesões , Ferimentos não Penetrantes/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Contusões/patologia , Avaliação Pré-Clínica de Medicamentos , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Melatonina/farmacologia , Fibras Musculares Esqueléticas/patologia , NF-kappa B/biossíntese , Óxido Nítrico/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Músculo Quadríceps/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Ferimentos não Penetrantes/patologiaRESUMO
Rates of obesity have been growing at alarming rates, compromising the health of the world population. Thus, the search for interventions that address the metabolic repercussions of obesity are necessary. Here we evaluated the metabolic and antioxidant effects of zinc and branched-chain amino acids (BCAA) supplementation on obese rats. Male Wistar rats were fed either a high-fat/high-fructose diet (HFD) or a standard diet (SD) for 19 weeks. From the fifteenth week until the end of the experiment, HFD- and SD-fed rats received zinc (6 mg/kg) or BCAA (750 mg/kg) supplementation. Body weight, abdominal fat, lipid profile, blood glucose, insulin, leptin, and hepatic transaminases were evaluated. In the liver, superoxide dismutase and catalase activities and lipid peroxidation were also analyzed. HFD-fed animals showed increased weight gain, abdominal fat pad, plasma insulin, leptin, and triglycerides levels in comparison with SD-fed rats. Zinc supplementation reduced all these parameters, suggesting a beneficial role for the treatment of obesity. BCAA, on the other hand, did not show any beneficial effect. Liver antioxidant enzymes and hepatic transaminases plasma levels did not change among groups. Lipid peroxidation was higher in HFD-fed rats and was not reverted by zinc or BCAA supplementation. In conclusion, zinc supplementation may be a useful strategy for the treatment of the metabolic dysfunction associated with obesity.
Assuntos
Aminoácidos de Cadeia Ramificada/administração & dosagem , Antioxidantes/farmacologia , Resistência à Insulina , Obesidade/terapia , Zinco/administração & dosagem , Animais , Glicemia , Dieta Hiperlipídica , Suplementos Nutricionais , Insulina/sangue , Leptina/sangue , Peroxidação de Lipídeos , Lipídeos/sangue , Masculino , Distribuição Aleatória , Ratos WistarRESUMO
ABSTRACT Objective: To evaluate the pulmonary alterations of animals with Hepatopulmonary Syndrome (HPS) submitted to Biliary Duct Ligature (BDL), as well as the antioxidant effect of Melatonin (MEL). Methods: Sixteen male Wistar rats, divided into four Sham groups: BDL group, Sham + MEL group and BDL + MEL. The pulmonary and hepatic histology, lipoperoxidation and antioxidant activity of lung tissue, alveolar-arterial O2 difference and lung / body weight ratio (%) were evaluated. Results: When comparing the groups, could be observed an increase of vasodilation and pulmonary fibrosis in the BDL group and the reduction of this in relation to the BDL + MEL group. It was also observed significant changes in the activity of catalase, ApCO2, ApO2 in the LBD group when compared to the other groups. Conclusion: The use of MEL has been shown to be effective in reducing vasodilation, fibrosis levels and oxidative stress as well as gas exchange in an experimental HPS model.
RESUMO Objetivo: Avaliar as alterações pulmonares de animais com Síndrome Hepatopulmonar (SHP), submetidos à ligadura de ducto biliar (LDB), bem como o efeito antioxidante da Melatonina (MEL). Métodos: Dezesseis ratos machos da espécie Wistar, divididos em quatro grupos: Sham, Grupo LDB, Grupo Sham + MEL e LDB + MEL. Foram avaliadas a histologia pulmonar e hepática, a lipoperoxidação e atividade antioxidante do tecido pulmonar, diferença álveolo-arterial de O2 e relação peso pulmonar/peso corporal (%). Resultados: Quando comparados os grupos, observamos um aumento da vasodilatação e fibrose pulmonar no grupo LDB e a redução deste em relação ao grupo LDB+MEL. Observamos ainda alterações significativas na atividade da catalase, PaCO2, PaO2 no grupo LBD quando comparado aos demais grupos. Conclusões: A utilização da MEL demonstrou-se eficaz na redução da vasodilatação, níveis de fibrose e estresse oxidativo assim como na troca gasosa em modelo experimental de SHP.
Assuntos
Animais , Masculino , Síndrome Hepatopulmonar/tratamento farmacológico , Pulmão/efeitos dos fármacos , Melatonina/farmacologia , Antioxidantes/farmacologia , Ductos Biliares/cirurgia , Gasometria , Peroxidação de Lipídeos/efeitos dos fármacos , Catalase/análise , Síndrome Hepatopulmonar/fisiopatologia , Síndrome Hepatopulmonar/patologia , Modelos Animais de Doenças , Pressão Arterial/efeitos dos fármacos , Glutationa Transferase/análise , Ligadura , Fígado/efeitos dos fármacos , Fígado/patologiaRESUMO
INTRODUCTION: Lupus nephritis (LN) is one of the most severe complications of systemic lupus erythematosus. As murine models of LN are valuable tools to better understand its pathophysiology and to search for new effective treatments, we investigated the effects of the bioflavonoid quercetin on pristane-induced LN mice through histomorphological analyses. METHODS: Immunofluorescence and biochemical assays were used to evaluate the expression of markers of inflammation (interleukin-6, IL-6; tumour necrosis factor-α, TNF-α), oxidative stress (catalase, CAT; superoxide dismutase 1, SOD1; thiobarbituric acid reactive substances, TBARS), apoptosis (Bax), and fibrosis (transforming growth factor-ß1, TGF-ß1). Glomerular and tubular ultrastructure was analysed, and tissue messenger RNA of podocin, podoplanin and α3ß1-integrin were quantified using the real-time polymerase chain reaction. RESULTS: Pristane-induced LN mice showed severe kidney injury, characterized by increased proteinuria, glomerular mesangial expansion and inflammation, high expression of the pro-fibrotic, apoptotic and prooxidant markers and reduction of antioxidants. In the kidney ultrastructure, foot process (FP) effacement, apoptotic mesangial cells and abnormal mitochondria with disrupted cristae were observed, along with suppressed tissue mRNA of podocin, podoplanin and α3ß1-integrin. Treatment with quercetin in the pristane-induced LN mice model was nephroprotective, decreasing proteinuria levels and significantly lowering tissue expression of IL-6, TNF-α, TGF-ß1, Bax and TBARS. Simultaneously, quercetin significantly increased CAT and SOD1 expressions in these mice. In addition, it was observed improvement of the kidney ultrastructure, and tissue mRNA of podocin, but not podoplanin and α3ß1-integrin, was restored to the levels found in the control mice. CONCLUSION: In conclusion, these findings provide experimental evidence of the renoprotective effects of quercetin in the pristane-induced LN mice model. We suggest that quercetin effectively ameliorates the kidney damage caused by pristane, a bioflavonoid to be further evaluated as a new therapeutic strategy in this disease.