RESUMO
Metabolic syndrome and oxidative stress are common complications of type 2 diabetes mellitus. The present study was designed to determine whether resveratrol, a widely used nutritional supplement, can improve insulin sensitivity, metabolic complication as well as hepatic oxidative stress in fructose-fed rats. Male Sprague Dawley rats (180-200 g) were divided into four groups with 8 animals each. Fructose-fed insulin resistant group (Dia) animals were fed 65% fructose (Research diet, USA) for a period of 8 weeks, whereas control group (Con) animals were fed 65% cornstarch (Research Diet, USA). Resveratrol, 10 mg/kg/day (Dia+Resv) or metformin 300 mg/kg/day (Dia+Met) were administered orally to the 65% fructose-fed rats for 8 weeks. At the end of the feeding schedule, Dia group had insulin resistance along with increased blood glucose, triglyceride, uric acid and nitric oxide (NO) levels. Significant (p<0.05) increase in hepatic TBARS and conjugated dienes, and significant (p<0.05) decrease in hepatic SOD and vitamin C was observed in Dia group compared to Con group. Administration of metformin or resveratrol significantly (p<0.05) normalized all the altered metabolic parameters. However, a marked insulin sensitizing action was only observed in the Dia+Resv group. Similarly, while metformin administration failed to normalize the increased TBARS levels and decreased SOD activity, resveratrol showed a more promising effect of all oxidative stress parameters measured in the present study. Attenuation of hepatic oxidative stress in fructose-fed rat liver after resveratrol administration was associated with significant (p<0.05) increase in nuclear level of NRF2 compared with other groups. The present study demonstrates that resveratrol is more effective than metformin in improving insulin sensitivity, and attenuating metabolic syndrome and hepatic oxidative stress in fructose-fed rats.
Assuntos
Frutose/administração & dosagem , Resistência à Insulina/fisiologia , Insulina/metabolismo , Síndrome Metabólica/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Ácido Ascórbico/metabolismo , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Teste de Tolerância a Glucose/métodos , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/metabolismo , Metformina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico/sangue , Ratos , Ratos Sprague-Dawley , Resveratrol , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/farmacologia , Triglicerídeos/sangue , Ácido Úrico/sangueRESUMO
Fellutamide B is reported to have cytotoxic and proteasome inhibitory activity. Interestingly, fellutamide B and its simplified analogues have also been observed for the neurotrophic activity by stimulating the synthesis and secretion of neurotrophins. Owing to the interesting structural and potent neurotrophic role of fellutamide B (a lipopeptide aldehyde), we have assessed the synthetic path intermediates (compounds A-D) of fellutamide B for their neuroactive potential (in vitro and in vivo). We have observed few compounds (comp #A-D) to have potential neurite outgrowth activity in Neuro2a cells with no observable negative effect on the cell viability. In addition, most compounds (comp #A, C, and D) have shown neurogenic activity ex vivo in hippocampal neurosphere culture, with increased acetyl H3 and acetyl H4 induction ability (comp #C). Furthermore, the intermediate product comp #C has shown anxiolytic and antidepressant-like activity in novel tank test and social interaction test, in the chronic unpredictable stress model of zebrafish mood disorder, inducing BDNF gene expression in the telencephalon region of the fish brain. Our results thus demonstrate that the fellutamide B synthetic path intermediates have potential neurotrophic, neurogenic, and mood-elevating effects and thus good prospect to be developed as potential therapeutics to treat psychiatric disorders.
RESUMO
Hyperglycaemia in diabetes is either caused by reduced availability of insulin (type 1 diabetes, T1D) or insulin resistance to the cells (type 2 diabetes, T2D). In recent years, the prevalence of T2D has increased to an alarming proportion, encompassing 95 percent of the total diabetic burden, probably due to economy-driven changes in lifestyle. Recent epidemiological studies show comorbid depression, anxiety and related mental illness. To explore the molecular mechanisms underlying this comorbid conditions, we used Sprague-Dawley rats on high-fructose diet for 8 weeks to induce prediabetic condition. Rats with this metabolic syndrome also showed hyper-anxiety when they were subjected to anxiety-related behavioural assays. Rats were administered with resveratrol, an activator of sirtuins, and metformin, a standard antidiabetic drug, simultaneously with fructose. We observed that resveratrol was more effective in protecting from both the metabolic (prediabetic) and affective (anxiety) disorders than metformin. Molecular studies showed that recovery was associated with the upregulation of few nuclear sirtuins that act epigenetically - Sirt 1 and 7, which were significantly attenuated in the striatum of prediabetic rats. In conclusion, our study showed that hyper-anxiety associated with prediabetic condition is ameliorated by resveratrol through modulation of sirtuins, which is more or less similar to metformin.