Evaluation of the effect of alpha-tocopherol on anxiety and the neuroinflammatory process during alcohol withdrawal in a model of forced and chronic self-administration of liquid diet containing ethanol: Behavioral and neurochemical evidence.

Alcoholism affects about 2 billion people worldwide. Withdrawal causes a neuroinflammatory response that increases anxiety. α-tocopherol is the most important antioxidant that has its in vivo action currently known. Therefore, this study aimed to evaluate the effect of α-tocopherol on the neuroinflammatory process in brain regions involved in anxiety and its anxiolytic potential during alcohol withdrawal. For this, male Wistar rats were divided into four groups and submitted to a procedure of forced and chronic self-administration of liquid diet containing 6% and 8% ethanol for 15 days, followed by abrupt interruption of treatment. Animals in the control group received the liquid diet without ethanol. Twenty-four or 48 h after ethanol discontinuation, and 30 min after the last administration of α-tocopherol or saline, animals were evaluated in the elevated plus maze, light/dark box, and open field tests. At the end of the tests, each experimental group underwent brain tissue collection for analysis of cytokine levels. The results showed that: alcohol induces the neuroinflammatory process and anxiety; the stress generated by withdrawal can induce oxidative stress, which alters the production of inflammatory cytokines in the amygdaloid nuclei (AN) and medial hypothalamic nucleus (mHN); α-tocopherol exhibited anxiolytic and anti-inflammatory activity, attenuating the anxious behavior of abstinent animals and reducing neuroinflammation in AN and mHN; and the intensity of the anxiolytic and anti-inflammatory effect of α-tocopherol is dose-dependent. These results identify α-tocopherol as a potential therapeutic target supporting the fight against relapse during alcohol withdrawal.

Aqueous extract from Mangifera indica Linn. (Anacardiaceae) leaves exerts long-term hypoglycemic effect, increases insulin sensitivity and plasma insulin levels on diabetic Wistar rats.

BACKGROUND: Diabetes mellitus is one of the most common todays public health problems. According to a survey by the World Health Organization, this metabolic disorder has reached global epidemic proportions, with a worldwide prevalence of 8.5% in the adult population. OBJECTIVES: The present study aimed to investigate the hypoglycemic effect of aqueous extract of Mangifera indica (EAMI) leaves in streptozotocin-induced diabetic rats. METHODS: Sixty male rats were divided into 2 groups: Normoglycemic and Diabetic. Each group was subdivided into negative control, glibenclamide 3 or 10 mg/kg, EAMI 125, 250, 500, and 1000 mg/kg. Intraperitoneal injection of streptozotocin 100 mg/kg was used to DM induction. The hypoglycemic response was assessed acutely after two and four weeks of treatment. After a 6-hour fasting period, the fasting blood glucose of animals was verified, and 2.5 g/kg glucose solution was orally administered. The insulin tolerance test and plasma insulin levels assessment were performed in the morning after fasting of 12 to 14 hours. RESULTS AND CONCLUSION: The chemical analysis of EAMI showed high levels of phenolic compounds. There was no significant difference in fasting blood glucose between normoglycemic and diabetic groups, and that EAMI did not have an acute effect on diabetes. After two and four weeks of treatment, the extract significantly reduced blood glucose levels, exceeding glibenclamide effects. EAMI was effective in maintaining the long-term hypoglycemic effect, as well as, significantly increased the sensitivity of diabetic animals to insulin and the plasma insulin level.

The ethanolic extract obtained from Campomanesia pubescens (D.C.) O.BERG fruits exerts anxiolytic and antidepressant effects on chronic mild stress model and on anxiety models in Wistar rats: Behavioral evidences.

Objectives: Campomanesia pubescens (DC) O.BERG (Myrtaceae) fruits contain high levels of flavonoids and are widely consumed by the South American population. In the central nervous system (CNS), some flavonoids act as modulators of GABA-A receptors and monoamine oxidase inhibitors, resulting in anxiolytic antidepressants effects, respectively. The objective of the present study was to evaluate the anxiolytic and antidepressant effects of ethanolic extract of C. pubescens fruits (EEFCP) in rats.Methods: In order to prove the antidepressant effect of the EEFCP, rats were submitted to the chronic mild stress model, to the sucrose preference test (SPT), and the forced swimming test. To test the anxiolytic effects, the Elevated plus-maze (EPM), open field (OF), and Marble-Burying models were used.Results: After 2 weeks of treatment, imipramine 25 mg/kg, EEFCP 250 mg/kg, and EEFCP 500 mg/kg reversed the anhedonic behavior measured by SPT and significantly reduced the immobility time of animals under stress. In addition, treatment with diazepam 2 mg/kg, EEFCP 250 mg/kg, and EEFCP 500 mg/kg increased the percentage of entries and time spent on the open arms of the EPM, increased locomotion, rearing, and reduced the grooming time in OF.Discussion: The chemical analysis of the EEFCP indicated high content of flavonoids and the behavioral analysis revealed an antidepressant and anxiolytic effect, suggesting that these phytochemicals may be involved with these actions in the CNS.

Preclinical safety evaluation of the aqueous extract from Mangifera indica Linn. (Anacardiaceae): genotoxic, clastogenic and cytotoxic assessment in experimental models of genotoxicity in rats to predict potential human risks.

ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants widely used by the population contain significant concentrations of biologically active compounds and, although they have proven pharmacological properties, can cause DNA damage and develop fatal diseases. AIM OF THE STUDY: The present study aimed to evaluate the genotoxic, cytotoxic potential and clastogenic effects of the aqueous extract from Mangifera indica leaves (EAMI) on rats submitted to experimental genotoxicity models and through the SMART test performed in Drosophila melanogaster. MATERIAL AND METHODS: The comet assay and the micronucleus test were performed on peripheral and bone marrow blood, respectively, of Wistar rats, orally treated with EAMI at doses of 125, 250, 500 and 1000 mg/kg/bw for 28 days. In the SMART test, the standard cross between three mutant D. melanogaster strains was used. Larvae were treated with EAMI at different concentrations, and the wings of adult flies were evaluated for the presence/frequency of mutant spots and compared to the negative control group. RESULTS: Phytochemical analysis of EAMI indicated high levels of flavonoids. The tests performed in rats showed that EAMI did not present significant genotoxic or clastogenic effects. The results showed a critical dose-dependent cytoprotective effect exerted by EAMI. This result was attributed to the high content of polyphenols and flavonoids. The biotransformation metabolites of EAMI did not present genotoxic activity, as demonstrated by the SMART test. CONCLUSIONS: These results are relevant since they provide safety information about a plant species of great therapeutic, economical, nutritious and ethnopharmacological value for the population.

Preclinical safety evaluation of the ethanolic extract from Campomanesia pubescens (Mart. ex DC.) O.BERG (guavira) fruits: analysis of genotoxicity and clastogenic effects.

Genotoxicity studies of plants with medicinal and nutritional properties are recommended by international regulatory agencies as part of the risk assessment. Due to their consumption as food, nutraceutical use and ethnopharmacological relevance, Campomanesia pubescens represents one of these plants to be studied. The aim of the present study was to evaluate the genotoxic, cytotoxic potential and clathogenic effects of the ethanolic extract obtained from the pulp of C. pubescens (EEFCP) fruits on rats submitted to experimental genotoxicity models and through the SMART test performed in Drosophila melanogaster. The comet assay and the micronucleus test were performed on peripheral and bone marrow blood, respectively, of Wistar rats orally treated with EEFCP at doses of 125, 250, 500 and 1000 mg per kg per bw for 28 days. In the SMART test, the standard cross between three mutant D. melanogaster strains was used. Larvae were treated with EEFCP at different concentrations and the wings of adult flies were evaluated for the presence/frequency of mutant spots and compared to the negative control group. Phytochemical analysis of EEFCP indicated high levels of flavonoids. The tests performed in rats showed that EEFCP did not present significant genotoxic or clastogenic effects. The biotransformation metabolites of EEFCP did not present genotoxic activity, as demonstrated by the SMART test. Together, all results indicate that, under the experimental conditions used, EEFCP did not reveal any preclinical genetic toxicity. Therefore, the safe consumption can be fomented increasing, consequently, the economic liquidity in the industrial market from the fruits of guavira.

Preclinical safety evaluation of the ethanolic extract from guavira fruits (Campomanesia pubescens (D.C.) O. BERG) in experimental models of acute and short-term toxicity in rats.

Campomanesia pubescens is a fruit plant widely distributed in South America and used by the population for medicinal and nutritional purposes, with important economic and cultural value. This study evaluated the toxic potential of the ethanolic extract from C. pubescens (EEFCP) fruits through acute and short-term toxicity tests. For the acute toxicity test, female rats received a single oral dose of 2000 mg/kg body weight of EEFCP and were observed for 14 days. In the short-term toxicity test, male and female rats received repeated oral doses of 125, 250, 500 or 1000 mg/kg of EEFCP, being treated and observed for 28 days, and after the treatment period, a satellite and satellite control group remained under observation for another 14 days. No mortality, clinical and organ weight alterations were observed, indicating that LD50 is greater than 2000 mg/kg body weight. In addition, the doses tested did not produce significant changes in the behavioral, physiological, hematological or histopathological parameters of animals. These results demonstrate the low acute and short-term toxicity of EEFCP in rats. The data obtained are of great relevance since they provide important information about a plant species of great economic, nutritional and ethnopharmacological value.