Non-clinical acute and chronic toxicity evaluations of Cissus sicyoides L. (Vitaceae) hydroalcoholic leaf extract.

Cissus sicyoides (Cs) has been traditionally used to treat diabetes and belongs to the family Vitaceae, and is known as "vegetable insulin". This study aimed to evaluate the acute and chronic non-clinical toxicity of hydroalcoholic extract from the leaves of Cissus sicyoides (EHA-Cs). The acute test was performed in Wistar rats, administering a single dose of 40.5 mg/kg. Behavioral parameters for pharmacological screening were observed to detect signs of Central Nervous System activity; consumption of daily food and water, and weight evaluation. After day 14, the animals were euthanized and blood samples were collected for laboratory analyses of hematological and biochemical parameters. The chronic tests were administered in doses of 4.5, 13.5 and 40.5 mg/kg. The same parameters were observed together with body temperature, glucose, exploration activity (test on the open field), and motor activity (diagnostic tests on the Rota-rod). For the group given the highest dosage during the study, histopathological examinations of vital organs were performed. For acute toxicity, there were no CNS level effects, changes in water and food consumption, or hematologic parameters. However, there was a significant decrease in weight gain for the treated females. Biochemical analyses of the treated animals presented increased levels of AST (aspartate aminotransferase) in females, uric acid levels in females and males, and amylase in males. In the chronic toxicity tests, water consumption was higher for females (at the dosages of 13.5 and 40.5 mg/kg) and for males (at 40.5 mg/kg). At the dosages of 4.5 and 13.5 mg/kg, feed consumption increased for females, while for males it decreased along with weight gain. Blood analysis presented an increase in albumin and changes in erythrocytes and hemoglobin for males (at the dose of 13.5 mg/kg). Glycemia in females (13.5 mg/kg dose) was significantly less, presenting only slight drops at the other doses. The changes were reversible in the satellite group. EHA-Cs revealed a relatively low toxicity profile (at the popular use dose), and only small changes in hematological and biochemical parameters at the dose of 13.5 mg/kg (3x the popular use dosage). In addition, EHA-Cs did not promote histological changes in vital organs such as the heart, lungs, liver and kidneys.

Anticonvulsive activity of (1S)-(-)-verbenone involving RNA expression of BDNF, COX-2, and c-fos.

(1S)-(-)-verbenone (VRB) is a monoterpene present in the essential oils of many plants which has shown therapeutic effect; however, its anticonvulsant activity has not yet been evaluated. The present work sought to investigate the anticonvulsant activity of VRB using pilocarpine and pentylenetetrazole-induced seizure testing; seeking also probable mechanisms of action. VRB caused no significant changes in motor coordination. Also, no significant data was observed in the pilocarpine-induced seizure tests. In the PTZ-induced seizures test, VRB showed anticonvulsant activity at doses of 200 mg/kg i.p. (733 ± 109.4 s) and 250 mg/kg i.p. (648.8 ± 124.5 s) significantly increasing the latency to onset of first seizure as compared with the vehicle group (51.8 ± 2.84 s). Pretreatment with flumazenil (FLU) did not reverse the anticonvulsive effect of VRB; however, it was able to upregulate BDNF and COX-2 genes and downregulate c-fos. The findings suggest that the anticonvulsant effects of VRB may be related to RNA expression modulations of COX-2, BDNF, and c-fos.

Ocimum basilicum: Antibacterial activity and association study with antibiotics against bacteria of clinical importance.

CONTEXT: Ocimum basilicum L. (Lamiaceae), popularly known as basil, is part of a group of medicinal plants widely used in cooking and known for its beneficial health properties, possessing significant antioxidant effects, antinociceptive, and others. OBJECTIVE: The objective of this study is to determine the pharmacological effects produced on the bacterial strains Staphylococcus aureus and Pseudomonas aeruginosa when standard antibiotics and O. basilicum essential oil are combined. MATERIALS AND METHODS: The extraction of O. basilicum (leaves) components was done by steam distillation. The Minimum inhibitory concentration (MIC) was calculated using microdilution technique, where the oil concentrations varied from 2 to 1024 µg/mL. The combinations of O. basilicum oil with ciprofloxacin or imipenem were analyzed by the checkerboard method where fractional inhibitory concentration (FIC) indices were calculated. RESULTS: Ocimum basilicum essential oil, imipenem, and ciprofloxacin showed respective MIC antibacterial activities of 1024, 4, and 2 µg/mL, against S. aureus. In S. aureus, the oil with imipenem association showed synergistic effect (FIC = 0.0625), while the oil with ciprofloxacin showed antagonism (FIC value = 4.25). In P. aeruginosa, the imipenem/oil association showed additive effect for ATCC strains, and synergism for the clinical strain (FIC values = 0.75 and 0.0625). The association of O. basilicum essential oil with ciprofloxacin showed synergism for clinical strains (FIC value = 0.09). CONCLUSION: Ocimum basilicum essential oil associated with existing standard antibiotics may increase their antibacterial activity, resulting in a synergistic activity against bacterial strains of clinical importance. The antibacterial activity of O. basilicum essential oil may be associated with linalool.

Purification and biological activities of Abelmoschus esculentus seed lectin.

The Abelmoschus esculentus (Malvaceae) plant originated in Africa and has spread across a number of tropic countries, including northeastern Brazil. The plant has been used to treat various disorders, such as cancer, microbial infections, hypoglycemia, constipation, urine retention and inflammation. The lectin of A. esculentus (AEL) was isolated by precipitation with ammonium sulfate at a saturation level of 30/60 and purified by ion exchange chromatography (Sephacel-DEAE). The electrophoresis (SDS-PAGE) profile of the AEL showed two protein bands of apparent molecular mass of approximately 15.0 and 21.0 kDa. The homogenity of the protein was confirmed by electrospray mass spectrometry (ESI-MS), which revealed the presence of a 10.29-kDa monomer and a 20.58-kDa dimer. The AEL exhibits agglutinating activity against rabbit (74.41 UH/mP) and human type ABO erythrocytes (21.00 UH/mP). This activity does not require the presence of divalent cations and is specifically inhibited by lactose, fructose and mannose. The intravenous treatment with 0.01, 0.1 and 1 mg/kg of AEL inhibited the paw edema elicited by carrageenan by approximately 15, 22 and 44 %, respectively, but not that induced by dextran. In addition, treatment with 0.1, 1 and 10 mg/kg of AEL also inhibited the abdominal writhing induced by acetic acid by approximately 52, 57 and 69 %, respectively. In conclusion, AEL is a new lectin with a molecular mass of 20.0 kDa, which is -composed of a 10.291-Da monomer and a 20.582-kDa dimer, that exhibits anti-inflammatory, antinociceptive and hemagglutinating activities. In addition, the lectin hemagglutinating property is both metallo-independent and associated with the lectin domain.