José Ângelo Silveira Zuanazzi

Anxiolytic-, antidepressant- and anticonvulsant-like effects of the alkaloid montanine isolated from Hippeastrum vittatum

Compounds isolated from different members of the Amaryllidaceae family are becoming relevant options for the treatment of neurological disorders and neurodegenerative diseases. In particular, species of the Hippeastrum genus are important source of alkaloids with a wide profile of putative therapeutical applications. Here, we report on the behavioral and pharmaco-toxicological characterization of montanine, an isoquinoline alkaloid isolated from Hippeastrum vittatum, an ornamental plant found throughout the world. In mice, montanine showed a LD(50) of 64.7 mg/kg and 67.6 mg/kg for male and female, respectively. When given i.p., montanine dose-dependently decreased sodium pentobarbital-induced sleep, protected against pentylenetetrazole-provoked convulsions, increased the number of entries and the time spent in the open arms of an elevated plus maze and augmented the time spent struggling during a forced swimming test. When given immediately after inhibitory avoidance training, montanine did not affect avoidance memory retention in rats. Our results suggest that montanine, as other alkaloids isolated from Amaryllidaceae species, has psychopharmacological activities including anxiolytic, antidepressive and anticonvulsive effects.

Antioxidant potential of peels and fleshes of peaches from different cultivars.

Increasing recent interest in nutraceuticals and functional foods has led researchers to investigate the antioxidant potential of several fruits. This article evaluates the antioxidant potential and reactivity based on luminol-enhanced chemiluminescence capacity of peach extracts (peels and fleshes) and the contribution of a major compound present in these extracts to antioxidant potential and reactivity. The results obtained showed that the extracts of peels and fleshes of Maciel, Leonense, and Eldorado peach cultivars present free radical scavenging activity in all concentrations tested, with a concentration-dependent action. The immediate inhibition of chemiluminescence and the duration of this inhibition were significantly higher with the extracts than with the major compound (chlorogenic acid) alone, and it can be due to a synergistic or additive effect of other antioxidants present in the extracts. The 50% inhibitory concentration (IC(50)) values for peach extract and chlorogenic acid were 1.19 microg/mL and 8.43 microg/mL, respectively, when total radical-trapping antioxidant potential was evaluated, whereas IC(50) values of 0.41 microg/mL and 1.89 microg/mL was found when total antioxidant reactivity was evaluated in peach extract and chlorogenic acid, respectively. Chlorogenic acid presented a good contribution to antioxidant reactivity and potential, but the fruit extracts provide better antioxidant action. Peach could be of great interest as an important antioxidant source including chlorogenic acid, and it may provide health-promoting advantages to consumers by intake of this fruit or by utilization of its peels as antioxidant sources in industry.

Original Article. Toxicity of Glandularia selloi (Spreng.) Tronc. leave extract by MTT and neutral red assays: influence of the test medium procedure

Abstract Cytotoxicity assays using cell cultures may be an alternative to assess biological toxicity of plant extracts with potential phytotherapeutic properties. This study compared three methods to prepare culture media for the exposure of Vero cells to plant extracts. Leaves of Glandularia selloi (Spreng.) Tronc. were used to prepare culture medium with aqueous extract, extract in culture medium and methanol extract. Toxicity was assessed using the MTT and neutral red (NR) assays. In general, alterations in the cellular functions were found in all extracts and assays. Cytotoxic effect occurred at lower doses in aqueous extract and the range of effect of the methanol extract was small. The procedure of preparing the test medium has an effect on the outcome of the assay. Cytotoxicity of plant extract can be assessed by MTT and NR assays. Aqueous extract added to the culture medium presented the best profile to assess cytotoxicity.