Application of ultrasound in the dissolution of potential antiophidian compounds from two ethanolics extracts of two species of Heliconias

Heliconia rostrata rhizomes mitigate chemical-induced liver injury by debilitating oxidative stress in HepG2 cells and rats

ETHNOPHARMACOLOGICAL RELEVANCE

Heliconia rostrata Ruiz and Pav. belongs to the family Heliconiaceae. Plant was traditionally used to cure jaundice, intestinal pain, diabetes and hypertension.

AIM OF THE EXPERIMENT

Present study evaluated hepatoprotective efficacy of ethanol (REE) and methanol (RME) extracts of H. rostrata rhizomes in HepG2 cell lines and rats. Antioxidant efficacy of extracts was determined using ex vivo and in vivo methods.

MATERIALS AND METHODS

Before conducting efficacy studies, safety of REE and RME was established using toxicity studies which included Oral acute-fixed dose toxicity using OECD TG420, 28-days repeated dose oral toxicity by OECD TG407 and cytotoxicity studies by brine shrimp lethality (BSL) bioassay and MTT assay taking HepG2 cell line. Ex vivo (Extracts: 0-250 μg/ml) and in vivo (Extracts: 50, 100 and 200 mg/kg) antioxidant studies were performed on fresh goat liver and rats (N = 45) of either sex, respectively. In vitro hepatoprotective efficacy of extracts was evaluated against ethanol induced toxicity in HepG2 cell line. In vivo study was performed at 50, 100 and 200 mg/kg/day doses in rats by CCl₄-induced hepatotoxicity study.

RESULTS

No mortality was observed during single and repeated dose toxicity studies. 50% lethal dose >2000 mg/kg, confirmed category 5 toxicity level of extracts, according to Globally Harmonized System. No signs of toxicity and treatment or dose related changes recorded in rats under repeated dose toxicity study. No-observed-adverse effect-level of 200 mg/kg/day was observed for both extracts. Median lethal concentration of REE and RME were 1291.30 and 1045.89 μg/ml, respectively in BSL bioassay and 50% cytotoxicity concentration >1000 μg/ml was obtained for both extracts from MTT assay. Calculated 50% inhibitory concentration and median effective dose of extracts obtained from different antioxidant assays in ex vivo and in vivo antioxidant studies, respectively indicated REE has more antioxidant efficacy than RME. In in vitro hepatoprotective efficacy study, extracts demonstrated dose dependent protection against ethanol induced hepatotoxicity. At 400 μg/ml, REE and RME demonstrated percentage protection of 65.53% and 57.98%, respectively. Results of liver function test and histopathological evaluation of liver in in vivo hepatoprotective study confirmed dose dependent protection provided by the extracts against CCl₄ -induced hepatotoxicity.

CONCLUSION

Both REE and RME were found safe to be considered for therapeutic uses. Both REE and RME were found to exhibit antioxidant efficacy in ex vivo and in vivo models. Results ascertained that H. rostrata rhizomes possess significant hepatoprotective potency.

Plants and Phytocompounds Active Against Bothrops Venoms

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Snakebite envenomation is an important health problem in tropical countries, with severe human and social consequences. In Latin America, the Bothrops species constitute the main threat to humans, and the envenomation caused by these species quickly develops into severe local tissue damage, including swelling, hemorrhaging, myonecrosis, skin ulceration, and pain. The systemic effects of envenomation are usually neutralized by antivenom serum therapy, despite its intrinsic risks. However, neutralization of local tissue damage remains a challenge. To improve actual therapy, two major alternatives are proposed: the rational design of new specific antibodies for most of the tissue damaging/ poor immunogenic toxins, or the search for new synthetic or natural compounds which are able to inhibit these toxins and complement the serum therapy. Natural compounds isolated from plants, mainly from those used in folk medicine to treat snakebite, are a good choice for finding new lead compounds to improve snakebite treatment and minimize its consequences for the victims. In this article, we reviewed the most promising plants and phytocompounds active against bothropic venoms.

Evaluation of antimicrobial and cytotoxic activities of plant extracts from southern Minas Gerais cerrado

The antimicrobial activity of plant hidroethanolic extracts on bacteria Gram positive, Gram negative, yeasts, Mycobacterium tuberculosis H37 and Mycobacterium bovis was evaluated by using the technique of Agar diffusion and microdilution in broth. Among the extracts evaluated by Agar diffusion, the extract of Bidens pilosa leaf presented the most expressive average of haloes of growth inhibition to the microorganisms, followed by the extract of B. pilosa flower, of Eugenia pyriformis' leaf and seed, of Plinia cauliflora leaf which statistically presented the same average of haloes inhibitory formation on bacteria Gram positive, Gram negative and yeasts. The extracts of Heliconia rostrata did not present activity. Mycobacterium tuberculosis H37 and Mycobacterium bovis (BCG) appeared resistant to all the extracts. The susceptibility profile of Candida albicans and Saccharomyces cerevisiae fungi were compared to one another and to the Gram positive Bacillus subtilis, Enterococcus faecalis and the Gram negative Salmonella typhimurium bacteria (p > 0.05). The evaluation of cytotoxicity was carried out on C6-36 larvae cells of the Aedes albopictus mosquito. The extracts of stem and flower of Heliconia rostrata, leaf and stem of Plinia cauliflora, seed of Anonna crassiflora and stem, flower and root of B. pilosa did not present toxicity in the analyzed concentrations. The highest rates of selectivity appeared in the extracts of stem of A. crassiflora and flower of B. pilosa to Staphylococcus aureus, presenting potential for future studies about a new drug development.