Clastogenicity of the Austroplenckia populnea (Celastraceae) Bark Wood Extract in Wistar Rat Bone Marrow Cells

Mutagenic, antioxidant and wound healing properties of Aloe vera

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe vera is a widely used medicinal plant for its various biological activities. This study evaluate possible mutagenic and healing effects of the aqueous extract of A. vera (AEAV) in mice and its oxidant/antioxidant potential in different proficient and deficient Saccharomyces cerevisiae strains.

MATERIAL AND METHODS

The AEAV was topically treated on the wounded skin surface of male albino mice at doses of 10 and 50 mg/kg for seven successive days. The control group was similarly treated with 0.9% NaCl solution. For oxidative/anti-oxidative evaluation, both proficient and deficient strains of S. cerevisiae [cytoplasmic and mitochondrial superoxide dismutase mutant (SOD: Sod1Δ and Sod2Δ), cytoplasmic catalase mutant (CAT: Cat1Δ)], two double defective mutants of Sod1 and Sod2 and Sod1 and Cat1 genes along with a wild-type strains were used.

RESULTS

The healing property of AEAV was observed at the dose of 50 mg/kg but at the same dose it showed mutagenic and cytotoxic effects in peripheral blood. AEAV did not produce the oxidizing effect, except in the mutated CAT strain at highest concentration (50 mg/kg).

CONCLUSION

The high concentration of AEAV showed mutagenicity and cytotoxicity. Beside, the healing capacity is believed to be due to its anti-oxidative defense mechanism.

Cytogenotoxicity of Cymbopogon citratus (DC) Stapf (lemon grass) aqueous extracts in vegetal test systems

The lemon grass, Cymbopogon citratus (DC) Stapf, is an important species of Poaceae family commonly used in the folk medicine in many countries. The aim of this study was to investigate the cytotoxic and genotoxic effects of aqueous extracts from C. citratus leaves on Lactuca sativa (lettuce) root tip meristem cells by cytogenetic studies that have never been done before for lemon grass extracts. For this, lettuce seeds were treated for 72h with different concentrations of lemon grass aqueous extracts (5; 10; 20 and 30 mg/mL). The percentage of germination, root development and cellular behavior were analyzed, and the results showed that the highest concentration of aqueous extracts reduced the mitotic index, the seed germination and the root development of lettuce. The extracts have also induced chromosome aberrations and cellular death in the roots cells of L. sativa.

Evaluation of the genotoxic potential of Austroplenckia populnea (Reiss) Lundell chloroform fraction from barkwood extract in rodent cells in vivo

The genotoxic effect of the Austroplenckia populnea chloroform fraction from barkwood extract was tested in vivo on peripheral blood cells of Swiss mice with the comet assay (SCGE), and the clastogenic effect was investigated on peripheral blood cells of Swiss mice and bone marrow cells of Wistar rats, with the micronucleus and chromosome aberrations tests. The animals were treated by gavage with 3 concentrations of the extract: 300, 600 and 900 mg.kg-1. Peripheral blood cells of Swiss mice were collected 4 and 24 hours after the treatment to the SCGE assay and 48 and 72 hours to the micronucleus test. Bone marrow cells of Wistar rats were collected 24 hours after the treatment to the micronucleus and chromosome aberration tests. The results showed that the A. populnea chloroform fraction induced an increase in the average number of DNA damage in peripheral blood cells at the three concentrations tested, but this increase was not statistically significant. In the micronucleus and chromosome aberrations test, no significant increase was observed in the mean number of micronucleated polychromatic erythrocytes (MNPCE) of Swiss mice or MNPCE or chromosome aberrations for the rat bone marrow cells, for any of the tested doses. Our findings enable us to conclude that by the comet assay, A. populnea chloroform fraction from barkwood extract showed no genotoxic effects, and by the micronucleus and chromosome aberration tests, the extract fraction showed no clastogenic/aneugenic effects on the rodent cells tested.