1. EVALUATION OF THE POTENTIAL IN VIVO GENOTOXICITY OF QUERCETIN
OLIVEIRA, G. K1.; FRIAS, U. A1.; ALVES, M. C1.; MARCELINO, D. P. 1; MESSORA, M. R2; MENDES-COSTA, M.C1.
1Centro Universitário de Lavras- UNILAVRAS
2 Universidade de São Paulo – USPRP
RESULTS AND DISCUSSION
INTRODUCTION
The use of medicinal plants has become a therapeutic alternative resource of wide acceptance by the population and is growing along with the medical community. However great part of the native Brazilian plants still do not have scientific studies to enable the safe and effective use of the same. The lack of detailed information about the active principles of Banisteriopsis anisandra A. Juss, in particular the flavonoid Quercetin-3-O-Ramnosideo, makes it attractive for studies. This study aimed at removing rich flavonoids fractions from leaves of B. anisandra and prospect for genotoxic effects of the flavonoid quercetin-3-O-ramnosideo in polychromatic erythrocytes bone marrow of rats in vivo.
Figure 1 shows the micronuclei induced in the bone marrow cells after exposure of rats to the test sample. Compared with the negative control, there was a statistically significant(p<0.001),dose-dependent increase in MN at all concentrations. Generally, micronuclei are forms resulting from the aggregation of whole chromosomal or chromosome/chromatid fragments, aberrations and disturbances in the mitotic process. Our study provides additional and original in vivo information on the genotoxicity of the flavonoid Quercetin-3-O-Ramnosideo extracted from leaves of B. anisandra. Our findings are of great importance to public health seeing that medicinal plants has been implicated in everyday use by people in developing nations as Brazil.
MATERIAL AND METHODS
Flow chart of the procedure for preparation of Quercetin
The substance was administered via needle gavage once daily in 8 young Wistar rats (250kg each) during two consecutive days. The animals were sacrificed after 48 h of the last administration. The dosages used were 2.5 , 5 and 7.5(mg) of the test sample as against negative (distilled water) and positive (cyclophosphamide 50mg/kg body weight) controls. After the sacrifice of the animal the femurs were removed from each and bone marrow flushed from the bones with Foetal Bovine Serum. Cells were centrifuged at 2000rpm for 5min and slides stained with Leishman eosin-blue 24h after the preparation of the slides. Two smears were submitted for each animal. At least 1000cells/animal were scored for micronuclei in polychromatic erythrocytes(MNPCE). The differential staining of PCEs (bluish-purple) and normochromatic erythrocytes (NCEs,pinkish-orange),and the relative size of the erythrocytes, were indices for differentiating them. The statistical analyzes used were Tukey test and regression analysis. This study was approved by the Animal Research Ethics Committee of the Centro Universitário de Lavras.
Figure 2 shows micronuclei in erythrocytes of bone marrow rats after administration of Quercetin-3-O-Ramnosideo.
CONCLUSION
MN analysis showed a dose-dependent induction of micronucleated polychromatic erythrocytes across the treatment groups. These observations were provoked by the toxic and genotoxic effects of Quercetin-3-O-Ramnosideo present in the leaves of Banisteriopsis anisandra. .
REFERENCES
FREITAS.L.B.O. Estudo fitoquímico e da atividade biológica de Banisteriopsisanisandra (A. Juss) B. Gates e síntese de amidas indólicas para avaliação da atividade alelopática f. Dissertação (Mestrado em Química- Química Orgânica)- UFMG Instituto de Ciências Exatas Departamento de Química, Belo Horizonte, 2010.