Abstract
A Mandevilla velutina crude extract was investigated using the mouse micronucleus test (MNT) and the Drosophila melanogaster somatic mutation and recombination test (SMART) using standard (ST) and high bioactivation (HB) crosses. The MNT used 10 mg, 20 mg or 40 mg per 100 g of body weight (bw) of extract with and without 0.2 mg per 100 g bw peritoneal cyclophosphamide. There was no genotoxicity in the negative control or extract only groups and, compared to the cyclophosphamide control, there was a significant reduction in micronucleated polychromatic erythrocytes in all the groups given extract plus cyclophosphamide. For SMART larvae were fed 5 or 10 mg mL-1 of extract for seven days with and without 0.89 mg mL-1 of urethane given on day seven. The ST and HB flies showed no significant differences in spots between the negative control and the extract only groups. The number of urethane-induced spots was reduced by the highest concentration of extract for the ST flies and by both concentrations of extract for the HB flies. The results suggest that M. velutina extract is not genotoxic but is antigenotoxic.
Highlights
The frequency of micronucleated PCE (MNPCE) ± the standard deviation (SD), for male Swiss albino mice in the distilled water negative control group was 4 + 0.71, while for three groups of mice treated with the equivalent of 10 mg, 20 mg or 40 mg per 100 g bw of extract the frequency of MNPCE was 5.4 + 2.68 for the 10 mg group, 0.7 + 1.14 for the 20 mg group and 2.3 + 2.51 for the 40 mg group
For the experimental groups pre-treated with the equivalent of 10 mg, 20 mg or 40 mg per 100 g bw of extract and given cyclophosphamide we found that all the groups showed significantly lower frequencies of MNPCE as compared to the cyclophosphamide positive control group, the frequencies of MNPCE were 6.7 ± 5.32 for the 10 mg group, 2.6 ± 2.77 for the 20 mg group and 5.1 ± 1.64 for the 40 mg group (Table 1)
The pooled data recorded in the marker-heterozygous (MH) flies are shown in Table 2 and demonstrate that no statistically significant differences in spot frequencies were observed for either the standard (ST) or the high bioactivation (HB) cross after chronic treatment of larvae with 5 mg mL-1 or 10 mg mL-1 of extract, indicating that under these experimental conditions the extract showed no MNPCE per mouse
Summary
The pregnane glycoside compounds isolated from M. velutina have been shown to be effective in antagonizing bradykinin (BK) responses in a variety of preparations and exhibit potent and long-lasting analgesic, anti-inflammatory and anti-oedematogenic activities against a variety of inflammatory and fever-inducing phlogistic agents but was more effective in inhibiting processes involving kinins (Calixto and Yunes, 1991; Henriques et al, 1991; Maraschin et al, 2000). Detailed spectroscopic analysis has shown the structure of the potent bradykinin antagonist velutinoside A to be a pentasaccharide derivative of velutinol A, with the unusual sugars oleandrose and digitalose (Bento et al, 2003)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have