MATERIALS AND METHODS: The study group comprised of 30 healthy subjects, 15 males and 15 females, aged between 24 years and 65 years. Samples were obtained from the exfoliated oral mucosa cells of buccal mucosa before and 12 days after exposing the patients to panoramic radiography.
RESULTS: The study reported that there was no significant increase in the number of micronuclei cells present before and after panoramic radiography. Positive correlation existed between age with pre- and postexposure micronuclei.
CONCLUSION: Diagnostic dental panoramic radiograph does not induce micronuclei in the target buccal epithelium cells. A positive correlation between age and micronuclei frequency was established.
CLINICAL SIGNIFICANCE: Panoramic radiographs does not induce cytotoxicity but increase frequency may be vulnerable to genotoxic effects in buccal mucosal cells. Hence, dental radiographs should be prescribed only when necessary.
AIM OF THE STUDY: To assess the in vitro mutagenicity and in vivo genotoxicity of aqueous extract of V. officinalis leaves using a modified Ames test and rat bone marrow micronucleus assay according to OECD guidelines.
MATERIALS AND METHODS: In vitro Ames test was carried out using different strains of Salmonella (TA97a, TA98, TA100, and TA1535) and Escherichia coli WP2 uvrA (pKM101) in the presence or absence of metabolic activation (S9 mixture). For micronucleus experiment, male and female Sprague-Dawley rats (n = 6/group) were received a single oral daily dose of 500, 1000, and 2000 mg/kg of V. officinalis extract for three days. Negative and positive control rats were received distilled water or a single intraperitoneal injection of 50 mg/kg of cyclophosphamide, respectively. Following dissection, femurs were collected and bone marrow cells were stained with May-Grünwald-Giemsa solution for micronucleus assessment.
RESULTS: Ames test results demonstrated that 5, 2.5, 1.25 and 0.625 mg/ml of V. officinalis extract induced a significant mutagenic effect against TA100 and TA98 strains (with and without metabolic activation). Findings of the animal study showed there were no significant increase in the micronucleated polychromatic erythrocytes (MNPE) and no significant alterations in the polychromatic erythrocytes (PCE) to normochromatic erythrocytes (NCE) ratio of treated rats as compared with their negative control. Meanwhile, significantly increased in the MNPEs was seen in the cyclophosphamide-treated group only.
CONCLUSION: Aqueous extract of V. officinalis has mutagenic effect against TA98 and TA100 strains as demonstrated by Ames test, however, there is no in vivo clastogenic and myelotoxic effect on bone marrow micronucleus of rats indicating that the benefits of using V. officinalis in traditional practice should outweigh risks.
MATERIALS AND METHODS: Silymarin was isolated from seeds of milk thistle. Various genotoxicity bioassays of silymarin were performed using mice. First, the bone marrow cell proliferation was estimated by calculating mitotic index. Second, the chromosomal abnormalities in mice bone marrow cells were studied. Third, micronucleated polychromatic erythrocytes (MPE) test and in vivo activation of sister chromatid exchanges (SCEs) were carried out in mice bone marrow cells. Finally, primary spermatocytes were analyzed to estimate genotoxic effect of silymarin on germ cells.
RESULTS: We found that silymarin is capable of inducing a significant increase (P ≤ 0.05) in cell proliferation of bone marrow cells. There is no increase in chromosomal aberrations following silymarin treatments. Results clearly showed that it significantly (P ≤ 0.05) decreased the MPE. Likewise, it was found to be a negative inducer of SCEs. It decreased in total abnormal metaphase, SCEs, MPE, and aberrant diakinesis.
CONCLUSION: The results demonstrated that silymarin has a strong anticlastogenic activity upon mice genome in somatic and germ cells, indicating its safe use as a medicinal substance. Furthermore, it is not only safe but also has protective effect from clastogens.