Micronuclei In Normochromatic Erythrocytes Research Articles

Radioprotective effect of Zamzam (alkaline) water: A cytogenetic study

BackgroundRadioprotectors are useful compounds to reduce radiation toxicity of normal cells. Many natural radioprotectors have antioxidant power and display fewer toxicity and side effects than the chemical ones. Alkaline waters such as Zamzam have antioxidant power potentially. This study aimed to investigate the radioprotective effect of Zamzam water in mice bone marrow exposed to gamma radiation by micronuclei test. MethodFive study groups including control group which was fed by ordinary water, the second group was fed by Zamzam water, and radiation groups were received 2Gy gamma with ordinary and Zamzam water for 10 days and another for 20 days. The frequency of micronuclei and polychromatic erythrocytes to normochromatic erythrocytes ratio were calculated by micronuclei test. ResultIn the absence of radiation, no significant difference was found between Zamzam group and control in the number of micronuclei in normochromatic erythrocytes, micronuclei in polychromatic erythrocytes, and the polychromatic erythrocyte to polychromatic erythrocyte plus normochromatic erythrocyte ratio. But all of these indices were significantly different between irradiated and non-irradiated groups. The frequency of micronuclei in polychromatic erythrocytes was not significantly different between 10 and 20 days Zamzam irradiated groups, but the reduction in micronuclei in normochromatic erythrocytes and an increase in the polychromatic erythrocyte to polychromatic erythrocyte plus normochromatic erythrocyte ratio compared to ordinary water were seen in 20 days Zamzam group. Dose reduction factor was 1.36 and 2 for Zamzam water groups of 10 days and 20 days, respectively. ConclusionThe results demonstrated that Zamzam alkaline water could reduce clastogenic and cytotoxic effects of gamma irradiation.

Genotoxicity of Different tert-Butylcalix[4]crowns

The ability of two calix[4]arene derivatives, namely 25,27-p-tert-butylcalix[4]dithiooxabenzocrown (1) and 25,27-p-tert-butylcalix[4]trithiooxabenzocrown (2), to produce chromosomal aberrations in root meristematic cells of Allium cepa and micronuclei (MN) in normochromatic erythrocytes (NCE) of Balb/c mice was investigated. NCE are normal mature red blood cells with a full complement of hemoglobin but lack ribosomes. In the first test, the root tips were treated with a series of concentrations of the two test chemicals ranging from 10(-7) to 10(-4) M for 24 or 48 h. Both compounds caused concentration-dependent increases in the percentage of aberrant cells and reductions in the mitotic index. These effects depended, to some extent, on the duration of the treatment. The most conspicuous chromosomal abnormalities were c-mitosis, chromosome bridges, chromosome breaks, chromosome lags as well as micronuclei and multinuclei. In the second test, acridine orange fluorescent staining was applied to evaluate the incidence of MN in NCE of mice intraperitoneally injected with varying contents of the two test chemicals (0.02-0.08 mg/mouse). The two chemicals induced dose-dependent MN formation as compared to the negative control. The second compound had more pronounced cytogenetic influence than the first one. Mitomycin C (MMC, 14 mg/kg body weight), employed as positive control, produced more obvious effects on the parameters investigated.

Induction of micronuclei by vinyl acetate in mouse bone marrow cells and cultured human lymphocytes

A dose-dependent increase in micronucleated polychromatic erythrocytes was observed in the bone marrow of male C57B1/6 mice 30 h after a single intraperitoneal injection of vinyl acetate (250, 500, 1000 or 2000 mg/kg b.wt.; (9–14 animals per group). The effect was statistically significant at 1000 mg/kg (1.33±0.29 vs. 0.6±0.0% in olive oil-treated controls) and at 2000 mg/kg (1.57±0.19%) of vinyl acetate. These doses were fatal to 6 (100 mg/kg) and 8 (2000 mg/kg) out of 14 animals in both groups. The ratio of polychromatic to normochromatic cells decreased as a function of vinyl acetate dose. Cyclophosphamide (20 mg/kg), used as a positive control chemical, induced a clear increase in micronucleated polychromatic erythrocytes (2.07±0.20%). None of the treatments affected the number of micronuclei in normochromatic erythrocytes. In human whole-blood lymphocyte cultures, micronucleus induction by a 48-h treatment with vinyl acetate (0.125, 0.25, 0.5, 1 and mM; 24 h after culture initiation) was studied in lymphocytes with preserved cytoplasm from smear prepared by a method involving the removal of erythrocytes at harvest by sodium cyanide treatment to improve preparation quality. The frequency of micronucleated lymptocytes reached a peak at 0.5 mM (3.2±1.0% vs. 0.9±0.1% in control cultures) and 1 mM (3.1±0.7%), with a decline at 2 mM probably because of a toxic effect resulting in mitotic inhibition.