Micronuclei and ageing in a sample of Yugoslavian population

OBJECTIVE: Instability in the organization and expression of the genetic material has been hypothesized as the basic mechanism of ageing. Aim of this study was to quantify the effect of ageing on spontaneous micronuclei (MN) frequency in peripheral blood lymphocytes. METHOD: Analysis of Yugoslavian population sample (164 tested individuals, age 0-62 years) has performed by application of cytokinesis-block technique (CB). RESULTS: There was an increase of MN frequency with age, from newborns to 40-year-old persons. The total average of MN frequency per 1000 analyzed binuclear cells amounts to 8.03 +/- 0.42, with variation from 0 to 26 MNs. In a sample of 29 newborns the recorded average MN frequency was 6.91 +/- 0.81, while among 69 persons 25-39 years old, the MN frequency was 9.16 +/- 1.00. The lowest average MN frequency, however, was noted in the sample of 34 tested individuals 40 to 62 years of age. CONCLUSION: An increase with age in MN frequency has been observed in samples of studied individuals from newborns to 40-year-old persons. A decrease of MN frequency in older groups could be explained by a gradual decrease of proliferative cell capacities.     

Micronuclei and Ageing in a Sample of Yugoslavian Population

Objective: instability in the organization and expression of the genetic material has been hypothesized as the basic mechanism of ageing. Aim of this study was to quantify the effect of ageing on spontaneous micronuclei (MN) frequency in peripheral blood lymphocytes. Method: analysis of Yugoslavian population sample (164 tested individuals, age 0–62 years) has performed by application of cytokinesis-block technique (CB). Results: there was an increase of MN frequency with age, from newborns to 40-year-old persons. The total average of MN frequency per 1000 analyzed binuclear cells amounts to 8.03 ± 0.42, with variation from 0 to 26 MNs. In a sample of 29 newborns the recorded average MN frequency was 6.91 ± 0.81, while among 69 persons 25–39 years old, the MN frequency was 9.16 ± 1.00. The lowest average MN frequency, however, was noted in the sample of 34 tested individuals 40 to 62 years of age. Conclusion: an increase with age in MN frequency has been observed in samples of studied individuals from newborns to 40-year-old persons. A decrease of MN frequency in older groups could be explained by a gradual decrease of proliferative cell capacities.     

Baseline and therapy-induced chromosome damages in peripheral blood lymphocytes of breast cancer patients assessed by the micronucleus assay

Purpose: Radiotherapy (RT) alone or in combination with chemotherapy (CT) leads nearly always to increase of DNA damage in cancer patients. The purpose of this study was to determine the variability rate and individual sensitivity of breast cancer (BC) patients to the applied RT and RT in combination with CT. Methods: The analysed sample included 30 women with histologically confirmed BC. The frequency of micronuclei (MN) was estimated in peripheral blood lymphocytes (PBL) by using the cytokinesis-block micronucleus (CBMN) assay before the administered therapy and one month later. Results: The mean therapy-induced MN value was significantly higher (p < 0.001) compared with mean baseline MN. Both therapies (RT and combined RT+CT) significantly increased the MN frequency in patients' lymphocytes (p<0.001), but without significant differences in the therapy-induced MN frequency between these two groups (p > 0.05). The administered therapy induced significant difference in cell kinetics (p < 0.05). The results showed a wide range of inter-individual variability in both baseline and the therapy-induced MN frequency. Conclusion: The applied therapies increased the MN frequency in PBL in BC patients, and the presented data indicate absence of synergistic effect of these two therapies. None of the variation factors (age, smoking and therapy type) had influence on the noticed variability.