EFFECT OF IRON ON BONE TISSUE METABOLISM AND THYROID FUNCTION IN CHILDREN LIVING ON RADIOLOGICALLY CONTAMINATED TERRITORIES SINCE THE ChNPP ACCIDENT

OBJECTIVE

identification of clinical and metabolic characteristics of osteogenesis and factors affecting bone mineral density (BMD) in children living in radioactively contaminated territories (RCT) after the ChNPP accident for the use of therapeutic and preventive measures aiming to reduce the incidence of disorders.

MATERIALS AND METHODS

Children aged 4 to 18 years old (n = 539) were involved in the study within 4 age groups, namely under 7 years old, 7-10 years old, 10-14 years old, older than 14 years old. Studied parameters in children with a reduced BMD (85-65 relative units and under 65 relative units) were estimated vs. the normative BMD (100-85 relative units) cases. Diagnosis of osteopenia and osteoporosis in children was established according to the BMD T-index. Family history of the relatives of children was studied. Body weight at birth, fractures of the long bones, complaints of osalgia, jaw anomalies, dental caries, presence of obesity, and hypermobility syndrome (HMS) were assessed. Peripheral blood biochemical tests were performed featuring the serum total protein, alkaline phosphatase (APh), calcium, vitamin D, creatinine, serum iron (SI), ferritin, cortisol, pituitary thyroid-stimulating hormone (TSH), and free thyroxine (FT4) assay. BMD was measured and radiation doses in children were reconstructed.

RESULTS

BMD depended on the age of children. A direct correlation was established between the cholelithiasis and urolithiasis incidence (р < 0.01), cancer and endocrine diseases (р < 0.05) in the relatives of children that had BMD under 65 relative units. Dental caries developed more often (р < 0.05), while obesity was less frequent (р < 0.05) in the subjects with BMD < 65 relative units. A direct correlation was established between the level of serum creatinine and BMD (р < 0.01), and there was an inverse correlation between the serum APh level and BMD (р < 0.001).Every third child had a vitamin D deficiency. Fractures of long bones and increased content of SI and TSH were characteristic for the children having got osteopenia (BMD within 85-65 relative units), while besides a predisposition to bone fractures the higher levels of SI, APh, cortisol both with calcium deficiency were found in children with osteoporosis (BMD < 65 relative units) compared to the general group with a similar BMD. An increased incidence of HMS was characteristic too. Radiation doses in children with osteopenia were higher than in those with osteoporosis: (1.17 ± 0.09) mSv and (0.92 ± 0.06) mSv respectively (р < 0.05). No correlation was found between the radiation doses and clinical signs, blood biochemistry or BMD.

CONCLUSIONS

Study of the functional mechanisms of bone structures in children, depending on their metabolism, had made it possible to reveal the factors that affect bone formation in children living in RCT after the ChNPP accident, and to form the population groups for the timely application of therapeutic and preventive measures aiming to reduce the incidence of disorders of musculoskeletal system.

Impact of chronic blood viral infection on lymphocyte telomere length in Chornobyl clean-up workers in a remote period after radiation exposure

OBJECTIVE

To assess whether telomere length in lymphocytes of Chornobyl clean up workers at a late period 30 years after the exposure to ionizing radiation is influenced by a chronic blood viral infection and to determine role of viral carriage in cellular senescence.

PATIENTS AND METHODS

Study group included 70 Chornobyl cleanup male workers 30 years after exposure {doses of external exposure (602.67 ± 114.19) mSv (M ± m); age (59.75 ± 0.82) yrs}. Relative telomere length (RTL) was analysed by fluorescence in situ hybridization and flow cytometry, immune cell subsets by standard combinations of monoclonal antibodies (CD45/14, CD3/19, CD4/8, CD3/HLADR, CD3/16/56, TCRγδ) and flow cytometry; antiviral immunity was performed determining the chronic phase antibodies to viruses: Hepatitis C (HCV), Cytomegalovirus (CMV), Toxoplasma gondii (TOX), Herpes simplex (HSV) and Epstein Barr virus (EBV VCA IgG and EBV NA IgG). The object of the study was peripheral blood (PB) of clean up workers.

RESULTS

RTL changes were associated at the group level with the carrier state of the viral infection. RTL shortening was demonstrated as a significant difference between the groups (M ± SD) (HCV negative 15.27 ± 3.35, HCV posi tive 13.09 ± 3.05, p < 0.08, n = 12/52) or as a tendency (CMV negative 15.99 ± 5.41, CMV positive 14.86 ± 3.46 (M ± SD), p < 0.57, n = 11/53; HSV negative 17.01 ± 1.35, HSV positive 14.79 ± 3.80, p < 0.33, n = 13/51; TOX neg ative 15.94 ± 3.41, TOX positive 14.30 ± 3.81(M ± SD), p < 0.23, n = 27/37). These unidirectional changes can be associated with premature early cell aging of immune cells. To the contrary the significant RTL elongation was demonstrated in the group of EBV NA chronic carriers (EBV NA negative 11.25 ± 3.02 (M ± SD), EBV NA positive 16.15 ± 3.08 (M ± SD), p < 0.001, n = 15/49).

CONCLUSION

The study confirmed the assumption on a relationship existing between the telomere length, chronic viral infection and late effects in immune cells. The changes of telomeres length on the background of immune dys function may be a sign of cellular aging, and concomitant chronic blood viral infection such as Hepatitis C, Epstein Barr viruses carriage could form a background for an error prone DNA reparation system as a factor of accumulation of pathological conditions, including malignant transformation.

Peculiarity of prooxidant-antioxidant balance indicators in patients with nonalcoholic fatty liver disease who have been exposed to ionizing radiation due to the Chornobyl NPP accident

OBJECTIVE

To define the features of prooxidant antioxidant balance in patients with nonalcoholic fatty liver disease who have been exposed to radiation as a result of the Chornobyl accident.

METHODS

using Indicators characterizing the processes of oxidative modification of macromolecules by blood lev els of compounds with isolated double bonds (CIDB), diene conjugates (DC) oxodiene conjugates (ODC), secondary products of lipid peroxiodation reacting with thiobarbituric acid, products of oxidative modification of proteins in blood serum by levels of neutral and basic 2,4 dynitrofenilhidrazones, superoxide dismutase and catalase content in erythrocytes and ceruloplasmin in plasma were determined for the diagnosis of oxidative stress. The factor of antiox idant state was calculated.

RESULTS

In the absence of differences between the ratios between the primary and intermediate products of lipids peroxidation increasing relative content of DC and ODC in patients with nonalcoholic steatohepatitis (NASH), which suffered radiation exposure, was found compared with patients without nonalcoholic fatty liver disease (NAFLD) and NASH patients, who had no history of radiation exposure. This may be a manifestation of insignificant activation of lipid peroxidation and disturbance of LPO products transformation at different stages. In irradiated steatohepato sis (SH) patients, unlike SH patients who have not undergone radiation exposure,, the proportionalityof lipid perox idation products between the content of izopropanol phase lipid extracts of blood was violated, and Spearman cor relation coefficients between CIDB and DC and DC and ODC did not exceed the limits average values. In the group of patients with SH who suffered from radiation exposure level CIDB was slightly higher compared with patients with NASH. Regardless of whether there was a history of radiation exposure, the level of oxidative protein modification (OMB) products in NASH patients was higher compared with patients with SH, but the difference reached significant values only in the subgroup of non irradiated patients with NASH by 2.4 dinitrophenilhydrazones of neutral charac ter. Mean values ??of catalase activity in patients with NASH also exceeded the corresponding values of SH patient. The average values of the factor of antioxidant status in patients with both SH and NASH subjected to radiation exposure, were lower than in the corresponding subgroups of non irradiated patients by 29 and 21%, respectively.

CONCLUSION

Existing dismetabolic disorders may contribute to the development of endogenous intoxication and deepening of pathological changes in the liver of NAFLD patients from SH to NASH.

Lymphocytosis in children after the Chornobyl NPP accident

OBJECTIVE

To establish the sources of lymphocytosis in children living in ecologically unfavorable conditions after the Chornobyl Nuclear Power Plant accident aiming the high risk group formation for oncohematological diseases among the children's population.

MATERIALS AND METHODS

The 226 children with lymphocytosis were surveyed. The of child's life history and kind of somatic morbidity were considered. Quantitative and qualitative parameters of blood cells, biochemical indices including immunoglobulins (A, M, G), circulating immune complexes, phagocytosis indices were assayed.

RESULTS

Children with lymphocytosis were more often born with a high bodyweight, they demonstrated manifestations of constitutional lymphatism, lymphadenopathy and more often had respiratory infections. Quantitative and qualitative changes of hemopoietic elements depended on a type of a disease. Activation of lipid peroxidation, dysimmunoglobulinemia and increased level of circulating immune complexes were revealed. Treatment and preventive actions promoted normalization of hemogram indices in 58% of children surveyed.

CONCLUSIONS

The abnormalities in immune indices, activated lipid peroxidation in membranes of hemopoietic elements, and manifestations of granulocytopoietic disorders were established it children with lymphocytosis. Therefore these children can be attributed tot the group of increased risk on oncohematological disease.