Processes of adult neurogenesis can be influenced by environmental factors. Here, we investigated the effect of microwave radiation (MWR) on proliferation and cell dying in the rat rostral migratory stream (RMS) - a migration route for the neuroblasts of the subventricular zone. Adult and juvenile (two weeks old) rats were exposed to a pulsed-wave MWR at the frequency of 2.45 GHz for 1 or 3 h daily during 3 weeks. Adult rats were divided into two groups: without survival and with two weeks survival after irradiation. Juvenile rats survived till adulthood, when were tested in the light/dark test. Proliferating cells in the RMS were labeled by Ki-67; dying cells were visualized by Fluoro-Jade C histochemistry. In both groups of rats irradiated as adults we have observed significant decrease of the number of dividing cells within the RMS. Exposure of juvenile rats to MWR induced only slight decrease in proliferation, however, it strikingly affected cell death even two months following irradiation. In addition, these rats displayed locomotor hyperactivity and decreased risk assessment in adulthood. Our results suggest that the long-lasting influence of radiation is manifested by affected cell survival and changes in animals´ behavior., A. Raček, K. Beňová, P. Arnoul, M. Závodská, A. Angelidis, V. Cigánková, V. Šimaiová, E. Račeková., and Obsahuje bibliografii
Several neurodegenerative conditions, such as Alzheimer’s disease and Parkinson’s disease, or vascular dementia and cognitive impairment, are associated with mild hyperhomocysteinemia. Hyperhomocysteinemia is defined as an increas e of the homocysteine (Hcy) level beyond 10 μM. Although the adverse effect of Hcy on neurons is well documented, knowledge about the impact of this amino acid on glial cells is missing. Therefore, with the aim to evaluate the neurotoxic properties of Hcy on glial cells, we used a glioblastoma cell line as a study model. The viability of cells was assayed biochemically and cytologically. At a concentration around 50 μM in the culture medium D,L -Hcy induced cell death. It is noteworthy that Hcy induces cell death of human glial cells at concentrations encountered during mild hyperhomocysteinemia. Therefore, we propose that Hcy -induced impairment of neuronal functions along with damage of glial cells may contribute to the etiopathogenesis of neurodegenerative diseases associated with hyperhomocysteinemia., H. Škovierová, S. Mahmood, E. Blahovcová, J. Hatok, J. Lehotský, R. Murín., and Obsahuje bibliografii
The purpose of this study was to investigate the occurrence and time-course of apoptosis in soleus skeletal muscle during the first 48 hours of unloading. Fifty Charles River mice were randomly divided into five groups (n=10 each) according to the time of hindlimb suspension (HS). Mice we re suspended for 0 (Control), 6 (6HS), 12 (12HS), 24 (24HS), and 48 hours (48HS). Soleus muscle atrophy was confirmed by a significant decrease of 20 % in muscle-wet weight and of 5 % in the ratio protein concentration/muscle wet-weight observed after 48 hours of unloading. The apoptotic index, the AIF (apoptosis-inducing factor) and p53 expression presented th eir uppermost value (304 %, 241 % and 246 %, respectively) at 24HS, and were preceded by the highest activity of caspase-3 and -8 at 12HS (170 % and 218 %, respectively) and of Bax/Bcl-2 content at 6HS (160 %). There were no marked ultrastructural alterations until 24 hours of simulated weightlessness. Lysosomal autophagic activity and infiltration of phagocytic cells were observed at 24HS and 48HS and might have contributed to the degenerative changes noticed in both groups. Though not consistently supported by morphological evidences, the biochemical parameters sustain the concept that the occurrence of apoptosis parallels the soleus atrophic response in its early phase., R. Ferreira, M. J. Neuparth, R. Vittorino, H. J. Appell, F. Amado, J. A. Duarte., and Obsahuje bibliografii a bibliografické odkazy