The mTOR pathway and transgenic animals with deletion of the TSC gene in the regeneration of the nervous system and selected models of sciatic nerve damage

Traumatic damage to the nervous system has been a common occurrence for years, reducing patients' quality of life. The mammalian target of rapamycin (mTOR) pathway plays a key role in nervous system physiology, including by controlling nerve cell survival and differentiation. Excessive activation of the mTOR pathway leads to an increase in cell cycle protein activity and apoptosis of nerve cells. Moreover, current findings suggest the involvement of the mTOR pathway in neuroplasticity. The use of transgenic animals with deletion of the TSC gene as well as various models of sciatic nerve damage, allows activation of the mTOR pathway. Currently, the results confirm that inactivation of point mutations in TSC-1 or TSC-2 genes, activates the canonical signaling pathway of the mTORC-1 complex, in turn, reactivation of the mTORC-1 pathway through the absence of the TSC-1 gene in mature neurons induces axonal regeneration. Dysfunction of the mTORC-1 pathway in Schwann cells (SC) inhibits myelination of nerve fibers. The aim of the present study is to understand the physiology and role of the mTOR pathway as well as to demonstrate the impact of TSC gene deletion in the regeneration of the nervous system. Current research on the activity of the mTOR pathway may provide new strategies to intensify peripheral nerve regeneration.

Bcl-2-proteins and neurotrophins as important factors for the survival of peripheral neurons in transgenic animals

Apoptosis is an orderly, active process with the activation of certain genes that allows the cell to follow the path of programmed death. During embryogenesis, programmed cell death templates are essential for the proper formation of organs and the functioning of the nervous system in the regression of primary or abnormal structures. Increased cell mortality in the mature nervous system can lead to various neurodegenerative diseases. For these reasons, the Bcl-2 protein family is being studied intensively in connection with the function of the nervous system. Programmed cell death (PCD) makes it possible to eliminate superfluous cells and thus contribute to the maintenance of homeostasis in the body. Malregulation of apoptosis is characteristic of tumour processes, degenerative changes and autoimmune diseases. Research into gene expression of pro- and anti-apoptotic proteins using knock-out technology is currently raising great hopes for the treatment of patients affected by neurodegenerative changes.

Cerebral metabolism of glucose and selected glucose transporters in neurodegenerative diseases

Cerebral glucose metabolism is an issue of researchers’ interest for a long time. Disturbed transport and metabolism of glucose in the brain lead to development of numerous neurological pathologies. Recently, a significant correlation between perturbed cerebral glucose metabolism and development of neurodegenerative diseases has been shown. Glucose, a monosaccharide, is the main source of energy for brain cells. Brain is the organ which is the most sensitive to changes in blood glucose level. Perturbed glucose transport leads to disorders of the central glucose metabolism. Neurodegenerative diseases are defined in the literature as progressive and irreversible degeneration of nerve tissue, causing cell death as a result of degenerative processes. The aim of this article is to discuss the physiology and the role of selected glucose transporters in the development of neurodegenerative diseases: expression of selected GLUT1 and GLUT3 transporters in Alzheimer's and Huntington's diseases. Understanding of the cerebral glucose metabolism may be a crucial factor in fight with central nervous system diseases.

Air pollution tolerance index and heavy metal bioaccumulation in selected plant species from urban biotopes

This research was carried out on plants Taraxacum officinale, Plantago lanceolata, Betula pendula and Robinia pseudoacacia growing in urban biotopes with different levels of heavy metal contamination in the city of Dąbrowa Górnicza (southern Poland). Based on the pollution index, the highest heavy metal contamination was determined in the site 4 (connected with industry emitters) and 6 (high traffic). The metal accumulation index (MAI) values ranged within the biotopes in Dąbrowa Górnicza between 7.3 and 20.6 for R. pseudoacacia, 4.71-23.1 for P. lanceolata, 4.68-28.1 for T. officinale and 10.5-27.2 for B. pendula. Increasing tendency in proline content in biotopes connected with high traffic was found in the leaves of investigated plants (except R. pseudoacacia). Similar tendency was observed for ascorbic acid content in the foliage of the plants as well as in T. officinalle in stands connected industrial emission. Non-protein thiols content increased especially in the leaves of R. pseudoacacia in biotopes with high traffic emissions as well as in T. officinale in stands connected with industry. The mean values of APTI (Air Pollution Tolerance Index) within the city of Dąbrowa Górnicza for investigated plants were found in the following ascending order P. lanceolata < R. pseudoacacia < B. pendula < T. officinale. Among the investigated plants B. pendula and T. officinale may be postulated as appropriate plants in urban areas with considerable soil and air contamination, especially with heavy metals. The results indicate that species deemed tolerant according to APTI are suitable plants in barriers areas to combat atmospheric pollution.