ABSTRACT
Alzheimer's disease, a neurodegenerative disease, is one of the most common causes of dementia if elderly people worldwide. Alzheimer's disease leads to the alienation of individuals and their exclusion from social and professional life. It is characterized mainly by the degradation of memory and disorientation, which occurs as a result of the loss of neuronal structure and function in different brain areas. In recent years, more and more attention has been paid to use in the treatment of natural bioactive compounds that will be effective in neurodegenerative diseases, including Alzheimer's disease. G. biloba L. and its most frequently used standardized extract (EGb 761), have been used for many years in supportive therapy and in the prevention of cognitive disorders. The paper presents an overview of reports on the pathogenesis of Alzheimer's disease, as well as a summary of the properties of G. biloba extract and its effects on the possible pathogenesis of the disease. By exploring more about the pathogenesis of the disease and the benefits of G. biloba extract for patients with Alzheimer's disease, it will be possible to create an individualized therapeutic protocol to optimize the treatment.
ABSTRACT
Although glioblastoma multiforme (GBM) is a widely researched cancer of the central nervous system, we still do not know its full pathophysiological mechanism and we still lack effective treatment methods as the current combination of surgery, radiotherapy, and chemotherapy does not bring about satisfactory results. The median survival time for GBM patients is only about 15 months. In this paper, we present the epidemiology of central nervous system (CNS) tumors and review the epidemiological data on GBM regarding gender, age, weight, height, and tumor location. The data indicate the possible influence of some anthropometric factors on the occurrence of GBM, especially in those who are male, elderly, overweight, and/or are taller. However, this review of single and small-size epidemiological studies should not be treated as definitive due to differences in the survey methods used. Detailed epidemiological registers could help identify the main at-risk groups which could then be used as homogenous study groups in research worldwide. Such research, with less distortion from various factors, could help identify the pathomechanisms that lead to the development of GBM.
ABSTRACT
Extracellular matrix (ECM) molecules that are released by neurons and glial cells form perineuronal nets (PNNs) and modulate many neuronal and glial functions. PNNs, whose structure is still not known in detail, surround cell bodies and dendrites, which leaves free space for synapses to come into contact. A reduction in the expression of many neuronal ECM components adversely affects processes that are associated with synaptic plasticity, learning, and memory. At the same time, increased ECM activity, e.g., as a result of astrogliosis following brain damage or in neuroinflammation, can also have harmful consequences. The therapeutic use of enzymes to attenuate elevated neuronal ECM expression after injury or in Alzheimer's disease has proven to be beneficial by promoting axon growth and increasing synaptic plasticity. Yet, severe impairment of ECM function can also lead to neurodegeneration. Thus, it appears that to ensure healthy neuronal function a delicate balance of ECM components must be maintained. In this paper we review the structure of PNNs and their components, such as hyaluronan, proteoglycans, core proteins, chondroitin sulphate proteoglycans, tenascins, and Hapln proteins. We also characterize the role of ECM in the functioning of the blood-brain barrier, neuronal communication, as well as the participation of PNNs in synaptic plasticity and some clinical aspects of perineuronal net impairment. Furthermore, we discuss the participation of PNNs in brain signaling. Understanding the molecular foundations of the ways that PNNs participate in brain signaling and synaptic plasticity, as well as how they change in physiological and pathological conditions, may help in the development of new therapies for many degenerative and inflammatory diseases of the brain.
