Genetic and Biochemical Factors Related to the Risk and Disability Progression in Multiple Sclerosis

Sclerosis multiplex (multiple sclerosis, MS) is a chronic autoimmune inflammatory disease of the central nervous system. The immune regulatory defects lead to the process of inflammation and neurodegenerationthat results in the deterioration of neurological functions. It is still unclear as to why MS is so devastating and rapidly progressive in one patient and less so in another. It is known that the etiopathogenesis of MS is very complex, and many factors can be involved in the risk and character of the disease and its progression. In this chapter, we discuss the general molecular and cellular mechanisms of action of genetic and biochemical factors that are related to immune system regulation and thus can be connected to the individually varying risk and disability progression of MS. We found that gene variants of the gene polymorphism rs6897932 in interleukin 7 receptor α chain gene rs10735810 in vitamin D receptor gene and HLA-DR and HLA-DQ genes as well as the serum level of vitamin D are associated with MS risk or disability progression in Central European Slovak population

Forebrain Ischemic Stroke and the Phenomenon of Ischemic Tolerance: Is Homocysteine Foe or Friend?

Hyperhomocysteinemia (hHCy) is a recognized comorbid risk factor of human brain stroke. We overview here the recent data on the homocysteine (Hcy) metabolism and on the genetic and metabolic causes of hHCy‐related neuropathologies. In context of our results which detected an increased oxidative stress in hyperhomocysteinemic rats, we discuss here the role of free radicals in this disorder. Brain ischemia‐reperfusion causes delayed neuronal death. Ischemic tolerance evoked by preconditioning (IPC) represents a phenomenon of central nervous system (CNS) adaptation to any subsequent ischemia. The paper describes changes in the mitogen‐activated protein kinases (MAPKs) protein pathways, and apoptotic markers were used to follow the degeneration process. Our studies provide evidence for the interplay and tight integration between extracellular signal‐regulated kinase (ERK) and p38 MAPKs signaling mechanisms in response to the hHCy and also in association with brain ischemia/IPC challenge. Recognition of the effects of risk factors in the ischemic tolerance would lead to improved therapeutics, especially the brain tissue

Sedimentological record of flood events from years 2002 and 2007 in the Danube River overbank deposits in Bratislava (Slovakia)

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Response of the Danube River floodplain to flood events during 2002–2007 period

The relationship between floods and their geomorphic effect is discussed in this article. Almost every flood event is registered in overbank alluvia. We investigated sediment structures and textures as a response to three flood events occurred during 2002–2007 period on the Danube River floodplain in Bratislava. The change in sedimentation is the effect of floodwater flow energy changeability in the channel and floodplain. Generally, three main phases of energy flow changes of floods are recognised and thus the complete flood record can be expressed as the set of three layers. We also analysed conditions of the overbank sedimentation based on the shape and size of sedimented particles. Results show a relatively high variability of sedimentation processes during floods. The total amount of new overbank sediment accumulated in the 2002–2007 period, its texture characteristics and spatial distribution do not depend only on flood discharge, but also on the drainage basin sources of floodwater and sediment

Histone Hyperacetylation as a Response to Global Brain Ischemia Associated with Hyperhomocysteinemia in Rats

Epigenetic regulations play an important role in both normal and pathological conditions of an organism, and are influenced by various exogenous and endogenous factors. Hyperhomocysteinemia (hHcy), as a risk factor for several pathological conditions affecting the central nervous system, is supposed to alter the epigenetic signature of the given tissue, which therefore worsens the subsequent damage. To investigate the effect of hHcy in combination with ischemia-reperfusion injury (IRI) and histone acetylation, we used the hHcy animal model of global forebrain ischemia in rats. Cresyl violet staining showed massive neural disintegration in the M1 (primary motor cortex) region as well as in the CA1 (cornu ammonis 1) area of the hippocampus induced by IRI. Neural loss was significantly higher in the group with induced hHcy. Moreover, immunohistochemistry and Western blot analysis of the brain cortex showed prominent changes in the acetylation of histones H3 and H4, at lysine 9 and 12, respectively, as a result of IRI and induced hHcy. It seems that the differences in histone acetylation patterns in the cortical region have a preferred role in pathological processes induced by IRI associated with hHcy and could be considered in therapeutic strategies

The Molecular and Cellular Effect of Homocysteine Metabolism Imbalance on Human Health

Homocysteine (Hcy) is a sulfur-containing non-proteinogenic amino acid derived in methionine metabolism. The increased level of Hcy in plasma, hyperhomocysteinemia, is considered to be an independent risk factor for cardio and cerebrovascular diseases. However, it is still not clear if Hcy is a marker or a causative agent of diseases. More and more research data suggest that Hcy is an important indicator for overall health status. This review represents the current understanding of molecular mechanism of Hcy metabolism and its link to hyperhomocysteinemia-related pathologies in humans. The aberrant Hcy metabolism could lead to the redox imbalance and oxidative stress resulting in elevated protein, nucleic acid and carbohydrate oxidation and lipoperoxidation, products known to be involved in cytotoxicity. Additionally, we examine the role of Hcy in thiolation of proteins, which results in their molecular and functional modifications. We also highlight the relationship between the imbalance in Hcy metabolism and pathogenesis of diseases, such as cardiovascular diseases, neurological and psychiatric disorders, chronic kidney disease, bone tissue damages, gastrointestinal disorders, cancer, and congenital defects