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Ischemic stroke is a suddenly developing temporary or often permanent damage of the brain. Several candidate genes have been shown to have an impact in the pathogenesis of stroke. The aim of our study was to investigate the possible association between the C56G variant of the apolipoprotein A5 (APOA5) gene and ischemic stroke. PCR-RFLP assays were performed to detect the C56G alleles in 403 patients with classified stroke types and 171 controls. Triglyceride levels of subjects carrying 56G allele were elevated compared to the subjects with 56C allele in all stroke subgroups and in the controls. The serum total cholesterol levels did not differ between subjects with C or G alleles in each group. An accumulation of APOA5 56G allele was observed in the large-vessel associated stroke group compared to the healthy controls (10.9 vs. 5.6 %; p < 0.05), while its prevalence did not increase in any other stroke subgroups. Multivariate logistic regression analysis adjusted for differences in age, gender, BMI, serum total cholesterol levels, ischemic heart disease, hypertension, diabetes mellitus, smokingand drinking habits revealed that the APOA5 56G allele represents a susceptibility factor for large-vessel associated stroke (OR = 2.132 at 95 % CI; p < 0.05). The data presented here suggest that the 56G allele can confer risk exclusively for development of large-vessel associated stroke. Thereby, the 56G allele differs from the APOA5 T-1131C allelic variant, which has been previously identified as a risk factor for all subgroups of the stroke disease. [ABSTRACT FROM AUTHOR]

Ischemic demyelination in the white matter of the brain is a frequent clinical entity. In neuroimaging terms, it is referred to as leukoaraiosis (LA). LA can reflect a broad public health problem, which is caused by a cognitive impairment ranging from mild slowness of thinking to full-blown subcortical dementia. One-quarter of subjects aged 65 yr or over are affected by some degree of white matter changes. There are a number of genetic factors that can be associated with circulatory disturbances of the white matter of the brain. A slight chronic hypoperfusion or an endothelial dysfunction associated with unfavorable genetic variations such as methylenete-trahydrofolate reductase C677T variation and angiotensin-converting enzyme I/D polymorphism then may lead indirectly to a malfunction of the molecular cross-talk between the nucleus and the mitochondria. This results in a decrease in the production of energy in the glia cells and thereby the beginning of demyelination. From another aspect, the presence of either the apolipoprotein E2 or 4 alleles may cause an increased vulnerability to a slight chronic hypoperfusion of the white matter by reducing the range of mechanical and chemical flexibility of the glial cytoskeleton. In consequence of the chronic hypoperfusion, the functionally damaged kinesin protein gives rise also to the disturbances of the trafficking of the myelin basic protein mRNAs in the oligoden-drocytes. On the basis of the current knowledge on LA, this article suggests a hypothetical molecular bridge between the genetic, biochemical, and clinical processes. [ABSTRACT FROM AUTHOR]

The article focuses on the association suggested between the folic acid level and the occurrence of a congenital neuronal tube defect. There is a presumption that preconceptional folic acid supplementation can reduce the frequency of such a defect. In the United States, cereal food productions are fortified with folic acid as part of an intensive program of prevention.

Aims: Recent studies have started to elucidate the contribution of microbiome to the pathogenesis of multiple sclerosis (MS). It is also supposed, that neuropathological alterations might be associated with abnormal expression and regulatory function of antimicrobial peptides (AMPs), including defensins. It is in our interest to investigate the relevance of the single nucleotide polymorphisms (SNPs) of the DEFB1 gene and the copy number polymorphism of the DEFB4 genes in MS., Methods: DEFBI polymorphisms: c.-20G > A (rsl 1362), DEFB1 c.-44C > G (rsI 800972), DEFB1 c.-52G>A (rsl 799946), and the DEFB4 gene copy number were investigated in 250 MS patients The control patients comprised 232 age- and gender-matched healthy blood donors. The occurrence of the human β-defensin 2 peptide (hBD2) in the plasma of controls and patients-was determined by ELISA., Results: The DEFB1 c.-44C>G polymorphism the GG protective genotype was much less frequent among patients than among the controls. A higher frequency of a lower (<4) copy number of the DEFB4 gene was observed in the patients with MS as compared with the controls (43% vs. 28%, respectively). The median levels of the circulating hBD2 in the patients were 150.6 +/- 12.71 pg/ml vs. 262.1 +/- 23.82 pg/mI in the control group (p<0.0001). Our results suggest that β-defensins play role in the development of MS.

The present paper summarizes the possible roles of frequent and unfavourable genetic variants in cerebrovascular disorders, such as stroke and leukoaraiosis. It also approaches the topic theoretically from functional and mathematical points of view, which can help make the accumulating data on genetic variants more understandable. The interplay of an unfavourable genetic polymorphism and environmental clinical factors can result in a cerebrovascular disease or a state of vascular dementia. These constantly changing functional interactions need a highly specialised approach. There is, therefore, a great need to summarise the results on genetic polymorphisms concisely, and to discuss their special but shared features, which make their evaluation difficult with the methods used for the well-known Mendelian factors. The development of a correct approach to genetic polymorphisms may have a great impact on the understanding and prevention of cerebrovascular diseases.

An increasing body of evidence suggests that different genetic factors, such as angiotensin-converting enzyme (ACE) I/D, angiotensin II type-1 receptor (AT1R) A1166C, methylenetetrahydrofolate reductase (MTHFR) C677T and ENOS G894T variants are associated with an endothelial dysfunction (ED). EDs are relatively new phenomena that are presumed to contribute to vasoregulatory malfunctions at the small-vessel level. Ever more clinical observations indicate that the above genetic variants are also associated with cerebral small-vessel disorders. This article reviews the knowledge available on the roles of ED- associated genetic variants in cerebral circulatory disorders, and suggests that EDs can be causative factors for different common cerebral pathologies such as leukoaraiosis or/and small-vessel infarcts. Newly-developed drugs involving phosphodiesterase type-5 inhibitors, which improve the endothelial functions, may comprise a new approach to the treatment and prevention of small-vessel cerebral circulatory disorders.

Leukoaraiosis (LA), one of the most frequent causes of cognitive disturbances, is presumed to involve vascular demyelinization and cerebral small-vessel diseases. Although it has been suggested that the development of LA is associated with cerebral circulatory disturbances, the pathomechanism of this circulatory problem is not completely understood. Extensive debate is continuing as regards the detailed features of the circulatory disturbances in LA. An endothelial dysfunction may lead to breakdown of the blood-brain barrier, thereby resulting in chronic toxic edema in the perivascular areas. This can then cause the slow development of LA. Endothelial dysfunctions may also give rise to molecular events involving a shift in the O(2) and CO(2) trafficking system in the red blood cells, which will result in special complex microcirculation disturbances in the white matter of the brain; these molecular phenomena may therefore account for chronic slight hypoxia leading to the development of LA. This article discusses these hypothetical alternative molecular events behind LA. The review also illustrates how medicinal chemistry can offer new insight into a common, but still mysterious cerebral phenotype.

Introduction: Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C mutations, being considered unfavourable genetic factors by causing elevated serum homocysteine levels, may be risk factors for cardiovascular disorders, including ischaemic stroke. In this study, the role of these two mutations in ischaemic stroke was examined:, Patients and Methods: Genetic and clinical data were analysed of 122 ischaemic stroke patients and 102 control subjects with no lesions by neuroimaging., Results: Neither of the two MTHFR mutations alone was found to be a significant genetic risk factor for ischaemic stroke. However, at least one MTHFR 677T allele combined with at least one MTHFR 1298C allele significantly increased the risk of ischaemic stroke (adjusted odds ratio: 3.39; p < 0.001)., Conclusion: The synergistic effect between the two MTHFR mutations may represent a new genetic stoke risk factor.

Stroke is a very frequent entity. It is the third leading cause of death and the leading cause of adult disability in the developed world. At a population level, the common sporadic form of ischaemic stroke is underpinned by both environmental and genetic risk factors. Typically, in clinical practice, environmental risk factors such as hypertension, diabetes mellitus, smoking, alcohol consumption, and other factors, are usually considered to be more important than genetic factors. However, it is the interplay of both environmental and common genetic factors [such as the Leiden V, methylenetetrahydrofolate reductase C677T, apolipopotein E 4, endothelial nitric oxide synthase G894T, angiotensin-converting enzyme I/D and angiotensin II type 1 receptor A1166C mutations and polymorphisms] that leads to the development of ischaemic stroke. Indeed, a complex network of interactions between genetic factors and clinical risk factors can be supposed. This review evaluates the possible roles of gene-gene and gene-environment interactions concerning the above genetic factors in the evolution of ischaemic stroke and leukoaraiosis. A knowledge of the specific genetic patterns which are associated with a significant risk of ischaemic stroke or leukoaraiosis may also draw attention to a large population at an increased risk of circulatory disorders. This may facilitate the choice of more effective and specific prevention on the basis of the genotype.

Stroke is a common entity. It is the third leading cause of death and the leading cause of adult disability in the developed world. More than 110 heritable disorders, more than 175 genetic loci, and more than 2050 unique mutations predisposing to stroke are known. Although ischemic stroke can result from merely one gene defect (and a number of clearly defined mendelian hereditary disorders do lead to stroke), the interaction of unfavorable genetic factors such as the Leiden V, methylenetetrahydrofolate reductase (MTHFR) 677TT, apolipoprotein E (ApoE) 4, and angiotensin-converting enzyme (ACE) D/D genotypes, which alone are not major risk factors, can in specific patterns exert a synergistic effect on certain clinical risk factors. This chapter discusses how to evaluate these interactions and the interpretation of findings.