CBS promoter hypermethylation increases the risk of hypertension and stroke

OBJECTIVES: Cystathionine β-synthase is a major enzyme in the metabolism of plasma homocysteine. Hyperhomocysteinemia is positively associated with hypertension and stroke. The present study was performed to examine the possible effects of Cystathionine β-synthase promoter methylation on the development of hypertension and stroke. METHODS: Using quantitative methylation-specific PCR, we determined the Cystathionine β-synthase methylation levels in 218 healthy individuals and 132 and 243 age- and gender-matched stroke and hypertensive patients, respectively. The relative changes in Cystathionine β-synthase promoter methylation were analyzed using the 2-ΔΔCt method. The percent of the methylated reference of Cystathionine β-synthase was used to represent the Cystathionine β-synthase promoter methylation levels. RESULTS: In this study, the Cystathionine β-synthase promoter methylation levels of hypertensive and stroke participants were both higher than that of the healthy individuals (median percentages of the methylated reference were 50.61%, 38.05% and 30.53%, respectively, all p<0.001). Multivariable analysis showed that Cystathionine β-synthase promoter hypermethylation increased the risk of hypertension [odds ratio, OR (95% confidence interval, CI)=1.035 (1.025-1.045)] and stroke [OR (95% CI)=1.015 (1.003-1.028)]. The area under the curve of Cystathionine β-synthase promoter methylation was 0.844 (95% CI: 0.796-0.892) in male patients with hypertension and 0.722 (95% CI: 0.653-0.799) in male patients with stroke. CONCLUSION: Cystathionine β-synthase promoter hypermethylation increases the risk of hypertension and stroke, especially in male patients.

study of normobaric hyperoxia preconditioning on superoxide dismutase activity in the rat stroke model

Ischemic preconditioning [IPC] is an endogenous phenomenon that can induce ischemic tolerance [IT] in variety of organs such as brain. In this study, we examined the intermittent and prolonged normobaric hyperoxia [HO] on neurologic deficit scores, infarct volume, and superoxide dismutase activity. The rats were divided to four main groups. First two main groups were exposed with HO in prolonged [24h; PrHO] and intermittent [4hx6 days; InHO] groups and second two main group acted as controls, and were exposed to 21% oxygen in the same chamber [room air, RA] continuously [24h; PrRA] and discontinuously [4hx6 days InRA]. Each group subdivided to three subgroups. After 24 h, first subgroup were subjected to 60 minutes MCAO followed by 24 h of reperfusion. Then, IT induced by InHO and PrHO were measured by neurologic deficit scores and infarct volume. Second and third subgroups were called sham-operated and intact subgroups for assessment of the effect of HO on superoxide dismutase activity. Our findings indicate that InHO and PrHO are involved in the induction of IT. Pretreatment with InHO and PrHO reduced neurologic deficit scores and infarct volume significantly. InHO and PrHO increase superoxide dismutase activity significantly. Although further studies are needed to clarify the mechanisms of ischemic tolerance, InHO and PrHO seem to partly exert their effects via increase superoxide dismutase activity

Are the angiotensin-converting enzime gene and acticity risk factors for stroke?

O acidente vascular cerebral (AVC) é doença multifatorial em que fatores genéticos desempenham papel importante. Este estudo foi desenvolvido para verificar o polimorfismo do gene da enzima conversora da angiotensina (ECA) em pacientes turcos com AVC agudo e estabelecer se existe associação do gene I/D da ECA com parâmetros clínicos. O estudo foi realizado com 185 pacientes e 50 controles. A associação entre a distribuição alélica da inserção / deleção (I/D) do polimorfismo do gene da ECA foi estudada pela reação em cadeia da polimerase. A distribuição dos genótipos I/D do gene da ECA e suas freqüências não apresentaram significância estatística quando comparados os pacientes e controles. As freqüências dos alelos D foram 57,8% nos pacientes versus 53% nos controles e dos alelos I 42,2% versus 47% respectivamente. Antecedentes de hipertensão, AVC, doença renal, doenças cardíacas, idade, gênero, pressão arterial sistólica e diastólica e níveis de creatinina foram significantemente elevados no grupo dos pacientes. No entanto estes resultados quando comparados com a atividade e o polimorfismo do gene da ECA não apresentaram diferenças estatísticas entre o grupo de pacientes e controles. Nossos resultados sugerem que o polimorfismo do gene da ECA não é associado com a patogênese do AVC em paciente turcos.

Role of MTHFR C677T polymorphism in ischemic stroke.

BACKGROUND: Homozygosity for MTHFR C677T polymorphism can lead to significantly high homocysteine levels and hyperhomocysteinemia is an important risk factor for thrombotic events. AIMS: The aim was to determine role of MTHFR C677T polymorphism in North Indians with ischemic stroke. SETTINGS AND DESIGN: In a prospective study, the subjects of stroke were recruited from the neurology clinic of the hospital. Controls were healthy individuals from the Hematology clinic without any history of stroke. MATERIALS AND METHODS: Plasma homocysteine levels were measured by enzyme immuno assay method after 3 months of acute episode. Serum folate and Vitamin B12 levels were estimated by competitive inhibition radioassay. MTHFR polymorphism was detected by PCR-RFLP using Hinf I enzyme. Statistical analysis: The analysis of significance of results was done using SPSS software package. A p-value. RESULTS: Thirty-two acute ischemic stroke patients (aged 1-44 years) were studied. Fourteen (43.8%) had recurrent stroke. Nine (28%) had multiple infarcts. Four of 32 patients (12.5%) had high homocysteine levels. Three out of these 4 hyper-homocysteinemia patients were homozygous ( TT ) for MTHFR polymorphism (2 with recurrent stroke). Two of three homozygous cases with TT genotype had low serum folate. Five of 32 stroke cases (18.8%) were heterozygous ( CT ) genotype. CONCLUSIONS: Primary hyper-homocysteinemia appears to be an important risk factor for ischemic stroke in North Indians, most due to MTHFR C677T homozygosity. Folate levels may modify the presentation of the MTHFR TT genotype.