The administration of adenosine together with homocysteine resulted in a dose-related elevation of cerebral S-adenosyl-Lhomocysteine without concomitant perturbation of S-adenosyl-Lmethionine levels. The adenosine + homocysteine treatment also decreased the incorporation of labjle and stable methyl groups into brain protrjins. Brain [ HI-phosphatidyl N,N-dimethylethanolamine and [ HI-phgsphatid...

BACKGROUND: Parkinson's disease (PD) is one of the prevalent debilitating neurodegenerative disor- ders. Accordingly, researchers are working on methods to modify PD progression. Previously, the neuro- protective effects of betaine, as a methyl donor agent in homocysteine metabolism, have been demonstrated in animal models of chronic cerebral hypoperfusion and memory deficits. OBJECTIVES: It wa...

The kinetic mechanism of the CheR methyltransferase, S-adenosyl-L-methionine (AdoMet): protein-L-glutamate O-methyltransferase (EC 2.1.1.24), from Salmonella typhimurium was investigated. Initial velocity, product inhibition, and binding studies were performed, and from the data obtained, it was determined that the mechanism of the reaction catalyzed by the enzyme is random. Initial velocity ra...

The effects of ethanol on epilepsy are very complex. Ethanol can have depressant as well as excitatory effect on different animal models of epilepsy. Systemic administration of homocysteine can trigger seizures. The aim of the present study was to examine the changes of total spectral power density after ethanol alone and together with homocysteine thiolactone in adult rats. Adult male Wistar r...

BACKGROUND Betaine (trimethylglycine) lowers plasma homocysteine, a possible risk factor for cardiovascular disease. However, studies in renal patients and in obese individuals who are on a weight-loss diet suggest that betaine supplementation raises blood cholesterol; data in healthy individuals are lacking. Such an effect on cholesterol would counteract any favourable effect on homocysteine. ...

BACKGROUND Elevated total homocysteine (tHcy), a risk factor for many chronic diseases, can be remethylated to methionine by folate. Alternatively, tHcy can be metabolized by other 1-carbon nutrients, ie, betaine and its precursor, choline. OBJECTIVE We aimed to assess the association between the dietary intakes of betaine and choline and the concentration of tHcy. DESIGN We conducted a cro...

BACKGROUND Accumulating data from epidemiological studies suggest that individuals with elevated blood levels of homocysteine have increased risks of cardiovascular disease. We reviewed the currently available evidence of an association between homocysteine and cardiovascular disease and examined whether the strength of the evidence varies according to study design. METHODS We used a computer...

OBJECTIVE To study the role of hyperhomocysteinemia in patients with intrauterine growth retardation. METHOD 76 patients with intrauterine growth retardation were studied and compared with 50 controls which included pregnant patients without any pregnancy complications. Fasting Plasma homocysteine levels were measured and statistical analysis using tests of significance and logistic regressio...

There is little doubt that elevation of plasma total homocysteine is associated with increased cardiovascular risk. Over the past 2 decades, many large prospective studies have established that hyperhomocysteinemia predicts for an increased relative risk of coronary events, stroke, venous thromboembolism, and death.1,2 Hyperhomocysteinemia also has been shown to produce abnormalities of vascula...

An in vitro RNA-synthesizing system was used to study the effects of S-adenosyl-L-homocysteine, S-adenosyl-L-methionine, and adenosine on the methylation and synthesis of single-stranded RNA by two different cytoplasmic polyhedrosis viruses.