Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.5.7.1 (methylenetetrahydrofolate reductase)
 2,116 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Folate deficiency has been associated with chronic anticonvulsant therapy. Characterization of the effects of individual anticonvulsants has been undertaken. Chronic treatment of rats with sodium valproate caused a decrease in liver folate concentration with concomitant increases in brain and plasma folate concentrations. After several weeks, these trends were reversed and folate concentrations tended to normalize. Chronic valproate treatment affected the activities of folate-dependent one-carbon enzymes: Serine hydroxymethyltransferase activity in liver was increased; methylenetetrahydrofolate reductase activity in both brain and liver was decreased; and methyltetrahydrofolate:homocysteine methyltransferase activity in both brain and liver decreased initially but returned toward normal with continued treatment. Methionine adenosyltransferase activity in brain declined after several weeks of treatment but the concentration of S-adenosylmethionine in liver increased with chronic valproate treatment. These data are consistent with the hypothesis that the effects of anticonvulsants on folates are a consequence of the mechanism of action of the anticonvulsant.
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PMID:Effect of chronic valproate treatment on folate-dependent methyl biosynthesis in the rat. 308 64

The subcellular distributions of the enzymes associated with the methylation and cystathionine-synthesizing portion of the sulfur amino acid metabolic pathway have been determined in the occipital lobe of the rhesus monkey. 5-Methyltetrahydrofolate-homocysteine methyltransferase and 5, 10-methylenetetrahydrofolate reductase activities are located mainly in the soluble compartment. Serine hydroxymethyltransferase activity is located primarily in mitochondria. Cystathionine beta-synthase is a soluble enzyme with a significant component occluded within the nerve endings. Glycine, serine, and cystathionine increase per gram of tissue during development. Glycine and serine are approximately 30% occluded within the nerve endings. These data are consistent with a localization of sulfur amino acid metabolism that supports a differential compartmentation of potential neurotransmitter function and methylation function in the primate.
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PMID:Sulfur amino acid metabolism in the developing rhesus monkey brain: subcellular studies of the methylation cycle and cystathionine beta-synthase. 720 68