Cystathionine-beta-synthase (CBS) is an enzyme that catalyzes the first step of the transsulfuration pathway, from homocysteine to cystathionine, and in which variations are associated with human hyperhomocysteinemia and homocystinuria.
The aim of this study was to determine the effect of whole eggs and egg components (i.e., egg protein and choline) with respect to 1) homocysteine balance and 2) the hepatic expression and activity of betaine-homocysteine S-methyltransferase (BHMT) and cystathionine β-synthase (CBS) in a folate-restricted (FR) rat model of hyperhomocysteinemia.
NaHS adminstration restored the decreased levels of H<sub>2</sub>S and polysulfides with a concomitant increase in the activity of cystathionase (CSE) and cystathionine β-synthase (CBS) in the brain regions of HHcy animals.
Although hyperhomocysteinemia (HHcy) occurs because of the deficiency in cystathionine-β-synthase (CBS) causing skeletal muscle dysfunction, it is still unclear whether this effect is mediated through oxidative stress, endoplasmic reticulum (ER) stress, or both.
To study Hyperhomocysteinemia (HHcy)-induced epigenetic modifications as potential mechanisms of blood retinal barrier (BRB) dysfunction, retinas isolated from three- week-old mice with elevated level of Homocysteine (Hcy) due to lack of the enzyme cystathionine β-synthase (<i>cbs<sup>-/-</sup></i> , <i>cbs<sup>+/-</sup></i> and <i>cbs<sup>+/+</sup></i> ), human retinal endothelial cells (HRECs), and human retinal pigmented epithelial cells (ARPE-19) treated with or without Hcy were evaluated for (1) histone deacetylases (HDAC), (2) DNA methylation (DNMT), and (3) miRNA analysis.
Three index patients with hyperhomocysteinemia and ocular anomalies were screened for cystathionine beta synthase (CBS) and methylenetetrahydrofolate reductase (MTHFR) polymorphisms.
We studied the effect of HHcy on PCs and its role in vascular repair in severe HHcy (∼150 μM), which was induced in cystathionine-β synthase heterozygous mice fed a high-methionine diet for 8 weeks.
Mild (22 µmol/L) and moderate (88 µmol/L) HHcy were induced in cystathionine β-synthase wild-type (Cbs(+/+)) and heterozygous-deficient (Cbs(-/+)) mice by a high-methionine (HM) diet.
Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) and cystathionine β-synthase (CBS) genes, involved in the intracellular metabolism of homcysteine, can result in hyperhomocysteinemia.
Deficiency in cystathionine beta synthase (CBS) enzyme sometimes leads to hyperhomocysteinemia/homocystinuria, conditions often associated with mental retardation (MR).
We established a novel atherosclerosis-susceptible mouse model with both severe HHcy and hypercholesterolemia in which the mouse cystathionine beta-synthase (CBS) and apolipoprotein E (apoE) genes are deficient and an inducible human CBS transgene is introduced to circumvent the neonatal lethality of the CBS deficiency (Tg-hCBS apoE(-/-) Cbs(-/-) mice).
In humans, severe hyperhomocysteinemia due to genetic alterations in cystathionine beta-synthase (Cbs) or methylenetetrahydrofolate reductase (Mthfr) results in neurological abnormalities and premature death from vascular complications.
Genetic background conversion ameliorates semi-lethality and permits behavioral analyses in cystathionine beta-synthase-deficient mice, an animal model for hyperhomocysteinemia.
The aim of the present study was to analyze the modifications of redox state in the liver of heterozygous cystathionine beta synthase-deficient mice, a murine model of hyperhomocysteinemia.
As hyperhomocysteinemia due to cystathionine beta synthase deficiency is associated with a decreased expression of paraoxonase-1, a major anti-atherosclerotic component secreted by the liver, we aimed to analyze the expression of paraoxonase-1 and cystathionine beta synthase in Down syndrome fetal liver by quantitative real-time reverse transcriptase-polymerase chain reaction.
However, folate deficiency, either associated or not associated with the thermolabile mutation of the N(5,10)-methylenetetrahydrofolate reductase, and vitamin B(6) deficiency, perhaps associated with cystathionine beta-synthase defects or with methionine excess, are believed to be major determinants of the increased risk of cardiovascular disease related to hyperhomocysteinemia.