Is low ratio of S-adenosylmethionine to S-adenosylhomocysteine associated with vitamin deficiency in Brazilian pregnant women and newborns?
Lower maternal cobalamin concentrations are associated with higher tHcy and lower SAM:SAH in newborns. Because SAM:SAH is closely linked with the activity of numerous enzymatic methylation reactions, these results suggest that methylation could be impaired in cobalamin-deficient pregnant women and their newborns.
Although PDH suppression substantially alters central carbon metabolism, the data indicate that rapid cell proliferation occurs independently of PDH activity. Our findings reveal that this central enzyme is essentially dispensable for growth and proliferation of both primary cells and established cell lines. We also identify the compensatory mechanisms that are activated under PDH deficiency, namely scavenging of extracellular lipids and lipogenic acetyl-CoA production from reductive glutamine metabolism through IDH1.