出版社：American Society for Biochemistry and Molecular Biology
摘要：We assessed whether patients with familial isolated vitamin E deficiency could discriminate between natural (RRR-) and synthetic (SRR-) stereoisomers of alpha-tocopherol labeled with six (d6) or three (d3) deuterium atoms, respectively. After oral administration of 20 mg of each of the stereoisomers, patients (seven) and controls (seven) had similar concentrations of both in chylomicrons, similar initial increases of both, and similar rates of decrease of d3-SRR-alpha-tocopherol in plasma. Patients and controls differed in their abilities to maintain plasma d6-RRR-alpha-tocopherol concentrations. Controls maintained plasma d6-RRR-alpha-tocopherol concentrations by preferentially secreting it in very low density lipoprotein (VLDL). Three of seven patients did not discriminate between the two stereoisomers and their plasma and lipoprotein d6-RRR-alpha-tocopherol concentrations declined rapidly. The remaining patients were intermediate between non-discriminators and controls in their ability to discriminate and maintain plasma d6-RRR-alpha-tocopherol concentrations. The degree of discrimination between the two stereoisomers in the patients was correlated with the age of onset of the neurologic disability (r2 = 0.64, P
