Lipophilic thiamine treatment in long-standing insulin-dependent diabetes mellitus.

Thiamine plays an important role in the regulation of glucose metabolism and pancreatic beta-cell functioning. A role for this vitamin in cellular glucose transport has been indicated in the literature. The aim of this study was to determine whether a lipophilic form of thiamine (benzoyloxymethyl-thiamine, BOM) was able to improve metabolic control in patients with long-standing insulin-dependent diabetes mellitus (type 1). A total of 10 children with type 1 diabetes of long duration (age 11.4 +/- 1.2 years, duration of the disease 4.5 +/- 0.7 years, means +/- SEM) were studied before and after treatment with BOM in a randomized double-blind and placebo-controlled study. Five patients were assigned to the BOM-treated group and five to the placebo-group. In all patients basal and glucagon-stimulated C-peptide secretion was undetectable. Thiamine status was assayed by measuring the plasma content of thiamine and its monophosphate form at entry and after 3 months of treatment. The blood HbA(1C) levels and the daily dose of insulin per kg body weight were assessed in both groups before treatment, after 1 month and 3 months of treatment, then 3 months following its suspension. The plasma content of thiamine + thiamine monophosphate in type 1 diabetic patients (35.3 +/- 3.6 pmol/mL) was significantly lower when compared with that measured in six age-matched normal subjects (53.2 +/- 2.3 pmol/mL, P < 0.05).