Vitamin E and nicotinamide have similar effects in maintaining residual beta cell function in recent onset insulin-dependent diabetes (the IMDIAB IV study)

Abstract

Objective: Protection of residual beta cell function at the time of diagnosis of insulin-dependent diabetes mellitus (IDDM) by intensive insulin therapy and the addition of nicotinamide (NA) has been established. The objective of this study was to evaluate the effect of a free oxygen radical scavenger such as vitamin E (Vit E) on residual beta cell function and parameters of metabolic control in patients with recent onset IDDM undergoing intensive insulin therapy. Design: The effect of Vit E was compared with that of NA (control group) in a randomized multicentre trial. Methods: Eighty-four IDDM patients between 5 and 35 years of age (mean age 15.8Ϯ8.4 (S.D.) years) entered a one year prospective study. One group of patients (n=42) was treated with Vit E (15 mg/kg body weight/day) for one year; the other group (n=42) received NA for one year (25 mg/kg body weight/day). All patients were under intensive insulin therapy with three to four injections a day. Basal and stimulated (1 mg i.v. glucagon) C-peptide secretion, glycosylated haemoglobin and insulin dose were evaluated at diagnosis and at three-monthly intervals up to one year. Results: Preservation and slight increase of C-peptide levels at one year compared with diagnosis were obtained in the two treated patient groups. No statistically significant differences were observed in basal or stimulated C-peptide levels between the two groups of patients for up to one year after diagnosis. Glycosylated haemoglobin and insulin dose were also similar between the two groups; however patients receiving Vit E under the age of 15 years required significantly more insulin than NAtreated patients one year after diagnosis (P<0.04). Conclusions: Our data indicate that Vit E and NA possess similar effects in protecting residual beta cell function in patients with recent onset IDDM. Since their putative mechanism of protection on beta cell cytotoxicity is different, combination of these two vitamins may be envisaged for future trials of intervention at IDDM onset.

γ-Tocopherol Partially Protects Insulin-Secreting Cells against Functional Inhibition by Nitric Oxide

“…Furthermore, serum tocopherol levels were shown to be inversely correlated with the risk of developing type 1 diabetes mellitus in humans (51). In a one year prospective clinical trial, vitamin E was given to newly diagnosed type 1 diabetes mellitus patients receiving intensive insulin treatment (28). In this study, a comparison was made with nicotinamide, and it turned out that the radical scavenger vitamin E showed beneficial effects equal to nicotinamide in preserving ␤-cell function in terms of glycosylated hemoglobin and C-peptide levels, which were significantly improved compared to patients on intensive insulin therapy only (28).…”

“…In a one year prospective clinical trial, vitamin E was given to newly diagnosed type 1 diabetes mellitus patients receiving intensive insulin treatment (28). In this study, a comparison was made with nicotinamide, and it turned out that the radical scavenger vitamin E showed beneficial effects equal to nicotinamide in preserving ␤-cell function in terms of glycosylated hemoglobin and C-peptide levels, which were significantly improved compared to patients on intensive insulin therapy only (28). Our present results concur with these reports, in that we detected a partial (approx 50%) preventive effect of ␥-tocopherol, but not ␣-tocopherol, on RINm5F cells exposed to IL-1␤ or NO.…”

Is the process of beta-cell destruction in type 1 diabetes at time of diagnosis more extensive in females than in males?

“…The network includes registration of new cases (Eurodiab ACE) (ages 0 -15 years) and participation in clinical trials (IMDIAB) (ages 5-35 years) aimed at protecting residual b-cell function (6,7). Previous reports have focused on agebased differences in clinical presentation of type 1 diabetes (2,8,9), but data on sex-based effects on residual b-cell function and clinical presentation have not been reported.…”

The Role of Complementary and Alternative Therapies in Pediatric Diabetes

“…The investigators suggested combining the remedies for a possible synergistic effect; however, a control group of patients treated solely with insulin, as seen in earlier studies by the same group, was lacking in this trial. 16 In the IMDIAB IX study by Crino and colleagues, 17 discussed later in the section on vitamin E, children with new-onset type 1 diabetes were treated with either vitamin E or nicotinamide in addition to insulin for 2 years. No significant differences were found between c-peptide and HbA 1c levels, and the vitamin E group had a higher insulin requirement than the nicotinamide group.…”