Effects of radical scavengers on the development of experimental diabetes.

The possible value of radical scavengers in the prevention of beta cell destruction was studied in two animal models of type I diabetes. Eight compounds were tested alone or in combinations. In the low-dose streptozotocin model treatment started 24 hr after the last injection of the beta cell toxin, in the BB rat daily administration was started at 50 days of age (i.e., 20-70 days before diabetes onset). No effect was seen in the low-dose streptozotocin model for 3-aminobenzamide, N-acetyl-DL-homocysteine thiolactone, ebselen, and butylated hydroxyanisole whereas partial suppression of hyperglycaemia was seen in mice receiving cysteamine. In BB rats diabetes development was delayed and partially suppressed by administration of ebselen plus vitamin E plus MaxEPA (fish lipid concentrate), but not when ebselen was replaced by nicotinamide. We conclude that the disease process is not readily modifiable by treatment with exogenous radical scavengers.