title: Dietary microbial toxins and type 1 diabetes.
abstract: Toxins may promote type 1 diabetes by modifying or damaging the beta cell causing release of autoantigens. Streptomyces is a common soil bacterium that produces many toxic compounds. Some Streptomyces can infect vegetables, raising the possibility of dietary exposure to toxins. We aimed to identify toxins that erode cellular proton gradients in extracts of Streptomyces and infested vegetables and to establish the effect of low doses of these toxins on pancreatic islets in mice. The vacuolar ATPase inhibitors, bafilomycin and concanamycin, and the ionophore, nigericin, were identified in extracts from 4 of 13 Streptomyces isolated from infested potatoes and in potatoes themselves. Injection of bafilomycin A1 into mice impaired glucose tolerance, reduced islet size, and decreased relative beta cell mass. Thus, exposure to small quantities of bafilomycin in the diet may contribute to the cause of type 1 diabetes.
authors.affiliation: Monash University, Melbourne, Australia. mark.myers@med.monash.edu.au
authors.forename: M A
authors.initials: MA
authors.lastname: Myers
authors.forename: K D
authors.initials: KD
authors.lastname: Hettiarachchi
authors.forename: J P
authors.initials: JP
authors.lastname: Ludeman
authors.forename: A J
authors.initials: AJ
authors.lastname: Wilson
authors.forename: C R
authors.initials: CR
authors.lastname: Wilson
authors.forename: P Z
authors.initials: PZ
authors.lastname: Zimmet
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000032:analysis / Q000633:toxicity*; D003922:Diabetes Mellitus, Type 1 / Q000139:chemically induced* / Q000503:physiopathology; D004032:Diet; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005951:Glucose Tolerance Test; D051379:Mice; D008807:Mice, Inbred BALB C; D013302:Streptomyces / Q000737:chemistry*; D025262:Vacuolar Proton-Translocating ATPases / Q000037:antagonists & inhibitors
chemical_list: D001427:Bacterial Toxins; D004791:Enzyme Inhibitors; D025262:Vacuolar Proton-Translocating ATPases