The metabolic connection between diabetes mellitus and autoimmune hypothyroidism

It is supposed that there is a connection between diabetes mellitus (DM) and autoimmune hypothyroidism (AIH). The aim of this study was to compare some biochemical blood parameters in experimental DM and AIH. The experiments were carried out on outbred white rats. DM was induced by feeding animals with a high-fat diet and a single injection of streptozotocin (35 mg/kg). AIH was induced by three subcutaneous injections of thyroglobulin (100μ/rat) and Freund's adjuvant. For the first injection complete adjuvant, for the second and third treatments, incomplete adjuvant was used on the sixth and seventh days after the first injection. Results show that level of insulin does not change but the level of thyroxine decreases slightly in diabetic rats. In rats with AIH the insulin level was sharply increase, but thyroxine level sharply decreased. Almost all blood parameters in rats with DM and AIH (some organic metabolites, activity of enzymes) were changed unidirectional. Analogical blood parameters shift in both diseases shows the metabolic ways of both autoimmune diseases intersect. This phenomenon should be taken in attention to understand the etiology of DM and AIH.