Pancreatic gangliosides delay the onset of insulitis and hyperglycaemia in the low-dose streptozotocin mouse model

Gangliosides have been shown to modulate autoimmune phenomena in experimental diabetes. The effects of a pancreatic ganglioside preparation or of a commercial brain ganglioside mixture on the insulitis and blood glucose levels in the low-dose streptozotocin mouse model of diabetes have been investigated. Fifty-five C57BL/6J male mice were grouped as follows: Group 1 (n = 20) was injected intraperitoneally with repeated low doses of streptozotocin; Group 2 (n = 10) received streptozotocin as above but was also injected with a pancreatic ganglioside preparation equivalent to 2 micrograms sialic acid 2 h before each streptozotocin dose; Group 3 (n = 15) received streptozotocin and brain-derived gangliosides in the same dose as that of pancreatic gangliosides; Group 4 (n = 10) consisted of normal animals. Half of the mice were killed on day 12 and the others on day 24 from the beginning of treatment. On day 12, among the streptozotocin-injected animals only those treated with pancreatic gangliosides remained normoglycaemic, whereas on day 24 all streptozotocin mice were hyperglycaemic. Such a result paralleled the data pertaining to insulitis scores. In conclusion, pancreatic gangliosides have a short-term protective role on the development of diabetes in the low-dose streptozotocin model, an effect therefore linked to tissue-related differences in the glycosphingolipid composition.