GPC4 and Hyperglycemia: Moreover, there was a specific relationship between glycaemia and glypican-4 level observed by Ussar et al. [2] in an animal study: random-fed blood glucose and insulin measurements revealed that high-fat diet-fed mice were still able to maintain normal glycemia and normal insulinemia, with much higher serum glypican-4 levels than control animals (with a standard diet), but markedly obese (ob/ob) mice had hyperglycaemia despite hyperinsulinemia, which was accompanied with reduced serum glypican-4 levels.