Two major hypotheses have been expounded to explain the hyperproinsulinemia
in type 2 diabetes: the increased release of proinsulin might result from an intrinsic defect in proinsulin processing, leading to an increased release of immature insulin precursors and thus contributing to the impairment in [beta]-cell function in type 2 DM.
segregates young adult patients with newly diagnosed autoimmune (type 1) and non-autoimmune (type 2) diabetes.
is a common feature of the insulin resistance (IR) syndrome.
and proinsulin-to-insulin ratios in Swedish middle-aged men: association with glycemia and insulin resistance but not with family history of diabetes.
In this study, total proinsulin concentrations were in accord with previously published reports of 10% (proinsulin:insulin) for samples from persons without diabetes and 20% for patients with type 2 diabetes (24), with no samples displaying inappropriate hyperproinsulinemia (25).
A novel point mutation in the insulin gene giving rise to hyperproinsulinemia.
Increased secretory demand rather than a defect in the proinsulin conversion mechanism causes hyperproinsulinemia
in a glucose-infusion rat model of non-insulin-dependent diabetes mellitus.
However, in patients suffering from type I (10) or type II diabetes (11-13), familial hyperproinsulinemia (14,15), or insulinoma (16), the insulin concentration can be overestimated by the relatively high concentrations of proinsulin and conversion intermediates.
Two unrelated patients with familial hyperproinsulinemia due to a mutation substituting histidine for arginine at position 65 in the proinsulin molecule: identification of the mutation by direct sequencing of genomic deoxyribonucleic acid amplified by polymerase chain reaction.
Proinsulin radioimmunoassay in the evaluation of insulinomas and familial hyperproinsulinemia.
Proinsulin-like material is increased in clinical conditions such as insulinoma (6-9), familial hyperproinsulinemia (10-13), and non-insulin-dependent diabetes mellitus (NIDDM) (3,9,14-17).
Familial hyperproinsulinemia due to a proposed defect in conversion of proinsulin to insulin.