Ernst-Friedrich-Pfeiffer Memorial Lecture. New aspects of C-peptide physiology.
C-peptide is co-secreted with insulin and has generally been considered not to possess biological activity. However, several recent studies during the last five years have demonstrated that administration of C-peptide in physiological amounts to type 1 diabetes (IDDM) patients on a short term basis (1-3h) results in decreased glomerular hyperfiltration, augmented glucose utilization and improved autonomic nerve function. More prolonged administration (1-3 months) of C-peptide to IDDM patients is accompanied by improvements in both renal function (diminished microalbuminuria) and autonomic and sensory nerve function. Both in vitro and in vivo data indicate that C-peptide may have a role in the regulation of insulin secretion. C-peptide's mechanism of action is not known but it may be related to its ability to stimulate Na+, K(+)-ATPase, activity, probably by activating a receptor coupled to a pertussis toxin-sensitive G-protein with subsequent activation of Ca2(+)-dependent intracellular signaling pathways. In conclusion, the combined findings indicate that C-peptide is a biologically active hormone. The possibility that C-peptide therapy in IDDM patients may be beneficial should be considered.
Wahren
J
J
Department of Surgical Sciences, Karolinska Hospital, Stockholm, Sweden.
Johansson
B L
BL
D000419:Albuminuria / Q000188:drug therapy; D000595:Amino Acid Sequence; D002096:C-Peptide / Q000502:physiology*; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology; D003929:Diabetic Neuropathies / Q000188:drug therapy; D004789:Enzyme Activation / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007668:Kidney / Q000187:drug effects / Q000502:physiology; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000494:pharmacology; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
D002096:C-Peptide; D007328:Insulin; D010446:Peptide Fragments; D000254:Sodium-Potassium-Exchanging ATPase