C-peptide is a peptide chain produced when proinsulin breaks down to produce insulin. Its molar amount is equal to that of insulin, so it can be used as a substitute indicator for detecting insulin secretion. C-peptide is related to multiple intracellular signaling pathways in the cell. It is not only a biomarker for the diagnosis of non-diabetic hypoglycemia and insulinoma, but also related to the treatment and prognosis of various complications of diabetes. Creative BioMart Biomarker offers high quality detection service for C-peptide, ensuring high detection accuracy, reproducibility and efficiency.
The C-peptide is a peptide chain connecting the A chain and the B chain of insulin in proinsulin, and consists of 31 amino acids. Proinsulin is formed in the endoplasmic reticulum and forms two disulfide bonds between the A and B chains of insulin, and one disulfide bond in the A chain. During the formation of proinsulin, the C-peptide is essential for the correct folding of the two chains of insulin. Proinsulin is then secreted into the Golgi apparatus and packed into vesicles for release. Proinsulin is catalyzed by proinsulin converting enzyme and carboxypeptidase E in the vesicles to undergo proteolysis, producing equimolar amounts of C-peptide and insulin. After insulin and C-peptide are secreted from pancreatic β cells, insulin is largely eliminated in the liver, while the content of C-peptide hardly changes. In addition, because C-peptide has a longer half-life in the blood and has less hemolytic effect, C-peptide can be used as a substitute indicator of insulin secretion in clinical testing. At the same time, the determination of C-peptide can be used for the evaluation of hypoglycemia in non-diabetic patients and the diagnosis of insulinoma. The C-peptide may bind to the G protein-coupled membrane receptor on the membrane structure to increase the intracellular calcium ion concentration and subsequently activate multiple intracellular signaling pathways that depend on calcium ions. The intracellular signaling pathway that C-peptide participates in is related to the pathogenesis and treatment of diabetes. Therefore, C-peptide can be used not only as a biomarker for the diagnosis of non-diabetic hypoglycemia and insulinoma, but also as a treatment and prognostic indicator for various complications of diabetes.
Figure 1. Processing of the proinsulin prohormone (Yosten, 2015)
Plasma and serum C-peptide levels can be studied as a biomarker in researches related to diabetes mellitus, insulinoma, etc.
Creative BioMart Biomarker strictly controls each specific experimental step in the C-peptide detection procedure to ensure accurately quantify the level of C-peptide in each sample.
At Creative BioMart Biomarker, we offer C-peptide detection service which include several technical methods, you can communicate with our experts according to your research needs, and we will determine the final detection technical scheme based on the communication results. Please feel free to contact us, Creative BioMart Biomarker is here to offer you professional and thoughtful service.