title: C-peptide: much more than a byproduct of insulin biosynthesis.
abstract: OBJECTIVE
  During the past decade, numerous studies in both humans and animals have demonstrated that C-peptide, although not influencing blood sugar control, might play a role in preventing and potentially reversing some of the chronic complications of type 1 diabetes. The aim of this paper is to present an up-to-date review of C-peptide, focusing on its role in insulin biosynthesis and in the classification of diabetes mellitus, as well as its potential clinical applications.
  
  
  RESULTS
  The relevant literature cited in the MEDLINE database shows that the measurement of C-peptide production combined with screening for the presence of islet-cell and other autoantibodies seems to exert an important role in the accurate differentiation between patients with type 1 and type 2 diabetes. Also, both experimental and clinical data provide evidence suggesting that combined replacement of insulin and C-peptide has potential therapeutic value in patients with type 1 diabetes.
  
  
  CONCLUSIONS
  Further study in this area is warranted, but the findings that pancreas transplants promote the reversal of diabetic neuropathy and stabilization of diabetic retinopathy and that both pancreas and islet transplants lead to the reversal of diabetic nephropathy lend credence to the concept that combined replacement of insulin and C-peptide may more effectively mitigate the inexorable progression of diabetes-related complications.
authors.affiliation: Department of General Surgery, Rio de Janeiro State University, Rio de Janeiro, Brazil. Rmarques@uerj.br
authors.forename: Ruy G
authors.initials: RG
authors.lastname: Marques
authors.forename: Magali J
authors.initials: MJ
authors.lastname: Fontaine
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Rogers
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D016477:Artifacts; D002096:C-Peptide / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology / Q000502:physiology* / Q000627:therapeutic use; D020013:Calcium Signaling / Q000187:drug effects; D002648:Child; D048909:Diabetes Complications / Q000188:drug therapy; D003920:Diabetes Mellitus / Q000145:classification / Q000188:drug therapy / Q000378:metabolism* / Q000601:surgery; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000378:metabolism; D004353:Drug Evaluation, Preclinical; D004359:Drug Therapy, Combination; D006801:Humans; D007328:Insulin / Q000008:administration & dosage / Q000096:biosynthesis* / Q000627:therapeutic use; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008322:Mammals / Q000378:metabolism; D008875:Middle Aged; D016035:Pancreas Transplantation; D011384:Proinsulin / Q000096:biosynthesis; D011498:Protein Precursors / Q000096:biosynthesis; D011499:Protein Processing, Post-Translational
chemical_list: D002096:C-Peptide; D007328:Insulin; D011498:Protein Precursors; C013737:preproinsulin; D011384:Proinsulin