1. Endocrine Secretory Reserve and Proinsulin Processing in Recipients of Islet of Langerhans Versus Whole Pancreas Transplants
- Author
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Christian Toso, Thierry Berney, Laurianne Giovannoni, Philippe Morel, Nabeel M. Elkhafif, Sophie Borot, Sandrine Demuylder-Mischler, and Domenico Bosco
- Subjects
Blood Glucose ,Male ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Islets of Langerhans Transplantation ,chemistry.chemical_compound ,0302 clinical medicine ,Insulin-Secreting Cells ,Insulin ,Original Research ,Proinsulin ,0303 health sciences ,geography.geographical_feature_category ,C-Peptide ,ddc:617 ,C-peptide ,Middle Aged ,Islet ,Female ,Pancreas Transplantation ,hormones, hormone substitutes, and hormone antagonists ,Adult ,endocrine system ,medicine.medical_specialty ,030209 endocrinology & metabolism ,Pancreas transplantation ,digestive system ,03 medical and health sciences ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,medicine ,Humans ,Pathophysiology/Complications ,030304 developmental biology ,Advanced and Specialized Nursing ,geography ,business.industry ,nutritional and metabolic diseases ,medicine.disease ,Transplantation ,Cross-Sectional Studies ,Diabetes Mellitus, Type 1 ,Endocrinology ,chemistry ,Basal (medicine) ,business - Abstract
OBJECTIVE β-Cells have demonstrated altered proinsulin processing after islet transplantation. We compare β-cell metabolic responses and proinsulin processing in pancreas and islet transplant recipients with respect to healthy control subjects. RESEARCH DESIGN AND METHODS We studied 15 islet and 32 pancreas transplant recipients. Islet subjects were subdivided into insulin-requiring (IR-ISL, n = 6) and insulin-independent (II-ISL, n = 9) groups. Ten healthy subjects served as control subjects. Subjects were administered an intravenous arginine stimulation test, and insulin, C-peptide, total proinsulin, intact proinsulin, and proinsulin fragment levels were determined from serum samples. Acute insulin response (AIR) and proinsulin processing rates were calculated. RESULTS We found that basal insulin and C-peptide levels were higher in the pancreas group than in all other groups. II-ISL patients had basal insulin and C-peptide levels similar to healthy control subjects. The IR-ISL group had significantly lower AIRs than all other groups. Basal processing rates were higher in the pancreas and II-ISL groups than in healthy control subjects and the IR-ISL group. After arginine stimulation, all groups had elevated processing rates, with the exception of the IR-ISL group. CONCLUSIONS Our data suggest that II-ISL transplant recipients can maintain basal metabolic parameters similar to healthy control subjects at the cost of a higher rate of proinsulin processing. IR-ISL transplant recipients, on the other hand, demonstrate both lower insulin response and lower basal rates of proinsulin processing even after arginine stimulation.
- Published
- 2013