title: Does exercise pose a challenge to glucoregulation after clinical islet transplantation?
abstract: Islet transplantation (ITx) is effective in preventing severe hypoglycemia by restoring glucose-dependent insulin secretion in type 1 diabetes (T1D), but may not normalize glucose regulation. Studies suggest that physical activity plays a role in maintaining β-cell mass and function in individuals with type 2 diabetes and animal models of diabetes. This could indicate that physical activity plays a role in graft survival in ITx recipients. This review's objective is to assess current knowledge related to physical activity in ITx recipients. Responses to other challenges in blood glucose control (i.e., hypoglycemia) in human ITx recipients were examined to provide in-depth background information. To identify studies involving exercise in ITx recipients, a systematic search was performed using PubMed, Medline, and Embase, which revealed 277 English language publications. Publications were excluded if they did not involve ITx recipients; did not involve physical activity or hypoglycemia; or did not report on glucose, insulin, or counterregulatory hormones. During induced hypoglycemia, studies indicate normal suppression of insulin in ITx individuals compared with healthy non-T1D controls. Studies involving exercise in ITx animals have conflicting results, with time since transplantation and transplantation site (spleen, liver, kidney, peritoneal cavity) as possible confounders. No study examining blood glucose responses to physical activity in human ITx recipients was identified. A small number of induced-hypoglycemia studies in humans, and exercise studies in animals, would suggest that glucoregulation is greatly improved yet is still imperfect in this population and that ITx does not fully restore counterregulatory responses to challenges in blood glucose homeostasis.
authors.affiliation: a Augustana Faculty, University of Alberta., 4901 - 46th Avenue Camrose, AB T4V 2R3, Canada.
authors.forename: Deanna R
authors.initials: DR
authors.lastname: Funk
authors.affiliation: b Faculty of Physical Education and Recreation, University of Alberta. 1-059D, Li Ka Shing Centre for Health Research Innovation, Edmonton, AB T6G 2E1, Canada.
authors.forename: Normand G
authors.initials: NG
authors.lastname: Boulé
authors.affiliation: c Faculty of Medicine and Dentistry, Division of Endocrinology, University of Alberta. 2000 College Plaza 8215 112 Street, Edmonton AB T6G 2C8, Canada.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Senior
authors.affiliation: a Augustana Faculty, University of Alberta., 4901 - 46th Avenue Camrose, AB T4V 2R3, Canada.
authors.forename: Jane E
authors.initials: JE
authors.lastname: Yardley
mesh_terms: D000818:Animals; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000150:complications / Q000601:surgery*; D015444:Exercise; D006085:Graft Survival; D006801:Humans; D006943:Hyperglycemia / Q000453:epidemiology / Q000517:prevention & control*; D007003:Hypoglycemia / Q000453:epidemiology / Q000517:prevention & control*; D016381:Islets of Langerhans Transplantation / Q000009:adverse effects*; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control*; D012306:Risk; D016042:Transplantation, Heterotopic / Q000009:adverse effects*
keywords: aerobic exercise; carbohydrate metabolism; exercice aérobie; exercice physique; exercise; exercise metabolism; hormones; métabolisme des sucres; métabolisme énergétique