Description of Research Expertise

Dr. Rickels conducts patient-oriented diabetes research that aims at understanding the pathogenesis of various forms of diabetes and the in vivo mechanisms of new diabetes treatments. Dr. Rickels' research program is in particular focused on islet function and replacement in type 1 diabetes and pancreatogenic forms of diabetes such as cystic fibrosis-related diabetes. Dr. Rickels' studies involve methodologies for quantifying insulin and incretin secretion, insulin sensitivity, and glucose counterregulatory responses to hypoglycemia, and include oral glucose and mixed-meal tolerance tests, the frequently-sampled intravenous glucose tolerance test, the glucose-potentiated arginine test, and hyperinsulinemic euglycemic and hypoglycemic clamps incorporating stable glucose isotopes for determination of tissue specific insulin action and glucose counterregulatory mechanisms. Present work in type 1 diabetes is focused on understanding the mechanisms of defective glucose counterregulation and impaired awareness of hypoglycemia and novel approaches to the prevention or correction of hypoglycemia, including by beta-cell replacement (islet transplantation) therapy or artificial pancreas (closed-loop) technology. Present work in cystic fibrosis-related diabetes is directed at understanding the pathophysiology involved in the etiology of early defects in insulin secretion and the impact of different strategies for enhancing incretin effects on beta-cell function.

Selected Publications

Flatt AJ, Sheikh S, Peleckis AJ, Alvarado P, Hadjiliadis D, Stefanovski D, Gallop RJ, Rubenstein RC, Kelly A, Rickels MR: Preservation of beta-cell function in pancreatic insufficient cystic fibrosis with highly effective CFTR modulator therapy Journal of Clinical Endocrinology & Metabolism 109 (1): 151-160,2024.

Riddell MC, Li Z, Gal RL, Calhoun P, Jacobs PG, Clements M, Martin CK, Doyle FJ III, Patton SR, Castle JR, Gillingham MB, Beck RW, Rickels MR; T1DEXI Study Group: Examining the acute glycemic effects of different types of structured exercise sessions in type 1 diabetes in a real-world setting: The Type 1 Diabetes and Exercise Initiative (T1DEXI) Diabetes Care 46 (4): 704-713,2023.

Flatt AJ, Peleckis AJ, Dalton-Bakes C, Nguyen HL, Ilany S, Matus A, Malone SK, Goel N, Jang S, Weimer J, Lee I, Rickels MR: Automated insulin delivery for hypoglycemia avoidance and glucose counterregulation in long-standing type 1 diabetes with hypoglycemia unawareness Diabetes Technology & Therapeutics 25 (5): 302-314,2023.

Nyirjesy SC, Peleckis AJ, Eiel JN, Gallagher K, Doliba A, Tami A, Flatt AJ, De Leon DD, Hadjiliadis D, Sheikh S, Stefanovski D, Gallop R, D’Alessio DA, Rubenstein RC, Kelly A, Rickels MR: Effects of GLP-1 and GIP on islet function in glucose intolerant, pancreatic insufficient cystic fibrosis Diabetes 71 (10): 2153-2165,2022.

Flatt AJ, Chen E, Peleckis AJ, Dalton-Bakes C, Nguyen HL, Collins HW, Millar JS, Gallop RJ, Rickels MR: Evaluation of clinical metrics for identifying defective physiologic responses to hypoglycemia in long-standing type 1 diabetes Diabetes Technology & Therapeutics 24 (10): 737-748,2022.

Rickels MR, Eggerman TL, Bayman L, Qidwai JC, Alejandro R, Bridges ND, Hering BJ, Markmann JF, Senior PA, Hunsicker LG; Clinical Islet Transplantation Consortium: Long-term outcomes with islet-alone and islet-after-kidney transplantation for type 1 diabetes in the Clinical Islet Transplantation Consortium: The CIT-08 Study Diabetes Care 45 (12): 2967-2975,2022.

Kelly A, Sheikh S, Stefanovski D, Peleckis AJ, Nyirjesy SC, Eiel JN, Sidaye A, Localio R, Gallop R, De Leon DD, Hadjiliadis D, Rubenstein RC, Rickels MR: Effect of sitagliptin on islet function in pancreatic insufficient cystic fibrosis with abnormal glucose tolerance Journal of Clinical Endocrinology & Metabolism 106 (9): 2617-2634,2021.

Flatt AJS, Greenbaum CJ, Shaw JAM, Rickels MR: Pancreatic islet reserve in type 1 diabetes Annals of the New York Academy of Sciences 1495 (1): 40-54,2021.

Riddell MC, Li Z, Beck RW, Gal RL, Jacobs PG, Castle JR, Gillingham MB, Clements M, Patton SR, Dassau E, Doyle FJ, Martin CK, Calhoun P, Rickels MR: More time in glucose range during exercise days than sedentary days in adults living with type 1 diabetes Diabetes Technology and Therapeutics 23 (5): 376-383,2021.

Rickels MR, Norris AW, Hull RL: A tale of two pancreases: exocrine pathology and endocrine dysfunction Diabetologia 63 (10): 2030-2039,2020.

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Academic Contact Information

12-134 Smilow Center for Translational Research
3400 Civic Center Boulevard
Philadelphia, Pa 19104
Phone: 215-746-0025
Patient appointments: 800-789-7366