Exercise in an islet-transplanted non pro marathon runner : effects on training, autoimmunity and metabolic profile

Type 1 diabetes mellitus (T1DM) is a chronically progressive autoimmune disease in which the adverse immune response is induced and promoted by the interaction of genetic and environmental factors. Recent studies have suggested that physical exercise may interfere with immune system function even at low intensity and duration. Here, an islet-transplanted T1DM patient (M, 44yrs) has been longitudinally monitored for autoimmunity markers, metabolic profile and physical performance, being himself a nonpro marathon runner, over a 7-year period from the islet allograft. Given his discontinuous story of training (because of injuries, medical issues etc), we identified 4 phases throughout this period, lasting ca 2 years each, characterized by rest and training, alternatively. Administration of an ad hoc regime of training (supervised interval training) showed an improvement in glycolsylated hemoglobin (HbA1c -9.2%, p<.05), C-reactive protein (-16.6%, p<.05) and a decrease of insulin treatment (from 4-8 to 4-6 U/die) during the 2nd phase with respect to the 1st phase of rest (recovery after allograft). In the 3rd phase (post-injury resting), Hb1Ac increased by 13.3% (p<.05 vs 2nd phase). In the 4th phase, exercise training was accompanied by an amelioration of Hb1Ac of 22% respect to the 3rd phase. Insulin units diminished dramatically with respect to the 1st phase (2-3 U twice a week), and so did the autoimmunity markers (antiGAD Ab from 0.5 to 0.0 AU; antiINS Ab from 6.6 to 1.6 AU). Race time during competition improved by 10.5% as compared with the 2nd phase of training (p<.05). Also in the 4th phase, aerobic-, anaerobic thresholds and heart rates resulted significantly higher than the previous phases (p<.05). Altogether, these data suggest that the alternation of detrimental metabolic and autoimmunity profiles may be associated with the interleaving of training/resting periods, evoking a potential role for exercise in a positive immunomodulation of system functions against T1DM progression and inflammation.