The Effects of Resistance Exercise Training on Insulin Resistance Development in Female Rodents with Type 1 Diabetes
Abstract
The etiology of insulin resistance (IR) development in type 1 diabetes mellitus (T1DM) remains unclear; however, impaired skeletal muscle metabolism may play a role. While IR development has been established in male T1DM rodents, female rodents have yet to be examined in this context. Resistance exercise training (RT) has been shown to improve IR and is associated with a lower risk of hypoglycemia onset in T1DM compared to aerobic exercise. Additionally, the molecular mechanisms mediating RT-induced improvements in insulin sensitivity remain unclear. Therefore, the purpose of this study was to investigate the effects of RT on IR development in female T1DM rodents. Forty Sprague-Dawley eight-week-old female rats were divided into four groups: control sedentary (CS; n=10), control trained (CT; n=10), T1DM sedentary (DS; n=10), T1DM trained (DT; n=10). Multiple low-dose Streptozotocin injections (20 mg/kg each day for seven consecutive days) were used to induce T1DM. Blood glucose levels were maintained in normal range (4-9mmol/L) with intensive insulin therapy (one implanted insulin pellet; 2IU/day). CT and DT underwent weighted ladder climbing 5 days/week for six weeks. Intravenous glucose tolerance tests (IVGTT) were conducted on all animals following the six-week period. Results demonstrate that DS animals exhibited significantly increased weekly blood glucose measures compared to all groups including DT (p