RGX-202 (β-GPA) is a creatine analog that alters skeletal muscle energy expenditure. It reduces cellular ATP, creatine, and phosphocreatine levels and stimulates AMP-activated protein kinase (AMPK), activating PPARγ coactivator 1α (PGC-1α).

The following animal groups were used for the experiment: (1) mice that were not subjected to injections (n = 10)—this group was used only for physiological tests and were not killed after the experiment;?(2) saline-treated mice (n = 8)—the volume of injections was 200 μL;?and (3) β-GPA-treated mice (n = 8)—concentration of β-GPA was 1 mg/kg/day.?The volume of injections was 200 μL.Injections were performed 3 times a week for 3 weeks.?The mice's weight and the total amount of consumed food and water were measured daily.?Once a week, a string test was performed.?Measurements of the oxygen consumption rates of live animals and the open field test were performed after the course of injections.?After 3 weeks, the mice were killed;?brain dissection was performed to extract the cortex and the ventral midbrain (VMB) for quantitative real-time polymerase chain reaction (qRT-PCR) analysis[2].