Association of environmental enrichment and locomotor stimulation in a rodent model of cerebral palsy: Insights of biological mechanisms.

Several physiotherapy approaches are used with different aims in the treatment of cerebral palsy (CP), such as the early stimulation and the locomotor training, but their biological effects, isolated or combined, are not completely known. In animals models, these strategies can be compared, with due translational restrictions, to the environmental enrichment (EE), that involves the enhancement of animal's physical and social environment, and locomotor stimulation (LS), that can be performed using the treadmill adapted for rats. This study was designed to describe which biological and functional mechanisms underlying rehabilitative process in clinical practice. Male rat pups were initially divided in two groups: control (healthy) and submitted to a CP model. Then, pups were divided in eight groups: CP, CPEE, CPLS, CPEELS and its respectively control groups. Functional outcomes were assessed at the postnatal day (P) 31 and P52. The tibialis anterior and soleus muscles, tibia bone parameters, the expression of synaptophysin in the primary motor cortex (M1) and ventral horn (VH) of the spinal cord, were evaluated. The association of therapies was able to improve the functional assessments and musculoskeletal parameters. Isolated therapies presented complementary benefits in CP, but the association of therapies proved to be a fundamental and effective strategy to functional recovery, besides alter positively all biological tissues evaluated in this study.