Ricardo Junqueira Del Carlo

Cerebral ischemia causes muscle atrophy and motor incoordination in animals, impairing motor performance. Thus, the objective of the present study was to analyze the motor performance and histomorphometry of the biceps brachii, soleus, and tibialis anterior muscles of rats submitted to a treadmill training program after induction of cerebral ischemia by the transient occlusion of the middle cerebral artery (MCAO). To do so, twenty-four 30-day-old Wistar rats were utilized. The exercises were performed for 6 weeks on a leveled treadmill, for 30 minutes/day, 5 days a week, at a controlled speed of 8m/min, and the MCAO surgery took place for 60 minutes. The animals were divided into the following experimental groups: SC (n = 6): control animals that underwent false surgery (operation without the induction of cerebral ischemia) and did not exercise (sedentary); CEA (n = 6): control animals exercised on the treadmill after the false surgery; SI (n = 6): sedentary ischemic animals; IEA (n = 6): animals exercised on the treadmill after the induction of cerebral ischemia. The type-II fibers atrophy in muscle soleo was observed in groups CEA (5125.63 ± 158.83) and SI (4982.38 ± 248.16) when compared to the SC (5927.98 ± 106.17) and IEA (6526.73 ± 195.08) groups. It is concluded that the low intensity physical exercise performed on the treadmill for six weeks after the induction of cerebral ischemia by OMCA, promoted a decrease in the atrophy of muscles important of the ischemic animals, benefiting their motor performance.

Physical exercise is a known preventive and therapeutic alternative for several cerebrovascular diseases. Therefore, the objective of the present study was to evaluate the motor performance and histomorphometry of the biceps brachii, soleus, and tibialis anterior muscles of rats submitted to a treadmill training program prior to the induction of cerebral ischemia via occlusion of the middle cerebral artery (OMCA). A total of 24 Wistar rats were distributed into four groups: Sham-Sed: sedentary control animals (n=6), who underwent sham surgery (in which OMCA did not occur); Sham+Ex: control animals exercised before the sham surgery (n=6); I-Sed: sedentary animals with cerebral ischemia (n=6); and I+Ex: animals exercised before the induction of ischemia (n=6). The physical exercise consisted of treadmill training for five weeks, 30 min/day (5 days/week), at a speed of 14 m/min. The results showed that the type-I fibers presented greater fiber area in the exercised ischemic group (I+Ex: 2347.96±202.77 µm2) compared to the other groups (Sham-Sed: 1676.46±132.21 µm2; Sham+Ex: 1647.63±191.09 µm2; I+Ex: 1566.93±185.09 µm2; P=0.0002). Our findings suggested that the angiogenesis process may have influenced muscle recovery and reduced muscle atrophy of type-I fibers in the animals that exercised before cerebral ischemia.

The aim of this study was to analyse the density of astrocytes and neurons in the motor areas of the cortex, striatum and hippocampus of rats that performed exercise before or after cerebral ischemia. A total of 36 Wistar rats were separated into two groups: One that was subjected to Middle Cerebral Artery Occlusion (MCAO) and the other that underwent surgical access in the absence of ischemia. Both groups were subdivided into: Animals that underwent exercise prior to MCAO and sham surgery (AI and AC, n = 12); animals that underwent exercise after MCAO and sham surgery (DI and DC, n = 12); and animals that did not undergo exercise (SI and SC, n = 12). The brains of mice were sectioned and stained by the Nissl method for staining of neurons and the astrocytes were labeled by immunohistochemistry with glial fibrillary acidic protein. Physical training was conducted after the surgery for 6 weeks (30 min/day), 5 days per week. The animals exercised before cerebral ischemia showed greater density of neurons in the striatum, in the apex of the dentate gyrus of the hippocampus, in the motor cortex contra lateral to the lesion and more astrocytes in the motor cortex of the cerebral hemispheres compared with the untrained group (p