Motor behavioral abnormalities and histopathological findings in middle aged male Wistar rats inoculated with cerebrospinal fluid from patients with Amyotrophic Lateral Sclerosis

Abstract

• Middle-aged male rats infused with CSF mimic pathogenic mechanisms observed in ALS. • Infusion of human CSF from patients of ALS causes motor impairment in middle-aged animals. • CSF from patients of ALS is a tool to investigate the characteristics of the disease. Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease associated with loss of upper and lower motor neurons in the primary motor cortex and spinal cord, respectively. Motor deficits are the main clinical features observed in patients with the disease. However, it has been suggested that the presence of neurotoxic factors in the cerebrospinal fluid (CSF) from ALS patients causes loss of motor neurons. The present study investigated the motor and histopathological changes induced by intracerebroventricular (ICV) infusion of CSF from ALS patients in middle aged male Wistar rats. Middle aged male rats were divided into three groups: (1) control group, animals injected with artificial CSF solution; (2) N-ALS group, animals injected with CSF from volunteers without neurological disease; and (3) ALS group, animals inoculated with CFS from a patient with definite ALS. After surgical and infusion procedures, animals were evaluated in different motor tests (grip strength; catalepsy and open field tests). Moreover, animals’ spinal cords were histologically investigated. We observed that ALS-CSF infusion reduced grip strength and led to motor changes and reduction in the number of motor neurons and glial cells in thoracic and lumbar regions of spinal cord. However, CSF N-ALS caused reduction of nerve and glial cells in the thoracic but not in the lumbar region. Our data suggest that ALS-CSF is associated with neurodegenerative mechanisms observed in ALS pathology.