Neuroprotective effects of chloroquine on neurological scores, blood-brain barrier permeability, and brain edema after traumatic brain injury in male rats

Abstract

Background Traumatic brain injury (TBI) is one of the leading causes of death among young people worldwide. Chloroquine, an antimalarial drug, has been shown to easily cross the blood-brain barrier (BBB) and inhibit autophagy in a variety of disorders, including Alzheimer disease and brain ischemia. We investigated the effects of chloroquine on neuronal protection after induction of brain trauma in male rats. Methods A total of 120 male Wistar rats were treated with chloroquine at doses of 1.5, 3, and 6 mg/kg intraperitoneally after induction of diffuse TBIs. The veterinary coma scale was used to assess short-term neurological deficits. BBB disruption was evaluated using the Evans Blue dye method 6-hour post-injury. Vestibulomotor function was evaluated using the beam walk and beam balance methods. Histopathological changes in the brain tissue in different groups were evaluated using light microscopy and hematoxylin-eosin staining. Brain water and cerebrospinal fluid (CSF) contents of matrix metalloproteinase 9 (MMP-9) were assessed using the wet/dry method and enzyme-linked immunosorbent assay, respectively. Results The results showed that injecting chloroquine (3 and 6 mg/kg) 30 minutes after TBI significantly reduced brain edema and BBB disruption, and recovered neurological deficits post-TBI (P<0.01). Furthermore, CSF MMP-9 was significantly reduced after administration of 1.5 mg/kg chloroquine (P<0.01). Conclusion Chloroquine has neuroprotective effects in the brain, and thus, has the potential to mitigate the effects of brain trauma. It is possible that the anti-inflammatory and neurogenic effects of chloroquine are due to a decrease in MMP secretion in the CSF.

Keywords

• chloroquine
• brain trauma
• neural protection