Acupuncture improves white matter perfusion and white matter integrity in vascular dementia rats: an MRI-based imaging study

Abstract

Background: White matter lesions induced by chronic cerebral hypoperfusion (CCH) are common pathological changes, and are associated with cognitive impairment in vascular dementia (VaD). It has been reported that acupuncture can improve cognitive deficits of VaD rats through increasing cortical cerebral blood flow and attenuating neuroinflammation. However, the effects of acupuncture on white matter perfusion and white matter structural integrity have been not investigated. Methods: VaD was induced by bilateral common carotid arteries occlusion (BCCAO)in Wistar rats. Morris water maze (MWM) was used to evaluated the spatial learning and memory of rats. Arterial spin labeling imaging (ASL) and diffusion tensor imaging (DTI) were performed to measure the cerebral blood flow and white matter integrity in corpus callosum, external capsule, internal capsule, optic nerve and optic tract. Pathological staining was also applied to detect the myelin loss and neuroinflammation.Results: BCCAO rats with declined cerebral blood flow exhibited significant worse MWM performance, and altered DTI parameters including decreased fractional anisotropy, elevated radial diffusivity and axial diffusivity in white matter regions.After acupuncture treatment at GV20 and ST36, cognitive dysfunction, disruption of white matter perfusion and integrity were reversed. Pathological results supported that acupuncture could attenuate the loss of myelin sheath and microglia activation. Conclusions:Our findings suggest that acupuncture treatment protects cognitive impairment of BCCAO rats through increasing subcortical white matter perfusion and improving white matter lesions.