Tianqi pingchan granule promotes recovery of glymphatic system function in a rat model of l-DOPA-induced dyskinesia

Abstract

Background and aimTianqi Pingchan Granule (TPG), as a traditional Chinese medicine, is used in the treatment of Parkinson's disease. l-DOPA-induced dyskinesia (LID) is mentioned as a debilitating motor complication in the course of Parkinson's disease. The purpose of this study is to investigate the effects of TPG on LID via the pathway of the glymphatic system. Experimental procedureA rat model of LID was used in this study. The severity of LID was assessed by behavioural tests. Three doses of TPG were administered once a day for 3 weeks to investigate the role of TPG in behavioural characteristics of LID rats. The glymphatic function was evaluated by utilizing intracisternal infusion of a fluorescenttracer. The amyloid-β levels were measured by Enzyme-linked immunosorbent assay. The expression and distribution of, and GFAP were assessed using immunofluorescence. Results and conclusionDose-dependent effects of TPG in the 1behavioural characteristics were observed. Cortical and striatal influx cerebral spinal fluid tracer were reduced in LID rats with impaired AQP4 polarization. Amyloid-β, AQP4, and reactive astrogliosis was upregulated in LID rats. TPG administration increased cerebral influx of fluorescent tracer, restored polarized localization and expression of AQP4, and attenuated l-DOPA-induced amyloid-β deposits and astrogliosis. This study shows for the first time that glymphatic system function is impaired in LID and TPG attenuates abnormal involuntary movements in rats with LID by protecting the glymphatic system. Section1. Natural Products; 3. Dietary therapy supplements; 4. History, Philosophy and Social-Cultural aspects of Traditional Medicine. Taxonomy (classification by evise)identify the disease condition, the experimental approach.