Effects of liraglutide on inflammation and mitochondrial fusion/division in Parkinson' s disease model of mice induced by paraquat / 解剖学报

ABSTRACT

Objective To investigate the protective effect and mechanism of liraglutide on the paraquat (PQ)⁃ induced Parkinson's disease (PD) mouse model. Methods Totally 24 Kunming mice were randomly divided into control group, PQ group and PQ +liraglutide group, 8 mice in each group. PD model was established by intraperitoneal injection of PQ (10 mg/kg) for 5 consecutive days, and liraglutide (50 nmol/kg) was injected intraperitoneally for 7 consecutive days. The free⁃standing and locomotor activity of mice were measured by behavioral method. Immunofluorescence was used to observe the number of tyrosine hydroxylase (TH) and ionized calcium binding adaptor molecule 1 (Iba1) immunoreactive cells. Western blotting was used to detect the expression of protein TH, glial fibrillary acidic protein (GFAP), mitofusin⁃2 (Mfn2) and dynamin⁃related protein 1 (Drp1). Results The numbers of free⁃standing and locomotor activity numbers decreased significantly (P<0.01, P < 0.05) in PQ group compared with the control group, and the number of TH immunoreactive cells and TH protein expression in substantia nigra decreased significantly (P<0.01, P<0.01) compared with the control group, while the number of Iba1 immunoreactive cells and GFAP protein expression increased significantly (P<0.01, P<0.01) compared with the control group; the expression of Drp1 protein in PQ group was significantly higher than that in control group (P<0.05), while the Mfn2 protein expression decreased significantly (P<0.05) compared with the control group. After treatment with liraglutide, the number of TH positive cells in PQ + liraglutide group was significantly lower than that in control group (P<0.05); the numbers of free⁃standing and locomotor activity increased significantly (P<0.05, P<0.05) in PQ + liraglutide group compared with the PQ group, and the number of TH positive cells and expression of TH protein in PQ + liraglutide group were significantly higher than that in PQ group (P<0.01, P< 0.01); while the number of Iba1 positive cells and GFAP protein expression decreased significantly (P<0.01, P<0.05) compared with the PQ group; the Drp1 protein expression decreased significantly (P<0.01) compared with the PQ group, while the expression of Mfn2 protein in PQ + liraglutide group was significantly higher than that in PQ group (P<0.01). Conclusion Liraglutide has neuroprotective effect by reducing neuroinflammation in substantia nigra, regulating mitochondrial fusion and fission.