Zhang M, Zhang Y, Niu M, Zhu Y, Tong S, Kou X
College of Sports Medicine, Wuhan Sports University, Wuhan 430079, China.
Hubei Key Laboratory of Exercise Training and Monitoring, Wuhan 430079, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2023 Aug 20;43(8):1268-1278. doi: 10.12122/j.issn.1673-4254.2023.08.02.
To investigate the effect of 8-week dihydromyricetin (DHM) treatment on motor ability of mice with MPTP/probenecid-induced Parkinson's disease (PD) and explore the molecular mechanism.
Sixty C57BL/6 mice were randomized into the control group, PD model group, PD+DHM group and PD+NEC-1 group (=15). In the latter 3 groups, the mice were treated with 25 mg·kg·d MPTP and 250 mg·kg·d probenecid twice a week for 5 weeks to establish PD models; DHM (100 mg·kg·d) was administered 5 times a week via gavage for 8 weeks and NEC-1 (6.25 mg·kg·d, twice a week) via intraperitoneal injection for 5 weeks. The changes in motor function of the mice were assessed, and the expressions of TH, GFAP and Iba-1 in the substantia nigra were detected with immunofluorescence assay; serum levels of IL-1β and LDH were detected using ELISA. The mRNA expressions of TNF-α and IL-6 were determined with RT-PCR, and the expressions of TH and proteins associated with pyroptosis, neuroinflammation, necroptosis and autophagy in the striatum were detected using Western blotting. MPP +-activated Bv-2 cells were treated with different concentrations of DHM or 3-MA, and the expressions of proteins associated with autophagy and NLRP3 were detected using Western blotting; PI staining was used to detect cell necroptosis.
The PD mouse models showed significantly reduced TH-positive cells and TH protein expression ( < 0.001). DHM obviously ameliorated motor deficits and TH loss in PD mice, increased TH expression (=0.0023), decreased α-syn levels ( < 0.001), lowered the protein expressions of GFAP (=0.045) and Iba-1 ( < 0.001) and the mRNA and protein levels of TNF-α (=0.0015) and IL-6 ( < 0.001), and increased IL-4 level ( < 0.001). The 8-week DHM treatment significantly suppressed pyroptosis and necroptosis and activated autophagy in the striatum of the PD mice. In MPP +-induced Bv-2 cells, DHM treatment effectively reversed autophagy impairment and inhibited NLRP3 and TNF-α, IL-6 and IL-1β release, and the anti--inflammatory effects of DHM was obviously blunted by 3-MA.
DHM can improve motor function of PD mice probably by activating autophagy to inhibit pyroptosis and necroptosis and reduce neuroinflammation.
探讨8周二氢杨梅素（DHM）治疗对MPTP/丙磺舒诱导的帕金森病（PD）小鼠运动能力的影响，并探究其分子机制。
将60只C57BL/6小鼠随机分为对照组、PD模型组、PD+DHM组和PD+NEC-1组（每组15只）。后3组小鼠每周两次给予25mg·kg·d MPTP和250mg·kg·d丙磺舒，连续5周以建立PD模型；DHM（100mg·kg·d）每周灌胃5次，持续8周，NEC-1（6.25mg·kg·d，每周两次）腹腔注射5周。评估小鼠运动功能变化，采用免疫荧光法检测黑质中TH、GFAP和Iba-1的表达；采用ELISA检测血清IL-1β和LDH水平。用RT-PCR测定TNF-α和IL-6的mRNA表达，用Western印迹法检测纹状体中TH及与焦亡、神经炎症、坏死性凋亡和自噬相关蛋白的表达。用不同浓度的DHM或3-MA处理MPP+激活的Bv-2细胞，用Western印迹法检测与自噬和NLRP3相关蛋白的表达；用PI染色检测细胞坏死性凋亡。
PD小鼠模型中TH阳性细胞和TH蛋白表达显著降低（<0.001）。DHM明显改善了PD小鼠的运动功能障碍和TH缺失，增加了TH表达（=0.0023），降低了α-突触核蛋白水平（<0.001），降低了GFAP（=0.045）和Iba-1（<0.001）的蛋白表达以及TNF-α（=0.0015）和IL-6（<0.001）的mRNA和蛋白水平，并增加了IL-4水平（<0.001）。8周的DHM治疗显著抑制了PD小鼠纹状体中的焦亡和坏死性凋亡并激活了自噬。在MPP+诱导的Bv-2细胞中，DHM处理有效逆转了自噬损伤并抑制了NLRP3以及TNF-α、IL-6和IL-1β的释放，且DHM的抗炎作用明显被3-MA减弱。
DHM可能通过激活自噬来抑制焦亡和坏死性凋亡并减轻神经炎症，从而改善PD小鼠的运动功能。
