title: Neuroprotective Effect of Paeonol Mediates Anti-Inflammation via Suppressing Toll-Like Receptor 2 and Toll-Like Receptor 4 Signaling Pathways in Cerebral Ischemia-Reperfusion Injured Rats.
abstract: Paeonol is a phenolic compound derived fromPaeonia suffruticosaAndrews (MC) andP. lactifloraPall (PL). Paeonol can reduce cerebral infarction volume and improve neurological deficits through antioxidative and anti-inflammatory effects. However, the anti-inflammatory pathway of paeonol remains unclear. This study investigated the relationship between anti-inflammatory responses of paeonol and signaling pathways of TLR2 and TLR4 in cerebral infarct. We established the cerebral ischemia-reperfusion model in Sprague Dawley rats by occluding right middle cerebral artery for 60 min, followed by reperfusion for 24 h. The neurological deficit score was examined, and the brains of the rats were removed for cerebral infarction volume and immunohistochemistry (IHC) analysis. The infarction volume and neurological deficits were lower in the paeonol group (pretreatment with paeonol; 20 mg/kg i.p.) than in the control group (without paeonol treatment). The IHC analysis revealed that the number of TLR2-, TLR4-, Iba1-, NF-κB- (P50-), and IL-1β-immunoreactive cells and TUNEL-positive cells was significantly lower in the paeonol group; however, the number of TNF-α-immunoreactive cells did not differ between the paeonol and control groups. The paeonol reveals some neuroprotective effects in the model of ischemia, which could be due to the reduction of many proinflammatory receptors/mediators, although the mechanisms are not clear.
authors.affiliation: Graduate Institute of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan.
authors.forename: Wen-Yen
authors.initials: WY
authors.lastname: Liao
authors.affiliation: Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan.
authors.forename: Tung-Hu
authors.identifier: 0000-0002-9007-2547
authors.initials: TH
authors.lastname: Tsai
authors.affiliation: Graduate Institute of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan.
authors.forename: Tin-Yun
authors.initials: TY
authors.lastname: Ho
authors.affiliation: School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, Taichung 40402, Taiwan.
authors.forename: Yi-Wen
authors.identifier: 0000-0001-7204-8837
authors.initials: YW
authors.lastname: Lin
authors.affiliation: School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan.
authors.forename: Chin-Yi
authors.identifier: 0000-0003-1423-1283
authors.initials: CY
authors.lastname: Cheng
authors.affiliation: Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan; Graduate Institute of Integrated Medicine, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan; Department of Chinese Medicine, China Medical University Hospital, Taichung 40447, Taiwan; Research Center for Chinese Medicine and Acupuncture, China Medical University, Taichung 40402, Taiwan.
authors.forename: Ching-Liang
authors.identifier: 0000-0002-8187-4716
authors.initials: CL
authors.lastname: Hsieh