Increased energy expenditure and activated beta 3-AR-cAMP-PKAsignaling pathway in the interscapular brown adipose tissue of 6-OHDA-induced Parkinson's disease model rats
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
Authors: Lian, Hui; Zhou, Li; Zhang, Yang; Song, Yan-Hai; Zhang, Yi-Min; Cao, Zheng-Hao; Wang, Zhi-Yong
Abstract
To explore the possible mechanism of weight loss in Parkinson's disease (PD). Bilateral injections of 6-hydroxydopamine (6-OHDA) into substantia nigra (SN) were performed to induce the PD model rats. The rotarod test, food intake, body weight, and interscapular brown adipose tissue (IBAT) weight were recorded 6 weeks postoperation. HE staining was performed to observe the morphology of multilocular adipose cells in IBAT. Immunohistochemistry and western blot were used to determine the protein levels of tyrosine hydroxylase (TH) in the SN, and the levels of uncoupling protein 1 (UCP1), peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1 alpha), phosphorylated-hormone sensitive lipase (p-HSL), HSL, TH, beta 3-adrenergic receptor (beta 3-AR), cyclic adenosine monophosphate (cAMP), and protein kinase A (PKA) in IBAT. After treatment with 6-OHDA for 6 weeks, 6-OHDA rats exhibited decreased TH expression in SN accompanied with shortened staying time on the rotating rod. This motor impairment paralleled with no significant alteration in body mass, IBAT weight, and food intake until the end of the experimental protocol. However, the decreasing diameter of the single fat vesicle in IBAT was observed in the 6-OHDA group. Meanwhile, compared with the control group, the protein expression of UCP1, PGC-1 alpha, p-HSL, TH, beta 3-AR, cAMP, and PKA in IBAT were increased significantly in the 6-OHDA group, whereas no obvious change in the expression of HSL. The present study suggested an increased energy expenditure and activation of the beta 3-AR-cAMP-PKA signaling pathway in the IBAT after the destruction of the dopamine system in the SN of the rat.
EphA1 Activation Induces Neuropathological Changes in a Mouse Model of Parkinson's Disease Through the CXCL12/CXCR4 Signaling Pathway
MOLECULAR NEUROBIOLOGY
Authors: Ma, Jianjun; Wang, Zhidong; Chen, Siyuan; Sun, Wenhua; Gu, Qi; Li, Dongsheng; Zheng, Jinhua; Yang, Hongqi; Li, Xue
Abstract
There is increasing evidence that EphA1 is involved in the function and development of the central nervous system, especially in neuroinflammation. It has been found to affect the disease progression of Alzheimer's disease (AD) by regulating the neuroinflammatory process. Neuroinflammation has always been regarded as the mechanism of the development of Parkinson's disease (PD) and possible therapeutic targets. Therefore, it is worth studying whether EphA1 has a potential therapeutic value for PD. The purpose of this study is to investigate the effect of EphA1 in mice and PD cell models and its mechanism. In this study, we verified the difference in expression of EphA1 and the effect and mechanism of EphA1 on neuropathological changes through Parkinson's patient samples, Parkinson's mice model, and Parkinson's model prepared from SH-SY5Y cells in vitro. EphA1 was highly expressed in the substantia nigra (SN) region of Parkinson mice and the Parkinson cell model, while the expression of tyrosine hydroxylase (TH) in the SN region of Parkinson mice was significantly reduced. After silenced EphA1 in the SH-SY5Y cell PD model, the expression levels of alpha-synuclein, inflammatory factors, and microglia-activated chemokine decreased. The co-immunoprecipitation experiment proved that EphA1 overexpression could promote the binding of CXCL12 and CXCR4. However, after silenced EphA1 and CXCL12 at the same time, the above effects brought by silenced EphA1 were suppressed. The same result appeared in mice with PD. EphA1 improves the inflammatory responses and neuropathological changes of the PD model in vivo and in vitro through the CXCL12/CXCR4 signaling pathway.