Electroacupuncture Ameliorates Collagen-induced Alzheimer’s Disease-like Brain Pathogenesis In Mice

ObjectiveDue to the unknown etiological cues, Alzheimer’s Disease (AD) is still in a hard way to be prevented or be cured. As the social aging problem is increasingly serious, AD has become a major hindrance in the economic boom of China. Considering inflammation has a imitated relationship with AD’s morbidity, we initially explore the possibility of injecting collagen emulsion in periphery to create the inflamed AD models. Hoping the inflammation related mechanism of AD could be revealed. A research proved that electroacupuncture (EA) could effectively against sepsis by modulating dopaminergic neuron to exert anti-inflammation effect, which has been published on Nature Medicine in 2014. On this basis, we hypothesized that EA reverses AD neurodegeneration through the dopaminergic neuron involved anti-inflammation pathway, which can also be a backward proof to clarify the inflammation related mechanism of AD.Material and MethodsA model of Alzheimer’s Disease-like brain pathogenesis was established by boost-injecting the emulsion which combined Type II collagen (CII) with complete Freund’s adjuvant (CFA) to inflame mouse’s hind paws for 2 weeks. EA (2/15HZ,1mA,15min for once) was performed at three acupoints-Dul4 (DaZhui), Du20 (BaiHui) and ST36 (ZuSanLi), daily from the first day of boosting injection, and the anatomy was conducted respectively after the first and second weeks. The analysis including Histochemical staining (HE and Silver staining), Immunohistochemistry (SABC method), Elisa, Western blot and RT-PCR to estimate the pathological changes in mice’brain, levels of inflammation, hypoxia, oxidative stress, mitochondrial biogenesis, autophagy and ubiquitination in periphery and CNS.ResultsCII-CFA induced peripheral inflammation could successfully establish the AD models, and EA successfully reversed the AD-like brain pathogenesis through the dopaminergic neuron involved anti-inflammation pathway. Here were the details, (1) boost-injecting CII-CFA inflamed the mice’hind paws induced the gathering of neutrophiles; (2) Aβ protein deposit, denser and thicker nerve fibers, hypoxia inducible factor-1 (HIF-1) and induced nitric oxide synthase(iNOS) were highly expressed in models’brain, indicating that the AD model were successfully created; (3) after 1 week of EA stimulation, the expression of A β, P-tau, pro-inflammation factors TNF-α and IL-8, HIF-1, oxidative product nitrotyrosine (NT) and the hallmark of microglia IBA-1 were up-regulated, whereas the expression of supp-inflammation factor IL-10, dopamine, anti-oxidative factors melatonin (MT) and catalase (CAT), memory related neurotransmitters like acetyl choline (ACh) and choline acetyl transferase (ChAT) were down-regulated, indicating that EA promoted the neurodegeneration in this phase; (4) after 2 weeks of EA stimulation, the amounts of inflammation factors, dopamine, microglia, hypoxia factors, oxidative products, anti-xoidative products and neurotransmitters were totally the opposite trend from the 1 week situation, indicating that the accumulation of stimulation determined the curing achievements of EA. (5) after operating EA, COX4-one compose of the mitochondria respiratory chain, SIRT1-the activation protein of AMPK pathway, LC3-the hallmark of autophagy, Beclinl-the autophagosome marker, those proteins were continually increased, whereas the expression of deubiquitination enzyme UCHL1 was totally the same trend as that of TNF-α, indicating that the wound-healing effect of EA resulted in the multiplication of mitochondria and the activation of autophagy as well as ubiquitination pathway.ConclusionOur studies have validated that inflammation evokes NO-driven hypoxia and oxidative stress lesions that results in AD.