scholarly journals Delivery of BACE1 siRNA mediated by TARBP-BTP fusion protein reduces β-amyloid deposits in a transgenic mouse model of Alzheimer’s Disease

2016 ◽  
Author(s):  
Mohamed M Haroon ◽  
Kamal Saba ◽  
Venkata H Boddeda ◽  
Jerald M Kumar ◽  
Anant Bahadur Patel ◽  
...  

AbstractSystemic delivery of nucleic acids to the central nervous system (CNS) is a major challenge for the development of RNA interference-based therapeutics due to absence of stability, target specificity, non-permeability to the blood-brain barrier (BBB), and mainly due to lack of suitable carriers. Using a designed bi-functional fusion protein TARBP-BTP, very recently we demonstrated knockdown of target genes in the brain of both AβPP-PS1 (Alzheimer’s disease, AD) and wildtype C57BL/6 mice upon systemic delivery of a single dose of siRNA. In this report, we further substantiate this hypothesis through an extended study in AβPP-PS1 mice, which upon treatment with seven doses of β-secretase APP cleaving Enzyme 1 (BACE1) siRNA, led to target-specific effects in the mouse brain. Concomitant gene silencing and consequent reduction in plaque load in the cerebral cortex and hippocampus (>60%) in mice treated with TARBP-BTP:siRNA complex further led to improvement in spatial learning and memory, which was assessed and verified through Morris Water Maze test that revealed significant improvement in cognitive function. Moreover, the treatment did not induce any adverse effects as revealed by the histopathology of different organs. The work validates the efficiency of TARBP-BTP fusion protein as an efficient mediator of RNAi giving considerable scope for future intervention of neurodegenerative disorders of the CNS through the use of short nucleic acids as gene specific inhibitors.

2019 ◽  
Vol 37 (1) ◽  
pp. 64-71
Author(s):  
Jing Jiang ◽  
Gang Liu ◽  
Suhua Shi ◽  
Yujie Li ◽  
Zhigang Li

Objectives: To explore whether combined therapy with donepezil and acupuncture is better than treatment with donepezil or acupuncture individually in a rat model of Alzheimer’s disease. Methods: In this study, we randomly divided 40 7.5-month-old senescence-accelerated mouse prone 8 (SAMP8) male mice into four groups: SAMP8, SAMP8+D, SAMP8+MA and SAMP8+D+MA. An additional 10 7.5-month-old SAMR1 male mice were included as a healthy control group (SAMR1). Mice in the SAMP8+D group were given donepezil at a dose of 0.65 µg/g/day; mice in the SAMP8+MA group underwent manual acupuncture at GV20, GV26 and Yintang for 20 min per day; mice in the SAMP8+D+MA received both donepezil and manual acupuncture; and mice in the SAMR1 and SAMP8 groups underwent restraint only to control for the effects of handling. After the 15-day treatment, the Morris water maze test, micro-PET(positron-emission tomography), H&E (haematoxylin and eosin) staining, and immunohistochemistry were used to study the differences between donepezil (SAMP8+D), acupuncture (SAMP8+MA), and donepezil combined with acupuncture (SAMP8+D+MA) therapy for the treatment of Alzheimer’s disease. Results: We found that, compared with the untreated SAMP8 group, donepezil, manual acupuncture, and combined therapy with donepezil and manual acupuncture all improved spatial learning and memory ability, the level of glucose metabolism in the brain, and the content of Aβ amyloid in the cortex. Moreover, combined therapy outperformed treatment with donepezil or acupuncture individually in the SAMP8 mice. Conclusion: This study shows that the combination of manual acupuncture and donepezil in an Alzheimer’s disease animal model is superior to acupuncture and donezepil alone. However, randomised controlled trials should be undertaken to clarify the clinical efficacy of combination therapy.


2021 ◽  
Vol 152 ◽  
pp. 105292
Author(s):  
Jacob M. Basak ◽  
Aura Ferreiro ◽  
Lucy S. Cohen ◽  
Patrick W. Sheehan ◽  
Collin J. Nadarajah ◽  
...  

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Jing Jiang ◽  
Gang Liu ◽  
Suhua Shi ◽  
Zhigang Li

Objectives. To compare musical electroacupuncture and electroacupuncture in a mouse model of Alzheimer’s disease.Methods. In this study, 7.5-month-old male senescence-accelerated mouse prone 8 (SAMP8) mice were used as an Alzheimer’s disease animal model. In the normal control paradigm, 7.5-month-old male SAMR1 mice were used as the blank control group (N group). After 15 days of treatment, using Morris water maze test, micro-PET, and immunohistochemistry, the differences among the musical electroacupuncture (MEA), electroacupuncture (EA), Alzheimer’s disease (AD), and normal (N) groups were assessed.Results. The Morris water maze test, micro-PET, and immunohistochemistry revealed that MEA and EA therapies could improve spatial learning and memory ability, glucose metabolism level in the brain, and Aβamyloid content in the frontal lobe, compared with the AD group (P<0.05). Moreover, MEA therapy performed better than EA treatment in decreasing amyloid-beta levels in the frontal lobe of mice with AD.Conclusion. MEA therapy may be superior to EA in treating Alzheimer’s disease as demonstrated in SAMP8 mice.


2021 ◽  
Author(s):  
Swati Som ◽  
Justin Antony ◽  
Palanisamy Dhanabal ◽  
Ponnusankar Sivasankaran

Abstract Diosgenin is a neurosteroid derived from the plants and has been previously reported for its numerous health beneficial properties, such as anti-arrhythmic, hypolipidemic, and antiproliferative effects. Although several studies conducted earlier suggested cognition enhancement actions of diosgenin against neurodegenerative disorders, but the molecular mechanisms underlying are not clearly understood. In the present study, we investigated the neuroprotective effect of diosgenin in the wistar rats that received an intracerebroventricular injection of Amyloid-β (1–42) peptides, representing a rodent model of Alzheimer’s disease (AD). Animals were treated with 100 and 200 mg/kg/p.o of diosgenin for 28 days, followed by Amyloid-β (1–42) peptides infusion. Animals were assessed for the spatial learning and memory by using radial arm maze and passive avoidance task. Subsequently, animals were euthanized and brains were collected for biochemical estimations and histopathological studies. Our results revealed that, diosgenin administration dose dependently improved the spatial learning and memory and protected the animals from Amyloid-β (1–42) peptides induced disrupted cognitive functions. Further, biochemical analysis showed that diosgenin successfully attenuated Amyloid-β (1–42) mediated plaque load, oxidative stress, neuroinflammation and elevated acetylcholinesterase activity. In addition, histopathological evaluation also supported neuroprotective effects of diosgenin in hippocampus of rat brain when assessed using hematoxylin-eosin and Cresyl Violet staining. Thus, the aforementioned effects suggested protective action of diosgenin against Aβ (1–42) induced neuronal damage and thereby can serve as a potential therapeutic candidate for AD.


2020 ◽  
Vol 2020 ◽  
pp. 1-17 ◽  
Author(s):  
Yan-Fang Xian ◽  
Chang Qu ◽  
Yue Liu ◽  
Siu-Po Ip ◽  
Qiu-Ju Yuan ◽  
...  

Alzheimer’s disease (AD) is a common neurodegenerative disease characterized by progressive memory loss. Magnolol (MN), the main active ingredient of Magnolia officinalis, possesses anti-AD effects in several experimental models of AD. In this study, we aimed to explore whether MN could ameliorate the cognitive deficits in TgCRND8 transgenic mice and to elucidate its molecular mechanisms. Male TgCRND8 mice were orally administered with MN (20 and 40 mg/kg) daily for 4 consecutive months, followed by assessing the spatial learning and memory functions using the open-field, radial arm maze, and novel object recognition tests. The results demonstrated that MN (20 and 40 mg/kg) could markedly ameliorate the cognitive deficits in TgCRND8 mice. In addition, MN significantly increased the expression of postsynaptic density protein 93 (PSD93), PSD-95, synapsin-1, synaptotagmin-1, synaptophysin (SYN), and interleukin-10 (IL-10), while markedly reduced the protein levels of tumor necrosis factor alpha (TNF-α), IL-6, IL-1β, Aβ40, and Aβ42, and modulated the amyloid precursor protein (APP) processing and phosphorylation. Immunofluorescence showed that MN significantly suppressed the activation of microglia (Iba-1) and astrocytes (GFAP) in the hippocampus and cerebral cortex of TgCRND8 mice. Mechanistic studies revealed that MN could significantly increase the ratios of p-GSK-3β (Ser9)/GSK-3β, p-Akt (Ser473)/Akt, and p-NF-κB p65/NF-κB p65. These findings indicate that MN exerted cognitive deficits improving effects via suppressing neuroinflammation, amyloid pathology, and synaptic dysfunction through regulating the PI3K/Akt/GSK-3β and NF-κB pathways, suggesting that MN is a promising naturally occurring polyphenol worthy of further developing into a therapeutic agent for AD treatment.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Peng Ren ◽  
Jingwei Chen ◽  
Bingxuan Li ◽  
Mengzhou Zhang ◽  
Bei Yang ◽  
...  

Introduction. Alzheimer’s disease (AD), the most common neurodegenerative disorder, is characterized by the accumulation of amyloid-β (Aβ) peptide and hyperphosphorylated tau protein. Accumulating evidence has revealed that the slow progressive deterioration of AD is associated with oxidative stress and chronic inflammation in the brain. Nuclear factor erythroid 2- (NF-E2-) related factor 2 (Nrf2), which acts through the Nrf2/ARE pathway, is a key regulator of the antioxidant and anti-inflammatory response. Although recent data show a link between Nrf2 and AD-related cognitive decline, the mechanism is still unknown. Thus, we explored how Nrf2 protects brain cells against the oxidative stress and inflammation of AD in a mouse model of AD (APP/PS1 transgenic (AT) mice) with genetic removal of Nrf2. Methods. The spatial learning and memory abilities of 12-month-old transgenic mice were evaluated using a Morris water maze test. Hippocampal levels of Nrf2, Aβ, and p-tauS404 and of astrocytes and microglia were determined by immunostaining. Inflammatory cytokines were determined by ELISA and quantitative real-time polymerase chain reaction (qRT-PCR). Oxidative stress was measured by 8-hydroxydeoxyguanosine immunohistochemistry, and the antioxidant response was determined by qRT-PCR. Results. The spatial learning and memory abilities of AT mice were impaired after Nrf2 deletion. Aβ and p-tauS404 accumulation was increased in the hippocampus of AT/Nrf2-KO mice. Astroglial and microglial activation was exacerbated, followed by upregulation of the proinflammatory cytokines IL-1β, IL-6, and TNF-α. Conclusion. Our present results show that Nrf2 deficiency aggravates AD-like pathology in AT mice. This phenotype was associated with increased levels of oxidative and proinflammatory markers, which suggests that the Nrf2 pathway may be a promising therapeutic target for AD.


2004 ◽  
Vol 164 (4) ◽  
pp. 1495-1502 ◽  
Author(s):  
Christoph Schmitz ◽  
Bart P.F. Rutten ◽  
Andrea Pielen ◽  
Stephanie Schäfer ◽  
Oliver Wirths ◽  
...  

2018 ◽  
Author(s):  
Keiko Ishida ◽  
Masaki Yamamoto ◽  
Koichi Misawa ◽  
Noriyasu Ota ◽  
Akira Shimotoyodome

AbstractEpidemiological studies have found that habitual coffee consumption may reduce the risk of Alzheimer’s disease. Coffee contains numerous phenolic compounds (coffee polyphenols) such as chlorogenic acids. However, evidence demonstrating the contribution of chlorogenic acids in preventing cognitive dysfunction induced by Alzheimer’s disease is limited. In this study, we investigated the effect of chlorogenic acids on prevention of cognitive dysfunction in APP/PS2 transgenic mouse model of Alzheimer’s disease. Five-week-old APP/PS2 mice were administered a diet supplemented with coffee polyphenols daily for 5 months. The memory and cognitive function of mice was determined using the novel object recognition test, the Morris water maze test, and the step-through passive avoidance test. We found that chronic treatment with coffee polyphenols prevented cognitive dysfunction and significantly reduced hippocampal Aβ deposition. We then determined the effect of 5-caffeoylquinic acid, one of the primary components of coffee polyphenols, on Aβ formation. 5-Caffeoylquinic acid did not inhibit Aβ fibrillation, but degraded Aβ fibrils in a dose-dependent manner. In conclusion, these results demonstrate that coffee polyphenols prevented cognitive deficits and alleviated Aβ plaque deposition via disaggregation of Aβ in APP/PS2 mouse.


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