miR-129 Regulates Cell Viability in Alzheimer’s Disease Through Targeting Amyloid Precursor Protein (APP)

2022 ◽  
Vol 12 (4) ◽  
pp. 867-872
Qunwei You ◽  
Wenjie Wang ◽  
Taotao Tao ◽  
Tianyu Wang ◽  
Danhong Zhang ◽  

This study intends to explore miR-129’s effect on cell viability of Alzheimer’s disease by regulating the target gene APP. The hippocampal neurons were assigned into model group (MO group); mimetic group (SI group); inhibitor group (IN group) followed by analysis of hippocampal neuronal cell proliferation and activity, APP protein content, miR-129 expression and cell apoptosis by CCK-8 assay, Western blot method, MTT assay, qRT-PCR and flow cytometry. miR-129 expression of hippocampal neurons in IN group was lowest. Compared with IN and MO groups, SI group had significantly increased miR-129 level and reduced number of hippocampal neuron apoptosis (P < 0.05). Compared with IN group, MO group had significantly reduced cell apoptosis (P < 0.05). SI group had highest number of hippocampal neurons proliferation followed by IN group. SI group had highest OD value followed by MO group and IN group. The cell activity of SI group was higher than that of IN group and MO group (both P < 0.05). Compared with SI group, rat neuron activity in MO group was significantly higher than IN group (P < 0.05). The APP protein expression of hippocampal neuron cells in SI group was lowest followed by MO group and IN group (P < 0.05). In conclusion, the low miR-129 expression can inhibit the activity of hippocampal neurons possibly through up-regulation of APP protein content.

2020 ◽  
Vol 26 ◽  
Nimra Javaid ◽  
Muhammad Ajmal Shah ◽  
Azhar Rasul ◽  
Zunera Chauhdary ◽  
Uzma Saleem ◽  

: Neurodegeneration is a multifactorial process involved the different cytotoxic pathways that lead towards neuronal cell death. Alzheimer’s disease (AD) is a persistent neurodegenerative disorder that normally has a steady onset yet later on it worsens. The documented evidence of AD neuropathology manifested the neuro-inflammation, increased reactive oxygen, nitrogen species and decreased antioxidant protective process; mitochondrial dysfunction as well as increased level of acetylcholinesterase activity. Moreover, enhanced action of proteins leads towards neural apoptosis which have a vital role in the degeneration of neurons. The inability of commercial therapeutic options to treat AD with targeting single mechanism leads the attraction towards organic drugs. Ellagic acid is a dimer of gallic acid, latest studies expressed that ellagic acid can initiate the numerous cell signaling transmission and decrease the progression of disorders, involved in the degeneration of neurons. The influential property of ellagic acid to protect the neurons in neurodegenerative disorders is due to its antioxidant effect, iron chelating and mitochondrial protective effect. The main goal of this review is to critically analyze the molecular mode of action of ellagic acid against neurodegeneration.

2020 ◽  
Vol 20 (26) ◽  
pp. 2380-2390 ◽  
Md. Sahab Uddin ◽  
Abdullah Al Mamun ◽  
Md. Ataur Rahman ◽  
Tapan Behl ◽  
Asma Perveen ◽  

Objective: Alzheimer's disease (AD) is a devastating neurodegenerative disorder, characterized by the extracellular accumulations of amyloid beta (Aβ) as senile plaques and intracellular aggregations of tau in the form of neurofibrillary tangles (NFTs) in specific brain regions. In this review, we focus on the interaction of Aβ and tau with cytosolic proteins and several cell organelles as well as associated neurotoxicity in AD. Summary: Misfolded proteins present in cells accompanied by correctly folded, intermediately folded, as well as unfolded species. Misfolded proteins can be degraded or refolded properly with the aid of chaperone proteins, which are playing a pivotal role in protein folding, trafficking as well as intermediate stabilization in healthy cells. The continuous aggregation of misfolded proteins in the absence of their proper clearance could result in amyloid disease including AD. The neuropathological changes of AD brain include the atypical cellular accumulation of misfolded proteins as well as the loss of neurons and synapses in the cerebral cortex and certain subcortical regions. The mechanism of neurodegeneration in AD that leads to severe neuronal cell death and memory dysfunctions is not completely understood until now. Conclusion: Examining the impact, as well as the consequences of protein misfolding, could help to uncover the molecular etiologies behind the complicated AD pathogenesis.

2021 ◽  
pp. 1-20
Yang Yu ◽  
Yang Gao ◽  
Bengt Winblad ◽  
Lars Tjernberg ◽  
Sophia Schedin Weiss

Background: Processing of the amyloid-β protein precursor (AβPP) is neurophysiologically important due to the resulting fragments that regulate synapse biology, as well as potentially harmful due to generation of the 42 amino acid long amyloid β-peptide (Aβ 42), which is a key player in Alzheimer’s disease. Objective: Our aim was to clarify the subcellular locations of the amyloidogenic AβPP processing in primary neurons, including the intracellular pools of the immediate substrate, AβPP C-terminal fragment (APP-CTF) and the product (Aβ 42). To overcome the difficulties of resolving these compartments due to their small size, we used super-resolution microscopy. Methods: Mouse primary hippocampal neurons were immunolabelled and imaged by stimulated emission depletion (STED) microscopy, including three-dimensional, three-channel imaging and image analyses. Results: The first (β-secretase) and second (γ-secretase) cleavages of AβPP were localized to functionally and distally distinct compartments. The β-secretase cleavage was observed in early endosomes, where we were able to show that the liberated N- and C-terminal fragments were sorted into distinct vesicles budding from the early endosomes in soma. Lack of colocalization of Aβ 42 and APP-CTF in soma suggested that γ-secretase cleavage occurs in neurites. Indeed, APP-CTF was, in line with Aβ 42 in our previous study, enriched in the presynapse but absent from the postsynapse. In contrast, full-length AβPP was not detected in either the pre- or the postsynaptic side of the synapse. Furthermore, we observed that endogenously produced and endocytosed Aβ 42 were localized in different compartments. Conclusion: These findings provide critical super-resolved insight into amyloidogenic AβPP processing in primary neurons.

Sign in / Sign up

Export Citation Format

Share Document