Structural biology of cell surface receptors implicated in Alzheimer’s disease

Alzheimer's disease: The role of proteins in formation, mechanisms, and new therapeutic approaches

Alzheimer's disease (AD) is a progressive neurological disorder that affects the central nervous system (CNS), leading to memory and cognitive decline. In AD, the brain experiences three main structural changes: a significant decrease in the quantity of neurons, the development of neurofibrillary tangles (NFT) composed of hyperphosphorylated tau protein, and the formation of amyloid beta (Aβ) or senile plaques, which are protein deposits found outside cells and surrounded by dystrophic neurites. Genetic studies have identified four genes associated with autosomal dominant or familial early-onset AD (FAD): amyloid precursor protein (APP), presenilin 1 (PS1), presenilin 2 (PS2), and apolipoprotein E (ApoE). The formation of plaques primarily involves the accumulation of Aβ, which can be influenced by mutations in APP, PS1, PS2, or ApoE genes. Mutations in the APP and presenilin (PS) proteins can cause an increased amyloid β peptides production, especially the further form of amyloidogenic known as Aβ42. Apart from genetic factors, environmental factors such as cytokines and neurotoxins may also have a significant impact on the development and progression of AD by influencing the formation of amyloid plaques and intracellular tangles. Exploring the causes and implications of protein aggregation in the brain could lead to innovative therapeutic approaches. Some promising therapy strategies that have reached the clinical stage include using acetylcholinesterase inhibitors, estrogen, nonsteroidal anti-inflammatory drugs (NSAIDs), antioxidants, and antiapoptotic agents. The most hopeful therapeutic strategies involve inhibiting activity of secretase and preventing the β-amyloid oligomers and fibrils formation, which are associated with the β-amyloid fibrils accumulation in AD. Additionally, immunotherapy development holds promise as a progressive therapeutic approach for treatment of AD. Recently, the two primary categories of brain stimulation techniques that have been studied for the treatment of AD are invasive brain stimulation (IBS) and non-invasive brain stimulation (NIBS). In this article, the amyloid proteins that play a significant role in the AD formation, the mechanism of disease formation as well as new drugs utilized to treat of AD will be reviewed.

Bisdemethoxycurcumin (BDC)-Loaded H-Ferritin-Nanocages Mediate the Regulation of Inflammation in Alzheimer's Disease Patients

BACKGROUND

Bisdemethoxycurcumin (BDC) might be an inflammation inhibitor in Alzheimer's Disease (AD). However, BDC is almost insoluble in water, poorly absorbed by the organism, and degrades rapidly. We thus developed a new nanoformulation of BDC based on H-Ferritin nanocages (BDC-HFn).

METHODS

We tested the BDC-HFn solubility, stability, and ability to cross a blood-brain barrier (BBB) model. We tested the effect of BDC-HFn on AD and control (CTR) PBMCs to evaluate the transcriptomic profile by RNA-seq.

RESULTS

We developed a nanoformulation with a diameter of 12 nm to improve the solubility and stability. The comparison of the transcriptomics analyses between AD patients before and after BDC-HFn treatment showed a major number of DEG (2517). The pathway analysis showed that chemokines and macrophages activation differed between AD patients and controls after BDC-HFn treatment. BDC-HFn binds endothelial cells from the cerebral cortex and crosses through a BBB in vitro model.

CONCLUSIONS

Our data showed how BDC-Hfn could improve the stability of BDC. Significant differences in genes associated with inflammation between the same patients before and after BDC-Hfn treatment have been found. Inflammatory genes that are upregulated between AD and CTR after BDC-HFn treatment are converted and downregulated, suggesting a possible therapeutic approach.

Design, Synthesis, and Bioactivity of Novel Bifunctional Small Molecules for Alzheimer's disease

The abnormal phosphorylation of the τ-protein is a typical early pathological feature of Alzheimer's disease (AD). The excessive phosphorylation of the τ-protein in the brain causes the formation of neurofibrillary tangles (NFTs) and increases the neurotoxicity of amyloid-β (Aβ). Thus, targeting the τ-protein is considered a promising strategy for treating AD. Herein, we designed and synthesized a series of molecules containing bifunctional groups to recognize the τ-protein and the E3 ligase. The molecules were examined in vitro, and their effects were tested on PC12 cells. In addition, we further studied the pharmacokinetics of compound I3 in healthy rats. Our data showed that compound I3 could effectively degrade τ-protein, reduce Aβ-induced cytotoxicity, and regulate the uneven distribution of mitochondria, which may open a new therapeutic strategy for the treatment of AD.

Biophysical Reviews: from the umbra of 2020-2021 into the antumbra of 2022

This sub-Editorial for Volume 14 Issue 1 (2022) first makes comment on the current issue and then describes matters of interest related to the journal's activities in 2022-chief among which are (i.) the announcement of the winner of the 2022 Michèle Auger Award for Young Scientists' Independent Research, (ii.) an outline of this year's finalized Special Issue (SI) lineup, (iii.) a description of a new production service offered by Springer to those submitting to the Biophysical Reviews journal, and (iv.) an introduction of newly appointed members of the Biophysical Reviews' Editorial Board.