Update on new trends and progress of natural active ingredients in the intervention of Alzheimer's disease, based on understanding of traditional Chinese and Western relevant theories: A review

Gadolinium-Based Magnetic Resonance Theranostic Agent with Gallic Acid as an Anti-Neuroinflammatory and Antioxidant Agent

Studies in the field have actively pursued the incorporation of diverse biological functionalities into gadolinium-based contrast agents, aiming at the amalgamation of MRI imaging and therapeutic capabilities. In this research, we present the development of Gd-Ga, an anti-neuroinflammatory MR contrast agent strategically designed to target inflammatory mediators for comprehensive imaging diagnosis and targeted lesion treatment. Gd-Ga is a gadolinium complex composed of 1,4,7-tris(carboxymethylaza)cyclododecane-10-azaacetylamide (DO3A) conjugated with gallic acid (3,4,5-trihydroxybenzoic acid). Upon intravenous administration in LPS-induced mouse models, Gd-Ga demonstrated a remarkable three-fold increase in signal-to-noise (SNR) variation compared to Gd-DOTA, particularly evident in both the cortex and hippocampus 30 min post-MR monitoring. In-depth investigations, both in vitro and in vivo, into the anti-neuroinflammatory properties of Gd-Ga revealed significantly reduced protein expression levels of pro-inflammatory mediators compared to the LPS group. The alignment between in silico predictions and phantom studies indicates that Gd-Ga acts as an anti-neuroinflammatory agent by directly binding to MD2. Additionally, the robust antioxidant activity of Gd-Ga was confirmed by its effective scavenging of NO and ROS. Our collective findings emphasize the immense potential of this theranostic complex, where a polyphenol serves as an anti-inflammatory drug, presenting an exceptionally efficient platform for the diagnosis and treatment of neuroinflammation.

Unveiling the Molecular Interactions Between Human Transferrin and Limonene: Natural Compounds in Alzheimer's Disease Therapeutics

Background

Neurodegeneration is a term describing an irreversible process of neuronal damage. In recent decades, research efforts have been directed towards deepening our knowledge of numerous neurodegenerative disorders, with a particular focus on conditions such as Alzheimer's disease (AD). Human transferrin (htf) is a key player in maintaining iron homeostasis within brain cells. Any disturbance in this equilibrium gives rise to the emergence of neurodegenerative diseases and associated pathologies, particularly AD. Limonene, a natural compound found in citrus fruits and various plants, has shown potential neuroprotective properties.

Objective

In this study, our goal was to unravel the binding of limonene with htf, with the intention of comprehending the interaction mechanism of limonene with htf.

Methods

Binding was scrutinized using fluorescence quenching and UV-Vis spectroscopic analyses. The binding mechanism of limonene was further investigated at the atomic level through molecular docking and extensive 200 ns molecular dynamic simulation (MD) studies.

Results

Molecular docking uncovered that limonene interacted extensively with the deep cavity located within the htf binding pocket. MD results indicated that binding of limonene to htf did not induce substantial structural alterations, ultimately forming stable complex. The findings from fluorescence binding indicated a pronounced interaction between limonene and htf, limonene binds to htf with a binding constant (K) of 0.1×105 M-1. UV spectroscopy also advocated stable htf-limonene complex formation.

Conclusions

The study deciphered the binding mechanism of limonene with htf, providing a platform to use limonene in AD therapeutics in context of iron homeostasis.