Our researchers can use this whenever they come up with methods to make neuroplasticity and neurogenesis repeatable on demand.
Construction of biomimetic nanomedicine delivery system based on biomedical materials for treating brain diseases: A review
Introduction
As the trend of population aging continues to intensify, the incidence of brain diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), cerebral stroke (CVA), encephalitis, and brain tumors have been steadily increasing year by year, making them one of the most significant threats to human health today. Currently, the most effective treatment plan for brain diseases remains chemical drug therapy. However, due to the blood-brain barrier (BBB), it is incredibly challenging to achieve effective drug delivery to the brain via non-invasive methods from peripheral blood. As a semi-permeable membrane biological barrier [1], the BBB blocks almost all macromolecular drugs and 98% of small molecule drugs from entering the brain parenchyma, which makes the drug molecules for treating brain diseases have a low penetration rate through the BBB, seriously hindering the non-invasive drug treatment of the disease [2].
With the development of nanotechnology, the design of nanomedicine delivery systems has emerged as an effective strategy for transporting drugs to diseased areas. An increasing number of delivery carriers, such as polymer carriers, nanogels, liposomes, biological carriers, and inorganic nanomaterials, are being used in nanomedicine delivery. These carriers often play a role in protecting and increasing the drug loading capacity, and can also reduce drug degradation and clearance. However, researchers have also found that, regardless of whether these nano-like particles cross the BBB through passive diffusion or active transport, the overall effect is minimal. Nanoparticles that adopt passive diffusion usually accumulate and release drugs at the pathological site by enhancing permeability and the retention effect (EPR) [3]. However, the passive delivery method is prone to off-target effects, resulting in toxic side effects caused by drug accumulation in other organs and tissues in the body. Additionally, these nanoparticles in the blood are readily cleared by phagocytic cells, resulting in a relatively small amount of drug reaching the target site [4]. Moreover, the active delivery method locates and binds to diseased cells or their surrounding microenvironment via specific ligand functionalization or self-targeting carriers (Fig. 1). However, issues regarding the safety, stability, and biocompatibility of the functionalized nanomedicine delivery systems remain limiting factors for effective drug delivery. They may even trigger unnecessary immune responses [5]. Therefore, to achieve drug delivery for brain diseases, more advanced drug delivery systems need to be developed.
The biomimetic nanomedicine delivery system has attracted increasing attention in recent years due to its excellent biocompatibility and its inherent multi-functional integration capability. This type of system can simulate the structure or function of living organisms and has strategies for delivering drugs used to treat brain diseases. They are mainly divided into two types: one is a design scheme based on artificially synthesized biomimetic materials with functions, such as hydrogels with excellent mechanical strength. The other is a design scheme based on natural biomaterials, such as immune cells loaded with nanomedicines and transported via chemical or biological binding. A biomimetic nanomedicine delivery system based on biomaterials is one created from the structure and function of natural biological organisms. These biomimetic carriers can retain or mimic the natural characteristics of cells, viruses, and endogenous substances [6]. Compared to other nanomedicine delivery systems, biomaterials can endow nanomedicines with unique biological activity, thereby improving biocompatibility and reducing immunogenicity. These endogenous carriers are not readily cleared by the body's endothelial reticular network, allowing nanoparticles to circulate for extended periods and exhibit good in vivo degradability. Many biomimetic carriers based on biomaterials have natural targeting properties for the target without modification, for example, immune cells themselves can cross the BBB and tend to the brain inflammation and tumor areas (Scheme 1). Compared with drug delivery systems based on other materials, the biomimetic nanomedicine delivery system based on biological materials not only serves as a drug-loading platform for the target site, but also retains the inherent active components and characteristics of the biological source, resulting in lower in vivo toxicity. It can carry therapeutic drugs across the BBB (Scheme 2) and adopt a synergistic method to treat brain diseases [7]. For example, researchers can adopt Trojan horse [8], hitchhiking [9], and backpack strategies [10] based on cells and their derivatives to expand the drug loading capacity and the surface modifiable area, creating a vast design space for surface modification, functionalization modification, regulation of biological activity, extension of in vivo circulation time, and improvement of biocompatibility. This article, based on different biomimetic carriers as the framework, systematically discusses the latest research progress of delivery systems using cell membranes, living cells, bacteria, exosomes, viruses, albumin, and lipoprotein carriers for treating brain diseases. Starting from the design ideas of drug loading and delivery systems, it critically discusses the advantages and disadvantages of these biomimetic carriers in constructing delivery systems. The innovation and replicability of these brain-targeted delivery and disease visualization strategies are summarized. By integrating insights from materials science and clinical medicine, this review aims to guide the research and development of biomimetic nanomedicine delivery systems based on biological materials for treating brain diseases.
No comments:
Post a Comment