Nanoformulated alpha-mangostin ameliorates Alzheimer's disease neuropathology by elevating LDLR expression and accelerating amyloid-beta clearance

The α-MG exhibits neuroprotective potential by reducing amyloid beta peptide-induced inflammation, oxidative stress, and tau aggregation in human neural stem cells

Alzheimer's disease (AD) is the primary cause of dementia in older adults. Amyloid-beta (Aβ) and tau protein neurofibrillary tangles accumulate in the brain, leading to a progressive decline in memory, thinking, and behavior. Neuroinflammation and oxidative stress play a significant role in the development and progression of AD. Research has suggested that α-mangostin (α-MG), a compound found in mangosteen peels, may have anti-inflammatory, antioxidant, and neuroprotective properties, which could be beneficial in the context of AD. Further research is required to fully comprehend the therapeutic mechanisms of α-MG on AD and determine its potential as a treatment option. α-MG treatment significantly improves the viability of hNSCs exposed to Aβ and reduces caspase activity. Furthermore, this treatment is associated with a notable decrease in the expression of TNF-α and IL-1β. The treatment effectively restores alterations in the expression of IKK and NF-κB (p65) induced by Aβ, which are critical factors in the inflammatory response. Moreover, α-MG effectively reduces iNOS and COX-2 levels in Aβ-treated hNSCs, showcasing its potential therapeutic benefits. Treatment with α-MG protects hNSCs against Aβ-induced oxidative stress and effectively prevents the decrease in Nrf2 levels caused by Aβ. The treatment significantly enhances the activity and mRNA expression of Nrf2 downstream antioxidant target genes, including SOD-1, SOD-2, Gpx1, GSH, catalase, and HO-1, compared to Aβ-treated controls. α-MG significantly reduces tau and ubiquitin (Ub) aggregates, enhances proteasome activity, and increases the mRNA expression of HSF1, HSP27, HSP70, and HSP90 in Tau-GFP-expressed hNSCs. This study significantly improves our comprehension of the anti-inflammatory, antioxidative stress, and anti-aggregated effects of α-MG. These findings have potential therapeutic implications for developing treatments that could delay AD progression and promote healthy aging.

Senescence accelerated mouse-prone 8: a model of neuroinflammation and aging with features of sporadic Alzheimer's disease

The large majority of Alzheimer's disease (AD) cases are sporadic with unknown genetic causes. In contrast, only a small percentage of AD cases are familial, with known genetic causes. Paradoxically, there are only few validated mouse models of sporadic AD but many of familial AD. Senescence accelerated mouse-prone 8 (SAMP8) mice are a model of accelerated aging with features of sporadic AD. They exhibit a more complete suite of human AD-relevant pathologies than most familial models. SAMP8 brains are characterized by inflammation, glial activation, b-amyloid deposits, and hyperphosphorylated Tau. The excess amyloid deposits congregate around blood vessels leading to vascular impairment and leaky BBBs in these mice. SAMP8 mice also exhibit neuronal cell death, a feature not typically seen in models of familial AD. Additionally, adult hippocampal neurogenesis is decreased in SAMP8 mice and correspondingly, they have reduced cognitive ability. In line with this, hippocampal LTP is significantly compromised in SAMP8 mice. No model is perfect and SAMP8 mice are limited by the lack of clarity about their genomic differences from control Senescence Accelerated Mouse-Resistant 1 (SAMR1) mice although their transcriptomics changes are being revealed. To further complicate matters, multiple substrains of SAMP8 mice have emerged over the years, sometimes making comparisons of studies difficult. Despite these challenges, we argue that SAMP8 mice can be useful for studying AD-relevant symptoms and propose important experiments to strengthen this already useful model.

Nanoscale drug formulations for the treatment of Alzheimer's disease progression

Alzheimer's disease (AD) is a devastating neurodegenerative disorder with no effective disease-modifying treatments. The blood-brain barrier hinders drug delivery to the brain, limiting therapeutic efficacy. Nanoparticle-based systems have emerged as promising tools to overcome these challenges. This review highlights recent advances in nanoparticle technologies for AD treatment, including liposomes, polymeric, inorganic, and biomimetic nanoparticles. These nanoparticles improve drug delivery across the blood-brain barrier, improve stability and bioavailability, and enable targeted delivery to affected brain regions. Functionalization strategies further enhance their therapeutic potential. Multifunctional nanoparticles combining therapeutic and diagnostic properties offer theranostic approaches. While progress has been made, challenges related to safety, targeting precision, and clinical translation remain. Future perspectives emphasize the need for collaborative efforts to optimize nanoparticle design, conduct rigorous studies, and accelerate the development of effective nanotherapeutics. With continued innovation, nanoparticle-based delivery systems hold great promise for revolutionizing AD treatment.

Progress in the treatment of Alzheimer's disease based on nanosized traditional Chinese medicines

Traditional Chinese medicine (TCM) has been employed for centuries in treating and managing Alzheimer's disease (AD). However, their effective delivery to target sites can be a major challenge. This is due to their poor water solubility, low bioavailability, and potential toxicity. Furthermore, the blood-brain barrier (BBB) is a major obstacle to effective TCM delivery, significantly reducing efficacy. Advancements in nanotechnology and its applications in TCM (nano-TCM) can deliver active ingredients or components of TCM across the BBB to the targeted brain area. This review summarizes the recent advances in nanocarrier-based delivery systems for different types of active constituents of TCM for AD, including terpenoids, polyphenols, alkaloids, flavonoids, and quinones. Besides, the main challenges and opportunities for the future development of these advanced TCM nanocarriers are emphasized. In conclusion, this review provides valuable insights and guidance for utilizing nanocarriers to shape future TCM drug delivery.

Recent Progress in Nanomedicine for the Diagnosis and Treatment of Alzheimer's Diseases

Alzheimer's disease (AD) is a neurodegenerative disease that causes memory loss and progressive and permanent deterioration of cognitive function. The most challenging issue in combating AD is its complicated pathogenesis, which includes the deposition of amyloid β (Aβ) plaques, intracellular hyperphosphorylated tau protein, neurofibrillary tangles (NFT), etc. Despite rapid advancements in mechanistic research and drug development for AD, the currently developed drugs only improve cognitive ability and temporarily relieve symptoms but cannot prevent the development of AD. Moreover, the blood-brain barrier (BBB) creates a huge barrier to drug delivery in the brain. Therefore, effective diagnostic tools and treatments are urgently needed. In recent years, nanomedicine has provided opportunities to overcome the challenges and limitations associated with traditional diagnostics or treatments. Various types of nanoparticles (NPs) play an essential role in nanomedicine for the diagnosis and treatment of AD, acting as drug carriers to improve targeting and bioavailability across/bypass the BBB or acting as drugs directly on AD lesions. This review categorizes different types of NPs and summarizes their applications in nanomedicine for the diagnosis and treatment of AD. It also discusses the challenges associated with clinical applications and explores the latest developments and prospects of nanomedicine for AD.

Polymer nanotherapeutics: A promising approach toward microglial inhibition in neurodegenerative diseases

Nanoparticles (NPs) that target multiple transport mechanisms facilitate targeted delivery of active therapeutic agents to the central nervous system (CNS) and improve therapeutic transport and efficacy across the blood-brain barrier (BBB). CNS nanotherapeutics mostly target neurons and endothelial cells, however, microglial immune cells are the first line of defense against neuronal damage and brain infections. Through triggering release of inflammatory cytokines, chemokines and proteases, microglia can however precipitate neurological damage-a significant factor in neurodegenerative diseases. Thus, microglial inhibitory agents are attracting much attention among those researching and developing novel treatments for neurodegenerative disorders. The most established inhibitors of microglia investigated to date are resveratrol, curcumin, quercetin, and minocycline. Thus, there is great interest in developing novel agents that can bypass or easily cross the BBB. One such approach is the use of modified-nanocarriers as, or for, delivery of, therapeutic agents to the brain and wider CNS. For microglial inhibition, polymeric NPs are the preferred vehicles for choice. Here, we summarize the immunologic and neuroinflammatory role of microglia, established microglia inhibitor agents, challenges of CNS drug delivery, and the nanotherapeutics explored for microglia inhibition to date. We also discuss applications of the currently considered "most useful" polymeric NPs for microglial-inhibitor drug delivery in CNS-related diseases.

Olive Oil Industry By-Products as a Novel Source of Biophenols with a Promising Role in Alzheimer Disease Prevention

This review explores the potential health benefits and applications of phenolic secoiridoids derived from olive oil by-products in the prevention of Alzheimer's disease (AD). As reviewed herein, polyphenols, such as epigallocatechin-3-gallate, epicatechin, and resveratrol, show in vitro and in vivo antioxidant, anti-inflammatory, and neuroprotective properties, and are particularly relevant in the context of AD, a leading cause of dementia globally. The olive oil industry, particularly in the Mediterranean region, produces significant amounts of waste, including leaves, pomace, and wastewater, which pose environmental challenges but also offer an untapped source of bioactive compounds. Despite promising in vitro and in vivo studies indicating that olive-derived polyphenols, such as oleuropein and hydroxytyrosol, may mitigate AD pathology, human clinical trials remain limited. The variability in extraction methods and the complex nature of AD further complicate research. Future studies should focus on standardizing the protocols and conducting robust clinical trials to fully assess the therapeutic potential of these compounds. This approach not only supports the development of new treatments for AD but also promotes environmental sustainability by valorizing olive oil industry waste.

ROS-responsive biomimetic nanosystem camouflaged by hybrid membranes of platelet-exosomes engineered with neuronal targeting peptide for TBI therapy

Recovery and survival following traumatic brain injury (TBI) depends on optimal amelioration of secondary injuries at lesion site. Delivering mitochondria-protecting drugs to neurons may revive damaged neurons at sites secondarily traumatized by TBI. Pioglitazone (PGZ) is a promising candidate for TBI treatment, limited by its low brain accumulation and poor targetability to neurons. Herein, we report a ROS-responsive nanosystem, camouflaged by hybrid membranes of platelets and engineered extracellular vesicles (EVs) (C3-EPm-|TKNPs|), that can be used for targeted delivery of PGZ for TBI therapy. Inspired by intrinsic ability of macrophages for inflammatory chemotaxis, engineered M2-like macrophage-derived EVs were constructed by fusing C3 peptide to EVs membrane integrator protein, Lamp2b, to confer them with ability to target neurons in inflamed lesions. Platelets provided hybridized EPm with capabilities to target hemorrhagic area caused by trauma via surface proteins. Consequently, C3-EPm-|PGZ-TKNPs| were orientedly delivered to neurons located in the traumatized hemisphere after intravenous administration, and triggered the release of PGZ from TKNPs via oxidative stress. The current work demonstrate that C3-EPm-|TKNPs| can effectively deliver PGZ to alleviate mitochondrial damage via mitoNEET for neuroprotection, further reversing behavioral deficits in TBI mice. Our findings provide proof-of-concept evidence of C3-EPm-|TKNPs|-derived nanodrugs as potential clinical approaches against neuroinflammation-related intracranial diseases.

Intracerebral fate of organic and inorganic nanoparticles is dependent on microglial extracellular vesicle function

Nanoparticles (NPs) represent an important advance for delivering diagnostic and therapeutic agents across the blood-brain barrier. However, NP clearance is critical for safety and therapeutic applicability. Here we report on a study of the clearance of model organic and inorganic NPs from the brain. We find that microglial extracellular vesicles (EVs) play a crucial role in the clearance of inorganic and organic NPs from the brain. Inorganic NPs, unlike organic NPs, perturb the biogenesis of microglial EVs through the inhibition of ERK1/2 signalling. This increases the accumulation of inorganic NPs in microglia, hindering their elimination via the paravascular route. We also demonstrate that stimulating the release of microglial EVs by an ERK1/2 activator increased the paravascular glymphatic pathway-mediated brain clearance of inorganic NPs. These findings highlight the modulatory role of microglial EVs on the distinct patterns of the clearance of organic and inorganic NPs from the brain and provide a strategy for modulating the intracerebral fate of NPs.

Nanotechnology in the diagnostic and therapy for Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder primarily characterized by β-amyloid plaque, intraneuronal tangles, significant neuronal loss and cognitive deficit. Treatment in the early stages of the disease is crucial for preventing or perhaps reversing the neurodegeneration in the AD cases. However, none of the current diagnostic procedures are capable of early diagnosis of AD. Further, the available treatments merely provide symptomatic alleviation in AD and do not address the underlying illness. Therefore, there is no permanent cure for AD currently. Better therapeutic outcomes need the optimum drug concentration in the central nervous system (CNS) by traversing blood-brain-barrier (BBB). Nanotechnology offers enormous promise to transform the treatment and diagnostics of neurodegenerative diseases. Nanotechnology based diagnostic tools, drug delivery systems and theragnostic are capable of highly sensitive molecular detection, effective drug targeting and their combination. Significant work has been done in this area over the last decade and prospective results have been obtained in AD therapy. This review explores the various applications of nanotechnology in addressing the varied facets of AD, ranging from early detection to therapeutic interventions. This review also looks at how nanotechnology can help with the development of disease-modifying medicines, such as the delivery of anti-amyloid, anti-tau, cholinesterase inhibitors, antioxidants and hormonal drugs. In conclusion, this paper discusses the role of nanotechnology in the early detection of AD, effective drug targeting to the CNS and theragnostic applications in the management of AD.

Naturally Occurring Xanthones; Biological Activities, Chemical Profiles and In Silico Drug Discovery

Xanthones are widely distributed polyphenols, present commonly in higher plants; Garcinia, Calophyllum, Hypericum, Platonia, Mangifera, Gentiana and Swertia. Xanthone tricyclic scaffold is able to interact with different biological targets, showing antibacterial and cytotoxic effects, as well as potent effects against osteoarthritis, malaria, and cardiovascular diseases. Thus, in this article we focused on pharmacological effects, applications and preclinical studies with the recent updates of xanthon´s isolated compounds from 2017-2020. We found that only α-mangostin, gambogic acid, and mangiferin, have been subjected to preclinical studies with particular emphasis on the development of anticancer, diabetes, antimicrobial and hepatoprotective therapeutics. Molecular docking calculations were performed to predict the binding affinities of xanthone-derived compounds against SARS-CoV-2 M^pro. According to the results, cratoxanthone E and morellic acid demonstrated promising binding affinities towards SARS-CoV-2 M^pro with docking scores of -11.2 and -11.0 kcal/mol, respectively. Binding features manifested the capability of cratoxanthone E and morellic acid to exhibit nine and five hydrogen bonds, respectively, with the key amino acids of the M^pro active site. In conclusion, cratoxanthone E and morellic acid are promising anti-COVID-19 drug candidates that warrant further detailed in vivo experimental estimation and clinical assessment.

Contextualizing the Role of Osteopontin in the Inflammatory Responses of Alzheimer's Disease

Alzheimer's disease (AD) is characterized by progressive accumulations of extracellular amyloid-beta (Aβ) aggregates from soluble oligomers to insoluble plaques and hyperphosphorylated intraneuronal tau, also from soluble oligomers to insoluble neurofibrillary tangles (NFTs). Tau and Aβ complexes spread from the entorhinal cortex of the brain to interconnected regions, where they bind pattern recognition receptors on microglia and astroglia to trigger inflammation and neurotoxicity that ultimately lead to neurodegeneration and clinical AD. Systemic inflammation is initiated by Aβ's egress into the circulation, which may be secondary to microglial activation and can confer both destructive and reparative actions. Microglial activation pathways and downstream drivers of Aβ/NFT neurotoxicity, including inflammatory regulators, are primary targets for AD therapy. Osteopontin (OPN), an inflammatory cytokine and biomarker of AD, is implicated in Aβ clearance and toxicity, microglial activation, and inflammation, and is considered to be a potential therapeutic target. Here, using the most relevant works from the literature, we review and contextualize the evidence for a central role of OPN and associated inflammation in AD.

Cytotoxicity Enhancement of α-Mangostin with Folate-Conjugated Chitosan Nanoparticles in MCF-7 Breast Cancer Cells

α-mangostin (AM) is a promising natural anticancer agent that can be used in cancer research. However, its effectiveness can be limited by poor solubility and bioavailability. To address this issue, chitosan-based nanoparticles (CSNPs) have been investigated as a potential delivery system to enhance the cytotoxicity to cancer cells and improve selectivity against normal cells. In this study, we developed folate-conjugated chitosan nanoparticles (F-CS-NPs) using a carbodiimide-based conjugation method to attach folate to chitosan (CS), which have different molecular weights. The NPs were crosslinked using tripolyphosphate (TPP) via ionic gelation. To characterize the F-CS-NPs, we utilized various analytical techniques, including transmission electron microscopy (TEM) to evaluate the particle size and morphology, Fourier-transform infrared spectroscopy (FTIR) to confirm the presence of functional groups, and ultraviolet-visible spectroscopy (UV-Vis) to measure the absorption spectrum and confirm the presence of folate. The particle size of AM-F-CS-NPs ranged from 180 nm to 250 nm, with many having favorable charges ranging from +40.33 ± 3.4 to 10.69 ± 1.3 mV. All NPs exhibited the same spherical morphology. The use of F-CS-NPs increased drug release, followed by a sustained release pattern. We evaluated the cytotoxicity of AM, AM-F-CS-HMW, and AM-F-CS-LMW NPs against MCF-7 cells and found IC50 values of 8.47 ± 0.49, 5.3 ± 0.01, and 4.70 ± 0.11 µg/mL, respectively. These results confirm the improved cytotoxicity of AM in MCF-7 cells when delivered via F-CS-NPs. Overall, our in vitro study demonstrated that the properties of F-CS-NPs greatly influence the cytotoxicity of AM in MCF-7 breast cancer cells (significantly different (p < 0.05)). The use of F-CS-NPs as a drug-delivery system for AM may have the potential to develop novel therapies for breast cancer.

Protein corona on brain targeted nanocarriers: Challenges and prospects

Safe and efficient medical therapy for brain diseases is still an unmet clinical need due to various barriers represented by the blood-brain barrier. Well-designed brain targeted nanocarriers are potential solutions for enhanced brain drug delivery; however, the complicated in vivo process attenuates performance of nanocarriers, which severely hampers clinical translation. The formation of protein corona (PC) is inevitable for nanocarriers circulation and transport in biofluids, acting as an important factor to regulate in vivo performance of nanocarriers. In this review, the reported strategies have been retrospected for better understanding current situation in developing brain targeted nanocarriers. The interplay between brain targeted nanocarriers and plasma proteins is emphasized to comprehend how the nanocarriers adsorb proteins by certain synthetic identity, and following regulations on in vivo performance of nanocarriers. More importantly, the mainstream methods to promote efficiency of nanocarriers by regulating PC, defined as in vitro functionalization and in vivo functionalization strategies, are also discussed. Finally, viewpoints about future development of brain targeted nanocarriers according to the understanding on nanocarriers-PC interaction are proposed.

The role of protein corona on nanodrugs for organ-targeting and its prospects of application

Nowadays, nanodrugs become a hotspot in the high-end medical field. They have the ability to deliver drugs to reach their destination more effectively due to their unique properties and flexible functionalization. However, the fate of nanodrugs in vivo is not the same as those presented in vitro, which indeed influenced their therapeutic efficacy in vivo. When entering the biological organism, nanodrugs will first come into contact with biological fluids and then be covered by some biomacromolecules, especially proteins. The proteins adsorbed on the surface of nanodrugs are known as protein corona (PC), which causes the loss of prospective organ-targeting abilities. Fortunately, the reasonable utilization of PC may determine the organ-targeting efficiency of systemically administered nanodrugs based on the diverse expression of receptors on cells in different organs. In addition, the nanodrugs for local administration targeting diverse lesion sites will also form unique PC, which plays an important role in the therapeutic effect of nanodrugs. This article introduced the formation of PC on the surface of nanodrugs and summarized the recent studies about the roles of diversified proteins adsorbed on nanodrugs and relevant protein for organ-targeting receptor through different administration pathways, which may deepen our understanding of the role that PC played on organ-targeting and improve the therapeutic efficacy of nanodrugs to promote their clinical translation.

Tailored Apoptotic Vesicle Delivery Platform for Inflammatory Regulation and Tissue Repair to Ameliorate Ischemic Stroke

Apoptotic vesicles (ApoVs) hold great promise for inflammatory regulation and tissue repair. However, little effort has been dedicated to developing ApoV-based drug delivery platforms, while the insufficient targeting capability of ApoVs also limits their clinical applications. This work presents a platform architecture that integrates apoptosis induction, drug loading, and functionalized proteome regulation, followed by targeting modification, enabling the creation of an apoptotic vesicle delivery system to treat ischemic stroke. Briefly, α-mangostin (α-M) was utilized to induce mesenchymal stem cell (MSC) apoptosis while being loaded onto MSC-derived ApoVs as an anti-oxidant and anti-inflammatory agent for cerebral ischemia/reperfusion injury. Matrix metalloproteinase activatable cell-penetrating peptide (MAP), a microenvironment-responsive targeting peptide, was modified on the surface of ApoVs to obtain the MAP-functionalized α-M-loaded ApoVs. Such engineered ApoVs targeted the injured ischemic brain after systemic injection and achieved an enhanced neuroprotective activity due to the synergistic effect of ApoVs and α-M. The internal protein payloads of ApoVs, upon α-M activation, were found engaged in regulating immunological response, angiogenesis, and cell proliferation, all of which contributed to the therapeutic effects of ApoVs. The findings provide a universal framework for creating ApoV-based therapeutic drug delivery systems for the amelioration of inflammatory diseases and demonstrate the potential of MSC-derived ApoVs to treat neural injury.

Biochemical features and therapeutic potential of α-Mangostin: Mechanism of action, medicinal values, and health benefits

α-Mangostin (α-MG) is a natural xanthone obtained from the pericarps of mangosteen. It exhibits excellent potential, including anti-cancer, neuroprotective, antimicrobial, antioxidant, and anti-inflammatory properties, and induces apoptosis. α-MG controls cell proliferation by modulating signaling molecules, thus implicated in cancer therapy. It possesses incredible pharmacological features and modulates crucial cellular and molecular factors. Due to its lesser water solubility and pitiable target selectivity, α-MG has limited clinical application. As a known antioxidant, α-MG has gained significant attention from the scientific community, increasing interest in extensive technical and biomedical applications. Nanoparticle-based drug delivery systems were designed to improve the pharmacological features and efficiency of α-MG. This review is focused on recent developments on the therapeutic potential of α-MG in managing cancer and neurological diseases, with a special focus on its mechanism of action. In addition, we highlighted biochemical and pharmacological features, metabolism, functions, anti-inflammatory, antioxidant effects and pre-clinical applications of α-MG.

Current trends in natural products for the treatment and management of dementia: Computational to clinical studies

The number of preclinical and clinical studies evaluating natural products-based management of dementia has gradually increased, with an exponential rise in 2020 and 2021. Keeping this in mind, we examined current trends from 2016 to 2021 in order to assess the growth potential of natural products in the treatment of dementia. Publicly available literature was collected from various databases like PubMed and Google Scholar. Oxidative stress-related targets, NF-κB pathway, anti-tau aggregation, anti-AChE, and A-β aggregation were found to be common targets and pathways. A retrospective analysis of 33 antidementia natural compounds identified 125 sustainable resources distributed among 65 families, 39 orders, and 7 classes. We found that families such as Berberidaceae, Zingiberaceae, and Fabaceae, as well as orders such as Lamiales, Sapindales, and Myrtales, appear to be important and should be researched further for antidementia compounds. Moreover, some natural products, such as quercetin, curcumin, icariside II, berberine, and resveratrol, have a wide range of applications. Clinical studies and patents support the importance of dietary supplements and natural products, which we will also discuss. Finally, we conclude with the broad scope, future challenges, and opportunities for field researchers.

Nanopolyphenol rejuvenates microglial surveillance of multiple misfolded proteins through metabolic reprogramming

Microglial surveillance plays an essential role in clearing misfolded proteins such as amyloid-beta, tau, and α-synuclein aggregates in neurodegenerative diseases. However, due to the complex structure and ambiguous pathogenic species of the misfolded proteins, a universal approach to remove the misfolded proteins remains unavailable. Here, we found that a polyphenol, α-mangostin, reprogrammed metabolism in the disease-associated microglia through shifting glycolysis to oxidative phosphorylation, which holistically rejuvenated microglial surveillance capacity to enhance microglial phagocytosis and autophagy-mediated degradation of multiple misfolded proteins. Nanoformulation of α-mangostin efficiently delivered α-mangostin to microglia, relieved the reactive status and rejuvenated the misfolded-proteins clearance capacity of microglia, which thus impressively relieved the neuropathological changes in both Alzheimer's disease and Parkinson's disease model mice. These findings provide direct evidences for the concept of rejuvenating microglial surveillance of multiple misfolded proteins through metabolic reprogramming, and demonstrate nanoformulated α-mangostin as a potential and universal therapy against neurodegenerative diseases.

N-Containing α-Mangostin Analogs via Smiles Rearrangement as the Promising Cytotoxic, Antitrypanosomal, and SARS-CoV-2 Main Protease Inhibitory Agents

New N-containing xanthone analogs of α-mangostin were synthesized via one-pot Smiles rearrangement. Using cesium carbonate in the presence of 2-chloroacetamide and catalytic potassium iodide, α-mangostin (1) was subsequently transformed in three steps to provide ether 2, amide 3, and amine 4 in good yields at an optimum ratio of 1:3:3, respectively. The evaluation of the biological activities of α-mangostin and analogs 2-4 was described. Amine 4 showed promising cytotoxicity against the non-small-cell lung cancer H460 cell line fourfold more potent than that of cisplatin. Both compounds 3 and 4 possessed antitrypanosomal properties against Trypanosoma brucei rhodesiense at a potency threefold stronger than that of α-mangostin. Furthermore, ether 2 gave potent SARS-CoV-2 main protease inhibition by suppressing 3-chymotrypsinlike protease (3CL^pro) activity approximately threefold better than that of 1. Fragment molecular orbital method (FMO-RIMP2/PCM) indicated the improved binding interaction of 2 in the 3CL^pro active site regarding an additional ether moiety. Thus, the series of N-containing α-mangostin analogs prospectively enhance druglike properties based on isosteric replacement and would be further studied as potential biotically active chemical entries, particularly for anti-lung-cancer, antitrypanosomal, and anti-SARS-CoV-2 main protease applications.

Comprehensive analyses of transcriptomes induced by Lyme spirochete infection to CNS model system

BACKGROUND

Lyme disease is a zoonotic disease caused by infection with Borrelia burgdorferi (Bb), the involvement of the nervous system in Lyme disease is usually referred to as Lyme neuroborreliosis (LNB). LNB has diverse clinical manifestations, most commonly including meningitis, Bell's palsy, and encephalitis. However, the molecular pathogenesis of neuroborreliosis is still poorly understood. Comprehensive transcriptomic analysis following Bb infection could provide new insights into the pathogenesis of LNB and may identify novel biomarkers or therapeutic targets for LNB diagnosis and treatment.

METHODS

In the present study, we pooled transcriptomic dataset of Macaca mulatta (rhesus) from our laboratory and the human astrocyte dataset GSE85143 from the Gene Expression Omnibus database to screen common differentially expressed genes (DEGs) in the Bb infection group and the control group. Functional and enrichment analyses were applied for the DEGs. Protein-Protein Interaction network, and hub genes were identified using the Search Tool for the Retrieval of Interaction Genes database and the CytoHubba plugin. Finally, mRNA expression of hub genes was validated in vitro and ex vivo from Bb infected models and normal controls by quantitative reverse transcription PCR (qRT-PCR).

RESULTS

A total of 80 upregulated DEGs and 32 downregulated DEGs were identified. Among them, 11 hub genes were selected. The pathway enrichment analyses on 11 hub genes revealed that the PI3K-Akt signaling pathway was significantly enriched. The mRNA levels of ANGPT1, TLR6, SREBF1, LDLR, TNC, and ITGA2 in U251 cells and/or rhesus brain explants by exposure to Bb were validated by qRT-PCR.

CONCLUSION

Our study suggested that TLR6, ANGPT1, LDLR, SREBF1, TNC, and ITGA may be candidate mammal biomarkers for LNB, and the TLR6/PI3K-Akt signaling pathway may play an important role in LNB pathogenesis.

Cytotoxicity Enhancement in MCF-7 Breast Cancer Cells with Depolymerized Chitosan Delivery of α-Mangostin

The application of α-mangostin (AMG) in breast cancer research has wide intentions. Chitosan-based nanoparticles (CSNPs) have attractive prospects for developing anticancer drugs, especially in their high flexibility for modification to enhance their anticancer action. This research aimed to study the impact of depolymerized chitosan (CS) on the cytotoxicity enhancement of AMG in MCF-7 breast cancer cells. CSNPs effectivity depends on size, shape, crystallinity degree, and charge surface. Modifying CS molecular weight (MW) is expected to influence CSNPs’ characteristics, impacting size, shape, crystallinity degree, and charge surface. CSNPs are developed using the method of ionic gelation with sodium tripolyphosphate (TPP) as a crosslinker and spray pyrolysis procedure. Nanoparticles’ (NPs) sizes vary from 205.3 ± 81 nm to 450.9 ± 235 nm, ZP charges range from +10.56 mV to +51.56 mV, and entrapment efficiency from 85.35% to 90.45%. The morphology of NPs are all the same spherical forms. In vitro release studies confirmed that AMG–Chitosan–High Molecular Weight (AMG–CS–HMW) and AMG–Chitosan–Low Molecular Weight (AMG–CS–LMW) had a sustained-release system profile. MW has a great influence on surface, drug release, and cytotoxicity enhancement of AMG in CSNPs to MCF-7 cancer cells. The preparations AMG–CS–HMW and AMG–CS–LMW NPs considerably enhanced the cytotoxicity of MCF-7 cells with IC₅₀ values of 5.90 ± 0.08 µg/mL and 4.90 ± 0.16 µg/mL, respectively, as compared with the non-nano particle formulation with an IC₅₀ of 8.47 ± 0.29 µg/mL. These findings suggest that CSNPs can enhance the physicochemical characteristics and cytotoxicity of AMG in breast cancer treatment.

Therapeutic nanotechnologies for Alzheimer's disease: a critical analysis of recent trends and findings

Alzheimer's Disease (AD) is an irreversible neurodegenerative disease for which no disease modifying therapies are presently available. Besides the identification of pathological targets, AD presents numerous clinical and pharmacological challenges such as efficient active delivery to the central nervous system, cell targeting, and long-term dosing. Nanoparticles have been explored to overcome some of these challenges as drug delivery vehicles or drugs themselves. However, early promises have failed to materialize as no nanotechnology-based product has been able to reach the market and very few have moved past preclinical stages. In this review, we perform a critical analysis of the past decade's research on nanomedicine-based therapies for AD at the preclinical and clinical stages. The main obstacles to nanotechnology products and the most promising approaches were also identified, including renewed promise with gene editing, gene modulation, and vaccines.

Nanostructure lipid carriers enhance alpha-mangostin neuroprotective efficacy in mice with rotenone-induced neurodegeneration

Neurodegenerative disease, for instance, Parkinson's disease (PD), is associated with substantia nigra dopaminergic neuronal loss with subsequent striatal dopamine reduction, leading to motor deficits. Currently, there is no available effective therapy for PD; thus, novel therapeutic agents such as natural antioxidants with neuroprotective effects are emerging. Alpha-mangostin (αM) is a xanthone derivative compound from mangosteen peel with a cytoprotective effect depicted in neurodegenerative disease models. However, αM has low aqueous solubility and low biodistribution in the brain. Nanostructured lipid carriers (NLC) have been used to encapsulate bioactive compounds delivered to target organs to improve the oral bioavailability and effectiveness. This study aimed to investigate the effect of αM and αM encapsulated in NLC (αM-NLC) in mice with rotenone-induced PD-like neurodegeneration. Forty male ICR mice were divided into normal, PD, PD + αM, and PD + αM-NLC groups. Vehicle, αM (25 mg/kg/48 h), and αM-NLC (25 mg/kg/48 h) were orally administered, along with PD induction by intraperitoneal injection of rotenone (2.5 mg/kg/48 h) for 4 consecutive weeks. Motor abilities were assessed once a week using rotarod and hanging wire tests. Biochemical analysis of brain oxidative status was conducted, and neuronal populations in substantia nigra par compacta (SNc), striatum, and motor cortex were evaluated using Nissl staining. Tyrosine hydroxylase (TH) immunostaining of SNc and striatum was also evaluated. Results showed that rotenone significantly induced motor deficits concurrent with significant SNc, striatum, and motor cortex neuronal reduction and significantly decreased TH intensity in SNc (p < 0.05). The significant reduction of brain superoxide dismutase activity (p < 0.05) was also detected. Administrations of αM and αM-NLC significantly reduced motor deficits, prevented the reduction of TH intensity in SNc and striatum, and prevented the reduction of neurons in SNc (p < 0.05). Only αM-NLC significantly prevented the reduction of neurons in both striatum and motor cortex (p < 0.05). These were found concurrent with significantly reduced malondialdehyde level and increased catalase and superoxide dismutase activities (p < 0.05). Therefore, this study depicted the neuroprotective effect of αM and αM-NLC against rotenone-induced PD-like neurodegeneration in mice. We indicated an involvement of NLC, emphasizing the protective effect of αM against oxidative stress. Moreover, αM-NLC exhibited broad protection against rotenone-induced neurodegeneration that was not limited to nigrostriatal structures and emphasized the benefit of NLC in enhancing αM neuroprotective effects.

Nanoformulated Bumetanide Ameliorates Social Deficiency in BTBR Mice Model of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder with few medication options. Bumetanide, an FDA-approved diuretic, has been proposed as a viable candidate to treat core symptoms of ASD, however, neither the brain region related to its effect nor the cell-specific mechanism(s) is clear. The availability of nanoparticles provides a viable way to identify pharmacological mechanisms for use in ASD. Here, we found that treatment with bumetanide, in a systemic and medial prefrontal cortex (mPFC) region-specific way, attenuated social deficits in BTBR mice. Furthermore, using poly (ethylene glycol)-poly(l-lactide) (PEG-PLA) nanoparticles [NP(bumetanide)], we showed that the administration of NP(bumetanide) in a mPFC region-specific way also alleviated the social deficits of BTBR mice. Mechanistically, the behavioral effect of NP(bumetanide) was dependent on selective microglia-specific targeting in the mPFC. Pharmacological depletion of microglia significantly reduced the effect of nanoencapsulation and depletion of microglia alone did not improve the social deficits in BTBR mice. These findings suggest the potential therapeutic capabilities of nanotechnology for ASD, as well as the relevant link between bumetanide and immune cells.

Multifunctional Anti-Alzheimer’s Disease Effects of Natural Xanthone Derivatives: A Primary Structure-Activity Evaluation

Background: A series of α-Mangostin (α-M) derivatives were designed and synthesized. α-M and four analogues were evaluated for their multifunctional anti-Alzheimer’s disease (anti-AD) effects on fibrillogenesis, microglial uptake, microglial degradation, and anti-neurotoxicity of Aβ, as well as LPS-induced neuroinflammation. The differences in bioactivities were analyzed to understand the structure-activity relationship for further modifications.

Purpose: This study aims to investigate the anti-AD effects of α-M and elucidate its structure-activity relationship by comparing difference between α-M and several analogues.

Methods: Aβ fibrillogenesis was detected by Thioflavin T fluorometric assay. The levels of Aβ_1-42 and inflammatory cytokines were evaluated by enzyme-linked immunosorbent assay. Neuron viability was examined by the CCK-8 assay. The morphology of ZO-1 of bEnd.3 cultured in BV-2-conditioned medium was evaluated by immunofluorescence staining.

Results: Aβ fibrillogenesis was significantly inhibited by co-incubation with α-M, Zcbd-2 or Zcbd-3. α-M, Zcbd-2, Zcbd-3, and Zcbd-4 decreased the levels of Aβ_1-42 and inflammatory cytokines, and promoted Aβ uptake, degradation and anti-inflammation effects inflammation in microglia. α-M and Zcbd-3 protected neuron viability from Aβ-induced neurotoxicity, and preserved tight junction integrity of bEnd.3 against LPS-induced neuroinflammation.

Conclusion: Zcbd-3 acted as α-M almost in all effects. The structure-activity analysis indicated that the 3-methyl-2-butenyl group at C-8 is essential for the bioactivity of α-M, while modifying the double hydroxylation at the C-2 position may improve the multifunctional anti-AD effects.

The effect of drug loading and multiple administration on the protein corona formation and brain delivery property of PEG-PLA nanoparticles

The presence of protein corona on the surface of nanoparticles modulates their physiological interactions such as cellular association and targeting property. It has been shown that α-mangostin (αM)-loaded poly(ethylene glycol)-poly(l-lactide) (PEG-PLA) nanoparticles (NP-αM) specifically increased low density lipoprotein receptor (LDLR) expression in microglia and improved clearance of amyloid beta (Aβ) after multiple administration. However, how do the nanoparticles cross the blood‒brain barrier and access microglia remain unknown. Here, we studied the brain delivery property of PEG-PLA nanoparticles under different conditions, finding that the nanoparticles exhibited higher brain transport efficiency and microglia uptake efficiency after αM loading and multiple administration. To reveal the mechanism, we performed proteomic analysis to characterize the composition of protein corona formed under various conditions, finding that both drug loading and multiple dosing affect the composition of protein corona and subsequently influence the cellular uptake of nanoparticles in b.End3 and BV-2 cells. Complement proteins, immunoglobulins, RAB5A and CD36 were found to be enriched in the corona and associated with the process of nanoparticles uptake. Collectively, we bring a mechanistic understanding about the modulator role of protein corona on targeted drug delivery, and provide theoretical basis for engineering brain or microglia-specific targeted delivery system.

Activation of SIRT-1 Signalling in the Prevention of Bipolar Disorder and Related Neurocomplications: Target Activators and Influences on Neurological Dysfunctions

SIRT-1 (silent mating-type information regulation 2 homolog-1) is a protein found in neuronal nuclei, microglia, and astrocyte cells of the brain. It is sometimes referred to as NAD + -dependent deacetylase (nicotinamide adenine dinucleotide). The activation of sirtuins (SIRT-1-7) has been shown to protect against a wide range of disorders, including neurodegenerative and neuropsychiatric disorders. SIRT-1 has gained considerable interest from these families because of its early link to long-life expansion and calorie restriction involvement. SIRT-1 is necessary for gene silencing, cell cycle regulation, fat and glucose metabolism, oxidative stress, ageing, and memory formation. In this review, we investigate the role of SIRT-1 downregulation in the progression of bipolar disorder (BD) and neurological abnormalities, as well as related neurological alterations such as genetic dysfunction, neurotransmitter imbalance, oxidative stress-induced apoptosis, and mitochondrial dysfunction. BD is a psychiatric disease distinguished by extreme mood fluctuations that range from depressive lows to manic highs. BD is a complicated disorder with numerous clinical signs and neurocomplications that produce significant behavioural problems. SIRT-1 deficiency in the brain has been demonstrated to affect the activity of its transcription factors and molecular changes, including genetic defects. SIRT-1 is now being studied as a potential therapeutic target for a range of brain disorders. A recent study also found that activating SIRT-1 signalling performs a protective effect in avoiding depression and mania-like behaviours. Furthermore, this review investigates the potential mechanisms by which SIRT-1 regulates neuronal transmission and neurogenesis. As a result of our review, we revealed that SIRT-1 activators have neuroprotective potential in BD and related neurological dysfunctions.

Emerging nanoformulation strategies for phytocompounds and applications from drug delivery to phototherapy to imaging

Over thousands of years, natural bioactive compounds derived from plants (bioactive phytocompounds, BPCs) have been used worldwide to address human health issues. Today, they are a significant resource for drug discovery in the development of modern medicines. Although many BPCs have promising biological activities, most of them cannot be effectively utilized in drugs for therapeutic applications because of their inherent limitations of low solubility, structural instability, short half-life, poor bioavailability, and non-specific distribution to organs. Researchers have utilized emerging nanoformulation (NF) technologies to overcome these limitations as they have demonstrated great potential to improve the solubility, stability, and pharmacokinetic and pharmacodynamic characteristics of BPCs. This review exemplifies NF strategies for resolving the issues associated with BPCs and summarizes recent advances in their preclinical and clinical applications for imaging and therapy. This review also highlights how innovative NF technologies play a leading role in next-generation BPC-based drug development for extended therapeutic applications. Finally, this review discusses the opportunities to take BPCs with meaningful clinical impact from bench to bedside and extend the patent life of BPC-based medicines with new formulations or application to new adjacent diseases beyond the primary drug indications.

•

Natural bioactive phytocompounds derived from plants have been used worldwide to address human health issues. However, most of them cannot be effectively utilized in drugs for therapeutic applications because of their inherent limitations.

•

Nanoformulation approach has recently been underlined as an emerging pharmaceutical strategy to overcome the intrinsic drawbacks of bioactive phytocompounds.

•

Various types of nanoformulation and their up-to-date applications for targeted delivery, phototherapy, and imaging are reviewed. Finally, their clinical implications for the repurposing of bioactive phytocompounds are deliberated.

OAB-14 Effectively Ameliorates the Dysfunction of the Endosomal-Autophagic-Lysosomal Pathway in APP/PS1 Transgenic Mice

In Alzheimer's disease (AD), damaged Aβ clearance contributes to elevated levels of Aβ that cause a series of cytotoxic cascade reactions. Thus, targeting Aβ clearance has now been considered a valid therapeutic approach for AD. Cellular uptake and degradation are important mechanisms for Aβ clearance, which are mainly performed by the endosomal-autophagic-lysosomal (EAL) pathway. Our previous study showed that OAB-14, a novel small molecule designed with bexarotene as the lead compound, treatment for 3 months significantly alleviated cognitive disorders and remarkably reduced the deposition of Aβ without affecting its production in APP/PS1 transgenic mice. Here, we further revealed that enhancement of the EAL activity is one of the mechanisms that increases Aβ clearance after OAB-14 administration for 3 months. OAB-14 facilitates receptor-mediated endocytosis and restores autophagy flux via the AMPK/mTOR pathway. Meanwhile, OAB-14 enhances the lysosomal activity, and reduced Aβ accumulation in lysosomes was observed in OAB-14-treated AD mice. These results suggest that OAB-14 may promote Aβ clearance in lysosomes by alleviating the EAL dysfunction in AD mice.

Involvement of Microglia in Neurodegenerative Diseases: Beneficial Effects of Docosahexahenoic Acid (DHA) Supplied by Food or Combined with Nanoparticles

Neurodegenerative diseases represent a major public health issue and require better therapeutic management. The treatments developed mainly target neuronal activity. However, an inflammatory component must be considered, and microglia may constitute an important therapeutic target. Given the difficulty in developing molecules that can cross the blood–brain barrier, the use of food-derived molecules may be an interesting therapeutic avenue. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid (22:6 omega-3), has an inhibitory action on cell death and oxidative stress induced in the microglia. It also acts on the inflammatory activity of microglia. These data obtained in vitro or on animal models are corroborated by clinical trials showing a protective effect of DHA. Whereas DHA crosses the blood–brain barrier, nutritional intake lacks specificity at both the tissue and cellular level. Nanomedicine offers new tools which favor the delivery of DHA at the cerebral level, especially in microglial cells. Because of the biological activities of DHA and the associated nanotargeting techniques, DHA represents a therapeutic molecule of interest for the treatment of neurodegenerative diseases.

Feedback regulation of coronary artery disease susceptibility gene ADTRP and LDL receptors LDLR/CD36/LOX-1 in endothelia cell functions involved in atherosclerosis

A high level of low-density lipoprotein cholesterol (LDL) is one of the most important risk factors for coronary artery disease (CAD), the leading cause of death worldwide. However, a low concentration of LDL may be protective. Genome-wide association studies revealed that variation in ADTRP gene increased the risk of CAD. In this study, we found that a low concentration of oxidized-LDL induced the expression of ADTRP. Further analyses showed that knockdown of the expression of LDL receptor genes LDLR, CD36, or LOX-1 significantly downregulated ADTRP expression, whereas overexpression of LDLR/CD36/LOX-1 markedly increased ADTRP expression through the NF-κB pathway. Like ADTRP, LDLR, CD36 and LOX-1 were all involved in endothelial cell (EC) functions relevant to the initiation of atherosclerosis. Downregulation of LDLR/CD36/LOX-1 promoted monocyte adhesion to ECs and transendothelial migration of monocytes by increasing expression of ICAM-1, VCAM-1, E-selectin and P-selectin, decreased EC proliferation and migration, and increased EC apoptosis, thereby promoting the initiation of atherosclerosis. Opposite effects were observed with the overexpression of ADTRP and LDLR/CD36/LOX-1 in ECs. Interestingly, through the NF-κB and AKT pathways, overexpression of ADTRP significantly upregulated the expression of LDLR, CD36, and LOX-1, and knockdown of ADTRP expression significantly downregulated the expression of LDLR, CD36, and LOX-1. These data suggest that ADTRP and LDL receptors LDLR/CD36/LOX-1 positively regulate each other, and form a positive regulatory loop that regulates endothelial cell functions, thereby providing a potential protective mechanism against atherosclerosis. Our findings provide a new molecular mechanism by which deregulation of ADTRP and LDLR/CD36/LOX-1 promote the development of atherosclerosis and CAD.

Vitamin K2 protects against Aβ42-induced neurotoxicity by activating autophagy and improving mitochondrial function in Drosophila

OBJECTIVE

Alzheimer disease is characterized by progressive decline in cognitive function due to neurodegeneration induced by accumulation of Aβ and hyperphosphorylated tau protein. This study was conducted to explore the protective effect of vitamin K2 against Aβ42-induced neurotoxicity.

METHODS

Alzheimer disease transgenic Drosophila model used in this study was amyloid beta with the arctic mutation expressed in neurons. Alzheimer disease flies were treated with vitamin K2 for 28 days after eclosion. Aβ42 level in brain was detected by ELISA. Autophagy-related genes and NDUFS3, the core subunit of mitochondrial complex I, were examined using real-Time PCR (RT-PCR) and western blot analysis.

RESULTS

Vitamin K2 improved climbing ability (P = 0.0105), prolonged lifespan (P < 0.0001) and decreased Aβ42 levels (P = 0.0267), upregulated the expression of LC3 and Beclin1(P = 0.0012 and P = 0.0175, respectively), increased the conversion of LC3I to LC3II (P = 0.0206) and decreased p62 level (P =0.0115) in Alzheimer disease flies. In addition, vitamin K2 upregulated the expression of NDUFS3 (P = 0.001) and increased ATP production (P = 0.0033) in Alzheimer disease flies.

CONCLUSION

It seems that vitamin K2 protect against Aβ42-induced neurotoxicity by activation of autophagy and rescue mitochondrial dysfunction, which suggests that it may be a potential valuable therapeutic approach for Alzheimer disease.

Potential Role of Nanoparticles in Treating the Accumulation of Amyloid-Beta Peptide in Alzheimer's Patients

The disorder of Alzheimer's is marked by progressive pathophysiological neurodegeneration. The amino acid peptides in the amyloid plaques found in the brains of people with Alzheimer's disease (AD) are known as amyloid-beta (Aβ). Current treatments are not curative, and the effects associated with AD are reduced. Improving treatment results involved the targeting of drugs at optimum therapeutic concentration. Nanotechnology is seen as an unconventional, modern technology that plays a key role in the treatment of Alzheimer's disease. Using nanoparticles, molecular detection, effective drug targeting, and their combination offer high sensitivity. The aim of this review is to shed light on the function and successful role of nanoparticles to resolve Aβ aggregation and thus to help cure Alzheimer's disease. The analysis divides these nanoparticles into three categories: polymer, lipid, and gold nanoparticles. A thorough comparison was then made between the nanoparticles, which are used according to their role, properties, and size in the procedure. The nanoparticles can prevent the accumulation of Aβ during the efficient delivery of the drug to the cells to treat Alzheimer's disease. Furthermore, this comparison demonstrated the ability of these nanoparticles to deal efficiently with Alzheimer's disease. The role of these nanoparticles varied from delivering the drug to brain cells to dealing with the disease-causing peptide.

Inhibition of biofilm formation by alpha-mangostin loaded nanoparticles against Staphylococcus aureus

This study aimed to investigate the antibiofilm activity of alpha-mangostin (AMG) loaded nanoparticles (nanoAMG) against Staphylococcus aureus, including the methicillin-resistant strain MRSA252. The results indicated that treatment with 24 μmol/L nanoAMG inhibited the formation of biofilm biomass by 53-62%, compared to 40-44% for free AMG (p < 0.05). At 48 μmol/L, biofilms in all nanoAMG treated samples were nearly fully disrupted for the two tested strains, MRSA252 and the methicillin-sensitive strain NCTC6571. That concentration resulted in killing of biofilm cells. A lower concentration of 12 µmol/L nanoAMG inhibited initial adherence of the two bacterial strains by > 50%. In contrast, activity of nanoAMG was limited on preformed mature biofilms, which at a concentration of 48 µmol/L were reduced only by 27% and 22% for NCTC6571 and MRSA252, respectively. The effects of AMG or nanoAMG on the expression of biofilm-related genes showed some noticeable differences between the two strains. For instance, the expression level of ebpS was downregulated in MRSA252 and upregulated in NCTC6571 when those strains were treated with either AMG or nanoAMG. In contrast, the expression of fnbB was down regulated in NCTC6571, while it was up-regulated in the MRSA252. The expression of other biofilm-related genes (icaC, clfB and fnbA) was down regulated in both strains. In conclusion, our results suggest that AMG coated nanoparticles had enhanced biological activity as compared to free AMG, indicating that nanoAMG could be a new and promising inhibitor of biofilm formation to tackle S. aureus, including strains that are resistant to multiple antibiotics.

Neuroprotective Effect of α-Mangostin in the Ameliorating Propionic Acid-Induced Experimental Model of Autism in Wistar Rats

Several studies have documented the role of hyper-activation of extracellular signal-regulated kinases (ERK) in Autism pathogenesis. Alpha-mangostin (AMG) is a phytoconstituents with anti-oxidants, anti-inflammatory, and ERK inhibition properties in many diseases. Our research aims to investigate the neuroprotective effect of AMG in the rat model of intracerebroventricular-propionic acid (ICV-PPA) induced autism with a confirmation of its effect on the ERK signaling. Autism was induced in Wistar rats (total 36 rats; 18 male/18 female) by multiple doses of PPA through ICV injection for 11 days. Actophotometer and beam walking tasks were used to evaluate animals' motor abilities, and the Morris water maze task was utilized to confirm the cognition and memory in animals. Long term administration of AMG 100 mg/kg and AMG 200mg/kg continued from day 12 to day 44 of the experiment. Before that, animals were sacrificed, brains isolated, morphological, gross pathological studies were performed, and neurochemical analysis was performed in the brain homogenates. Cellular and molecular markers, including ERK, myelin basic protein, apoptotic markers including caspase-3, Bax, Bcl-2, neuroinflammatory markers, neurotransmitters, and oxidative stress markers, have been tested throughout the brain. Thus, AMG reduces the overactivation of the ERK signaling and also restored autism-like behavioral and neurochemical alterations.

A review on α-mangostin as a potential multi-target-directed ligand for Alzheimer's disease

Alzheimer's disease (AD) is an age-related neurodegenerative disease characterized by progressive memory loss, declining language skills and other cognitive disorders. AD has brought great mental and economic burden to patients, families and society. However due to the complexity of AD's pathology, drugs developed for the treatment of AD often fail in clinical or experimental trials. The main problems of current anti-AD drugs are low efficacy due to mono-target method or side effects, especially high hepatotoxicity. To tackle these two main problems, multi-target-directed ligand (MTDL) based on "one molecule, multiple targets" has been studied. MTDLs can regulate multiple biological targets at the same time, so it has shown higher efficacy, better safety. As a natural active small molecule, α-mangostin (α-M) has shown potential multi-factor anti-AD activities in a series of studies, furthermore it also has a certain hepatoprotective effect. The good availability of α-M also provides support for its application in clinical research. In this work, multiple activities of α-M related to AD therapy were reviewed, which included anti-cholinesterase, anti-amyloid-cascade, anti-inflammation, anti-oxidative stress, low toxicity, hepatoprotective effects and drug formulation. It shows that α-M is a promising candidate for the treatment of AD.

Neuronal mitochondria-targeted therapy for Alzheimer's disease by systemic delivery of resveratrol using dual-modified novel biomimetic nanosystems

Reactive oxygen species (ROS)-induced neuronal mitochondrial dysfunction is a key pathologic factor in sporadic Alzheimer’s disease (AD). Neuronal mitochondria have been proposed to be a promising therapeutic target for AD, especially for the failures of phase III clinical trials on conventional amyloid-β (Aβ) targeted therapy. However, the efficient intravenous delivery of therapeutic agents to neuronal mitochondria in the brain remains a major challenge due to the complicated physiological environment. Recently, biomaterials-based nanomedicine has been widely investigated for the treatment of AD. Herein, we devised a strategy for functional antioxidant delivery to neuronal mitochondria by loading antioxidants into red blood cell (RBC) membrane-coated nanostructured lipid carriers (NLC) bearing rabies virus glycoprotein (RVG29) and triphenylphosphine cation (TPP) molecules attached to the RBC membrane surface (RVG/TPP NPs@RBCm). With the advantage of suitable physicochemical properties of NLC and unique biological functions of the RBC membrane, RVG/TPP NPs@RBCm are stabilized and enabled sustained drug release, providing improved biocompatibility and long-term circulation. Under the synergistic effects of RVG29 and TPP, RVG/TPP NPs@RBCm can not only penetrate the blood–brain barrier (BBB) but also target neuron cells and further localize in the mitochondria. After encapsulating Resveratrol (RSV) as the model antioxidant, the data demonstrated that RVG/TPP-RSV NPs@RBCm can relieve AD symptoms by mitigating Aβ-related mitochondrial oxidative stress both in vitro and in vivo. The memory impairment in APP/PS1 mice is significantly improved following the systemic administration of RVG/TPP-RSV NPs@RBCm. In conclusion, intravenous neuronal mitochondria-targeted dual-modified novel biomimetic nanosystems are a promising therapeutic candidate for ROS-induced mitochondrial dysfunction in AD.

Water-dispersible unadulterated α-mangostin particles for biomedical applications

α-Mangostin, the extract from pericarp of Garcinia mangostana L . or mangosteen fruit, has been applied in various biomedical products because of its minimal skin irritation, and prominent anti-inflammatory, antimicrobial and immune-modulating activities. Owing to its low water solubility, the particle formulations are necessary for the applications of α-mangostin in aqueous media. The particle formulations are usually prepared using surfactants and/or polymers, usually at a larger amount of these auxiliaries than the amount of α-mangostin itself. Here, we show the self-assembly of α-mangostin molecules into water-dispersible particles without a need of any polymers/surfactants. Investigations on chemical structure, crystallinity and thermal properties of the obtained α-mangostin particles, in comparison to the conventional α-mangostin crystalline solid, confirm no formation of the new compound during the particle formation and suggest changes in intermolecular interactions among α-mangostin molecules and significantly more hydroxyl functionality positioned at the particles' surface. The ability of the water suspension of the α-mangostin to inhibit the growth of Propionibacterium acnes, the acne-causing bacteria, is similar to that of the solution of the conventional α-mangostin in 5% dimethyl sulfoxide. Moreover, at 12.7 ppm in an aqueous environment of RAW 264.7 cell culture, α-mangostin suspension exhibits five times higher anti-inflammatory activity than the conventional α-mangostin solution, with the same acceptable cytotoxicity of less than 20% cell death.

Macrophage membrane-coated nanocarriers Co-Modified by RVG29 and TPP improve brain neuronal mitochondria-targeting and therapeutic efficacy in Alzheimer's disease mice

Neuronal mitochondrial dysfunction caused by excessive reactive oxygen species (ROS) is an early event of sporadic Alzheimer's disease (AD), and considered to be a key pathologic factor in the progression of AD. The targeted delivery of the antioxidants to mitochondria of injured neurons in brain is a promising therapeutic strategy for AD. A safe and effective drug delivery system (DDS) which is able to cross the blood-brain barrier (BBB) and target neuronal mitochondria is necessary. Recently, bioactive materials-based DDS has been widely investigated for the treatment of AD. Herein, we developed macrophage (MA) membrane-coated solid lipid nanoparticles (SLNs) by attaching rabies virus glycoprotein (RVG29) and triphenylphosphine cation (TPP) molecules to the surface of MA membrane (RVG/TPP-MASLNs) for functional antioxidant delivery to neuronal mitochondria. According to the results, MA membranes camouflaged the SLNs from being eliminated by RES-rich organs by inheriting the immunological characteristics of macrophages. The unique properties of the DDS after decoration with RVG29 on the surface was demonstrated by the ability to cross the BBB and the selective targeting to neurons. After entering the neurons in CNS, TPP further lead the DDS to mitochondria driven by electric charge. The Genistein (GS)- encapsulated DDS (RVG/TPP-MASLNs-GS) exhibited the most favorable effects on reliveing AD symptoms in vitro and in vivo by the synergies gained from the combination of MA membranes, RVG29 and TPP. These results demonstrated a promising therapeutic candidate for delaying the progression of AD via neuronal mitochondria-targeted delivery by the designed biomimetic nanosystems.

•

MA membranes inherited the immunological properties of macrophages, providing RVG/TPP-MASLNs with enhanced RES evasion.

•

RVG/TPP-MASLNs combined the advantages of RVG29, TPP and MA, greatly improving the efficiency for brain targeting delivery.

•

The biomimetic nanosystems effectively improve the curative effect of genistein on the symptoms of AD mice with biosafety.

The Role of HDL and HDL Mimetic Peptides as Potential Therapeutics for Alzheimer's Disease

The role of high-density lipoproteins (HDL) in the cardiovascular system has been extensively studied and the cardioprotective effects of HDL are well established. As HDL particles are formed both in the systemic circulation and in the central nervous system, the role of HDL and its associated apolipoproteins in the brain has attracted much research interest in recent years. Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder and the leading cause of dementia worldwide, for which there currently exists no approved disease modifying treatment. Multiple lines of evidence, including a number of large-scale human clinical studies, have shown a robust connection between HDL levels and AD. Low levels of HDL are associated with increased risk and severity of AD, whereas high levels of HDL are correlated with superior cognitive function. Although the mechanisms underlying the protective effects of HDL in the brain are not fully understood, many of the functions of HDL, including reverse lipid/cholesterol transport, anti-inflammation/immune modulation, anti-oxidation, microvessel endothelial protection, and proteopathy modification, are thought to be critical for its beneficial effects. This review describes the current evidence for the role of HDL in AD and the potential of using small peptides mimicking HDL or its associated apolipoproteins (HDL-mimetic peptides) as therapeutics to treat AD.

Mangosteen Pericarp and Its Bioactive Xanthones: Potential Therapeutic Value in Alzheimer's Disease, Parkinson's Disease, and Depression with Pharmacokinetic and Safety Profiles

Alzheimer's disease (AD), Parkinson's disease (PD), and depression are growing burdens for society globally, partly due to a lack of effective treatments. Mangosteen (Garcinia mangostana L.,) pericarp (MP) and its xanthones may provide therapeutic advantages for these disorders. In this review, we discuss potential therapeutic value of MP-derived agents in AD, PD, and depression with their pharmacokinetic and safety profiles. MP-derived agents have shown multifunctional effects including neuroprotective, antioxidant, and anti-neuroinflammatory actions. In addition, they target specific disease pathologies, such as amyloid beta production and deposition as well as cholinergic dysfunction in AD; α-synuclein aggregation in PD; and modulation of monoamine disturbance in depression. Particularly, the xanthone derivatives, including α-mangostin and γ-mangostin, exhibit potent pharmacological actions. However, low oral bioavailability and poor brain penetration may limit their therapeutic applications. These challenges can be overcome in part by administering as a form of MP extract (MPE) or using specific carrier systems. MPE and α-mangostin are generally safe and well-tolerated in animals. Furthermore, mangosteen-based products are safe for humans. Therefore, MPE and its bioactive xanthones are promising candidates for the treatment of AD, PD, and depression. Further studies including clinical trials are essential to decipher their efficacy, and pharmacokinetic and safety profiles in these disorders.

Tailored Reconstituted Lipoprotein for Site-Specific and Mitochondria-Targeted Cyclosporine A Delivery to Treat Traumatic Brain Injury

The secondary damage in traumatic brain injury (TBI) can lead to lifelong disabilities, bringing enormous economic and psychological burden to patients and their families. Mitochondria, as the core mediator of the secondary injury cascade reaction in TBI, is an important target to prevent the spread of cell death and dysfunction. Thus, therapeutics that can accumulate at the damaged sites and subsequently rescue the functions of mitochondria would largely improve the outcome of TBI. Cyclosporine A (CsA), which can maintain the integrity of mitochondrial function, is among the most promising neuroprotective therapeutics for TBI treatment. However, the clinical application of CsA in TBI is largely hindered because of its poor access to the targets. Here, to realize targeted intracellular CsA delivery, we designed a lipoprotein biomimetic nanocarrier by incorporating CsA in the core and decorating a matrix metalloproteinase-9 activatable cell-penetrating peptide onto the surface of the lipoprotein-mimic nanocarrier. This CsA-loaded tailored reconstituted lipoprotein efficiently accumulated at the damaged brain sites, entered the target cells, bound to the membrane of mitochondria, more efficiently reduced neuronal damage, alleviated neuroinflammation, and rescued memory deficits at the dose 1/16 of free CsA in a controlled cortical impact injury mice model. The findings provide strong evidence that the secondary damages in TBI can be well controlled through targeted CsA delivery and highlight the potential of a lipoprotein biomimetic nanocarrier as a flexible nanoplatform for the management of TBI.

Apoptosis induction by α-mangostin-loaded nanoparticles in human cervical carcinoma cells

The compound α-mangostin (AMG) extracted from Garcinia mangostana L. has potent anticancer properties but its clinical application is limited because of its poor solubility. In this study, AMG-loaded nanoparticles (NMG) were synthesized using a new formula and their apoptosis activity against human cervical carcinoma (HeLa) cells was investigated in comparison with organic solvent-soluble AMG in free form. The NMG was successfully synthesized with a particle size of <50 nm, polydispersity index <0.3, and zeta potential of -35.2 mV. At a concentration of 10 μg/mL, AMG reduced cell survival by 60%, whereas NMG treatment resulted in >90% cell death (p < 0.05). The AMG- or NMG-treated cells also showed changes in the size and shape and exhibited enhanced intensity of blue-stained nuclei, as well as decreased cell density, especially in NMG-treated cells. After 24 h of incubation with AMG or NMG, the cells went through late apoptosis at a rate of approximately 34% in 20 μg/mL AMG treatment and 27% in 10 μg/mL NMG treatment (p < 0.05). Thus, HeLa cells underwent more pronounced cell death through apoptosis induction caused by the NMG treatment compared to that caused by AMG. Clearly, the new NMG improved AMG bioavailability while maintaining the desired activity.

Neuronal mitochondria-targeted delivery of curcumin by biomimetic engineered nanosystems in Alzheimer's disease mice

Biomimetic nanotechnology represents a promising approach for the delivery of therapeutic agents for the treatment of complex diseases. Recently, neuronal mitochondria have been proposed to serve as a promising therapeutic target for sporadic Alzheimer's disease (AD). However, the efficient intravenous delivery of therapeutic agents to neuronal mitochondria in the brain remains a major challenge due to the complicated physiological and pathological environment. Herein, we devised and tested a strategy for functional antioxidant delivery to neuronal mitochondria by loading antioxidants into red blood cell (RBC) membrane-camouflaged human serum albumin nanoparticles bearing T807 and triphenylphosphine (TPP) molecules attached to the RBC membrane surface (T807/TPP-RBC-NPs). With the advantage of the suitable physicochemical properties of the nanoparticles and the unique biological functions of the RBC membrane, the T807/TPP-RBC-NPs are stabilized and promote sustained drug release, providing improved biocompatibility and long-term circulation. Under the synergistic effects of T807 and TPP, T807/TPP-RBC-NPs can not only penetrate the blood-brain barrier (BBB) but also target nerve cells and further localize in the mitochondria. After encapsulating curcumin (CUR) as the model antioxidant, the research data demonstrated that CUR-loaded T807/TPP-RBC-NPs can relieve AD symptoms by mitigating mitochondrial oxidative stress and suppressing neuronal death both in vitro and in vivo. In conclusion, the intravenous neuronal mitochondria-targeted biomimetic engineered delivery nanosystems provides an effective drug delivery platform for brain diseases. STATEMENT OF SIGNIFICANCE: The efficient intravenous delivery of therapeutic agents to neuronal mitochondria in the brain remains a major challenge for drug delivery due to the complicated physiological and pathological environment. To address this need, various types of nanovessels have been fabricated using a variety of materials in the last few decades. However, problems with the synthetic materials still exist and even cause toxicology issues. New findings in nanomedicine are promoting the development of biomaterials. Herein, we designed a red blood cell (RBC) membrane-coated human serum albumin nanoparticle dual-modified with T807 and TPP (T807/TPP-RBC-NPs) to accomplish these objectives. After encapsulating curcumin as the model drug, the research data demonstrated that the intravenous neuronal mitochondria-targeted biomimetic engineered delivery nanosystems are a promising therapeutic candidate for mitochondrial dysfunction in Alzheimer's disease (AD).

Nanoparticle Drug Delivery Systems for α-Mangostin

α-Mangostin, a xanthone derivative from the pericarp of Garcinia mangostana L., has numerous bioactivities and pharmacological properties. However, α-mangostin has low aqueous solubility and poor target selectivity in the human body. Recently, nanoparticle drug delivery systems have become an excellent technique to improve the physicochemical properties and effectiveness of drugs. Therefore, many efforts have been made to overcome the limitations of α-mangostin through nanoparticle formulations. Our review aimed to summarise and discuss the nanoparticle drug delivery systems for α-mangostin from published papers recorded in Scopus, PubMed and Google Scholar. We examined various types of nanoparticles for α-mangostin to enhance water solubility, provide controlled release and create targeted delivery systems. These forms include polymeric nanoparticles, nanomicelles, liposomes, solid lipid nanoparticles, nanofibers and nanoemulsions. Notably, nanomicelle modification increased α-mangostin solubility increased more than 10,000 fold. Additionally, polymeric nanoparticles provided targeted delivery and significantly enhanced the biodistribution of α-mangostin into specific organs. In conclusion, the nanoparticle drug delivery system could be a promising technique to increase the solubility, selectivity and efficacy of α-mangostin as a new drug candidate in clinical therapy.

Clearance of two organic nanoparticles from the brain via the paravascular pathway

The elaboration of nanotechnology offers valuable therapeutic options to overcome the blood-brain barrier and enable the treatment of brain diseases. However, to date, limit work has been done to reveal the fate of nanoparticles within the brain, which largely hinders their safe and effective applications. Here we demonstrated that the commonly-used organic nanoparticles reconstituted high density lipoprotein and poly(ethylene glycol)-b-poly(lactic acid) nanoparticles were cleared relatively fast from the brain (half-life <5 h). Notably, through various transgenic mice and pharmacological inhibition approaches, we revealed that the paravascular glymphatic pathway plays a key role (about 80%) in the brain clearance of the nanoparticles, and disclosed that microglia-mediated transportation is essential for facilitating nanoparticles elimination through the paravascular route. In addition, we witnessed a significant decline in the brain clearance of both of the nanoparticles in Alzheimer's model mice where the glymphatic system is impaired. These findings provide insightful data on the fate of nanoparticles in the brain, which would shed new light into the rational design and safe application of nanoparticles for brain drug delivery.

Sequential delivery of nanoformulated α-mangostin and triptolide overcomes permeation obstacles and improves therapeutic effects in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease exhibiting the poorest prognosis among solid tumors. The efficacy of conventional therapies has been hindered largely due to the insufficient chemotherapeutic delivery to the dense desmoplastic tumor stroma, and the extremely high or toxic dose needed for chemotherapy. Traditional Chinese Medicine (TCM) contains effective components that can effectively regulate tumor microenvironment and kill tumor cells, providing promising alternatives to PDAC chemotherapy. In this study, two active drug monomers of TCM were screened out and a sequentially targeting delivery regimen was developed to realize the optimized combinational therapy. Transforming growth factor-β (TGF-β) plays an indispensable role in promoting cancer-associated fibroblasts (CAFs) activation and proliferation, and CAFs have caused major physical barriers for chemotherapeutic drug delivery. Herein, CAFs-targeting biodegradable polymer nanoparticle (CRE-NP(α-M)) coated with CREKA peptide and loaded with TCM α-mangostin (α-M) was developed to modulate tumor microenvironment by interfering of TGF-β/Smad signaling pathway. Low pH-triggered micelle modified with CRPPR peptide and loaded with another TCM triptolide was constructed to increase the therapeutic effect of triptolide at the tumor sites and reduced its damage to main organs. As expected, CRE-NP(α-M) effectively inactived CAFs, reduced extracellular matrix production, promoted tumor vascular normalization and enhanced blood perfusion at the tumor site. The sequentially targeting drug delivery regimen, CRP-MC(Trip) following CRE-NP(α-M) pretreatment, exhibited strong tumor growth inhibition effect in the orthotopic tumor model. Hence, sequentially targeting delivery of nanoformulated TCM offers an efficient approach to overcome the permeation obstacles and improve the effect of chemotherapy on PDAC, and provides a novel option to treat desmoplastic tumors.