Lysosomes as a therapeutic target

Enhanced autophagic clearance of amyloid-β via histone deacetylase 6-mediated V-ATPase assembly and lysosomal acidification protects against Alzheimer's disease in vitro and in vivo

JOURNAL/nrgr/04.03/01300535-202509000-00025/figure1/v/2024-11-05T132919Z/r/image-tiff Recent studies have suggested that abnormal acidification of lysosomes induces autophagic accumulation of amyloid-β in neurons, which is a key step in senile plaque formation. Therefore, restoring normal lysosomal function and rebalancing lysosomal acidification in neurons in the brain may be a new treatment strategy for Alzheimer's disease. Microtubule acetylation/deacetylation plays a central role in lysosomal acidification. Here, we show that inhibiting the classic microtubule deacetylase histone deacetylase 6 with an histone deacetylase 6 shRNA or thehistone deacetylase 6 inhibitor valproic acid promoted lysosomal reacidification by modulating V-ATPase assembly in Alzheimer's disease. Furthermore, we found that treatment with valproic acid markedly enhanced autophagy, promoted clearance of amyloid-β aggregates, and ameliorated cognitive deficits in a mouse model of Alzheimer's disease. Our findings demonstrate a previously unknown neuroprotective mechanism in Alzheimer's disease, in which histone deacetylase 6 inhibition by valproic acid increases V-ATPase assembly and lysosomal acidification.

Current opinion on pluripotent stem cell technology in Gaucher's disease: challenges and future prospects

Gaucher's disease (GD) is a rare autosomal recessive genetic disorder caused by mutations in the GBA1 gene. Mutations in the gene lead to the deficiency of glucocerebrosidase, an enzyme that helps in the breakdown of glucosylceramide (GlcCer) into ceramide and glucose. The lack of the enzyme causes GlcCer accumulation in macrophages, resulting in various phenotypic characteristics of GD. The currently available therapies, including enzyme replacement therapy and substrate reduction therapy, only provide symptomatic relief. However, they grapple with limitations in efficacy, accessibility, and potential side effects. These observations laid the foundation to search for new approaches in the management of GD. Induced pluripotent stem cells (iPSCs) technology emerges as a beacon of hope, offering novel avenues for future GD therapies. The true magic of iPSCs lies in their ability to differentiate into various cell types. By reprogramming patient-derived cells into iPSCs, researchers can generate personalized models that recapitulate the genetic and phenotypic characteristics of the GD. These models are valuable tools for dissecting intricate disease pathways, developing novel therapeutic targets, and enhancing the drug development process for GD. This review emphasizes the significance of iPSCs technology in GD management. Further, it addresses several challenges that are being encountered in the application of iPSC technology in the management of GD. In addition, it provides several insights into the future aspects of iPSC technology in the management of GD.

Identification of immune characteristics between different subtypes in kidney renal clear cell carcinoma based on lysosome-related genes to assist immunotherapy

Previous studies have revealed the essential role of lysosomes in human diseases, including cancer. However, there is a lack of in-depth systematic research on its function in kidney renal clear cell carcinoma (KIRC). In this project, we collected the public dataset of KIRC and selected lysosomal genes tightly linked with survival. Cluster analysis uncovered that these genes possess good classification ability and can divide KIRC patients into multiple subtypes with different survival rates. Enrichment analyses revealed that the main biological processes associated with differentially expressed genes (DEGs) in the two representative subpopulations with the largest survival differences (cluster1 and cluster2) were steroid metabolic process, neutrophil extracellular trap formation, and tyrosine metabolism. The immune-related analysis demonstrated notable differences in immune cell infiltration levels between cluster1 and cluster2 subpopulations of KIRC. More specifically, Tfh and TIL were highly infiltrated in the cluster1, and Type II IFN response, mast cells, and basophils were highly infiltrated in the cluster2. The immunotherapy-related analysis demonstrated that cluster1 may be more sensitive to immunotherapy and more likely to benefit from immunotherapy due to its higher immune checkpoint expression, ESTIMATE score, immune score, and higher immunophenoscore (IPS). In addition, gene mutations occurred in the two subtypes, exhibiting similar mutation patterns between the two subtypes. Finally, based on the cMAP database, we identified some small molecules that may target DEGs between the two subtypes, such as epibatidine, mepyramine, and reboxetine. In conclusion, our investigation unearthed that different subtypes of KIRC patients exhibited different survival outcomes and sensitivity to the immune microenvironment, as well as different responses to immunotherapy. These findings may be beneficial for further mechanistic exploration and therapeutic research of KIRC in the future.

Mitochondrial dysfunction, cause or consequence in neurodegenerative diseases?

Neurodegenerative diseases encompass a spectrum of conditions characterized by the gradual deterioration of neurons in the central and peripheral nervous system. While their origins are multifaceted, emerging data underscore the pivotal role of impaired mitochondrial functions and endolysosomal homeostasis to the onset and progression of pathology. This article explores whether mitochondrial dysfunctions act as causal factors or are intricately linked to the decline in endolysosomal function. As research delves deeper into the genetics of neurodegenerative diseases, an increasing number of risk loci and genes associated with the regulation of endolysosomal and autophagy functions are being identified, arguing for a downstream impact on mitochondrial health. Our hypothesis centers on the notion that disturbances in endolysosomal processes may propagate to other organelles, including mitochondria, through disrupted inter-organellar communication. We discuss these views in the context of major neurodegenerative diseases including Alzheimer's and Parkinson's diseases, and their relevance to potential therapeutic avenues.

Itaconic acid ameliorates necrotizing enterocolitis through the TFEB-mediated autophagy-lysosomal pathway

Excessive autophagy has been implicated in the pathogenesis of necrotizing enterocolitis (NEC), yet the molecular underpinnings of the autophagy-lysosomal pathway (ALP) in NEC are not well characterized. This study aimed to elucidate alterations within the ALP in NEC by employing RNA sequencing on intestinal tissues obtained from affected infants. Concurrently, we established animal and cellular models of NEC to assess the therapeutic efficacy of itaconic acid (ITA). Our results indicate that the ALP is significantly disrupted in NEC. Notably, ITA was found to modulate the ALP, enhancing autophagic flux and lysosomal function, which consequently alleviated NEC symptoms. Further analysis revealed that ITA's beneficial effects are mediated through the promotion of TFEB nuclear translocation, thereby augmenting the ALP. These findings suggest that targeting the ALP with ITA to modulate TFEB activity may represent a viable therapeutic approach for NEC.

Prognostic prediction and immune infiltration analysis based on lysosome and senescence state identifies MMP12 as a novel therapy target in gastric cancer

BACKGROUND AND AIMS

As humans undergo the aging process, they become more vulnerable to various types of cancers, including gastric cancer (GC), which is frequently associated with aging. The senescent phenotype is closely linked to lysosomes, but research on the combined impact of senescence and lysosomes on GC prognosis is scarce.

METHODS

To construct and validate a prognostic model for gastric cancer (GC), we obtained gene expression and clinical data of GC patients from Cancer Genome Atlas (TCGA) databases. We employed Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression for model construction and ConsensusClusterPlus R package for generating cluster heatmaps. The model's predictive ability was evaluated through Kaplan-Meier survival analysis and ROC curve analysis. Our analysis included an assessment of the senescence and lysosome state using expression profiles and immune infiltration analysis through CIBERSORT methods. Finally, we validated potential gene targets through cellular experiments.

RESULTS

"In this research, we discovered two subtypes of gastric cancer (GC), Cluster 1 and Cluster 2. These subtypes are characterized by the presence of lysosomes and senescence, and we have identified distinct molecular features unique to each subtype. We observed that Cluster 2 had a lower survival prognosis compared to Cluster 1. Additionally, we have developed a risk prediction model that takes into consideration the presence of lysosomes and senescence. Patients in the high-risk group, as predicted by our model, experienced shorter survival times. Further analysis included immune infiltration, immune checkpoint, and chemotherapy evaluation of GC patients. We have displayed the frequency of mutations and copy number variations (CNVs) in visual formats. Our cellular experiments demonstrated that the MMP12 gene serves as a protective factor in GC cells."

CONCLUSIONS

In conclusion, we have clarified the extensive relationship between lysosomes and senescence in GC and developed a risk signature to forecast the prognosis of GC patients. MMP12 could be a promising protective factor for GC patients and might present a novel concept for anticipating the efficacy of targeted therapies and immunotherapies in GC patients.

Valence-dependent immune responses of earthworm coelomocytes: Toxicity pathways and molecular mechanisms of As (III) and As (V)-induced immunotoxicity

Epidemiological studies in inorganic arsenic (iAs) exposure populations have offered convincing evidence that exposure to arsenite (As (III)) and arsenate (As (V)) are linked to immune dysfunction and immunosuppression. However, the valence-dependent immunotoxicity mechanism of iAs has not been explored. In this work, we conducted a thorough investigation and comparison of lysosome dysfunction in As (III) and As (V) induced earthworm typical immune cells coelomocytes, and the binding reaction between As (III)/As (V) and immunoprotein lysozyme (LZM). Results indicated As (III) and As (V) induced severe alterations in NR uptake and caused serious damage to lysosomal membrane, particularly As (III). As (III) (21.24 %) had a stronger inhibitory effect on LZM activity in coelomocytes than As (V) (67.40 %), which showed a similar toxic trend as enzyme activity in vitro (As (III)-68.66 % and As (V)-78.50 %). LZM skeleton relaxation, secondary structural transformation, fluorescence sensitization and particle alteration provided evidence for As (III) trigger more grievous immunoprotein dysfunction. In conclusion, As (III) and As (V) triggered lysosomal membrane destruction in coelomocytes, as well as induced structural changes in LZM result in lysosomal hydrolase dysfunction in coelomocytes. Ultimately, cellular lysosome dysfunction and destruction, which leads to the normal immune system of the cells is disrupted. As (III) induced stronger immunosuppression through lysosome pathway than As (V). Our work reveals the degree of lysosome dysfunction triggered by As (III) and As (V) probably responsible for the valence-dependent immunosuppression patterns of iAs, and provide new insights for As toxicity assessment.

Spns1-dependent endocardial lysosomal function drives valve morphogenesis through Notch1-signaling

Autophagy-lysosomal degradation is a conserved homeostatic process considered to be crucial for cardiac morphogenesis. However, both its cell specificity and functional role during heart development remain unclear. Here, we introduced zebrafish models to visualize autophagic vesicles in vivo and track their temporal and cellular localization in the larval heart. We observed a significant accumulation of autolysosomal and lysosomal vesicles in the atrioventricular and bulboventricular regions and their respective valves. We addressed the role of lysosomal degradation based on the Spinster homolog 1 (spns1) mutant (not really started, nrs). n rs larvae displayed morphological and functional cardiac defects, including abnormal endocardial organization, impaired valve formation and retrograde blood flow. Single-nuclear transcriptome analyses revealed endocardial-specific differences in lysosome-related genes and alterations of notch1-signalling. Endocardial-specific overexpression of spns1 and notch1 rescued features of valve formation and function. Altogether, our results reveal a cell-autonomous role of lysosomal processing during cardiac valve formation affecting notch1-signalling.

Nanomedicine mediated thyroid cancer diagnosis and treatment: an approach from generalized to personalized medicine

Thyroid cancer (TC) being the common endocrine malignancy is glooming steadily due to its poor prognosis. The treatment strategies of surgery, radiotherapy, and conventional chemotherapy are providing unsatisfactory output. However, combination therapy can negotiate the worse prognosis to the better, where chemoradiotherapy, radiotherapy with surgery, or dual chemotherapeutic drugs are being glorified. Chemotherapy includes the use of doxorubicin or taxanes generally with platinum-based drugs viz. cisplatin or carboplatin that are administered alone or along with multitarget tyrosine kinase inhibitors viz. Lenvatinib, Sorafenib, Sunitinib, Vandetanib, Pyrazolo-pyrimidine compounds, etc., single target tyrosine kinase inhibitors like Dabrafenib plus Trametinib and Vemurafenib against BRAF, Gefitinib against EGFR, Everolimus against mTOR, vascular disruptors like Fosbretabulin, and immunotherapy with viz. Spartalizumab and Pembrolizumab, are anti-PD-1/PD-L1 molecules. Hence, several trials are currently evaluating the possible beneficial role of combinatorial therapy in TC. Since TC is the outcome of multiple genetic alterations, it necessitates targeting the multiple factors in a single shot. These combination strategies for systemically delivering therapeutic drugs seem feasible only with the help of theranostic. To date, nanoparticle-based drug delivery systems (NDDS) have devoted themselves to diagnosis, bioimaging, imaging-assisted surgery, and therapy with high success rates. The ease of handling hybrid technologies is also selectively admirable. However, in this review, we have summarized the sequential progression of chemotherapeutic drugs to NDDS designed for Personalized Medicine (PM) against TC. Personalized medicine is an ever-growing field that will be explored in future discoveries in biomedicine, particularly cancer theranostics. Hence, our review presents a closer view of NDDS as a personalized treatment for TC. We have also discussed the primary challenges facing NDDS in meeting excellence in PM.

A correlation of polymorphic G-quadruplex formation in vitro and in the lysosomes of live cancer cells

Guanine-rich oligonucleotides (GROs) can fold into G-quadruplex (G4) structures. The diverse roles of G4 structures, particularly as targets for drug design, anticancer agents, and drug delivery systems, highlight their critical significance in cancer research. However, the formation of G4 structures is highly dependent on the specific nucleotide sequences and the number of G-tracts within each GRO. In vitro studies using circular dichroism (CD), nuclear magnetic resonance (NMR), and polyacrylamide gel electrophoresis (PAGE) demonstrated that GROs with fewer than four G-tracts can form intermolecular G4 structures in K+ solution at 37 °C. In fluorescence lifetime imaging microscopy study, intermolecular parallel G4 structures, formed by single-stranded GROs containing three G-tracts with three guanines each, were observed to be detectable in the lysosomes of live CL1-0 cancer cells. In contrast, a mutated sequence with only two G-tracts was rarely detected in the lysosomes of CL1-0 cancer cells, highlighting its incapability of forming intermolecular parallel G4s. Furthermore, polymorphic G4 formation in vitro and in-cell studies revealed a potential correlation. Our findings demonstrate that exogenous GROs can be introduced to explore the structural dynamics of G4 formation in live cancer cells, as well as their potential as anticancer agents and drug delivery carriers targeting lysosomes.

The use of nanocarriers in treating Batten disease: A systematic review

The neuronal ceroid lipofuscinoses, commonly known as Batten disease, are a group of lysosomal storage disorders affecting children. There is extensive central nervous system and retinal degeneration, resulting in seizures, vision loss and a progressive cognitive and motor decline. Enzyme replacement and gene therapies are being developed, and mRNA and oligonucleotide therapies are more recently being considered. Overcoming the challenges of the blood-brain barrier and blood-ocular barrier is crucial for effectively targeting the brain and eye, whatever the therapeutic approach. Nanoparticles and extracellular vesicles are small carriers that can encapsulate a cargo and pass through these cell barriers. They have been investigated as drug carriers for other pathologies and could be a promising treatment strategy for Batten disease. Their use in gene, enzyme, or mRNA replacement therapy of all lysosomal storage disorders, including Mucopolysaccharidoses, Niemann-Pick diseases, and Fabry disease, is investigated in this systematic review. Different nanocarriers can efficiently target the lysosome and cross the barriers into the brain and eyes. This supports continued exploration of nanocarriers as potential future treatment options for Batten disease.

Application of acid-activated near-infrared viscosity fluorescent probe targeting lysosomes in cancer visualization

The higher viscosity and lower pH in lysosomes of cancer cells highlight their potential as biomarkers for cancer. Therefore, the development of acid-activated viscosity fluorescent probes is significant for the early diagnosis and treatment of cancer. Based on this, we have designed and synthesized a near-infrared fluorescent probe based on the 2-(2-hydroxyphenyl)benzothiazole (HBT) group, namely HBTH, to monitor the viscosity changes within lysosomes. It has been demonstrated that HBTH was extremely sensitive to viscosity, with a strong linear relationship between fluorescence intensity and log(viscosity) within the range of (logη) = 0-3.06 (a correlation coefficient of 0.98), proving its capability for quantitative viscosity measurement. In particular, the most obvious fluorescence enhancement of HBTH was only efficiently triggered by the combined effect of low pH and high viscosity. Furthermore, HBTH can rapidly localize to lysosomes by wash-free procedure at a low concentration (100 nM) and achieve high-fidelity imaging within 20 s. It can also monitor the dynamic processes of lysosomes in cells, viscosity changes under drug stimuli, and lysosomal behavior during mitophagy. Importantly, HBTH is capable of identifying tumors in tumor-bearing nude mice through in vivo imaging. These features make HBTH a powerful tool for the early diagnosis and treatment of cancer.

Discovery of sp3-rich diazatricycloundecanes as lysosomotropic autophagy inhibitors

We have discovered lysosomotropic autophagy inhibitors from our compound library of sp3-rich diazatricycloundecane skeletons. Compound 1u was identified as the most potent biological activity for LC3-II protein accumulation through the structure-activity relationships (SARs) for LC3-II protein accumulation and anti-proliferative activity at the three freely available substituents (R1-R3) in the diazatricycloundecane skeleton. Compound 1u inhibited lysosome-dependent degradation without affecting autophagosome formation. Furthermore, compound 1u enlarged lysosomes and raised lysosomal pH similar to lysosomotropic agents such as chloroquine, resulting in inhibiting late-stage autophagy by inducing lysosomal dysfunction. Moreover, compound 1u exhibits excellent drug-like chemical properties, not previously reported for lysosomotropic agents.

Tumor-Targeted Catalytic Immunotherapy

Cancer immunotherapy holds significant promise for improving cancer treatment efficacy; however, the low response rate remains a considerable challenge. To overcome this limitation, advanced catalytic materials offer potential in augmenting catalytic immunotherapy by modulating the immunosuppressive tumor microenvironment (TME) through precise biochemical reactions. Achieving optimal targeting precision and therapeutic efficacy necessitates a thorough understanding of the properties and underlying mechanisms of tumor-targeted catalytic materials. This review provides a comprehensive and systematic overview of recent advancements in tumor-targeted catalytic materials and their critical role in enhancing catalytic immunotherapy. It highlights the types of catalytic reactions, the construction strategies of catalytic materials, and their fundamental mechanisms for tumor targeting, including passive, bioactive, stimuli-responsive, and biomimetic targeting approaches. Furthermore, this review outlines various tumor-specific targeting strategies, encompassing tumor tissue, tumor cell, exogenous stimuli-responsive, TME-responsive, and cellular TME targeting strategies. Finally, the discussion addresses the challenges and future perspectives for transitioning catalytic materials into clinical applications, offering insights that pave the way for next-generation cancer therapies and provide substantial benefits to patients in clinical settings.

Autophagy-Mediated Targeted Protein Degradation

Autophagy is an evolutionarily conserved turnover process in eukaryotes, mediating the delivery of various cellular components to lysosomes for degradation and facilitating the recycling of the breakdown products to maintain homeostasis. By harnessing this powerful autophagy-lysosomal degradation system, strategies for targeted protein degradation (TPD) have been emerging to remove specific disease-related proteins (both intracellular and cell-surface proteins) for complete elimination of their functions, bringing new insights to drug discovery. Herein, we give a brief introduction on how autophagy works followed by a focus on available small-molecule and macromolecule-based strategies for TPD mediated by autophagy.

A novel dicyanoisophorone-based fluorescent probe for rapid detection of acetylcholinesterase in biological systems

Acetylcholinesterase (AChE) plays a vital role in various neurological diseases including brain disorders, neurotransmission alterations, and cancer. Developing effective methods to image AChE in biological samples is essential for understanding its mechanisms in biosystems. Here, we introduce a novel fluorescent probe CNA, that enables detection of AChE at 520 nm with rapid response time of 60 s and a detection limit of 0.014 U/mL. We successfully applied CNA to image endogenous and exogenous AChE in PC12 cells and in living mice. These findings highlight the potential of CNA as an effective method to study the physiological and pathological roles of AChE in complex living systems.

Advances in drug delivery systems utilizing blood cells and their membrane-derived microvesicles

The advancement of drug delivery systems (DDSs) in recent decades has demonstrated significant potential in enhancing the efficacy of pharmacological agents. Despite the approval of certain DDSs for clinical use, challenges such as rapid clearance from circulation, toxic accumulation in the body, and ineffective targeted delivery persist as obstacles to successful clinical application. Blood cell-based DDSs have emerged as a popular strategy for drug administration, offering enhanced biocompatibility, stability, and prolonged circulation. These DDSs are well-suited for systemic drug delivery and have played a crucial role in formulating optimal drug combinations for treating a variety of diseases in both preclinical studies and clinical trials. This review focuses on recent advancements and applications of DDSs utilizing blood cells and their membrane-derived microvesicles. It addresses the current therapeutic applications of blood cell-based DDSs at the organ and tissue levels, highlighting their successful deployment at the cellular level. Furthermore, it explores the mechanisms of cellular uptake of drug delivery vectors at the subcellular level. Additionally, the review discusses the opportunities and challenges associated with these DDSs.

Lysosome-localization and tumor-targeting of novel photosensitizers enhance the ablation of cancer

Lysosomes are promising therapeutic targets for cancer therapy due to their essential function and increased vulnerability in cancer cells. Herein, we report a new category of cationic photosensitizers (compounds 1-3) containing a quaternary ammonium group. These photosensitizers exhibited selective uptake on cancer cells (about three times compared to the normal cells), lysosome-specific localization (Pearson's coefficients greater than 0.85), remarkable phototoxicity (IC50 are in the range of dozens of nM), and at the same time, favorable biosafety. Mechanically, these tumor-targeting photosensitizers function as light-controlled "bombs", inducing lysosomal membrane permeabilization (LMP), ultimately resulting in apoptosis of cancer cells. In vivo, compound 1 (a representative of these novel photosensitizers) accumulated predominantly in and visualized tumors implanted on mice. Upon exposure to near-infrared light irradiation (50 J/cm2), the compound effectively ablated the tumor at a low dose of 2 mg/kg. Our results demonstrate a novel class of photosensitizers showing potential for integrated cancer diagnosis and photodynamic treatment.

TRPML1 agonist ML-SA5 mitigates uranium-induced nephrotoxicity via promoting lysosomal exocytosis

Uranium (U) released from U mining and spent nuclear fuel reprocessing in the nuclear industry, nuclear accidents and military activities as a primary environmental pollutant (e.g., drinking water pollution) is a threat to human health. Kidney is one of the main target organs for U accumulation, leading to nephrotoxicity mainly associated with the injuries in proximal tubular epithelial cells (PTECs). Transient receptor potential mucolipin 1 (TRPML1) is a novel therapeutic target for nephrotoxicity caused by acute or chronic U poisoning. We herein investigate the therapeutic efficacy of ML-SA5, a small molecule agonist of TRPML1, in U-induced nephrotoxicity in acute U intoxicated mice. We demonstrate that delayed treatment with ML-SA5 enhances U clearance from the kidneys via urine excretion by activating lysosomal exocytosis, and thereby attenuates U-induced kidney dysfunction and cell death/apoptosis of renal PTECs in acute U intoxicated mice. In addition, ML-SA5 promotes the nuclear translocation of transcription factor EB (TFEB) in renal PTECs in acute U intoxicated mice. Mechanistically, ML-SA5 triggers the TRPML1-mediated lysosomal calcium release and consequently induces TFEB activation in U-loaded renal PTECs-derived HK-2 cells. Moreover, knockdown of TRPML1 or TFEB abolishes the effects of ML-SA5 on the removal of intracellular U and reduction of the cellular injury/death in U-loaded HK-2 cells. Our findings indicate that pharmacological activation of TRPML1 is a promising therapeutic approach for the delayed treatment of U-induced nephrotoxicity via the activation of the positive feedback loop of TRPML1 and TFEB and consequent the induction of lysosomal exocytosis.

Integration of transcriptional and epigenetic regulation of TFEB reveals its dual functional roles in Pan-cancer

Transcription factor EB (TFEB) mainly regulates the autophagy-lysosomal pathway, associated with many diseases, including cancer. However, the role of TFEB in pan-cancer has not been investigated systematically. In this study, we comprehensively analyzed TFEB targets under three stresses in Hela cells by cross-validation of RNA-seq and ChIP-seq. 1712 novel TFEB targets have not been reported in the Gene Set Enrichment Analysis and ChIP Enrichment Analysis databases. We further investigated their distributions and roles among the pan-cancer co-expression networks across 32 cancers constructed by multiscale embedded gene co-expression network analysis (MEGENA) based on the Cancer Genome Atlas (TCGA) cohort. Specifically, TFEB might serve as a hidden player with multifaceted functions in regulating pan-cancer risk factors, e.g. CXCL2, PKMYT1 and BUB1, associated with cell cycle and immunosuppression. TFEB might also regulate protective factors, e.g. CD79A, related to immune promotion in the tumor microenvironment. We further developed a Shiny app website to present the comprehensive regulatory targets of TFEB under various stimuli, intending to support further research on TFEB functions. Summarily, we provided references for the TFEB downstream targets responding to three stresses and the dual roles of TFEB and its targets in pan-cancer, which are promising anticancer targets that warrant further exploration.

Calcium signaling from damaged lysosomes induces cytoprotective stress granules

Lysosomal damage induces stress granule (SG) formation. However, the importance of SGs in determining cell fate and the precise mechanisms that mediate SG formation in response to lysosomal damage remain unclear. Here, we describe a novel calcium-dependent pathway controlling SG formation, which promotes cell survival during lysosomal damage. Mechanistically, the calcium-activated protein ALIX transduces lysosomal damage signals to SG formation by controlling eIF2α phosphorylation after sensing calcium leakage. ALIX enhances eIF2α phosphorylation by promoting the association between PKR and its activator PACT, with galectin-3 inhibiting this interaction; these regulatory events occur on damaged lysosomes. We further find that SG formation plays a crucial role in promoting cell survival upon lysosomal damage caused by factors such as SARS-CoV-2ORF3a, adenovirus, malarial pigment, proteopathic tau, or environmental hazards. Collectively, these data provide insights into the mechanism of SG formation upon lysosomal damage and implicate it in diseases associated with damaged lysosomes and SGs.

Human VCP mutant ALS/FTD microglia display immune and lysosomal phenotypes independently of GPNMB

BACKGROUND

Microglia play crucial roles in maintaining neuronal homeostasis but have been implicated in contributing to amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). However, the role of microglia in ALS/FTD remains incompletely understood.

METHODS

Here, we generated highly enriched cultures of VCP mutant microglia derived from human induced pluripotent stem cells (hiPSCs) to investigate their cell autonomous and non-cell autonomous roles in ALS pathogenesis. We used RNA-sequencing, proteomics and functional assays to study hiPSC derived VCP mutant microglia and their effects on hiPSC derived motor neurons and astrocytes.

RESULTS

Transcriptomic, proteomic and functional analyses revealed immune and lysosomal dysfunction in VCP mutant microglia. Stimulating healthy microglia with the inflammatory inducer lipopolysaccharide (LPS) showed partial overlap with VCP mutant microglia in their reactive transformation. LPS-stimulated VCP mutant microglia displayed differential activation of inflammatory pathways compared with LPS-stimulated healthy microglia. Conserved gene expression changes were identified between VCP mutant microglia, SOD1 mutant mice microglia, and postmortem ALS spinal cord microglial signatures, including increased expression of the transmembrane glycoprotein GPNMB. While knockdown of GPNMB affected inflammatory and phagocytosis processes in microglia, this was not sufficient to ameliorate cell autonomous phenotypes in VCP mutant microglia. Secreted factors from VCP mutant microglia were sufficient to activate the JAK-STAT pathway in hiPSC derived motor neurons and astrocytes.

CONCLUSIONS

VCP mutant microglia undergo cell autonomous reactive transformation involving immune and lysosomal dysfunction that partially recapitulate key phenotypes of microglia from other ALS models and post mortem tissue. These phenotypes occur independently of GPNMB. Additionally, VCP mutant microglia elicit non cell autonomous responses in motor neurons and astrocytes involving the JAK-STAT pathway.

Precise Regulations at the Subcellular Level through Intracellular Polymerization, Assembly, and Transformation

A living cell is an intricate machine that creates subregions to operate cell functions effectively. Subcellular dysfunction has been identified as a potential druggable target for successful drug design and therapy. The treatments based on intracellular polymerization, self-assembly, or transformation offer various advantages, including enhanced blood circulation of monomers, long-term drug delivery pharmacokinetics, low drug resistance, and the ability to target deep tissues and organelles. In this review, we discuss the latest developments of intracellular synthesis applied to precisely control cellular functions. First, we discuss the design and applications of endogenous and exogenous stimuli-triggered intracellular polymerization, self-assembly, and dynamic morphology transformation of biomolecules at the subcellular level. Second, we highlight the benefits of these strategies applied in cancer diagnosis and treatment and modulating cellular states or cell metabolism of living systems. Finally, we conclude the recent progress in this field, discuss future perspectives, analyze the challenges of the intracellular functional reactions for regulation, and find future opportunities.

Regulation of lysosomes in skeletal muscle during exercise, disuse and aging

Lysosomes play a critical role as a terminal organelle in autophagy flux and in regulating protein degradation, but their function and adaptability in skeletal muscle is understudied. Lysosome functions include both housekeeping and signaling functions essential for cellular homeostasis. This review focuses on the regulation of lysosomes in skeletal muscle during exercise, disuse, and aging, with a consideration of sex differences as well as the role of lysosomes in mediating the degradation of mitochondria, termed mitophagy. Exercise enhances mitophagy during elevated mitochondrial stress and energy demand. A critical response to this deviation from homeostasis is the activation of transcription factors TFEB and TFE3, which drive the expression of lysosomal and autophagic genes. Conversely, during muscle disuse, the suppression of lysosomal activity contributes to the accumulation of defective mitochondria and other cellular debris, impairing muscle function. Aging further exacerbates these effects by diminishing lysosomal efficacy, leading to the accumulation of damaged cellular components. mTORC1, a key nutrient sensor, modulates lysosomal activity by inhibiting TFEB/TFE3 translocation to the nucleus under nutrient-rich conditions, thereby suppressing autophagy. During nutrient deprivation or exercise, AMPK activation inhibits mTORC1, facilitating TFEB/TFE3 nuclear translocation and promoting lysosomal biogenesis and autophagy. TRPML1 activation by mitochondrial ROS enhances lysosomal calcium release, which is essential for autophagy and maintaining mitochondrial quality. Overall, the intricate regulation of lysosomal functions and signaling pathways in skeletal muscle is crucial for adaptation to physiological demands, and disruptions in these processes during disuse and aging underscore the ubiquitous power of exercise-induced adaptations, and also highlight the potential for targeted therapeutic interventions to preserve muscle health.

Chemical and Biological Properties of Different Romanian Populations of Hyssopus officinalis Correlated via Molecular Docking

This study compares three Romanian Hyssopus officinalis species-H. officinalis f. ruber (HOR), H. officinalis f. albus (HOA), and H. officinalis f. cyaneus (HOC)-evaluating their chemical composition and biological activities, specifically protein denaturation, haemolysis inhibition, and antibacterial effects. Chemical profiles were determined using Gas Chromatography-Mass Spectrometry (GC-MS). The species were cultivated at two distinct locations: the Didactic and Experimental Station DESUSVT and the Agricultural Research and Development Station Lovrin (ARDSL). This study investigates the correlation between chemical composition, biological activities, and local climate data at each site. The results show significant variations in chemical profiles, with species and cultivation location influencing the biological activities. H. officinalis f. albus (HOA) exhibited the strongest antimicrobial activity, particularly against Gram-positive bacteria. The molecular docking analysis highlighted key compounds, such as cyclohexene,4-isopropenyl-1-methoxymethoxymethyl and elemol, with binding solid affinities to microbial and inflammatory proteins. This study provides valuable insights into the chemical and biological properties of Hyssopus officinalis, emphasising its potential in combating microbial infections, protein denaturation, and haemolysis inhibition.

Targeted protein degradation: advances in drug discovery and clinical practice

Targeted protein degradation (TPD) represents a revolutionary therapeutic strategy in disease management, providing a stark contrast to traditional therapeutic approaches like small molecule inhibitors that primarily focus on inhibiting protein function. This advanced technology capitalizes on the cell's intrinsic proteolytic systems, including the proteasome and lysosomal pathways, to selectively eliminate disease-causing proteins. TPD not only enhances the efficacy of treatments but also expands the scope of protein degradation applications. Despite its considerable potential, TPD faces challenges related to the properties of the drugs and their rational design. This review thoroughly explores the mechanisms and clinical advancements of TPD, from its initial conceptualization to practical implementation, with a particular focus on proteolysis-targeting chimeras and molecular glues. In addition, the review delves into emerging technologies and methodologies aimed at addressing these challenges and enhancing therapeutic efficacy. We also discuss the significant clinical trials and highlight the promising therapeutic outcomes associated with TPD drugs, illustrating their potential to transform the treatment landscape. Furthermore, the review considers the benefits of combining TPD with other therapies to enhance overall treatment effectiveness and overcome drug resistance. The future directions of TPD applications are also explored, presenting an optimistic perspective on further innovations. By offering a comprehensive overview of the current innovations and the challenges faced, this review assesses the transformative potential of TPD in revolutionizing drug development and disease management, setting the stage for a new era in medical therapy.

Synthetic Nanoassemblies for Regulating Organelles: From Molecular Design to Precision Therapeutics

Each organelle referring to a complex multiorder architecture executes respective biological processes via its distinct spatial organization and internal microenvironment. As the assembly of biomolecules is the structural basis of living cells, creating synthetic nanoassemblies with specific physicochemical and morphological properties in living cells to interfere or couple with the natural organelle architectures has attracted great attention in precision therapeutics of cancers. In this review, we give an overview of the latest advances in the synthetic nanoassemblies for precise organelle regulation, including the formation mechanisms, triggering strategies, and biomedical applications in precision therapeutics. We summarize the emerging material systems, including polymers, peptides, and deoxyribonucleic acids (DNAs), and their respective intermolecular interactions for intercellular synthetic nanoassemblies, and highlight their design principles in constructing precursors that assemble into synthetic nanoassemblies targeting specific organelles in the complex cellular environment. We further showcase the developed intracellular synthetic nanoassemblies targeting specific organelles including mitochondria, the endoplasmic reticulum, lysosome, Golgi apparatus, and nucleus and describe their underlying mechanisms for organelle regulation and precision therapeutics for cancer. Last, the essential challenges in this field and prospects for future precision therapeutics of synthetic nanoassemblies are discussed. This review should facilitate the rational design of organelle-targeting synthetic nanoassemblies and the comprehensive recognition of organelles by materials and contribute to the deep understanding and application of the synthetic nanoassemblies for precision therapeutics.

Critical role of ROCK1 in AD pathogenesis via controlling lysosomal biogenesis and acidification

BACKGROUND

Lysosomal homeostasis and functions are essential for the survival of neural cells. Impaired lysosomal biogenesis and acidification in Alzheimer's disease (AD) pathogenesis leads to proteolytic dysfunction and neurodegeneration. However, the key regulatory factors and mechanisms of lysosomal homeostasis in AD remain poorly understood.

METHODS

ROCK1 expression and its co-localization with LAMP1 and SQSTM1/p62 were detected in post-mortem brains of healthy controls and AD patients. Lysosome-related fluorescence probe staining, transmission electron microscopy and immunoblotting were performed to evaluate the role of ROCK1 in lysosomal biogenesis and acidification in various neural cell types. The interaction between ROCK1 and TFEB was confirmed by surface plasmon resonance and in situ proximity ligation assay (PLA). Moreover, we performed AAV-mediated ROCK1 downregulation followed by immunofluorescence, enzyme-linked immunosorbent assay (ELISA) and behavioral tests to unveil the effects of the ROCK1-TFEB axis on lysosomes in APP/PS1 transgenic mice.

RESULTS

ROCK1 level was significantly increased in the brains of AD individuals, and was positively correlated with lysosomal markers and Aβ. Lysosomal proteolysis was largely impaired by the high abundance of ROCK1, while ROCK1 knockdown mitigated the lysosomal dysfunction in neurons and microglia. Moreover, we verified ROCK1 as a previously unknown upstream kinase of TFEB independent of m-TOR or GSK-3β. ROCK1 elevation resulted in abundant extracellular Aβ deposition which in turn bound to Aβ receptors and activated RhoA/ROCK1, thus forming a vicious circle of AD pathogenesis. Genetically downregulating ROCK1 lowered its interference with TFEB, promoted TFEB nuclear distribution, lysosomal biogenesis and lysosome-mediated Aβ clearance, and eventually prevented pathological traits and cognitive deficits in APP/PS1 mice.

CONCLUSION

In summary, our results provide a mechanistic insight into the critical role of ROCK1 in lysosomal regulation and Aβ clearance in AD by acting as a novel upstream serine kinase of TFEB.

Lysosome-Targeted Bifunctional Therapeutics Induce Autodynamic Cancer Therapy

Autodynamic cancer therapy possesses tremendous potential for enhancing therapeutic efficacy by initiating the treatment process autonomously within targeted cells. However, challenges related to biocompatibility and targeted delivery have hindered its clinical translation owing to the induction of adverse effects and cytotoxicity in healthy cells. In this study, a novel approach for auto-initiated dynamic therapy by conjugating zwitterionic near-infrared fluorophores to a cell-penetrating peptide is proposed. This enables efficient cellular uptake and specific targeting of therapy to desired cells while avoiding off-target uptake. The zwitterionic bioconjugate causes cancer-specific toxicity following its internalization into the targeted cells, triggered by specific intracellular conditions in lysosomes. This innovative approach enables selective targeting of lysosomes in malignant cells while minimizing cytotoxic effects on normal cells. By targeting lysosomes, the method overcomes inherent risks and side effects associated with conventional cancer treatments, offering a selective and effective approach to cancer therapy.

Mechanisms of autophagy-lysosome dysfunction in neurodegenerative diseases

Autophagy is a lysosome-based degradative process used to recycle obsolete cellular constituents and eliminate damaged organelles and aggregate-prone proteins. Their postmitotic nature and extremely polarized morphologies make neurons particularly vulnerable to disruptions caused by autophagy-lysosomal defects, especially as the brain ages. Consequently, mutations in genes regulating autophagy and lysosomal functions cause a wide range of neurodegenerative diseases. Here, we review the role of autophagy and lysosomes in neurodegenerative diseases such as Alzheimer disease, Parkinson disease and frontotemporal dementia. We also consider the strong impact of cellular ageing on lysosomes and autophagy as a tipping point for the late-age emergence of related neurodegenerative disorders. Many of these diseases have primary defects in autophagy, for example affecting autophagosome formation, and in lysosomal functions, especially pH regulation and calcium homeostasis. We have aimed to provide an integrative framework for understanding the central importance of autophagic-lysosomal function in neuronal health and disease.

Visualizing lysosomes hypochlorous acid in Parkinson's disease models by a novel fluorescent probe

Heightened oxidative stress is the principal driver behind the altered metabolism of neurotransmitters within the brains of Parkinson's disease (PD). Hypochlorous acid (HClO), a variant of reactive oxygen species (ROS), plays a crucial role in several lysosomal activities. An irregular concentration of HClO may result in significant molecular damage and contribute to the onset of neurodegenerative disorders. Despite this, the precise role of lysosomal HClO in PD remains unclear, due to its fast reactivity and low levels. This is further complicated by the lack of effective in situ imaging techniques for accurately tracking its dynamics. Therefore, it is of great significance to use effective tools to map the lysosomal HClO during the pathological process of PD. In this study, we propose a fluorogenic probe named Lys-PTZ-HClO for the specific and sensitive detection of HClO. Lys-PTZ-HClO exhibits features like a fast response time (10 s) and a low detection limit (0.72 μM). Benefiting from its superior properties, the probe was used to visualize the basal HClO levels, and the variation of HClO levels in lysosomal of living cells. More importantly, this probe was successfully applied for the first time to reveal increased lysosomal HClO in a cellular model of PD.

The role of host autophagy in intracellular protozoan parasites diseases

Intracellular protozoan parasites are the etiologic agents of important human diseases, like malaria, Chagas disease, toxoplasmosis, and leishmaniasis. Inside host cells, these parasites manipulate the host metabolism and intracellular trafficking for their own benefits and, inevitably, induce several stress response mechanisms. In this review, we discuss autophagy as a stress response mechanism that can be both (i) explored by these intracellular parasites to acquire nutrients and (ii) to restrict parasite proliferation and survival within host cells. We also discuss the immunomodulatory role of autophagy as a strategy to reduce inflammatory-mediated damage, an essential player in the pathophysiology of these parasitic diseases. At last, we propose and discuss several known autophagy modulators as possible pharmaceuticals for adjunctive therapies.

Lysosome Targeted Nanoparticle Aggregation Reverses Immunosuppressive Tumor Microenvironment for Cancer Immunotherapy

Nanotechnology has proven its enormous application value in clinical practice. However, current research on nanomedicines mainly focuses on developing nanoparticles as delivery carriers to maximize the bioavailability of therapeutic agents, with little attention on exploring their potential to directly regulate physiological processes. In this study, inspired by the lysosomal swelling caused by excessive accumulation of undegraded substances, this work presents a lysosomal-targeting aggregated nanoparticle (LTANP) for cancer treatment. By rationally engineering surface composition, properties, and interparticle interactions, LTANP achieves efficient tumor accumulation and selective targeted aggregation in lysosomes of cancer cells, leading to unrelievable lysosomal swelling, and ultimately inducing lysosomal membrane permeabilization (LMP) of cancer cells. Further analysis shows that nanoparticle aggregation-mediated LMP can effectively trigger immunogenic cell death (ICD) by impairing autophagy-lysosome pathway, evoking robust antitumor immune responses and reversing tumor immunogenicity from "cold" to "hot" in a melanoma model. Additionally, LTANP can combine with clinically approved programmed death ligand-1 (PD-L1) antibodies to further unleash T cell-mediated antitumor immunity, significantly enhancing antitumor performance, inhibiting tumor recurrence and metastasis. This work demonstrates the potential of rationally engineered nanostructures in directly combating cancer and provides novel insights for the development of advanced nanoparticle-based cancer treatment.

Mechanisms of extracellular vesicle uptake and implications for the design of cancer therapeutics

The translation of pre-clinical anti-cancer therapies to regulatory approval has been promising, but slower than hoped. While innovative and effective treatments continue to achieve or seek approval, setbacks are often attributed to a lack of efficacy, failure to achieve clinical endpoints, and dose-limiting toxicities. Successful efforts have been characterized by the development of therapeutics designed to specifically deliver optimal and effective dosing to tumour cells while minimizing off-target toxicity. Much effort has been devoted to the rational design and application of synthetic nanoparticles to serve as targeted therapeutic delivery vehicles. Several challenges to the successful application of this modality as delivery vehicles include the induction of a protracted immune response that results in their rapid systemic clearance, manufacturing cost, lack of stability, and their biocompatibility. Extracellular vesicles (EVs) are a heterogeneous class of endogenous biologically produced lipid bilayer nanoparticles that mediate intercellular communication by carrying bioactive macromolecules capable of modifying cellular phenotypes to local and distant cells. By genetic, chemical, or metabolic methods, extracellular vesicles (EVs) can be engineered to display targeting moieties on their surface while transporting specific cargo to modulate pathological processes following uptake by target cell populations. This review will survey the types of EVs, their composition and cargoes, strategies employed to increase their targeting, uptake, and cargo release, and their potential as targeted anti-cancer therapeutic delivery vehicles.

Inclusion body myositis: Correcting impaired mitochondrial and lysosomal autophagy as a potential therapeutic strategy

Inclusion body myositis (IBM) is a late onset sporadic myopathy with a characteristic clinical presentation, but as yet unknown aetiology or effective treatment. Typical clinical features are early predominant asymmetric weakness of finger flexor and knee extensor muscles. Muscle biopsy shows endomysial inflammatory infiltrate, mitochondrial changes, and protein aggregation. Proteostasis (protein turnover) appears to be impaired, linked to potentially dysregulated chaperone-mediated autophagy and mitophagy (a type of mitochondrial quality control). In this review, we bring together the most recent clinical and biological data describing IBM. We then address the question of diagnosing this pathology and the relevance of the current biological markers that characterize IBM. In these descriptions, we put a particular emphasis on data related to the deregulation of autophagic processes and to the mitochondrial-lysosomal crosstalk. Finally, after a short description of current treatments, an overview is provided pointing towards novel therapeutic targets and emerging regulatory molecules that are being explored for treating IBM. Special attention is paid to autophagy inhibitors that may offer innovative breakthrough therapies for patients with IBM.

Emerging Molecular-Genetic Families in Dystonia: Endosome-Autophagosome-Lysosome and Integrated Stress Response Pathways

Advances in genetic technologies and disease modeling have greatly accelerated the pace of introducing and validating molecular-genetic contributors to disease. In dystonia, there is a growing convergence across multiple distinct forms of the disease onto core biological processes. Here, we discuss two of these, the endosome-autophagosome-lysosome pathway and the integrated stress response, to highlight recent advances in the field. Using these two pathomechanisms as examples, we further discuss the opportunities that molecular-genetic grouping of dystonias present to transform dystonia care. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Allergic reactions to enzyme replacement therapy in children with lysosomal storage diseases and their management

OBJECTIVES

Human recombinant enzyme replacement therapy, given to compensate for genetic enzyme deficiency in lysosomal storage diseases, delays the progression of the disease and improves the quality of life. However, enzyme replacement therapy may cause hypersensitivity reactions. Within the scope of this research, we aimed to elucidate the frequency and clinical features of hypersensitivity reactions against enzyme replacement therapy in children with lysosomal storage diseases and clarify the management of these reactions.

METHODS

Medical records of pediatric patients with lysosomal storage disease and receiving enzyme replacement therapy were retrospectively reviewed, and patients who experienced allergic reactions were included in the study. The demographic characteristics of the patients, their diagnosis, the responsible enzyme, the time at which the reaction started and at what dose, the signs and symptoms associated with the reaction, diagnostic tests, the management of the reaction, and the protocol applied for the maintenance of enzyme replacement therapy after the reaction were recorded.

RESULTS

Hypersensitivity reactions developed in 18 of 71 patients (25.3 %) who received enzyme replacement therapy. The most common cutaneous findings were observed. Anaphylaxis developed in 6 of 18 patients. Patients who experienced recurrent hypersensitivity reactions with premedication or a slower infusion rate, those with positive skin test results, and patients who developed anaphylaxis were given enzyme replacement therapy with desensitization.

CONCLUSIONS

HSR may develop during enzyme replacement therapy, which are vital in lysosomal storage diseases, and discontinuation of enzyme replacement therapy is a significant loss for patients with metabolic disorders. These reactions can be treated with premedication and long-term infusions, but some patients may require desensitization protocols for continued treatment.

TFEB agonist clomiphene citrate activates the autophagy-lysosomal pathway and ameliorates Alzheimer's disease symptoms in mice

Autophagy is a conserved eukaryotic cellular clearance and recycling process through the lysosome-mediated degradation of damaged organelles and protein aggregates to maintain homeostasis. Impairment of the autophagy-lysosomal pathway is implicated in the pathogenesis of Alzheimer's disease (AD). Transcription factor EB (TFEB) is a master regulator of autophagy and lysosomal biogenesis. Therefore, activating TFEB and autophagy provides a novel strategy for AD treatment. We previously described that clomiphene citrate (CC) promotes nuclear translocation of TFEB and increases autophagy and lysosomal biogenesis. In this study, 7- and 3-month-old APP/PS1 mice were treated with TFEB agonist CC and assessed. The behavioral tests were performed using Morris water maze and open field test. Additional changes in amyloid-β pathology, autophagy, and inflammatory response were determined. We found that CC activated TFEB and the autophagy-lysosomal pathway in neuronal cells. Moreover, using mouse model of Alzheimer's disease, CC treatment promoted clearance of amyloid-β plaques and ameliorated cognitive function in both 7- and 3-month-old APP/PS1 mice. The CC-induced activation of TFEB occurs by promoting acetylation of TFEB for nuclear translocation. These findings provide a molecular mechanism for the TFEB-mediated activation of the autophagy-lysosome pathway by CC, which has the potential to be repurposed and applied in the treatment or prevention of AD.

The neurotrophic factor MANF regulates autophagy and lysosome function to promote proteostasis in Caenorhabditis elegans

The conserved mesencephalic astrocyte-derived neurotrophic factor (MANF) is known for protecting dopaminergic neurons and functioning in various other tissues. Previously, we showed that Caenorhabditis elegans manf-1 null mutants exhibit defects such as increased endoplasmic reticulum (ER) stress, dopaminergic neurodegeneration, and abnormal protein aggregation. These findings suggest an essential role for MANF in cellular processes. However, the mechanisms by which intracellular and extracellular MANF regulate broader cellular functions remain unclear. We report a unique mechanism of action for MANF-1 that involves the transcription factor HLH-30/TFEB-mediated signaling to regulate autophagy and lysosomal function. Multiple transgenic strains overexpressing MANF-1 showed extended lifespan of animals, reduced protein aggregation, and improved neuronal survival. Using fluorescently tagged MANF-1, we observed tissue-specific localization of the protein, which was dependent on the ER retention signal. Further subcellular analysis showed that MANF-1 localizes within cells to the lysosomes and utilizes the endosomal pathway. Consistent with the lysosomal localization, our transcriptomic study of MANF-1 and analyses of autophagy regulators demonstrated that MANF-1 promotes proteostasis by regulating autophagic flux and lysosomal activity. Collectively, our findings establish MANF as a critical regulator of stress response, proteostasis, and aging.

An Acid-Activatable Fluorescent Probe for Sulfur Dioxide in Traditional Chinese Medicines and Living Cells

Excessive sulfur dioxide (SO₂) disturbs physiology of lysosomes causing diseases and threatening human health. A fluorescent probe has been regarded as one of the most attractive approaches, which is compatible with living cells and possesses high sensitivity. However, most of fluorescent probes' reaction sites are activated before they reach the destination. In this work, an acid-activatable fluorescent probe PT1 was synthesized, characterized, and used for SO2 detection. The introduction of oxazolines in PT1 enables the intelligent response of probe to release the activation stie for SO2 derivatives through Michael addition upon exposure to acid. In vitro studies showed a remarkable selectivity of PT1 to SO₂ derivatives than other biothiols with a limit of detection as low as 62 nM. By using this acidic pH-controlled fluorescence responsiveness to SO₂, precise spatiotemporal identification of lysosomal SO2 fluctuations has been successfully performed. Furthermore, probe PT1 can be applied for monitoring SO₂ derivatives in traditional Chinese medicines.

Peptide-coated DNA nanostructures as a platform for control of lysosomal function in cells

DNA nanotechnology is a rapidly growing field that provides exciting tools for biomedical applications. Targeting lysosomal functions with nanomaterials, such as DNA nanostructures (DNs), represents a rational and systematic way to control cell functionality. Here we present a versatile DNA nanostructure-based platform that can modulate a number of cellular functions depending on the concentration and surface decoration of the nanostructure. Utilizing different peptides for surface functionalization of DNs, we were able to rationally modulate lysosomal activity, which in turn translated into the control of cellular function, ranging from changes in cell morphology to modulation of immune signaling and cell death. Low concentrations of decalysine peptide-coated DNs induced lysosomal acidification, altering the metabolic activity of susceptible cells. In contrast, DNs coated with an aurein-bearing peptide promoted lysosomal alkalization, triggering STING activation. High concentrations of decalysine peptide-coated DNs caused lysosomal swelling, loss of cell-cell contacts, and morphological changes without inducing cell death. Conversely, high concentrations of aurein-coated DNs led to lysosomal rupture and mitochondrial damage, resulting in significant cytotoxicity. Our study holds promise for the rational design of a new generation of versatile DNA-based nanoplatforms that can be used in various biomedical applications, like the development of combinatorial anti-cancer platforms, efficient systems for endolysosomal escape, and nanoplatforms modulating lysosomal pH.

Black phosphorus nanosheets induce autophagy dysfunction by a size- and surface modification-related impairment of lysosomes in macrophages

The widespread application of black phosphorus nanosheets (BPNSs) raises concerns about their potential impact on human health. Although that the autophagy-inducing properties of BPNSs in cancer cells are documented, their effects on macrophages-key components of the immune system and the mechanisms involved remain obscure, especially in terms of the influences of BPNS the size and surface modifications on the autophagic process. This study investigated the effects of bare BPNSs and PEGylated BPNSs (BP-PEG) on macrophage autophagy and its underlying mechanisms by comprehensive biochemical analyses. The results indicated that both BPNSs and BP-PEG are internalized by RAW264.7 cells through phagocytosis and caveolin-dependent endocytosis, leading to lysosomal accumulation. The internalized BPNSs induced mitochondrial dysfunction, which subsequently elevated the NAD+/NADH ratio and activated the SIRT-1 pathway, initiating autophagy. However, BPNSs disrupted the autophagic flux by impairing autolysosome formation, leading to apoptosis in a size-dependent manner. In contrast, BP-PEG preserved lysosomal integrity, maintaining autophagic activity and cell viability. These findings deepen our understanding of the influence of nanosheet size and surface modifications on macrophage autophagy, contributing to the formulation of regulatory guidelines to minimize the potential adverse effects and health risks associated with BPNS utilization in various applications.

Biomineralization Synthesis of HoMn Nanoparticles for Ultrahigh-Field-Tailored and T1-T2 Dual-Mode MRI-Guided Cancer Theranostics

Ultrahigh field magnetic resonance imaging (UHF-MRI) (≥7 T) can dramatically boost image resolution and signal-to-noise ratio, which have distinct advantages in multifunctional imaging. However, their research and application are currently limited by the absence of high-field contrast agents (CAs) and the low sensitivity and accuracy of T1/T2 single-modality CAs. Therefore, the development of T1-T2 dual-mode CAs that respond to UHF-MRI and nanoformulations with therapeutic sensitization can bring ideas for the integrated application of precise and synchronous tumor theranostics. Herein, we present a biomimetic mineralization strategy for synthesizing holmium/manganese oxide-bovine serum albumin-photosensitizer chlorin e6 nanohybrids. The hybrid nanoparticles exhibited better tumor accumulation, a suitable time imaging window, and excellent pH-response T1-T2 dual-mode UHF-MRI performance. The antitumor effect comes from the amelioration of the hypoxic tumor microenvironment to promote the synergistic effect of photodynamic therapy and radiotherapy, along with negligible acute toxicity. Undoubtedly, this work not only provides a different perspective for developing multifunctional nanotherapeutics but also promotes the potential clinical exploitation and translation of UHF CAs.

Dynamic Chemistry of DNA-Based Nanoassemblies in Living Cells

ConspectusIn recent years, the controlled assembly/disassembly of exogenous chemical components inside cells has become an emerging approach to regulating cell functions. However, the construction of dynamic material chemistry systems in living cells always remains highly challenging due to the complicated intracellular microenvironment. Nucleic acid is a category of biological components that can achieve efficient molecular assembly via specific base-pairing and perform biological functions in the intracellular microenvironment. Deoxyribonucleic acid (DNA) molecules exhibit the superior performance of intracellular assembly, including sequence programmability, molecule recognition ability, and nanostructure predictability, as well as the unique biological functions that traditional synthetic polymers do not carry, showing great superiority in the construction of dynamic material chemistry systems. Moreover, the technologies of DNA synthesis are relatively mature, and the conjugation of DNA with functional small molecules can be achieved through established chemical synthesis methods, facilitating the construction of DNA-based dynamic materials with more functions. In addition, a few specific DNA molecules have been proven to show responsiveness toward different stimuli, functioning as dynamic modules.In this Account, we summarize our recent work in dynamic chemistry of DNA-based nanoassemblies in living cells from the perspective of stimulus types including enzyme, H+, glutathione (GSH), adenosine triphosphate (ATP), and light. Upon the specific stimuli, DNA-based nanoassemblies undergo precise assembly in living cells, executing disassembly or aggregation, which consequently affects the functions and behaviors of living cells. In the first part, we describe the interactions between DNA-based nanoassemblies and intracellular enzymes, namely the enzymatic cleavage of intracellular enzymes on the DNA or RNA sequences. In the second part, we summarize the effects of H+ in lysosomes on DNA-based nanoassemblies, including the formation of a tetraplex i-motif structure and the decomposition of acid-degradable polymeric coating. In the third part, we discuss the mechanism of GSH responsiveness of DNA-based nanoassemblies, including the breaking of disulfide bonds and reduction-responsive nanoparticles. In the fourth part, we describe the ATP-mediated conformational transition for the specific release of functional RNA sequences. In the fifth part, we demonstrate the light-mediated spatiotemporally dynamic chemistry of DNA-based nanoassemblies. In summary, based on the achievements of our group in the study of dynamic chemistry of DNA-based nanoassemblies, the assembly, disassembly, and reassembly in living cells are well-controlled, the regulation of cellular functions are explored, and the new strategies for cancer therapeutics are demonstrated. We envision that our work on the dynamic chemistry of DNA-based nanoassembly is a new paradigm for constructing dynamic material chemistry systems inside living cells, and will facilitate the development of precision medicine.

Lysosomal physiology and pancreatic lysosomal stress in diabetes mellitus

Endocrine and exocrine functions of the pancreas control nutritional absorption, utilisation and systemic metabolic homeostasis. Under basal conditions, the lysosome is pivotal in regulating intracellular organelles and metabolite turnover. In response to acute or chronic stress, the lysosome senses metabolic flux and inflammatory challenges, thereby initiating the adaptive programme to re-establish cellular homeostasis. A growing body of evidence has demonstrated the pathophysiological relevance of the lysosomal stress response in metabolic diseases in diverse sets of tissues/organs, such as the liver and the heart. In this review, we discuss the pathological relevance of pancreatic lysosome stress in diabetes mellitus. We begin by summarising lysosomal biology, followed by exploring the immune and metabolic functions of lysosomes and finally discussing the interplay between lysosomal stress and the pathogenesis of pancreatic diseases. Ultimately, our review aims to enhance our understanding of lysosomal stress in disease pathogenesis, which could potentially lead to the discovery of innovative treatment methods for these conditions.

A lysosomal-targeted and viscosity-ultrasensitive near-infrared fluorescent probe for sensing viscosity in cells and a diabetic mice model

Diabetes, as a metabolic disorder, has been implicated in organ dysfunction, often correlated with aberrant changes in viscosity. Lysosomal viscosity serves as an indicator of the lysosome's condition and activity, as it always varies synchronously with the change of lysosome's positioning, structure, and internal constituents. Diabetes, a condition within the metabolic disease category, has the potential to disrupt organ function due to irregular changes in viscosity. Therefore, early and precise diagnosis of diabetes is crucial for the prevention and management of diabetic conditions. Understanding the correlation between viscosity variations and lysosomal changes in vivo is vitally important for researching associated diseases. In this study, we developed Lyso-V, a near-infrared (NIR) fluorescent probe targeting lysosomes, with ultrasensitivity to viscosity changes. This probe, designed with a donor-π-bridge-acceptor (D-π-A) structure, exhibits a significant increase in NIR fluorescence intensity (approximately 690 times) when responding to viscosity, due to a twisted intramolecular charge transfer (TICT) mechanism. Furthermore, the probe designed specifically for lysosomes, enables the detection of changes in lysosomal viscosity as well as autophagy processes. Notably, through the application of this probe, we have detected an increased viscosity within the pathological model of the diabetic mouse. Moreover, Lyso-V was employed to measure the viscosity in diabetic mice. Owing to the multifaceted nature of the Lyso-V probe, it is anticipated to act as a practical and potent resource for deepening our understanding of the pathophysiological aspects of diabetes and aiding in its early detection.

A Lysosome-Targeting hNEU1 Inhibitor Treats Myocardial Infarction: A Potential Therapeutic Breakthrough

The overexpression of NEU1 has recently been certified as being associated with myocardial infarction. However, the pursuit of an efficacious human NEU1 (hNEU1) inhibitor remains challenging, and viral NEU1 (viNEU1) inhibitor drugs are significantly weaker in terms of hNEU1 inhibition. Recognizing that hNEU1 is located within the lysosome, we designed a series of lysosome-targeting compounds, derived from oseltamivir, aimed at hNEU1 inhibition. Among these compounds, OsMo exhibits the most potent activity. Our findings reveal that OsMo accumulates within lysosomes and releases its pharmacophore via enzymatic catalysis. OsMo enhances hNEU1 inhibition by accumulating pharmacophores at the target site. OsMo exhibits improved regulation of abnormal autophagy during myocardial injury, demonstrating superior efficacy in treating myocardial infarction in vivo. Furthermore, OsMo exhibits acceptable pharmacokinetic parameters. Importantly, the development of molecules with lysosome-targeting abilities represents a promising avenue for addressing myocardial injuries linked to hNEU1 overexpression.

A Screen of Plant-Based Natural Products Revealed That Quercetin Prevents Pyroglutamylated Amyloid-β (Aβ3(pE)-42) Uptake in Astrocytes As Well As Resulting Astrogliosis and Synaptic Dysfunction

Two connected histopathological hallmarks of Alzheimer's disease (AD) are chronic neuroinflammation and synaptic dysfunction. The accumulation of the most prevalent posttranslationally modified form of Aβ1-42, pyroglutamylated amyloid-β (Aβ3(pE)-42) in astrocytes is directly linked to glial activation and the release of proinflammatory cytokines that in turn contribute to early synaptic dysfunction in AD. At present, the mechanisms of Aβ3(pE)-42 uptake to astrocytes are unknown and pharmacological interventions that interfere with this process are not available. Here we developed a simple screening assay to identify substances from a plant extract library that prevent astroglial Aβ3(pE)-42 uptake. We first show that this approach yields valid and reproducible results. Second, we show endocytosis of Aβ3(pE)-42 oligomers by astrocytes and that quercetin, a plant flavonol, is effective to specifically block astrocytic buildup of oligomeric Aβ3(pE)-42. Importantly, quercetin does not induce a general impairment of endocytosis. However, it efficiently protects against early synaptic dysfunction following exogenous Aβ3(pE)-42 application.

Lysosomal Proteases and Their Inhibitors

The discovery of the lysosome, a major cytoplasmic organelle, represents a breakthrough in the understanding of intracellular protein degradation processes-proteolysis [...].