Skeletal muscle dysfunction is a common extrapulmonary comorbidity of chronic obstructive pulmonary disease (COPD) and is associated with decreased quality-of-life and survival in patients. The autophagy lysosome pathway is one of the proteolytic systems that significantly affect skeletal muscle structure and function. Intriguingly, both promoting and inhibiting autophagy have been observed to improve COPD skeletal muscle dysfunction, yet the mechanism is unclear. This paper first reviewed the effects of macroautophagy and mitophagy on the structure and function of skeletal muscle in COPD, and then explored the mechanism of autophagy mediating the dysfunction of skeletal muscle in COPD. The results showed that macroautophagy- and mitophagy-related proteins were significantly increased in COPD skeletal muscle. Promoting macroautophagy in COPD improves myogenesis and replication capacity of muscle satellite cells, while inhibiting macroautophagy in COPD myotubes increases their diameters. Mitophagy helps to maintain mitochondrial homeostasis by removing impaired mitochondria in COPD. Autophagy is a promising target for improving COPD skeletal muscle dysfunction, and further research should be conducted to elucidate the specific mechanisms by which autophagy mediates COPD skeletal muscle dysfunction, with the aim of enhancing our understanding in this field.
Pulmonary Disease, Chronic Obstructive/physiopathology* ; Autophagy/physiology* ; Humans ; Muscle, Skeletal/pathology* ; Mitophagy ; Animals ; Mitochondria/metabolism* ; Lysosomes

The dysfunction of the lysosome and autophagy-lysosome system serves as a driving force for neurodegenerative diseases, metabolic disorders, inflammatory conditions, and other related diseases, closely influencing their onset and progression. Therefore, restoring the function of the lysosome or autophagy-lysosome system has become an increasingly crucial therapeutic strategy in disease management. In this review, we will introduce the lysosomal biogenesis, structure, and function, as well as the biological process of the autophagy-lysosome system. Various diseases closely associated with lysosomal/autophagic dysfunction are also reviewed, emphasizing the significance of targeting the function of the lysosome or autophagy-lysosome system in disease treatment. Finally, we focus on engineered nanomaterials that have the capabilities to restore the function of the lysosome or autophagy-lysosome system, and summarize different strategies and methods for achieving this goal. This review aims to elucidate the latest progress in the field of nanomedicine for lysosomal/autophagic defect-related diseases and inspire the development of innovative and clinically valuable nanomedicines.
Humans ; Lysosomes/physiology* ; Autophagy/physiology* ; Nanomedicine/methods* ; Neurodegenerative Diseases/therapy* ; Animals ; Nanostructures ; Lysosomal Storage Diseases/therapy*

OBJECTIVE: To identify prognostic genes associated with lysosome-dependent cell death (LDCD) in patients with gastric cancer (GC). METHODS: Differentially expressed genes (DEGs) were identified using The Cancer Genome Atlas - Stomach Adenocarcinoma. Weighted gene co-expression network analysis was performed to identify the key module genes associated with LDCD score. Candidate genes were identified by DEGs and key module genes. Univariate Cox regression analysis, and least absolute shrinkage and selection operator regression and multivariate Cox regression analyses were performed for the selection of prognostic genes, and risk module was established. Subsequently, key cells were identified in the single-cell dataset (GSE183904), and prognostic gene expression was analyzed. Cell proliferation and migration were assessed using the Cell Counting Kit-8 assay and the wound healing assay. RESULTS: A total of 4,465 DEGs, 95 candidate genes, and 4 prognostic genes, including C19orf59, BATF2, TNFAIP2, and TNFSF18, were identified in the analysis. Receiver operating characteristic curves indicated the excellent predictive power of the risk model. Three key cell types (B cells, chief cells, and endothelial/pericyte cells) were identified in the GSE183904 dataset. C19orf59 and TNFAIP2 exhibited predominant expression in macrophage species, whereas TNFAIP2 evolved over time in endothelial/pericyte cells and chief cells. Functional experiments confirmed that interfering with C19orf59 inhibited proliferation and migration in GC cells. CONCLUSION C19orf59, BATF2, TNFAIP2, and TNFSF18 are prognostic genes associated with LDCD in GC. Furthermore, the risk model established in this study showed robust predictive power.
Stomach Neoplasms/pathology* ; Humans ; Prognosis ; Lysosomes/physiology* ; RNA-Seq ; Cell Death ; Single-Cell Analysis ; Gene Expression Regulation, Neoplastic ; Cell Proliferation ; Single-Cell Gene Expression Analysis

We have previously reported that Cystatin C (CysC) is a pivotal mediator in the neuroprotection induced by hyperbaric oxygen (HBO) preconditioning; however, the underlying mechanism and how CysC changes after stroke are not clear. In the present study, we demonstrated that CysC expression was elevated as early as 3 h after reperfusion, and this was further enhanced by HBO preconditioning. Concurrently, LC3-II and Beclin-1, two positive-markers for autophagy induction, exhibited increases similar to CysC, while knockdown of CysC blocked these elevations. As a marker of autophagy inhibition, p62 was downregulated by HBO preconditioning and this was blocked by CysC knockdown. Besides, the beneficial effects of preserving lysosomal membrane integrity and enhancing autolysosome formation induced by HBO preconditioning were abolished in CysC rats. Furthermore, we demonstrated that exogenous CysC reduced the neurological deficits and infarct volume after brain ischemic injury, while 3-methyladenine partially reversed this neuroprotection. In the present study, we showed that CysC is biochemically and morphologically essential for promoting autophagic flux, and highlighted the translational potential of HBO preconditioning and CysC for stroke treatment.
Animals ; Autophagy ; physiology ; Beclin-1 ; metabolism ; Brain ; metabolism ; pathology ; Brain Ischemia ; metabolism ; pathology ; therapy ; Cystatin C ; genetics ; metabolism ; Disease Models, Animal ; Gene Expression ; Gene Knockdown Techniques ; Hyperbaric Oxygenation ; Lysosomes ; metabolism ; pathology ; Male ; Microtubule-Associated Proteins ; metabolism ; Neurons ; metabolism ; pathology ; Neuroprotection ; physiology ; Oxygen ; therapeutic use ; Random Allocation ; Rats, Sprague-Dawley ; Rats, Transgenic ; Reperfusion Injury ; metabolism ; pathology ; therapy

The clinical treatment of joint contracture due to immobilization remains difficult. The pathological changes of muscle tissue caused by immobilization-induced joint contracture include disuse skeletal muscle atrophy and skeletal muscle tissue fibrosis. The proteolytic pathways involved in disuse muscle atrophy include the ubiquitin-proteasome-dependent pathway, caspase system pathway, matrix metalloproteinase pathway, Ca-dependent pathway and autophagy-lysosomal pathway. The important biological processes involved in skeletal muscle fibrosis include intermuscular connective tissue thickening caused by transforming growth factor-β1 and an anaerobic environment within the skeletal muscle leading to the induction of hypoxia-inducible factor-1α. This article reviews the progress made in understanding the pathological processes involved in immobilization-induced muscle contracture and the currently available treatments. Understanding the mechanisms involved in immobilization-induced contracture of muscle tissue should facilitate the development of more effective treatment measures for the different mechanisms in the future.
Atrophy ; Autophagy ; Calcium ; metabolism ; Caspases ; metabolism ; Connective Tissue ; metabolism ; pathology ; Contracture ; etiology ; metabolism ; pathology ; therapy ; Fibrosis ; Humans ; Immobilization ; adverse effects ; Joints ; Lysosomes ; metabolism ; Matrix Metalloproteinases ; metabolism ; Muscle, Skeletal ; metabolism ; pathology ; Proteasome Endopeptidase Complex ; metabolism ; Proteolysis ; Signal Transduction ; physiology ; Transforming Growth Factor beta1 ; metabolism ; Ubiquitin ; metabolism

Alterations of the autophagy-lysosomal pathway (ALP) and autophagy have been involved in lung ischemia-reperfusion (I/R) injury. However, dynamic imaging of ALP function under lung I/R injury particularly is not fully understood. Here we depicted the live-cell fluorescence imaging of autophagosome to monitor ALP activation and autophagy function. The pAsRed2-N1-LC3 vectors were transfected into CRL-2192 NR8383 (an alveolar macrophage cell line) and CCL149 (an alveolar epithelial cell line) successfully. 0-h, 2-h, 4-h, and 6-h hypoxia/0-h, 2-h, 4-h, and 6-h reoxygenation were then induced with an ALP inhibitor (3-MA) or activator (rapamycin) in the culture of transfected cells separately. ALP activation was conformed by up-regulating AMPK and beclin1 expression. Apoptosis was not obvious in 2-h hypoxia/2-h reoxygenation. pAsRed2-N1-LC3 CCL149 and pAsRed2-N1-LC3 NR8383 cells revealed gradually enhanced AsRed2 from 2-h to 6-h hypoxia/reoxygenation. AsRed2 varied sensitively to 3-MA and rapamycin interventions during 2-h hypoxia/reoxygenation. Our data provides a simple method of autophagosome imaging to monitor ALP activation and autophagy function in lung I/R injury.
Animals ; Autophagy ; Base Sequence ; DNA Primers ; Hypoxia ; physiopathology ; In Vitro Techniques ; Lung ; physiopathology ; Lysosomes ; physiology ; Oxygen Inhalation Therapy ; Rats ; Real-Time Polymerase Chain Reaction

The fungus Trichophyton schoenleinii (T. schoenleinii) is the causative agent of Trichophytosis and Tinea favosa of the scalp in certain regions of Eurasia and Africa. Human innate immune system plays an important role in combating with various pathogens including fungi. The inflammasome is one of the most critical arms of host innate immunity, which is a protein complex controlling maturation of IL-1β. To clarify whether T. schoenleinii is able to activate the inflammasome, we analyzed human monocytic cell line THP-1 for IL-1β production upon infection with T. schoenleinii strain isolated from Tinea favosa patients, and rapid IL-1β secretion from THP-1 cells was observed. Moreover, applying competitive inhibitors and gene specific silencing with shRNA, we found that T. schoenleinii induced IL-1β secretion, ASC pyroptosome formation as well as caspase-1 activation were all dependent on NLRP3. Cathepsin B activity, ROS production and K⁺ efflux were required for the inflammasome activation by T. schoenleinii. Our data thus reveal that the NLRP3 inflammasome plays an important role in host defense against T. schoenleinii, and suggest that manipulating NLRP3 signaling can be a novel approach for control of diseases caused by T. schoenleinii infection.
Animals ; Bone Marrow Cells ; cytology ; Carrier Proteins ; metabolism ; Caspase 1 ; metabolism ; Cell Line ; Dendritic Cells ; cytology ; metabolism ; microbiology ; Enzyme Activation ; Hot Temperature ; Humans ; Inflammasomes ; metabolism ; Interleukin-1beta ; biosynthesis ; metabolism ; Lysosomes ; metabolism ; Mice ; Monocytes ; cytology ; metabolism ; microbiology ; NLR Family, Pyrin Domain-Containing 3 Protein ; Potassium ; metabolism ; Reactive Oxygen Species ; metabolism ; Signal Transduction ; Trichophyton ; physiology

Autophagy is an intracellular degradation system that delivers cytoplasmic contents to the lysosome for degradation. It is a "self-eating" process and plays a "house-cleaner" role in cells. The complex process consists of several sequential steps-induction, autophagosome formation, fusion of lysosome and autophagosome, degradation, efflux transportation of degradation products, and autophagic lysosome reformation. In this review, the cellular and molecular regulations of late stage of autophagy, including cellular events after fusion step, are summarized.
Animals ; Autophagy ; physiology ; Humans ; Lysosomes ; metabolism ; physiology

OBJECTIVE: To determine the distribution and influence of lysosomal neuraminidase (Neul), protective protein/cathepsin A (PPCA) and beta-galactosidase (beta-gal) in the inner ear of the mouse, and to observe their auditory alterations in enzyme deficiency. METHODS: Six wild type (2 months postnatal) (Neu1+/+, PPCA+/+ and beta-gal+/+) mice were used, and Neu1, PPCA and beta-gal homozygous (Neu1-/-, PPCA-/- and beta-gal-/-) mice at the same age used as control in this experiment. The auditory thresholds were examined through the auditory brainstem responses (ABR) to click, which tone pips were 8, 16, and 32 kHz. The mice were intracardically perfused with 4% paraformaldehyde. The bulla were further fixed in 4% paraformaldehyde, processed and sectioned with paraffin embedded method. Immunohistochemistry was used to determine the cellular localizations of Neu1, PP-CA, and beta gal in the inner ear. RESULTS: There was a similar distributive pattern of Neu1, PPCA and betagal in the inner ear. Neu1 intense staining was observed in the cochlear spiral ganglion cells, spiral limbus, spiral ligament, vestibular ganglion cells, cristae, maculae hair cells, and weak staining in inner hair cells, outer hair cells, supplying cells of the organ of Corti and stria vascularis. The intense staining of PPCA and beta-gal were observed in the spiral ganglion and vestibular ganglion cells, and weak staining in the spiral limbus, spiral ligament, stria vascularis and organ of Corti. The inner ear exhibited no staining when Neul, PPCA and beta-gal were deficient, respectively. A positive staining of PPCA and beta-gal was presented in Neu1-/- mice, and as well as Neu1 and PPCA in beta-gal-/- mice. However, the staining of Neu1 was not presented, and only very weak staining of beta-gal in PPCA-/- mice. The auditory thresholds of Neul, PPCA, and beta-gal mice were elevated for 60-69 dB, 40-48 dB, and 7-10 dB above those of wildtype littermates, respectively. CONCLUSION Neu1 PPCA and beta-gal are distributed in the inner ear of mouse, and the three enzymes also form a lysosomal multi-enzyme complex in the inner ear. The respective enzyme deficiencies can induce the hearing the loss of different levels.
Animals ; Auditory Threshold ; Cathepsin A ; genetics ; metabolism ; Ear, Inner ; enzymology ; Evoked Potentials, Auditory, Brain Stem ; physiology ; Hearing Loss, Sensorineural ; enzymology ; genetics ; Lysosomes ; enzymology ; Mice ; Mice, Knockout ; Neuraminidase ; genetics ; metabolism ; beta-Galactosidase ; genetics ; metabolism

DNA vaccination that can induce both cellular and humoral immune response has become an attractive immunization strategy against cancer and infectious disease. Elucidation of the precise mechanisms of immune priming will be important in the development of effective DNA vaccines. In this review, we illustrate possible mechanisms in priming cytotoxic T cell response involving the intracellular degradation, processing and presentation of encoded antigen. We also discuss the roles of costimulatory molecules expressed on antigen-presenting cells (APCs) in inducing optimal CTL activity. Hence, a rational strategy for increasing DNA potency would be to facilitate these pathways. Additionally, we focus on recent strategies including rapid degradation of ubiquitin-antigen fusion proteins, direct targeting to APCs for increased DNA uptake, direct routing an antigen into the MHC class I and II processing and presentation pathways, and increasing the immunogenicity of encoded antigen. All of these approaches have resulted in increased potency of DNA vaccines.
Animals ; Antigen Presentation ; Antigen-Presenting Cells ; immunology ; Lysosomes ; immunology ; Mice ; T-Lymphocytes, Cytotoxic ; immunology ; Ubiquitin ; physiology ; Vaccines, DNA ; genetics ; immunology