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Biomedicine & Pharmacotherapy =... May 2024Osteoarthritis (OA) is a chronic joint disease, characterized by degenerative destruction of articular cartilage. Chondrocytes, the unique cell type in cartilage,...
Osteoarthritis (OA) is a chronic joint disease, characterized by degenerative destruction of articular cartilage. Chondrocytes, the unique cell type in cartilage, mediate the metabolism of extracellular matrix (ECM), which is mainly constituted by aggrecan and type II collagen. A disintegrin and metalloproteinase with thrombospondin 5 (ADAMTS5) is an aggrecanase responsible for the degradation of aggrecan in OA cartilage. CCAAT/enhancer binding protein β (C/EBPβ), a transcription factor in the C/EBP family, has been reported to mediate the expression of ADAMTS5. Our previous study showed that 5,7,3',4'-tetramethoxyflavone (TMF) could activate the Sirt1/FOXO3a signaling in OA chondrocytes. However, whether TMF protected against ECM degradation by down-regulating C/EBPβ expression was unknown. In this study, we found that aggrecan expression was down-regulated, and ADAMTS5 expression was up-regulated. Knockdown of C/EBPβ could up-regulate aggrecan expression and down-regulate ADAMTS5 expression in IL-1β-treated C28/I2 cells. TMF could compromise the effects of C/EBPβ on OA chondrocytes by activating the Sirt1/FOXO3a signaling. Conclusively, TMF exhibited protective activity against ECM degradation by mediating the Sirt1/FOXO3a/C/EBPβ pathway in OA chondrocytes.
Topics: ADAMTS5 Protein; Humans; Extracellular Matrix; Signal Transduction; Chondrocytes; Osteoarthritis; CCAAT-Enhancer-Binding Protein-beta; Male; Sirtuin 1; Aggrecans; Flavonoids; Interleukin-1beta; Cell Line; Forkhead Box Protein O3; Cartilage, Articular; Middle Aged; Aged; Down-Regulation
PubMed: 38554527
DOI: 10.1016/j.biopha.2024.116501 -
Nature Communications Mar 2024Integration of extracellular signals by neurons is pivotal for brain development, plasticity, and repair. Axon guidance relies on receptor-ligand interactions...
Integration of extracellular signals by neurons is pivotal for brain development, plasticity, and repair. Axon guidance relies on receptor-ligand interactions crosstalking with extracellular matrix components. Semaphorin-5A (Sema5A) is a bifunctional guidance cue exerting attractive and inhibitory effects on neuronal growth through the interaction with heparan sulfate (HS) and chondroitin sulfate (CS) glycosaminoglycans (GAGs), respectively. Sema5A harbors seven thrombospondin type-1 repeats (TSR1-7) important for GAG binding, however the underlying molecular basis and functions in vivo remain enigmatic. Here we dissect the structural basis for Sema5A:GAG specificity and demonstrate the functional significance of this interaction in vivo. Using x-ray crystallography, we reveal a dimeric fold variation for TSR4 that accommodates GAG interactions. TSR4 co-crystal structures identify binding residues validated by site-directed mutagenesis. In vitro and cell-based assays uncover specific GAG epitopes necessary for TSR association. We demonstrate that HS-GAG binding is preferred over CS-GAG and mediates Sema5A oligomerization. In vivo, Sema5A:GAG interactions are necessary for Sema5A function and regulate Plexin-A2 dependent dentate progenitor cell migration. Our study rationalizes Sema5A associated developmental and neurological disorders and provides mechanistic insights into how multifaceted guidance functions of a single transmembrane cue are regulated by proteoglycans.
Topics: Glycosaminoglycans; Proteoglycans; Heparitin Sulfate; Cell Movement; Semaphorins
PubMed: 38548715
DOI: 10.1038/s41467-024-46725-7 -
Pharmaceuticals (Basel, Switzerland) Feb 2024Developing effective anti-fibrotic therapies for heart diseases holds the potential to address unmet needs in several cardiac conditions, including heart failure with... (Review)
Review
Developing effective anti-fibrotic therapies for heart diseases holds the potential to address unmet needs in several cardiac conditions, including heart failure with preserved ejection fraction, hypertrophic cardiomyopathy, and cardiotoxicity induced by cancer therapy. The inhibition of the primary fibrotic regulator, transforming growth factor (TGF) β, represents an efficient strategy for mitigating fibrosis in preclinical models. However, translating these findings into clinical benefits faces challenges due to potential adverse effects stemming from TGF-β's physiological actions in inflammation and tissue homeostasis. Various strategies exist for inhibiting TGF-β, each associated with a distinct risk of adverse effects. Targeting TGF-β directly or through its signaling pathway proves efficient in reducing fibrosis. However, direct TGF-β blockade may lead to uncontrolled inflammation, especially following myocardial infarction, while interference with the signaling pathway may compromise structural integrity, resulting in issues like insufficient wound healing or ventricular dilatation. Influencing TGF-β activity through interacting signaling pathways, for instance by inhibitors of the renin-angiotensin-aldosterone-system, is insufficiently potent in reducing fibrosis. Targeting activators of latent TGF-β, including ADAMTS enzymes, thrombospondin, and integrins, emerges as a potentially safer strategy to reduce TGF-β-induced fibrosis but it requires the identification of appropriate targets. Encouragement is drawn from promising agents developed for fibrosis in other organs, fueling hope for similar breakthroughs in treating cardiac fibrosis. Such advances depend on overcoming obstacles for the implementation of anti-fibrotic strategies in patients with heart disease, including fibrosis quantification. In this review, insights garnered from interventional and mechanistic studies, obtained through a non-systemic search spanning preclinical and clinical evidence, are summarized to pinpoint the most promising targets for further exploration and development.
PubMed: 38543053
DOI: 10.3390/ph17030267 -
Biomolecules Feb 2024Viperid snake venoms induce severe tissue damage, characterized by the direct toxic action of venom components, i.e., phospholipases A (PLAs) and metalloproteinases...
Viperid snake venoms induce severe tissue damage, characterized by the direct toxic action of venom components, i.e., phospholipases A (PLAs) and metalloproteinases (SVMPs), concomitantly with the onset of endogenous inflammatory processes, in an intricate scenario of tissue alterations. Understanding the expression of relevant genes in muscle tissue will provide valuable insights into the undergoing pathological and inflammatory processes. In this study, we have used the Nanostring technology to evaluate the patterns of gene expression in mouse skeletal muscle 1 h, 6 h, and 24 h after injection of the venoms of and , two medically relevant species in Latin America and Asia, respectively, with somewhat different clinical manifestations. The dose of venoms injected (30 µg) induced local pathological effects and inflammation in muscle tissue. We focused our analysis on genes related to extracellular matrix (ECM) metabolism, immune system, programmed cell death, and autophagy. The results revealed a complex pattern of expression of genes. Regarding ECM metabolism and regulation, up-regulated genes included proteinase inhibitor Serpine 1, thrombospondin 1, collagens 1A1 and 4A1 (at 1 h in the case of ), TIMP1, MMP-3 (at 24 h), and lysil oxidase (LOX). In contrast, collagen chains 5A3 and 5A1 were down-regulated, especially at 6 h. Transforming growth factor β (TGF-β) and several genes related to myofibroblast regulation were also up-regulated, which might be related to the development of fibrosis. Several genes related to cytokine and chemokine synthesis and regulation and NFκB signaling were also up-regulated. Our observations show a variable expression of genes associated with programmed cell death and autophagy, thus revealing a hitherto unknown role of autophagy in tissue affected by snake venoms. These results provide clues to understanding the complex pattern of gene expression in tissue affected by viperid snake venoms, which likely impacts the final pathophysiology of damaged tissue in envenomings.
Topics: Animals; Mice; Antivenins; Snake Bites; Snake Venoms; Crotalid Venoms; Muscles; Collagen
PubMed: 38540699
DOI: 10.3390/biom14030278 -
Nature Apr 2024The immune system has a critical role in orchestrating tissue healing. As a result, regenerative strategies that control immune components have proved effective. This is...
The immune system has a critical role in orchestrating tissue healing. As a result, regenerative strategies that control immune components have proved effective. This is particularly relevant when immune dysregulation that results from conditions such as diabetes or advanced age impairs tissue healing following injury. Nociceptive sensory neurons have a crucial role as immunoregulators and exert both protective and harmful effects depending on the context. However, how neuro-immune interactions affect tissue repair and regeneration following acute injury is unclear. Here we show that ablation of the Na1.8 nociceptor impairs skin wound repair and muscle regeneration after acute tissue injury. Nociceptor endings grow into injured skin and muscle tissues and signal to immune cells through the neuropeptide calcitonin gene-related peptide (CGRP) during the healing process. CGRP acts via receptor activity-modifying protein 1 (RAMP1) on neutrophils, monocytes and macrophages to inhibit recruitment, accelerate death, enhance efferocytosis and polarize macrophages towards a pro-repair phenotype. The effects of CGRP on neutrophils and macrophages are mediated via thrombospondin-1 release and its subsequent autocrine and/or paracrine effects. In mice without nociceptors and diabetic mice with peripheral neuropathies, delivery of an engineered version of CGRP accelerated wound healing and promoted muscle regeneration. Harnessing neuro-immune interactions has potential to treat non-healing tissues in which dysregulated neuro-immune interactions impair tissue healing.
Topics: Animals; Mice; Autocrine Communication; Calcitonin Gene-Related Peptide; Diabetes Mellitus, Experimental; Efferocytosis; Macrophages; Monocytes; Muscle, Skeletal; NAV1.8 Voltage-Gated Sodium Channel; Neutrophils; Nociceptors; Paracrine Communication; Peripheral Nervous System Diseases; Receptor Activity-Modifying Protein 1; Regeneration; Skin; Thrombospondin 1; Wound Healing; Humans; Male; Female
PubMed: 38538784
DOI: 10.1038/s41586-024-07237-y -
Memorias Do Instituto Oswaldo Cruz 2024Malaria is an infectious disease caused by protozoan parasites belonging to the genus Plasmodium. Human-to-human transmission depends on a mosquito vector; thus, the...
BACKGROUND
Malaria is an infectious disease caused by protozoan parasites belonging to the genus Plasmodium. Human-to-human transmission depends on a mosquito vector; thus, the interruption of parasite transmission from humans to mosquitoes is an important approach in the fight against malaria. The parasite stages infectious to mosquitoes are the gametocytes, sexual stages that are ingested by the vector during a blood meal and transform into male and female gametes in the midgut. Immunity against sexual stage antigens expressed by gametocytes, gametes, and the zygote formed after fertilisation can interrupt the parasite sexual cycle in the mosquito. This transmission blocking immunity is mediated by specific antibodies ingested during the mosquito blood feed, inhibiting the parasite development in the midgut. Merozoite thrombospondin related anonymous protein (MTRAP) is a merozoite and gametocyte surface protein essential for gamete egress from erythrocytes and for parasite transmission to mosquitoes.
OBJECTIVES
Here, we evaluated the potential of the P. berghei MTRAP to elicit antibodies with the ability to inhibit gamete fertilisation in vitro.
METHODS
We expressed a soluble recombinant PbMTRAP and used it to immunise BALB/c mice. The transmission blocking activity of the anti-rPbMTRAP antibodies was tested through in vivo challenge experiments followed by in vitro conversion assays.
FINDINGS
Immunisations with the rPbMTRAP induced a strong antibody response and the antibodies recognised the native protein by Western Blot and IFA. Anti-rPbMTRAP present in the blood stream of immunised mice partially inhibited gamete conversion into ookinetes.
CONCLUSION
Our results indicate that antibodies to PbMTRAP may reduce but are not sufficient to completely block transmission.
Topics: Male; Female; Humans; Animals; Mice; Protozoan Proteins; Plasmodium berghei; Merozoites; Malaria; Culicidae
PubMed: 38537036
DOI: 10.1590/0074-02760230217 -
Cells Mar 2024Extended liver resection carries the risk of post-surgery liver failure involving thrombospondin-1-mediated aggravation of hepatic epithelial plasticity and function....
Extended liver resection carries the risk of post-surgery liver failure involving thrombospondin-1-mediated aggravation of hepatic epithelial plasticity and function. Mesenchymal stromal cells (MSCs), by interfering with thrombospondin-1 (THBS1), counteract hepatic dysfunction, though the mechanisms involved remain unknown. Herein, two-thirds partial hepatectomy in mice increased hepatic THBS1, downstream transforming growth factor-β3, and perturbation of liver tissue homeostasis. All these events were ameliorated by hepatic transfusion of human bone marrow-derived MSCs. Treatment attenuated platelet and macrophage recruitment to the liver, both major sources of THBS1. By mitigating THBS1, MSCs muted surgery-induced tissue deterioration and dysfunction, and thus supported post-hepatectomy regeneration. After liver surgery, patients displayed increased tissue THBS1, which is associated with functional impairment and may indicate a higher risk of post-surgery complications. Since liver dysfunction involving THBS1 improves with MSC treatment in various animal models, it seems feasible to also modulate THBS1 in humans to impede post-surgery acute liver failure.
Topics: Humans; Mice; Animals; Hepatectomy; Liver Regeneration; Mesenchymal Stem Cells; Liver Diseases; Thrombospondins
PubMed: 38534373
DOI: 10.3390/cells13060529 -
European Journal of Medical Research Mar 2024Intervertebral disc degeneration (IVDD) is a major cause of morbidity and disability. Our study aimed to investigate the potential of cartilage oligomeric matrix protein...
OBJECTIVE
Intervertebral disc degeneration (IVDD) is a major cause of morbidity and disability. Our study aimed to investigate the potential of cartilage oligomeric matrix protein (COMP) and ADAMTS7 (A disintegrin and metalloproteinases with thrombospondin motifs 7) as biomarkers for IVDD together with their functional relationship.
METHODS
IVD tissues and peripheral blood samples were collected from IVDD rabbit models over 1-4 weeks. Tissues and blood samples were also collected from clinical patients those were stratified into four equal groups according to Pfirrmann IVDD grading (I-V) with baseline data collected for each participant. COMP and ADAMTS7 expression were analyzed and biomarker characteristics were assessed using linear regression and receiver operating curve (ROC) analyses.
RESULTS
COMP and ADAMTS7 expression increased in tissues and serum during IVDD progression. Serum COMP (sCOMP) and serum ADAMTS7 (sADAMTS7) levels increased in a time-dependent manner following IVD damage in the rabbit model while significant positive correlations were detected between sCOMP and sADAMTS7 and Pfirrmann grade in human subjects. ROC analysis showed that combining sCOMP and sADAMTS7 assay results produced an improved diagnostic measure for IVDD compared to individual sCOMP or sADAMTS7 tests. In vitro assays conducted on human cell isolates revealed that COMP prevented extracellular matrix degradation and antagonized ADAMTS7 expression although this protective role was uncoupled under microenvironmental conditions mimicking IVDD.
CONCLUSIONS
Increases in circulating COMP and ADAMTS7 correlate with IVDD progression and may play regulatory roles. Assays for sCOMP and/or sADAMTS7 levels can discriminate between healthy subjects and IVDD patients, warranting further clinical assessment.
Topics: Animals; Humans; Rabbits; ADAMTS7 Protein; Biomarkers; Cartilage Oligomeric Matrix Protein; Intervertebral Disc; Intervertebral Disc Degeneration
PubMed: 38528617
DOI: 10.1186/s40001-024-01784-w -
Thrombosis Research May 2024
Topics: Humans; Thrombospondin 1; Endotoxins; Deamino Arginine Vasopressin; Male
PubMed: 38521738
DOI: 10.1016/j.thromres.2024.01.011 -
Frontiers in Cardiovascular Medicine 2024Cardiovascular diseases have been identified as vital factors in global morbidity and mortality in recent years. The available evidence suggests that various cytokines... (Review)
Review
Cardiovascular diseases have been identified as vital factors in global morbidity and mortality in recent years. The available evidence suggests that various cytokines and pathological proteins participate in these complicated and changeable diseases. The thrombospondin (TSP) family is a series of conserved, multidomain calcium-binding glycoproteins that cause cell-matrix and cell-cell effects via interactions with other extracellular matrix components and cell surface receptors. The TSP family has five members that can be divided into two groups (Group A and Group B) based on their different structures. TSP-1, TSP-2, and TSP-4 are the most studied proteins. Among recent studies and findings, we investigated the functions of several family members, especially TSP-5. We review the basic concepts of TSPs and summarize the relevant molecular mechanisms and cell interactions in the cardiovascular system. Targeting TSPs in CVD and other diseases has a remarkable therapeutic benefit.
PubMed: 38516004
DOI: 10.3389/fcvm.2024.1337586