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1.
Biomed J ; : 100731, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38677491

ABSTRACT

BACKGROUND: Autoimmune hepatitis (AIH) is an immune-mediated hepatic disease associated with intense complications. AIH is more common in females and needs effective drugs to treat. Guizhi Fuling Wan (GZFLW) is a traditional Chinese herbal formula used to treat various gynecologic diseases. In this study, we aim to extend the new use of GZFLW for AIH. METHODS: The tandem MS-based analysis was used to identify secondary metabolites in GZFLW. Therapeutic effects of GZFLW were tested in a concanavalin A (Con A)-induced AIH model in mice. Ethnopharmacological mechanisms underlying the antiapoptotic, antioxidant, and immunomodulatory protective effects were determined. RESULTS: Oral administration of GZFLW attenuates AIH in a Con A-induced hepatotoxic model in vivo. The tandem MS-based analysis identified 15 secondary metabolites in GZFLW. The Con A-induced AIH syndromes, including hepatic apoptosis, inflammation, reactive oxygen species accumulation, function failure, and mortality, were significantly alleviated by GZFLW in mice. Mechanistically, GZFLW restrained the caspase-dependent apoptosis, restored the antioxidant system, and decreased pro-inflammatory cytokine production in the livers of Con A-treated mice. Besides, GZFLW repressed the Con A-induced hepatic infiltration of inflammatory cells, splenic T cell activation, and splenomegaly in mice. CONCLUSIONS: Our findings demonstrate the applicable potential of GZFLW in treating AIH. It prompts further investigation of GZFLW as a treatment option for AIH and possibly other hepatic diseases.

2.
Int J Mol Sci ; 23(22)2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36430939

ABSTRACT

The intestinal epithelium forms a physical barrier assembled by intercellular junctions, preventing luminal pathogens and toxins from crossing it. The integrity of tight junctions is critical for maintaining intestinal health as the breakdown of tight junction proteins leads to various disorders. Redox reactions are closely associated with energy metabolism. Understanding the regulation of tight junctions by cellular metabolism and redox status in cells may lead to the identification of potential targets for therapeutic interventions. In vitro and in vivo models have been utilized in investigating intestinal barrier dysfunction and in particular the free-living soil nematode, Caenorhabditis elegans, may be an important alternative to mammalian models because of its convenience of culture, transparent body for microscopy, short generation time, invariant cell lineage and tractable genetics.


Subject(s)
Gastrointestinal Diseases , Tight Junctions , Animals , Tight Junctions/metabolism , Tight Junction Proteins/metabolism , Intestinal Mucosa/metabolism , Intestines , Oxidation-Reduction , Gastrointestinal Diseases/metabolism , Mammals/metabolism
3.
Int J Mol Sci ; 23(7)2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35408794

ABSTRACT

When activated by thrombin, the platelets release their granular store of factors. These thrombin-activated platelets (TAPLT) have been shown to be capable of ameliorating pro-inflammatory processes. In this study, we tested if TAPLT could also protect the endothelium against tumor-related pro-inflammatory changes that promote angiogenesis and metastasis. Using endothelial cell (EC) models in vitro, we demonstrated that TAPLT protected EC against tumor conditioned medium (TCM)-induced increases of reactive oxygen species (ROS) production, EC permeability and angiogenesis, and inhibited transendothelial migration that was critical for cancer cell extravasation and metastasis. In vivo observations of TAPLT-mediated inhibition of angiogenesis and pulmonary colonization in a BALB/c nude mouse model were consistent with the in vitro findings. Neutralization of vascular cell adhesion molecule-1 (VCAM-1) binding significantly inhibited the ability of TAPLT to interact with EC and abrogated the TAPLT-mediated protection of EC against tumor angiogenesis and metastasis. Taken together, these findings suggest that VCAM-1-mediated linkage to EC is required for TAPLT to confer protection of EC against tumor-induced permeation and angiogenesis, thereby resisting tumor extravasation and metastasis.


Subject(s)
Endothelium, Vascular , Vascular Cell Adhesion Molecule-1 , Animals , Blood Platelets/metabolism , Cell Adhesion/physiology , Cell Movement , Cells, Cultured , E-Selectin/metabolism , Endothelium, Vascular/metabolism , Mice , Thrombin/metabolism , Thrombin/pharmacology , Vascular Cell Adhesion Molecule-1/metabolism
4.
Aging (Albany NY) ; 13(10): 13474-13495, 2021 05 20.
Article in English | MEDLINE | ID: mdl-34091442

ABSTRACT

The medicinal fungus Ganoderma lucidum is used as a dietary supplement and health tonic, but whether it affects longevity remains unclear. We show here that a water extract of G. lucidum mycelium extends lifespan of the nematode Caenorhabditis elegans. The G. lucidum extract reduces the level of fibrillarin (FIB-1), a nucleolar protein that correlates inversely with longevity in various organisms. Furthermore, G. lucidum treatment increases expression of the autophagosomal protein marker LGG-1, and lifespan extension is abrogated in mutant C. elegans strains that lack atg-18, daf-16, or sir-2.1, indicating that autophagy and stress resistance pathways are required to extend lifespan. In cultured human cells, G. lucidum increases concentrations of the LGG-1 ortholog LC3 and reduces levels of phosphorylated mTOR, a known inhibitor of autophagy. Notably, low molecular weight compounds (<10 kDa) isolated from the G. lucidum water extract prolong lifespan of C. elegans and the same compounds induce autophagy in human cells. These results suggest that G. lucidum can increase longevity by inducing autophagy and stress resistance.


Subject(s)
Autophagy , Caenorhabditis elegans/cytology , Caenorhabditis elegans/physiology , Longevity/physiology , Reishi/chemistry , Animals , Caenorhabditis elegans Proteins/metabolism , Cell Line, Tumor , Humans , Signal Transduction , TOR Serine-Threonine Kinases/metabolism
5.
Ageing Res Rev ; 66: 101240, 2021 03.
Article in English | MEDLINE | ID: mdl-33347992

ABSTRACT

Caloric restriction (CR) mimetics are molecules that produce beneficial effects on health and longevity in model organisms and humans, without the challenges of maintaining a CR diet. Conventional CR mimetics such as metformin, rapamycin and spermidine activate autophagy, leading to recycling of cellular components and improvement of physiological function. We review here novel CR mimetics and anti-aging compounds, such as 4,4'-dimethoxychalcone, fungal polysaccharides, inorganic nitrate, and trientine, highlighting their possible molecular targets and mechanisms of action. The activity of these compounds can be understood within the context of hormesis, a biphasic dose response that involves beneficial effects at low or moderate doses and toxic effects at high doses. The concept of hormesis has widespread implications for the identification of CR mimetics in experimental assays, testing in clinical trials, and use in healthy humans. We also discuss the promises and limitations of CR mimetics and anti-aging molecules for delaying aging and treating chronic diseases.


Subject(s)
Aging , Caloric Restriction , Autophagy , Hormesis , Humans , Longevity
6.
Biomed J ; 44(6): 686-693, 2021 12.
Article in English | MEDLINE | ID: mdl-35166207

ABSTRACT

BACKGROUND: The formation of dental plaque and its involvement in the pathogenesis of periodontitis is a topic of intense interest given the high prevalence of periodontitis in humans. Even though calcium-based particles play an active role in both dental plaque formation and periodontitis, few publications describe the physical-chemical properties of these particles. METHODS: Saliva samples were collected from healthy volunteers. From these samples, saliva-derived particles were isolated and stained for calcium using calcein or Fluo-4. The salivary particles were also subjected to characterization by flow cytometry and immunoblotting. Internalization of calcein-labeled salivary particles by gingival epithelial cells was visualized by confocal microscopy. RESULTS: We found that calcium-based salivary particles from healthy volunteers varied greatly in size but were enriched in particles of sizes at or greater than 1.5 µm. Immunoblotting analysis of the salivary particles identified several proteins including albumin, fetuin-A, and statherin, which have been found in calcium phosphate particles from other tissues or are known to modulate calcium homeostasis in saliva. In addition, calcium particles were internalized by both gingival epithelial cells and monocyte-derived macrophages. CONCLUSION: Salivary calcium particles were enriched in the micrometer range, internalized by gingival epithelial cells, and contain albumin, fetuin-A and statherin, regulators of particle formation. These characteristics of the calcium-based salivary particles and their biological activities provide a basis for further studies to understand the molecular basis for pathogenesis of periodontitis.


Subject(s)
Calcium , Periodontitis , Calcium/analysis , Calcium/metabolism , Epithelium/metabolism , Gingiva/metabolism , Gingiva/pathology , Humans , Saliva/chemistry
7.
Microb Cell ; 7(10): 255-269, 2020 Jul 09.
Article in English | MEDLINE | ID: mdl-33015140

ABSTRACT

The nematode Caenorhabditis elegans is a useful model to study aging due to its short lifespan, ease of manipulation, and available genetic tools. Several molecules and extracts derived from plants and fungi extend the lifespan of C. elegans by modulating aging-related pathways that are conserved in more complex organisms. Modulation of aging pathways leads to activation of autophagy, mitochondrial biogenesis and expression of antioxidant and detoxifying enzymes in a manner similar to caloric restriction. Low and moderate concentrations of plant and fungal molecules usually extend lifespan, while high concentrations are detrimental, consistent with a lifespan-modulating mechanism involving hormesis. We review here molecules and extracts derived from plants and fungi that extend the lifespan of C. elegans, and explore the possibility that these natural substances may produce health benefits in humans.

8.
Med Res Rev ; 40(6): 2114-2131, 2020 11.
Article in English | MEDLINE | ID: mdl-32578904

ABSTRACT

Senescence is a state of cell cycle arrest that plays an important role in embryogenesis, wound healing and protection against cancer. Senescent cells also accumulate during aging and contribute to the development of age-related disorders and chronic diseases, such as atherosclerosis, type 2 diabetes, osteoarthritis, idiopathic pulmonary fibrosis, and liver disease. Molecules that induce apoptosis of senescent cells, such as dasatinib, quercetin, and fisetin, produce health benefits and extend lifespan in animal models. We describe here the mechanism of action of senolytics and senomorphics, many of which are derived from plants and fungi. We also discuss the possibility of using such compounds to delay aging and treat chronic diseases in humans.


Subject(s)
Cellular Senescence , Diabetes Mellitus, Type 2 , Aging , Animals , Chronic Disease , Humans , Longevity
9.
Article in English | MEDLINE | ID: mdl-31300373

ABSTRACT

OBJECTIVES: This study aimed to evaluate the clinical and histopathologic features of gingival lesions containing foreign material (GLFMs). In parallel, the composition of the foreign material and its effects in primary human gingival fibroblasts (HGFs) were investigated. STUDY DESIGN: Eighty-six GLFMs were retrieved from an oral pathology biopsy service. Clinical and microscopic data were analyzed, and the composition of the particles was identified by using energy-dispersive X-ray spectroscopy (EDX). Furthermore, HGFs were stimulated with silica (SiO2) microparticles to investigate the production of collagen type 1 (COL-1), matrix metalloproteinase 2 (MMP2), and inflammatory cytokines. RESULTS: GLFMs were most commonly found in women (60.5%) and most frequently described as white plaques. Histopathologic examination identified verrucous hyperplasia in 59% and epithelial dysplasia in 28% of the cases. EDX microanalysis revealed that Si (94%) was the most frequently detected foreign element. SiO2 microparticles induced higher COL-1 expression; higher levels of proinflammatory cytokines, such as interleukin-6 (IL-6), IL-8, and transforming growth factor-ß, and increased MMP-2 activity in HGFs. CONCLUSIONS: There was a strong association between the presence of foreign material in the gingiva and white verrucous clinical lesions. In addition, the most common element in the foreign material was Si, and our in vitro findings demonstrate the importance of silica-mediated effects on gingival fibroblasts.


Subject(s)
Gingiva , Cells, Cultured , Female , Fibroblasts , Humans , Interleukin-6 , Male , Matrix Metalloproteinase 2 , Silicon Dioxide
10.
Trends Endocrinol Metab ; 30(6): 335-346, 2019 06.
Article in English | MEDLINE | ID: mdl-31060881

ABSTRACT

Caloric restriction, intermittent fasting, and exercise activate defensive cellular responses such as autophagy, DNA repair, and the induction of antioxidant enzymes. These processes improve health and longevity by protecting cells and organs against damage, mutations, and reactive oxygen species. Consuming a diet rich in vegetables, fruits, and mushrooms can also improve health and longevity. Phytochemicals such as alkaloids, polyphenols, and terpenoids found in plants and fungi activate the same cellular processes as caloric restriction, fasting, and exercise. Many of the beneficial effects of fruits and vegetables may thus be due to activation of stress resistance pathways by phytochemicals. A better understanding of the mechanisms of action of phytochemicals may provide important insights to delay aging and prevent chronic diseases.


Subject(s)
Phytochemicals , Aging/physiology , Caloric Restriction , Dietary Supplements , Hormesis/physiology , Humans , Longevity/physiology
11.
Nanomedicine (Lond) ; 13(14): 1787-1793, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29786466

ABSTRACT

We observed earlier that mineralo-organic nanoparticles form in human body fluids when the concentrations of calcium, carbonate and phosphate exceed saturation. The particles have been shown to represent mineral precursors in developing bones and teeth as well as in ectopic calcification and kidney stones. Recent studies suggest that the mineral particles may also be involved in other physiological processes, including immune tolerance against the gut microbiota and food antigens. We review here the involvement of mineralo-organic nanoparticles in physiological and pathological processes and discuss recent findings that reveal novel and unexpected roles for these particles in the human body.

12.
Sci Rep ; 7(1): 16628, 2017 11 30.
Article in English | MEDLINE | ID: mdl-29192209

ABSTRACT

Calcium phosphate-based mineralo-organic particles form spontaneously in the body and may represent precursors of ectopic calcification. We have shown earlier that these particles induce activation of caspase-1 and secretion of IL-1ß by macrophages. However, whether the particles may produce other effects on immune cells is unclear. Here, we show that these particles induce the release of neutrophil extracellular traps (NETs) in a size-dependent manner by human neutrophils. Intracellular production of reactive oxygen species is required for particle-induced NET release by neutrophils. NETs contain the high-mobility group protein B1 (HMGB1), a DNA-binding protein capable of inducing secretion of TNF-α by a monocyte/macrophage cell line and primary macrophages. HMGB1 functions as a ligand of Toll-like receptors 2 and 4 on macrophages, leading to activation of the MyD88 pathway and TNF-α production. Furthermore, HMGB1 is critical to activate the particle-induced pro-inflammatory cascade in the peritoneum of mice. These results indicate that mineral particles promote pro-inflammatory responses by engaging neutrophils and macrophages via signaling of danger signals through NETs.


Subject(s)
Extracellular Traps/immunology , HMGB1 Protein/metabolism , Immunity, Innate , Immunomodulation , Minerals/immunology , Neutrophils/immunology , Neutrophils/metabolism , Animals , Cell Line , Female , HMGB1 Protein/genetics , Humans , Macrophage Activation , Macrophages/immunology , Macrophages/metabolism , Male , Mice , Models, Molecular , Myeloid Differentiation Factor 88/metabolism , Reactive Oxygen Species , Signal Transduction , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/metabolism , Tumor Necrosis Factor-alpha/biosynthesis
13.
Sci Rep ; 7(1): 3698, 2017 06 16.
Article in English | MEDLINE | ID: mdl-28623253

ABSTRACT

CCL5/RANTES, a chemoattractant for myeloid cells, is induced by hepatic ischemia/reperfusion injury (IRI). The roles of CCL5 in hepatic IRI were carried out by means of CCL5 immunodepletion, antagonistic competition by Met-CCL5, and treatment with recombinant murine CCL5 (rmCCL5). Depletion or inhibition of CCL5 reduced severity of hepatic IRI, whereas rmCCL5 treatment aggravated liver IRI as manifested in elevated serum alanine aminotransferase (ALT) and tissue myeloperoxidase (MPO) levels. Moreover, IRI severity was reduced in CCL5-knockout (CCL5-KO) mice versus wildtype (WT) mice, with drops in serum ALT level, intrahepatic MPO activity, and histological pathology. Bone marrow transplantion (BMT) studies show that myeloid cells and tissue cells are both required for CCL5-aggravated hepatic IRI. The profile of liver-infiltrating leukocyte subsets after hepatic reperfusion identified CD11b+ cells as the only compartment significantly reduced in CCL5-KO mice versus WT controls at early reperfusion phase. The role of CCL5 recruiting CD11b+ cells in early reperfusion was validated by in vitro transwell migration assay of murine primary macrophages (broadly characterized by their CD11b expression) in response to liver lysates after early reperfusion. Taken together, our results demonstrate a sequence of early events elicited by CCL5 chemoattracting macrophage that result in inflammatory aggravation of hepatic IRI.


Subject(s)
Chemokine CCL5/genetics , Hepatic Insufficiency/etiology , Hepatic Insufficiency/metabolism , Ischemia/metabolism , Macrophages/metabolism , Reperfusion Injury/etiology , Reperfusion Injury/metabolism , Animals , Biomarkers , CCR5 Receptor Antagonists/pharmacology , Cell Proliferation , Chemokine CCL5/metabolism , Disease Models, Animal , Flow Cytometry , Hepatic Insufficiency/drug therapy , Hepatic Insufficiency/pathology , Immunohistochemistry , Immunophenotyping , Liver Function Tests , Macrophages/immunology , Macrophages/pathology , Male , Mice , Mice, Knockout , Receptors, CCR5/genetics , Receptors, CCR5/metabolism , Reperfusion Injury/drug therapy , Reperfusion Injury/pathology
14.
Nanomedicine (Lond) ; 10(24): 3519-35, 2015.
Article in English | MEDLINE | ID: mdl-26429230

ABSTRACT

AIMS: Mineralo-organic nanoparticles (NPs) detected in biological fluids have been described as precursors of physiological and pathological calcifications in the body. Our main objective was to examine the early stages of mineral NP formation in body fluids. MATERIALS & METHODS: A nanomaterial approach based on atomic force microscopy, dynamic light scattering, electron microscopy and spectroscopy was used. RESULTS: The mineral particles, which contain the serum proteins albumin and fetuin-A, initially precipitate in the form of round amorphous NPs that gradually grow in size, aggregate and coalesce to form crystalline mineral films similar to the structures observed in calcified human arteries. CONCLUSION: Our study reveals the early stages of particle formation and provides a platform to analyze the role(s) of mineralo-organic NPs in human tissues.


Subject(s)
Biofilms/drug effects , Nanoparticles/chemistry , Serum/chemistry , Biofilms/growth & development , Body Fluids/drug effects , Humans , Microscopy, Electron, Transmission , Minerals/chemistry , Minerals/therapeutic use , Nanoparticles/therapeutic use , Nanoparticles/ultrastructure , Organic Chemicals/chemistry , Organic Chemicals/therapeutic use
15.
Gut ; 64(7): 1132-47, 2015 Jul.
Article in English | MEDLINE | ID: mdl-24939570

ABSTRACT

OBJECTIVES: Endothelial progenitor cells (EPCs) circulate with increased numbers in the peripheral blood of patients with highly-vascularised hepatocellular carcinoma (HCC) and contribute to angiogenesis and neovascularisation. We hypothesised that angiogenic EPCs, that is, colony forming unit-endothelial cells (CFU-ECs), and outgrowth EPCs, that is, endothelial colony-forming cells, may exert paracrine effects on the behaviours and metastatic capacities of human hepatoma cells. DESIGN: Various molecular and functional approaches ranging from in vitro cell culture studies on molecular signalling to in vivo investigations on cell invasion and orthotropic transplantation models in mice and clinical specimens from patients with HCC were used. RESULTS: Monocyte chemotactic protein-1 (MCP-1) was identified as a critical mediator released from CFU-ECs to contribute to the chemotaxis of Huh7 and Hep3B cells by inducing their microRNA-21 (miR-21) biogenesis through the C-C chemokine receptor-2/c-Jun N-terminal kinase/activator protein-1 signalling cascade. CFU-EC-induction of miR-21 in these cells activated their Rac1 and matrix metallopeptidase-9 by silencing Rho GTPase-activating protein-24 and tissue inhibitor of metalloproteinase-3, respectively, leading to increased cell mobility. MCP-1-induction of miR-21 induced epithelial-mesenchymal transformation of Huh7 cells in vitro and their intrahepatic metastatic capability in vivo. Moreover, increased numbers of MCP-1(+) EPCs and their positive correlations with miR-21 induction and metastatic stages in human HCC were found. CONCLUSIONS: Our results provide new insights into the complexity of EPC-HCC interactions and indicate that anticancer therapies targeting either the MCP-1 released from angiogenic EPCs or the miR-21 biogenesis in HCC cells may prevent the malignant progression of primary tumours.


Subject(s)
Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/physiopathology , Chemokine CCL2/physiology , Endothelial Progenitor Cells/physiology , Liver Neoplasms/pathology , Liver Neoplasms/physiopathology , MicroRNAs/physiology , Cell Line, Tumor , Chemotaxis/physiology , Coculture Techniques , Humans , MAP Kinase Signaling System/physiology , Matrix Metalloproteinase 9/metabolism , rac1 GTP-Binding Protein/physiology
16.
Nanomedicine (Lond) ; 9(4): 483-99, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24787439

ABSTRACT

Nanobacteria have been at the center of a major scientific controversy in recent years owing to claims that they represent not only the smallest living microorganisms on earth but also new emerging pathogens associated with several human diseases. We and others have carefully examined these claims and concluded that nanobacteria are in fact nonliving mineralo-organic nanoparticles (NPs) that form spontaneously in body fluids. We have shown that these mineral particles possess intriguing biomimetic properties that include the formation of cell- and tissue-like morphologies and the possibility to grow, proliferate and propagate by subculture. Similar mineral NPs (bions) have now been found in both physiological and pathological calcification processes and they appear to represent precursors of physiological calcification cycles, which may at times go awry in disease conditions. Furthermore, by functioning at the nanoscale, these mineralo-organic NPs or bions may shed light on the fate of nanomaterials in the body, from both nanotoxicological and nanopathological perspectives.


Subject(s)
Calcifying Nanoparticles/metabolism , Minerals/metabolism , Nanoparticles/ultrastructure , Animals , Calcifying Nanoparticles/chemistry , Crystallization , Humans , Minerals/chemistry , Nanomedicine , Nanoparticles/chemistry , Nanoparticles/metabolism
17.
Small ; 9(13): 2297-307, 2013 Jul 08.
Article in English | MEDLINE | ID: mdl-23255529

ABSTRACT

Recent studies indicate that mineral nanoparticles (NPs) form spontaneously in human body fluids. These biological NPs represent mineral precursors that are associated with ectopic calcifications seen in various human diseases. However, the parameters that control the formation of mineral NPs and their possible effects on human cells remain poorly understood. Here a nanomaterial approach to study the formation of biomimetic calcium phosphate NPs comparable to their physiological counterparts is described. Particle sizing using dynamic light scattering reveals that serum and ion concentrations within the physiological range yield NPs below 100 nm in diameter. While the particles are phagocytosed by macrophages in a size-independent manner, only large particles or NP aggregates in the micrometer range induce cellular responses that include production of mitochondrial reactive oxygen species, caspase-1 activation, and secretion of interleukin-1ß (IL-1ß). A comprehensive proteomic analysis reveals that the particle-bound proteins are similar in terms of their identity and number, regardless of particle size, suggesting that protein adsorption is independent of particle size and curvature. In conclusion, the conditions underlying the formation of mineralo-protein particles are similar to the ones that form in vivo. While mineral NPs do not activate immune cells, they may become pro-inflammatory and contribute to pathological processes once they aggregate and form larger mineral particles.


Subject(s)
Biomimetic Materials/chemistry , Body Fluids/metabolism , Calcium/chemistry , Chemical Phenomena , Nanoparticles/chemistry , Proteins/metabolism , Adsorption , Animals , Biomimetic Materials/pharmacology , Calcium/pharmacology , Cell Line , Humans , Inflammation/pathology , Ions , Macrophages/drug effects , Macrophages/pathology , Macrophages/ultrastructure , Mice , Nanoparticles/ultrastructure , Particle Size , Phagocytosis , Proteins/chemistry , Proteins/pharmacology , Serum , Static Electricity
18.
Cell Signal ; 24(3): 779-93, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22120522

ABSTRACT

Endothelial progenitor cells (EPCs) participate in the neovascularization processes in the development of hepatocellular carcinoma (HCC). We investigated whether interactions between EPCs and HCC cells affect chemotactic and pro-inflammatory activities of EPCs. Two distinct phenotypes of circulating EPCs, i.e., myeloid-derived EPCs (colony forming unit-endothelial cells, CFU-ECs) and outgrowth EPCs (endothelial-colony forming cells, ECFCs), were co-cultured with Huh7 and Hep3B cells by using transwell chamber and IBIDI(TM) Culture-Inserts and µ-slide plates. Transwell and horizontal migration/invasion assays and time-lapse microscopy were used to monitor and analyze the migration and invasion of EPCs induced by these HCC cells. A human cytokine antibody array was used to compare protein expression profiles in EPCs and HCC cells. Flow cytometry and electromobility shift analysis were used to detect nuclear factor-κB (NF-κB)-DNA binding activity and pro-inflammatory adhesion molecule expression in EPCs. Ectopic full-length CC chemokine receptor 6 (CCR6) plasmid was used to transfect into ECFCs to investigate the role of CCR6 in HCC-induced EPC migration and invasion. The results show that co-culture with Huh7 and Hep3B cells induces the expression of endothelial cell (EC) markers KDR, Flt1, CD31 and VE-cadherin in CFU-ECs, but down-regulates the expressions of CD31 and VE-cadherin in ECFCs. These HCC cells induce migration and invasion of CFU-ECs, but not ECFCs, and do not affect the cell cycle distribution in these EPCs. Cytokine protein array identifies macrophage inflammatory protein-3α (MIP-3α) produced by HCC cells as a critical factor responsible for the HCC-induced chemotaxis of CFU-ECs, which highly express the specific MIP-3α counterreceptor CCR6. Overexpressing CCR6 in ECFCs significantly increases their chemotaxis in response to HCC cells. Co-culturing EPCs with HCC cells results in decreases in NF-κB binding activity and hence intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin expressions in EPCs. Our results indicate that HCC cells exert differential effects on CFU-ECs and ECFCs, with increased chemotaxis for CFU-ECs, but not ECFCs. This HCC-induced chemotaxis of CFU-ECs is mediated by MIP-3α produced by HCC cells, which targets to CCR6 on CFU-ECs. Tumors may provide a humoral microenvironment to attenuate the pro-inflammatory activity of EPCs, which might be associated with the tumor escape mechanism.


Subject(s)
Carcinoma, Hepatocellular/physiopathology , Chemotaxis , Liver Neoplasms/physiopathology , Stem Cells/cytology , Antigens, CD/metabolism , Cadherins/metabolism , Cell Movement , Cells, Cultured , Chemokine CCL20/metabolism , Coculture Techniques , Cytokines/metabolism , Humans , NF-kappa B/metabolism , Platelet Endothelial Cell Adhesion Molecule-1/metabolism , Protein Array Analysis , Receptors, CCR6/genetics , Receptors, CCR6/metabolism , Stem Cells/metabolism
19.
Nanomedicine (Lond) ; 6(4): 643-58, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21506688

ABSTRACT

AIM: While nanoparticles (NPs) have been shown to form spontaneously in body fluids such as serum, the possible implications of these NPs for cell cultures that use supporting media containing serum remain unclear. To understand the de novo formation of NPs, we delineated their growth characteristics, chemical composition and interaction with cells in culture. MATERIALS & METHODS: Serum-derived particles were analyzed using a combination of dynamic light scattering, turbidity measurements, spectroscopic techniques and optical/electron microscopies. RESULTS: NPs were found in serum and in serum-containing medium and they increased in size and number during incubation. The mineral particles, consisting mainly of calcium carbonate phosphate bound to organics such as proteins, underwent an amorphous-to-crystalline transformation with time. Serum-derived particles were internalized by the cells tested, eventually reaching lysosomal compartments. CONCLUSION: The spontaneous formation of serum-derived NPs and their internalization by cells may have overlooked effects on cultured cells in vitro as well as potential pathophysiological consequences in vivo.


Subject(s)
Nanoparticles/chemistry , Nanoparticles/ultrastructure , Animals , Calcium Carbonate/chemistry , Cell Line , Mice , Microscopy, Confocal , Microscopy, Electron, Transmission , Spectrometry, X-Ray Emission , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
20.
Am J Physiol Cell Physiol ; 298(5): C1140-50, 2010 May.
Article in English | MEDLINE | ID: mdl-20181932

ABSTRACT

Vascular endothelial (VE)-cadherin is localized to the endothelial borders and the adherens junctions, which are regulated by changes in mitogen-activated protein (MAP) kinases, GTPases, and intracellular calcium. We previously showed that melanoma cells induce VE-cadherin disassembly through contact with human umbilical vein endothelial cells in coculture. However, the exact mechanism by which melanoma cells signal endothelial cells to induce VE-cadherin junction disassembly is not well understood. In this study, VE-cadherin junction disassembly was further examined under fluorescence microscopy. We found that melanoma-induced VE-cadherin junction disassembly and upregulation of p38 MAP kinase in endothelial cells is regulated by both soluble factors from melanomas, particularly interleukin (IL)-8, IL-6, and IL-1beta, and through vascular cell adhesion molecule-1. Neutralizing melanoma-secreted soluble factors reduced endothelial gap formation. Endothelial cells transfected with MAP kinase kinase 6, a direct activator of p38 MAP kinase, increased VE-cadherin-mediated gap formation, facilitating melanoma transendothelial migration. In contrast, endothelial cells transfected with small-interfering RNA against p38 MAP kinase expression largely prevented melanoma transendothelial migration in Boyden chamber experiments. These findings indicate that p38 MAP kinase proteins regulate VE-cadherin junction disassembly, facilitating melanoma migration across endothelial cells.


Subject(s)
Antigens, CD/metabolism , Cadherins/metabolism , Cytokines/metabolism , Melanoma/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Antigens, CD/genetics , Cadherins/genetics , Cell Line, Tumor , Cell Movement , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic/physiology , Humans , Vascular Cell Adhesion Molecule-1/metabolism
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