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1.
Nat Commun ; 15(1): 3068, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38594269

ABSTRACT

Polyunsaturated fatty acids (PUFAs), which cannot be synthesized by animals and must be supplied from the diet, have been strongly associated with human health. However, the mechanisms for their accretion remain poorly understood. Here, we show that LDL receptor-related protein 5 (LRP5), but not its homolog LRP6, selectively transports unesterified PUFAs into a number of cell types. The LDLa ligand-binding repeats of LRP5 directly bind to PUFAs and are required and sufficient for PUFA transport. In contrast to the known PUFA transporters Mfsd2a, CD36 and FATP2, LRP5 transports unesterified PUFAs via internalization to intracellular compartments including lysosomes, and n-3 PUFAs depend on this transport mechanism to inhibit mTORC1. This LRP5-mediated PUFA transport mechanism suppresses extracellular trap formation in neutrophils and protects mice from myocardial injury during ischemia-reperfusion. Thus, this study reveals a biologically important mechanism for unesterified PUFA transport to intracellular compartments.


Subject(s)
Fatty Acids, Omega-3 , Fatty Acids, Unsaturated , Animals , Humans , Mice , Diet , Fatty Acids/metabolism , Fatty Acids, Omega-3/pharmacology , Fatty Acids, Unsaturated/metabolism , Receptors, LDL
2.
J Immunol ; 209(4): 723-730, 2022 08 15.
Article in English | MEDLINE | ID: mdl-35914834

ABSTRACT

Severe acute respiratory syndrome coronavirus 2, responsible for the severe acute respiratory syndrome known as COVID-19, has rapidly spread in almost every country and devastated the global economy and health care system. Lung injury is an early disease manifestation believed to be a major contributor to short- and long-term pathological consequences of COVID-19, and thus drug discovery aiming to ameliorate lung injury could be a potential strategy to treat COVID-19 patients. By inducing a severe acute respiratory syndrome-like pulmonary disease model through infecting A/J mice with murine hepatitis virus strain 1 (MHV-1), we show that i.v. administration of pazopanib ameliorates acute lung injuries without affecting MHV-1 replication. Pazopanib reduces cell apoptosis in MHV-1-infected lungs. Furthermore, we also identified that pazopanib has to be given no later than 48 h after the virus infection without compromising the therapeutic effect. Our study provides a potential treatment for coronavirus-induced lung injuries and support for further evaluation of pazopanib in COVID-19 patients.


Subject(s)
COVID-19 Drug Treatment , Lung Injury , Murine hepatitis virus , Animals , Indazoles , Lung , Lung Injury/drug therapy , Mice , Pyrimidines , Sulfonamides/therapeutic use
3.
Sci Transl Med ; 13(591)2021 04 28.
Article in English | MEDLINE | ID: mdl-33910977

ABSTRACT

Acute lung injury (ALI) causes high mortality and lacks any pharmacological intervention. Here, we found that pazopanib ameliorated ALI manifestations and reduced mortality in mouse ALI models and reduced edema in human lung transplantation recipients. Pazopanib inhibits mitogen-activated protein kinase kinase kinase 2 (MAP3K2)- and MAP3K3-mediated phosphorylation of NADPH oxidase 2 subunit p47phox at Ser208 to increase reactive oxygen species (ROS) formation in myeloid cells. Genetic inactivation of MAP3K2 and MAP3K3 in myeloid cells or hematopoietic mutation of p47phox Ser208 to alanine attenuated ALI manifestations and abrogates anti-ALI effects of pazopanib. This myeloid MAP3K2/MAP3K3-p47phox pathway acted via paracrine H2O2 to enhance pulmonary vasculature integrity and promote lung epithelial cell survival and proliferation, leading to increased pulmonary barrier function and resistance to ALI. Thus, pazopanib has the potential to be effective for treating ALI.


Subject(s)
Acute Lung Injury , Indazoles/pharmacology , MAP Kinase Kinase Kinase 2/antagonists & inhibitors , MAP Kinase Kinase Kinase 3/antagonists & inhibitors , Pyrimidines/pharmacology , Sulfonamides/pharmacology , Acute Lung Injury/drug therapy , Animals , Humans , Hydrogen Peroxide , Mice , NADPH Oxidases/metabolism , Phosphorylation , Reactive Oxygen Species
4.
J Neurosci ; 41(17): 3799-3807, 2021 04 28.
Article in English | MEDLINE | ID: mdl-33741723

ABSTRACT

The release of small extracellular vesicles (sEVs) has recently been reported, but knowledge of their function in neuron development remains limited. Using LC-MS/MS, we found that sEVs released from developing cortical neurons in vitro obtained from mice of both sexes were enriched in cytoplasm, exosome, and protein-binding and DNA/RNA-binding pathways. The latter included HDAC2, which was of particular interest, because HDAC2 regulates spine development, and populations of neurons expressing different levels of HDAC2 co-exist in vivo during the period of spine growth. Here, we found that HDAC2 levels decrease in neurons as they acquire synapses and that sEVs from HDAC2-rich neurons regulate HDAC2 signaling in HDAC2-low neurons possibly through HDAC2 transfer. This regulation led to a transcriptional decrease in HDAC2 synaptic targets and the density of excitatory synapses. These data suggest that sEVs provide inductive cell-cell signaling that coordinates the development of dendritic spines via the activation of HDAC2-dependent transcriptional programs.SIGNIFICANCE STATEMENT A role of small extracellular vesicles (sEVs; also called exosomes) in neuronal development is of particular interest, because sEVs could provide a major signaling modality between developing neurons when synapses are not fully functional or immature. However, knowledge of sEVs on neuron, and more precisely spine development, is limited. We provide several lines of evidence that sEVs released from developing cortical neurons regulate the development of dendritic spines via the regulation of HDAC2 signaling. This paracrine communication is temporally restricted during development because of the age-dependent decrease in sEV release as neurons mature and acquire spines.


Subject(s)
Dendritic Spines/physiology , Extracellular Space/physiology , Histone Deacetylase 2/genetics , Histone Deacetylase 2/physiology , Signal Transduction/genetics , Signal Transduction/physiology , Animals , Cytoplasm/metabolism , Exosomes/metabolism , Female , Gene Expression Regulation, Developmental/genetics , Gene Expression Regulation, Developmental/physiology , Male , Mice , Primary Cell Culture , Proteomics , Synapses/physiology
6.
J Immunol ; 204(4): 1012-1021, 2020 02 15.
Article in English | MEDLINE | ID: mdl-31924649

ABSTRACT

Cell polarization is a key step for leukocytes adhesion and transmigration during leukocytes' inflammatory infiltration. Polarized localization of plasma membrane (PM) phosphatidylinositol-4-phosphate (PtdIns4P) directs the polarization of RPH3A, which contains a PtdIns4P binding site. Consequently, RPH3A mediates the RAB21 and PIP5K1C90 polarization, which is important for neutrophil adhesion to endothelia during inflammation. However, the mechanism by which RPH3A is recruited only to PM PtdIns4P rather than Golgi PtdIns4P remains unclear. By using ADP-ribosylation factor 6 (ARF6) small interfering RNA, ARF6 dominant-negative mutant ARF6(T27N), and ARF6 activation inhibitor SecinH3, we demonstrate that ARF6 plays an important role in the polarization of RPH3A, RAB21, and PIP5K1C90 in murine neutrophils. PM ARF6 is polarized and colocalized with RPH3A, RAB21, PIP5K1C90, and PM PtdIns4P in mouse and human neutrophils upon integrin stimulation. Additionally, ARF6 binds to RPH3A and enhances the interaction between the PM PtdIns4P and RPH3A. Consistent with functional roles of polarization of RPH3A, Rab21, and PIP5K1C90, ARF6 is also required for neutrophil adhesion on the inflamed endothelial layer. Our study reveals a previously unknown role of ARF6 in neutrophil polarization as being the coincidence-detection code with PM PtdIns4P. Cooperation of ARF6 and PM PtdIns4P direct RPH3A polarization, which is important for neutrophil firm adhesion to endothelia.


Subject(s)
ADP-Ribosylation Factors/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Endothelium/metabolism , Nerve Tissue Proteins/metabolism , Neutrophil Activation , Neutrophils/immunology , Vesicular Transport Proteins/metabolism , ADP-Ribosylation Factor 6 , Animals , Cell Adhesion/immunology , Cell Line , Cell Membrane/metabolism , Cell Movement/immunology , Endothelial Cells , Endothelium/cytology , Endothelium/immunology , Female , Healthy Volunteers , Humans , Mice , Neutrophils/cytology , Neutrophils/metabolism , Phosphatidylinositol Phosphates/metabolism , Primary Cell Culture , Rabphilin-3A
7.
Sci Rep ; 9(1): 16058, 2019 11 05.
Article in English | MEDLINE | ID: mdl-31690770

ABSTRACT

Tremendous efforts have been made to explore biomarkers for classification and grading on gliomas. The goal of this study was to identify more molecular features that are associated with clinical outcomes by comparing the genomic profiles of primary and recurrent gliomas and determine potential recurrence leading factors that are significantly enriched in relapse tumors. Hybrid capture based next generation sequencing (NGS) analysis was performed on 64 primary and 17 recurrent glioma biopsies. Copy number variation (CNV) was more frequent in recurrent tumors and CDKN2A/B loss was significantly enriched. In addition, overall mutations in cell cycle pathway are more common in relapse tumors. The patterns of gene sets, including IDH1/TERT and IDH1/TP53 exhibited significant difference between the groups. Survival analysis uncovered the worse disease-free survival (DFS) and overall survival (OS) associated with altered copy number and excessive activation of CELL CYCLE pathway. High Tumor Mutation Burden (TMB) was also a biomarker with great potential for poor prognosis. The assessment of genomic characteristics in primary versus recurrent gliomas aids the discovery of potential predictive biomarkers. The prognostic value of TMB in gliomas was raised for the first time.


Subject(s)
Biomarkers, Tumor/genetics , DNA Copy Number Variations , Glioma , Neoplasm Proteins/genetics , Neoplasm Recurrence, Local , Adult , Disease-Free Survival , Female , Glioma/genetics , Glioma/mortality , Glioma/pathology , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Survival Rate
8.
Dev Cell ; 49(2): 206-219.e7, 2019 04 22.
Article in English | MEDLINE | ID: mdl-30930167

ABSTRACT

Cell polarization is important for various biological processes. However, its regulation, particularly initiation, is incompletely understood. Here, we investigated mechanisms by which neutrophils break their symmetry and initiate their cytoskeleton polarization from an apolar state in circulation for their extravasation during inflammation. We show here that a local increase in plasma membrane (PM) curvature resulting from cell contact to a surface triggers the initial breakage of the symmetry of an apolar neutrophil and is required for subsequent polarization events induced by chemical stimulation. This local increase in PM curvature recruits SRGAP2 via its F-BAR domain, which in turn activates PI4KA and results in PM PtdIns4P polarization. Polarized PM PtdIns4P is targeted by RPH3A, which directs PIP5K1C90 and subsequent phosphorylated myosin light chain polarization, and this polarization signaling axis regulates neutrophil firm attachment to endothelium. Thus, this study reveals a mechanism for the initiation of cell cytoskeleton polarization.


Subject(s)
Cell Polarity/physiology , Neutrophils/physiology , Actins/metabolism , Animals , Cell Adhesion , Cell Membrane/metabolism , Cell Membrane/physiology , Cell Movement/physiology , Cell-Matrix Junctions , Cytoskeleton/metabolism , Endothelium/metabolism , Female , GTPase-Activating Proteins/metabolism , GTPase-Activating Proteins/physiology , HEK293 Cells , Humans , Leukocytes/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Minor Histocompatibility Antigens/metabolism , Myosin Light Chains/metabolism , Neutrophils/metabolism , Phosphatidylinositol Phosphates/metabolism , Phosphorylation , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Signal Transduction
9.
Bone Rep ; 9: 154-158, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30364642

ABSTRACT

CONTEXT: Most heritable causes of low bone mass in children occur due to mutations affecting type 1 collagen. We describe two related patients with low bone mass and fracture without mutations in the type 1 collagen genes. CASE DESCRIPTION: We describe the index case of a 10-year-old girl with low-impact fractures in childhood and her 59-year-old father with traumatic fractures in adulthood, both with low bone mineral density. They were found to have the same heterozygous missense mutation in the WNT1 gene (p.Gly222Arg), occurring in a highly conserved WNT motif in close proximity to the Frizzled binding site. CONCLUSIONS: The WNT-ligand WNT1, signaling through the canonical WNT-ß-catenin pathway, plays a critical role in skeletal development, adult skeletal homeostasis, and bone remodeling. Biallelic mutations have been described and are associated with moderate to severe osteogenesis imperfecta, in some cases with extra-skeletal manifestations. Patients with monoallelic mutations, as in our case, seem to present with low bone mineral density and less severe disease. The phenotypic difference between biallelic and monoallelic mutations highlights that the aberrant protein in monoallelic mutations may exert a dominant negative effect on the wild type protein as heterozygous carriers in families with biallelic disease are usually asymptomatic. With better understanding of disorders associated with WNT1 mutations, therapies targeting this signaling pathway may offer therapeutic benefit.

10.
Cell Rep ; 19(12): 2586-2597, 2017 06 20.
Article in English | MEDLINE | ID: mdl-28636945

ABSTRACT

Polarized vesicle transport plays an important role in cell polarization, but the mechanisms underlying this process and its role in innate immune responses are not well understood. Here, we describe a phosphorylation-regulated polarization mechanism that is important for neutrophil adhesion to endothelial cells during inflammatory responses. We show that the protein kinase PKN1 phosphorylates RPH3A, which enhances binding of RPH3A to guanosine triphosphate (GTP)-bound RAB21. These interactions are important for polarized localization of RAB21 and RPH3A in neutrophils, which leads to PIP5K1C90 polarization. Consistent with the roles of PIP5K1C90 polarization, the lack of PKN1 or RPH3A impairs neutrophil integrin activation, adhesion to endothelial cells, and infiltration in inflammatory models. Furthermore, myeloid-specific loss of PKN1 decreases tissue injury in a renal ischemia-reperfusion model. Thus, this study characterizes a mechanism for protein polarization in neutrophils and identifies a potential protein kinase target for therapeutic intervention in reperfusion-related tissue injury.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Kidney/blood supply , Nerve Tissue Proteins/metabolism , Neutrophils/physiology , Protein Kinase C/physiology , Vesicular Transport Proteins/metabolism , rab GTP-Binding Proteins/metabolism , Animals , Cell Adhesion , Cell Polarity , Female , Kidney/pathology , Male , Mice, Inbred C57BL , Mice, Transgenic , Phosphorylation , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Protein Processing, Post-Translational , Protein Transport , Reperfusion Injury/enzymology , Reperfusion Injury/immunology , Reperfusion Injury/pathology , Transendothelial and Transepithelial Migration , Transport Vesicles/metabolism , Rabphilin-3A
12.
Nat Med ; 22(9): 1033-1042, 2016 09.
Article in English | MEDLINE | ID: mdl-27548575

ABSTRACT

Cerebral cavernous malformations (CCMs) are vascular malformations that affect the central nervous system and result in cerebral hemorrhage, seizure and stroke. CCMs arise from loss-of-function mutations in one of three genes: KRIT1 (also known as CCM1), CCM2 or PDCD10 (also known as CCM3). PDCD10 mutations in humans often result in a more severe form of the disease relative to mutations in the other two CCM genes, and PDCD10-knockout mice show severe defects, the mechanistic basis for which is unclear. We have recently reported that CCM3 regulates exocytosis mediated by the UNC13 family of exocytic regulatory proteins. Here, in investigating the role of endothelial cell exocytosis in CCM disease progression, we found that CCM3 suppresses UNC13B- and vesicle-associated membrane protein 3 (VAMP3)-dependent exocytosis of angiopoietin 2 (ANGPT2) in brain endothelial cells. CCM3 deficiency in endothelial cells augments the exocytosis and secretion of ANGPT2, which is associated with destabilized endothelial cell junctions, enlarged lumen formation and endothelial cell-pericyte dissociation. UNC13B deficiency, which blunts ANGPT2 secretion from endothelial cells, or treatment with an ANGPT2-neutralizing antibody normalizes the defects in the brain and retina caused by endothelial-cell-specific CCM3 deficiency, including the disruption of endothelial cell junctions, vessel dilation and pericyte dissociation. Thus, enhanced secretion of ANGPT2 in endothelial cells contributes to the progression of CCM disease, providing a new therapeutic approach for treating this devastating pathology.


Subject(s)
Angiopoietin-2/metabolism , Endothelium, Vascular/metabolism , Exocytosis , Hemangioma, Cavernous, Central Nervous System/genetics , Intracellular Signaling Peptides and Proteins/genetics , Angiopoietin-1/metabolism , Animals , Apoptosis Regulatory Proteins/genetics , Brain , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique , Gene Expression Profiling , Hemangioma, Cavernous, Central Nervous System/metabolism , Humans , Membrane Proteins/genetics , Mice , Nerve Tissue Proteins , Proto-Oncogene Proteins/genetics , Receptor, TIE-2/metabolism , Vesicle-Associated Membrane Protein 3
13.
Oncotarget ; 7(4): 4142-54, 2016 Jan 26.
Article in English | MEDLINE | ID: mdl-26716652

ABSTRACT

RY10-4, a novel protoapigenone analog, shows potent cytotoxicity against human breast cancer cells. However, breast cancer cell lines overexpressing human epidermal growth factor receptor 2 (HER2), SKBR3 and BT474, showed less sensitivity to RY10-4 when compared to breast cancer cells lines expressing lower levels of HER2, such as MDA-MB-231 and MCF-7 cells. This was associated with aberrant hyperactivity in Notch signaling in cells treated with RY10-4, since treatment with RY10-4 causes an increase in Notch activity by 2-to3.5-fold in SKBR3 and BT474 cell lines. The increase in activity was abrogated with a γ-secretase inhibitor, DAPT, or with Notch1 small-interfering RNA (si-Notch1). Cell proliferation was inhibited more effectively by RY10-4 plus DAPT or si-Notch1 than either agent alone. RY10-4 plus DAPT increases apoptosis in both HER2-overexpressing cell lines by two-fold compared to RY10-4 alone, while DAPT alone has no significant effects on apoptosis. In addition, we previously found RY10-4 could inhibit tumor growth through the PI3K/AKT pathway. Here we report that the combination of RY10-4 and DAPT exhibit additive suppression on AKT phosphorylation, contributing to the anti-cancer effects. In an animal model, this combination therapy inhibits the growth of SKBR3 tumor xenografts in nude mice to a greater extent than treatment with either reagent alone. These results indicate that the aberrant activation of Notch signaling impedes the inhibitory effect of RY10-4 on HER2-amplified cell proliferation. Furthermore, these adverse effects can be prevented by treatment combining RY10-4 with a Notch pathway inhibitor.


Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Breast Neoplasms/drug therapy , Dipeptides/pharmacology , Gene Amplification , Pyrones/pharmacology , Receptor, ErbB-2/genetics , Animals , Apoptosis/drug effects , Blotting, Western , Breast Neoplasms/enzymology , Breast Neoplasms/pathology , Cell Proliferation/drug effects , Drug Therapy, Combination , Female , Humans , Immunoenzyme Techniques , Mice , Mice, Inbred BALB C , Mice, Nude , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
14.
Nat Commun ; 6: 8205, 2015 Sep 14.
Article in English | MEDLINE | ID: mdl-26365782

ABSTRACT

Type I phosphatidylinositol phosphate kinase (PIP5K1) phosphorylates the head group of phosphatidylinositol 4-phosphate (PtdIns4P) to generate PtdIns4,5P2, which plays important roles in a wide range of cellular functions including Wnt signalling. However, the lack of its structural information has hindered the understanding of its regulation. Here we report the crystal structure of the catalytic domain of zebrafish PIP5K1A at 3.3 Å resolution. This molecule forms a side-to-side dimer. Mutagenesis study of PIP5K1A reveals two adjacent interfaces for the dimerization and interaction with the DIX domain of the Wnt signalling molecule dishevelled. Although these interfaces are located distally to the catalytic/substrate-binding site, binding to these interfaces either through dimerization or the interaction with DIX stimulates PIP5K1 catalytic activity. DIX binding additionally enhances PIP5K1 substrate binding. Thus, this study elucidates regulatory mechanisms for this lipid kinase and provides a paradigm for the understanding of PIP5K1 regulation by their interacting molecules.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Dimerization , Phosphoproteins/metabolism , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Animals , Binding Sites , Calorimetry , Catalytic Domain , Circular Dichroism , Crystallization , Crystallography, X-Ray , Dishevelled Proteins , HEK293 Cells , Humans , Phosphatidylinositol 4,5-Diphosphate/metabolism , Phosphatidylinositol Phosphates/metabolism , Phosphorylation , Phosphotransferases (Alcohol Group Acceptor)/chemistry , Protein Structure, Tertiary , Zebrafish
15.
Chem Biol Interact ; 209: 25-34, 2014 Feb 25.
Article in English | MEDLINE | ID: mdl-24300195

ABSTRACT

Previous reports suggested that protoapigenone showed remarkable antitumor activities against a broad spectrum of human cancer cell lines, but had no effect on human lung adenocarcinoma A549 cell. The lack of effective remedies had necessitated the application of new therapeutic scheme. A novel compound RY10-4 which has the similar structure close to protoapigenone showed better antitumor activity. Treatment with RY10-4 inhibited the expression of pro-caspase-3, pro-caspase-9, Bcl-2 as well as phosphorylation of signal transducer and activator of transcription-3 (p-STAT3). It also reduced the expressions of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and increases the expressions of reversion-inducing cysteine-rich protein with kazal motifs (RECK), as well as tissue inhibitor of metalloproteinase (TIMP) via inhibiting STAT3 by activating the mitogen-activated protein (MAP) kinases (the c-Jun N-terminal kinase (JNK), the p38 and extracellular signal-regulated kinase (ERK)) in A549 cells treated with RY10-4. Moreover, the cytotoxic effect of RY10-4 was induction of apoptosis in A549 cells by enhancing production of reactive oxygen species (ROS). Taken together, the observations suggested that RY10-4 had affected Bcl-2 family members, caspases, MMPs, TIMPs expressions and ROS production via inhibiting STAT3 activities through ERK and p38 pathways in A549 cells.


Subject(s)
Adenocarcinoma/pathology , Apoptosis/drug effects , Lung Neoplasms/pathology , MAP Kinase Signaling System/physiology , Pyrones/pharmacology , STAT3 Transcription Factor/metabolism , Adenocarcinoma/drug therapy , Adenocarcinoma of Lung , Antineoplastic Agents/pharmacology , Blotting, Western , Cell Cycle/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Humans , Inhibitory Concentration 50 , Lung Neoplasms/drug therapy , Molecular Structure , Neoplasm Invasiveness , Pyrones/chemistry , Reactive Oxygen Species
16.
Toxicol Appl Pharmacol ; 270(2): 122-8, 2013 Jul 15.
Article in English | MEDLINE | ID: mdl-23624174

ABSTRACT

Protoapigenone is a unique flavonoid and enriched in many ferns, showing potent antitumor activity against a broad spectrum of human cancer cell lines. RY10-4, a modified version of protoapigenone, manifested better anti-proliferation activity in human breast cancer cell line MCF-7. The cytotoxicity of RY10-4 against MCF-7 cells is exhibited in both time- and concentration-dependent manners. Here we investigated a novel effect of RY10-4 mediated autophagy in autophagy defect MCF-7 cells. Employing immunofluorescence assay for microtubule-associated protein light-chain 3 (LC3), monodansylcadaverine staining, Western blotting analyses for LC3 and p62 as well as ultrastructural analysis by transmission electron microscopy, we showed that RY10-4 induced autophagy in MCF-7 cells but protoapigenone did not. Meanwhile, inhibition of autophagy by pharmacological and genetic approaches significantly increased the viability of RY10-4 treated cells, suggesting that the autophagy induced by RY10-4 played as a promotion mechanism for cell death. Further studies revealed that RY10-4 suppressed the activation of mTOR and p70S6K via the Akt/mTOR pathway. Our results provided new insights for the mechanism of RY10-4 induced cell death and the cause of RY10-4 showing better antitumor activity than protoapigenone, and supported further evidences for RY10-4 as a lead to design a promising antitumor agent.


Subject(s)
Apoptosis/drug effects , Autophagy/drug effects , Breast Neoplasms/drug therapy , Breast Neoplasms/ethnology , Proto-Oncogene Proteins c-akt/metabolism , Pyrones/pharmacology , TOR Serine-Threonine Kinases/metabolism , Antineoplastic Agents/pharmacology , Blotting, Western , Breast Neoplasms/pathology , Cell Survival/drug effects , Female , Humans , MCF-7 Cells , Microscopy, Electron, Transmission
17.
J Ethnopharmacol ; 147(3): 603-11, 2013 Jun 03.
Article in English | MEDLINE | ID: mdl-23542147

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Adiantum capillus-veneris L. is a wildly distributed plant species and has been extensively used in south of China as traditional folk medicine for the treatment of inflammatory diseases. AIM OF THE STUDY: To investigate the anti-inflammatory effect of ethanolic extracts of Adiantum capillus-veneris L. and the involvement of NF-κB signaling in the regulation of inflammation. MATERIALS AND METHODS: The plant ethanolic extracts were initially tested against lipopolysaccharide (LPS)-induced prostaglandin E2 (PGE2) production in RAW264.7 mouse macrophages, and interleukin 6 (IL-6) and tumor necrosis factor (TNF) production in human U937 monocytes. The effect of the plant extracts on the transcription factor nuclear factor kappa B (NF-κB) pathway was evaluated in TNF-α stimulated HepG2 cells by luciferase gene reporter assay and Western blotting at the transcriptional and translational levels. Subsequently, the inhibition of NF-κB downstream gene expression (IL-8 and ICAM-1) by the plant extracts was assessed via quantitative real time polymerase chain reaction (qPCR). Lastly, the anti-inflammatory activities of the plant extracts in vivo were evaluated by testing spleen index and NF-κB related protein expression in LPS-stimulated CD1 mice. RESULTS: The plant ethanolic extracts effectively suppressed PGE2, IL-6 and TNF release with an IC50 less than 50 µg/ml. Moreover, luciferase expression could be specifically blocked in HepG2 cells, not in HEK293 cells, showing that the plant extracts displayed a cell-specific pattern on NF-κB gene transcription. The assayed biological activity also depended on the order of adding TNF-α and the plant extracts because the plant extracts could only block the NF-κB activation if added earlier but were unable to stop the signal when added after TNF-α. However, the plant extracts did not exert any effect on ubiquitination which regulates several steps in the NF-κB pathway. Additionally, the plant extracts down-regulated phosphorylation of IKKα/ß at S176/180, p38 at T180/Y182 and p65 at S536, but not p65 at S276. This was confirmed by their ability to selectively abrogate the induction of IL-8 transcription, whereas the ICAM-1 gene, which is not transcribed selectively by an NF-κB complex containing a form of p65 phosphorylated on Ser536, did not change. Finally, the plant extracts at 200 µg/mg could normalize the LPS-induced elevation of spleen index as well as NF-κB and p38 activations in CD1 mice. CONCLUSION: The present studies presents the potential utilization of this plant extracts, as a natural resources for the development of an anti-inflammatory medicine.


Subject(s)
Adiantum , Anti-Inflammatory Agents/pharmacology , NF-kappa B/antagonists & inhibitors , Plant Extracts/pharmacology , Animals , Anti-Inflammatory Agents/therapeutic use , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Cytokines/genetics , Cytokines/metabolism , Dinoprostone/metabolism , Ethanol/chemistry , Humans , Inflammation/drug therapy , Inflammation/metabolism , Inflammation/pathology , Inflammation Mediators/metabolism , Intercellular Adhesion Molecule-1/genetics , Lipopolysaccharides , Liver/drug effects , Liver/metabolism , Liver/pathology , Mice , Phytotherapy , Plant Extracts/therapeutic use , Solvents/chemistry , Spleen/drug effects , Spleen/pathology
18.
Cancer Lett ; 324(2): 210-20, 2012 Nov 28.
Article in English | MEDLINE | ID: mdl-22652174

ABSTRACT

RY10-4, a novel protoapigenone analog, shows potent cytotoxicity against a broad spectrum of human cancer cells. Here we investigate its anti-tumor activity on breast cancer. The results indicated that RY10-4 suppressed proliferation, arrested cell cycle, induced apoptosis and inhibited invasion in MDA-MB-231, MCF-7 and SKBR3 breast cancer cells. Western blot analysis showed that RY10-4 down-regulated the PI3K/Akt signaling pathway and inhibited doxorubicin-induced p-Akt. Moreover, it effectively suppressed tumor growth in mice without major side effects. Therefore, RY10-4 had potential anti-tumor activity, and could be used as a lead to design more potent derivatives.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Breast Neoplasms/drug therapy , Cell Movement/drug effects , Phosphatidylinositol 3-Kinase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Pyrones/pharmacology , Signal Transduction/drug effects , Animals , Blotting, Western , Breast Neoplasms/enzymology , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Invasiveness , S Phase Cell Cycle Checkpoints/drug effects , Time Factors , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
19.
Cancer Chemother Pharmacol ; 69(6): 1633-40, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22565593

ABSTRACT

PURPOSE: To assess the anti-angiogenesis potential and mechanism of RY10-4, a derivative of protoapigenone, which was verified the broad-spectrum anti-tumor activities by previous study. METHODS: RY10-4 and RY10-3 were synthesized according to the procedure described. Breast cancer cells MCF-7 and MDA-MB-231 that got the best performance in the previous anti-tumor activity screening were selected for further anti-cancer mechanism research. Firstly, cells proliferation assay of RY10-4 and RY10-3 was used to demonstrate the fact that the 4-hydroxy-2,5-cyclohexadien-1-one system would be the efficient pharmacophore of RY10-4. Then, a series of assays such as human umbilical vein endothelial cells (HUVECs) proliferation assay, HUVECs migration, tube network formation and morphological observations of zebrafish were applied to confirm its anti-angiogenesis activity. Upon RY10-4 treatment, the HIF-1α and VEGF were analyzed by western blot in normoxic and hypoxic conditions, meanwhile the PI3K-AKT-mTOR pathway-related protein such as AKT, p-AKT, mTOR and p-mTOR was also analyzed. RESULTS: In the MCF-7, MDA-MB-231 and HUVECs proliferation assay, RY10-4 that has 4-hydroxy-2,5-cyclohexadien-1-one system showed distinct advantage compared with RY10-3. Tests had verified the anti-angiogenesis capability of RY10-4. Down-regulation of the HIF-1α and inhibition phosphorylation levels of AKT and mTOR were found to be the pathway that RY10-4 exerts its functions on anti-angiogenesis. CONCLUSIONS: The structure of 4-hydroxy-2,5-cyclohexadien-1-one should be the effective pharmacophore of RY10-4. RY10-4 got fine performance in anti-tumor and anti-angiogenesis assay, and thus, the quinol compound will be the new hot-spot for further anti-tumor agency development.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Antineoplastic Agents/pharmacology , Hypoxia-Inducible Factor 1, alpha Subunit/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Pyrones/pharmacology , TOR Serine-Threonine Kinases/antagonists & inhibitors , Animals , Cell Hypoxia , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Down-Regulation , Female , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases/metabolism , Zebrafish
20.
Indian J Pharmacol ; 43(5): 532-5, 2011 Sep.
Article in English | MEDLINE | ID: mdl-22021995

ABSTRACT

OBJECTIVES: Qian-Yu (QY), a Chinese medicine formula, has anti-inflammatory and broad spectrum anti-bacterial activity. This study is undertaken to evaluate the anti-inflammatory effects of Qian-Yu (QY) in chronic bacterial prostatitis (CBP). MATERIALS AND METHODS: The potential of QY in the treatment of CBP was evaluated using a CBP animal model by examining the anti-inflammatory activity. Its consequences were analyzed by immunological and histopathological methods. Experimental chronic bacterial prostatitis was induced by instillation of bacterial suspension of Escherichia coli 7.5 × 10(5) CFU/ml into the prostatic urethra. Animals were followed up for four weeks and then treated with either 7 mg/kg QY or 7 mg/kg positive control agent-Qianlietai (QLT) or 1 ml of phosphate-buffered saline (PBS) for the controls. Ten rats in each group were sacrificed at the end of four weeks. The inhibition of inflammation and its consequences were analyzed histologically. Prostatic IL-8, SIgA and zinc concentrations were measured by ELISA, RIA and ICP-AES, respectively. The data was expressed as mean ± S.D. Least-significant difference (LSD) of one-way ANOVA (SPSS 12.0) was used to determine the differences of scores. RESULTS: The histopathology showed resolving prostatitis in QY-and QLT-treated groups and the immunology showed reduction of IL-8 and increment of SIgA contents in prostatic tissues as compared to the control groups. The prostatic zinc levels were higher in the QY-and QLT-treated groups than those in the controls. These results suggested that QY is effective in CBP treatment.

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