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1.
Am J Physiol Renal Physiol ; 314(4): F501-F516, 2018 04 01.
Article in English | MEDLINE | ID: mdl-29187371

ABSTRACT

The erythropoietin receptor (EpoR) is widely expressed but its renoprotective action is unexplored. To examine the role of EpoR in vivo in the kidney, we induced acute kidney injury (AKI) by ischemia-reperfusion in mice with different EpoR bioactivities in the kidney. EpoR bioactivity was reduced by knockin of wild-type human EpoR, which is hypofunctional relative to murine EpoR, and a renal tubule-specific EpoR knockout. These mice had lower EPO/EpoR activity and lower autophagy flux in renal tubules. Upon AKI induction, they exhibited worse renal function and structural damage, more apoptosis at the acute stage (<7 days), and slower recovery with more tubulointerstitial fibrosis at the subacute stage (14 days). In contrast, mice with hyperactive EpoR signaling from knockin of a constitutively active human EpoR had higher autophagic flux, milder kidney damage, and better renal function at the acute stage but, surprisingly, worse tubulointerstitial fibrosis and renal function at the subacute stage. Either excess or deficient EpoR activity in the kidney was associated with abnormal peritubular capillaries and tubular hypoxia, creating a "U-shaped" relationship. The direct effects of EpoR on tubular cells were confirmed in vitro by a hydrogen peroxide model using primary cultured proximal tubule cells with different EpoR activities. In summary, normal erythropoietin (EPO)/EpoR signaling in renal tubules provides defense against renal tubular injury maintains the autophagy-apoptosis balance and peritubular capillary integrity. High and low EPO/EpoR bioactivities both lead to vascular defect, and high EpoR activity overides the tubular protective effects in AKI recovery.


Subject(s)
Acute Kidney Injury/metabolism , Capillaries/metabolism , Erythropoietin/metabolism , Kidney Tubules, Proximal/blood supply , Kidney Tubules, Proximal/metabolism , Neovascularization, Physiologic , Receptors, Erythropoietin/metabolism , Acute Kidney Injury/genetics , Acute Kidney Injury/pathology , Acute Kidney Injury/physiopathology , Animals , Apoptosis , Autophagy , Capillaries/pathology , Capillaries/physiopathology , Cell Hypoxia , Cells, Cultured , Disease Models, Animal , Fibrosis , Humans , Kidney Tubules, Proximal/pathology , Kidney Tubules, Proximal/physiopathology , Mice, 129 Strain , Mice, Transgenic , Receptors, Erythropoietin/deficiency , Receptors, Erythropoietin/genetics , Signal Transduction
2.
Mol Med Rep ; 27(2)2023 02.
Article in English | MEDLINE | ID: mdl-36579659

ABSTRACT

The mechanism underlying bladder cancer metastasis is associated with tumor angiogenesis. The present study aimed to evaluate the predictive role and value of an angiogenesis­associated long non­coding (lnc)RNA signature in patients with bladder cancer and the role of long intergenic non­coding RNA (LINC)02321 in the progression of this malignancy. Angiogenesis­related lncRNAs were screened using Pearson correlation analysis and the signaturewas constructed using Cox regression analysis and evaluated using the receiver operating characteristic curve. LINC02321, which expressed the largest difference in bladder cancer, was screened using reverse transcription­quantitative PCR. The role of LINC02321 in the malignant progression of bladder cancer was evaluated using Transwell, wound healing and Cell Counting Kit 8 assays. A total of six angiogenesis­associated lncRNAs (USP30­AS1, LINC02321, PSMB8­AS1, KRT7­AS, LINC01767 and OCIAD1­AS1) were identified as candidates for the prognostic signature using Cox regression analysis. The overall survival of patients in the low­risk group was significantly longer compared with that in the high­risk group, with the highest area under the curve value being 0.807. A nomogram was constructed based on the traditional clinical indicators (age, sex, grade, American Joint Committee on Cancer stage) and risk score of patients. Compared with the traditional clinical indicators, the risk score demonstrated better clinical prediction capacity for predicting the prognosis of patients with bladder cancer. The Cancer Genome Atlas prediction and RT­qPCR experimental results demonstrated that only LINC02321 was highly expressed in bladder cancer tissue and promoted the proliferation, invasion, migration and cisplatin resistance of the malignancy. Gene set enrichment, Pearson's correlation analysis and experimental results demonstrated that the VEGFA signalling pathway may be involved in the LINC02321­regulated progression of bladder cancer. In conclusion, the six angiogenesis­associated lncRNA signatures reported in the present study may be used to predict the prognosis of patients with bladder cancer, and LINC02321 promoted malignant progression of bladder cancer via the VEGFA signalling pathway.


Subject(s)
RNA, Long Noncoding , Urinary Bladder Neoplasms , Humans , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Prognosis , Urinary Bladder Neoplasms/genetics , Risk Factors , Signal Transduction , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Gene Expression Regulation, Neoplastic , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism , Thiolester Hydrolases/genetics , Thiolester Hydrolases/metabolism , Mitochondrial Proteins/metabolism
3.
Stem Cell Reports ; 17(4): 979-992, 2022 04 12.
Article in English | MEDLINE | ID: mdl-35245441

ABSTRACT

Cell replacement therapy using ß cells derived from stem cells is a promising alternative to conventional diabetes treatment options. Although current differentiation methods produce glucose-responsive ß cells, they can also yield populations of undesired endocrine progenitors and other proliferating cell types that might interfere with long-term islet function and safety of transplanted cells. Here, we describe the generation of an array of monoclonal antibodies against cell surface markers that selectively label stem cell-derived islet cells. A high-throughput screen identified promising candidates, including three clones that mark a high proportion of endocrine cells in differentiated cultures. A scalable magnetic sorting method was developed to enrich for human pluripotent stem cell (hPSC)-derived islet cells using these three antibodies, leading to the formation of islet-like clusters with improved glucose-stimulated insulin secretion and reduced growth upon transplantation. This strategy should facilitate large-scale production of functional islet clusters from stem cells for disease modeling and cell replacement therapy.


Subject(s)
Insulin-Secreting Cells , Islets of Langerhans , Pluripotent Stem Cells , Cell Differentiation , Glucose/metabolism , Humans , Insulin/metabolism , Insulin Secretion , Insulin-Secreting Cells/metabolism , Pluripotent Stem Cells/metabolism
4.
Life Sci ; 294: 120383, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35143827

ABSTRACT

AIMS: Small molecule compound tyrphostin A9 (A9), an inhibitor of platelet-derived growth factor (PDGF) receptor, was previously reported by our group to stimulate extracellular signal-regulated kinase 1 (ERK1) and 2 (ERK2) in neuronal cells in a PDGF receptor-irrelevant manner. The study aimed to investigate whether A9 could protect axons in experimental autoimmune encephalomyelitis through activation of ERKs. MAIN METHODS: A9 treatment on the protection on neurite outgrowth in SH-SY5Y neuroblastoma cells and primary substantia nigra neuron cultures from the neurotoxin MPP+ were analyzed. Then, clinical symptoms as well as ERK1/2 activation, axonal protection induction, and the abundance increases of the regeneration biomarker GAP-43 in the CNS in the relapsing-remitting experimental autoimmune encephalomyelitis (EAE) model were verified. KEY FINDINGS: A9 treatment could stimulate neurite outgrowth in SH-SY5Y neuroblastoma cells and protect primary substantia nigra neuron cultures from the neurotoxin MPP+. In the relapsing-remitting EAE model, oral administration of A9 successfully ameliorated clinical symptoms, activated ERK1/2, induced axonal protection, and increased the abundance of the regeneration biomarker GAP-43 in the CNS. Interestingly, gene deficiency of ERK1 or ERK2 disrupted the beneficial effects of A9 in MOG-35-55-induced EAE. SIGNIFICANCE: These results demonstrated that small molecule compounds that stimulate persistent ERK activation in vitro and in vivo may be useful in protective or restorative treatment for neurodegenerative diseases.


Subject(s)
Axons/drug effects , Disease Models, Animal , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation/drug effects , Neuroblastoma/drug therapy , Tyrphostins/pharmacology , Animals , Encephalomyelitis, Autoimmune, Experimental/etiology , Encephalomyelitis, Autoimmune, Experimental/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , Extracellular Signal-Regulated MAP Kinases/genetics , Female , Humans , Mice , Mice, Inbred C57BL , Neuroblastoma/metabolism , Neuroblastoma/pathology , Rats , Rats, Sprague-Dawley
5.
J Cell Biol ; 168(4): 655-66, 2005 Feb 14.
Article in English | MEDLINE | ID: mdl-15699217

ABSTRACT

Schwann cells form basal laminae (BLs) containing laminin-2 (Ln-2; heterotrimer alpha2beta1gamma1) and Ln-8 (alpha4beta1gamma1). Loss of Ln-2 in humans and mice carrying alpha2-chain mutations prevents developing Schwann cells from fully defasciculating axons, resulting in partial amyelination. The principal pathogenic mechanism is thought to derive from structural defects in Schwann cell BLs, which Ln-2 scaffolds. However, we found loss of Ln-8 caused partial amyelination in mice without affecting BL structure or Ln-2 levels. Combined Ln-2/Ln-8 deficiency caused nearly complete amyelination, revealing Ln-2 and -8 together have a dominant role in defasciculation, and that Ln-8 promotes myelination without BLs. Transgenic Ln-10 (alpha5beta1gamma1) expression also promoted myelination without BL formation. Rather than BL structure, we found Ln-2 and -8 were specifically required for the increased perinatal Schwann cell proliferation that attends myelination. Purified Ln-2 and -8 directly enhanced in vitro Schwann cell proliferation in collaboration with autocrine factors, suggesting Lns control the onset of myelination by modulating responses to mitogens in vivo.


Subject(s)
Axons/metabolism , Basement Membrane/metabolism , Laminin/metabolism , Myelin Sheath/metabolism , Schwann Cells/metabolism , Animals , Axons/pathology , Basement Membrane/pathology , Behavior, Animal , Cell Adhesion/physiology , Cell Proliferation , Cells, Cultured , Central Nervous System/metabolism , Central Nervous System/pathology , Humans , Laminin/genetics , Mice , Mice, Transgenic , Myelin Sheath/pathology , Rats , Schwann Cells/pathology
6.
Foods ; 9(4)2020 Apr 08.
Article in English | MEDLINE | ID: mdl-32276425

ABSTRACT

The fast-food service industry has been growing rapidly across China over the last few decades. In accordance with the rising consumption level in the country, Chinese customers care increasingly about their food choices. The purpose of this study is to investigate the factors that can influence customer satisfaction, loyalty, and happiness, with a particular focus on the moderating role of gender. Data were collected through an online survey completed by customers who visited Western fast-food restaurants (KFC, McDonalds, etc.) in China. The structural equation model was applied to test 12 hypotheses. Results showed that perceived price, food, service, and physical environment quality positively affected customer satisfaction. Perceived price can significantly influence customers' judgement of the quality dimensions of a restaurant. Moreover, customer satisfaction and happiness can lead to a sense of loyalty. Happiness functions as a mediator between satisfaction and loyalty. Nonetheless, our findings indicated that customers' perceptions of food quality based on price and satisfaction levels based on service quality differ significantly between the genders, which demonstrated that gender moderation exists in food consumption. This study will contribute to a better understanding of managerial and theoretical perspectives, which will be beneficial for subsequent research.

7.
Zhongguo Zhong Yao Za Zhi ; 32(5): 391-3, 2007 Mar.
Article in Zh | MEDLINE | ID: mdl-17511141

ABSTRACT

OBJECTIVE: To optimize the different components proportions of the Realgar floating tablets for gastric retention by uniform design and correlation analysis. METHOD: With the different dosage of hydroxypropyl methyl cellulose (HPMC) as the tablets frame matrix, uniform design and correlation analysis were used to optimize the best component proportions of formula, and to measure the dissolution of the tablets in vitro. RESULT: Dissolution of the tablets in vitro was conformed to the expectation of experiment. The drug-release mechanism was by diffusion and corrosion at the same time. CONCLUSION: The Realgar floating tablets for gastric retention achieved the goal of design, which demand sustained release and safety.


Subject(s)
Arsenicals/chemistry , Gastric Mucosa/metabolism , Materia Medica/chemistry , Sulfides/chemistry , Technology, Pharmaceutical/methods , Administration, Oral , Arsenicals/administration & dosage , Arsenicals/pharmacokinetics , Delayed-Action Preparations , Hypromellose Derivatives , Materia Medica/administration & dosage , Materia Medica/pharmacokinetics , Methylcellulose/analogs & derivatives , Methylcellulose/chemistry , Povidone/chemistry , Solubility , Sulfides/administration & dosage , Sulfides/pharmacokinetics , Tablets
8.
J Pharm Pharmacol ; 57(9): 1221-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16105244

ABSTRACT

Axonal regeneration is important for functional recovery following nerve damage. Centella asiatica Urban herb, also known as Hydrocotyle asiatica L., has been used in Ayurvedic medicine for centuries as a nerve tonic. Here, we show that Centella asiatica ethanolic extract (100 microg mL-1) elicits a marked increase in neurite outgrowth in human SH-SY5Y cells in the presence of nerve growth factor (NGF). However, a water extract of Centella was ineffective at 100 microg mL-1. Sub-fractions of Centella ethanolic extract, obtained through silica-gel chromatography, were tested (100 microg mL-1) for neurite elongation in the presence of NGF. Greatest activity was found with a non-polar fraction (GKF4). Relatively polar fractions (GKF10 to GKF13) also showed activity, albeit less than GKF4. Thus, Centella contains more than one active component. Asiatic acid (AA), a triterpenoid compound found in Centella ethanolic extract and GKF4, showed marked activity at 1 microM (microg mL-1). AA was not present in GKF10 to GKF13, further indicating that other active components must be present. Neurite elongation by AA was completely blocked by the extracellular-signal-regulated kinase (ERK) pathway inhibitor PD 098059 (10 microM). Male Sprague-Dawley rats given Centella ethanolic extract in their drinking water (300-330 mg kg-1 daily) demonstrated more rapid functional recovery and increased axonal regeneration (larger calibre axons and greater numbers of myelinated axons) compared with controls, indicating that the axons grew at a faster rate. Taken together, our findings indicate that components in Centella ethanolic extract may be useful for accelerating repair of damaged neurons.


Subject(s)
Administration, Oral , Centella/chemistry , Nerve Regeneration/drug effects , Neurites/drug effects , Animals , Cell Line, Tumor , Disease Models, Animal , Ethanol/chemistry , Flavonoids/pharmacology , Humans , Male , Medicine, Ayurvedic , Nerve Crush , Nerve Regeneration/physiology , Neurites/ultrastructure , Pentacyclic Triterpenes , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Rats , Rats, Sprague-Dawley , Sciatic Nerve/drug effects , Sciatic Nerve/pathology , Sciatic Nerve/physiology , Triterpenes/antagonists & inhibitors , Triterpenes/chemistry , Triterpenes/pharmacology
9.
Stem Cell Res ; 15(1): 172-81, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26079872

ABSTRACT

Novel cell surface-reactive monoclonal antibodies generated against extrahepatic biliary cells were developed for the isolation and characterization of different cell subsets from normal adult human gallbladder. Eleven antigenically distinct gallbladder subpopulations were isolated by fluorescence-activated cell sorting. They were classified into epithelial, mesenchymal, and pancreatobiliary (PDX1(+)SOX9(+)) subsets based on gene expression profiling. These antigenically distinct human gallbladder cell subsets could potentially also reflect different functional properties in regards to bile physiology, cell renewal and plasticity. Three of the novel monoclonal antibodies differentially labeled archival sections of primary carcinoma of human gallbladder relative to normal tissue. The novel monoclonal antibodies described herein enable the identification and characterization of antigenically diverse cell subsets within adult human gallbladder and are putative tumor biomarkers.


Subject(s)
Biomarkers/metabolism , Gallbladder/metabolism , Adenocarcinoma/pathology , Adult , Animals , Antibodies/immunology , Bile Ducts, Extrahepatic/metabolism , Cell Line, Tumor , Cell Separation , Cystic Duct/metabolism , Epithelial Cells/cytology , Female , Flow Cytometry , Fluorescent Antibody Technique , Gallbladder/pathology , Gene Expression Regulation , Humans , Mesoderm/cytology , Mice, Inbred BALB C , Pancreas/metabolism , Staining and Labeling
10.
Int J Alzheimers Dis ; 2012: 381974, 2012.
Article in English | MEDLINE | ID: mdl-22506133

ABSTRACT

Centella asiatica (CA), commonly named gotu kola, is an Ayurvedic herb used to enhance memory and nerve function. To investigate the potential use of CA in Alzheimer's disease (AD), we examined the effects of a water extract of CA (GKW) in the Tg2576 mouse, a murine model of AD with high ß-amyloid burden. Orally administered GKW attenuated ß-amyloid-associated behavioral abnormalities in these mice. In vitro, GKW protected SH-SY5Y cells and MC65 human neuroblastoma cells from toxicity induced by exogenously added and endogenously generated ß-amyloid, respectively. GKW prevented intracellular ß-amyloid aggregate formation in MC65 cells. GKW did not show anticholinesterase activity or protect neurons from oxidative damage and glutamate toxicity, mechanisms of current AD therapies. GKW is rich in phenolic compounds and does not contain asiatic acid, a known CA neuroprotective triterpene. CA thus offers a unique therapeutic mechanism and novel active compounds of potential relevance to the treatment of AD.

11.
Mol Cell Endocrinol ; 339(1-2): 144-50, 2011 Jun 06.
Article in English | MEDLINE | ID: mdl-21539888

ABSTRACT

Tools permitting the isolation of live pancreatic cell subsets for culture and/or molecular analysis are limited. To address this, we developed a collection of monoclonal antibodies with selective surface labeling of endocrine and exocrine pancreatic cell types. Cell type labeling specificity and cell surface reactivity were validated on mouse pancreatic sections and by gene expression analysis of cells isolated using FACS. Five antibodies which marked populations of particular interest were used to isolate and study viable populations of purified pancreatic ducts, acinar cells, and subsets of acinar cells from whole pancreatic tissue or of alpha or beta cells from isolated mouse islets. Gene expression analysis showed the presence of known endocrine markers in alpha and beta cell populations and revealed that TTR and DPPIV are primarily expressed in alpha cells whereas DGKB and GPM6A have a beta cell specific expression profile.


Subject(s)
Antigens, Surface/metabolism , Cell Separation/methods , Glucagon-Secreting Cells/metabolism , Insulin-Secreting Cells/metabolism , Pancreatic Ducts/metabolism , Animals , Antibodies, Monoclonal, Murine-Derived , Antigens, Surface/immunology , Diacylglycerol Kinase/metabolism , Dipeptidyl Peptidase 4/metabolism , Flow Cytometry/methods , Membrane Glycoproteins/metabolism , Mice , Mice, Inbred BALB C , Nerve Tissue Proteins/metabolism , Pancreas/cytology , Pancreas/embryology , Pancreatic Ducts/cytology , Pancreatic Ducts/embryology , Prealbumin/metabolism , Rats , Rats, Inbred F344 , Staining and Labeling
12.
Neurosignals ; 13(3): 122-9, 2004.
Article in English | MEDLINE | ID: mdl-15067199

ABSTRACT

The immunosuppressant drug FK506 (tacrolimus) accelerates nerve regeneration in vivo and increases neurite elongation in vitro. We have proposed that the mechanism involves binding to the FK506-binding protein 52, a chaperone component of mature steroid receptor complexes, and a subsequent 'gain-of-function' involving p23 dissociation from Hsp-90 in the complex and extracellular signal-regulated kinase (ERK) activation. Here, we tested the involvement of the ERK and p23 in neurite elongation by FK506 in human SH-SY5Y cells. FK506 (10 nM) increased ERK1/2 phosphorylation at 12 and 24 h, eliciting a 3.5-fold increase at 24 h, which was inhibited in a concentration-dependent manner by an antibody (JJ3) to recombinant human p23. Neurite elongation by FK506 (10 nM), determined by measuring neurite lengths at 96 and 168 h, was completely blocked by the mitogen-activated protein kinase inhibitor PD 098059 (10 microM) and prevented, in a concentration-dependent fashion, by the p23 antibody. Taken together, the results demonstrate the functional role for ERK and p23 in the neurite elongation activity of FK506 and reveal a novel signal transduction pathway involving p23 activation of ERK. We suggest that compounds that stimulate or mimic p23 may be useful for accelerating nerve regeneration.


Subject(s)
DNA-Binding Proteins/metabolism , Immunosuppressive Agents/pharmacology , Mitogen-Activated Protein Kinases/metabolism , Neurites/drug effects , Tacrolimus/pharmacology , Blotting, Western/methods , Cell Line, Tumor , Drug Interactions , Flavonoids/pharmacology , Humans , Nerve Growth Factor/pharmacology , Neurites/physiology , Neuroblastoma , Phosphorylation/drug effects , Signal Transduction , Time Factors
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