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1.
Front Neurol ; 15: 1400270, 2024.
Article En | MEDLINE | ID: mdl-38798706

Background: Hemorrhagic transformation (HT) is a serious complication after endovascular thrombectomy (EVT) for patients with acute ischemic stroke (AIS). We analyzed the plasma levels of MMP-9 before and after EVT and assessed the temporal changes of MMP-9 that may be associated with, and therefore predict, HT after EVT. Methods: We enrolled 30 AIS patients who received EVT, and 16 (53.3%) developed HT. The levels of MMP-9 in plasma collected from the arteries of AIS patients before and immediately after EVT were measured using ELISA. The percent change in MMP-9 after EVT (after/before) was calculated and compared between patients with and without HT. Results: The median age of the AIS patients was 70 years, and 13 patients (43.3%) were men. The median National Institutes of Health Stroke Scale (NIHSS) scores of patients with HT were 18 on admission and 18 after EVT. The median NIHSS scores of patients without HT were 17 on admission and 11 after EVT. Patients with HT demonstrated significantly greater percentage increases in arterial MMP-9 levels after EVT. Conclusion: Patients with AIS who developed HT had significantly increased arterial MMP-9 levels after EVT, suggesting that the upregulation of MMP-9 following EVT could serve as a predictive biomarker for HT.

2.
Eur J Pharmacol ; 967: 176393, 2024 Mar 15.
Article En | MEDLINE | ID: mdl-38325792

Sunitinib (SUN) is the first-line targeted therapeutic drug for advanced renal cell carcinoma (RCC). However, SUN resistance is frequently observed to result in tumor metastasis, with a poor survival rate. Therefore, finding an effective and safe adjuvant to reduce drug resistance is important for RCC treatment. Pterostilbene (PTE) and 6-shogaol (6-S) are natural phytochemicals found in edible sources and have potential applications against various cancers. However, the biological mechanisms of PTE and 6-S in SUN-resistant RCC are still unclear. Accordingly, this study investigated the regulatory effects of PTE and 6-S on cell survival, drug resistance, and cell invasion in 786-O and SUN-resistant 786-O (786-O SUNR) cells, respectively. The results demonstrated that PTE and 6-S induced apoptosis in both cell lines by upregulating the Bax/Bcl-2 ratio. Additionally, PTE and 6-S increased SUN sensitivity by inhibiting the expression of the RLIP76 transport protein, reduced cell invasion and downregulated MMP expression in both 786-O and 786-O SUNR cells. Mechanistically, PTE, and 6-S significantly and dose-dependently suppressed the RLIP76-initiated Ras/ERK and Akt/mTOR pathways. In summary, PTE and 6-S induce apoptosis, enhance SUN sensitivity, and inhibit migration in both 786-O and 786-O SUNR cells. These novel findings demonstrate the potential of PTE and 6-S as target therapeutic adjuvants for RCC treatment.


Carcinoma, Renal Cell , Catechols , Kidney Neoplasms , Humans , Carcinoma, Renal Cell/metabolism , Sunitinib/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Kidney Neoplasms/pathology , TOR Serine-Threonine Kinases/metabolism , Cell Line, Tumor
3.
Int J Mol Sci ; 24(9)2023 Apr 22.
Article En | MEDLINE | ID: mdl-37175394

Transient global cerebral ischemia (tGCI) resulting from cardiac arrest causes selective neurodegeneration in hippocampal CA1 neurons. Although the effect is clear, the underlying mechanisms directing this process remain unclear. Previous studies have shown that phosphorylation of Erk1/2 promotes cell survival in response to tGCI. DUSP6 (also named MKP3) serves as a cytosolic phosphatase that dephosphorylates Erk1/2, but the role of DUSP6 in tGCI has not been characterized. We found that DUSP6 was specifically induced in the cytoplasm of hippocampal CA1 neurons 4 to 24 h after tGCI. DUSP6-deficient mice showed normal spatial memory acquisition and retention in the Barnes maze. Impairment of spatial memory acquisition and retention after tGCI was attenuated in DUSP6-deficient mice. Neurodegeneration after tGCI, revealed by Fluoro-Jade C and H&E staining, was reduced in the hippocampus of DUSP6-deficient mice and DUSP6 deficiency enhanced the phosphorylation and nuclear translocation of Erk1/2 in the hippocampal CA1 region. These data support the role of DUSP6 as a negative regulator of Erk1/2 signaling and indicate the potential of DUSP6 inhibition as a novel therapeutic strategy to treat neurodegeneration after tGCI.


Brain Ischemia , Ischemic Attack, Transient , Animals , Mice , Brain Ischemia/genetics , CA1 Region, Hippocampal , Cerebral Infarction , Hippocampus , Neurons
4.
FASEB J ; 35(2): e21317, 2021 02.
Article En | MEDLINE | ID: mdl-33421207

Lipocalin-2 (LCN2) has been implicated in promoting apoptosis and neuroinflammation in neurological disorders; however, its role in neural transplantation remains unknown. In this study, we cultured and differentiated Lund human mesencephalic (LUHMES) cells into human dopaminergic-like neurons and found that LCN2 mRNA was progressively induced in mouse brain after the intrastriatal transplantation of human dopaminergic-like neurons. The induction of LCN2 protein was detected in a subset of astrocytes and neutrophils infiltrating the core of the engrafted sites, but not in neurons and microglia. LCN2-immunoreactive astrocytes within the engrafted sites expressed lower levels of A1 and A2 astrocytic markers. Recruitment of microglia, neutrophils, and monocytes after transplantation was attenuated in LCN2 deficiency mice. The expression of M2 microglial markers was significantly elevated and survival of engrafted neurons was markedly improved after transplantation in LCN2 deficiency mice. Brain type organic cation transporter (BOCT), the cell surface receptor for LCN2, was induced in dopaminergic-like neurons after differentiation, and treatment with recombinant LCN2 protein directly induced apoptosis in dopaminergic-like neurons in a dose-dependent manner. Our results, therefore, suggested that LCN2 is a neurotoxic factor for the engrafted neurons and a modulator of neuroinflammation. LCN2 inhibition may be useful in reducing rejection after neural transplantation.


Graft Rejection/metabolism , Lipocalin-2/metabolism , Lipocalin-2/physiology , Neurons/metabolism , Neurons/transplantation , Animals , Apoptosis/genetics , Apoptosis/physiology , Brain/cytology , Brain/metabolism , Cells, Cultured , Flow Cytometry , Graft Rejection/genetics , Humans , Immunohistochemistry , In Situ Nick-End Labeling , Lipocalin-2/genetics , Male , Mice , Mice, Inbred C57BL , Real-Time Polymerase Chain Reaction
5.
Int J Mol Sci ; 21(17)2020 Aug 29.
Article En | MEDLINE | ID: mdl-32872405

Oxidative stress is a key contributor to the pathogenesis of stroke-reperfusion injury. Neuroinflammatory peptides released after ischemic stroke mediate reperfusion injury. Previous studies, including ours, have shown that lipocalin-2 (LCN2) is secreted in response to cerebral ischemia to promote reperfusion injury. Genetic deletion of LCN2 significantly reduces brain injury after stroke, suggesting that LCN2 is a mediator of reperfusion injury and a potential therapeutic target. Immunotherapy has the potential to harness neuroinflammatory responses and provides neuroprotection against stroke. Here we report that LCN2 was induced on the inner surface of cerebral endothelial cells, neutrophils, and astrocytes that gatekeep the blood-brain barrier (BBB) after stroke. LCN2 monoclonal antibody (mAb) specifically targeted LCN2 in vitro and in vivo, attenuating the induction of LCN2 and pro-inflammatory mediators (iNOS, IL-6, CCL2, and CCL9) after stroke. Administration of LCN2 mAb at 4 h after stroke significantly reduced neurological deficits, cerebral infarction, edema, BBB leakage, and infiltration of neutrophils. The binding epitope of LCN2 mAb was mapped to the ß3 and ß4 strands, which are responsible for maintaining the integrity of LCN2 cup-shaped structure. These data indicate that LCN2 can be pharmacologically targeted using a specific mAb to reduce reperfusion injury after stroke.


Antibodies, Monoclonal/administration & dosage , Lipocalin-2/metabolism , Reperfusion Injury/prevention & control , Stroke/drug therapy , Animals , Antibodies, Monoclonal/pharmacology , Astrocytes/metabolism , Blood-Brain Barrier/metabolism , Cerebrum/metabolism , Disease Models, Animal , Epitope Mapping , Lipocalin-2/antagonists & inhibitors , Lipocalin-2/chemistry , Male , Mice , Neutrophils/metabolism , Protein Binding , Protein Structure, Secondary , Reperfusion Injury/etiology , Reperfusion Injury/metabolism , Stroke/complications , Stroke/metabolism
6.
J Microbiol Immunol Infect ; 52(4): 585-591, 2019 Aug.
Article En | MEDLINE | ID: mdl-29150362

BACKGROUND/PURPOSE: Pediculus capitis is the most common human ectoparasite. When it feeds on the blood through the scalp of its host, the anticoagulant in its saliva causes scalp inflammation and itching, and consequent scratching by the host causes further inflammation from bacterial infection. P. capitis infestation is currently a common parasitic dermatosis and a critical public health concern in underdeveloped countries. METHODS: Through naked eye inspection of P. capitis on or in the hair from 323 school children in Cambodia. RESULTS: A total of 143 children (44.3%) were found to have P. capitis infestation. Univariate analysis revealed that girls had a significantly higher infection rate than boys. Overall, young aged schoolchildren (10 yrs old ≤) showed significantly higher infection rate than old aged schoolchildren (>10 yrs old). Groups stratified by time revealed that schoolchildren studied at the afternoon classes than morning classes in Tuol Prum Muoy Primary School had a significantly higher risk in acquisition of P. capitis infestation. Multivariate analysis results indicated that relative to the boys, the girls were at a significantly higher risk of contracting P. capitis infection. When stratified by inspection time with the Tuol Prum Muoy Primary School morning classes as the reference, the Tuol Prum Muoy Primary School afternoon classes exhibited a significantly higher risk of P. capitis infection. CONCLUSION: Primary school children in Cambodia have a high P. capitis infection rate and thus require effective treatment and prevention measures to treat symptoms and lower the infection rate.


Lice Infestations/epidemiology , Pediculus , Adolescent , Age Factors , Animals , Cambodia/epidemiology , Child , Female , Humans , Logistic Models , Male , Multivariate Analysis , Prevalence , Public Health , Risk Factors , Schools , Sex Factors
7.
Am J Trop Med Hyg ; 96(3): 583-588, 2017 03.
Article En | MEDLINE | ID: mdl-28070012

Most intestinal parasitic infections (IPIs), commonly endemic in tropical resource-poor developing countries, are neglected tropical diseases. Parasitic infections and malnutrition are most commonly found in children. We determined the prevalence of IPIs and the risk factors in Battambang Province, northwestern Cambodia, from August to September 2015. This study collected 308 valid questionnaires and specimens from Dontri (173, 56.2%) and Kon Kaêk (135, 43.8%) primary schools. All stool samples were examined using Chang's Feces Examination Apparatus through the merthiolate-iodine-formaldehyde technique. Headache (259, 84.1%), recurrent cough (249, 80.8%), and abdominal pain (235, 76.3%) were the most common symptoms as detected from questionnaire investigation. A total of 155 students were positive for any parasite type; a single parasite type was observed in 97 students (31.5%), two types in 40 students (13.0%), three types in 14 students (4.6%), and four types in four students (1.3%). Nine gastrointestinal parasite species (three helminths and six protozoa) were identified in the stool samples. The most common parasites in schoolchildren were Giardia intestinalis (31.5%) and Entamoeba histolytica/dispar (17.5%). This is the first IPIs study, and more than half of the schoolchildren were infected with parasite species in Moung Russey District of Battambang Province. We found nine parasite species, including helminths and protozoa, and pathogenic protozoa were the main source of IPIs. Improving the detection method, sanitation facilities, and personal hygiene as well as utilizing combined drugs are all important measures to greatly reduce IPIs in Cambodian schoolchildren.


Intestinal Diseases, Parasitic/epidemiology , Adolescent , Animals , Blastocystis/isolation & purification , Cambodia/epidemiology , Child , Cross-Sectional Studies , Entamoeba histolytica/isolation & purification , Feces/parasitology , Female , Giardia lamblia/isolation & purification , Humans , Logistic Models , Male , Multivariate Analysis , Prevalence , Risk Factors , Schools , Students , Surveys and Questionnaires
8.
Data Brief ; 8: 304-7, 2016 Sep.
Article En | MEDLINE | ID: mdl-27331106

This article presents data that were obtained through measuring the impact of the Min oscillation on membrane proteins in Escherichia coli by quantitative protemoics analysis. We isolated inner membranes from the wild-type and mutant strains to generate proteomics datasets based on NanoLC-nanoESI-MS/MS mass spectrometry using the isobaric tags for relative and absolute quantitation (iTRAQ) method. The datasets included the raw spectral files from four sample replicates and the processed files using Proteome Discoverer that contained a total of 40,072 MS/MS spectra with confident peptide identifier (FDR<0.01) and the peak intensity of the reporter ions. The data was further filtered, which resulted in an inner membrane proteome of unique proteins with quantitation. Proteins of interest, that show significant difference in protein abundance of the mutant membrane, were isolated through statistical filtering. The data is related to "Quantitative proteomics analysis reveals the Min system of Escherichia coli modulates reversible protein association with the inner membrane" (Lee et al., 2016 [1]).

9.
Mol Cell Proteomics ; 15(5): 1572-83, 2016 05.
Article En | MEDLINE | ID: mdl-26889046

The Min system of Escherichia coli mediates placement of the division septum at the midcell. It oscillates from pole to pole to establish a concentration gradient of the division inhibition that is high at the poles but low at the midcell; the cell middle thereby becomes the most favorable site for division. Although Min oscillation is well studied from molecular and biophysical perspectives, it is still an enigma as to whether such a continuous, energy-consuming, and organized movement of the Min proteins would affect cellular processes other than the division site selection. To tackle this question, we compared the inner membrane proteome of the wild-type and Δmin strains using a quantitative approach. Forty proteins that showed differential abundance on the inner membrane of the mutant cells were identified and defined as proteins of interest (POIs). More than half of the POIs were peripheral membrane proteins, suggesting that the Min system affects mainly reversible protein association with the inner membrane. In addition, 6 out of 10 selected POIs directly interacted with at least one of the Min proteins, confirming the correlation between POIs and the Min system.Further analysis revealed a functional relationship between metabolism and the Min system. Metabolic enzymes accounted for 45% of the POIs, and there was a change of metabolites in the related reactions. We hypothesize that the Min system could alter the membrane location of proteins to modulate their enzymatic activity. Thus, the metabolic modulation in the Δmin mutant is likely an adaptive phenotype in cells of abnormal size and chromosome number due to an imbalanced abundance of proteins on the inner membrane. Taken together, the current work reports novel interactions of the Min system and reveals a global physiological impact of the Min system in addition to the division site placement.


Cell Membrane/metabolism , Escherichia coli Proteins/genetics , Escherichia coli/metabolism , Proteomics/methods , Cell Division , Escherichia coli/genetics , Escherichia coli Proteins/metabolism , Gene Regulatory Networks , Metabolic Networks and Pathways , Mutation , Protein Interaction Maps
10.
PLoS One ; 10(11): e0142506, 2015.
Article En | MEDLINE | ID: mdl-26562523

Amyloid fibrils play a crucial role in many human diseases and are found to function in a range of physiological processes from bacteria to human. They have also been gaining importance in nanotechnology applications. Understanding the mechanisms behind amyloid formation can help develop strategies towards the prevention of fibrillation processes or create new technological applications. It is thus essential to observe the structures of amyloids and their self-assembly processes at the nanometer-scale resolution under physiological conditions. In this work, we used highly force-sensitive frequency-modulation atomic force microscopy (FM-AFM) to characterize the fibril structures formed by the N-terminal domain of a bacterial division protein MinE in solution. The approach enables us to investigate the fibril morphology and protofibril organization over time progression and in response to changes in ionic strength, molecular crowding, and upon association with different substrate surfaces. In addition to comparison of the fibril structure and behavior of MinE1-31 under varying conditions, the study also broadens our understanding of the versatile behavior of amyloid-substrate surface interactions.


Aluminum Silicates/metabolism , Amyloid/metabolism , Cell Cycle Proteins/metabolism , Escherichia coli Proteins/metabolism , Lipid Bilayers/metabolism , Microscopy, Atomic Force/methods , Aluminum Silicates/chemistry , Amyloid/chemistry , Amyloid/ultrastructure , Cell Cycle Proteins/chemistry , Escherichia coli Proteins/chemistry , Humans , Lipid Bilayers/chemistry , Microscopy, Electron, Transmission , Molecular Dynamics Simulation , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Protein Structure, Secondary , Protein Structure, Tertiary
11.
Eur Neuropsychopharmacol ; 22(10): 695-703, 2012 Oct.
Article En | MEDLINE | ID: mdl-22406240

Methadone, a synthetic racemic opioid that primarily works as a µ-opioid receptor (OPRM1) agonist, is commonly used for the treatment of heroin addiction. Genetic association studies have reported that the OPRM1 gene is involved in the physiology of heroin and alcohol addiction. Our current study is designed to test the hypothesis that genetic polymorphisms in the OPRM1 gene region are associated with methadone dosage, plasma concentrations, treatment responses, adverse reactions and withdrawal symptoms in a methadone maintenance treatment (MMT) cohort from Taiwan. Fifteen OPRM1 single nucleotide polymorphisms (SNPs) were selected and genotyped using DNA samples from 366 MMT patients. The plasma concentrations of methadone and its metabolite were measured by high performance liquid chromatography. The results obtained using dominant model analysis indicate that the OPRM1 SNPs rs1074287, rs6912029, rs12209447, rs510769, rs3798676, rs7748401, rs495491, rs10457090, rs589046, rs3778152, rs563649, and rs2075572 are significantly associated with change-in-libido side effects (adjusted p<0.042). Using recessive model analysis, these SNPs were also found to be significantly associated with insomnia side effects in this cohort (p<0.009). The significance of the insomnia findings was mainly contributed by a subgroup of patients who had a positive urine morphine test (p<0.022), and by individuals who did not use benzodiazepine hypnotics (p<0.034). Our current data thus suggest that genetic polymorphisms in OPRM1 may influence the change-in-libido and insomnia side effects sometimes found in MMT patients.


Analgesics, Opioid/adverse effects , Libido/drug effects , Methadone/adverse effects , Opiate Substitution Treatment , Polymorphism, Single Nucleotide , Receptors, Opioid, mu/genetics , Sleep Initiation and Maintenance Disorders/chemically induced , Adult , Analgesics, Opioid/pharmacokinetics , Analgesics, Opioid/therapeutic use , Benzodiazepines/therapeutic use , Cohort Studies , Cross-Sectional Studies , Female , Genetic Association Studies , Heroin Dependence/blood , Heroin Dependence/drug therapy , Heroin Dependence/metabolism , Heroin Dependence/urine , Humans , Hypnotics and Sedatives/therapeutic use , Male , Methadone/blood , Methadone/pharmacokinetics , Methadone/therapeutic use , Morphine/toxicity , Morphine/urine , Opiate Substitution Treatment/adverse effects , Receptors, Opioid, mu/agonists , Receptors, Opioid, mu/metabolism , Sexual Dysfunctions, Psychological/chemically induced , Sexual Dysfunctions, Psychological/epidemiology , Sexual Dysfunctions, Psychological/genetics , Sleep Initiation and Maintenance Disorders/epidemiology , Sleep Initiation and Maintenance Disorders/genetics , Sleep Initiation and Maintenance Disorders/prevention & control , Substance Abuse Detection , Substance Abuse Treatment Centers , Taiwan/epidemiology
12.
Nanotechnology ; 20(1): 015602, 2009 Jan 07.
Article En | MEDLINE | ID: mdl-19417256

Iron oxide-gold core-shell nanocrystals have been synthesized by the thermal decomposition of iron pentacarbonyl and the subsequent reduction of gold acetate by 1,2-hexadecanediol with oleic acid and oleylamine as stabilizers. Their size, structure, composition, and optical and magnetic properties were characterized. The resultant nanoparticles were nearly monodisperse with a complete core-shell structure, and the shell thickness could be tuned via the seed-mediated growth. Also, they exhibited an absorption band at 520 nm owing to the surface plasmon resonance of Au shells and were nearly superparamagnetic due to the presence of the iron cores. By analyzing the x-ray adsorption near-edge structure (XANES) spectrum and the x-ray photoelectron spectroscopy (XPS) spectra of the fast etching mode, the iron cores were shown to be oxidized but the oxidation was incomplete in the inner region. Noteworthily, the iron oxide-Au nanoparticles could self-assemble into 2D and 3D superlattices. The packing density increased while approaching the center of assembly, leading to the variation of superstructures from a 2D nearly hcp monolayer to a 3D hcp superlattice and a 3D hexagonal superlattice. Moreover, hydrophilic iron oxide-Au core-shell nanoparticles were also obtained by surface modification with mercaptoacetic acid via a phase transfer route.

13.
Clin Chim Acta ; 352(1-2): 209-15, 2005 Feb.
Article En | MEDLINE | ID: mdl-15653116

BACKGROUND: It has been shown that matrix metalloproteinase-9 (MMP-9) is involved in the pathogenesis of various pulmonary inflammatory diseases. We determined the MMP-9 concentration in the plasma of community-acquired pneumonia (CAP) patients before and after antibiotic treatment. METHODS: Gelatin zymography and ELISA analysis were used to measure MMP-9 activity and MMP-9 level, respectively, in 35 control subjects and 46 CAP patients. RESULTS: WBC counts, neutrophils, MMP-9 activity and MMP-9 level were significantly higher in CAP patients compared with that of control subjects (P<0.001), while MMP-9 activity and MMP-9 level were returned to normal after the antibiotic treatment (P<0.001). In addition, MMP-9 level correlated positively with WBC counts and neutrophils number both before and after the antibiotic treatment. CONCLUSIONS: MMP-9 may play an important role in the pathogenesis of CAP with a positive correlation with the number of neutrophils.


Community-Acquired Infections/enzymology , Matrix Metalloproteinase 9/blood , Pneumonia/blood , Pneumonia/enzymology , Adult , Anti-Bacterial Agents/therapeutic use , Community-Acquired Infections/blood , Community-Acquired Infections/drug therapy , Female , Humans , Male , Middle Aged , Pneumonia/drug therapy
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