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1.
Int J Mol Sci ; 24(3)2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36769062

ABSTRACT

We previously demonstrated that the Alzheimer's disease (AD)-like model mice, Tg2576, housed at a high ambient temperature of 30 °C for 13 months, exhibited increased body temperature, which increased amyloid-ß (Aß) levels and tau stability, leading to tau phosphorylation and ultimately inducing memory impairment. Here, we aimed to exclude the possible effect of environmental factors associated with the difference in ambient temperature (23 °C vs. 30 °C) and to further clarify the effects of elevated body temperature on AD-like pathologies. We generated uncoupling protein 1 (UCP1) deletion in Tg2576 mice, Tg2576/UCP1-/-, because UCP1 deletion mice show a sustained rise in body temperature at normal room temperature. As expected, the body temperature in Tg2576/UCP1-/- mice was higher than that in Tg2576/ UCP1+/+ mice at 23 °C, which was accompanied by upregulated Aß levels due to increased ß-secretase (BACE1) and decreased neprilysin (NEP) protein levels in the brains of Tg2576/UCP1-/- mice compared with those in the Tg2576/ UCP1+/+ mice. Elevated body temperature also increased total tau levels, leading to enhanced phosphorylation, heat shock protein induction, and activated tau kinases. Furthermore, elevated body temperature enhanced glial activation and decreased synaptic protein levels in the brain. Taken together, these findings demonstrate that elevated body temperatures exacerbate AD-like pathologies.


Subject(s)
Alzheimer Disease , Mice , Animals , Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/metabolism , Body Temperature , Uncoupling Protein 1/metabolism , Mice, Transgenic , Aspartic Acid Endopeptidases/metabolism , Amyloid beta-Peptides/genetics , Amyloid beta-Peptides/metabolism , Brain/metabolism , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Disease Models, Animal
2.
NPJ Regen Med ; 7(1): 71, 2022 Dec 16.
Article in English | MEDLINE | ID: mdl-36522336

ABSTRACT

Allogeneic cell therapies are not fully effective in treating osteoarthritis of the knee (OAK). We recently reported that transplantation of autologous chondrocyte cell-sheets along with open-wedge high tibial osteotomy promoted hyaline cartilage repair in humans. Here we describe our regenerative therapy for OAK using polydactyly-derived allogeneic chondrocyte cell-sheets (PD sheets) and temperature-responsive culture inserts. Ten patients with OAK and cartilage defects categorized arthroscopically as Outerbridge grade III or IV received the therapy. Cartilage viscoelasticity and thickness were assessed before and after transplantation. Arthroscopic biopsies obtained 12 months after transplantation were analyzed histologically. Gene expression was analyzed to evaluate the PD sheets. In this small initial longitudinal series, PD sheet transplantation was effective in treating OAK, as indicated by changes in cartilage properties. Gene marker sets in PD sheets may predict outcomes after therapy and provide markers for the selection of donor cells. This combined surgery may be an ideal regenerative therapy with disease-modifying effects in OAK patients.

3.
Sci Rep ; 12(1): 12273, 2022 07 18.
Article in English | MEDLINE | ID: mdl-35851831

ABSTRACT

Global warming is a serious public health threat to people worldwide. High body temperature is one of the important risk factors for Alzheimer's disease (AD), and the body temperature of AD patients has been found to be significantly higher than that of elderly control subjects. However, the effects of high body temperature on cognitive function and AD pathologies have not been completely elucidated. We report here that Tg2576 mice housed at a high ambient temperature of 30 °C for 13 months showed an increase in the body temperature, which is accompanied by memory impairment and an enhancement of amyloid-ß peptides (Aß) generation through the upregulation of ß-site APP cleaving enzyme 1 (BACE1) level and decrease in the level of an Aß-degrading enzyme, neprilysin (NEP) in the brain, compared with those of Tg2576 mice at 23 °C. High body temperature also increased the levels of heat shock proteins (HSPs), stress-stimulated kinases such as JNK, and total tau, leading to the enhancement of tau phosphorylation at 30 °C. Taken together, our findings suggest that high body temperature exacerbates cognitive function and AD pathologies, which provides a mechanistic insight for its prevention.


Subject(s)
Alzheimer Disease , Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Animals , Aspartic Acid Endopeptidases/metabolism , Body Temperature , Brain/metabolism , Cognition , Disease Models, Animal , Humans , Mice , Mice, Transgenic
4.
J Toxicol Sci ; 47(4): 151-157, 2022.
Article in English | MEDLINE | ID: mdl-35370243

ABSTRACT

The effect of nanoparticle type, shape, as well as primary and secondary particle size on toxicity remains poorly characterized. In this study, suspensions of nickel oxide (NiO) nanoparticles with the same primary particle size (< 50 nm) but different secondary particle sizes were prepared, and their cytotoxicity was investigated. A planetary ball mill wet nanopulverizer with zirconium milling balls of decreasing sizes (φ: 0.5, 0.1, and 0.05 mm) yielded NiO nanoparticles of decreasing mean particle size (310.4 ± 6.7, 172.0 ± 2.8, and 102.0 ± 0.5 nm). Stock solutions were diluted to various concentrations in 10% heat-inactivated fetal bovine serum containing minimum essential medium, and shown to have the same primary particle size, but different secondary particle sizes. Tests with A549 cells revealed that cytotoxicity increased with increasing secondary particle size: milling ball diameter φ 0.05 mm (IC50: 148 µg/mL) < φ 0.1 mm (IC50: 83.5 µg/mL) < φ 0.5 mm (IC50: 33.4 µg/mL). Uptake experiments indicated that the intracellular amount of Ni increased with increasing secondary particle size. In summary, the present findings show that differences in secondary particle size affected the cytotoxicity of NiO suspensions, which could be ascribed at least in part to differences in the amount of NiO taken up by the cells.


Subject(s)
Nanoparticles , Nickel , A549 Cells , Humans , Nanoparticles/toxicity , Nickel/toxicity , Particle Size
5.
BMC Pediatr ; 21(1): 265, 2021 06 05.
Article in English | MEDLINE | ID: mdl-34090356

ABSTRACT

BACKGROUND: Spontaneous infection of preexisting solitary renal cysts has been documented in adults but is extremely rare in children. To date, no cases of simple renal cysts infected with Streptococcus pneumoniae have been described. Recently, reports have described the diagnosis of bacterial infection using the 16 S rRNA gene as well as the accompanying antimicrobial stewardship for microorganisms that are difficult to culture and for culture-negative cases after preceding antibacterial administration. CASE PRESENTATION: A four-year-old Japanese girl who had a pleuroperitoneal shunt inserted to drain a right pleural effusion due to occlusion of the hepatic portion of the inferior vena cava at three years old visited our hospital due to fever and respiratory discomfort. She was incidentally found to have a right simple renal cyst 10 months before admission. The patient was suspected to have pneumonitis or catheter-related blood stream infection on chest X-ray, which showed right-side pleural effusion. She was diagnosed with invasive pneumococcal infection, as Streptococcus pneumoniae was detected from blood culture on admission. Transient improvements in her symptoms and decreases in the white blood cell count and C-reactive protein level were observed after effective antibiotic administration, but her respiratory condition deteriorated. Enhanced CT showed right renal cyst enlargement and enhancement and thickening of the surrounding wall. Using the melting temperature (Tm) mapping method, S. pneumoniae was rapidly detected directly from pus 4.5 hours after drainage. The specimen culture was negative, but the extracted 16 S rDNA sequence revealed 100 % identity for S. pneumoniae from the same specimen the subsequent day. We successfully performed optimal treatment and reduced medical cost based on the positive Tm mapping method result. CONCLUSIONS: We report the first case of a S. pneumoniae-infected simple renal cyst. The drainage culture was negative, but the Tm mapping method rapidly detected S. pneumoniae directly from the drainage. The Tm mapping method may have great impacts on rapid diagnosis and effective antimicrobial stewardship.


Subject(s)
Kidney Diseases, Cystic , Pleural Effusion , Pneumococcal Infections , Adult , Child , Child, Preschool , Female , Humans , Pneumococcal Infections/complications , Pneumococcal Infections/diagnosis , Pneumococcal Infections/drug therapy , Streptococcus pneumoniae/genetics , Thermography
6.
Toxicol In Vitro ; 68: 104919, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32645342

ABSTRACT

In biological safety evaluation of medical devices, false-negative results have been observed during skin irritation testing using the reconstructed human epidermis (RhE) model when measuring cell viability as a single marker. Therefore, to improve testing accuracy, this study conducted a comprehensive survey and performance evaluation of cytokines to identify a second marker. In addition to IL-1α, macrophage migration inhibitory factor (MIF) was newly identified as a candidate marker, in the Bio-Plex assay of EpiDerm model exposed to polymer sample extracts. Irritation based on cell viability level was not accurately determined in LabCyte model using silicone spiked with 25% heptanoic acid (HA). By contrast, the irritation potency was accurately assessed in detail by measuring IL-1α or MIF. Further, IL-1α and MIF levels in EpiDerm, LabCyte, and EpiSkin models stimulated with sodium dodecyl sulfate (SDS) were inversely correlated with cell viability, and were detected even at low SDS concentrations without cell toxicity. Additionally, MIF demonstrated greater S/N ratio and dose-dependency at high SDS concentrations in some models compared to IL-1α. These results indicated that MIF might be a useful second marker for improving the sensitivity and accuracy of skin irritation testing with RhE models.


Subject(s)
Cytokines/metabolism , Epidermis/drug effects , Equipment and Supplies/adverse effects , Irritants/toxicity , Skin Irritancy Tests , Biomarkers/metabolism , Epidermis/metabolism , Humans , Models, Biological , Polymers/toxicity
7.
J Infect Chemother ; 26(9): 882-889, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32591324

ABSTRACT

We report on the findings of the first antimicrobial susceptibility surveillance study in Japan of isolates recovered from odontogenic infections. Of the 38 facilities where patients representing the 4 groups of odontogenic infections were seen, 102 samples were collected from cases of periodontitis (group 1), 6 samples from pericoronitis (group 2), 84 samples from jaw inflammation (group 3) and 54 samples from phlegmon of the jaw bone area (group 4) for a total of 246 samples. The positivity rates of bacterial growth on culture were 85.3%, 100%, 84% and 88.9%, respectively, for groups 1, 2, 3 and 4. Streptococcus spp. isolation rates according to odontogenic infection group were 22% (group 1), 17.7% (group 3) and 20.7% (group 4). Anaerobic isolation rates were 66.9% (group 1), 71.8% (group 3) and 68.2% (group 4). Drug susceptibility tests were performed on 726 strains excluding 121 strains that were undergrown. The breakdown of the strains subjected to testing was 186 Streptococcus spp., 179 anaerobic gram-positive cocci, 246 Prevotella spp., 27 Porphyromonas spp., and 88 Fusobacterium spp. The isolates were tested against 30 antimicrobial agents. Sensitivities to penicillins and cephems were good except for Prevotella spp. The low sensitivities of Prevotella spp is due to ß-lactamase production. Prevotella strains resistant to macrolides, quinolones, and clindamycin were found. No strains resistant to carbapenems or penems were found among all strains tested. No anaerobic bacterial strain was resistant to metronidazole. Antimicrobial susceptibility testing performed on the S. anginosus group and anaerobic bacteria, which are the major pathogens associated with odontogenic infections, showed low MIC90 values to the penicillins which are the first-line antimicrobial agents for odontogenic infections; however, for Prevotella spp., penicillins combined with ß-lactamase inhibitor showed low MIC90 values.


Subject(s)
Anti-Bacterial Agents , Bacterial Infections , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacteria, Anaerobic , Bacterial Infections/drug therapy , Bacterial Infections/epidemiology , Clindamycin/pharmacology , Clindamycin/therapeutic use , Drug Resistance, Bacterial , Humans , Japan/epidemiology , Microbial Sensitivity Tests , Penicillins
8.
J Vet Med Sci ; 82(6): 740-744, 2020 Jun 16.
Article in English | MEDLINE | ID: mdl-32295988

ABSTRACT

A twenty-year-old male Asiatic black bear (Ursus thibetanus) presented at the Rakuno Gakuen University Animal Medical Center with a 10-year history of bilateral blindness and cataracts. Surgical treatment of bilateral cataracts by extracapsular lensextraction using phacoemulsification and aspiration (PEA) was performed under general anesthesia. An anterior capsulectomy was performed using micro iris scissors and micro anterior lens capsule forceps. The cataract was removed with PEA using the two-handed technique. After surgery, systemic corticosteroids, anti-inflammatory drugs and antibiotics were administered. After cataract removal, the bear had recovered vision, and good quality vision has been maintained to date (15 months). PEA can be a safe and effective treatment for cataracts that impair vision in bears.


Subject(s)
Cataract/veterinary , Phacoemulsification/veterinary , Ursidae/surgery , Animals , Male
9.
Shokuhin Eiseigaku Zasshi ; 60(5): 144-150, 2019.
Article in Japanese | MEDLINE | ID: mdl-31956240

ABSTRACT

Qualitative real-time PCR method for three poisonous Entoloma rhodopolium-related species in Japan was established using specific primers and FAM, VIC, Texas Red, Cy5-labeled probes. The use of multicolor probes can extend the method to simultaneous detection of different targets. Standard plasmids were constructed as reference materials. Designed primers and probes in the method detect only a target species, and the detection limit was 12.5 copies or below. This indicates it is highly specific and sensitive enough to detect the poisonous mushrooms in food residues. Next, we applied the method to four food residue samples obtained from food poisoning cases. The real-time PCR method did identify all of four samples as E. subrhodopolium and E. pseudorhodopolium, whereas PCR-RFLP did not. The method established here revealed Entoloma rhodopolium-related species in Hokkaido were different species such as E. eminens and unknown species.


Subject(s)
Agaricales/classification , Food Analysis/methods , Real-Time Polymerase Chain Reaction , DNA Primers , Japan , Mushroom Poisoning , Sensitivity and Specificity
10.
J Ultrasound Med ; 38(4): 1109-1113, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30346045

ABSTRACT

This report describes the evaluations of 2 patients with congenital diaphragmatic hernias using ultrasound (US). Identifying the size of the diaphragmatic defect is important when determining the type of surgical repair required. In case 1, the US evaluation of a Bochdalek hernia showed the rim of the anterolateral diaphragm; therefore, thoracoscopic primary repair was performed. In case 2, (Morgagni-Larrey hernia), US revealed the left side of a retrosternal diaphragmatic hernia sac; therefore, thoracoscopic repair from the left thorax was performed. Ultrasound was useful for detecting the location and defect size of the diaphragmatic hernia and determining optimal surgical management.


Subject(s)
Hernias, Diaphragmatic, Congenital/diagnostic imaging , Ultrasonography/methods , Diaphragm/diagnostic imaging , Diaphragm/surgery , Hernias, Diaphragmatic, Congenital/surgery , Humans , Infant , Infant, Newborn , Male
12.
Eye Contact Lens ; 44 Suppl 2: S105-S112, 2018 Nov.
Article in English | MEDLINE | ID: mdl-28953599

ABSTRACT

OBJECTIVES: This study evaluates pigment component distribution and depth in decorative soft contact lenses (DSCLs) using a variety of analytical methods. METHODS: We sampled 18 DSCLs using optical microscopy, optical coherence tomography analysis, Z-stack analysis, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX), and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to evaluate the distribution and depth of pigment components. RESULTS: Pigment distribution in DSCLs was easily observed with optical methods including Z-stack analysis. X-ray photoelectron spectroscopy, SEM/EDX, and TOF-SIMS were used to evaluate the level of pigment exposure on the lens surface and the results showed significant differences between the methods. Pigment components were detected in 16 samples by SEM/EDX, but not by XPS. Pigment components were only detected in eight samples using TOF-SIMS. CONCLUSIONS: It may be necessary to show that a nanometer-thick monomolecular film does not exist on the surface of DSCLs, to demonstrate the exposure of a pigment particle. Taking into account the principle behind each of the measurement methods and the resolution and sensitivity of each of the analytical methods compared, TOF-SIMS may be the most appropriate method to accurately judge pigment exposure on DSCLs. The Z-stack method may be useful for estimating the depth of pigment components in DSCLs.


Subject(s)
Coloring Agents/analysis , Contact Lenses, Hydrophilic , Microscopy, Electron, Scanning/methods , Spectrometry, Mass, Secondary Ion/methods , Spectrometry, X-Ray Emission/methods , Surface Properties
13.
Plast Reconstr Surg Glob Open ; 5(9): e1501, 2017 Sep.
Article in English | MEDLINE | ID: mdl-29062665

ABSTRACT

BACKGROUND: A lymphangioma, also called a lymphatic malformation, is a congenital condition that frequently occurs in young children. It is classified into 3 groups depending on the size of the cysts (macrocystic, microcystic, and mixed). Spontaneous regression occurs in some cases; however, the characteristics of patients who show regression have not been studied previously. Furthermore, the types and the timing of the initial treatment are still controversial. Therefore, we statistically analyzed the occurrence of short-term spontaneous regression, patient age at original occurrence, cyst types, cyst sizes, and cyst locations in patients diagnosed with peripheral localized lymphangiomas in a single children center over 34 years. METHODS: We retrospectively collected the data of 153 patients and reviewed the medical charts. RESULTS: Spontaneous regression occurred only in macrocystic or mixed type; regression was most frequent in patients who, at the time of onset, were more than 2 years old. CONCLUSIONS: We concluded that elderly patients with macrocystic or mixed type lymphangioma may have to wait for treatment for over 3 months from the initial onset. Conversely, microcystic type could not be expected to show regression in a short period, and prompt initiation of the treatments may be required. The difference of the regression or not may depend on the characteristics of the lymph flow.

14.
J Hum Genet ; 62(11): 945-948, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28680109

ABSTRACT

Fukuyama congenital muscular dystrophy (FCMD), which is caused by mutations in the fukutin gene, is the second most common form of childhood muscular dystrophy in Japan. The founder haplotype is the most prevalent in the chromosomes of Japanese FCMD patients, and corresponds to an SVA retrotransposal insertion in the 3'-untranslated region of fukutin. Although other mutations have been reported, the mutation corresponding to the second most prevalent haplotype in Japanese FCMD patients remained unknown. Recently a deep-intronic point mutation c.647+2084G>T was identified in Korean patients with congenital muscular dystrophy. Here, we performed mutational analysis of 10 patients with the second most prevalent haplotype and found that all of them were compound-heterozygous for the SVA insertion and this c.647+2084G>T mutation. The fukutin mRNA of these patients contained a pseudoexon between exon 5 and exon 6, which was consistent with the previous Korean study. As expected, the mutated fukutin protein was smaller than the normal protein, reflecting the truncation of fukutin due to a premature stop codon. Immunostaining analysis showed a decrease in the signal for the glycosylated form of α-dystroglycan. These findings indicated that this mutation is the second most prevalent loss-of-function mutation in Japanese FCMD patients.


Subject(s)
Membrane Proteins/genetics , Walker-Warburg Syndrome/epidemiology , Walker-Warburg Syndrome/genetics , DNA Mutational Analysis/methods , Exons/genetics , Female , Haplotypes/genetics , Humans , Introns/genetics , Japan/epidemiology , Male , Point Mutation , Walker-Warburg Syndrome/pathology
15.
PLoS One ; 11(5): e0155400, 2016.
Article in English | MEDLINE | ID: mdl-27196068

ABSTRACT

ATP-binding cassette G1 (ABCG1) and ABCG4, expressed in neurons and glia in the central nervous system, mediate cholesterol efflux to lipid acceptors. The relationship between cholesterol level in the central nervous system and Alzheimer's disease has been reported. In this study, we examined the effects of ABCG1 and ABCG4 on amyloid precursor protein (APP) processing, the product of which, amyloid ß (Aß), is involved in the pathogenesis of Alzheimer's disease. Expression of ABCG1 or ABCG4 in human embryonic kidney 293 cells that stably expressed Swedish-type mutant APP increased cellular and cell surface APP levels. Products of cleavage from APP by α-secretase and by ß-secretase also increased. The levels of secreted Aß, however, decreased in the presence of ABCG1 and ABCG4, but not ABCG4-KM, a nonfunctional Walker-A lysine mutant. In contrast, secreted Aß levels increased in differentiated SH-SY5Y neuron-like cells in which ABCG1 and ABCG4 were suppressed. Furthermore, Aß42 peptide in the cerebrospinal fluid from Abcg1 null mice significantly increased compared to the wild type mice. To examine the underlying mechanism, we analyzed the activity and distribution of γ-secretase. ABCG1 and ABCG4 suppressed γ-secretase activity and disturbed γ-secretase localization in the raft domains where γ-secretase functions. These results suggest that ABCG1 and ABCG4 alter the distribution of γ-secretase on the plasma membrane, leading to the decreased γ-secretase activity and suppressed Aß secretion. ABCG1 and ABCG4 may inhibit the development of Alzheimer's disease and can be targets for the treatment of Alzheimer's disease.


Subject(s)
ATP Binding Cassette Transporter, Subfamily G, Member 1/metabolism , ATP Binding Cassette Transporter, Subfamily G/metabolism , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/biosynthesis , ATP Binding Cassette Transporter, Subfamily G/genetics , ATP Binding Cassette Transporter, Subfamily G, Member 1/genetics , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/genetics , Animals , Caveolin 1/metabolism , Cell Line, Tumor , Cell Membrane/metabolism , Gene Silencing , HEK293 Cells , Humans , Lysine , Membrane Glycoproteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Mutation , RNA Interference
16.
Article in Japanese | MEDLINE | ID: mdl-26821468

ABSTRACT

To investigate relationships between particle (as a model of aggregates) size in a nanomaterial test suspension and its cytotoxicity, a series of eleven sizes of polystyrene (PS) particles were tested in the cytotoxicity test and the chromosome aberration test by using a Chinese hamster cell line CHL. The PS particles were spheres with defined diameters ranging from 0.1 to 9.2 µm. A series of eight sizes of particles with diameters ranging from 0.92 to 4.45 µm showed stronger cytotoxicity than the others. There was a marked difference in cytotoxicity between the 4.45- and 5.26-µm particles. The 0.92- to 4.45-µm particles did not induce structural chromosome aberrations but induced a high frequency of polyploidy in the chromosome aberration test. The 5.26-µm particles showed very weak induction of polyploidy. The incorporation of the 4.45-µm particles into CHL cells was observed by scanning electron microscopy (SEM). Some cells incorporated more than 10 particles. The semi-quantitative measurement of incorporation of particles into cells was performed by flow cytometry with a parameter of side scattered light (SSC) intensity. It showed that CHL cells preferably incorporated the 4.45-µm particles to the 5.26-µm particles. These findings suggest that CHL cells may have a kind of size-recognition ability and incorporate a particular size of particles. The particles may prevent a normal cytokinesis resulting in polyploidy induction. Nanomaterials also may show size-dependent toxicity. Data on particle (or aggregate) size distribution in the test suspension should be provided to evaluate properly the results of toxicity tests of nanomaterials.


Subject(s)
Aneugens/toxicity , Fibroblasts/drug effects , Particle Size , Polyploidy , Polystyrenes/toxicity , Aneugens/metabolism , Animals , Cell Line , Chromosome Aberrations/drug effects , Cricetinae , Cricetulus , Fibroblasts/cytology , Fibroblasts/metabolism , Mutagenicity Tests , Nanostructures , Polystyrenes/metabolism
17.
PLoS One ; 9(10): e109886, 2014.
Article in English | MEDLINE | ID: mdl-25302608

ABSTRACT

ATP-binding cassette A1 (ABCA1), ABCG1, and ABCG4 are lipid transporters that mediate the efflux of cholesterol from cells. To analyze the characteristics of these lipid transporters, we examined and compared their distributions and lipid efflux activity on the plasma membrane. The efflux of cholesterol mediated by ABCA1 and ABCG1, but not ABCG4, was affected by a reduction of cellular sphingomyelin levels. Detergent solubility and gradient density ultracentrifugation assays indicated that ABCA1, ABCG1, and ABCG4 were distributed to domains that were solubilized by Triton X-100 and Brij 96, resistant to Triton X-100 and Brij 96, and solubilized by Triton X-100 but resistant to Brij 96, respectively. Furthermore, ABCG1, but not ABCG4, was colocalized with flotillin-1 on the plasma membrane. The amounts of cholesterol extracted by methyl-ß-cyclodextrin were increased by ABCA1, ABCG1, or ABCG4, suggesting that cholesterol in non-raft domains was increased. Furthermore, ABCG1 and ABCG4 disturbed the localization of caveolin-1 to the detergent-resistant domains and the binding of cholera toxin subunit B to the plasma membrane. These results suggest that ABCA1, ABCG1, and ABCG4 are localized to distinct membrane meso-domains and disturb the meso-domain structures by reorganizing lipids on the plasma membrane; collectively, these observations may explain the different substrate profiles and lipid efflux roles of these transporters.


Subject(s)
ATP Binding Cassette Transporter 1/metabolism , ATP-Binding Cassette Transporters/metabolism , Cell Membrane/metabolism , Membrane Lipids/metabolism , ATP Binding Cassette Transporter, Subfamily G , ATP Binding Cassette Transporter, Subfamily G, Member 1 , Cell Line, Tumor , Cell Membrane/drug effects , Cholesterol/metabolism , Detergents/pharmacology , HEK293 Cells , Humans , Membrane Proteins/metabolism , Octoxynol/pharmacology , Organ Specificity
18.
Clin Chim Acta ; 421: 147-51, 2013 Jun 05.
Article in English | MEDLINE | ID: mdl-23523588

ABSTRACT

BACKGROUND: Although a defect in ADAMTS13 activity is known to cause platelet thrombosis resulting in thrombotic thrombocytopenic purpura (TTP), recent evidence has revealed that low plasma ADAMTS13 concentrations may increase the risk of ischemic vascular diseases. Furthermore, reduced plasma ADAMTS13 activity has been reported in acute systemic inflammation or sepsis. These findings prompted us to examine whether ADAMTS13 may play a role in more diverse diseases, not limited to TTP. METHODS: A cross-sectional study was conducted to examine ADAMTS13 concentrations in blood samples from 432 subjects who had undergone a general health examination. RESULTS: Serum ADAMTS 13 concentrations were lower in men than in women and in older age, as previously reported. Of note, the serum ADAMTS13 concentration was significantly and inversely correlated with the systolic blood pressure, pulse pressure, and serum C reactive protein concentration in both men and women and with the serum γ-glutamyltransferase concentration in men only. In 88 subjects, who underwent a carotid artery evaluation, serum ADAMTS13 concentrations were significantly lower in the subjects with a thicker carotid intima-media. CONCLUSIONS: ADAMTS13 may play a role in not only TTP, but also inflammation, oxidative stress, and atherosclerosis. The potentially diverse clinical significance of ADAMTS13 should be prospectively elucidated in a larger cohort.


Subject(s)
ADAM Proteins/blood , Blood Pressure/physiology , ADAMTS13 Protein , Age Factors , Aged , Analysis of Variance , C-Reactive Protein/analysis , Carotid Intima-Media Thickness , Cross-Sectional Studies , Female , Health Status , Humans , Japan , Male , Mass Screening , Middle Aged , Pulse , Sex Factors , gamma-Glutamyltransferase/blood
19.
Int J Biomater ; 2011: 424571, 2011.
Article in English | MEDLINE | ID: mdl-21826143

ABSTRACT

Currently, nonanimal methods of skin sensitization testing for various chemicals, biodegradable polymers, and biomaterials are being developed in the hope of eliminating the use of animals. The human cell line activation test (h-CLAT) is a skin sensitization assessment that mimics the functions of dendritic cells (DCs). DCs are specialized antigen-presenting cells, and they interact with T cells and B cells to initiate immune responses. Phenotypic changes in DCs, such as the production of CD86 and CD54 and internalization of MHC class II molecules, have become focal points of the skin sensitization test. In this study, we used h-CLAT to assess the effects of biodegradable polymers. The results showed that several biodegradable polymers increased the expression of CD54, and the relative skin sensitizing abilities of biodegradable polymers were PLLG (75 : 25) < PLLC (40 : 60) < PLGA (50 : 50) < PCG (50 : 50). These results may contribute to the creation of new guidelines for the use of biodegradable polymers in scaffolds or allergenic hazards.

20.
Genes Cells ; 16(7): 803-14, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21668589

ABSTRACT

The protein known as Spred1 (Sprouty-related Ena/VASP homology-1 domain-containing protein) has been identified as a negative regulator of growth factor-induced ERK/mitogen-activated protein kinase activation. Spred1 has also been implicated as the target of microRNA-126 (miR126), a miRNA located within the Egfl7 gene, and is involved in the regulation of vessel development through its role in regulating VEGF signaling. In this study, we examined the role of miR126 and Spred1 in the hematopoietic system, as miR126 has been shown to be overexpressed in leukemic cells. miR126 levels were down-regulated during mast cell differentiation from bone marrow cells, whereas Spred1 expression was inversely up-regulated. Overexpression of miR126 suppressed Spred1 expression and enhanced ERK activity in primary bone marrow cells and MC9 mast cells, which were associated with elevated FcεRI-mediated cytokine production. To confirm the effect of Spred1 reduction in vivo, we generated hematopoietic cell-specific Spred1-conditional knockout mice. These mice showed increased numbers of mast cells, and Spred1-deficient bone marrow-derived mast cells were highly activated by cross-linking of Fcε-R stimulation as well as by IL-3 and SCF stimulation. These results suggest that Spred1 negatively regulates mast cell activation, which is modulated by miR126.


Subject(s)
Cytokines/biosynthesis , Mast Cells/cytology , Mast Cells/metabolism , MicroRNAs/genetics , Repressor Proteins/deficiency , Repressor Proteins/genetics , Adaptor Proteins, Signal Transducing , Animals , Cell Proliferation , Cells, Cultured , HEK293 Cells , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout
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