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1.
Arthritis Res Ther ; 22(1): 72, 2020 04 07.
Article in English | MEDLINE | ID: mdl-32264967

ABSTRACT

BACKGROUND: Relapses frequently occur in giant cell arteritis (GCA), and long-term glucocorticoid therapy is required. The identification of associated factors with poor treatment outcomes is important to decide the treatment algorithm of GCA. METHODS: We enrolled 139 newly diagnosed GCA patients treated with glucocorticoids between 2007 and 2014 in a retrospective, multi-center registry. Patients were diagnosed with temporal artery biopsy, 1990 American College of Rheumatology classification criteria, or large vessel lesions (LVLs) detected by imaging based on the modified classification criteria. Poor treatment outcomes (non-achievement of clinical remission by week 24 or relapse during 52 weeks) were evaluated. Clinical remission was defined as the absence of clinical signs and symptoms in cranial and large vessel areas, polymyalgia rheumatica (PMR), and elevation of C-reactive protein (CRP) levels. A patient was determined to have a relapse if he/she had either one of the signs and symptoms that newly appeared or worsened after achieving clinical remission. Re-elevation of CRP without clinical manifestations was considered as a relapse if other causes such as infection were excluded and the treatment was intensified. Associated factors with poor treatment outcomes were analyzed by using the Cox proportional hazard model. RESULTS: Cranial lesions, PMR, and LVLs were detected in 77.7%, 41.7%, and 52.5% of the enrolled patients, respectively. Treatment outcomes were evaluated in 119 newly diagnosed patients who were observed for 24 weeks or longer. The mean initial dose of prednisolone was 0.76 mg/kg/day, and 29.4% received any concomitant immunosuppressive drugs at baseline. Overall, 41 (34.5%) of the 119 patients had poor treatment outcomes; 13 did not achieve clinical remission by week 24, and 28 had a relapse after achieving clinical remission. Cumulative rates of the events of poor treatment outcomes in patients with and without LVLs were 47.5% and 17.7%, respectively. A multivariable model showed the presence of LVLs at baseline was significantly associated with poor treatment outcomes (adjusted hazard ratio [HR] 3.54, 95% CI 1.52-8.24, p = 0.003). Cranial lesions and PMR did not increase the risk of poor treatment outcomes. CONCLUSION: The initial treatment intensity in the treatment algorithm of GCA could be determined based upon the presence or absence of LVLs detected by imaging at baseline.


Subject(s)
Giant Cell Arteritis/drug therapy , Glucocorticoids/therapeutic use , Outcome Assessment, Health Care/statistics & numerical data , Adult , Aged , Aged, 80 and over , C-Reactive Protein/analysis , Female , Giant Cell Arteritis/diagnosis , Humans , Male , Middle Aged , Multivariate Analysis , Outcome Assessment, Health Care/methods , Proportional Hazards Models , Recurrence , Remission Induction , Retrospective Studies , Risk Factors
2.
FEBS Open Bio ; 8(5): 799-816, 2018 May.
Article in English | MEDLINE | ID: mdl-29744294

ABSTRACT

5-Hydroxy-3-methylglutaryl-CoA reductase inhibitors (statins) have beneficial effects in patients with heart failure (HF), regardless of serum cholesterol levels. However, their synergic effects with angiotensin II receptor blocker (ARB) remain to be established. We assessed the existence and potential underlying mechanisms of the effects of combined ARB [losartan (LOS)] and statin [simvastatin (SIM)] on cardiac function in rats and mice with load-induced HF. Salt-loaded Dahl salt-sensitive (DS) rats were treated with vehicle, LOS, SIM, or LOS + SIM for 8 weeks. To mimic load-induced HF in vitro, cultured neonatal rat cardiomyocytes (NRCM) were cyclically stretched. We also investigated the effect of LOS + SIM on pressure overload-induced HF using mice with transverse aortic constriction (TAC). LOS + SIM improved left ventricular (LV) function and reduced LV hypertrophy more than the monotherapies in both salt-loaded DS rats and TAC-operated mice. LV-tissue increases in Rho kinase and matrix metalloproteinase-9 activity were decreased to a greater extent by LOS + SIM than by LOS and SIM monotherapies. Plasma levels of Exp-3174, a LOS metabolite, were higher in LOS + SIM-treated DS rats than in LOS-treated rats. Stretch-induced hypertrophy of NRCM pretreated with SIM + Exp-3174 was significantly attenuated from that with LOS, Exp-3174, SIM, or LOS + SIM. SIM administration significantly enhanced mitophagy in mouse hearts after TAC. However, LOS + SIM reduced mitophagy, and the salutary effect of SIM in mouse hearts after TAC was abolished in AT1R-/- mice. In conclusion, LOS and SIM have beneficial myocardial effects on load-induced HF via differential pleiotropic effects. Thus, combination therapy of these drugs thus has potential as a therapeutic strategy for HF.

3.
Circ Res ; 117(6): 502-512, 2015 Aug 28.
Article in English | MEDLINE | ID: mdl-26199323

ABSTRACT

RATIONALE: The development of molecular imaging approaches that assess specific immunopathologic mechanisms can advance the study of myocarditis. OBJECTIVE: This study validates a novel molecular imaging tool that enables the in vivo visualization of granzyme B activity, a major effector of cytotoxic CD8+ T lymphocytes. METHODS AND RESULTS: We synthesized and optimized a fluorogenic substrate capable of reporting on granzyme B activity and examined its specificity ex vivo in mice hearts with experimental cytotoxic CD8+ T lymphocyte-mediated myocarditis using fluorescence reflectance imaging, validated by histological examination. In vivo experiments localized granzyme B activity in hearts with acute myocarditis monitored by fluorescent molecular tomography in conjunction with coregistered computed tomography imaging. A model anti-inflammatory intervention (dexamethasone administration) in vivo reduced granzyme B activity (vehicle versus dexamethasone: 504±263 versus 194±77 fluorescence intensities in hearts; P=0.002). CONCLUSIONS: Molecular imaging of granzyme B activity can visualize T cell-mediated myocardial injury and monitor the response to an anti-inflammatory intervention.


Subject(s)
Granzymes/metabolism , Myocarditis/enzymology , Myocarditis/immunology , Animals , CD8-Positive T-Lymphocytes/enzymology , CD8-Positive T-Lymphocytes/immunology , Enzyme Activation/physiology , Fluorescent Dyes/analysis , Granzymes/analysis , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Myocarditis/pathology
4.
J Card Fail ; 18(8): 620-5, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22858077

ABSTRACT

BACKGROUND: Although hyponatremia during hospitalization for acute decompensated heart failure (ADHF) has been reported to correlate with poor prognosis, few studies have examined the effect of progression of hyponatremia on cardiac prognosis in ADHF patients who were normonatremic at admission. METHODS AND RESULTS: Consecutive ADHF patients (n = 662) categorized as New York Heart Association Class III or IV were investigated retrospectively. Of these patients, 634 who survived to discharge were examined and 531 were normonatremic (serum sodium concentration [Na] ≥ 135 and ≤ 145 mmol/L) at admission. The 531 patients were divided into 2 groups: the non-developed group, who remained normonatremic at discharge (n = 455), and the developed group, who had progressed to hyponatremia (Na < 135 mmol/L) at discharge (n = 76). The cardiac event-free rate after 12 months was significantly lower in the developed group than in the non-developed group (22% vs. 71%; P < .0001). Although their baseline levels of brain natriuretic peptide and left ventricular ejection fraction were similar before discharge, the patients in the developed group exhibited higher fractional excretion of sodium and received higher doses of diuretics than did those in the non-developed group. CONCLUSION: Our data suggest that progression to hyponatremia during hospitalization is a robust predictor of poor cardiac prognosis in ADHF patients who were normonatremic at admission.


Subject(s)
Disease Progression , Heart Failure/mortality , Hospitalization , Hyponatremia/pathology , Aged , Confidence Intervals , Diuretics/therapeutic use , Female , Heart Failure/drug therapy , Heart Failure/pathology , Humans , Hyponatremia/complications , Japan , Male , Natriuretic Peptide, Brain , Prognosis , Retrospective Studies , Stroke Volume , Ventricular Function, Left
5.
ISRN Pharm ; 2012: 125864, 2012.
Article in English | MEDLINE | ID: mdl-22500243

ABSTRACT

ß-Glucans extracted from barley, which mainly contains ß-(1,3-1,4)-D-glucan, are used extensively as supplements and food additives due to their wide biologic activities, including a reduction in blood lipid level. In this study, the antioxidant activity of ß-glucan was examined to assess potential new benefits associated with ß-glucan, because oxidative stress is considered one of the primary causal factors for various diseases and aging. ß-Glucan extracted from barley was found to possess significant antioxidant activity. The amount of antioxidant activity was influenced by different physiologic properties (e.g., structure and molecular size) of ß-glucan, which varied depending on the source and extraction method used. The antioxidant activity of ß-glucan was significantly higher than that of various polymers that are used as food additives. These results indicate that ß-glucan has promise as a polymeric excipient for supplement and food additive with antioxidant and other benefits, which may contribute to enhancing health and beauty.

6.
Circ J ; 76(4): 1004-11, 2012.
Article in English | MEDLINE | ID: mdl-22301847

ABSTRACT

BACKGROUND: We aimed to describe the recent clinical characteristics of Takayasu arteritis (TA). METHODS AND RESULTS: We enrolled 106 consecutive TA patients and compared the clinical characteristics of patients with TA onset before 1999 and after 2000, patients with onset at age less than 39 years and more than 40 years, patients with monophasic and relapsing-remitting clinical course, and patients with and without human lymphocyte antigen (HLA)-B52 allele. Among the patients with TA onset after 2000, the time from onset to diagnosis had decreased; the frequency of occlusion in aortic arch branches and the complication of moderate or severe aortic regurgitation (AR) had decreased, and the maximum dose of prednisolone and the use of immunosuppressive agents had increased. In patients with onset at age more than 40 years, the complications of coronary artery lesions and hypertension had increased, and the incidence of moderate or severe AR had decreased. In the relapsing-remitting group, the maximum dose of prednisolone and the use of immunosuppressive agents had increased, and the mean dose reduction rate of prednisolone was significantly high. There was no significant difference between patients with and without HLA-B52 allele. CONCLUSIONS: The prognosis of TA patients has improved over the past decade, which may be related to early diagnosis because of the development of noninvasive diagnostic imaging tools and improved medical treatments.


Subject(s)
Takayasu Arteritis , Adult , Age of Onset , Aged , Aortic Valve Insufficiency/etiology , Arterial Occlusive Diseases/etiology , Chi-Square Distribution , Disease Progression , Female , Glucocorticoids/administration & dosage , HLA-B52 Antigen/analysis , Humans , Immunosuppressive Agents/administration & dosage , Japan/epidemiology , Kaplan-Meier Estimate , Linear Models , Male , Middle Aged , Predictive Value of Tests , Prednisolone/administration & dosage , Recurrence , Retrospective Studies , Severity of Illness Index , Takayasu Arteritis/complications , Takayasu Arteritis/diagnosis , Takayasu Arteritis/immunology , Takayasu Arteritis/mortality , Takayasu Arteritis/therapy , Time Factors , Treatment Outcome , Vascular Surgical Procedures , Young Adult
7.
Circ J ; 75(8): 2005-12, 2011.
Article in English | MEDLINE | ID: mdl-21737957

ABSTRACT

BACKGROUND: The role of adiponectin (APN), an adipose tissue-specific secretory protein, on chronic rejection after cardiac transplantation in APN-sense transgenic mice (APN-SE) was evaluated. METHODS AND RESULTS: Heterotopic cardiac transplantation in major histocompatibility complex class II-mismatched mice was performed. B6.C-H-2(bm12)KhEg (Bm12) hearts were transplanted into APN-SE, and allografts were harvested at 8 weeks after transplantation. Quantitative polymerase chain reaction (PCR) and immunohistochemical staining showed that the expression of both AdipoR1 and AdipoR2 was induced in APN-SE recipients. Neointimal hyperplasia was significantly decreased in allografts transplanted into APN-SE (luminal occlusion, 8.9 ± 2.2%) compared to those transplanted into controls (49.4 ± 10.5%; P=0.011). APN-SE showed significantly reduced mRNA levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-2, IL-6, and monocyte chemoattractant protein-1 (MCP-1) by quantitative PCR. Western blot analysis revealed that the protein levels of IFN-γ and MCP-1 were reduced in APN-SE recipients. Proliferation of smooth muscle cells stimulated with activated T cells was suppressed by APN addition, and this effect was canceled by treatment with an adenosine monophosphate-activated protein kinase (AMPK) inhibitor. CONCLUSIONS: APN plays a critical role in the attenuation of chronic rejection by suppressing inflammatory cytokine and chemokine expression and enhancing APN receptor expression. APN plays a beneficial role in reducing the progression of cardiac allograft vasculopathy through the AMPK pathway.


Subject(s)
Adiponectin/metabolism , Coronary Vessels/metabolism , Graft Rejection/metabolism , Heart Transplantation , Neointima/metabolism , AMP-Activated Protein Kinases/antagonists & inhibitors , AMP-Activated Protein Kinases/genetics , AMP-Activated Protein Kinases/metabolism , Adiponectin/genetics , Adiponectin/pharmacology , Animals , Cell Proliferation/drug effects , Chronic Disease , Coronary Vessels/pathology , Graft Rejection/genetics , Graft Rejection/pathology , Hyperplasia , Inflammation/genetics , Inflammation/metabolism , Inflammation/pathology , Lymphocyte Activation/drug effects , Lymphocyte Activation/genetics , Mice , Mice, Transgenic , Myocytes, Smooth Muscle/metabolism , Neointima/genetics , Neointima/pathology , Protein Kinase Inhibitors/pharmacology , Receptors, Adiponectin/biosynthesis , Receptors, Adiponectin/genetics , T-Lymphocytes/metabolism , T-Lymphocytes/pathology , Transplantation, Homologous
8.
Circ J ; 75(8): 1982-91, 2011.
Article in English | MEDLINE | ID: mdl-21697605

ABSTRACT

BACKGROUND: Although some ß-blockers are effective for patients after acute myocardial infarction (AMI), few studies have compared their additive effects on renin-angiotensin system inhibitors (RAS-Is). METHODS AND RESULTS: The 251 consecutive AMI patients administered angiotensin-converting-enzyme inhibitors (ACE-Is) or angiotensin-II receptor blockers (ARBs) were retrospectively investigated and divided into 2 groups: treated without ß-blockers (no-ß-blocker group, n=80) or treated with ß-blockers before discharge (ß-blocker group, n=171; carvedilol [n=91] or bisoprolol [n=80]). The doses of RAS-Is used for patients in the no-ß-blocker group were at least double those used in the ß-blocker group. No significant differences between the 2 groups were observed with regard to baseline characteristics. After a 12-month follow-up, the survival and cardiac event-free rates in the ß-blocker group were significantly higher than those in the no-ß-blocker group. The percent change in blood pressure did not significantly differ between the 2 groups, but the levels of brain natriuretic peptide, metalloproteinase-2, and metalloproteinase-9 and the left ventricular ejection fraction improved significantly in the ß-blocker group compared with the no-ß-blocker group. Regarding the 2 ß-blockers, carvedilol treatment produced more favorable outcomes than bisoprolol. CONCLUSIONS: The data suggest that treatment with RAS-I in combination with ß-blocker is more effective for patients after AMI than treatment with RAS-I alone.


Subject(s)
Adrenergic beta-1 Receptor Antagonists/administration & dosage , Angioplasty, Balloon, Coronary , Angiotensin Receptor Antagonists/administration & dosage , Angiotensin-Converting Enzyme Inhibitors/administration & dosage , Bisoprolol/administration & dosage , Carbazoles/administration & dosage , Myocardial Infarction/therapy , Propanolamines/administration & dosage , Renin-Angiotensin System/drug effects , Aged , Aged, 80 and over , Blood Pressure/drug effects , Carvedilol , Drug Synergism , Female , Follow-Up Studies , Humans , Male , Middle Aged , Myocardial Infarction/physiopathology , Retrospective Studies , Time Factors
9.
Cardiovasc Res ; 89(2): 309-19, 2011 Feb 01.
Article in English | MEDLINE | ID: mdl-20978005

ABSTRACT

AIMS: Adiponectin (APN) has been reported to protect against ischaemia-reperfusion injury and hypertrophy. However, few reports have investigated the cardioprotective effects of APN in doxorubicin (DOX)-induced cardiomyopathy; therefore, we studied the cardioprotective mechanisms of APN in this model. METHODS AND RESULTS: In an in vivo study, we quantified the cardiac pathohistology of C57BL/6 mice [wild-type (WT) mice], APN transgenic mice with high APN concentrations [APN transgenic sense (SE) mice], and those with reduced APN concentrations [APN transgenic antisense (AS) mice] after intraperitoneal injections of DOX (4 mg/kg) weekly for 6 weeks. The survival rate after 14 days was significantly increased in APN-SE mice (WT vs. APN-AS vs. APN-SE: 40 vs. 17 vs. 73%, P < 0.05). We assessed myocardial pathohistological changes and observed that fibrosis and apoptosis were significantly decreased in APN-SE mice compared with those of the other groups. We also assessed DOX-induced apoptotic mechanisms in vitro using cultured cardiomyocytes isolated from neonatal WT mice. The expression of adenosine monophosphate-activated protein kinase (AMPK) and anti-apoptotic factor Bcl-2 increased, but that of pro-apoptotic factor Bax decreased in cardiomyocytes treated with highly concentrated APN. The protective effects of APN were reversed by the addition of an AMPK inhibitor (dorsomorphin) to the culture medium. CONCLUSION: These data suggest that APN improved cardiac function through anti-apoptotic effects by up-regulation of AMPK in DOX-induced cardiomyopathy in mice.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Antibiotics, Antineoplastic/toxicity , Apoptosis , Cardiomyopathies/prevention & control , Doxorubicin/toxicity , Myocardium/enzymology , AMP-Activated Protein Kinases/antagonists & inhibitors , Adiponectin/deficiency , Adiponectin/genetics , Adiponectin/metabolism , Animals , Apoptosis/drug effects , Cardiomyopathies/chemically induced , Cardiomyopathies/enzymology , Cardiomyopathies/genetics , Cardiomyopathies/pathology , Cells, Cultured , Fibrosis , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mitochondria, Heart/metabolism , Mitochondria, Heart/pathology , Myocardium/pathology , Myocytes, Cardiac/enzymology , Myocytes, Cardiac/pathology , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-bcl-2/metabolism , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Receptors, Adiponectin/metabolism , Time Factors , Up-Regulation , bcl-2-Associated X Protein/metabolism
10.
Circ J ; 74(6): 1127-34, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20354334

ABSTRACT

BACKGROUND: Although carvedilol and bisoprolol are effective medicines for the treatment of patients with heart failure (HF), only a few reports have compared their effects. This study was designed to compare the effects of them in patients with severe HF. METHODS AND RESULTS: A total of 655 consecutive patients with HF, categorized as New York Heart Association Class 3 or 4, were retrospectively investigated. Of these patients, 217 were administered beta-blockers after admission and were divided into 2 groups (carvedilol, n=110; bisoprolol, n=107). No significant differences were observed in their characteristics between the 2 groups prior to the introduction of the beta-blockers. After 18 months of follow-up, there were no significant differences in the survival and cardiac event-free rates between the 2 groups. In contrast, there were several significant differences in patients with atrial fibrillation (AF) (carvedilol, n=40; bisoprolol, n=43). The percent changes in heart rate and brain natriuretic peptide level improved significantly in the bisoprolol group than in the carvedilol group. Furthermore, more patients in the bisoprolol group were defibrillated from AF to sinus rhythm than those in the carvedilol group (48% vs 16%; P=0.03). CONCLUSIONS: Our data suggest that the 2 beta-blockers are equally effective in the improvement of severe HF, but bisoprolol shows favorable effects in patients with AF.


Subject(s)
Bisoprolol/therapeutic use , Carbazoles/therapeutic use , Heart Failure/drug therapy , Propanolamines/therapeutic use , Adrenergic beta-Antagonists/therapeutic use , Aged , Aged, 80 and over , Atrial Fibrillation/drug therapy , Carvedilol , Disease-Free Survival , Drug Evaluation , Female , Heart Failure/complications , Heart Failure/mortality , Heart Rate/drug effects , Humans , Male , Middle Aged , Natriuretic Peptide, Brain/blood , Retrospective Studies , Survival Rate , Treatment Outcome
11.
J Card Fail ; 15(4): 300-4, 2009 May.
Article in English | MEDLINE | ID: mdl-19398077

ABSTRACT

BACKGROUND: Few reports regarding the definition, epidemiology, and pathophysiology of acute decompensated heart failure (ADHF) are available. The clinical characteristics of 194 consecutive ADHF patients with abrupt onset of symptoms were investigated. METHODS AND RESULTS: Patients with acute coronary syndromes including acute myocardial infarction, acute pneumonia, severe valvular disease, and end-stage renal disease that required dialysis therapy were excluded. Patients were divided into 2 groups: rapid-progression group, onset within 24 hours before admission (n = 78); and gradual-progression group, onset more than 24 hours before admission (n = 52). No significant differences were observed in the age, gender, prescriptions, and hematological data between the 2 groups. The proportion of patients who drank excessive water was higher in the rapid-progression group. Systolic blood pressure, diastolic blood pressure, heart rate, left ventricular ejection fraction, and left ventricular wall thickness were greater in patients in the rapid-progression group. Indexes indicating left ventricular diastolic function were significantly deteriorated in the rapid-progression group. CONCLUSION: Excessive water intake, acute hypertension, and diastolic dysfunction are associated with the pathophysiology of abrupt-onset ADHF. Hypertensive patients with diastolic dysfunction should be treated cautiously to prevent the occurrence of ADHF.


Subject(s)
Heart Failure/diagnosis , Heart Failure/mortality , Acute Disease , Aged , Aged, 80 and over , Female , Hospital Mortality/trends , Hospitalization/trends , Humans , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/mortality , Male , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/mortality , Retrospective Studies , Time Factors , Ventricular Dysfunction, Left/diagnosis , Ventricular Dysfunction, Left/mortality
12.
Prog Neurol Surg ; 22: 45-62, 2009.
Article in English | MEDLINE | ID: mdl-18948719

ABSTRACT

The purpose of this study was to analyze tumor control and possible complications of gamma knife radiosurgery (GKRS) in patients with vestibular schwannomas using low marginal doses and conformal multiple shots to fit irregular tumor shapes. The authors evaluated 152 patients with more than 5 years of follow-up. Marginal doses were 9-15 Gy (median 12 Gy), with corresponding treatment volumes ranging from 0.1 to 18.7 cm3 (median 2.0 cm3). The number of isocenters varied from 2 to 24 shots (median 9 shots). The actuarial tumor control rates were 94% at 5 years and 92.4% at 8 years. Larger tumors (p < 0.0001) and those in younger patients (p = 0.018) tended to recur significantly more often. Useful hearing, facial and trigeminal functions were preserved at 71, 100 and 97.4%, respectively. Seventeen percent of all patients developed transient dizziness, with dizziness persisting in 2% of the total. Fifty-six other patients not included in the long-term evaluation consecutively underwent caloric testing and static stabilometry as well as neurological examinations to evaluate vestibular function in detail, both before and after GKRS. The results revealed 90% of the patients to have already developed vestibular dysfunction prior to the treatment despite reported symptoms of dizziness. GKRS did not significantly affect vestibular function. Hydrocephalus was recognized in 5.3% of all patients, and tended to occur in cases with larger tumors (p = 0.0024). GKRS provides a safe and effective therapy for small to medium-sized tumors. However, indications for larger tumors must be carefully considered, as they are more difficult to control and liable to produce ataxia due to transient expansion.


Subject(s)
Hearing , Neuroma, Acoustic/surgery , Radiosurgery , Adult , Aged , Aged, 80 and over , Facial Nerve/physiology , Female , Follow-Up Studies , Humans , Hydrocephalus/diagnosis , Magnetic Resonance Imaging , Male , Middle Aged , Neuroma, Acoustic/diagnostic imaging , Neuroma, Acoustic/pathology , Postoperative Complications/diagnosis , Radiation Dosage , Tomography, Emission-Computed, Single-Photon , Treatment Outcome , Trigeminal Nerve/physiology , Vestibular Nerve/physiology , Young Adult
13.
Eur J Immunol ; 36(6): 1527-36, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16708401

ABSTRACT

Alloiococcus otitidis has been found to be associated with otitis media with effusion. In this study we investigated whether TLR2 and collectins, surfactant protein A (SP-A) and mannose-binding lectin (MBL), interacted with A. otitidis. Both SP-A and MBL bound to A. otitidis in a Ca(2+)-dependent manner. A. otitidis induced IL-8 secretion from U937 cells and NF-kappaB activation in TLR2-transfected HEK293 cells. However, the cells transfected with the mutant TLR2(P681H) did not respond to A. otitidis. In addition, A. otitidis co-sedimented a recombinant soluble form of the extracellular TLR2 domain, indicating direct binding of the bacterium to TLR2. SP-A and MBL augmented the phagocytosis of A. otitidis by J774A.1 cells. The collectin-stimulated phagocytosis of A. otitidis was significantly attenuated when fucoidan and polyinosinic acid were co-incubated. Immunoblotting analysis revealed that MBL was present in the middle ear effusion from patients with otitis media. These results demonstrate that A. otitidis is a ligand for the collectins and TLR2, and that the collectins enhance the phagocytosis of A. otitidis by macrophages, suggesting important roles of the collectins and TLR2 in the innate immunity of the middle ear against A. otitidis infection.


Subject(s)
Gram-Positive Bacteria/metabolism , Gram-Positive Bacterial Infections/metabolism , Mannose-Binding Lectin/metabolism , Otitis Media with Effusion/metabolism , Otitis Media with Effusion/microbiology , Toll-Like Receptor 4/metabolism , Animals , Anti-Bacterial Agents/pharmacology , Gram-Positive Bacteria/immunology , Gram-Positive Bacterial Infections/immunology , Humans , Immunoblotting , Interleukin-8/immunology , Interleukin-8/metabolism , Ligands , Mannose-Binding Lectin/immunology , Mice , NF-kappa B/immunology , Otitis Media with Effusion/immunology , Phagocytosis/drug effects , Phagocytosis/immunology , Poly I/pharmacology , Polysaccharides/pharmacology , Rats , Signal Transduction/immunology , Toll-Like Receptor 2/immunology , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/immunology , U937 Cells
14.
Prostate ; 66(4): 386-91, 2006 Mar 01.
Article in English | MEDLINE | ID: mdl-16302262

ABSTRACT

BACKGROUND: The roles of Toll-like receptor 2 (TLR2) and Mycoplasma in prostate inflammation remain unclear. We investigated whether Mycoplasma induced inflammatory cytokine secretion through TLR2-mediated mechanism in prostate cancer cell line. METHODS: Cell surface expression of TLR2 on PC-3 cells were examined by flowcytometry. PC-3 cells were stimulated with Mycoplasma hominis (M. hominis), and IL-8 secretion and NF-kappaB activation were examined. RESULTS: PC-3 cells expressed TLR2 mRNA and cell surface TLR2 protein. The membrane fraction of M. hominis induced IL-8 secretion from PC-3 cells and NF-kappaB activation in a concentration-dependent manner. Transient transfection of the dominant negative mutant TLR2(P681H) into PC-3 cells attenuated M. hominis-induced IL-8 secretion and NF-kappaB activation. Antibody against the extracellular TLR2 domain significantly suppressed M. homnis-induced IL-8 secretion from the prostate cell lines including PC-3, PrEC, and transformed myofibroblasts. CONCLUSIONS: These results clearly demonstrate that the prostate cell line can secrete inflammatory cytokine in response to M. hominis through a TLR2-mediated mechanism.


Subject(s)
Interleukin-8/metabolism , Mycoplasma hominis/pathogenicity , Prostate/cytology , Prostate/pathology , Toll-Like Receptor 2/physiology , Flow Cytometry , Gene Expression Profiling , Humans , Inflammation , Male , NF-kappa B/physiology
15.
J Immunol ; 173(11): 6949-54, 2004 Dec 01.
Article in English | MEDLINE | ID: mdl-15557191

ABSTRACT

TLRs have been implicated in recognition of pathogen-associated molecular patterns. TLR4 is a signaling receptor for LPS, but requires MD-2 to respond efficiently to LPS. The purposes of this study were to examine the interactions of the extracellular TLR4 domain with MD-2 and LPS. We generated soluble forms of rTLR4 (sTLR4) and TLR2 (sTLR2) lacking the putative intracellular and transmembrane domains. sTLR4 consisted of Glu(24)-Lys(631). MD-2 bound to sTLR4, but not to sTLR2 or soluble CD14. BIAcore analysis demonstrated the direct binding of sTLR4 to MD-2 with a dissociation constant of K(D) = 6.29 x 10(-8) M. LPS-conjugated beads precipitated MD-2, but not sTLR4. However, LPS beads coprecipitated sTLR4 and MD-2 when both proteins were coincubated. The addition of sTLR4 to the medium containing the MD-2 protein significantly attenuated LPS-induced NF-kappaB activation and IL-8 secretion in wild-type TLR4-expressing cells. These results indicate that the extracellular TLR4 domain-MD-2 complex is capable of binding LPS, and that the extracellular TLR4 domain consisting of Glu(24)-Lys(631) enables MD-2 binding and LPS recognition to TLR4. In addition, the use of sTLR4 may lead to a new therapeutic strategy for dampening endotoxin-induced inflammation.


Subject(s)
Antigens, Surface/metabolism , Lipopolysaccharides/metabolism , Membrane Glycoproteins/antagonists & inhibitors , Membrane Glycoproteins/physiology , Receptors, Cell Surface/antagonists & inhibitors , Receptors, Cell Surface/physiology , Signal Transduction/immunology , Amino Acid Sequence , Antigens, Surface/genetics , Antigens, Surface/isolation & purification , Antigens, Surface/physiology , Cell Line , Extracellular Fluid/metabolism , Humans , Interleukin-8/antagonists & inhibitors , Interleukin-8/metabolism , Lipopolysaccharide Receptors/metabolism , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Lymphocyte Antigen 96 , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Molecular Sequence Data , NF-kappa B/antagonists & inhibitors , NF-kappa B/genetics , NF-kappa B/metabolism , Protein Binding/genetics , Protein Binding/immunology , Protein Structure, Tertiary/genetics , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Recombinant Proteins/metabolism , Signal Transduction/genetics , Solubility , Surface Plasmon Resonance , Toll-Like Receptor 2 , Toll-Like Receptor 4 , Toll-Like Receptors , Transcriptional Activation/immunology , Transfection
16.
J Immunol ; 171(1): 417-25, 2003 Jul 01.
Article in English | MEDLINE | ID: mdl-12817025

ABSTRACT

The lung collectin surfactant protein A (SP-A) has been implicated in the regulation of pulmonary host defense and inflammation. Zymosan induces proinflammatory cytokines in immune cells. Toll-like receptor (TLR)2 has been shown to be involved in zymosan-induced signaling. We first investigated the interaction of TLR2 with zymosan. Zymosan cosedimented the soluble form of rTLR2 possessing the putative extracellular domain (sTLR2). sTLR2 directly bound to zymosan with an apparent binding constant of 48 nM. We next examined whether SP-A modulated zymosan-induced cellular responses. SP-A significantly attenuated zymosan-induced TNF-alpha secretion in RAW264.7 cells and alveolar macrophages in a concentration-dependent manner. Although zymosan failed to cosediment SP-A, SP-A significantly reduced zymosan-elicited NF-kappaB activation in TLR2-transfected human embryonic kidney 293 cells. Because we have shown that SP-A binds to sTLR2, we also examined whether SP-A affected the binding of sTLR2 to zymosan. SP-A significantly attenuated the direct binding of sTLR2 to zymosan in a concentration-dependent fashion. From these results, we conclude that 1) TLR2 directly binds zymosan, 2) SP-A can alter zymosan-TLR2 interaction, and 3) SP-A down-regulates TLR2-mediated signaling and TNF-alpha secretion stimulated by zymosan. This study supports an important role of SP-A in controlling pulmonary inflammation caused by microbial pathogens.


Subject(s)
Down-Regulation/physiology , Lung/physiology , Membrane Glycoproteins/metabolism , NF-kappa B/metabolism , Pulmonary Surfactant-Associated Protein A/physiology , Receptors, Cell Surface/metabolism , Tumor Necrosis Factor-alpha/metabolism , Zymosan/metabolism , Zymosan/pharmacology , Animals , Cell Line , Extracellular Space/metabolism , Humans , Lung/drug effects , Lung/metabolism , Membrane Glycoproteins/antagonists & inhibitors , Membrane Glycoproteins/genetics , Mice , NF-kappa B/antagonists & inhibitors , Protein Binding/physiology , Protein Structure, Tertiary , Rats , Rats, Sprague-Dawley , Receptors, Cell Surface/antagonists & inhibitors , Receptors, Cell Surface/genetics , Signal Transduction/physiology , Toll-Like Receptor 2 , Toll-Like Receptors , Transfection , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Zymosan/antagonists & inhibitors
17.
J Biol Chem ; 277(27): 24315-20, 2002 Jul 05.
Article in English | MEDLINE | ID: mdl-11986301

ABSTRACT

Toll-like receptor 2 (TLR2) has been recognized to mediate cell signaling in response to peptidoglycan (PGN), a major cell wall component of Gram-positive bacteria. The mechanism by which TLR2 recognizes PGN is unknown. It is not even clear whether TLR2 directly binds to PGN. In this study, we generated a soluble form of recombinant TLR2 (sTLR2) possessing only its putative extracellular domain by using the baculovirus expression system to examine the direct interaction between sTLR2 and PGN. sTLR2 bound avidly to insoluble PGN (iPGN) from Staphylococcus aureus coated onto microtiter wells in a concentration-dependent manner. In contrast, sTLR2 exhibited a very weak binding to lipopolysaccharide. iPGN cosedimented sTLR2 after the mixture of iPGN and sTLR2 had been incubated and centrifuged. sTLR2 partially attenuated the iPGN-induced NF-kappaB activation in TLR2-transfected HEK 293 cells and the iPGN-induced IL-8 secretion in U937 cells. One of anti-human TLR2 monoclonal antibodies, which blocked iPGN-induced NF-kappaB activation in TLR2-transfected cells, inhibited the binding of sTLR2 to iPGN. In addition, we found that sCD14 interacted with sTLR2 and increased the binding of sTLR2 to iPGN. From these results, we conclude that the extracellular TLR2 domain directly binds to PGN.


Subject(s)
Drosophila Proteins , Membrane Glycoproteins/metabolism , Peptidoglycan/metabolism , Receptors, Cell Surface/metabolism , Staphylococcus aureus/physiology , Base Sequence , Binding Sites , DNA Primers , Humans , Immunoglobulin G , Kinetics , Lipopolysaccharide Receptors/chemistry , Lipopolysaccharide Receptors/metabolism , Membrane Glycoproteins/chemistry , Membrane Glycoproteins/immunology , Polymerase Chain Reaction , Receptors, Cell Surface/chemistry , Receptors, Cell Surface/immunology , Recombinant Proteins/metabolism , Toll-Like Receptor 2 , Toll-Like Receptors , U937 Cells
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