MPO Levels (mpo + level)

Distribution by Scientific Domains


Selected Abstracts


Myeloperoxidase and chlorinated peptides in osteoarthritis: potential biomarkers of the disease

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 9 2007
Marla J. Steinbeck
Abstract Osteoarthritis (OA) is a disabling condition in which multiple initiating events or conditions (heritable and nonheritable) result in eventual loss of articular cartilage. However, the etiology of OA remains poorly understood, and diagnosis of early disease is difficult due to the lack of specific identifiers. Recent literature suggests that a series of inflammatory processes may be involved in initiating and propagating OA. We hypothesized that products of neutrophils and macrophages, namely myeloperoxidase (MPO), a specific enzyme responsible for the production of both highly reactive hypochlorous acid (HOCl) and chlorine gas (Cl2) and chlorinated peptides, may be present in the synovial fluid of patients with OA. We examined the synovial fluid from 30 patients to identify and profile the presence of MPO. We divided the samples into three groups using radiographic and clinical assessment: (1) control, patients with acute knee injury with no history of OA and no radiographic evidence of OA; (2) early OA, patients with a mild OA based on radiographs; and (3) late OA, patients with a longstanding history of OA and with radiographic evidence of complete joint loss. Patients with early OA demonstrated significantly elevated levels of MPO. We also demonstrated the presence of HOCl and Cl2 modified proteins (Cl-peptides) in early OA synovial fluid samples by liquid chromatography and mass spectrometry. Patients in the control and advanced OA groups demonstrated little elevation in MPO levels and Cl-peptides were undetectable. These results indicate that MPO and Cl-peptides may serve as diagnostic markers for the detection of early OA. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1128,1135, 2007 [source]


Melatonin, a potent regulator of hemeoxygenase-1, reduces cardiopulmonary bypass-induced renal damage in rats

JOURNAL OF PINEAL RESEARCH, Issue 3 2009
Zhongqiu Wang
Abstract:, Acute renal dysfunction is a frequent complication after cardiac surgery with cardiopulmonary bypass (CPB). This study was designed to evaluate the potential protective effect of melatonin on CPB-induced renal damage in a rat model. Forty male Sprague,Dawley rats were randomly divided into four groups: sham, control (CPB + placebo), low dose of melatonin (CPB + 10 mg/kg melatonin) and high dose of melatonin (CPB + 20 mg/kg melatonin). Blood samples were collected at the beginning, at the end of CPB, and at 0.5, 1, 2, 3, and 24 hr postoperation. Serum creatinine and blood urea nitrogen levels were assayed. Rats were killed 24 hr after surgery, the histologic appearance of the kidney and malondialdehyde (MDA), myeloperoxidase (MPO), catalase (CAT) and superoxide dismutase (SOD) contents were determined. The expression levels of hemeoxygenase-1 (HO-1) protein and gene were determined using western blotting and real-time PCR, respectively. In the control group, CPB surgery significantly increased urea, creatinine levels in serum, MDA and MPO levels in tissues, while decreasing SOD and CAT activities in tissues. Histopathologic findings of the control group confirmed that there was renal impairment by cast formation and tubular necrosis in the tubular epithelium. These changes were markedly reversed in both low dose of melatonin and high dose of melatonin groups. Furthermore, HO-1 gene transcript and protein were significantly upregulated in the kidney tissues after melatonin treatment compared with the placebo treatment. Our findings show that melatonin was effective in preventing CPB-induced renal damage probably through its antioxidant function and upregulation of HO-1. [source]


Melatonin treatment protects against ischemia/reperfusion-induced functional and biochemical changes in rat urinary bladder

JOURNAL OF PINEAL RESEARCH, Issue 3 2003
Göksel, ener
Abstract: Reactive oxygen metabolites play important roles in ischemia/reperfusion (I/R) injury in several systems. The aim of this study was to investigate the role of melatonin against I/R injury of the rat urinary bladder. The abdominal aorta was clamped to induce ischemia for 30 min, then the animals were subjected to 60 min of reperfusion. Melatonin (10 mg/kg, i.p.) or the vehicle (control 1% alcohol i.p.) was administered before I/R. After decapitation, the bladder was removed and the tissue was either used for functional studies or stored for measurement of products of lipid peroxidation (LP), glutathione (GSH) levels and myeloperoxidase activity (MPO). Bladder strips were suspended in oxygenated Tyrode's buffer at 37°C and isometric contractions to carbachol (CCh; 10,8,10,4 m) were recorded. In the I/R group, the contractile responses of the bladder strips were lower than those of the control group (P < 0.01,0.001) and were reversed by treatment with melatonin (P < 0.05,0.001). LP which was higher in I/R group compared with control (27.68 ± 1.69 and 10.59 ± 1.27 nmol/g, respectively; P < 0.001) was partially reversed by melatonin (19.01 ± 1.85 nmol/g; P < 0.01). Similarly, GSH showed a decrease in the I/R group compared with controls (0.27 ± 0.03 and 0.43 ± 0.04 ,mol/g, respectively; P < 0.05) and melatonin prevented this effect completely (0.45 ± 0.04 , mol/g; P < 0.05). MPO activity in the I/R group (4.19 ± 0.08 U/g) was significantly higher than that of the control group (1.41 ± 0.08 U/g; P < 0.001) and melatonin treatment reduced MPO levels compared with I/R alone (3.16 ± 0.07; P < 0.001). Melatonin almost completely reversed the low contractile responses of rat urinary bladder strips to CCh and prevented oxidative tissue damage following I/R. [source]


Effect of low-dose theophylline on airway inflammation in COPD

RESPIROLOGY, Issue 2 2004
Motoko KOBAYASHI
Objective: Recent studies have shown that theophylline may exert anti-inflammatory effects on neutrophils. We undertook to assess the effect of theophylline on airway inflammation in COPD. Methodology: We performed a 4-week randomized double-blind, placebo-controlled study in 11 theophylline-naive patients with mild to moderate COPD. After a 1-week run-in period, six subjects were administered 400 mg/day theophylline (Theodur; Nikken Chemicals Co. Ltd, Tokyo, Japan) for 4 weeks, while five subjects were administered a placebo. Induced sputum was obtained before and after the run-in period and then after 2 and 4 weeks of treatment. Cell differential count and levels of interleukin-8, matrix metalloproteinase-9, neutrophil elastase (NE), myeloperoxidase (MPO), ,1 -antitrypsin (,1 -AT), leukotriene B4 and tissue inhibitor of metalloproteinases-1 (TIMP-1) were assessed. Results: No variable was significantly different during the run-in period or with placebo treatment. In contrast, theophylline treatment significantly decreased NE and MPO levels at 4 weeks, although the cell differential count did not change appreciably as a result of treatment. Conclusion: These results suggest that 4 weeks of theophylline treatment attenuates neutrophil-associated inflammation in the airways of mild to moderate COPD patients. However, the clinical benefits remain to be determined. [source]


Effect of renal and non-renal ischemia/reperfusion on cell-mediated immunity in organs and plasma

APMIS, Issue 2 2010
ANNE C. BRØCHNER
Brøchner AC, Dagnæs-Hansen F, Toft P. Effect of renal and non-renal ischemia/reperfusion on cell-mediated immunity in organs and plasma. APMIS 2010; 118: 101,7. Acute renal failure (ARF) is a common morbidity factor among patients in the intensive care unit, reaching an incidence from 3% to 30% depending on the definition of ARF and the population. Although the majority of the patients with ARF are treated with continuous renal replacement therapy, the mortality rate still remains above 50%. The causes of death are primarily extra-renal and include infection, shock, septicemia, and respiratory failure. We wanted to evaluate the cell-mediated inflammatory response of renal ischemia,reperfusion (I/R) and non-renal I/R, in blood and in distant organs. In our study, 80 mice were divided into four groups. The following surgeries were performed on the groups compared: bilateral renal I/R by clamping, unilateral renal ischemia, anesthesia only, and unilateral hind leg I/R. Half of the animals were killed after 2 h and the other half after 24 h. To assess the inflammatory response, we measured myeloperoxidase (MPO) in the organs, and CD 11b and major histocompatibility complex (MHC) II-positive cells in the blood. Non-renal I/R elicited the most elevated levels of MPO in extra-renal tissue such as the lungs. There was a trend toward higher MPO levels in the kidney following renal I/R. All kinds of I/R induced an upregulation of the adhesion molecule CD 11b and a downregulation of MHC II. Renal and non-renal I/R induced neutrophil infiltration in distant organs. Renal I/R does not induce a larger cell-mediated inflammatory response in blood and organs than non-renal I/R. [source]


Reduced post-operative neutrophil activation in liver transplant recipients suffering from post-hepatitic cirrhosis

CLINICAL TRANSPLANTATION, Issue 6 2009
Björn Jüttner
Abstract:, Background:, It has been supposed that liver transplant recipients with hepatitis C virus infection have a higher incidence of infectious complications after transplantation. This study was designed to investigate whether neutrophil function is immediately affected by liver transplantation. Methods:, Biochemical values, plasma levels of myeloperoxidase (MPO), hydrogen peroxide production of neutrophils and neutrophil,platelet complexes were analyzed in 32 patients who underwent liver transplantation and 20 healthy volunteers. Results:, MPO levels were significantly increased 24 h after reperfusion. In post-hepatitic patients levels were significantly lower three d up to one wk post-transplant than in patients due to other liver diseases. One wk post-operatively the respiratory burst activity following N -formyl-methionyl-leucylphenylalanine (fMLP) or (tumor necrosis factor-,) TNF-,/fMLP stimulation was depressed in post-hepatitic recipients. Respiratory burst stimulated with phorbol 12-myristate 13-acetate in these patients was increased one wk after transplantation. One d after transplantation the neutrophil,platelet complexes decreased significantly throughout the post-operative period. Conclusions:, The results of this study suggest a reduced post-operative neutrophil activation in liver transplant recipients suffering from post-hepatitic cirrhosis compared to cirrhosis due to other causes. We hypothesized that neutrophil dysfunction in those patients depends on the underlying disease with an increased susceptibility to bacterial or fungal infections. [source]