Parkinson's disease (PD) is characterized by a loss of ventral midbrain dopaminergic neurons, which can be modeled by the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Inflammatory oxidants have emerged as key contributors to PD- and MPTP-related neurodegeneration. Here, we show that myeloperoxidase (MPO), a key oxidant-producing enzyme during inflammation, is upregulated in t...

Background. Renal-limited myeloperoxidase vasculitis with simultaneous rheumatoid arthritis is reported as a rare occurrence. Review of literature suggests that most patients had a diagnosis of rheumatoid arthritis for several years prior to presenting with renal failure from myeloperoxidase vasculitis. Case Presentation. A 58-year-old Caucasian male presented to the hospital experiencing malai...

colitis is an inflammatory disease of the intestine with unknown etiology involving multiple immune, genetic and environmental factors. we were interested to examine the effect of total extract from pycnocycla spinosa boiss. on the treatment of experimental colitis. mediators involved in colonic inflammation are prostaglandins, interleukins, leukotriene as well as an increase in myeloperoxidase...

An 86-year-old woman was admitted with hemoptysis and rapid deterioration of renal function. Renal biopsy disclosed necrotizing crescentic glomerulonephritis. Based on positivity for serum myeloperoxidase antineutrophil cytoplasmic autoantibody (MPO-ANCA), MPO-ANCA-associated glomerulonephritis was diagnosed. Steroid pulse therapy was performed, but the patient died after the second course. Aut...

Goodpasture disease (GD) is a rare autoimmune disorder characterized by the development of pathologic autoantibodies against both glomerular and alveolar basal membranes. Approximately one third of the patients with GD are also positive for anti-neutrophil cytoplasmic antibody (ANCA). In this case report, a 74-year-old woman was diagnosed as having myeloperoxidase (MPO)-ANCA-positive GD with se...

Introduction We report a severe case of chronic non-bacterial osteomyelitis (CNO) associated with total myeloperoxidase (MPO) deficiency. Chronic non-bacterial osteomyelitis (CNO) is often considered an autoinflammatory disease. In pediatric literature CNO is often referred to as chronic recurrent multifocal ostemyelitis (CRMO). CNO is occasionally associated with extremely rare monogenic disea...

A cytotoxic effect of human neutrophils on mammalian tumor cells is demonstrated. Cytotoxicity depends on the presence of intact neutrophils, phagocytosable particles, and a halide cofactor and is inhibited by azide, cyanide, and catalase. Neutrophils from patients with myeloperoxidase (MPO) deficiency or defective H1O2 production are not cytotoxic, but activity is resotred by addition of purif...

In response to antineutrophil cytoplasmic antibody (ANCA), activated neutrophils release decondensed chromatin associated with cytoplasmic granular proteins composed of proteolytic enzymes and myeloperoxidase (MPO); these complexes are named neutrophil extracellular traps (NETs). NET formation requires peptidylarginine deiminase 4 (PAD4) to citrullinate chromatin histones and also MPO and neutr...

A 55-year-old woman presented with deafness, increased levels of myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA), and renal insufficiency with proteinuria and hematuria. Renal biopsy revealed crescentic glomerulonephritis with the linear deposition of immunoglobulin G along the glomerular basement membrane (GBM) and peritubular capillaritis. The anti-GBM antibody levels on admi...

Myeloperoxidase (MPO) is an important enzyme that catalyzes the reaction between hydrogen peroxide and chloride to generate hypochlorous acid, which oxidizes a range of biomolecules and has been associated with inflammatory diseases. The synthetic compounds N-phenylmaleimide (NFM) and 4-methyl-N-phenylmaleimide (Me-NFM) increased the MPO activity in vitro (of isolated enzyme and in isolated cel...