-
International Journal of Molecular... Jul 2023Salivary myeloperoxidase (MPO) is a key mediator of the oral immune system, acting as an enzyme that utilises HO to generate molecules with high bactericidal activity.... (Review)
Review
Salivary myeloperoxidase (MPO) is a key mediator of the oral immune system, acting as an enzyme that utilises HO to generate molecules with high bactericidal activity. While MPO determination in plasma is quite common, the use of saliva is still rare. Our systematic review was designed to answer the question "Are salivary levels of myeloperoxidase altered in patients with systemic diseases?". Following the inclusion and exclusion criteria, we included twenty-six studies. Altered MPO levels in saliva were most commonly found in patients with cardiovascular and gastrointestinal diseases. Most studies concerned unstimulated whole saliva, and only a few of them stimulated, mainly by chewing paraffin. Enzyme-linked immunosorbent assay (ELISA) was the most common method for determination of MPO concentrations in saliva. Increased salivary MPO levels were more often observed for inflammatory diseases, except patients with inflammatory bowel diseases who were eligible for biologic therapy. In conclusion, MPO could be altered in the saliva of patients with systematic diseases, especially cardiovascular or gastrointestinal diseases. However, further investigations are recommended to validate these outcomes.
Topics: Humans; Enzyme-Linked Immunosorbent Assay; Hydrogen Peroxide; Peroxidase; Saliva
PubMed: 37569455
DOI: 10.3390/ijms241512078 -
International Journal of Molecular... Apr 2020Multiple system atrophy (MSA) is a rare, severe, and rapidly progressive neurodegenerative disorder categorized as an atypical parkinsonian syndrome. With a mean life... (Review)
Review
Multiple system atrophy (MSA) is a rare, severe, and rapidly progressive neurodegenerative disorder categorized as an atypical parkinsonian syndrome. With a mean life expectancy of 6-9 years after diagnosis, MSA is clinically characterized by parkinsonism, cerebellar ataxia, autonomic failure, and poor l-Dopa responsiveness. Aside from limited symptomatic treatment, there is currently no disease-modifying therapy available. Consequently, distinct pharmacological targets have been explored and investigated in clinical studies based on MSA-related symptoms and pathomechanisms. Parkinsonism, cerebellar ataxia, and autonomic failure are the most important symptoms targeted by symptomatic treatments in current clinical trials. The most prominent pathological hallmark is oligodendroglial cytoplasmic inclusions containing alpha-synuclein, thus classifying MSA as synucleinopathy. Additionally, myelin and neuronal loss accompanied by micro- and astrogliosis are further distinctive features of MSA-related neuropathology present in numerous brain regions. Besides summarizing current symptomatic treatment strategies in MSA, this review critically reflects upon potential cellular targets and disease-modifying approaches for MSA such as (I) targeting α-syn pathology, (II) intervening neuroinflammation, and (III) neuronal loss. Although these single compound trials are aiming to interfere with distinct pathogenetic steps in MSA, a combined approach may be necessary to slow down the rapid progression of the oligodendroglial associated synucleinopathy.
Topics: Adrenergic alpha-1 Receptor Agonists; Animals; Disease Models, Animal; Humans; Induced Pluripotent Stem Cells; Monoamine Oxidase Inhibitors; Multiple System Atrophy; Neuroglia; Peroxidase; alpha-Synuclein
PubMed: 32316335
DOI: 10.3390/ijms21082775 -
International Journal of Molecular... Sep 2020Thiocyanate (SCN) is a pseudohalide anion omnipresent across mammals and is particularly concentrated in secretions within the oral cavity, digestive tract and airway.... (Review)
Review
Thiocyanate (SCN) is a pseudohalide anion omnipresent across mammals and is particularly concentrated in secretions within the oral cavity, digestive tract and airway. Thiocyanate can outcompete chlorine anions and other halides (F, Br, I) as substrates for myeloperoxidase by undergoing two-electron oxidation with hydrogen peroxide. This forms their respective hypohalous acids (HOX where X = halides) and in the case of thiocyanate, hypothiocyanous acid (HOSCN), which is also a bactericidal oxidative species involved in the regulation of commensal and pathogenic microflora. Disease may dysregulate redox processes and cause imbalances in the oxidative profile, where typically favoured oxidative species, such as hypochlorous acid (HOCl), result in an overabundance of chlorinated protein residues. As such, the pharmacological capacity of thiocyanate has been recently investigated for its ability to modulate myeloperoxidase activity for HOSCN, a less potent species relative to HOCl, although outcomes vary significantly across different disease models. To date, most studies have focused on therapeutic effects in respiratory and cardiovascular animal models. However, we note other conditions such as rheumatic arthritis where SCN administration may worsen patient outcomes. Here, we discuss the pathophysiological role of SCN in diseases where MPO is implicated.
Topics: Animals; Humans; Peroxidase; Rheumatic Fever; Thiocyanates
PubMed: 32899436
DOI: 10.3390/ijms21176450 -
Rheumatology (Oxford, England) Nov 2023
Topics: Humans; Antibodies, Antineutrophil Cytoplasmic; Granulomatosis with Polyangiitis; Peroxidase
PubMed: 37137279
DOI: 10.1093/rheumatology/kead173 -
Scientific Reports May 2023This work was conducted to study positive and negative impacts of cerium (Ce) and samarium (Sm) on two cultivars (Arta and Baharan) in wheat plant. Symbols of stress...
This work was conducted to study positive and negative impacts of cerium (Ce) and samarium (Sm) on two cultivars (Arta and Baharan) in wheat plant. Symbols of stress such as proline, malondialdehyde (MDA) and antioxidant enzymes, which may be complicated in the suppression responses of plants, were also studied. Wheat plants were exposed to 0, 2500, 5000, 7500, 10,000 and 15,000 μM of Ce and Sm for 7 days. The growth enhanced in plants treated with lesser Ce and Sm concentration (2500 μM) and declined in plants treated with upper concentrations as compared to untreated plants. The treatment with 2500 μM of Ce and Sm increased dry weigh in Arta by 68.42 and 20% and in Baharan by 32.14% and 27.3%. Thus, Ce and Sm had hormesis effect on growth in wheat plants. According to plant's growth parameter patterns, Arta cultivar had more sensitive to Sm than to Ce, whereas Baharan cultivar had sensitive to Ce than to Sm. Our results indicated impact of Ce and Sm on proline accumulation depended on the dosage of Ce and Sm. It was observed that Ce and Sm accumulated in wheat plants at higher exposure doses. Increment of MDA content by Ce and Sm treatments showed that these metals caused oxidative stress in wheat plants. Ce and Sm blocked enzymatic antioxidant system (superoxide dismutases, peroxidase and polyphenol peroxidase) in wheat. In wheat plants treated with lower Ce and Sm concentrations higher amounts of non-enzymatic antioxidant metabolites were detected. Thus, we showed the potential negative impact of unsuitable utilization of REEs in plants and suggested growth and interruption in physiological and biochemical mechanisms as a possible factor to recognize the underlying toxicological processes.
Topics: Antioxidants; Triticum; Samarium; Cerium; Peroxidase; Plants; Proline
PubMed: 37217773
DOI: 10.1038/s41598-023-35561-2 -
International Journal of Molecular... Jul 2023Oxidases and peroxidases have found application in the field of chlorine-free organic dye degradation in the paper, toothpaste, and detergent industries. Nevertheless,...
Oxidases and peroxidases have found application in the field of chlorine-free organic dye degradation in the paper, toothpaste, and detergent industries. Nevertheless, their widespread use is somehow hindered because of their cost, availability, and batch-to-batch reproducibility. Here, we report the catalytic proficiency of a miniaturized synthetic peroxidase, Fe-Mimochrome VI*a, in the decolorization of four organic dyes, as representatives of either the heterocyclic or triarylmethane class of dyes. Fe-Mimochrome VI*a performed over 130 turnovers in less than five minutes in an aqueous buffer at a neutral pH under mild conditions.
Topics: Peroxidase; Coloring Agents; Reproducibility of Results; Peroxidases; Catalysis
PubMed: 37446248
DOI: 10.3390/ijms241311070 -
Journal of the American Society of... May 2022
Topics: Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis; Antibodies, Antineutrophil Cytoplasmic; Cathepsin C; Humans; Myeloblastin; Peroxidase
PubMed: 35396261
DOI: 10.1681/ASN.2022030309 -
Chemical & Pharmaceutical Bulletin 2022Protein bioconjugation has become an increasingly important research method for introducing artificial functions in to protein with various applications, including... (Review)
Review
Protein bioconjugation has become an increasingly important research method for introducing artificial functions in to protein with various applications, including therapeutics and biomaterials. Due to its amphiphilic nature, only a few tyrosine residues are exposed on the protein surface. Therefore, tyrosine residue has attracted attention as suitable targets for site-specific modification, and it is the most studied amino acid residue for modification reactions other than lysine and cysteine residues. In this review, we present the progress of our tyrosine chemical modification studies over the past decade. We have developed several different catalytic approaches to selectively modify tyrosine residues using peroxidase, laccase, hemin, and ruthenium photocatalysts. In addition to modifying tyrosine residues by generating radical species through single-electron transfer, we have developed a histidine modification method that utilizes singlet oxygen generated by photosensitizers. These highly reactive chemical species selectively modify proteins in close proximity to the enzyme/catalyst. Taking advantage of the spatially controllable reaction fields, we have developed novel methods for site-specific antibody modification, detecting hotspots of oxidative stress, and target identification of bioactive molecules.
Topics: Biocatalysis; Coordination Complexes; Hemin; Humans; Laccase; Molecular Structure; Peroxidase; Protein Processing, Post-Translational; Tyrosine
PubMed: 35110442
DOI: 10.1248/cpb.c21-00915 -
Proceedings of the National Academy of... Jul 2020Bromine and peroxidasin (an extracellular peroxidase) are essential for generating sulfilimine cross-links between a methionine and a hydroxylysine within collagen IV, a...
Bromine and peroxidasin (an extracellular peroxidase) are essential for generating sulfilimine cross-links between a methionine and a hydroxylysine within collagen IV, a basement membrane protein. The sulfilimine cross-links increase the structural integrity of basement membranes. The formation of sulfilimine cross-links depends on the ability of peroxidasin to use bromide and hydrogen peroxide substrates to produce hypobromous acid (HOBr). Once a sulfilimine cross-link is created, bromide is released into the extracellular space and becomes available for reutilization. Whether the HOBr generated by peroxidasin is used very selectively for creating sulfilimine cross-links or whether it also causes oxidative damage to bystander molecules (e.g., generating bromotyrosine residues in basement membrane proteins) is unclear. To examine this issue, we used nanoscale secondary ion mass spectrometry (NanoSIMS) imaging to define the distribution of bromine in mammalian tissues. We observed striking enrichment of bromine (Br, Br) in basement membranes of normal human and mouse kidneys. In peroxidasin knockout mice, bromine enrichment of basement membranes of kidneys was reduced by ∼85%. Proteomic studies revealed bromination of tyrosine-1485 in the NC1 domain of α2 collagen IV from kidneys of wild-type mice; the same tyrosine was brominated in collagen IV from human kidney. Bromination of tyrosine-1485 was reduced by >90% in kidneys of peroxidasin knockout mice. Thus, in addition to promoting sulfilimine cross-links in collagen IV, peroxidasin can also brominate a bystander tyrosine. Also, the fact that bromine enrichment is largely confined to basement membranes implies that peroxidasin activity is largely restricted to basement membranes in mammalian tissues.
Topics: Animals; Basement Membrane; Biopsy; Bromates; Bromides; Bromine; Cells, Cultured; Collagen Type IV; Extracellular Matrix Proteins; Humans; Hydrogen Peroxide; Imines; Kidney; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Proteomics; Peroxidasin
PubMed: 32571911
DOI: 10.1073/pnas.2007749117 -
The Journal of Histochemistry and... 2022Immunocytochemical (ICC) techniques are frequently used in basic and clinical research. Here, we focus on the importance of using antisera/antibodies at optimal...
Immunocytochemical (ICC) techniques are frequently used in basic and clinical research. Here, we focus on the importance of using antisera/antibodies at optimal dilutions to achieve specificity and reduce costs. Unfortunately, the basic principle, the necessity to test method specificity of the staining by a series of increasing dilutions of primary antiserum/antibodies, is only occasionally seen in papers using ICC. Many researchers rely on the company's information or others' published data. In this study, we show examples with monoclonal antibodies used in the peroxidase-based ICC technique in mouse and guinea pig brain sections. We show images of ICC staining of phospho-S129 alpha-synuclein in A53T mice and NeuN in guinea pig brains and demonstrate that optimal staining with them can be achieved at least at two to three orders of magnitude higher dilutions than generally used in the literature. We strongly recommend that when antisera/antibodies are used for the first time in any laboratory, independent of what the manufacturer or vendor recommends or are found in the literature, a dilution curve should be set up to identify the optimal dilution. This practice provides not only the highest specificity but is also an economic approach.
Topics: Mice; Animals; Guinea Pigs; Immunohistochemistry; Immune Sera; Antibodies, Monoclonal; Peroxidase; Brain
PubMed: 36514198
DOI: 10.1369/00221554221146213