title: Serum paraoxonase type-1 activity in pigs: assay validation and evolution after an induced experimental inflammation.
abstract: Paraoxonase 1 (PON1) is a serum enzyme synthesised and secreted primarily by the liver. It possesses anti-inflammatory properties limiting the production of pro-inflammatory mediators. The objectives of this study were to validate three spectrophotometric assays for the quantification of PON1 activity in pig serum, and to determine if PON1 activity in porcine behaves as a negative acute phase protein (APP), decreasing in inflammatory conditions. An analytical validation using three different substrates - 5-thiobutil butyrolactone (TBBL), phenylacetate (PA) and 4-(p)-nitrophenyl acetate (pNA) - was performed. In addition, inflammation was experimentally induced in five pigs by subcutaneous injection of turpentine oil, while five control pigs were left untreated. The treated pigs showed significant increases in CRP and decreases in albumin, indicating an inflammatory condition. The three substrates used would be suitable for PON1 activity measurements in serum samples, since they offer adequate precision (coefficients of variation<10%), sensitivity (0.01, 0.15, 0.02 U/mL for TBBL, pNA and PA respectively) and accuracy (r=0.99). In addition, PON1 behaves as a negative APP in pigs since a significant decrease (P<0.05) in its activity after 72 h of the induction of the inflammation was observed with all substrates.
authors.affiliation: Interdisciplinary Laboratory of Clinical Analysis, Interlab-UMU, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Espinardo, Murcia, Spain.
authors.forename: Damián
authors.initials: D
authors.lastname: Escribano
authors.affiliation: Interdisciplinary Laboratory of Clinical Analysis, Interlab-UMU, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Espinardo, Murcia, Spain.
authors.forename: Asta
authors.initials: A
authors.lastname: Tvarijonaviciute
authors.affiliation: Interdisciplinary Laboratory of Clinical Analysis, Interlab-UMU, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Espinardo, Murcia, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Tecles
authors.affiliation: Interdisciplinary Laboratory of Clinical Analysis, Interlab-UMU, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Espinardo, Murcia, Spain. Electronic address: jjceron@um.es.
authors.forename: José J
authors.initials: JJ
authors.lastname: Cerón
mesh_terms: D000818:Animals; D043303:Aryldialkylphosphatase / Q000097:blood* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D007249:Inflammation / Q000097:blood / Q000139:chemically induced* / Q000378:metabolism; D015203:Reproducibility of Results; D013057:Spectrum Analysis / Q000379:methods; D013552:Swine; D013553:Swine Diseases / Q000139:chemically induced* / Q000378:metabolism; D014425:Turpentine / Q000633:toxicity
chemical_list: D043303:Aryldialkylphosphatase; D014425:Turpentine
keywords: Acute phase protein; Assay validation; Inflammation; Paraoxonase type-1; Serum pigs