Protease-activated receptors (PARs) are involved in the contribution of airway epithelial cells to the development of inflammation by release of pro- and anti-inflammatory mediators. Here, we evaluated in epithelial cells the influence of LPS and continuous PAR activation on PAR expression level and the release of the proinflammatory chemokine IL-8. We studied primary human small airway epithel...

Serine proteinases like thrombin can signal to cells by the cleavage/activation of proteinase-activated receptors (PARs). Although thrombin is a recognized physiological activator of PAR(1) and PAR(4), the endogenous enzymes responsible for activating PAR(2) in settings other than the gastrointestinal system, where trypsin can activate PAR(2), are unknown. We tested the hypothesis that the huma...

Thrombin is a multifunctional enzyme which has key roles in coagulation cascade and inflammatory events. The pro-inflammatory functions of thrombin occur by different mechanisms including increasing mast cell degranulation, up-regulating the expression of cell adhesion molecules (CAMs) and promoting the secretion of inflammatory chemokines and cytokines. Dysregulated signaling functions of thro...

The par-3 gene is required for establishing polarity in early C. elegans embryos. Embryos from par-3 homozygous mothers show defects in segregation of cytoplasmic determinants and in positioning of the early cleavage spindles. We report here that the PAR-3 protein is asymmetrically distributed at the periphery of the zygote and asymmetrically dividing blastomeres of the germline lineage. The PA...

The par genes are required to establish polarity in the Caenorhabditis elegans embryo. Mutations in two of these genes, par-3 and par-6, exhibit similar phenotypes. A third gene, pkc-3, gives a similar phenotype when the protein is depleted by RNA interference. PAR-3 and PKC-3 protein are colocalized to the anterior periphery of asymmetrically dividing cells of the germline lineage and the peri...

Thrombin promotes vascular smooth muscle cell (SMC) proliferation and inflammation via protease-activated receptor (PAR)-1. A further thrombin receptor, PAR-3, acts as a PAR-1 cofactor in some cell-types. Unlike PAR-1, PAR-3 is dynamically regulated at the mRNA level in thrombin-stimulated SMC. This study investigated the mechanisms controlling PAR-3 expression. In human vascular SMC, PAR-3 siR...

A new simple and rapid dispersive liquid-liquid microextraction has been applied to preconcentrate tracelevels of zinc as a prior step to its determination by spectrophotometric method. In the proposed method, 4-(2-pyridylazo) resorcinol (PAR) is used as a chelating agent, and chloroform and ethanol are selected asextraction and dispersive solvent. The optimization strategy is carried out by us...

A hallmark of polarized cells is the segregation of the PAR polarity regulators into asymmetric domains at the cell cortex1,2. Antagonistic interactions involving two conserved kinases, atypical protein kinase C (aPKC) and PAR-1, have been implicated in polarity maintenance1,2, but the mechanisms that initiate the formation of asymmetric PAR domains are not understood. Here, we describe one pat...