L-Arginine Transport and Nitric Oxide Production in Kinin Receptor B1-/- Endothelial Cells.

Kinins are important vasoactive peptides, but the role of the B1 receptor subtype in the vascular control is poorly understood. This study analyzed the nitric oxide (NO) release, L-arginine (L-Arg) uptake and the expression of the cationic amino acid transporter (CAT) -1 in endothelial cells obtained from B1 receptor knockout (B1-/-) and wild type (WT) mice. NO production was assessed through a fluorescent dye in living cells stimulated with acetylcholine. L-Arg uptake was determined indirectly in the culture medium by HPLC, in the presence or absence of the CAT-1 blocker N-ethylmaleimide (NEM). CAT-1 mRNA levels and protein expression were determined by qPCR and western blot, respectively. NO release was significantly reduced in B1-/- when compared to WT cells. This result was accompanied by a decreased rate in the L-Arg uptake by B1-/- cells. Incubation with NEM impaired the L-Arg uptake in WT, but had no effect in B1-/- cells. Protein expression and mRNA levels for CAT-1 were reduced in B1-/- in comparison to WT cells. These findings suggest an important role of the endothelial B1 receptor in the vascular control by interfering with CAT-1 expression, L-Arg uptake and NO release.

Gene expression profile of cytokines and receptors of inflammation from cultured keratinocytes of burned patients.

INTRODUCTION: At all stages of wound healing, growth factors and cytokines play a particularly important role in the interaction with keratinocytes cellular receptors. Keratinocytes have received little attention about their potential to act as a source and target of cytokines. Changes in the cytokine levels after the burning occur prior to the metabolic abnormalities. Thus, it may be possible to develop therapeutic interventions that can mitigate the acute inflammatory response and modulating expression of these cytokines. The objective was to evaluate the expression of 84 genes mediators of the inflammatory response by using PCR array in a primary human epidermal cultured keratinocytes from patients with burns. METHODS: Keratinocytes cultured from normal skin around injury from small and large burn patient were treated for DNA synthesis. The samples were analyzed by the PCR Superarray(®) assay and curve analyses were performed for 84 relevant human genes and their involvement in the inflammatory cytokines pathway and receptors. These genes were checked for the up or down regulation. And it was used MetaCore™ for the analysis of networks and Gene Ontology (GO) processes. RESULTS: Chemokines of the CXC family were more expressed in the large burn group, except CXCL12. The C, CC and CX3C chemokine family were downregulated, especially in the small burn group. The interleukins IL8 and IL1B were more expressed in large burn than in small burn; except IL13RA1, IL13 and IL5RA that were downregulated, mainly in the small burn group. CONCLUSIONS: The cytokine profile showed some important differences between the large and small burn patients, and from this original database, we can create new interventional trials in acute inflammation in burns.