These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Complementary anti-inflammatory actions of the β₂-adrenoceptor agonist clenbuterol and the glucocorticoid dexamethasone in rat brain.
    Author: Ryan KJ, Griffin EW, Connor TJ.
    Journal: J Neuroimmunol; 2011 Mar; 232(1-2):209-16. PubMed ID: 21035874.
    Abstract:
    Systemic administration of the β(2)-adrenoceptor agonist clenbuterol induces expression of IL-1β and its negative regulators, interleukin-1 receptor antagonist (IL-1ra) and the interleukin-1 type II decoy receptor (IL-1RII) in rat brain. Clenbuterol also increases central expression of the broad spectrum anti-inflammatory cytokine interleukin-10 (IL-10) and its downstream signalling molecule, suppressor of cytokine signalling-3 (SOCS-3). Here we examine the impact of combined treatment with clenbuterol (0.5mg/kg) and the glucocorticoid dexamethasone (1mg/kg) on mRNA expression of IL-1β and the IL-1β-inducible gene iNOS, on IκBα mRNA expression and NFκB activation, and on mRNA expression of the anti-inflammatory molecules IL-1ra, IL-1RII, IL-10 and SOCS-3 in rat cortex, striatum and hippocampus. Dexamethasone inhibited induction of IL-1β and iNOS mRNA expression by clenbuterol in all three brain regions, without altering its ability to induce IL-1ra mRNA expression. In the case of IL-1RII, dexamethasone further augmented clenbuterol-induced IL-1RII mRNA expression in hippocampus and striatum. These data highlight a mechanistic dissociation between the ability of β(2)-adrenoceptor activation to induce expression of IL-1β, and its negative regulators IL-1ra and IL-1RII in the brain. Treatment with either dexamethasone or clenbuterol alone independently induced IκBα mRNA expression, and elicited a concomitant decrease in the DNA binding of NFκB in all three brain regions. In the hippocampus and striatum dexamethasone treatment did not influence the ability of clenbuterol to induce IL-10 mRNA expression. In contrast in the cortex, induction of IL-10 and SOCS-3 mRNA expression by clenbuterol administered in combination with dexamethasone was less than induced by clenbuterol alone. Overall these data indicate that combined treatment with dexamethasone and the β(2)-adrenoceptor agonist clenbuterol elicit complementary anti-inflammatory actions in the CNS. Specifically, dexamethasone inhibits expression of pro-inflammatory cytokines, whereas clenbuterol has the added benefit of promoting expression of anti-inflammatory molecules including IL-1ra, IL-1RII, IL-10 and SOCS-3.
    [Abstract] [Full Text] [Related] [New Search]