The Journal of pharmacology and experimental therapeutics
-
J. Pharmacol. Exp. Ther. · Oct 2014
Treatment with a heme oxygenase 1 inducer enhances the antinociceptive effects of µ-opioid, δ-opioid, and cannabinoid 2 receptors during inflammatory pain.
The administration of µ-opioid receptor (MOR), δ-opioid receptor (DOR), and cannabinoid 2 receptor (CB2R) agonists attenuates inflammatory pain. We investigated whether treatment with the heme oxygenase 1 (HO-1) inducer, cobalt protoporphyrin IX (CoPP), could modulate the local effects and expression of MOR, DOR, or CB2R during chronic inflammatory pain. In mice with inflammatory pain induced by the subplantar administration of complete Freund's adjuvant, we evaluated the effects of the intraperitoneal administration of 10 mg/kg CoPP on the antiallodynic and antihyperalgesic actions of locally administered MOR (morphine), DOR (DPDPE {[d-Pen(2),d-Pen(5)]-enkephalin}), or CB2R [JWH-015 {(2-methyl-1-propyl-1H-indol-3-yl)-1-naphthalenylmethanone}] agonists and its reversion with the HO-1 inhibitor, tin protoporphyrin IX (SnPP). ⋯ CoPP treatment, apart from inducing the expression of HO-1, also enhanced the expression of MOR, did not alter CB2R, and avoided the decreased expression of DOR induced by inflammatory pain. This study shows that the HO-1 inducer (CoPP) increased the local antinociceptive effects of MOR, DOR, and CB2R agonists during inflammatory pain by altering the peripheral expression of MOR and DOR. Therefore, the coadministration of CoPP with local morphine, DPDPE, or JWH-015 may be a good strategy for the management of chronic inflammatory pain.
-
J. Pharmacol. Exp. Ther. · Oct 2014
The α7 nicotinic receptor agonist ABT-107 decreases L-Dopa-induced dyskinesias in parkinsonian monkeys.
Previous studies in Parkinsonian rats and monkeys have shown that β2-selective nicotinic acetylcholine receptor (nAChR) agonists reduce l-Dopa-induced dyskinesias (LIDs), a serious complication of l-Dopa therapy for Parkinson's disease. Since rodent studies also suggested an involvement of α7 nAChRs in LIDs, we tested the effect of the potent, selective α7 agonist ABT-107 [5-(6-[(3R)-1-azabicyclo[2.2.2]oct-3-yloxy] pyridazin-3-yl)-1H-indole]. MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-lesioned monkeys were gavaged with l-Dopa/carbidopa (10 and 2.5 mg/kg, respectively) twice daily, which resulted in stable LIDs. ⋯ Comparable results were observed in a group of monkeys first treated with ABT-107 and then also given ABT-894. Thus, α7 and β2 nAChR-selective drugs may function via a final common mechanism to reduce LIDs. The present results suggest that drugs targeting either α7 or β2 nAChRs may be useful as antidyskinetic agents in Parkinson's disease.
-
J. Pharmacol. Exp. Ther. · Oct 2014
Therapeutic targeting of SRC kinase in myofibroblast differentiation and pulmonary fibrosis.
Myofibroblasts are effector cells in fibrotic disorders that synthesize and remodel the extracellular matrix (ECM). This study investigated the role of the Src kinase pathway in myofibroblast activation in vitro and fibrogenesis in vivo. The profibrotic cytokine, transforming growth factor β1 (TGF-β1), induced rapid activation of Src kinase, which led to myofibroblast differentiation of human lung fibroblasts. ⋯ Furthermore, the total fibrotic area and expression of α-SMA and ECM proteins were significantly decreased in lungs of AZD0530-treated mice. These results indicate that Src kinase promotes myofibroblast differentiation and activation of lung fibroblasts. Additionally, these studies provide proof-of-concept for targeting the noncanonical TGF-β signaling pathway involving Src kinase as an effective therapeutic strategy for lung fibrosis.