TITLE:
Modulation of c-Jun NH2-Terminal (JNK) by Cholinergic Autoantibodies from Patients with Sjögren’s Syndrome
AUTHORS:
Enri Borda, Daniela Passafaro, Silvia Reina, Leonor Sterin-Borda
KEYWORDS:
JNK, pSS IgG, Autoantibodies, PGE2, NOS, Carbachol, Cholinergic Antagonists, Enzymatic Inhibitors
JOURNAL NAME:
Pharmacology & Pharmacy,
Vol.2 No.4,
October
18,
2011
ABSTRACT: Background: We wanted to determine (via an immunopharmacological approach) whether the c-Jun NH2 terminal kinase (JNK) cascade is phosphorylated in the submandibular gland by carbachol and cholinergic autoantibodies (IgG) present in the sera of patients with primary Sjögren’s syndrome (pSS) by interaction and activation of salivary gland muscarinic acetylcholine receptors (mAChRs). Methods: The JNK, PGE2 and NOS assays were measured in rat sub- mandibular gland with pSS IgG and carbachol alone or in the presence of different blocker agents. Results: pSS IgG- activated M3 mAChRs stimulated JNK phosphorylation whereas the activation of M1 mAChRs by carbachol stimulated JNK phosphorylation involving calcium-activated mechanism. The intracellular pathway leading to pSS IgG-induced biological effects on JNK activity involved activation of protein kinase C (PKC), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) enzymes. Also, activation of COX-2 and COX-1 by pSS IgG and carbachol-induced PGE2 generation were involved. Conclusion: These results may contribute to better understanding the modulatory role of JNK enzymes by cholinergic autoantibodies from pSS patients acting on mAChR in rat submandibular gland.