Elevated IL-1β levels in anti-Ro/SSA connective tissue diseases patients with prolonged corrected QTc interval.

Objectives: Patients with systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (pSS) have increased IL-1β levels. IL-1β and other pro-inflammatory cytokines have a modulating activity on cardiac ion channels and have been associated with increased arrhythmic risk in rheumatoid arthritis patients. Likewise, adult patients with connective tissue diseases (CTDs) may have prolonged QTc intervals associated with the presence of anti-Ro/SSA antibodies.

Action of anti-M₃muscarinic acetylcholine receptor IgG of primary Sjögren's syndrome on the enzymatic antioxidant system in rat submandibular gland.

Background: We demonstrate that serum immunoglobulin G (IgG) directed against glandular M3 muscarinic acetylcholine receptors (M₃mAChR) and pilocarpine triggers the increment of superoxide dismutase (SOD) and catalase (CAT) and the production of nitric oxide (NO) and prostaglandin E₂(PGE₂).

Methods: Enzyme-linked immunosorbent assay (ELISA) was performed in the presence of the human M₂mAChR synthetic peptide as antigen to detect in serum of pSS patients the autoantibodies. Further, SOD and CAT specific activity and NO were determined chemically in the presence of anti-M₃mAChR IgG and pilocarpine.

Pro-apoptotic effect of anti-β1-adrenergic receptor antibodies in periodontitis patients.

An anti-β(1)-adrenergic antibody from the sera of periodontitis patients (anti-β(1)-AR IgG) against the second extracellular loop of the human β(1)-adrenoceptor (β(1)-AR) has been shown to cause rat atria apoptosis. The anti-β(1)-AR IgG binds and activates atria β(1)-AR, increasing the intracellular calcium concentration, which, in turn, activates caspases-3, -8, and -9. The β(1)-AR and the post-receptor activation of calcium/calmodulin (CaM) lead to increased inducible nitric oxide synthase (iNOS) activity, with an increase in cyclic GMP (cGMP) accumulation as well as increased JNK phosphorylation and cyclic AMP (cAMP) production.

β1-Adrenoceptor antibody-induced increase in soluble CD40 ligand release in chronic periodontitis patients: role of prostaglandin E(2).

In this paper, we demonstrate that circulating antibodies from chronic periodontitis patients reacting with atrial β(1)-adrenoceptors (β(1)-ARs) act as an inducer of soluble CD40 ligand (sCD40L) release and prostaglandin E(2) (PGE(2)) generation. By enzyme-linked immunosorbent assay using β(1) synthetic peptide (with an amino acid sequence identical to the second loop of human myocardial β(1)-ARs) as a coating antigen, we demonstrated reactivity against the second extracellular loop on human myocardial β(1)-ARs. This autoantibody present in the serum of chronic periodontitis patients was significantly correlated with the release of sCD40L and PGE(2).

Anti-M(3) peptide IgG from Sjögren's syndrome triggers apoptosis in A253 cells.

Primary Sjögren's syndrome (pSS) is an autoimmune disease that targets salivary and lachrymal glands, characterized by anti-cholinergic autoantibodies directed against the M(3) muscarinic acetylcholine receptor (mAChR). The aim of this work was to evaluate if cholinergic autoantibodies contained in IgG purified from Sjögren sera could trigger apoptosis of A253 cell line. We also determined if caspase-3 and matrix metalloproteinase-3 (MMP-3) are involved in the induction of A253 cell death.

Atorvastatin inhibits the inflammatory response caused by anti-M(3) peptide IgG in patients with primary Sjögren's syndrome.

Experimental and clinical investigations have revealed that statins can down-regulate acute and chronic inflammatory processes. Whether statins express anti-inflammatory activities in the salivary glands in patients with primary Sjögren's syndrome (pSS) is not known. The in vitro and in vivo effect of atorvastatin on rat submandibular gland treated with anti-M(3) peptide IgG purified from SS patients was studied.

Cholinergic Autoantibodies from Primary Sjögren's Syndrome Inhibit Mucin Production via Phospholipase C and Cyclooxygenase-2 In the Rat Submandibular Gland.

Background: Patients with primary Sjögren's syndrome (pSS) produce functional IgG against cholinoreceptor of exocrine glands modifying their activity. The aim of the present work was to demonstrate pSS IgG antibodies (pSS IgG) interacting with M(3) muscarinic acetylcholine receptors (mAChR) of rats submandibular glands that alter mucin release and production via phospholipase C (PLC) and cyclooxigenase-2 (COX-2) pathways.

Methods: Mucin release and production of prostaglandin E2 (PGE2), and total inositol phosphates (InsP) were measured in rat submandibular gland in the presence of pSS IgG auto antibodies.

Autoantibodies to the β(1)-Adrenoceptor from Patients with Periodontitis as a Risk Factor for Cardiac Dysfunction.

The presence of serum autoantibodies in periodontitis (P) patients against β(1)-adrenoceptor (β(1)-AR), using cardiac membranes or a synthetic β(1)-AR peptide corresponding to the second extracellular loop of human β(1)-AR as antigens, permit us to detect circulating antibody from 40 P patients but not in 20 normal individuals (control). Simultaneously, the P patients exhibited a decrease in HRV. Anti-β(1)-AR IgG titters correlated with the decrease in HRV of the same patients and the anti-β(1)-AR peptide IgG displayed partial agonist-like activity and modified the contractility of isolated atria, produced cyclic nucleotides, and inhibited the β(1)-AR agonistic activity of isoproterenol.

Role of anti-β1 adrenergic antibodies from patients with periodontitis in cardiac dysfunction.

Background: The presence of serum autoantibodies against β(1) adrenoreceptors (β(1)-ARs) in human gingival fibroblast from patients with periodontitis inhibits primary cell-specific growth and induces over-expression of pro-inflammatory mediators. Serum β(1)-AR autoantibodies from patients with periodontitis react with myocardium and modify cardiac contractility. The relationship between the presence of serum β(1)-AR autoantibodies and alterations in heart rate variability (HRV) was also studied.

Anti-M(3) muscarinic cholinergic autoantibodies from patients with primary Sjögren's syndrome trigger production of matrix metalloproteinase-3 (MMP-3) and prostaglandin E(2) (PGE(2)) from the submandibular glands.

Background: We demonstrated that serum immunoglobulin G (IgG) from patients with primary Sjögren's syndrome (pSS), interacting with the second extracellular loop of human glandular M(3) muscarinic acetylcholine receptors (M(3) mAChR), trigger the production of matrix metalloproteinase-3 (MMP-3) and prostaglandin E(2) (PGE(2)).

Methods: Enzyme-linked immunosorbent assays (ELISAs) were performed in the presence of M(3) mAChR synthetic peptide as antigen to detect in serum the autoantibodies. Further, MMP-3 and PGE(2) production were determined in the presence of anti-M(3) mAChR autoantibodies.

Inflammation triggers constitutive activity and agonist-induced negative responses at M(3) muscarinic receptor in dental pulp.

The purpose of this study was to investigate whether the inflammation of rat dental pulp induces the muscarinic acetylcholine receptor (mAChR) constitutive receptor activity. Pulpitis was induced with bacterial lipolysaccharide in rat incisors dental pulp. Saturation assay with [(3)H]-quinuclidinyl benzilate ([(3)H] QNB), competitive binding with different mAChR antagonist subtypes, and nitric oxide synthase (NOS) activity were performed.

Lidocaine-induced apoptosis of gingival fibroblasts: participation of cAMP and PKC activity.

Local anaesthetics are drugs that prevent or relieve pain by interrupting nervous conduction and are the most commonly used drugs in dentistry. Their main targets of action are voltage-dependent Na+ channels. The Na+ channel is modulated by phosphorylation of two enzymes: PKA (protein kinase A) and PKC (protein kinase C).

Cholinergic autoantibodies from primary Sjögren's syndrome modulate submandibular gland Na+/K+-ATPase activity via prostaglandin E2 and cyclic AMP.

We demonstrate that patients with primary Sjögren's syndrome (pSS) produce functional IgG autoantibodies that interact with the glandular M(3) muscarinic acetylcholine receptors (mAChRs). These autoantibodies act as a partial muscarinic agonist, increasing prostaglandin E(2) (PGE(2)) and cyclic AMP production through modifying Na(+)/K(+)-ATPase activity, but also interfere with the secretory effect of the parasympathetic neurotransmitter. The IgG from patients with pSS has two effects on the submandibular gland.

Beta-adrenergic-induced CD40 overexpression on gingival fibroblasts: role of PGE2.

CD40, a member of the tumour necrosis factor-alpha receptor family, is constitutively expressed by cells of haematopoietic and non-haematopoietic origin, including fibroblasts. Signalling through this receptor molecule regulates inflammatory mediator secretion by many cell types. The work has been performed in healthy subjects and the authors studied, by cellular culture, flow cytometric analysis and ELISA assay, the expression of CD40 and PGE2 (prostaglandin E2) generation on gingival fibroblasts stimulated by beta-AR (beta-adrenoceptor) agonists.

Muscarinic cholinoceptor activation by pilocarpine triggers apoptosis in human skin fibroblast cells.

The aim of the present work was to examine the role of muscarinic acetylcholine receptors (mAChRs) on apoptosis in human skin fibroblast cells. Neonatal human skin fibroblast cultures were stimulated with pilocarpine in the presence or absence of specific antagonists. Pilocarpine stimulates apoptosis, total inositol phosphates (InsP) accumulation and nitric oxide synthase (NOS) activity.

Autoantibodies from schizophrenia patients induce cerebral cox-1/iNOS mRNA expression with NO/PGE2/MMP-3 production.

We demonstrated that circulating antibodies from schizophrenia patients, which interact with cerebral M1 muscarinic acetylcholine receptors (M1 mAChRs), trigger production of nitric oxide (NO), prostaglandin E2 (PGE2) and matrix metalloproteinase-3 (MMP-3), and act as inducers of cyclooxygenase-1 (cox-1) and inducible nitric oxide synthase (iNOS) mRNA expression in the rat frontal cortex. The corresponding affinity-purified anti-M1 peptide IgG from schizophrenia patients, while stimulating cerebral M1 mAChRs, increases NOS activity, PGE2 and MMP-3 production associated with iNOS over-activity and mRNA expression. Moreover, PGE2 and MMP-3 production is the result of cox-1 expression and activity.

Circulating beta(1) Adrenergic Autoantibodies from Patients with Chronic Periodontitis Interact with Gingival Fibroblasts.

Objectives: To demonstrate the presence of circulating autoantibodies (Abs) from patients with chronic periodontitis (CP) that interacted with human gingival fibroblast membranes activating beta(1) adrenoceptors (beta(1)-AR).

Methods: Sera and purified IgG from 25 patients with CP and 20 age-matched healthy subjects were studied by flow cytometry, ELISA and DNA synthesis. Human gingival fibroblast membranes and/or synthetic peptides with amino acid sequences identical to human beta(1)-AR were used as antigens.

Experimental periodontitis induces a cAMP-dependent increase in amylase activity in parotid glands from male rats.

It is known that subjects with periodontitis show enhanced amylase concentration in saliva. Our purpose was to analyze the release of amylase in parotid glands from rats with experimental periodontitis and controls. We present evidence that periodontitis induces an increase in resting amylase activity and release without changes in isoproterenol-induced amylase secretion.

Increased leukotriene concentration in submandibular glands from rats with experimental periodontitis.

Objective And Design: In the present study, we investigated the relation between the inflammatory mediators such as nitric oxide, prostaglandins, and cysteinyl-leukotrienes with mucin release and the sympathetic system in submandibular glands from rats with experimental periodontitis.

Materials Or Subjects: Submandibular glands from rats with experimental periodontitis.

Treatment: For the first experiment, rats were treated with hydrocortisone sc, 1 mg/kg for 3 days.

Cholinoceptor modulation on nitric oxide regulates prostaglandin E(2) and metalloproteinase-3 production in experimentally induced inflammation of rat dental pulp.

The purpose of this study was to investigate the role of muscarinic acetylcholine receptor (mAChR) activity in the regulation of inducible nitric oxide synthase (iNOS) activity, prostaglandin E(2) (PGE(2)), and metalloproteinase-3 (MMP-3) in experimentally induced inflammation of rat incisors dental pulp. Inflammation was induced by application of bacterial lipopolysaccharide (LPS) to the pulp. Extirpated pulp tissue samples were incubated in saline solution until the various experiments were performed.

Chagasic antibodies induce cardiac COX-2/iNOS mRNA expression with PGE2/NO production.

We demonstrate that serum IgG in chagasic patients interacting with the second extracellular loop of human cardiac M(2) muscarinic acetylcholine receptors (M(2) mAChR) trigger the production of PGE(2) and NO, that in turn induces COX-2/iNOS mRNA expression. An association between serum anti-M(2) peptide IgG, anti-cardiac membrane IgG and PGE(2) levels (p<0.05) in chagasic dysautonomic patients was observed.

Beta-adrenoceptor alterations coupled with secretory response and experimental periodontitis in rat submandibular glands.

In this paper we have studied the influence of a well-established rat model of periodontitis on resting and adrenergic-stimulated mucin secretion from rat submandibular glands. The selective beta(1)-receptor subtype agonist, dobutamine, induced mucin secretion while the selective beta(2)-, alpha(1)- and alpha(2)-agonists, soterenol, phenylephrine and clonidine, respectively, did not. In rats subjected to ligature-induced periodontitis mucin release, under unstimulated conditions (basal values), was significantly increased.

Anti-brain cholinergic auto antibodies from primary Sjögren syndrome sera modify simultaneously cerebral nitric oxide and prostaglandin biosynthesis.

The presence of circulating antibodies from primary Sjögren Syndrome (pSS) patients enable to interact with rat cerebral frontal cortex by activating muscarinic acetylcholine receptors (mAChR). ELISA assay for PGE2 generation, nitric oxide synthase (NOS) activity was measured in cerebral frontal cortex slices by production of [U-14C]-citruline and mRNA isolation/quantitative PCR for COX-1 and COX-2 gene expression were carried out. By ELISA assay, it was shown that IgG from pSS patients reacted to cerebral frontal cortex cell surface and with human M1 and M3 mAChR.

Differential regulation on human skin fibroblast by alpha1 adrenergic receptor subtypes.

Alpha 1 adrenoceptor (alpha1-AR) regulation of DNA synthesis was studied in human neonatal foreskin fibroblast. Saturation assay with a specific radioligand for alpha1 adrenergic [3H]-prazosin revealed two saturated and specific binding sites with high or low affinity. Competitive binding assay with different antagonist subtypes, defined pharmacologically three major types of alpha1-AR.

Nitric oxide synthase and PGE2 reciprocal interactions in rat dental pulp: cholinoceptor modulation.

In this study we determined the effect of cholinoceptor agonist pilocarpine on the stimulation of nitric oxide synthase (NOS) and on prostaglandin E2 (PGE2) generation upon rat dental pulp. By reverse transcriptase/polymerase chain reaction (RT-PCR) we identified several products corresponding to m1, m2, m3, and m4 muscarinic acetylcholine receptors (mAChRs). The stimulation of M1, M2, M3, and M4 mAChRs by pilocarpine increases NOS activity and PGE2 generation.