RESUMEN
Background: Cholinergic urticaria (CholU), a frequent form of chronic inducible urticaria, is characterized by itchy wheals and angioedema in response to sweating. As of now, the rate and pathophysiological relevance of impaired sweating in patients with CholU are ill-defined. Aim: To assess in CholU patients the rate and extent of impaired sweating and its links to clinical and pathophysiological features of CholU. Patients and methods: We assessed sweating in patients with CholU (n = 13) subjected to pulse-controlled ergometry (PCE) provocation testing. Pre- and post-PCE biopsies of lesional (L) and non-lesional (NL) skin were analyzed for the expression of acetylcholine receptor M3 (CHRM3) and acetylcholine esterase (ACh-E) by quantitative histomorphometry and compared to those of healthy control subjects (HCs). CholU patients were assessed for disease duration and severity as well as other clinical features. Results: Of the 13 patients with CholU, 10 showed reduced sweating in response to PCE provocation, and 3 had severely reduced sweating. Reduced sweating was linked to long disease duration and high disease severity. CholU patients with impaired sweating responses showed reduced sweat gland epithelial expression of CHRM3 and ACh-E. Conclusion: Reduced sweating is common in CholU patients, especially in those with long-standing and severe disease, and it can be severe. Reduced expression of CHRM3 and ACh-E may be the cause or consequence of CholU in patients with impaired sweating, and this should be explored by further studies.
Asunto(s)
Acetilcolinesterasa , Receptor Muscarínico M3 , Glándulas Sudoríparas , Sudoración , Urticaria , Acetilcolina/metabolismo , Acetilcolinesterasa/biosíntesis , Acetilcolinesterasa/metabolismo , Colinérgicos , Humanos , Receptor Muscarínico M3/metabolismo , Receptores Colinérgicos , Glándulas Sudoríparas/metabolismo , Glándulas Sudoríparas/patología , Sudoración/fisiología , Urticaria/complicaciones , Urticaria/metabolismoRESUMEN
Reduced plasma vitamin D (VD) levels may contribute to excessive white adipose tissue, insulin resistance (IR) and dyslipidaemia. We evaluated the effect of chronic oral VD supplementation on adiposity and insulin secretion in monosodium glutamate (MSG)-treated rats. During their first 5 d of life, male neonate rats received subcutaneous injections of MSG (4 g/kg), while the control (CON) group received saline solution. After weaning, groups were randomly distributed into VD supplemented (12 µg/kg; three times/week) and non-supplemented (NS) rats, forming four experimental groups (n 15 rats/group): CON-NS, CON-VD, MSG-NS and MSG-VD. At 76 d of life, rats were submitted to an oral glucose tolerance test (OGTT; 2 g/kg), and at 86 d, obesity, IR and plasma metabolic parameters were evaluated. Pancreatic islets were isolated for glucose-induced insulin secretion (GIIS), cholinergic insulinotropic response and muscarinic 3 receptor (M3R), protein kinase C (PKC) and protein kinase A (PKA) expressions. Pancreas was submitted to histological analyses. VD supplementation decreased hyperinsulinaemia (86 %), hypertriacylglycerolaemia (50 %) and restored insulin sensibility (89 %) in MSG-VD rats, without modifying adiposity, OGTT or GIIS, compared with the MSG-NS group. The cholinergic action was reduced (57 %) in islets from MSG-VD rats, without any change in M3R, PKA or PKC expression. In conclusion, chronic oral VD supplementation of MSG-obese rats was able to prevent hyperinsulinaemia and IR, improving triacylglycerolaemia without modifying adiposity. A reduced cholinergic pancreatic effect, in response to VD, could be involved in the normalisation of plasma insulin levels, an event that appears to be independent of M3R and its downstream pathways.
Asunto(s)
Adiposidad/efectos de los fármacos , Suplementos Dietéticos , Secreción de Insulina/efectos de los fármacos , Vitamina D/farmacología , Vitaminas/farmacología , Animales , Hipotálamo/metabolismo , RatasRESUMEN
AIMS: To investigate the effects of injecting RNA interference (RNAi) lentiviruses targeting the muscarinic 3 (M3 ) receptor gene into the bladder wall on bladder activity in rats with spinal cord injury (SCI). METHODS: Four M3 RNAi lentiviruses were constructed and used to infect primary cultured bladder smooth muscle cells (BSMCs). Western blotting and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were performed to determine the optimal RNAi lentivirus with the highest interference efficiency. Female Wistar rats were subjected spinal cord transection at T9-10 and randomly divided into three groups (n = 8), namely, blank control, negative control, and experimental groups, and injected into the bladder wall with saline, negative control shRNA, and M3 RNAi lentiviruses, respectively, 1 week after spinal cord transection. The normal rats were used as normal control group. Urodynamic parameters and bladder tissues were evaluated in the different groups. RESULTS: An M3 RNAi lentivirus with the highest interference efficiency (78.9%) was constructed and identified. Three weeks after injecting M3 RNAi lentiviruses into the bladder wall, Western blotting and qRT-PCR showed that the M3 receptor was significantly downregulated in the experimental group. Cystometric evaluation suggested that downregulating M3 receptor expression could substantially decrease basal pressure, residual volume, and non-voiding contraction number, increase intercontraction interval, and significantly improve bladder compliance in rats with SCI. CONCLUSION: Injecting RNAi lentiviruses targeting the M3 receptor gene into the bladder wall could effectively inhibit neurogenic detrusor overactivity (NDO) due to SCI. Thus, this approach may be a potential treatment for NDO in SCI.
Asunto(s)
Interferencia de ARN , Receptores Muscarínicos/genética , Traumatismos de la Médula Espinal/complicaciones , Vejiga Urinaria Neurogénica/terapia , Vejiga Urinaria Hiperactiva/terapia , Animales , Femenino , Lentivirus , Ratas , Ratas Wistar , Vejiga Urinaria Neurogénica/etiología , Vejiga Urinaria Hiperactiva/etiología , Urodinámica/efectos de los fármacosRESUMEN
BACKGROUND: Salivary gland (SG) injurious agents are all translated into loss of salivation (xerostomia). An association has been established between activation of innate immunity and SG injury and dysfunction. However, it remains unclear how the secretory epithelia respond by halting saliva production. METHODS: C57BL/6 submandibular glands (SMGs) were acutely challenged using a single dose of the innate immune stimulant: polyinosinic-polycytidylic acid (poly (I:C)). Secretory capacity of the infected SMGs was substantiated by assessing the flow rate in response to pilocarpine stimulation. Depletion of the acute inflammatory cells was achieved by pre-treating mice with RB6-8C5 depletion antibody. Flow cytometry, histology and immunohistochemistry were conducted to verify the immune cell depletion. Epithelial expression of saliva-driving molecules: muscarinic 3 receptor (M3R), aquaporin 5 water channel (AQP5), Na-K-CL-Cotransporter 1 (NKCC1) and transmembrane member 16A (TMEM16A), was characterized using RT-qPCR and immunohistochemistry. Tight junction (TJ) protein; zonula occludens (ZO-1) and basement membrane (BM) protein; and laminin were assessed by immunohistochemistry. RESULTS: Innate immune challenge prompted dysfunction in the exocrine SGs. Dysregulated gene and protein expression of molecules that drive saliva secretion was substantiated. Aberrant expression of TJ and BM proteins followed innate immune activation. Hyposalivation in the current model was independent of myeloperoxidase (MPO)-positive, acute inflammatory cells. CONCLUSIONS: In this study, we developed a novel injury model of the SGs, featuring acute secretory dysfunction and immediate structural disruptions. Our results ruled out the injurious role of aggressively infiltrating inflammatory cells.
Asunto(s)
Inmunidad Innata , Glándulas Salivales/efectos de los fármacos , Glándulas Salivales/inmunología , Glándulas Salivales/lesiones , Salivación , Glándula Submandibular/efectos de los fármacos , Glándula Submandibular/inmunología , Glándula Submandibular/lesiones , Animales , Anoctamina-1/metabolismo , Antígenos Ly/metabolismo , Acuaporina 5/metabolismo , Membrana Basal/metabolismo , Regulación hacia Abajo , Femenino , Regulación de la Expresión Génica , Inmunidad Innata/efectos de los fármacos , Inmunohistoquímica , Laminina/metabolismo , Ratones , Ratones Endogámicos C57BL , Peroxidasa/metabolismo , Pilocarpina/farmacología , Poli I-C/farmacología , Receptores Muscarínicos/metabolismo , Saliva/efectos de los fármacos , Saliva/metabolismo , Conductos Salivales/efectos de los fármacos , Glándulas Salivales/patología , Salivación/efectos de los fármacos , Tasa de Secreción/efectos de los fármacos , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo , Glándula Submandibular/patología , Xerostomía , Proteína de la Zonula Occludens-1/metabolismoRESUMEN
Patients with primary Sjögren's syndrome, a systemic autoimmune disease, have been shown to have serum autoantibodies that react with the muscarinic acetylcholine type 3 receptor (M3R).Primary Sjögren's syndrome is a systemic autoimmune disease. Patients with primary Sjögren's syndrome have been shown to have serum autoantibodies that react with the muscarinic acetylcholine type 3 receptor (M3R). Leukopenia has been reported to be significantly more common in primary Sjögren's syndrome patients who have anti-M3R-autoantibodies in their sera. In this study, we investigated whether these anti-M3R autoantibodies have effects on M3R and MHCI expression in Jurkat T cells. Purified IgG antibodies were isolated from the serum of healthy individuals and primary Sjögren's syndrome patients. Jurkat cell line was used to represent T lymphocytes. In situ immunofluorescence confocal microscopy was used to confirm the binding reactivity of primary Sjögren's syndrome IgG antibodies to M3R. Co-immunoprecipitation and immunofluorescence results suggested a direct interaction between M3R and MHC I. Co-internalization of M3R and MHC I was observed when Jurkat cells were exposed to the primary Sjögren's syndrome IgG, but this primary Sjögren's syndrome IgG-induced co-internalization of M3R and MHC I was prevented by the presence of exogenous IFN-γ. Primary Sjögren's syndrome IgG itself did not affect the viability of Jurkat cells, but Jurkat cells exposed to primary Sjögren's syndrome IgG were observed to undergo significant cell death when co-cultured with primary Natural Killer cells. Our results suggest that anti-M3R autoantibodies in primary Sjögren's syndrome induce downregulation of plasma membrane-resident M3R and MHC class I molecules in leukocytes followed by NK cell-mediated cell death. This mechanism may explain the frequency of leukopenia occurrence in patients with primary Sjögren's syndrome.
Asunto(s)
Autoanticuerpos/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Células Asesinas Naturales/inmunología , Leucocitos/inmunología , Receptor Muscarínico M3/inmunología , Síndrome de Sjögren/inmunología , Adulto , Anciano , Muerte Celular/inmunología , Línea Celular Tumoral , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inmunoglobulina G/inmunología , Inmunoprecipitación , Células Jurkat , Leucopenia/inmunología , Masculino , Microscopía Confocal , Persona de Mediana EdadRESUMEN
The endoplasmic reticulum (ER) forms discrete junctions with the plasma membrane (PM) that play a critical role in the regulation of Ca2+ signaling during cellular bioenergetics, apoptosis and autophagy. We have previously confirmed that acetylcholine can inhibit ER stress and apoptosis after inflammatory injury. However, limited research has focused on the effects of acetylcholine on ER-PM junctions. In this work, we evaluated the structure and function of the supramolecular sodium-calcium exchanger 1 (NCX1)-transient receptor potential canonical 3 (TRPC3)-inositol 1,4,5-trisphosphate receptor 1 (IP3R1) complex, which is involved in regulating Ca2+ homeostasis during inflammatory injury. The width of the ER-PM junctions of human umbilical vein endothelial cells (HUVECs) was measured in nanometres using transmission electron microscopy and a fluorescent probe for Ca2+. Protein-protein interactions were assessed by immunoprecipitation. Ca2+ concentration was measured using a confocal microscope. An siRNA assay was employed to silence specific proteins. Our results demonstrated that the peripheral ER was translocated to PM junction sites when induced by tumour necrosis factor-alpha (TNF-α) and that NCX1-TRPC3-IP3R1 complexes formed at these sites. After down-regulating the protein expression of NCX1 or IP3R1, we found that the NCX1-mediated inflow of Ca2+ and the release of intracellular Ca2+ stores were reduced in TNF-α-treated cells. We also observed that acetylcholine attenuated the formation of NCX1-TRPC3-IP3R1 complexes and maintained calcium homeostasis in cells treated with TNF-α. Interestingly, the positive effects of acetylcholine were abolished by the selective M3AChR antagonist darifenacin and by AMPK siRNAs. These results indicate that acetylcholine protects endothelial cells from TNF-alpha-induced injury, [Ca2+]cyt overload and ER-PM interactions, which depend on the muscarinic 3 receptor/AMPK pathway, and that acetylcholine may be a new inhibitor for suppressing [Ca2+]cyt overload.
Asunto(s)
Inflamación/genética , Receptores de Inositol 1,4,5-Trifosfato/genética , Intercambiador de Sodio-Calcio/genética , Canales Catiónicos TRPC/genética , Factor de Necrosis Tumoral alfa/metabolismo , Acetilcolina/metabolismo , Apoptosis/genética , Calcio/metabolismo , Señalización del Calcio/genética , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico , Homeostasis/genética , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Inflamación/metabolismo , Inflamación/patología , Receptores de Inositol 1,4,5-Trifosfato/química , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , ARN Interferente Pequeño/genética , Intercambiador de Sodio-Calcio/química , Canales Catiónicos TRPC/químicaRESUMEN
Cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride (Cl(-)) channel, which plays an important role in physiological anion and fluid secretion, and is defective in several diseases. Although its activation by PKA and PKC has been studied extensively, its regulation by receptors is less well understood. To study signaling involved in CFTR activation, we measured whole-cell Cl(-) currents in BHK cells cotransfected with GPCRs and CFTR. In cells expressing the M3 muscarinic acetylcholine receptor, the agonist carbachol (Cch) caused strong activation of CFTR through two pathways; the canonical PKA-dependent mechanism and a second mechanism that involves tyrosine phosphorylation. The role of PKA was suggested by partial inhibition of cholinergic stimulation by the specific PKA inhibitor Rp-cAMPS. The role of tyrosine kinases was suggested by Cch stimulation of 15SA-CFTR and 9CA-CFTR, mutants that lack 15 PKA or 9 PKC consensus sequences and are unresponsive to PKA or PKC stimulation, respectively. Moreover the residual Cch response was sensitive to inhibitors of the Pyk2 and Src tyrosine kinase family. Our results suggest that tyrosine phosphorylation acts on CFTR directly and through inhibition of the phosphatase PP2A. Results suggest that PKA and tyrosine kinases contribute to CFTR regulation by GPCRs that are expressed at the apical membrane of intestinal and airway epithelia.