676 Type 3 Muscarinic Receptor Deficiency Is Associated With Impaired Paracellular Permeability and Activation of Myosin Light Chain (MLC) 2

2013 ◽  
Vol 144 (5) ◽  
pp. S-123-S-124
Author(s):  
Leon McLean ◽  
Luigi Notari ◽  
Rex Sun ◽  
Jennifer A. Bohl ◽  
Shu Yan ◽  
...  
Keyword(s):  
Muscarinic Receptor ◽  
Light Chain ◽  
Myosin Light Chain ◽  
Paracellular Permeability ◽  
Type 3

scholarly journals The Regulation of Intestinal Mucosal Barrier by Myosin Light Chain Kinase/Rho Kinases

2020 ◽  
Vol 21 (10) ◽  
pp. 3550 ◽  
Author(s):  
Younggeon Jin ◽  
Anthony T. Blikslager
Keyword(s):  
Light Chain ◽  
Myosin Light Chain Kinase ◽  
Myosin Light Chain ◽  
Regulatory Protein ◽  
Intestinal Barrier ◽  
Paracellular Permeability ◽  
Mucosal Barrier ◽  
Junctional Complex ◽  
Gastrointestinal Disorders ◽  
Apical Junctional Complex

The intestinal epithelial apical junctional complex, which includes tight and adherens junctions, contributes to the intestinal barrier function via their role in regulating paracellular permeability. Myosin light chain II (MLC-2), has been shown to be a critical regulatory protein in altering paracellular permeability during gastrointestinal disorders. Previous studies have demonstrated that phosphorylation of MLC-2 is a biochemical marker for perijunctional actomyosin ring contraction, which increases paracellular permeability by regulating the apical junctional complex. The phosphorylation of MLC-2 is dominantly regulated by myosin light chain kinase- (MLCK-) and Rho-associated coiled-coil containing protein kinase- (ROCK-) mediated pathways. In this review, we aim to summarize the current state of knowledge regarding the role of MLCK- and ROCK-mediated pathways in the regulation of the intestinal barrier during normal homeostasis and digestive diseases. Additionally, we will also suggest potential therapeutic targeting of MLCK- and ROCK-associated pathways in gastrointestinal disorders that compromise the intestinal barrier.

scholarly journals miR-200b inhibits TNF-α-induced IL-8 secretion and tight junction disruption of intestinal epithelial cells in vitro

2017 ◽  
Vol 312 (2) ◽  
pp. G123-G132 ◽  
Author(s):  
Yujie Shen ◽  
Min Zhou ◽  
Junkai Yan ◽  
Zizhen Gong ◽  
Yongtao Xiao ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Light Chain ◽  
Myosin Light Chain Kinase ◽  
Myosin Light Chain ◽  
Intestinal Epithelial Cells ◽  
Paracellular Permeability ◽  
Intestinal Epithelial ◽  
Tnf Α ◽  
Epithelial Inflammation

Inflammatory bowel diseases (IBDs) are chronic, inflammatory disorders of the gastrointestinal tract with unclear etiologies. Intestinal epithelial cells (IECs), containing crypt and villus enterocytes, occupy a critical position in the pathogenesis of IBDs and are a major producer of immunoregulatory cytokines and a key component of the intact epithelial barrier. Previously, we have reported that miR-200b is involved in the progression of IBDs and might maintain the integrity of the intestinal epithelial barrier via reducing the loss of enterocytes. In this study, we further investigated the impact of miR-200b on intestinal epithelial inflammation and tight junctions in two distinct differentiated states of Caco-2 cells after TNF-α treatment. We demonstrated that TNF-α-enhanced IL-8 expression was decreased by microRNA (miR)-200b in undifferentiated IECs. Simultaneously, miR-200b could alleviate TNF-α-induced tight junction (TJ) disruption in well-differentiated IECs by reducing the reduction in the transepithelial electrical resistance (TEER), inhibiting the increase in paracellular permeability, and preventing the morphological redistribution of the TJ proteins claudin 1 and ZO-1. The expression levels of the JNK/c-Jun/AP-1 and myosin light chain kinase (MLCK)/phosphorylated myosin light chain (p-MLC) pathways were attenuated in undifferentiated and differentiated enterocytes, respectively. Furthermore, a dual-luciferase reporter gene detection system provided direct evidence that c-Jun and MLCK were the specific targets of miR-200b. Collectively, our results highlighted that miR-200b played a positive role in IECs via suppressing intestinal epithelial IL-8 secretion and attenuating TJ damage in vitro, which suggested that miR-200b might be a promising strategy for IBD therapy. NEW & NOTEWORTHY This was the first time that the inhibitory role of miR-200b on intestinal epithelial inflammation and paracellular permeability has been reported. Moreover, we further divided the intestinal epithelial cells (IECs) into two differentiated conditions and investigated the distinct impacts of miR-200b. Finally, we put forward and proved that myosin light chain kinase (MLCK) was a novel target of miR-200b.

Acute stress-induced hypersensitivity to colonic distension depends upon increase in paracellular permeability: role of myosin light chain kinase

Pain ◽  
2005 ◽  
Vol 113 (1) ◽  
pp. 141-147 ◽  
Author(s):  
Afifa Ait-Belgnaoui ◽  
Sylvie Bradesi ◽  
Jean Fioramonti ◽  
Vassilia Theodorou ◽  
Lionel Bueno
Keyword(s):  
Light Chain ◽  
Myosin Light Chain Kinase ◽  
Myosin Light Chain ◽  
Acute Stress ◽  
Paracellular Permeability ◽  
Colonic Distension

Expression of a mutant myosin light chain that cannot be phosphorylated increases paracellular permeability

1997 ◽  
Vol 272 (2) ◽  
pp. F214-F221 ◽  
Author(s):  
S. Gandhi ◽  
D. D. Lorimer ◽  
P. de Lanerolle
Keyword(s):  
Western Blot ◽  
Light Chain ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Myosin Light Chain ◽  
Atp Hydrolysis ◽  
Rat Aorta ◽  
Paracellular Permeability ◽  
Mutant Form ◽  
Dna Encoding

A murine leukemia retroviral vector was engineered to contain the DNA encoding either the wild-type, rat aorta 20-kDa myosin light chain (MLC20) or a mutant form of MLC20 in which Thr18 and Ser19 were mutated into alanines. These mutations result in a MLC20 that cannot be phosphorylated by myosin light chain kinase. An 11-amino acid epitope from c-myc was added to both MLC20 sequences to facilitate identification of these proteins. Madin-Darby canine kidney cells were stably transduced, and MLC20 expression was demonstrated by Western blot analysis using a myc-specific antibody. MLC20 exchange was demonstrated by purifying myosin from the transduced cells and repeating the Western blot analysis. Actin-activated adenosinetriphosphatase assays on the purified myosins demonstrated approximately 50% decrease in the rate of ATP hydrolysis by the myosin containing the mutant MLC20. Transepithelial electrical resistance was decreased and mannitol flux was increased across monolayers of cells expressing mutant MLC20. These data demonstrate that MLC20 phosphorylation is involved in regulating paracellular permeability and epithelial barrier function.

scholarly journals Cyclic Adenosine Monophosphate, Inositol 1,4,5-trisphosphate, Calcium, and Phosphorylated Myosin Light Chain Regulation Through M2 and M3 Muscarinic Receptors of Scleral Fibroblast Cells in Rat Myopia Model

2021 ◽  
Vol 9 (B) ◽  
pp. 890-899
Author(s):  
Nanda Wahyu Anandita ◽  
Nurdiana Nurdiana ◽  
Endang Sri Wahyuni ◽  
Hidayat Sujuti
Keyword(s):  
Animal Models ◽  
Muscarinic Receptor ◽  
Light Chain ◽  
Rattus Norvegicus ◽  
Myosin Light Chain ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Fibroblast Cells ◽  
Inositol 1,4,5 Trisphosphate ◽  
M3 Muscarinic Receptor

AIM: This study aims to investigate the concentration of cyclic adenosine monophosphate (cAMP), inositol 1,4,5-trisphosphate (IP3), calcium (Ca2+), and the expression phosphorylated myosin light chain (MLC) in Rattus norvegicus scleral fibroblast cells. METHODOLOGY: This study utilized an in vitro experimental study by applying Rattus norvegicus scleral fibroblast cell culture. The cultured cells were divided into control and lens-induced myopia (LIM) groups. The control and LIM culture groups were each divided into five groups, namely, negative control, 0.1 μM acetylcholine, 0.1 μM himbacine, 0.1 μM methoctramine, and 0.1 μM 4-DAMP group. The cAMP, IP3, and Ca2+ concentration were analyzed in the 0th, 5th, 10th, 20th, and 30th. The phosphorylated MLC expression was analyzed using confocal microscope. RESULTS: In the LIM group, the highest cAMP concentration is visible at the 10th min on the himbacine group (0.304 ± 0; p = 0.043) and on the 4-DAMP group (0.346 ± 0; p = 0.043). The highest IP3 concentration is found on the LIM group at the 20th min in comparison to the control group (2503.6 ± 11 vs. 2039.2 ± 2.1; p = 0.046). The highest Ca2+ concentration belongs to the 4-DAMP treatment group from the 5th to the 30th min. The highest average phosphorylated MLC expression value in the LIM group is shown by the 0.1μM 4-DAMP treatment (184.2 ± 37.9c au). CONCLUSION: The regulation of cAMP, IP3, Ca2+, and phosphorylated MLC on the M2 and M3 muscarinic receptor of the scleral fibroblast cells of myopia animal models differs from normal animal models which may be due to interactions of M2 and M3 muscarinic receptor as compensation reaction or crosstalk on myopia induction.

Ionomycin and PDBU increase MDCK monolayer permeability independently of myosin light chain phosphorylation

1995 ◽  
Vol 269 (2) ◽  
pp. L144-L150 ◽  
Author(s):  
D. M. Shasby ◽  
J. M. Kamath ◽  
A. B. Moy ◽  
S. S. Shasby
Keyword(s):  
Light Chain ◽  
Mdck Cell ◽  
Myosin Light Chain ◽  
Mdck Cells ◽  
Paracellular Permeability ◽  
Cell Monolayers ◽  
Monolayer Permeability ◽  
Mlc Phosphorylation ◽  
Actomyosin Contraction ◽  
Darby Canine Kidney

It has been hypothesized that modulation of epithelial paracellular permeability may be mediated by initiation of contraction of a band of actin and myosin located at the tight junction. Phosphorylation of myosin light chain (MLC) is an important determinant of actomyosin contraction. We asked if ionomycin (iono) and phorbol 12,13-dibutyrate (PDBU), which increase paracellular permeability of Madin-Darby canine kidney (MDCK) cell monolayers, increased MLC phosphorylation in MDCK cells. MDCK cell MLC was constitutively phosphorylated by myosin light chain kinase (MLCK), and after PDBU and iono > 99% of MLC continued to be phosphorylated by MLCK. Neither iono or PDBU, nor the combination of iono and PDBU, increased MLC phosphorylation. In contrast, the phosphatase inhibitor okadaic acid did increase MLC phosphorylation. Adenosine 3',5'-cyclic monophosphate (cAMP) and forskolin decreased MLC phosphorylation in control MDCK cells and in cells exposed to iono and PDBU. In contrast, cAMP and forskolin did not blunt the decrease in transepithelial resistance caused by iono and PDBU. Iono and PDBU increase MDCK monolayer permeability independently of an increase in MLC phosphorylation.

165: Myosin Light Chain Dephosphorylation is Associated with Bladder Compliance

2006 ◽  
Vol 175 (4S) ◽  
pp. 53-53
Author(s):  
Andy Y. Chang ◽  
Stephen A. Zderic ◽  
Douglas A. Canning ◽  
Samuel Chacko
Keyword(s):  
Light Chain ◽  
Myosin Light Chain ◽  
Bladder Compliance
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