The TRPV4 channel is a novel regulator of intracellular Ca2+ in human esophageal epithelial cells

2011 ◽  
Vol 301 (1) ◽  
pp. G138-G147 ◽  
Author(s):  
Takashi Ueda ◽  
Michiko Shikano ◽  
Takeshi Kamiya ◽  
Takashi Joh ◽  
Shinya Ugawa
Keyword(s):  
Cell Proliferation ◽  
Elevated Temperature ◽  
Epithelial Cells ◽  
Cell Viability ◽  
Connexin 43 ◽  
Transient Receptor Potential ◽  
Atp Release ◽  
Transient Receptor Potential Vanilloid ◽  
Dependent Manner ◽  
Esophageal Epithelial Cells

The esophageal epithelium has sensory properties that enable it to sustain normal barrier function. Transient receptor potential vanilloid 4 (TRPV4) is a Ca2+-permeable channel that is activated by extracellular hypotonicity, polyunsaturated fatty acids, phorbol esters, and elevated temperature. We found that TRPV4 is expressed in both human esophageal tissue and in HET-1A cells, a human esophageal epithelial cell line. Specific activation of TRPV4 by the phorbol ester 4α-phorbol 12,13-didecanoate (4α-PDD) increased intracellular Ca2+ in a subset of HET-1A cells. Elevated temperature strongly potentiated this effect at low concentrations of 4α-PDD, and all of the responses were inhibited by the TRPV antagonist ruthenium red. TRPV4 activation differentially affected cell proliferation and cell viability; HET-1A cell proliferation was increased by 1 μM 4α-PDD, whereas higher concentrations (10 μM and 30 μM) significantly decreased cell viability. Transient TRPV4 activation triggered ATP release in a concentration-dependent manner via gap-junction hemichannels, including pannexin 1 and connexin 43. Furthermore, TRPV4 activation for 24 h did not increase the production of interleukin 8 (IL-8) but reduced IL-1β-induced IL-8 production. Small-interference RNA targeted to TRPV4 significantly attenuated all of the 4α-PDD-induced responses in HET-1A cells. Collectively, these findings suggest that TRPV4 is a novel regulator of Ca2+-dependent signaling pathways linked to cell proliferation, cell survival, ATP release, and IL-8 production in human esophageal epithelial cells.

PAR-2 activation enhances weak acid-induced ATP release through TRPV1 and ASIC sensitization in human esophageal epithelial cells

2015 ◽  
Vol 309 (8) ◽  
pp. G695-G702 ◽  
Author(s):  
Liping Wu ◽  
Tadayuki Oshima ◽  
Jing Shan ◽  
Hiroo Sei ◽  
Toshihiko Tomita ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Transient Receptor Potential ◽  
Atp Release ◽  
Receptor Potential ◽  
Weak Acid ◽  
Transient Receptor Potential Vanilloid ◽  
Esophageal Epithelial Cells ◽  
Transient Receptor ◽  
Esophageal Hypersensitivity ◽  
Interfering Rna

Esophageal visceral hypersensitivity has been proposed to be the pathogenesis of heartburn sensation in nonerosive reflux disease. Protease-activated receptor-2 (PAR-2) is expressed in human esophageal epithelial cells and is believed to play a role in inflammation and sensation. PAR-2 activation may modulate these responses through adenosine triphosphate (ATP) release, which is involved in transduction of sensation and pain. The transient receptor potential vanilloid receptor 1 (TRPV1) and acid-sensing ion channels (ASICs) are both acid-sensitive nociceptors. However, the interaction among these molecules and the mechanisms of heartburn sensation are still not clear. We therefore examined whether ATP release in human esophageal epithelial cells in response to acid is modulated by TRPV1 and ASICs and whether PAR-2 activation influences the sensitivity of TRPV1 and ASICs. Weak acid (pH 5) stimulated the release of ATP from primary human esophageal epithelial cells (HEECs). This effect was significantly reduced after pretreatment with 5-iodoresiniferatoxin (IRTX), a TRPV1-specific antagonist, or with amiloride, a nonselective ASIC blocker. TRPV1 and ASIC3 small interfering RNA (siRNA) transfection also decreased weak acid-induced ATP release. Pretreatment of HEECs with trypsin, tryptase, or a PAR-2 agonist enhanced weak acid-induced ATP release. Trypsin treatment led to the phosphorylation of TRPV1. Acid-induced ATP release enhancement by trypsin was partially blocked by IRTX, amiloride, or a PAR-2 antagonist. Conversely, acid-induced ATP release was augmented by PAR-2 activation through TRPV1 and ASICs. These findings suggested that the pathophysiology of heartburn sensation or esophageal hypersensitivity may be associated with the activation of PAR-2, TRPV1, and ASICs.

Oxidative stress-induced posttranslational modification of TRPV1 expressed in esophageal epithelial cells

2011 ◽  
Vol 301 (2) ◽  
pp. G230-G238 ◽  
Author(s):  
Etsuko Kishimoto ◽  
Yuji Naito ◽  
Osamu Handa ◽  
Hitomi Okada ◽  
Katsura Mizushima ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Epithelial Cells ◽  
Posttranslational Modification ◽  
Transient Receptor Potential ◽  
Epithelial Cell Line ◽  
Transient Receptor Potential Vanilloid ◽  
Esophageal Mucosa ◽  
Chemokine Production ◽  
Modified Proteins ◽  
Esophageal Epithelial Cells

Human esophageal epithelium is continuously exposed to physical stimuli or to gastric acid that sometimes causes inflammation of the mucosa. Transient receptor potential vanilloid 1 (TRPV1) is a nociceptive, Ca2+-selective ion channel activated by capsaicin, heat, and protons. It has been reported that activation of TRPV1 expressed in esophageal mucosa is involved in gastroesophageal reflux disease (GERD) or in nonerosive GERD symptoms. In this study, we examined the expression and function of TRPV1 in the human esophageal epithelial cell line Het1A, focusing in particular on the role of oxidative stress. Interleukin-8 (IL-8) secreted by Het1A cells upon stimulation by capsaicin or acid with/without 4-hydroxy-2-nonenal (HNE) was measured by ELISA. Following capsaicin stimulation, the intracellular production of reactive oxygen species (ROS) was determined using a redox-sensitive fluorogenic probe, and ROS- and HNE-modified proteins were determined by Western blotting using biotinylated cysteine and anti-HNE antibody, respectively. HNE modification of TRPV1 proteins was further investigated by immunoprecipitation after treatment with synthetic HNE. Capsaicin and acid induced IL-8 production in Het1A cells, and this production was diminished by antagonists of TRPV1. Capsaicin also significantly increased the production of intracellular ROS and ROS- or HNE-modified proteins in Het1A cells. Moreover, IL-8 production in capsaicin-stimulated Het1A cells was enhanced by synthetic HNE treatment. Immunoprecipitation studies revealed that TRPV1 was modified by HNE in synthetic HNE-stimulated Het1A cells. We concluded that TRPV1 functions in chemokine production in esophageal epithelial cells, and this function may be regulated by ROS via posttranslational modification of TRPV1.

scholarly journals HCl-induced and ATP-dependent upregulation of TRPV1 receptor expression and cytokine production by human esophageal epithelial cells

2012 ◽  
Vol 303 (5) ◽  
pp. G635-G645 ◽  
Author(s):  
Jie Ma ◽  
Annamaria Altomare ◽  
Michele Guarino ◽  
Michele Cicala ◽  
Florian Rieder ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Transient Receptor Potential ◽  
Inflammatory Responses ◽  
Atp Release ◽  
Erosive Esophagitis ◽  
Receptor Expression ◽  
Epithelial Cell Line ◽  
Esophageal Mucosa ◽  
Proinflammatory Mediators ◽  
Esophageal Epithelial Cells

The pathogenesis of gastroesophageal reflux disease (GERD) remains elusive, but recent evidence suggests that early secretion of inflammatory cytokines and chemokines by the mucosa leads to influx of immune cells followed by tissue damage. We previously showed that exposure of esophageal mucosa to HCl causes ATP release, resulting in activation of acetyl-CoA:1- O-alkyl- sn-glycero-3-phosphocholine acetyltransferase (lyso-PAF AT), the enzyme responsible for the production of platelet-activating factor (PAF). In addition, HCl causes release of IL-8 from the esophageal mucosa. We demonstrate that esophageal epithelial cells secrete proinflammatory mediators in response to HCl and that this response is mediated by ATP. Monolayers of the human esophageal epithelial cell line HET-1A were exposed to acidified cell culture medium (pH 5) for 12 min, a total of seven times over 48 h, to simulate the recurrent acid exposure clinically occurring in GERD. HCl upregulated mRNA and protein expression for the acid-sensing transient receptor potential cation channel, subfamily vanilloid member 1 (TRPV1), lyso-PAF AT, IL-8, eotaxin-1, -2, and -3, macrophage inflammatory protein-1α, and monocyte chemoattractant protein-1. The chemokine profile secreted by HET-1A cells in response to repeated HCl exposure parallels similar findings in erosive esophagitis patients. In HET-1A cells, the TRPV1 agonist capsaicin reproduced these findings for mRNA of the inflammatory mediators lyso-PAF AT, IL-8, and eotaxin-1. These effects were blocked by the TRPV1 antagonists iodoresiniferatoxin and JNJ-17203212. These effects were imitated by direct application of ATP and blocked by the nonselective ATP antagonist suramin. We conclude that HCl/TRPV-induced ATP release upregulated secretion of various chemoattractants by esophageal epithelial cells. These chemoattractants are selective for leukocyte subsets involved in acute inflammatory responses and allergic inflammation. The data support the validity of HET-1A cells as a model of the response of the human esophageal mucosa in GERD.

scholarly journals The Olive Leaves Extract Has Anti-Tumor Effects against Neuroblastoma through Inhibition of Cell Proliferation and Induction of Apoptosis

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2178
Author(s):  
Fabio Morandi ◽  
Veronica Bensa ◽  
Enzo Calarco ◽  
Fabio Pastorino ◽  
Patrizia Perri ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Viability ◽  
Cell Cycle Progression ◽  
Treatment Strategies ◽  
Annexin V ◽  
Dependent Manner ◽  
Induction Of Apoptosis ◽  
Dose Dependent

Neuroblastoma (NB) is the most common extra-cranial solid tumor of pediatric age. The prognosis for high-risk NB patients remains poor, and new treatment strategies are desirable. The olive leaf extract (OLE) is constituted by phenolic compounds, whose health beneficial effects were reported. Here, the anti-tumor effects of OLE were investigated in vitro on a panel of NB cell lines in terms of (i) reduction of cell viability; (ii) inhibition of cell proliferation through cell cycle arrest; (iii) induction of apoptosis; and (iv) inhibition of cell migration. Furthermore, cytotoxicity experiments, by combining OLE with the chemotherapeutic topotecan, were also performed. OLE reduced the cell viability of NB cells in a time- and dose-dependent manner in 2D and 3D models. NB cells exposed to OLE underwent inhibition of cell proliferation, which was characterized by an arrest of the cell cycle progression in G0/G1 phase and by the accumulation of cells in the sub-G0 phase, which is peculiar of apoptotic death. This was confirmed by a dose-dependent increase of Annexin V+ cells (peculiar of apoptosis) and upregulation of caspases 3 and 7 protein levels. Moreover, OLE inhibited the migration of NB cells. Finally, the anti-tumor efficacy of the chemotherapeutic topotecan, in terms of cell viability reduction, was greatly enhanced by its combination with OLE. In conclusion, OLE has anti-tumor activity against NB by inhibiting cell proliferation and migration and by inducing apoptosis.

scholarly journals Caffeic Acid Prevented LPS-Induced Injury of Primary Bovine Mammary Epithelial Cells through Inhibiting NF-κB and MAPK Activation

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Mingjiang Liu ◽  
Guoqing Fang ◽  
Shaojie Yin ◽  
Xin Zhao ◽  
Chi Zhang ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cell Viability ◽  
Signaling Pathways ◽  
Caffeic Acid ◽  
Proinflammatory Cytokines ◽  
Mammary Epithelial Cells ◽  
Mammary Epithelial ◽  
Signal Pathways ◽  
Dependent Manner ◽  
Bovine Mammary Epithelial Cells

In our previous study, lipopolysaccharide (LPS) significantly reduced the cell viability of primary bovine mammary epithelial cells (bMEC) leading to cell apoptosis, which were prevented by caffeic acid (CA) through inhibiting NF-κB activation and reducing proinflammatory cytokine expression. While the underlying mechanism remains unclear, here, we determined that LPS induced the extensive microstructural damage of bMEC, especially the mitochondria and endoplasmic reticulum. Then, the obvious reduction of mitochondrial membrane potential and expression changes of apoptosis-associated proteins (Bcl-2, Bax, and casepase-3) indicated that apoptosis signaling through the mitochondria should be responsible for the cell viability decrease. Next, the high-throughput cDNA sequencing (RNA-Seq) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were employed to verify that the MAPK and JAK-STAT signaling pathways also were the principal targets of LPS. Following, the critical proteins (ERK, JNK, p38, and c-jun) of the MAPK signaling pathways were activated, and the release of proinflammatory cytokines (TNF-α, IL-1β, IL-6, and IL-8) regulated by NF-κB and MAPKs was significantly increased, which can promote a cascade of inflammation that induces cell injury and apoptosis. Meanwhile, CA significantly inhibited the activation of MAPKs and the release of proinflammatory cytokines in a dose-dependent manner, which were similar to its effects on the NF-κB activation that we previously published. So we concluded that CA regulates the proteins located in the upstream of multiple cell signal pathways which can reduce the LPS-induced activation of NF-κB and MAPKs, thus weakening the inflammatory response and maintaining cell structure and function, which accordingly inhibit apoptosis.

scholarly journals Inhibitory Effect of Manassantin B Isolated from Saururus chinensis on Skin Heat Aging

Cosmetics ◽  
2020 ◽  
Vol 7 (2) ◽  
pp. 47
Author(s):  
Hwa Sun Ryu ◽  
Jeong-Yeon Choi ◽  
Kyeong-Sun Lee ◽  
Jung-No Lee ◽  
Chun Mong Lee ◽  
...  
Keyword(s):  
Heat Shock ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Skin Aging ◽  
Shock Treatment ◽  
Transient Receptor Potential Vanilloid ◽  
Dependent Manner ◽  
Heat Shock Treatment ◽  
Channel Inhibition ◽  
Saururus Chinensis

Heat shock treatment-induced skin aging causes a thickened epidermis, increased matrix metalloproteinase (MMP)-1 expression, collagen degradation, and deep wrinkles. In this study, we investigated the effect of manassantin B in preventing heat shock treatment-induced aging. We first separated manassantin B (MB) from the roots of Saururus chinensis, and the structure was identified using 1H- and 13C-NMR spectroscopy. RT-PCR and western blotting were applied to investigate the anti-aging effect of manassantin B. Manassantin B decreased MMP-1 expression through transient receptor potential vanilloid (TRPV) 1 channel inhibition and significantly increased procollagen expression. In addition, manassantin B suppressed MAPK phosphorylation in a dose-dependent manner. Our results suggest that manassantin B, the active ingredient in S. chinensis, can be effectively used to inhibit heat shock treatment-induced skin aging.

scholarly journals Cytotoxic Effects of Air Freshener Biocides in Lung Epithelial Cells

2013 ◽  
Vol 8 (9) ◽  
pp. 1934578X1300800
Author(s):  
Jung-Taek Kwon ◽  
Mimi Lee ◽  
Gun-Baek Seo ◽  
Hyun-Mi Kim ◽  
Ilseob Shim ◽  
...  
Keyword(s):  
Dna Damage ◽  
Epithelial Cells ◽  
Cell Viability ◽  
Lung Epithelial Cells ◽  
Ros Generation ◽  
Dependent Manner ◽  
Cytotoxic Effects ◽  
Lung Epithelial ◽  
Dose Dependent ◽  
A549 Lung

This study evaluated the cytotoxicity of mixtures of citral (CTR) and either benzisothiazolinone (BIT, Mix-CTR-BIT) or triclosan (TCS, Mix-CTR-TCS) in human A549 lung epithelial cells. We investigated the effects of various mix ratios of these common air freshener ingredients on cell viability, cell proliferation, reactive oxygen species (ROS) generation, and DNA damage. Mix-CTR-BIT and Mix-CTR-TCS significantly decreased the viability of lung epithelial cells and inhibited cell growth in a dose-dependent manner. In addition, both mixtures increased ROS generation, compared to that observed in control cells. In particular, cell viability, growth, and morphology were affected upon increase in the proportion of BIT or TCS in the mixture. However, comet analysis showed that treatment of cells with Mix-CTR-BIT or Mix-CTR-TCS did not increase DNA damage. Taken together, these data suggested that increasing the content of biocides in air fresheners might induce cytotoxicity, and that screening these compounds using lung epithelial cells may contribute to hazard assessment.

Roles of epidermal growth factor and Na+/H+ exchanger-1 in esophageal epithelial defense against acid-induced injury

2006 ◽  
Vol 290 (4) ◽  
pp. G665-G673 ◽  
Author(s):  
Yasuhiro Fujiwara ◽  
Kazuhide Higuchi ◽  
Takashi Takashima ◽  
Masaki Hamaguchi ◽  
Tsuyoshi Hayakawa ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Epithelial Cells ◽  
Acid Reflux ◽  
Dependent Manner ◽  
Egf Receptors ◽  
Epithelial Proliferation ◽  
Epidermal Growth ◽  
Esophageal Epithelial Cells ◽  
Chronic Esophagitis

Epidermal growth factor (EGF) is predominantly secreted by salivary glands and activates Na+/H+ exchanger-1 (NHE-1), which regulates intracellular pH (pHi). We investigated the roles of EGF and NHE-1 in esophageal epithelial defense against acid using human esophageal epithelial cell lines and a rat chronic esophagitis model. Esophageal epithelial cells were incubated with acidified medium in the absence or presence of EGF. Cell viability and changes in pHi were measured. Chronic acid reflux esophagitis was induced in rats with and without sialoadenectomy. Esophageal lesion index, epithelial proliferation, and expression of EGF receptors and NHE-1 were examined. EGF protected esophageal epithelial cells against acid in a dose-dependent manner, and the cytoprotective effect of EGF was completely blocked by treatment with NHE-1 inhibitors. Tyrosine kinase, calmodulin, and PKC inhibitors significantly inhibited cytoprotection by EGF, whereas MEK, phosphatidylinositol 3-kinase, and PKA inhibitors had no effect. EGF significantly increased pHi recovery after NH4Cl pulse acidification, and this increase in pHi recovery was significantly blocked by inhibitors of calmodulin and PKC. Sialoadenectomy led to an increase in the severity of chronic esophagitis but affected neither epithelial proliferation nor expression of EGF receptors. Expression of NHE-1 mRNA was increased in esophagitis and upregulated in rats with sialoadenectomy. The increasing severity of esophagitis in rats with sialoadenectomy was prevented by exogenous administration of EGF. In conclusion, EGF protects esophageal epithelial cells against acid through NHE activation via Ca2+/calmodulin and the PKC pathway. Deficiency in endogenous EGF is associated with increased severity of esophagitis. EGF and NHE-1 play crucial roles in esophageal epithelial defense against acid.

scholarly journals The nonselective cation channel TRPV4 inhibits angiotensin II receptors

2020 ◽  
Vol 295 (29) ◽  
pp. 9986-9997
Author(s):  
Nicholas W. Zaccor ◽  
Charlotte J. Sumner ◽  
Solomon H. Snyder
Keyword(s):  
Angiotensin Ii ◽  
G Protein ◽  
Transient Receptor Potential ◽  
Trp Channels ◽  
Receptor Potential ◽  
Trp Channel ◽  
Luciferase Assay ◽  
Transient Receptor Potential Vanilloid ◽  
Dependent Manner ◽  
Transient Receptor

G-protein–coupled receptors (GPCRs) are a ubiquitously expressed family of receptor proteins that regulate many physiological functions and other proteins. They act through two dissociable signaling pathways: the exchange of GDP to GTP by linked G-proteins and the recruitment of β-arrestins. GPCRs modulate several members of the transient receptor potential (TRP) channel family of nonselective cation channels. How TRP channels reciprocally regulate GPCR signaling is less well-explored. Here, using an array of biochemical approaches, including immunoprecipitation and fluorescence, calcium imaging, phosphate radiolabeling, and a β-arrestin–dependent luciferase assay, we characterize a GPCR–TRP channel pair, angiotensin II receptor type 1 (AT1R), and transient receptor potential vanilloid 4 (TRPV4), in primary murine choroid plexus epithelial cells and immortalized cell lines. We found that AT1R and TRPV4 are binding partners and that activation of AT1R by angiotensin II (ANGII) elicits β-arrestin–dependent inhibition and internalization of TRPV4. Activating TRPV4 with endogenous and synthetic agonists inhibited angiotensin II–mediated G-protein–associated second messenger accumulation, AT1R receptor phosphorylation, and β-arrestin recruitment. We also noted that TRPV4 inhibits AT1R phosphorylation by activating the calcium-activated phosphatase calcineurin in a Ca2+/calmodulin–dependent manner, preventing β-arrestin recruitment and receptor internalization. These findings suggest that when TRP channels and GPCRs are co-expressed in the same tissues, many of these channels can inhibit GPCR desensitization.

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