Specific Upregulation of TRPC1 and TRPC5 Channels by Mineralocorticoid Pathway in Adult Rat Ventricular Cardiomyocytes

Whereas cardiac TRPC (transient receptor potential canonical) channels and the associated store-operated Ca2+ entry (SOCE) are abnormally elevated during cardiac hypertrophy and heart failure, the mechanism of this upregulation is not fully elucidated but might be related to the activation of the mineralocorticoid pathway. Using a combination of biochemical, Ca2+ imaging, and electrophysiological techniques, we determined the effect of 24-h aldosterone treatment on the TRPCs/Orai-dependent SOCE in adult rat ventricular cardiomyocytes (ARVMs). The 24-h aldosterone treatment (from 100 nM to 1 µM) enhanced depletion-induced Ca2+ entry in ARVMs, as assessed by a faster reduction of Fura-2 fluorescence decay upon the addition of Mn2+ and increased Fluo-4/AM fluorescence following Ca2+ store depletion. These effects were prevented by co-treatment with a specific mineralocorticoid receptor (MR) antagonist, RU-28318, and they are associated with the enhanced depletion-induced N-[4-[3,5-Bis(trifluoromethyl)-1H-pyrazol-1-yl]phenyl]-4-methyl-1,2,3-thiadiazole-5-carboxamide (BTP2)-sensitive macroscopic current recorded by patch-clamp experiments. Molecular screening by qRT-PCR and Western blot showed a specific upregulation of TRPC1, TRPC5, and STIM1 expression at the messenger RNA (mRNA) and protein levels upon 24-h aldosterone treatment of ARVMs, corroborated by immunostaining. Our study provides evidence that the mineralocorticoid pathway specifically promotes TRPC1/TRPC5-mediated SOCE in adult rat cardiomyocytes.

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ATP/UTP activate cation-permeable channels with TRPC3/7 properties in rat cardiomyocytes

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00135.2008 ◽

2008 ◽

Vol 295 (1) ◽

pp. H21-H28 ◽

Cited By ~ 30

Author(s):

Julio Alvarez ◽

Alain Coulombe ◽

Olivier Cazorla ◽

Mehmet Ugur ◽

Jean-Michel Rauzier ◽

...

Keyword(s):

Transient Receptor Potential ◽

Single Channel ◽

Mammalian Species ◽

Receptor Potential ◽

Transient Receptor Potential Channel ◽

Rat Cardiomyocytes ◽

Pipette Solution ◽

Adult Rat ◽

Cationic Current ◽

Ventricular Cardiomyocytes

Extracellular purines and pyrimidines have major effects on cardiac rhythm and contraction. ATP/UTP are released during various physiopathological conditions, such as ischemia, and despite degradation by ectonucleotidases, their interstitial concentrations can markedly increase, a fact that is clearly associated with arrhythmia. In the present whole cell patch-clamp analysis on ventricular cardiomyocytes isolated from various mammalian species, ATP and UTP elicited a sustained, nonselective cationic current, IATP. UDP was ineffective, whereas 2′(3′)- O-(4-benzoylbenzoyl)-ATP was active, suggesting that P2Y2 receptors are involved. IATP resulted from the binding of ATP4− to P2Y2 purinoceptors. IATP was maintained after ATP removal in the presence of guanosine 5′-[γ-thio]triphosphate and was inhibited by U-73122, a PLC inhibitor. Single-channel openings are rather infrequent under basal conditions. ATP markedly increased opening probability, an effect prevented by U-73122. Two main conductance levels of 14 and 23 pS were easily distinguished. Similarly, in fura-2-loaded cardiomyocytes, Mn2+ quenching and Ba2+ influx were significant only in the presence of ATP or UTP. Adult rat ventricular cardiomyocytes expressed transient receptor potential channel TRPC1, -3, -4, and -7 mRNA and the TRPC3 and TRPC7 proteins that coimmunoprecipitated. Finally, the anti-TRPC3 antibody added to the patch pipette solution inhibited IATP. In conclusion, activation of P2Y2 receptors, via a G protein and stimulation of PLCβ, induces the opening of heteromeric TRPC3/7 channels, leading to a sustained, nonspecific cationic current. Such a depolarizing current could induce cell automaticity and trigger the arrhythmic events during an early infarct when ATP/UTP release occurs. These results emphasize a new, potentially deleterious role of TRPC channel activation.

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Transient Receptor Potential Melastatin 2 Enhances Vascular Reactivity During Development of Atherosclerosis in Mice

American Journal of Hypertension ◽

10.1093/ajh/hpaa154 ◽

2021 ◽

Vol 34 (1) ◽

pp. 121-122

Author(s):

Yi-quan Dai ◽

Xiao-xiao Yan ◽

Yi-chen Lin ◽

Hong-yu Chen ◽

Xiao-ru Liu

Keyword(s):

Knockout Mice ◽

Vascular Reactivity ◽

Transient Receptor Potential ◽

Gene Knockout ◽

Receptor Potential ◽

Blood Lipid ◽

Normal Diet ◽

Protein Levels ◽

Transient Receptor Potential Melastatin ◽

Transient Receptor

Abstract Background To investigate the function of transient receptor potential melastatin 2 (TRPM2) in vascular reactivity induced by 5-hydroxytryptamine (5-HT) in the aorta during development of atherosclerosis in mice. Methods Forty mice were randomly divided into 4 groups: C57BL/6J on normal diet (C57 + ND), C57BL/6J on high-fat diet (C57 + HFD), apolipoprotein E gene knockout mice (ApoE−/−) on ND (ApoE−/− + ND), and ApoE−/− on HFD (ApoE−/− + HFD). They were fed with a ND or HFD for 16 weeks. Aortic TRPM2 expression and isometric contractions were analyzed. Results In the ApoE−/− + HFD group, body weight, blood glucose, and blood lipid concentrations were increased, and aortic plaques were developed. Compared with the other 3 groups, aortic TRPM2 mRNA and protein levels were significantly increased in the ApoE−/− + HFD group (P < 0.01). Aortic reactivity to 5-HT was enhanced in ApoE−/− + HFD mice with lower EC50 values. The enhanced reactivity to 5-HT was significantly inhibited by TRPM2 inhibitors, N-p-amylcinnamoyl anthranilic acid (1 µmol/l) and 2-aminoethyl diphenylborinate (10 µmol/l). Conclusions Aortic TRPM2 expression is upregulated in ApoE knockout mice fed with a HFD. Upregulation of TRPM2 enhances 5-HT vascular reactivity during development of atherosclerosis.

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Nifedipine-activated Ca2+ permeability in newborn rat cortical collecting duct cells in primary culture

AJP Cell Physiology ◽

10.1152/ajpcell.2001.280.5.c1193 ◽

2001 ◽

Vol 280 (5) ◽

pp. C1193-C1203 ◽

Cited By ~ 5

Author(s):

Laura Valencia ◽

Michel Bidet ◽

Sonia Martial ◽

Elsa Sanchez ◽

Estela Melendez ◽

...

Keyword(s):

Primary Culture ◽

Transient Receptor Potential ◽

Collecting Duct ◽

Primary Cultures ◽

Receptor Potential ◽

Cortical Collecting Duct ◽

Newborn Rat ◽

Adult Rat ◽

Intracellular Ca ◽

Transient Receptor

To characterize Ca2+ transport in newborn rat cortical collecting duct (CCD) cells, we used nifedipine, which in adult rat distal tubules inhibits the intracellular Ca2+concentration ([Ca2+]i) increase in response to hormonal activation. We found that the dihydropyridine (DHP) nifedipine (20 μM) produced an increase in [Ca2+]i from 87.6 ± 3.3 nM to 389.9 ± 29.0 nM in 65% of the cells. Similar effects of other DHP (BAY K 8644, isradipine) were also observed. Conversely, DHPs did not induce any increase in [Ca2+]i in cells obtained from proximal convoluted tubule. In CCD cells, neither verapamil nor diltiazem induced any rise in [Ca2+]i. Experiments in the presence of EGTA showed that external Ca2+ was required for the nifedipine effect, while lanthanum (20 μM), gadolinium (100 μM), and diltiazem (20 μM) inhibited the effect. Experiments done in the presence of valinomycin resulted in the same nifedipine effect, showing that K+ channels were not involved in the nifedipine-induced [Ca2+]i rise. H2O2also triggered [Ca2+]i rise. However, nifedipine-induced [Ca2+]i increase was not affected by protamine. In conclusion, the present results indicate that 1) primary cultures of cells from terminal nephron of newborn rats are a useful tool for investigating Ca2+transport mechanisms during growth, and 2) newborn rat CCD cells in primary culture exhibit a new apical nifedipine-activated Ca2+ channel of capacitive type (either transient receptor potential or leak channel).

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PDGF stimulates pulmonary vascular smooth muscle cell proliferation by upregulating TRPC6 expression

AJP Cell Physiology ◽

10.1152/ajpcell.00125.2002 ◽

2003 ◽

Vol 284 (2) ◽

pp. C316-C330 ◽

Cited By ~ 256

Author(s):

Ying Yu ◽

Michele Sweeney ◽

Shen Zhang ◽

Oleksandr Platoshyn ◽

Judd Landsberg ◽

...

Keyword(s):

Cell Proliferation ◽

Smooth Muscle ◽

Smooth Muscle Cell ◽

Muscle Cell ◽

Transient Receptor Potential ◽

Cyclopiazonic Acid ◽

Receptor Potential ◽

Protein Levels ◽

Resultant Increase ◽

Transient Receptor

Capacitative Ca2+ entry (CCE) through store-operated Ca2+ (SOC) channels plays an important role in returning Ca2+ to the sarcoplasmic reticulum (SR) and regulating cytosolic free Ca2+concentration ([Ca2+]cyt). A rise in [Ca2+]cyt and sufficient Ca2+ in the SR are required for pulmonary artery smooth muscle cell (PASMC) proliferation. We tested the hypothesis that platelet-derived growth factor (PDGF)-mediated PASMC growth involves upregulation of c-Jun and TRPC6, a transient receptor potential cation channel. In rat PASMC, PDGF (10 ng/ml for 0.5–48 h) phosphorylated signal transducer and activator of transcription (STAT3), increased mRNA and protein levels of c-Jun, and stimulated cell proliferation. PDGF treatment also upregulated TRPC6 expression and augmented CCE, elicited by passive depletion of Ca2+ from the SR using cyclopiazonic acid. Furthermore, overexpression of c-Jun stimulated TRPC6 expression and CCE amplitude in PASMC. Downregulation of TRPC6 using an antisense oligonucleotide specifically for human TRPC6 decreased CCE and inhibited PDGF-mediated PASMC proliferation. These results suggest that PDGF-mediated PASMC proliferation is associated with c-Jun/STAT3-induced upregulation of TRPC6 expression. The resultant increase in CCE raises [Ca2+]cyt, facilitates return of Ca2+ to the SR, and enhances PASMC growth.

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Transient Receptor Potential Vanilloid 4 Activation-Induced Increase in Glycine-Activated Current in Mouse Hippocampal Pyramidal Neurons

Cellular Physiology and Biochemistry ◽

10.1159/000487350 ◽

2018 ◽

Vol 45 (3) ◽

pp. 1084-1096 ◽

Cited By ~ 5

Author(s):

Mengwen Qi ◽

Chunfeng Wu ◽

Zhouqing Wang ◽

Li Zhou ◽

Chen Men ◽

...

Keyword(s):

Protein Kinase ◽

Transient Receptor Potential ◽

Pyramidal Neurons ◽

Receptor Potential ◽

Chloride Ion ◽

Transient Receptor Potential Vanilloid ◽

Patch Clamp Recording ◽

Hippocampal Pyramidal Neurons ◽

Protein Levels ◽

Transient Receptor

Background/Aims: Glycine plays an important role in regulating hippocampal inhibitory/ excitatory neurotransmission through activating glycine receptors (GlyRs) and acting as a co-agonist of N-methyl-d-aspartate-type glutamate receptors. Activation of transient receptor potential vanilloid 4 (TRPV4) is reported to inhibit hippocampal A-type γ-aminobutyric acid receptor, a ligand-gated chloride ion channel. GlyRs are also ligand-gated chloride ion channels and this paper aimed to explore whether activation of TRPV4 could modulate GlyRs. Methods: Whole-cell patch clamp recording was employed to record glycine-activated current (IGly) and Western blot was conducted to assess GlyRs subunits protein expression. Results: Application of TRPV4 agonist (GSK1016790A or 5,6-EET) increased IGly in mouse hippocampal CA1 pyramidal neurons. This action was blocked by specific antagonists of TRPV4 (RN-1734 or HC-067047) and GlyR (strychnine), indicating that activation of TRPV4 increases strychnine-sensitive GlyR function in mouse hippocampal pyramidal neurons. GSK1016790A-induced increase in IGly was significantly attenuated by protein kinase C (PKC) (BIM II or D-sphingosine) or calcium/calmodulin-dependent protein kinase II (CaMKII) (KN-62 or KN-93) antagonists but was unaffected by protein kinase A or protein tyrosine kinase antagonists. Finally, hippocampal protein levels of GlyR α1 α2, α3 and β subunits were not changed by treatment with GSK1016790A for 30 min or 1 h, but GlyR α2, α3 and β subunits protein levels increased in mice that were intracerebroventricularly (icv.) injected with GSK1016790A for 5 d. Conclusion: Activation of TRPV4 increases GlyR function and expression, and PKC and CaMKII signaling pathways are involved in TRPV4 activation-induced increase in IGly. This study indicates that GlyRs may be effective targets for TRPV4-induced modulation of hippocampal inhibitory neurotransmission.

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High glucose reduces expression of podocin in cultured human podocytes by stimulating TRPC6

AJP Renal Physiology ◽

10.1152/ajprenal.00215.2019 ◽

2019 ◽

Vol 317 (6) ◽

pp. F1605-F1611 ◽

Cited By ~ 6

Author(s):

Xiao-Yu Lu ◽

Bing-Chen Liu ◽

Yu-Ze Cao ◽

Chang Song ◽

Hua Su ◽

...

Keyword(s):

High Glucose ◽

Transient Receptor Potential ◽

Morphological Changes ◽

Receptor Potential ◽

Diabetic Rat ◽

Protein Levels ◽

Zonula Occludens ◽

Junction Protein ◽

Zonula Occludens 1 ◽

Transient Receptor

The transient receptor potential canonical 6 (TRPC6) channel and podocin are colocalized in the glomerular slit diaphragm as an important complex to maintain podocyte function. Gain of TRPC6 function and loss of podocin function induce podocyte injury. We have previously shown that high glucose induces apoptosis of podocytes by activating TRPC6; however, whether the activated TRPC6 can alter podocin expression remains unknown. Western blot analysis and confocal microscopy were used to examine both expression levels of TRPC6, podocin, and nephrin and morphological changes of podocytes in response to high glucose. High glucose increased the expression of TRPC6 but reduced the expression of podocin and nephrin, in both cultured human podocytes and type 1 diabetic rat kidneys. The decreased podocin was diminished in TRPC6 knockdown podocytes. High glucose elevated intracellular Ca2+ in control podocytes but not in TRPC6 knockdown podocytes. High glucose also elevated the expression of a tight junction protein, zonula occludens-1, and induced the redistribution of zonula occludens-1 and loss of podocyte processes. These data together suggest that high glucose reduces protein levels of podocin by activating TRPC6 and induces morphological changes of cultured podocytes.

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Cyanidin Increases the Expression of Mg2+ Transport Carriers Mediated by the Activation of PPARα in Colonic Epithelial MCE301 Cells

Nutrients ◽

10.3390/nu11030641 ◽

2019 ◽

Vol 11 (3) ◽

pp. 641 ◽

Cited By ~ 1

Author(s):

Yui Takashina ◽

Aya Manabe ◽

Yoshiaki Tabuchi ◽

Akira Ikari

Keyword(s):

Transient Receptor Potential ◽

Receptor Potential ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

Peroxisome Proliferator Activated Receptor ◽

Black Beans ◽

Protein Levels ◽

Fluorescence Measurements ◽

Transient Receptor Potential Melastatin ◽

Transient Receptor

Mg2+ deficiency may be involved in lifestyle-related diseases, including hypertension, cardiovascular diseases, and diabetes mellitus. Dietary Mg2+ is absorbed in the intestine mediated through transcellular and paracellular pathways. However, there is little research into what factors upregulate Mg2+ absorption. We searched for food constituents that can increase the expression levels of Mg2+ transport carriers using mouse colonic epithelial MCE301 cells. Cyanidin, an anthocyanidin found in black beans and berries, increased the mRNA levels of Mg2+ transport carriers including transient receptor potential melastatin 6 (TRPM6) channel and cyclin M4 (CNNM4). The cyanidin-induced elevation of Mg2+ transport carriers was blocked by GW6471, a peroxisome proliferator-activated receptor α (PPARα) inhibitor, but not by PPARγ, PPARδ, and protein kinase A inhibitors. Cyanidin-3-glucoside showed similar results to cyanidin. Cyanidin increased the protein levels of TRPM6 and CNNM4, which were distributed in the apical and lateral membranes, respectively. The nuclear localization of PPARα and reporter activities of Mg2+ transport carriers were increased by cyanidin, which were inhibited by GW6471. The cyanidin-induced elevation of reporter activity was suppressed by a mutation in a PPAR-response element. Fluorescence measurements using KMG-20, an Mg2+ indicator, showed that Mg2+ influx and efflux from the cells were enhanced by cyanidin, and which were inhibited by GW6471. Furthermore, cyanidin increased paracellular Mg2+ flux without affecting transepithelial electrical resistance. We suggest that cyanidin increases intestinal Mg2+ absorption mediated by the elevation of TRPM6 and CNNM4 expression, and may constitute a phytochemical that can improve Mg2+ deficiency.

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Malathion/Oxon and Lead Acetate Increase Gene Expression and Protein Levels of Transient Receptor Potential Canonical Channel Subunits TRPC1 and TRPC4 in Rat Endothelial Cells of the Blood–Brain Barrier

International Journal of Toxicology ◽

10.1177/1091581812442688 ◽

2012 ◽

Vol 31 (3) ◽

pp. 238-249 ◽

Cited By ~ 8

Author(s):

Pergentino Balbuena ◽

Wen Li ◽

Beverly A. Rzigalinski ◽

Marion Ehrich

Keyword(s):

Gene Expression ◽

Endothelial Cells ◽

Blood Brain Barrier ◽

Transient Receptor Potential ◽

Receptor Potential ◽

Intracellular Free Calcium ◽

Free Calcium ◽

Transient Receptor Potential Canonical ◽

Protein Levels ◽

Transient Receptor

This study examined the effects of malathion and lead on transient receptor potential canonical channel TRPC1/TRPC4 channels in rat brain endothelial cells as a mechanism to explain previously noted blood–brain barrier (BBB) permeability induced by these compounds. Lead, malathion, malaoxon and combinations of these were assessed for protein levels and gene expression of TRPC1/C4 at 2, 4, 8, 16, and 24 hours after exposure. Changes in intracellular free calcium dynamics were also assessed. Compounds increased TRPC1 and TRPC4 protein levels as well as gene expression within 4 hours after exposure. Basal levels of intracellular free calcium were also elevated. Increases in gene and protein expression may be associated with an increase in the numbers of TRP channels, and the increases in intracellular calcium may be associated with activation of such channels. Therefore, upregulation and activation of the TRPC1/TRPC4 may be a mechanism by which these neurotoxicants affect BBB permeability.

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17β-Estradiol Activates Estrogen Receptor β-Signalling and Inhibits Transient Receptor Potential Vanilloid Receptor 1 Activation by Capsaicin in Adult Rat Nociceptor Neurons

Endocrinology ◽

10.1210/en.2008-0278 ◽

2008 ◽

Vol 149 (11) ◽

pp. 5540-5548 ◽

Cited By ~ 49

Author(s):

Shenghong Xu ◽

Ying Cheng ◽

Janet R. Keast ◽

Peregrine B. Osborne

Keyword(s):

Sensory Neurons ◽

Transient Receptor Potential ◽

Receptor Potential ◽

Vanilloid Receptor ◽

Female Rats ◽

Transient Receptor Potential Vanilloid ◽

Adult Rat ◽

Vanilloid Receptor 1 ◽

17Β Estradiol ◽

Transient Receptor

There is mounting evidence that estrogens act directly on the nervous system to affect the severity of pain. Estrogen receptors (ERs) are expressed by sensory neurons, and in trigeminal ganglia, 17β-estradiol can indirectly enhance nociception by stimulating expression and release of prolactin, which increases phosphorylation of the nociceptor transducer transient receptor potential vanilloid receptor 1 (TRPV1). Here, we show that 17β-estradiol acts directly on dorsal root ganglion (DRG) sensory neurons to reduce TRPV1 activation by capsaicin. Capsaicin-induced cobalt uptake and the maximum TRPV1 current induced by capsaicin were inhibited when isolated cultured DRGs neurons from adult female rats were exposed to 17β-estradiol (10–100 nm) overnight. There was no effect of 17β-estradiol on capsaicin potency, TRPV1 activation by protons (pH 6–4), and P2X currents induced by α,β-methylene-ATP. Diarylpropionitrile (ERβ agonist) also inhibited capsaicin-induced TRPV1 currents, whereas propylpyrazole triol (ERα agonist) and 17α-estradiol (inactive analog) were inactive, and 17β-estradiol conjugated to BSA (membrane-impermeable agonist) caused a small increase. TRPV1 inhibition was antagonized by tamoxifen (1 μm), but ICI182870 (10 μm) was a potent agonist and mimicked 17β-estradiol. We conclude that TRPV1 in DRG sensory neurons can be inhibited by a nonclassical estrogen-signalling pathway that is downstream of intracellular ERβ. This affects the vanilloid binding site targeted by capsaicin but not the TRPV1 activation site targeted by protons. These actions could curtail the nociceptive transducer functions of TRPV1 and limit chemically induced nociceptor sensitization during inflammation. They are consistent with clinical reports that female pelvic pain can increase after reductions in circulating estrogens.

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The Nuclear Factor-Kappa B Signaling Pathway is Involved in Transient Receptor Potential Vanilloid 4-Mediated Inflammatory Responses and Neuronal Death in Mice with Pilocarpine-Induced Status Epilepticus

10.21203/rs.3.rs-1029384/v1 ◽

2021 ◽

Author(s):

Dong An ◽

Xiuting Qi ◽

Kunpeng Li ◽

Weixing Xu ◽

Yue Wang ◽

...

Keyword(s):

Status Epilepticus ◽

Signaling Pathway ◽

Transient Receptor Potential ◽

Nuclear Translocation ◽

Inflammatory Responses ◽

Receptor Potential ◽

Neuronal Injury ◽

Transient Receptor Potential Vanilloid ◽

Protein Levels ◽

Transient Receptor

Abstract The blockage of transient receptor potential vanilloid 4 (TRPV4) greatly reduces hippocampal neuronal injury in mice with temporal lobe epilepsy through inhibiting inflammation. NF-κB signaling pathway is activated during epilepsy, leading to enhanced inflammation and neuronal injury. Here, we explored whether TRPV4 blockage could affect the NF-κB pathway in mice with pilocarpine-induced status epilepticus (PISE). Application of a TRPV4 antagonist markedly attenuated the PISE-induced increase in hippocampal HMGB1, TLR4, phospho (p)-IκK (p-IκK), and p-IκBα protein levels, as well as those of cytoplasmic p-NF-κB p65 (p-p65) and nuclear NF-κB p65 and p50; in contrast, the application of GSK1016790A, a TRPV4 agonist, showed similar changes to PISE mice. Administration of the TLR4 antagonist TAK-242 or the NF-κB pathway inhibitor BAY 11-7082 led to a noticeable reduction in the hippocampal protein levels of cleaved IL-1β, IL-6 and TNF, as well as those of cytoplasmic p-p65 and nuclear p65 and p50 in GSK1016790A-injected mice. Finally, administration of either TAK-242 or BAY 11-7082 greatly increased neuronal survival in hippocampal CA1 and CA2/3 regions in GSK1016790A-injected mice. We conclude that TRPV4 activation increases HMGB1 and TLR4 expression, leading to IκK and IκBα phosphorylation and, consequently, NF-κB activation and nuclear translocation. The resulting increase in pro-inflammatory cytokine production is responsible for TRPV4 activation-induced neuronal injury. Meanwhile, blocking TRPV4 can downregulate HMGB1/TLR4/IκK/κBα/NF-κB signaling following PISE onset, an effect that may underlie the neuroprotective ability of TRPV4 blockage in mice with PISE.

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