Mepivacaine-induced contraction involves phosphorylation of extracellular signal-regulated kinase through activation of the lipoxygenase pathway in isolated rat aortic smooth muscle

2013 ◽  
Vol 91 (4) ◽  
pp. 285-294 ◽  
Author(s):  
Hyo Min Lee ◽  
Seong-Ho Ok ◽  
Hui-Jin Sung ◽  
So Young Eun ◽  
Hye Jung Kim ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Nordihydroguaiaretic Acid ◽  
Rat Aorta ◽  
Dependent Manner ◽  
Aortic Smooth Muscle ◽  
Extracellular Signal Regulated Kinase ◽  
Erk Phosphorylation ◽  
Extracellular Signal ◽  
Cox 2 ◽  
Isolated Rat

Mepivacaine is an aminoamide local anesthetic with an intermediate duration that intrinsically produces vasoconstriction both in vivo and in vitro. This study investigated the arachidonic acid metabolic pathways involved in mepivacaine-induced contraction, and elucidated the associated cellular mechanism with a particular focus on extracellular signal-regulated kinase (ERK) in endothelium-denuded rat aorta. Isolated rat thoracic aortic rings were suspended for isometric tension recording. Cumulative mepivacaine concentration–response curves were generated in the presence or absence of the following inhibitors: quinacrine dihydrochloride, nordihydroguaiaretic acid, phenidone, AA-861, indomethacin, NS-398, SC-560, fluconazole, PD 98059, and verapamil. Mepivacaine-induced ERK phosphorylation, 5-lipoxygenase (5-LOX) expression, and cyclooxygenase (COX)-2 expression in rat aortic smooth muscle cells were detected by Western blot analysis in the presence or absence of inhibitors. Mepivacaine produced tonic contraction in isolated endothelium-denuded rat aorta. Quinacrine dihydrochloride, nordihydroguaiaretic acid, phenidone, AA-861, NS-398, PD 98059, and verapamil attenuated mepivacaine-induced contraction in a concentration-dependent manner. However, fluconazole had no effect on mepivacaine-induced contraction. PD 98059, quinacrine dihydrochloride, nordihydroguaiaretic acid, AA-861, phenidone, and indomethacin attenuated mepivacaine-induced ERK phosphorylation. Mepivacaine upregulated 5-LOX and COX-2 expression. These results suggest that mepivacaine-induced contraction involves ERK activation, which is primarily mediated by the 5-LOX pathway and in part by the COX-2 pathway.

scholarly journals Preventive Effects of a Kampo Medicine, Kakkonto, on Inflammatory Responses via the Suppression of Extracellular Signal-Regulated Kinase Phosphorylation in Lipopolysaccharide-Treated Human Gingival Fibroblasts

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Hiroyuki Kitamura ◽  
Hiroko Urano ◽  
Toshiaki Ara
Keyword(s):  
Periodontal Disease ◽  
Inflammatory Responses ◽  
Human Gingival Fibroblasts ◽  
Kampo Medicine ◽  
Prostaglandin E ◽  
Gingival Fibroblasts ◽  
Extracellular Signal Regulated Kinase ◽  
Erk Phosphorylation ◽  
Extracellular Signal ◽  
Cox 2

Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal tissues, leading to alveolar bone loss in severe clinical cases. The chemical mediator prostaglandin E2 (PGE2) and cytokines such as interleukin- (IL-)6 and IL-8 have been known to play important roles in inflammatory responses and tissue degradation. In the present study, we investigated the effects of a kampo medicine, kakkonto (TJ-1), on the production of prostaglandin E2 (PGE2), IL-6, and IL-8 by human gingival fibroblasts (HGFs) treated with lipopolysaccharide (LPS) from Porphyromonas gingivalis. Kakkonto concentration dependently suppressed LPS-induced PGE2 production but did not alter basal PGE2 levels. In contrast, kakkonto significantly increased LPS-induced IL-6 and IL-8 production. Kakkonto decreased cyclooxygenase- (COX-)1 activity to approximately 70% at 1 mg/mL but did not affect COX-2 activity. Kakkonto did not affect cytoplasmic phospholipase A2 (cPLA2), annexin1, or LPS-induced COX-2 expression. Kakkonto suppressed LPS-induced extracellular signal-regulated kinase (ERK) phosphorylation, which is known to lead to ERK activation and cPLA2 phosphorylation. These results suggest that kakkonto decreased PGE2 production by inhibition of ERK phosphorylation which leads to inhibition of cPLA2 phosphorylation and its activation. Therefore, kakkonto may be useful to improve gingival inflammation in periodontal disease.

scholarly journals Studies on Shokyo, Kanzo, and Keihi in Kakkonto Medicine on Prostaglandin E2 Production in Lipopolysaccharide-Treated Human Gingival Fibroblasts

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Toshiaki Ara ◽  
Norio Sogawa
Keyword(s):  
Inflammatory Responses ◽  
Human Gingival Fibroblasts ◽  
Prostaglandin E ◽  
Gingival Fibroblasts ◽  
Extracellular Signal Regulated Kinase ◽  
Annexin 1 ◽  
Cytosolic Phospholipase ◽  
Erk Phosphorylation ◽  
Extracellular Signal ◽  
Cox 2

We previously demonstrated that a kampo medicine, kakkonto, decreases lipopolysaccharide- (LPS-) induced prostaglandin E2 (PGE2) production by human gingival fibroblasts. In this study, we examined the herbs constituting kakkonto that exhibit this effect. Shokyo strongly and concentration dependently and kanzo and keihi moderately decreased LPS-induced PGE2 production. Shokyo did not alter cyclooxygenase-2 (COX-2) activity, cytosolic phospholipase A2 (cPLA2), annexin 1 and COX-2 expression, and LPS-induced extracellular signal-regulated kinase (ERK) phosphorylation. Kanzo inhibited COX-2 activity but increased annexin 1 and COX-2 expression and did not alter LPS-induced ERK phosphorylation. Keihi inhibited COX-2 activity and LPS-induced ERK phosphorylation but slightly increased COX-2 expression and did not alter cPLA2 and annexin 1 expression. These results suggest that the mechanism of shokyo is through the inhibition of cPLA2 activity, and that of kanzo and keihi is through the inhibition of COX-2 activity and indirect inhibition of cPLA2 activity. Therefore, it is possible that shokyo and kakkonto are clinically useful for the improvement of inflammatory responses.

Involvement of the extracellular signal-regulated kinase 1/2 signaling pathway in amylin's eating inhibitory effect

2012 ◽  
Vol 302 (3) ◽  
pp. R340-R351 ◽  
Author(s):  
Catarina Soares Potes ◽  
Christina Neuner Boyle ◽  
Peter John Wookey ◽  
Thomas Riediger ◽  
Thomas Alexander Lutz
Keyword(s):  
Area Postrema ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Neuronal Responses ◽  
Extracellular Signal Regulated Kinase ◽  
Erk Phosphorylation ◽  
Extracellular Signal ◽  
Anorectic Effect ◽  
Feeding Trials ◽  
Dose Dependent

Peripheral amylin inhibits eating via the area postrema (AP). Because amylin activates the extracellular-signal regulated kinase 1/2 (ERK) pathway in some tissues, and because ERK1/2 phosphorylation (pERK) leads to acute neuronal responses, we postulated that it may be involved in amylin's eating inhibitory effect. Amylin-induced ERK phosphorylation (pERK) was investigated by immunohistochemistry in brain sections containing the AP. pERK-positive AP neurons were double-stained for the calcitonin 1a/b receptor, which is part of the functional amylin-receptor. AP sections were also phenotyped using dopamine-β-hydroxylase (DBH) as a marker of noradrenergic neurons. The effect of fourth ventricular administration of the ERK cascade blocker U0126 on amylin's eating inhibitory action was tested in feeding trials. The number of pERK-positive neurons in the AP was highest ∼10–15 min after amylin treatment; the effect appeared to be dose-dependent (5–20 μg/kg amylin). A portion of pERK-positive neurons in the AP carried the amylin-receptor and 22% of the pERK-positive neurons were noradrenergic. Pretreatment of rats with U0126 decreased the number of pERK-positive neurons in the AP after amylin injection. U0126 also attenuated the ability of amylin to reduce eating, at least when the animals had been fasted 24 h prior to the feeding trial. Overall, our results suggest that amylin directly stimulates pERK in AP neurons in a time- and dose-dependent manner. Part of the AP neurons displaying pERK were noradrenergic. At least under fasting conditions, pERK was shown to be a necessary part in the signaling cascade mediating amylin's anorectic effect.

PDGF (alpha)-receptor is unresponsive to PDGF-AA in aortic smooth muscle cells from the NG2 knockout mouse

1999 ◽  
Vol 112 (6) ◽  
pp. 905-915 ◽  
Author(s):  
K.A. Grako ◽  
T. Ochiya ◽  
D. Barritt ◽  
A. Nishiyama ◽  
W.B. Stallcup
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Receptor Activation ◽  
Wild Type ◽  
Aortic Smooth Muscle Cells ◽  
Phenotypic Differences ◽  
Aortic Smooth Muscle ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal

A line of null mice has been produced which fails to express the transmembrane chondroitin sulfate proteoglycan NG2. Homozygous NG2 null mice do not exhibit gross phenotypic differences from wild-type mice, suggesting that detailed analyses are required to detect subtle alterations caused by the absence of NG2. Accordingly, dissociated cultures of aortic smooth muscle cells from null mice were compared to parallel cultures from wild-type mice for their ability to proliferate and migrate in response to specific growth factors. Both null and wild-type smooth muscle cells exhibited identical abilities to proliferate and migrate in response to PDGF-BB. In contrast, only the wild-type cells responded to PDGF-AA in both types of assays. NG2 null cells failed to proliferate or migrate in response to PDGF-AA, implying a defect in the signaling cascade normally initiated by activation of the PDGF (alpha)-receptor. In agreement with this idea, activation of the extracellular signal-regulated kinase (ERK) in response to PDGF-AA treatment occured only in wild-type cells. Failure to observe autophosphorylation of the PDGF (alpha)-receptor in PDGF-AA-treated null cells indicates that the absence of NG2 causes a defect in signal transduction at the level of (alpha)-receptor activation.

scholarly journals Pref-1 (Preadipocyte Factor 1) Activates the MEK/Extracellular Signal-Regulated Kinase Pathway To Inhibit Adipocyte Differentiation

2006 ◽  
Vol 27 (6) ◽  
pp. 2294-2308 ◽  
Author(s):  
Kyung-Ah Kim ◽  
Jung-Hyun Kim ◽  
Yuhui Wang ◽  
Hei Sook Sul
Keyword(s):  
Adipocyte Differentiation ◽  
Transmembrane Protein ◽  
Biologically Active ◽  
Soluble Form ◽  
Null Mouse ◽  
Dependent Manner ◽  
Wild Type ◽  
Extracellular Signal Regulated Kinase ◽  
Erk Phosphorylation ◽  
Extracellular Signal

ABSTRACT Preadipocyte factor 1 (Pref-1) is found in preadipocytes but is absent in adipocytes. Pref-1 is made as a transmembrane protein but is cleaved to generate a biologically active soluble form. Although Pref-1 inhibition of adipogenesis has been well studied in vitro and in vivo, the signaling pathway for Pref-1 is not known. Here, by using purified soluble Pref-1 in Pref-1 null mouse embryo fibroblasts (MEF), we show that Pref-1 increases MEK/extracellular signal-regulated kinase (ERK) phosphorylation in a time- and dose-dependent manner. Compared to wild-type MEF, differentiation of Pref-1 null MEF into adipocytes is enhanced, as judged by lipid accumulation and adipocyte marker expression. Both wild-type and Pref-1 null MEF show a transient burst of ERK phosphorylation upon addition of adipogenic agents. Wild-type MEF show a significant, albeit lower, second increase in ERK phosphorylation peaking at day 2. This ERK phosphorylation, corresponding to Pref-1 abundance, is absent during differentiation of Pref-1 null MEF. Prevention of this second increase in ERK1/2 phosphorylation in wild-type MEF by the MEK inhibitor PD98059 or by transient depletion of ERK1/2 via small interfering RNA-enhanced adipocyte differentiation. Furthermore, treatment of Pref-1 null MEF with Pref-1 restores this ERK phosphorylation, resulting in inhibition of adipocyte differentiation primarily by preventing peroxisome proliferator-activated receptor γ2 induction. However, in the presence of PD98059 or depletion of ERK1/2, exogenous Pref-1 cannot inhibit adipocyte differentiation in Pref-1 null MEF. We conclude that Pref-1 activates MEK/ERK signaling, which is required for Pref-1 inhibition of adipogenesis.

scholarly journals Ellagic acid suppresses oxidised low-density lipoprotein-induced aortic smooth muscle cell proliferation: studies on the activation of extracellular signal-regulated kinase 1/2 and proliferating cell nuclear antigen expression

2008 ◽  
Vol 99 (4) ◽  
pp. 709-714 ◽  
Author(s):  
Weng-Cheng Chang ◽  
Ya-Mei Yu ◽  
Su-Yin Chiang ◽  
Chiung-Yao Tseng
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Ellagic Acid ◽  
Proliferating Cell Nuclear Antigen ◽  
Muscle Cells ◽  
Nuclear Antigen ◽  
Aortic Smooth Muscle ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal ◽  
Proliferating Cell

Proliferation of intimal vascular smooth muscle cells is an important component in the development of atherosclerosis. Ellagic acid is a phenolic compound present in fruits (raspberries, blueberries, strawberries) and walnuts. The present study investigated the effect of ellagic acid on the oxidised LDL (ox-LDL)-induced proliferation of rat aortic smooth muscle cells (RASMC). The study found that ellagic acid significantly inhibited ox-LDL-induced proliferation of RASMC and phosphorylation of extracellular signal-regulated kinase (ERK) 1/2.Furthermore, ellagic acid also blocked the ox-LDL-induced (inducible) cell-cycle progression and down regulation of the expression of proliferating cell nuclear antigen (PCNA) in RASMC. Therefore, ellagic acid reduced the amount of ox-LDL-induced proliferation of RASMC via inactivation of the ERK pathway and suppression of PCNA expression. These results may significantly advance the understanding of the role that antioxidants play in the prevention of atherosclerosis.

scholarly journals Oxidized alkyl phospholipids stimulate sodium transport in proximal tubules via PPAR-dependent pathway

2021 ◽  
Author(s):  
Tomohito Mizuno ◽  
Nobuhiko Satoh ◽  
Shoko Horita ◽  
Hiroyuki Tsukada ◽  
Yusuke Sato ◽  
...  
Keyword(s):  
Volume Expansion ◽  
Bicarbonate Transport ◽  
Kidney Cortex ◽  
Peroxisome Proliferator ◽  
Dependent Manner ◽  
Peroxisome Proliferator Activated Receptor ◽  
Ppar Agonist ◽  
Extracellular Signal Regulated Kinase ◽  
Erk Phosphorylation ◽  
Extracellular Signal

The pleiotropic effects of oxidized phospholipids (oxPLs) have been identified. 1-O-hexadecyl-2-azelaoyl-sn-glycero-3-phosphocholine (azPC), an oxPL formed from alkyl phosphatidylcholines, is a potent peroxisome proliferator-activated receptor (PPAR) agonist. Although it has been reported that thiazolidinediones can induce volume expansion by enhancing renal sodium and water retention, the role of azPC, an endogenous PPAR agonist, in renal transport functions is unknown. In the present study, we investigated the effect of azPC on renal proximal tubule (PT) transport using isolated PTs and kidney cortex tissues. We showed that azPC rapidly stimulated Na+/HCO3- cotransporter 1 activity and luminal Na+/H+ exchanger (NHE) activities in a dose-dependent manner, at submicromolar concentrations, in isolated PTs from rats and humans. Additionally, the stimulatory effects were completely blocked by a specific PPAR antagonist, 2-chloro-5-nitro-N-phenylbenzamide (GW9662), and a mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitor, PD98059. Treatment with an siRNA against PPAR significantly suppressed the expression of PPAR mRNA, and it completely blocked the stimulation of both Na+/HCO3- cotransporter 1 and NHE activities by azPC. Moreover, azPC induced extracellular signal-regulated kinase (ERK) phosphorylation in rat and human kidney cortex tissues, and the induced ERK phosphorylation by azPC was completely suppressed by GW9662 and PD98059. These results suggest that azPC stimulates renal PT sodium-coupled bicarbonate transport via the PPAR/MEK/ERK pathway. The stimulatory effects of azPC on PT transport may be partially involved in the development of volume expansion.

Sign in / Sign up

Export Citation Format

Share Document