1.Functional roles of sodium-calcium exchange in autorhythmicity and action potential of murine fetal cardiomyocytes at early developmental stage.
Hong-Yan LUO ; Xin-Wu HU ; Liang-Pin ZHANG ; Ying ZENG ; Xiu-Wen GUAN
Acta Physiologica Sinica 2020;72(6):757-764
The aim of the present paper was to study the role of sodium calcium exchanger (NCX) in the generation of action potentials (APs) in cardiomyocytes during early developmental stage (EDS). The precisely dated embryonic hearts of C57 mice were dissected and enzymatically dissociated to single cells. The changes of APs were recorded by whole-cell patch-clamp technique before and after administration of NCX specific blockers KB-R7943 (5 μmol/L) and SEA0400 (1 μmol/L). The results showed that, both KB-R7943 and SEA0400 had potent negative chronotropic effects on APs of pacemaker-like cells, while such effects were only observed in some ventricular-like cardiomyocytes. The negative chronotropic effect of KB-R7943 on ventricular-like cardiomyocytes was accompanied by shortening of AP duration (APD), whereas such an effect of SEA0400 was paralleled by decrease in velocity of diastolic depolarization (Vdd). From embryonic day 9.5 (E9.5) to E10.5, the negative chronotropic effects of KB-R7943 and SEA0400 on ventricular-like APs of embryonic cardiomyocytes gradually disappeared. These results suggest that, in the short-term development of early embryo, the function of NCX may experience developmental changes as evidenced by different roles of NCX in autorhythmicity and APs generation, indicating that NCX function varies with different conditions of cardiomyocytes.
Action Potentials
;
Animals
;
Calcium/metabolism*
;
Mice
;
Myocytes, Cardiac/metabolism*
;
Sodium/metabolism*
;
Sodium-Calcium Exchanger
;
Thiourea/pharmacology*
2.SPA0355 prevents ovariectomy-induced bone loss in mice.
Sang Hoon KIM ; Zhongkai ZHANG ; Young Jae MOON ; Il Woon PARK ; Yong Gon CHO ; Raok JEON ; Byung Hyun PARK
The Korean Journal of Physiology and Pharmacology 2019;23(1):47-54
Estrogen withdrawal in post-menopausal women leads to overactivation of osteoclasts, which contributes to the development of osteoporosis. Inflammatory cytokines are known as one of mechanisms of osteoclast activation after estrogen deficiency. SPA0355 is a thiourea derivative that has been investigated for its antioxidant and anti-inflammatory activities. However, its efficacy in bone resorption has not been previously investigated. The aim of this study was to investigate the impact of SPA0355 on the development of osteoporosis and to explore its mode of action. In vitro experiments showed that SPA0355 inhibited receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis in primary bone marrow-derived macrophages. This effect appears to be independent of estrogen receptor activation as ICI 180,782 failed to abrogate its effects on osteoclasts. Further signaling studies revealed that SPA0355 suppressed activation of the MAPKs, Akt, and NF-κB pathways. SPA0355 also increased osteoblastic differentiation, as evidenced by its effects on alkaline phosphatase activity and mineralization nodule formation. Intraperitoneal administration of SPA0355 to ovariectomized mice prevented bone loss, as verified by three-dimensional images and bone morphometric parameters derived from µCT analysis. Noticeably, SPA0355 did not show hepatotoxicity and nephrotoxicity and also had little effect on hematological parameters. Taken together, the results indicate that SPA0355 may protect against bone loss in ovariectomized mice by stimulation of osteoblast differentiation and by inhibition of osteoclast resorption. Therefore, SPA0355 is a safe and potential candidate for management of postmenopausal osteoporosis.
Alkaline Phosphatase
;
Animals
;
Bone Resorption
;
Cytokines
;
Estrogens
;
Female
;
Humans
;
Imaging, Three-Dimensional
;
In Vitro Techniques
;
Macrophages
;
Mice*
;
Miners
;
Osteoblasts
;
Osteoclasts
;
Osteoporosis
;
Osteoporosis, Postmenopausal
;
Ovariectomy
;
Thiourea
3.Histamine Excites Rat GABAergic Ventral Pallidum Neurons via Co-activation of H1 and H2 Receptors.
Miao-Jin JI ; Xiao-Yang ZHANG ; Xiao-Chun PENG ; Yang-Xun ZHANG ; Zi CHEN ; Lei YU ; Jian-Jun WANG ; Jing-Ning ZHU
Neuroscience Bulletin 2018;34(6):1029-1036
The ventral pallidum (VP) is a crucial component of the limbic loop of the basal ganglia and participates in the regulation of reward, motivation, and emotion. Although the VP receives afferent inputs from the central histaminergic system, little is known about the effect of histamine on the VP and the underlying receptor mechanism. Here, we showed that histamine, a hypothalamic-derived neuromodulator, directly depolarized and excited the GABAergic VP neurons which comprise a major cell type in the VP and are responsible for encoding cues of incentive salience and reward hedonics. Both postsynaptic histamine H1 and H2 receptors were found to be expressed in the GABAergic VP neurons and co-mediate the excitatory effect of histamine. These results suggested that the central histaminergic system may actively participate in VP-mediated motivational and emotional behaviors via direct modulation of the GABAergic VP neurons. Our findings also have implications for the role of histamine and the central histaminergic system in psychiatric disorders.
Action Potentials
;
drug effects
;
Animals
;
Basal Forebrain
;
cytology
;
Dimaprit
;
pharmacology
;
Dose-Response Relationship, Drug
;
Electric Stimulation
;
Female
;
GABAergic Neurons
;
drug effects
;
Histamine
;
pharmacology
;
Histamine Agonists
;
pharmacology
;
Lysine
;
analogs & derivatives
;
metabolism
;
Male
;
Patch-Clamp Techniques
;
Pyridines
;
pharmacology
;
Rats
;
Rats, Sprague-Dawley
;
Receptors, Histamine H1
;
metabolism
;
Receptors, Histamine H2
;
metabolism
;
Sodium Channel Blockers
;
pharmacology
;
Tetrodotoxin
;
pharmacology
;
gamma-Aminobutyric Acid
;
metabolism
4.The Effect of Fungicides on Mycelial Growth and Conidial Germination of the Ginseng Root Rot Fungus, Cylindrocarpon destructans.
Jong Hwan SHIN ; Teng FU ; Kyeong Hun PARK ; Kyoung Su KIM
Mycobiology 2017;45(3):220-225
Ginseng root rot caused by Cylindrocarpon destructans is the most destructive disease of ginseng. Six different fungicides (thiophanate-methyl, benomyl, prochloraz, mancozeb, azoxystrobin, and iprodione) were selected to evaluate the inhibitory effect on the mycelial growth and conidial germination of C. destructans isolates. Benomyl and prochloraz were found to be the most effective fungicides in inhibiting mycelial growth of all tested isolates, showing 64.7% to 100% inhibition at a concentration of 10 µg/mL, whereas thiophanate-methyl was the least effective fungicide, showing less than 50% inhibition even at a higher concentration of 100 µg/mL. The tested fungicides exhibited less than 20% inhibition of conidium germination at concentrations of 0.01, 0.1, and 1 µg/mL. However, the inhibition effect of mancozeb on condium germination of C. destructans was significantly increased to 92% to 99% at a higher concentration of 100 µg/mL, while the others still showed no higher than 30% inhibition.
Benomyl
;
Fungi*
;
Germination*
;
Panax*
;
Spores, Fungal
;
Thiophanate
5.The Bitter Taste Receptor Agonist Quinine Reduces Calorie Intake and Increases the Postprandial Release of Cholecystokinin in Healthy Subjects.
Paolo ANDREOZZI ; Giovanni SARNELLI ; Marcella PESCE ; Francesco P ZITO ; Alessandra D'ALESSANDRO ; Viviana VERLEZZA ; Ilaria PALUMBO ; Fabio TURCO ; Katherine ESPOSITO ; Rosario CUOMO
Journal of Neurogastroenterology and Motility 2015;21(4):511-519
BACKGROUND/AIMS: Bitter taste receptors are expressed throughout the digestive tract. Data on animals have suggested these receptors are involved in the gut hormone release, but no data are available in humans. Our aim is to assess whether bitter agonists influence food intake and gut hormone release in healthy subjects. METHODS: Twenty healthy volunteers were enrolled in a double-blind cross-over study. On 2 different days, each subject randomly received an acid-resistant capsule containing either placebo or 18 mg of hydrochloride (HCl) quinine. After 60 minutes, all subjects were allowed to eat an ad libitum meal until satiated. Plasma samples were obtained during the experiment in order to evaluate cholecystokinin (CCK) and ghrelin levels. Each subject was screened to determine phenylthiocarbamide (PTC) tasting status. RESULTS: Calorie intake was significantly lower when subjects received HCl quinine than placebo (514 +/- 248 vs 596 +/- 286 kcal; P = 0.007). Significantly higher CCK DeltaT90 vs T0 and DeltaT90 vs T60 were found when subjects received HCl quinine than placebo (0.70 +/- 0.69 vs 0.10 +/- 0.86 ng/mL, P = 0.026; 0.92 +/- 0.75 vs 0.50 +/- 0.55 ng/mL, P = 0.033, respectively). PTC tasters ingested a significantly lower amount of calories when they received HCl quinine compared to placebo (526 +/- 275 vs 659 +/- 320 kcal; P = 0.005), whereas no significant differences were found for PTC non-tasters (499 +/- 227 vs 519 +/- 231 kcal; P = 0.525). CONCLUSIONS: This study showed that intra-duodenal release of a bitter compound is able to significantly affect calorie intake and CCK release after a standardized meal. Our results suggest that bitter taste receptor signaling may have a crucial role in the control of food intake.
Animals
;
Cholecystokinin*
;
Cross-Over Studies
;
Eating
;
Gastrointestinal Tract
;
Ghrelin
;
Healthy Volunteers
;
Humans
;
Meals
;
Phenylthiourea
;
Plasma
;
Quinine*
6.Does Measurement of Esophagogastric Junction Distensibility by EndoFLIP Predict Therapy-responsiveness to Endoluminal Fundoplication in Patients With Gastroesophageal Reflux Disease?.
Fabienne G M SMEETS ; Daniel KESZTHELYI ; Nicole D BOUVY ; Ad A M MASCLEE ; Jose M CONCHILLO
Journal of Neurogastroenterology and Motility 2015;21(2):255-264
BACKGROUND/AIMS: In patients with gastroesophageal reflux disease (GERD), an increased esophagogastric junction (EGJ) distensibility has been described. Assessment of EGJ distensibility with the endoscopic functional luminal imaging probe (EndoFLIP) technique might identify patients responsive to transoral incisionless fundoplication (TIF), whereas postoperative measurement of EGJ distensibility might provide insight into the antireflux mechanism of TIF. Therefore, we investigated the value of the EndoFLIP technique in GERD patients treated by TIF. METHODS: Forty-two GERD patients underwent EGJ distensibility measurement before TIF using the EndoFLIP technique. In a subgroup of 25 patients, EndoFLIP measurement was repeated both postoperative and at 6 months follow-up. Treatment outcome was assessed according to esophageal acid exposure time (AET; objective outcome) and symptom scores (clinical outcome) 6 months after TIF. RESULTS: Multiple logistic regression analysis showed that preoperative EGJ distensibility (OR, 0.16; 95% CI, 0.03-0.78; P = 0.023) and preoperative AET (OR, 0.62; 95% CI, 0.42-0.90; P = 0.013) were independent predictors for objective treatment outcome but not for clinical outcome after TIF. The best cut-off value for objective outcome was 2.3 mm2/mmHg for preoperative EGJ distensibility and 11% for preoperative AET. EGJ distensibility decreased direct postoperative from 2.0 (1.2-3.3) to 1.4 (1.0-2.2) mm2/mmHg (P = 0.014), but increased to 2.2 (1.5-3.0) at 6 months follow-up (P = 0.925, compared to preoperative). CONCLUSIONS: Preoperative EGJ distensibility and preoperative AET were independent predictors for objective treatment outcome but not for clinical outcome after TIF. According to our data, the EndoFLIP technique has no added value either in the preoperative diagnostic work-up or in the post-procedure evaluation of endoluminal antireflux therapy.
beta-Aminoethyl Isothiourea
;
Esophagogastric Junction*
;
Follow-Up Studies
;
Fundoplication*
;
Gastroesophageal Reflux*
;
Humans
;
Logistic Models
;
Phenobarbital
;
Treatment Outcome
7.Protective effects of salubrinal on liver injury in rat models of brain death.
Tao WANG ; Shui-Jun ZHANG ; Sheng-Li CAO ; Wen-Zhi GUO ; Bing YAN ; Hong-Bo FANG
Chinese Medical Journal 2015;128(11):1523-1528
BACKGROUNDPrevious studies have indicated that endoplasmic reticulum stress participates in and mediates liver injury and apoptosis in brain-dead (BD) rats. In this study, we observed the effect of salubrinal (Sal, Sigma, USA) on liver cells in BD rats and explored its relevant mechanisms.
METHODSThirty Sprague-Dawley rats were equally randomized into three groups: BD group, Sal group, and DMSO group. The BD models were established by increasing intracranial pressure in a modified, slow, and intermittent way. In the drug groups, Sal was administered 1 h before the induction of BD. After modeling was completed, the blood and liver samples were harvested. CHOP and Caspase-12 mRNA expression was detected using quantitative polymerase chain reaction. PKR-like ER kinase (PERK), P-eukaryotic translation initiation factor 2α (eIF2α), eIF2α, CHOP and caspase-12 expression was detected using western blotting (WB). CHOP and caspase-12 distribution and expression in liver tissues were determined using immunohistochemistry (IHC). Alanine aminotransferase and aspartate aminotransferase level were detected using an automatic biochemical analyzer. Hepatic cell apoptosis was detected using TUNEL. The results were analyzed using Quantity-one v4.62 software (Bio-Rad, USA).
RESULTSCHOP and caspase-12 expression and PERK, eIF2α, and P-eIF2α protein expression showed no significant difference between BD group and DMSO group. Compared with BD group, Sal group had a significantly higher P-eIF2C level and a lower P-PERK level 2 h and 6 h after BD (P < 0.05). However, eIF2α expression showed no significant difference (P > 0.05). After the Sal treatment, CHOP and caspase-12 mRNA expression significantly decreased 4 h after BD (P < 0.05). WB and IHC indicated that CHOP and caspase-12 expression also significantly decreased after Sal treatment. Sal was associated with improved liver function and decreased hepatic cell apoptosis.
CONCLUSIONSSal can significantly reduce apoptosis in hepatic cells of BD rats. This protective effect may be achieved via the PERK-eIF2α signaling pathway.
Animals ; Apoptosis ; drug effects ; Blotting, Western ; Brain Death ; metabolism ; Caspase 12 ; genetics ; metabolism ; Cinnamates ; Disease Models, Animal ; Endoplasmic Reticulum Stress ; drug effects ; Eukaryotic Initiation Factor-2 ; genetics ; metabolism ; Immunohistochemistry ; Liver ; drug effects ; injuries ; Male ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Thiourea ; analogs & derivatives ; Transcription Factor CHOP ; genetics ; metabolism
8.SPA0355 attenuates ischemia/reperfusion-induced liver injury in mice.
Ui Jin BAE ; Jae Do YANG ; Sun O KA ; Jeung Hyun KOO ; Seong Ji WOO ; Young Rae LEE ; Hee Chul YU ; Baik Hwan CHO ; Hui Yuan ZHAO ; Jae Ha RYU ; Sang Myeong LEE ; Raok JEON ; Byung Hyun PARK
Experimental & Molecular Medicine 2014;46(8):e109-
Hepatic ischemia/reperfusion (I/R) injury leads to oxidative stress and acute inflammatory responses that cause liver damage and have a considerable impact on the postoperative outcome. Much research has been performed to develop possible protective techniques. We aimed to investigate the efficacy of SPA0355, a synthetic thiourea analog, in an animal model of hepatic I/R injury. Male C57BL/6 mice underwent normothermic partial liver ischemia for 45 min followed by varying periods of reperfusion. The animals were divided into three groups: sham operated, I/R and SPA0355 pretreated. Pretreatment with SPA0355 protected against hepatic I/R injury, as indicated by the decreased levels of serum aminotransferase and reduced parenchymal necrosis and apoptosis. Liver synthetic function was also restored by SPA0355 as reflected by the prolonged prothrombin time. To gain insight into the mechanism involved in this protection, we measured the activity of nuclear factor-kappaB (NF-kappaB), which revealed that SPA0355 suppressed the nuclear translocation and DNA binding of NF-kappaB subunits. Concomitantly, the expression of NF-kappaB target genes such as IL-1beta, IL-6, TNF-alpha and iNOS was significantly downregulated. Lastly, the liver antioxidant enzymes superoxide dismutase, catalase and glutathione were upregulated by SPA0355 treatment, which correlated with the reduction in serum malondialdehyde. Our results suggest that SPA0355 pretreatment prior to I/R injury could be an effective method to reduce liver damage.
Animals
;
Anti-Inflammatory Agents/*therapeutic use
;
Benzoxazines/*therapeutic use
;
Liver/*drug effects/immunology/*injuries/pathology
;
Male
;
Mice, Inbred C57BL
;
NF-kappa B/immunology
;
Reperfusion Injury/*drug therapy/immunology/pathology
;
Signal Transduction/drug effects
;
Thiourea/*analogs & derivatives/therapeutic use
9.The Modulatory Role of Spinally Located Histamine Receptors in the Regulation of the Blood Glucose Level in D-Glucose-Fed Mice.
Yun Beom SIM ; Soo Hyun PARK ; Sung Su KIM ; Chea Ha KIM ; Su Jin KIM ; Su Min LIM ; Jun Sub JUNG ; Ohk Hyun RYU ; Moon Gi CHOI ; Hong Won SUH
The Korean Journal of Physiology and Pharmacology 2014;18(1):41-46
The possible roles of spinal histamine receptors in the regulation of the blood glucose level were studied in ICR mice. Mice were intrathecally (i.t.) treated with histamine 1 (H1) receptor agonist (2-pyridylethylamine) or antagonist (cetirizine), histamine 2 (H2) receptor agonist (dimaprit) or antagonist (ranitidine), histamine 3 (H3) receptor agonist (alpha-methylhistamine) or antagonist (carcinine) and histamine 4 (H4) receptor agonist (VUF 8430) or antagonist (JNJ 7777120), and the blood glucose level was measured at 30, 60 and 120 min after i.t. administration. The i.t. injection with alpha-methylhistamine, but not carcinine slightly caused an elevation of the blood glucose level. In addition, histamine H1, H2, and H4 receptor agonists and antagonists did not affect the blood glucose level. In D-glucose-fed model, i.t. pretreatment with cetirizine enhanced the blood glucose level, whereas 2-pyridylethylamine did not affect. The i.t. pretreatment with dimaprit, but not ranitidine, enhanced the blood glucose level in D-glucose-fed model. In addition, alpha-methylhistamine, but not carcinine, slightly but significantly enhanced the blood glucose level D-glucose-fed model. Finally, i.t. pretreatment with JNJ 7777120, but not VUF 8430, slightly but significantly increased the blood glucose level. Although histamine receptors themselves located at the spinal cord do not exert any effect on the regulation of the blood glucose level, our results suggest that the activation of spinal histamine H2 receptors and the blockade of spinal histamine H1 or H3 receptors may play modulatory roles for up-regulation and down-regulation, respectively, of the blood glucose level in D-glucose fed model.
Animals
;
Blood Glucose*
;
Cetirizine
;
Dimaprit
;
Down-Regulation
;
Glucose
;
Histamine*
;
Mice*
;
Mice, Inbred ICR
;
Ranitidine
;
Receptors, Histamine H2
;
Receptors, Histamine H3
;
Receptors, Histamine*
;
Spinal Cord
;
Up-Regulation
10.The efficacy of SPA0355 in protecting beta cells in isolated pancreatic islets and in a murine experimental model of type 1 diabetes.
Ui Jin BAE ; Mi Young SONG ; Hyun Young JANG ; Hyo Jin GIM ; Jae Ha RYU ; Sang Myeong LEE ; Raok JEON ; Byung Hyun PARK
Experimental & Molecular Medicine 2013;45(11):e51-
Cytokines activate several inflammatory signals that mediate beta-cell destruction. We recently determined that SPA0355 is a strong anti-inflammatory compound, thus reporting its efficacy in protecting beta cells from various insults. The effects of SPA0355 on beta-cell survival were studied in RINm5F cells and primary islets. The protective effects of this compound on the development of type 1 diabetes were evaluated in non-obese diabetic (NOD) mice. SPA0355 completely prevented cytokine-induced nitric oxide synthase (iNOS) expression and cytotoxicity in RINm5F cells and isolated islets. The molecular mechanism of SPA0355 inhibition of iNOS expression involves the inhibition of nuclear factor kappaB and Janus kinase signal transducer and activator of transcription pathways. The protective effects of SPA0355 against cytokine toxicity were further demonstrated by normal insulin secretion and absence of apoptosis of cytokine-treated islets. In experiments with NOD mice, the occurrence of diabetes was efficiently reduced when the mice were treated with SPA0355. Therefore, SPA0355 might be a valuable treatment option that delays the destruction of pancreatic beta cells in type 1 diabetes.
Animals
;
Apoptosis
;
Benzoxazines/pharmacology/*therapeutic use
;
Cell Line
;
Cell Survival
;
Cells, Cultured
;
Diabetes Mellitus, Experimental/*prevention & control
;
Insulin-Secreting Cells/*drug effects/metabolism
;
Janus Kinases/genetics/metabolism
;
Mice
;
Mice, Inbred NOD
;
NF-kappa B/genetics/metabolism
;
Nitric Oxide Synthase Type II/genetics/metabolism
;
Rats
;
Thiourea/*analogs & derivatives/pharmacology/therapeutic use

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