Publications by authors named "Sang-Soo Sim"

Our study aimed to investigate the effects of the polysaccharide-rich extract of (PEP) against water immersion restraint (WIR) stress and forced swimming-induced fatigue. Exposure to WIR stress significantly increased the ulcer index, bleeding score, the weight of the adrenal gland, blood glucose concentrations, total cholesterol, cortisol, and creatine kinase (CK). The weight of the spleen decreased significantly.

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HM41322 is a novel oral sodium-glucose cotransporter (SGLT) 1/2 dual inhibitor. In this study, the and pharmacokinetic and pharmacologic profiles of HM41322 were compared to those of dapagliflozin. HM41322 showed a 10-fold selectivity for SGLT2 over SGLT1.

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To investigate the inhibitory effect of acteoside on the process of exocytosis induced by melittin, we measured Ca(2+) mobilization, arachidonic acid (AA) release and catecholamine exocytosis in PC12 chromaffin cells. Melittin significantly increased the intracellular Ca(2+) mobilization via receptor-operated calcium channel but not the intracellular Ca(2+) release. It caused AA release via activation of Ca(2+)-dependent phospholipase A2 (PLA2) and catecholamine secretion in a dose-dependent manner.

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To investigate the underlying mechanisms of C18 fatty acids (stearic acid, oleic acid, linoleic acid and α-linolenic acid) on mast cells, we measured the effect of C18 fatty acids on intracellular Ca(2+) mobilization and histamine release in RBL-2H3 mast cells. Stearic acid rapidly increased initial peak of intracellular Ca(2+) mobilization, whereas linoleic acid and α-linolenic acid gradually increased this mobilization. In the absence of extracellular Ca(2+), stearic acid (100 µM) did not cause any increase of intracellular Ca(2+) mobilization.

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We investigated the antihypertensive effect of lutein on N(G) -nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertensive rats. Daily oral administration of L-NAME (40 mg/kg)-induced a rapid progressive increase in mean arterial pressure (MAP). L-NAME significantly increased MAP from the first week compared to that in the control and reached 193.

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This study was performed to investigate the effects of acteoside on various cellular functions such as, intracellular Ca(2+) mobilization, phospholipase C activity, and exocytosis induced by melittin. Melittin (0.1-1 μM) dose-dependently increased intracellular Ca(2+) mobilization in the presence of extracellular Ca(2+), but was not affected by 1 μM U73122, a specific PLC inhibitor.

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The aim of this study was to investigate whether acteoside isolated from Clerodendron trichotomum Thunberg may act as a selective inhibitor of phospholipase A(2) in RBL-2H3 cells. Acteoside dose-dependently inhibited 0.5 μM melittin-induced release of [(3)H]arachidonic acid, which was due to the inhibition of cytosolic Ca(2+)-dependent phospholipase A(2) (cPLA(2)) rather than secretory PLA(2) (sPLA(2)).

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The effects of extremely low frequency electromagnetic fields (EMF) on intracellular Ca(2+) mobilization and cellular function in RBL 2H3 cells were investigated. Exposure to EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h did not produce any cytotoxic effects in RBL 2H3 cells.

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The mechanism of the protective effect of quercetin-3-O-β-D-glucuronopyranoside (QGC) from the leaves of Rumex aqauticus on indomethacin (IND, a representative NSAID)-induced gastric damage in rats was investigated. Pre-treatment with QGC significantly attenuated IND-induced gastric mucosal injury. An increase in myeloperoxidase (MPO) activity and expression of intercellular adhesion molecule (ICAM)-1 protein and mRNA expression of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β, as well as a decrease in gastric mucus secretion were detected in the gastric mucosa of IND-treated rats.

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This study was conducted to investigate the effects of extremely low frequency electromagnetic fields (EMF) on signal pathway in plasma membrane of cultured cells (RAW 264.7 cells and RBL 2H3 cells), by measuring the activity of phospholipase A(2) (PLA(2)), phospholipase C (PLC) and phospholipase D (PLD). The cells were exposed to the EMF (60 Hz, 0.

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Objectives: We have investigated the effect of lutein on phospholipase A₂ (PLA₂) isozymes.

Methods: We measured arachidonic acid release in [³H]arachidonic acid-labelled Raw 264.7 cells and PLA₂ activity using 1-palmitoyl-2-[¹⁴C]arachidonyl phosphatidylcholine ([¹⁴C]AA-PC) and 10-pyrene phosphatidylcholine in vitro.

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Previously, we reported that dibenzylbutyrolactone lignans (DBLLs) from the fruit of Forsythia koreana NAKAI (Oleaceae) has anti-inflammatory, antioxidant, and anti-asthmatic effects. In this study, to clarify the anti-inflammatory mechanisms of DBLL, we evaluated the effects of DBLLs on lipopolysaccharide-stimulated inducible nitric oxide synthetase (iNOS) and cyclooxygenase-2 (COX-2) expressions, nitric oxide (NO) and prostaglandin E(2) (PGE(2)) productions, nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) activations, inhibitor of κB (IκB) and inhibitor of κB kinase (IKK) phosphorylations in cytosolic proteins, and cytotoxicity in Raw264.7 cells.

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Clerodendron trichotomum leaves and Rumex aquatica herbs are used as a folk medicine for the treatment of inflammatory diseases, but their active ingredients are not known until now. We isolated caffeic acid and phenylpropanoid glycosides, 1-O-caffeoyl glycoside and acteoside [β-(3',4'-dihydroxyphenyl) ethyl-O-α-l-rhamnopyranosyl(1→3)-β-d-(4-O-caffeoyl)-glucopyranoside] from their ethylacetate fractions, respectively, and evaluated their anti-asthmatic effects on the aerosolized ovalbumin (OA) challenge in the OA-sensitized guinea-pigs measuring the specific airway resistance (sRaw) during the immediate-phase response (IAR) and late-phase response (LAR), and also measured recruitment of leukocytes and chemical mediators on the bronchoalveolar lavage fluids (BALF) in LAR, as well as histopathological survey. Acteoside and 1-O-caffeoyl glycoside (25mg/kg) significantly (P<0.

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This study investigated the effects of the methanol extracts of Morinda citrifolia containing numerous anthraquinone and iridoid on phospholipase A(2) (PLA(2)) isozyme. PLA(2) activity was measured using various PLA(2) substrates, including 10-pyrene phosphatidylcholine, 1-palmitoyl-2-[(14)C]arachidonyl phosphatidylcholine ([(14)C]AA-PC), and [(3)H]arachidonic acid (AA). The methanol extracts suppressed melittin-induced [(3)H]AA release in a concentration-dependent manner in RAW 264.

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We studied effects of hydrolysable tannins on rat papillary muscle contractions induced by propranolol. The developed force of papillary muscle was measured isometrically with an inductive force transducer. The IC(50) values for digallic acid, gallic acid, germin D, praecoxin A and 1-desgalloyl rugosin F were 4.

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We previously reported that quercetin and rutin have potent, anti-asthmatic activity, but the structure-activity relationships of flavonoids and anti-asthmatic agents are still poorly understood. In the current study, the effects of kaempferol, fisetin, and morin on the immediate-phase response (IAR) and late-phase response (LAR) caused by exposure to aerosolized-ovalbumin (OA) in OA-sensitized guinea pigs were evaluated by determining the specific airway resistance (sRaw), recruitment of leukocytes and chemical mediators in bronchoalveolar lavage fluid (BALF), histopathological surveys, and determination of neutrophil chemotaxis. Fisetin and kaempherol (30 mg/kg, p.

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We have shown that myosin light chain kinase (MLCK) was required for the off-contraction in response to the electrical field stimulation (EFS) of feline esophageal smooth muscle. In this study, we investigated whether protein kinase C (PKC) may require the on-contraction in response to EFS using feline esophageal smooth muscle. The contractions were recorded using an isometric force transducer.

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This study evaluated the anti-asthmatic activities of four diterpene acids isolated from Aralia cordata root that are proposed to be the active ingredients in its traditional use as a treatment for inflammation, overheating, pain and spasm in Korea. The diterpene acids were identified as kaurenoic acid, 7-oxo-sandaracopimaric acid, 17-hydroxy-ent-kaur-15-en-19-oic acid, and hederagenin, by comparing their phytochemical and spectroscopic data with previous reports. The effects of diterpene acids on asthma were evaluated by determining the specific airway resistance (sRaw) during the immediate asthmatic response (IAR) and the late-phase asthmatic response (LAR) in guinea pigs with IgE-mediated asthma.

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This study was carried out to investigate the wound healing effect of caffeic acid in skin-incised mice. Caffeic acid showed significant effects on anti-inflammatory activity and wound healing, such as myeloperoxidase activity, lipid peroxidation, phospholipase A(2) activity and collagen-like polymer synthesis, in incised-wound tissue. On the other hand, it significantly stimulated collagen-like polymer synthesis in NIH 3T3 fibroblast cells, while inhibited both silica-induced reactive oxygen species generation and melittin-induced arachidonic acid release and PGE(2) production in Raw 264.

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The antioxidant effect of CoQ(10) on N-nitrosodiethylamine (NDEA)-induced oxidative stress was investigated in mice. Food intake and body weight were similar in both CoQ(10) and control groups during the 3-week experimental period. NDEA significantly increased the activities of typical marker enzymes of liver function (AST, ALT and ALP) both in control and CoQ(10) groups.

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It was evaluated the inhibitory action of quercetin-3-O-beta-D-glucuronopyranoside (QGC) on reflux esophagitis and gastritis in rats. QGC was isolated from the herba of Rumex Aquaticus. Reflux esophagitis or gastritis was induced surgically or by administering indomethacin, respectively.

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Objectives: The aim of the study was to determine the mechanism of the whitening effect of acteoside.

Methods: We used tyrosinase activity and melanin production stimulated in B16 melanoma cells by alpha-melanocyte stimulating hormone (alpha-MSH) or forskolin to measure the whitening effect of acteoside.

Key Findings: Acteoside did not directly inhibit mushroom tyrosinase activity, but dose-dependently inhibited tyrosinase activity and melanin production in B16 melanoma cells stimulated by 1 micromol/l alpha-MSH.

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Aim Of The Study: Water extract of Geijigajakyak-Tang (GJT) consisting of five crude drugs [dried root of P. lactiflora Peony (Paeoniaceae), dried trunk bark of C. cassia Blume (Lauraceae), seed of Z.

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Coenzyme Q10 (CoQ10) is a biosynthesized quinone with 10 isoprene side chains in humans. To investigate the anti-inflammatory and wound healing effect of CoQ10, we performed in vivo and in vitro experiments. In vivo studies, there were 3 groups; Naive (without skin incision), Control (with skin incision) and CoQ10 (100 mg/kg treatment with skin incision).

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Sphingosine 1-phosphate (S1P) is a bioactive lipid, stored and released from activated platelets, macrophages, and other mammalian cells. We previously reported that S1P induces esophageal smooth muscle contraction in freshly isolated intact cells. Here, we measured S1P-induced ERK1/2 activation and upstream signaling in cultured feline esophageal smooth muscle cells.

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