1.Inhibitory Effects of ECQ on Indomethacin-Induced Gastric Damage in Rats.
Juho JUNG ; Yoonjin NAM ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2012;16(6):399-404
We investigated inhibitory effects of extract containing quercetin-3-O-beta-D-glucuronopyranoside (ECQ) extracted from Rumex Aquaticus Herba on indomethacin-induced gastric damage in Rats. Gastritis was induced in male Sprague-Dawley rats (200~220 g) by oral administration of indomethacin at a dose of 40 mg/kg. One hour before administration of indomethacin, animals were orally pretreated with ECQ at doses of 0.3, 1, 3 or 10 mg/kg. Six hours after indomethacin administration, the rats were sacrificed and the stomach was excised and opened along the greater curvature, and the surface area of gastric lesion was measured using optical microscope. Superoxide dismutase (SOD), catalase (CAT), myeloperoxidase (MPO) activities and malondialdehyde (MDA) levels were measured by ELISA. Western blot analysis was performed to detect protein expression of SOD-2. Linear hemorrhagic mucosal lesions were observed in the stomach 6 hours after oral administration of indomethacin. Pretreatment with ECQ significantly reduced the severity of the lesions in a dose-dependent manner. It also inhibited the reductions in SOD and CAT activities and SOD expression by the indomethacin-induced gastric damage. In addition, the pretreatment with ECQ significantly suppressed the elevation of the MPO activity and the MDA levels induced by indomethacin. These results suggest that ECQ has the inhibitory effects via antioxidative action against indomethacin-induced gastritis in rats.
Administration, Oral
;
Animals
;
Blotting, Western
;
Catalase
;
Cats
;
Enzyme-Linked Immunosorbent Assay
;
Gastritis
;
Humans
;
Indomethacin
;
Male
;
Malondialdehyde
;
Peroxidase
;
Quercetin
;
Rats
;
Rats, Sprague-Dawley
;
Rumex
;
Stomach
;
Superoxide Dismutase
2.Gastroprotective Effect of the Three Glucuronopyranoside Flavonoids in Rats.
Wi Joon IM ; Yoonjin NAM ; Sun Young PARK ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2013;17(5):411-415
In this study, we investigated the protective action of glucuronopyranoside flavonoids (QGC, AGC, LGC) on gastritis in rats. QGC, AGC and omeprazole decreased the gastric volume significantly, and each ID50 was 0.75, 0.54 and 8.5 mg/kg, respectively, thus the order of potency was AGC, QGC and omeprazole. They also decreased acid output, and each ID50 was 7.81, 0.58 and 6.71 mg/kg, respectively, thus the order of potency was AGC, omeprazole and QGC. They inhibited gastritis induced by indomethacin, and it recovered significantly by increasing the GSH levels in gastritis. The gastric MPO activity in the gastritis group increased more than in the normal group. QGC, LGC, or AGC administration reduced moderately the MPO activity in a dose-dependent manner. This study demonstrated that AGC, QGC, or LGC showed potent efficacy on the gastritis, by preventing oxidative stress. These results suggest that QGC, AGC, or LGC have gastroprotective effect in rats.
Animals
;
Flavonoids*
;
Gastritis
;
Indomethacin
;
Lipid Peroxidation
;
Omeprazole
;
Oxidative Stress
;
Rats*
3.The Protective Effect of Eupatilin against Hydrogen Peroxide-Induced Injury Involving 5-Lipoxygenase in Feline Esophageal Epithelial Cells.
Jae Chun LIM ; Sun Young PARK ; Yoonjin NAM ; Thanh Thao NGUYEN ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2012;16(5):313-320
In this study, we focused to identify whether eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone), an extract from Artemisia argyi folium, prevents H2O2-induced injury of cultured feline esophageal epithelial cells. Cell viability was measured by the conventional MTT reduction assay. Western blot analysis was performed to investigate the expression of 5-lipoxygenase by H2O2 treatment in the absence and presence of inhibitors. When cells were exposed to 600 microM H2O2 for 24 hours, cell viability was decreased to 40%. However, when cells were pretreated with 25~150 microM eupatilin for 12 hours, viability was significantly restored in a concentration-dependent manner. H2O2-treated cells were shown to express 5-lipoxygenase, whereas the cells pretreated with eupatilin exhibited reduction in the expression of 5-lipoxygenase. The H2O2-induced increase of 5-lipoxygenase expression was prevented by SB202190, SP600125, or NAC. We further demonstrated that the level of leukotriene B4 (LTB4) was also reduced by eupatilin, SB202190, SP600125, NAC, or nordihydroguaiaretic acid (a lipoxygenase inhibitor) pretreatment. H2O2 induced the activation of p38MAPK and JNK, this activation was inhibited by eupatilin. These results indicate that eupatilin may reduce H2O2-induced cytotoxicity, and 5-lipoxygenase expression and LTB4 production by controlling the p38 MAPK and JNK signaling pathways through antioxidative action in feline esophageal epithelial cells.
Anthracenes
;
Arachidonate 5-Lipoxygenase
;
Artemisia
;
Blotting, Western
;
Cell Survival
;
Epithelial Cells
;
Flavonoids
;
Hydrogen
;
Hydrogen Peroxide
;
Imidazoles
;
Leukotriene B4
;
Lipoxygenase
;
MAP Kinase Signaling System
;
Nordihydroguaiaretic Acid
;
p38 Mitogen-Activated Protein Kinases
;
Pyridines
4.The hepato-protective effect of eupatilin on an alcoholic liver disease model of rats
Hak Yeong LEE ; Yoonjin NAM ; Won Seok CHOI ; Tae Wook KIM ; Jaehwi LEE ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2020;24(5):385-394
Eupatilin is known to possess anti-apoptotic, anti-oxidative, and antiinflammatoryproperties. We report here that eupatilin has a protective effect onthe ethanol-induced injury in rats. Sprague–Dawley rats were divided into 6 groups:control, vehicle, silymarin, eupatilin 10 mg/kg, eupatilin 30 mg/kg, and eupatilin 100mg/kg. Plasma levels of aspartate aminotransferase (AST) and alanine aminotransferase(ALT) were analyzed to determine the extent of liver damage. Total cholesterol(TC) and triglycerides (TG) were analyzed to determine the level of liver steatosis.Malondialdehyde level, superoxide dismutase (SOD) activity, and glutathione (GSH)level were analyzed to determine the extent of oxidative stress. Tumor necrosis factor(TNF)- and interleukin (IL)-1 were quantified to verify the degree of inflammation.Based on our findings, chronic alcohol treatment significantly changed the serumindexes and liver indicators of the model rats, which were significantly improved byeupatilin treatment. Rats in the eupatilin-treatment group showed reduced levelsof AST, ALT, TG, TC, TNF-, and IL-1, increased SOD activity and GSH levels, and improvedoverall physiology compared to the alcoholic liver disease model rats. H&Estaining also verified the eupatilin-mediated improvement in liver injury. In conclusion,eupatilin inhibits alcohol-induced liver injury via its antioxidant and anti-inflammatoryeffects.
5.The hepato-protective effect of eupatilin on an alcoholic liver disease model of rats
Hak Yeong LEE ; Yoonjin NAM ; Won Seok CHOI ; Tae Wook KIM ; Jaehwi LEE ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2020;24(5):385-394
Eupatilin is known to possess anti-apoptotic, anti-oxidative, and antiinflammatoryproperties. We report here that eupatilin has a protective effect onthe ethanol-induced injury in rats. Sprague–Dawley rats were divided into 6 groups:control, vehicle, silymarin, eupatilin 10 mg/kg, eupatilin 30 mg/kg, and eupatilin 100mg/kg. Plasma levels of aspartate aminotransferase (AST) and alanine aminotransferase(ALT) were analyzed to determine the extent of liver damage. Total cholesterol(TC) and triglycerides (TG) were analyzed to determine the level of liver steatosis.Malondialdehyde level, superoxide dismutase (SOD) activity, and glutathione (GSH)level were analyzed to determine the extent of oxidative stress. Tumor necrosis factor(TNF)- and interleukin (IL)-1 were quantified to verify the degree of inflammation.Based on our findings, chronic alcohol treatment significantly changed the serumindexes and liver indicators of the model rats, which were significantly improved byeupatilin treatment. Rats in the eupatilin-treatment group showed reduced levelsof AST, ALT, TG, TC, TNF-, and IL-1, increased SOD activity and GSH levels, and improvedoverall physiology compared to the alcoholic liver disease model rats. H&Estaining also verified the eupatilin-mediated improvement in liver injury. In conclusion,eupatilin inhibits alcohol-induced liver injury via its antioxidant and anti-inflammatoryeffects.
6.Effects of Fixation and Storage of Human Tissue Samples on Nucleic Acid Preservation.
Soo Kyung NAM ; Joon IM ; Yoonjin KWAK ; Nayoung HAN ; Kyung Han NAM ; An Na SEO ; Hye Seung LEE
Korean Journal of Pathology 2014;48(1):36-42
BACKGROUND: Because of recent advances in the molecular diagnosis of cancer patients, tissue quality has become more important in daily practice. METHODS: To evaluate the effects of fixative, duration of fixation, decalcification, and storage periods on nucleic acid integrity, DNA and RNA were extracted from gastrointestinal cancer tissue. The yield and purity were analyzed, and polymerase chain reaction (PCR) for glyceraldehyde 3-phosphate dehydrogenase (GAPDH; 60 bp), beta-actin (148 bp), and human growth hormone (hGH; 434 bp) and real-time reverse transcription-PCR for beta-actin (97 bp) were performed. RESULTS: All formalin-fixed paraffin-embedded (FFPE) and methacarn-fixed paraffin-embedded (MFPE) samples tested positive for GAPDH and beta-actin by PCR. hGH was successfully detected in all MFPE samples, but in only 46.7% of the FFPE samples. Prolonged formalin fixation resulted in fewer GAPDH and beta-actin PCR products, and amplification of hGH was not successful. The PCR and reverse transcription-PCR results were significantly affected by the duration of decalcification. The yield, purity, and integrity of mRNA progressively decreased with increased storage periods of paraffin blocks. CONCLUSIONS: Fixation and storage should therefore be standardized in order to improve the quality of molecular pathologic diagnosis.
Actins
;
Diagnosis
;
DNA
;
Formaldehyde
;
Gastrointestinal Neoplasms
;
Glyceraldehyde 3-Phosphate
;
Human Growth Hormone
;
Humans*
;
Oxidoreductases
;
Paraffin
;
Polymerase Chain Reaction
;
RNA
;
RNA, Messenger
7.The Inhibitory Mechanism on Acetylcholine-Induced Contraction of Bladder Smooth Muscle in the Streptozotocin-Induced Diabetic Rat.
Jong Soo HAN ; Su Jin KIM ; Yoonjin NAM ; Hak Yeong LEE ; Geon Min KIM ; Dong Min KIM ; Uy Dong SOHN
Biomolecules & Therapeutics 2019;27(1):101-106
Most diabetic patients experience diabetic mellitus (DM) urinary bladder dysfunction. A number of studies evaluate bladder smooth muscle contraction in DM. In this study, we evaluated the change of bladder smooth muscle contraction between normal rats and DM rats. Furthermore, we used pharmacological inhibitors to determine the differences in the signaling pathways between normal and DM rats. Rats in the DM group received an intraperitoneal injection of 65 mg/kg streptozotocin and measured blood glucose level after 14 days to confirm DM. Bladder smooth muscle contraction was induced using acetylcholine (ACh, 10⁻⁴ M). The materials such as, atropine (a muscarinic receptor antagonist), U73122 (a phospholipase C inhibitor), DPCPX (an adenosine A1 receptor antagonist), udenafil (a PDE5 inhibitor), prazosin (an α₁-receptor antagonist), papaverine (a smooth muscle relaxant), verapamil (a calcium channel blocker), and chelerythrine (a protein kinase C inhibitor) were pre-treated in bladder smooth muscle. We found that the DM rats had lower bladder smooth muscle contractility than normal rats. When prazosin, udenafil, verapamil, and U73122 were pre-treated, there were significant differences between normal and DM rats. Taken together, it was concluded that the change of intracellular Ca²⁺ release mediated by PLC/IP3 and PDE5 activity were responsible for decreased bladder smooth muscle contractility in DM rats.
Acetylcholine
;
Animals
;
Atropine
;
Blood Glucose
;
Calcium Channels
;
Humans
;
Injections, Intraperitoneal
;
Muscle, Smooth*
;
Papaverine
;
Prazosin
;
Protein Kinase C
;
Rats*
;
Receptor, Adenosine A1
;
Receptors, Muscarinic
;
Streptozocin
;
Type C Phospholipases
;
Urinary Bladder*
;
Verapamil
8.Hepatoprotective effect of sodium hydrosulfide on hepatic encephalopathy in rats
Kyoung Wan KWON ; Yoonjin NAM ; Won Seok CHOI ; Tae Wook KIM ; Geon Min KIM ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2019;23(4):263-270
Hydrogen sulfide is well-known to exhibit anti-inflammatory and cytoprotective activities, and also has protective effects in the liver. This study aimed to examine the protective effect of hydrogen sulfide in rats with hepatic encephalopathy, which was induced by mild bile duct ligation. In this rat model, bile ducts were mildly ligated for 26 days. Rats were treated for the final 5 days with sodium hydrosulfide (NaHS). NaHS (25 µmol/kg), 0.5% sodium carboxymethyl cellulose, or silymarin (100 mg/kg) was administered intraperitoneally once per day for 5 consecutive days. Mild bile duct ligation caused hepatotoxicity and inflammation in rats. Intraperitoneal NaHS administration reduced levels of aspartate aminotransferase and alanine aminotransferase, which are indicators of liver disease, compared to levels in the control mild bile duct ligation group. Levels of ammonia, a major causative factor of hepatic encephalopathy, were also significantly decreased. Malondialdehyde, myeloperoxidase, catalase, and tumor necrosis factor-α levels were measured to confirm antioxidative and anti-inflammatory effects. N-Methyl-D-aspartic acid (NMDA) receptors with neurotoxic activity were assessed for subunit NMDA receptor subtype 2B. Based on these data, NaHS is suggested to exhibit hepatoprotective effects and guard against neurotoxicity through antioxidant and anti-inflammatory actions.
Alanine Transaminase
;
Ammonia
;
Animals
;
Aspartate Aminotransferases
;
Bile Ducts
;
Carboxymethylcellulose Sodium
;
Catalase
;
Hepatic Encephalopathy
;
Hydrogen Sulfide
;
Inflammation
;
Ligation
;
Liver
;
Liver Diseases
;
Malondialdehyde
;
Models, Animal
;
N-Methylaspartate
;
Necrosis
;
Peroxidase
;
Rats
;
Silymarin
;
Sodium
9.Ligand-Independent Epidermal Growth Factor Receptor Overexpression Correlates with Poor Prognosis in Colorectal Cancer.
Sumi YUN ; Yoonjin KWAK ; Soo Kyung NAM ; An Na SEO ; Heung Kwon OH ; Duck Woo KIM ; Sung Bum KANG ; Hye Seung LEE
Cancer Research and Treatment 2018;50(4):1351-1361
PURPOSE: Molecular treatments targeting epidermal growth factor receptors (EGFRs) are important strategies for advanced colorectal cancer (CRC). However, clinicopathologic implications of EGFRs and EGFR ligand signaling have not been fully evaluated. We evaluated the expression of EGFR ligands and correlation with their receptors, clinicopathologic factors, and patients’ survival with CRC. MATERIALS AND METHODS: The expression of EGFR ligands, including heparin binding epidermal growth factor-like growth factor (HBEGF), transforming growth factor (TGF), betacellulin, and epidermal growth factor (EGF), were evaluated in 331 consecutive CRC samples using mRNA in situ hybridization (ISH). We also evaluated the expression status of EGFR, human epidermal growth factor receptor 2 (HER2), HER3, and HER4 using immunohistochemistry and/or silver ISH. RESULTS: Unlike low incidences of TGF (38.1%), betacellulin (7.9%), and EGF (2.1%), HBEGF expression was noted in 62.2% of CRC samples. However, the expression of each EGFR ligand did not reveal significant correlations with survival. The combined analyses of EGFR ligands and EGFR expression indicated that the ligands–/EGFR+ group showed a significant association with the worst disease-free survival (DFS; p=0.018) and overall survival (OS; p=0.005). It was also an independent, unfavorable prognostic factor for DFS (p=0.026) and OS (p=0.007). Additionally, HER4 nuclear expression, regardless of ligand expression, was an independent, favorable prognostic factor for DFS (p=0.034) and OS (p=0.049), by multivariate analysis. CONCLUSION: Ligand-independent EGFR overexpression was suggested to have a significant prognostic impact; thus, the expression status of EGFR ligands, in addition to EGFR, might be necessary for predicting patients' outcome in CRC.
Betacellulin
;
Colorectal Neoplasms*
;
Disease-Free Survival
;
Epidermal Growth Factor*
;
Heparin
;
Humans
;
Immunohistochemistry
;
In Situ Hybridization
;
Incidence
;
Ligands
;
Multivariate Analysis
;
Prognosis*
;
Receptor, Epidermal Growth Factor*
;
RNA, Messenger
;
Silver
;
Transforming Growth Factors
10.The change of signaling pathway on the electrical stimulated contraction in streptozotocin-induced bladder dysfunction of rats.
Jong Soo HAN ; Young Sil MIN ; Gil Hyung KIM ; Sang hyun CHAE ; Yoonjin NAM ; Jaehwi LEE ; Seok Yong LEE ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2018;22(5):577-584
Bladder dysfunction is a common complication of diabetes mellitus (DM). However, there have been a few studies evaluating bladder smooth muscle contraction in DM in the presence of pharmacological inhibitors. In the present study, we compared the contractility of bladder smooth muscle from normal rats and DM rats. Furthermore, we utilized pharmacological inhibitors to delineate the mechanisms underlying bladder muscle differences between normal and DM rats. DM was established in 14 days after using a single injection of streptozotocin (65 mg/kg, intraperitoneal) in Sprague-Dawley rats. Bladder smooth muscle contraction was induced electrically using electrical field stimulation consisting of pulse trains at an amplitude of 40 V and pulse duration of 1 ms at frequencies of 2–10 Hz. In this study, the pharmacological inhibitors atropine (muscarinic receptor antagonist), U73122 (phospholipase C inhibitor), DPCPX (adenosine A₁ receptor antagonist), udenafil (PDE5 inhibitor), prazosin (α₁-receptor antagonist), verapamil (calcium channel blocker), and chelerythrine (protein kinase C inhibitor) were used to pretreat bladder smooth muscles. It was found that the contractility of bladder smooth muscles from DM rats was lower than that of normal rats. In addition, there were significant differences in percent change of contractility between normal and DM rats following pretreatment with prazosin, udenafil, verapamil, and U73122. In conclusion, we suggest that the decreased bladder muscle contractility in DM rats was a result of perturbations in PLC/IP₃-mediated intracellular Ca²⁺ release and PDE5 activity.
Animals
;
Atropine
;
Diabetes Mellitus
;
Muscle, Smooth
;
Phosphotransferases
;
Prazosin
;
Rats*
;
Rats, Sprague-Dawley
;
Streptozocin
;
Type C Phospholipases
;
Urinary Bladder*
;
Verapamil