Ehn-Kyoung Choi

Chungbuk National University, Chinsen, North Chungcheong, South Korea

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Publications (22)18.51 Total impact

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    ABSTRACT: Helicobacter pylori-eliminating effects of FEMY-R7, composed of fucoidan and evening primrose extract, were investigated in mice and humans. Male C57BL/6 mice were infected with the bacteria by intragastric inoculation (1×10(9) CFU/mouse) 3 times at 2-day intervals, and simultaneously, orally treated twice a day with 10 or 100 mg/kg FEMY-R7 for 2 weeks. In Campylobcter-like organism-detection test, FEMY-R7 markedly reduced the urease-positive reactivity. In a clinical sudy, human subjects, confirmed to be infected with Helicobacter pylori, were orally administered twice a day with a capsule containing 150 mg FEMY-R7 for 8 weeks. FEMY-R7 significantly decreased both the Delta over baseline-value in urea breath test and the serum pepsinogens I and II levels. The results indicate that FEMY-R7 not only eliminates H. pylori from gastric mucosa of animals and humans, but also improves gastric function.
    Laboratory animal research. 09/2014; 30(3):131-5.
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    ABSTRACT: The effects of an ethanolic extract of Angelica gigas (EAG) on the vascular smooth muscle cell (VSMC) proliferation and high-cholesterol diet-induced hypercholesterolemia and atherosclerosis were investigated. Rat aortic VSMCs were stimulated with platelet-derived growth factor-BB (25 ng/mL) for the induction of DNA synthesis and cell proliferation. EAG (1-10 µg/mL) significantly inhibited both the thymidine incorporation and cell proliferation in a concentration-dependent manner. Hypercholesterolemia was induced by feeding male New Zealand white rabbits with 0.5% cholesterol in diet for 10 weeks, during which EAG (1% in diet) was given for the final 8 weeks after 2-week induction of hypercholesterolemia. Hypercholesterolemic rabbits exhibited great increases in serum total cholesterol and low-density lipoproteins (LDL) levels, and finally severe atheromatous plaque formation covering 28.4% of the arterial walls. EAG significantly increased high-density lipoproteins (HDL), slightly decreased LDL, and potentially reduced the atheroma area to 16.6%. The results indicate that EAG attenuates atherosclerosis not only by inhibiting VASC proliferation, but also by increasing blood HDL levels. Therefore, it is suggested that EAG could be an alternative or an adjunct therapy for the improvement of hypercholesterolemia and atherosclerosis.
    Laboratory animal research. 06/2014; 30(2):84-9.
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    ABSTRACT: Objectives Since oils and fats can induce metabolic syndrome, leading to cardiovascular and cerebrovascular diseases, the present study was performed to find out whether the plant oils affect the cerebral hemorrhage in stroke-prone spontaneously hypertensive (SHR-SP) rats. Methods From 47 days of age, male SHR-SP rats were given drinking water containing 1% NaCl to induce hypertension, and simultaneously fed semi-purified diets containing 10% perilla oil, canola oil, or shortening. The onset time of convulsion following cerebral hemorrhage was recorded, and the areas of hemorrhage and infarction were analyzed in the stroke brains. Results In comparison with 58-day survival of SHR-SP rats during feeding NaCl alone, perilla oil extended the survival time to 68.5 days, whereas canola oil shortened it to 45.7 days. Feeding perilla oil greatly reduced the total volume of cerebral hemorrhage from 17.27% in the control group to 4.53%, while shortening increased the lesions to 21.23%. In a microscopic analysis, perilla oil also markedly decreased the hemorrhagic and infarction lesions to 1/10 of those in control rats, in contrast to an exacerbating effect of shortening. In blood analyses, perilla oil reduced blood total cholesterol and low-density lipoproteins which were increased in SHR-SP, but canola oil further increased them and markedly lowered platelet counts. Discussion Perilla oil delayed and attenuated cerebral hemorrhage by improving hyperlipidemia in hypertensive stroke animals, in contrast to the aggravating potential of canola oil and shortening. It is suggested that perilla oil should be the first choice oil for improving metabolic syndrome in hypertensive persons at risk of hemorrhagic stroke.
    Nutritional Neuroscience 05/2014; · 1.65 Impact Factor
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    ABSTRACT: Effects of FEMY-R7, composed of fucoidan and evening primrose extract, on the bacterial growth and intragastric infection of Helicobacter pylori as well as gastric secretion were investigated in comparison with a proton-pump inhibitor pantoprazole. For in vitro anti-bacterial activity test, H. pylori (1×10(8) CFU/mL) was incubated with a serially-diluted FEMY-R7 for 3 days. As a result, FEMY-R7 fully inhibited the bacterial growth at 100 µg/mL, which was determined to be a minimal inhibitory concentration. In addition, 6-hour incubation with H. pylori, FEMY-R7 inhibited urease activity in a concentration-dependent manner, showing a median inhibitory concentration of 1,500 µg/mL. In vivo elimination study, male C57BL/6 mice were infected with the bacteria by intragastric inoculation (5×10(9) CFU/mouse) 3 times at 2-day intervals, and simultaneously, orally treated twice a day with 10, 30 or 100 mg/kg FEMY-R7 for 7 days. In Campylobcter-like organism-detection test and bacterial identification, FEMY-R7 exerted a high bacteria-eliminating capacity at 30-100 mg/kg, comparably to 30 mg/kg pantoprazole. In contrast to a strong antacid activity of pantoprazole in a pylorus-ligation study, FEMY-R7 did not significantly affect gastric pH, free HCl, and total acidity, although it significantly decreased fluid volume at a low dose (10 mg/kg). The results indicate that FEMY-R7 eliminate H. pylori from gastric mucosa by directly killing the bacteria and preventing their adhesion and invasion, rather than by inhibiting gastric secretion or mucosal damage.
    Laboratory animal research. 03/2014; 30(1):28-34.
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    ABSTRACT: The inhibitory effects of perilla oil on the platelet aggregation in vitro and thrombosis in vivo were investigated in comparison with aspirin, a well-known blood flow enhancer. Rabbit platelet-rich plasma was incubated with perilla oil and aggregation inducers collagen or thrombin, and the platelet aggregation rate was analyzed. Perilla oil significantly inhibited both the collagen- and thrombin-induced platelet aggregations, in which the thromboxane B2 formation from collagen-activated platelets were reduced in a concentration-dependent manner. Rats were administered once daily by gavage with perilla oil for 1 week, carotid arterial thrombosis was induced by applying 35% FeCl3-soaked filter paper for 10 min, and the blood flow was monitored with a laser Doppler probe. Perilla oil delayed the FeCl3-induced arterial occlusion in a dose-dependent manner, doubling the occlusion time at 0.5 mL/kg. In addition, a high dose (2 mL/kg) of perilla oil greatly prevented the occlusion, comparable to the effect of aspirin (30 mg/kg). The results indicate that perilla oil inhibit platelet aggregation by blocking thromboxane formation, and thereby delay thrombosis following oxidative arterial wall injury. Therefore, it is proposed that perilla oil could be a good candidate without adverse effects for the improvement of blood flow.
    Laboratory animal research. 03/2014; 30(1):21-7.
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    ABSTRACT: The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-dependent manner. Rats were orally administered with nattokinase for 1 week, and their carotid arteries were exposed. Arterial thrombosis was induced by applying 35% FeCl3-soaked filter paper for 10 min, and the blood flow was monitored with a laser Doppler probe. Nattokinase delayed the FeCl3-induced arterial occlusion in a dose-dependent manner, doubling the occlusion time at 160 mg/kg. In addition, a high dose (500 mg/kg) of nattokinase fully prevented the occlusion, as achieved with aspirin (30 mg/kg). The results indicate that nattokinase extracted from fermented soybean inhibit platelet aggregation by blocking thromboxane formation, and thereby delay thrombosis following oxidative arterial wall injury. Therefore, it is suggested that nattokinase could be a good candidate without adverse effects for the improvement of blood flow.
    Laboratory animal research. 12/2013; 29(4):221-5.
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    ABSTRACT: The neuroprotective effects of a butanol fraction of white rose petal extract (WRPE-BF) were investigated in a middle cerebral artery occlusion (MCAO) model. Seven week-old male rats were orally administered WRPE-BF for 2 weeks and subjected to MCAO for 2 h, followed by reperfusion. Twenty-four h later, MCAO-induced behavioral dysfunctions were markedly improved in a dose-dependent manner by pretreatment with WRPE-BF. Moreover, higher dose of WRPE-BF not only decreased infarction area but also effectively reduced astrogliosis. The expression of inducible nitric oxide synthase, cyclooxygenase-2, and glial fibrillary acidic protein in MCAO model were markedly inhibited by WRPE-BF treatment. Notably, WRPE-BF decreased nitric oxide and malondialdehyde levels in the striatum and subventricular zone of stroke-challenged brains. These data suggested that WRPE-BF may exert its neuroprotective effects via anti-oxidative and anti-inflammatory activities against ischemia-reperfusion brain injury and could be a good candidate as a therapeutic target for ischemic stroke.
    Biomolecules and Therapeutics 11/2013; 21(6):454-461. · 0.79 Impact Factor
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    ABSTRACT: Aging is characterized by progressive loss of cognitive and memory functions as well as decrease in physical activities. In the present study, a human neural stem cell line (F3 NSC) over-expressing choline acetyltransferase (F3.ChAT), an enzyme responsible for acetylcholine synthesis, was generated and transplanted in the brain of 18-month-old male ICR mice. Four weeks post-transplantation, neurobehavioral functions, expression of ChAT enzyme, production of acetylcholine and neurotrophic factors, and expression of cholinergic nervous system markers in transplanted animals were investigated. F3.ChAT NSCs markedly improved both the cognitive function and physical activity of aging animals, in parallel with the elevation of brain acetylcholine level. Transplanted F3 and F3.ChAT cells were found to differentiate into neurons and astrocytes, and to produce ChAT proteins. Transplantation of the stem cells increased brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), enhanced expression of Trk B, and restored host microtubule-associated protein 2 and cholinergic nervous system. The results demonstrate that human NSCs over-expressing ChAT improve cognitive function and physical activity of aging mice, not only by producing ACh directly but also by restoring cholinergic neuronal integrity, which might be mediated by neurotrophins BDNF and NGF.
    Neurobiology of aging 05/2013; · 5.94 Impact Factor
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    ABSTRACT: According to a high anti-osteoporotic efficacy of Sigma Anti-bonding Molecule Calcium Carbonate (SAC), repeated-dose toxicities of SAC were investigated to assess its feasibility as drug or functional food ingredient. Male ICR mice were given drinking water containing 0.006, 0.02 or 0.06% SAC for 4 weeks. SAC feeding decreased the body weights and feed and water consumptions of mice in a dose-dependent manner, especially, leading to severe emaciation and 70% death in 3 weeks in the high-dose (0.06%) group. Not only kidney and heart weights, but also the levels of blood urea nitrogen, creatinine, aspartate transaminase, and creatine phospokinase significantly increased after SAC administration, indicative of nephrotoxicity and cardiotoxicity. Such renal and cardiac toxicities were also confirmed by microscopic findings, exhibiting renal crystals and cardiac fibrosis, which may be due to the insoluble crystal formation and calcium overload, respectively. In conclusion, it is suggested that no observed adverse effect level of SAC is lower than 0.006% in mice, and that a long-term intake may cause serious adverse effects on renal and cardiac functions.
    Laboratory animal research. 03/2013; 29(1):7-11.
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    ABSTRACT: Brain ageing leads to atrophy and degeneration of the cholinergic nervous system, resulting in profound neurobehavioral and cognitive dysfunction from decreased acetylcholine biosynthesis and reduced secretion of growth and neurotrophic factors. Human adipose tissue-derived mesenchymal stem cells (ADMSCs) were intravenously (1 × 10(6) cells) or intracerebroventricularly (4 × 10(5) cells) transplanted into the brains of 18-month-old mice once or four times at 2-week intervals. Transplantation of ADMSCs improved both locomotor activity and cognitive function in the aged animals, in parallel with recovery of acetylcholine levels in brain tissues. Transplanted cells differentiated into neurons and, in part, into astrocytes and produced choline acetyltransferase proteins. Transplantation of ADMSCs restored microtubule-associated protein 2 in brain tissue and enhanced Trk B expression and the concentrations of brain-derived neurotrophic factor and nerve growth factor. These results indicate that human ADMSCs differentiate into neural cells in the brain microenvironment and can restore physical and cognitive functions of aged mice not only by increasing acetylcholine synthesis but also by restoring neuronal integrity that may be mediated by growth/neurotrophic factors. © 2013 Wiley Periodicals, Inc.
    Journal of Neuroscience Research 02/2013; · 2.97 Impact Factor
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    ABSTRACT: The anti-obesity activities of Rapha diet® preparation containing silkworm pupa peptide, Garcinia cambogia, white bean extract, mango extract, raspberry extract, cocoa extract, and green tea extract were investigated in mice with dietary obesity. Male C57BL/6 mice were fed a high-fat diet (HFD) containing 3% Rapha diet® preparation for 8 weeks, and blood and tissue parameters of obesity were analyzed. The HFD markedly enhanced body weight gain by increasing the weights of epididymal, perirenal, and mesenteric adipose tissues. The increased body weight gain induced by HFD was significantly reduced by feeding Rapha diet® preparation, in which decreases in the weight of abdominal adipose tissue and the size of abdominal adipocytes were confirmed by microscopic examination. Long-term feeding of HFD increased blood triglycerides and cholesterol levels, leading to hepatic lipid accumulation. However, Rapha diet® preparation not only reversed the blood lipid levels, but also attenuated hepatic steatosis. The results indicate that Rapha diet® preparation could improve HFD-induced obesity by reducing both lipid accumulation and the size of adipocytes.
    Laboratory animal research. 12/2012; 28(4):265-71.
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    ABSTRACT: The anti-inflammatory effects of fuciodan and Cistanche tubulosa (CT) extract were investigated in vitro macrophage culture system and in vivo carrageenan-induced air pouch inflammation model. CT extract inhibited nitric oxide production from activated RAW 264.7 macrophage cells, while fucoidan was inactive. In vivo air pouch inflammation model, carrageenan-induced vascular exudation and increased nitric oxide and prostaglandin E(2) concentrations in the exudates were synergistically suppressed by co-administration of fucoidan or CT extract. Moreover, tissue inflammation was substantially attenuated by the combinational therapy. However, there was no synergistic effect against the inflammatory cell infiltration, although fucoidan and CT extract each markedly reduced the cell numbers. Therefore, it is suggested that fucoidan blocks infiltration of inflammatory cells, while CT extract inhibits activation of the cells, and that their combinational treatment could be a promising candidate for the relief of various types of inflammation.
    Laboratory animal research. 06/2012; 28(2):91-7.
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    ABSTRACT: Anti-inflammatory effects of Houttuynia cordata supercritical extract (HSE) were investigated in rat carrageenan-air pouch model. Oral administration of HSE (50-200 mg/kg) suppressed carrageenan-induced exudation and albumin leakage, as well as inflammatory cell infiltration at a high dose (200 mg/kg). Intraperitoneal injection of dexamethasone (2 mg/kg) only decreased exudation and cell infiltration, while indomethacin (2 mg/kg, i.p.) reduced exudate volume and albumin content without influence on the cell number. HSE lowered tumor-necrosis factor-α (TNF-α) and nitric oxide (NO), as well as prostaglandin E(2) (PGE(2)). Dexamethasone only reduced TNF-α and NO, while indomethacin decreased PGE(2). The results indicate that HSE exhibits anti-inflammatory effects by inhibiting both TNF-α-NO and cyclooxygenase-2-PGE(2) pathways.
    Laboratory animal research. 06/2012; 28(2):137-40.
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    ABSTRACT: The effects of polarized-light therapy (PLT) on high-cholesterol diet (HCD)-induced hypercholesterolemia and atherosclerosis were investigated in comparison with that of lovastatin in rabbits. Hypercholesterolemia was induced by feeding male New Zealand white rabbits with 1% cholesterol in diet for 2 weeks and maintained with 0.5% cholesterol for 6 weeks, followed by normal diet for 2 weeks for recovery. Lovastatin (0.002% in diet) or daily 5-min or 20-min PLT on the outside surface of ears was started 2 weeks after induction of hypercholesterolemia. Hypercholesterolemic rabbits exhibited great increases in serum cholesterol and low-density lipoproteins (LDL) levels, and finally severe atheromatous plaques formation covering 57.5% of the arterial walls. Lovastatin markedly reduced both the cholesterol and LDL, but the reducing effect (47.5%) on atheroma formation was relatively low. By comparison, 5-min PLT preferentially decreased LDL, rather than cholesterol, and thereby potentially reduced the atheroma area to 42.2%. Notably, 20-min PLT was superior to lovastatin in reducing both the cholesterol and LDL levels as well as the atheromatous plaque formation (26.4%). In contrast to the increases in blood alanine transaminase and aspartate transaminase following lovastatin treatment, PLT did not cause hepatotoxicity. In addition, PLT decreased platelets and hematocrit level. The results indicate that PLT attenuates atherosclerosis not only by lowering blood cholesterol and LDL levels, but also by improving blood flow without adverse effects. Therefore, it is suggested that PLT could be a safe alternative therapy for the improvement of hypercholesterolemia and atherosclerosis.
    Laboratory animal research. 03/2012; 28(1):39-46.
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    ABSTRACT: Effects of egg york containing IgY specific for Helicobacter pylori on the bacterial growth and intragastric infection were investigated in comparison with a proton-pump inhibitor pantoprazole. For in vitro anti-bacterial activity test, H. pylori (1×10(8) CFU/mL) was incubated with a serially diluted IgY for 3 days. As a result, IgY fully inhibited the bacterial growth at 16 mg/mL, which was determined to a minimal inhibitory concentration. In vivo elimination study, male C57BL/6 mice were infected with the bacteria by intragastric inoculation (1×10(8) CFU/mouse) 3 times at 2-day intervals, and 2 weeks later, orally treated twice a day with 50, 100, 200 or 500 mg/kg IgY for 18 days. After the final administration, biopsy sample of the gastric mucosa was assayed for the bacterial identification via urease, oxidase, catalase, nitrate reduction and H(2)S tests in addition to microscopic examination for mucosal inflammation. In CLO kit test, 75, 50, 12.5 and 12.5% of the animals revealed positive reaction following treatment with 50, 100, 200 and 500 mg/kg IgY, respectively, resulting in a superior efficacy at 200 mg/kg than 30 mg/kg pantoprazole that displayed 75% elimination. The CLO test results were confirmed by bacterial identification. Microscopic examination revealed that H. pylori infection caused severe gastric mucosal inflammation, which were not observed in the CLO-negative mice following treatment with IgY or pantoprazole. Taken together, IgY inhibited the growth of H. pylori, and improved gastritis and villi injuries by eliminating the bacteria from the stomach. The results indicate that IgY could be a good candidate overcoming tolerance of antibiotics for the treatment of H. pylori-mediated gastric ulcers.
    Laboratory animal research. 03/2012; 28(1):55-60.
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    ABSTRACT: The study investigated the correlation between infarction areas and behavioural deficits in middle cerebral artery occlusion (MCAO) and photothrombosis stroke models. In the MCAO model, a 0.38 mm-diameter silicone-coated thread was introduced through the left external carotid artery and advanced 18 mm via the internal carotid artery to the origin of middle cerebral artery of male Sprague-Dawley rats weighing 300-350 g. The thread was removed for reperfusion after occlusion for 0.5, 1 or 2h. In the photothrombosis model, after a midline incision on the scalp, a focused light (10,000 lux, 6 mm-diameter) was delivered 1mm anterior to the bregma and 3mm left of the midline for 5, 10 or 20 min. During the first 2 min of irradiation, Rose Bengal dye (30 mg/kg) was injected intravenously. Twenty four hours post-surgery, the animals were subjected to neurological scoring and behavioural performances, and were sacrificed for macroscopic and microscopic examinations of brain injury. Total infarction volumes in the MCAO model rats increased in an occlusion time-dependent manner, while the infarction volumes in photothrombosis model rats plateaued relatively quickly with no time-dependent increase. The MCAO model displayed neurological scores and behavioural deficits that correlated well with infarction volumes, while relatively poor correlation between infarction volume and neurobehavioural abnormalities was evident in the photothrombosis model. The results indicate the suitability of the MCAO model for studies on preventive or therapeutic compounds related to functional recovery, although the photothrombosis model might be useful to generate focused lesions leading to the location-related behavioural changes.
    Environmental toxicology and pharmacology. 11/2011; 33(1):60-9.
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    ABSTRACT: Since cyclophosphamide is metabolically activated to teratogenic acrolein and cytotoxic phosphoramide mustard by cytochrome P-450 type 2B (CYP2B), we assessed the effects of licorice, a CYP2B inducer, on the fetal defects induced by cyclophosphamide. Pregnant Sprague-Dawley rats were daily administered with licorice (100 mg/kg) by gavage for 7 days, from the 6th to 12th day of gestation, and intraperitoneally administered with cyclophosphamide (11 mg/kg) 1 hr after the final licorice treatment. On the 20th day of gestation, maternal and fetal abnormalities were determined by Cesarian section. Cyclophosphamide was found to reduce fetal and placental weights without increasing resorption or death. In addition, it induced malformations in live fetuses; 93.8, 41.1, and 100% of the external (skull and limb defects), visceral (cleft palate and ureteric dilatation), and skeletal (acrania, vertebral/costal malformations, and delayed ossification) abnormalities, respectively. When pre-treated with licorice, cyclophosphamide-induced body weight loss and abnormalities of fetuses were remarkably aggravated. Moreover, repeated treatment with licorice greatly increased mRNA expression and activity of hepatic CYP2B. The results indicate that repeated intake of licorice may aggravate cyclophosphamide-induced body weight loss and malformations of fetuses by upregulating CYP2B.
    Birth Defects Research Part B Developmental and Reproductive Toxicology 08/2011; 92(6):553-9. · 1.97 Impact Factor
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    ABSTRACT: Periventricular leukomalacia, specifically characterized as white matter injury, in neonates is strongly associated with the damage of pre-myelinating oligodendrocytes. Clinical data suggest that hypoxia-ischemia during delivery and intrauterine or neonatal infection-inflammation are important factors in the etiology of periventricular leukomalacia including cerebral palsy, a serious case exhibiting neurobehavioral deficits of periventricular leukomalacia. In order to explore the pathophysiological mechanisms of white matter injury and to better understand how infectious agents may affect the vulnerability of the immature brain to injury, novel animal models have been developed using hypoperfusion, microbes or bacterial products (lipopolysaccharide) and excitotoxins. Such efforts have developed rat models that produce predominantly white matter lesions by adopting combined hypoxia-ischemia technique on postnatal days 1-7, in which unilateral or bilateral carotid arteries of animals are occluded (ischemia) followed by 1-2 hour exposure to 6-8% oxygen environment (hypoxia). Furthermore, low doses of lipopolysaccharide that by themselves have no adverse-effects in 7-day-old rats, dramatically increase brain injury to hypoxic-ischemic challenge, implying that inflammation sensitizes the immature central nervous system. Therefore, among numerous models of periventricular leukomalacia, combination of hypoxia-ischemia-lipopolysaccharide might be one of the most-acceptable rodent models to induce extensive white matter injury and ensuing neurobehavioral deficits for the evaluation of candidate therapeutics.
    Laboratory animal research. 06/2011; 27(2):77-84.
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    ABSTRACT: Renal toxicity by melamine in combination with cyanuric acid (1:1) was investigated. Male rats were orally administered melamine plus cyanuric acid (5, 50 or 400 mg/kg each) for 3 days. In contrast to a negligible effect by melamine alone (50 mg/kg, a no-observed-adverse-effect-level: NOAEL), co-administration with cyanuric acid markedly increased the concentrations of blood urea nitrogen and creatinine, as well as kidney weight. A high dose (400 mg/kg) of melamine plus cyanuric acid induced more severe kidney toxicity. The increased blood parameters for kidney toxicity and organ weight lasted longer than 4 days. Combined treatment with melamine and cyanuric acid (50-400 mg/kg each) resulted in many gold-brown crystals and toxic lesions in renal tubules, which were not observed in animals treated with melamine alone (50 mg/kg). These results indicate that only a 3-day exposure to melamine in combination with cyanuric acid causes severe renal damage, even at a NOAEL for melamine found in a 13-week toxicity study. Therefore, it is suggested that the tolerable daily intake or regulatory/management levels of melamine need to be re-considered for cases of co-exposure with cyanuric acid.
    Laboratory animal research. 03/2011; 27(1):25-8.
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    ABSTRACT: Antiulcer effects of pantoprazole, a proton-pump inhibitor, on water-immersion restraint stress (WIRS)-, alcohol (ethanol)- and pylorus ligation-induced gastric ulcers were investigated in male rats. Rats were orally administered with pantoprazole 30 min prior to exposure to various types of ulcer inducers. In stress-induced ulcer model, rats were subjected to WIRS at 22℃ for 4 hours, and the degree of ulcer (in mm) was evaluated. In alcohol-induced ulcer model, rats were orally administered with pure (100%) ethanol (1 mL/kg), and the ulcer lesions were measured 1 hour after ethanol challenge. In pylorus ligation-induced ulcer model, rats were subjected to pylorus ligation, and the degree of erosions and ulcers was scored 17 hours after the operation. Pantoprazole attenuated the ulcer lesions induced by WIRS in a dose-dependent manner, exhibiting a median effective dose (ED(50)) value of 0.78 mg/kg. By comparison, pantoprazole was effective at relatively-high doses for the improvement of ethanol-induced ulcers, showing an ED(50) value of 20.5 mg/kg. Notably, pantoprazole was practically ineffective (ED(50)>50.0) in pylorus ligation model. Taken together, it was confirmed that pantoprazole showed inhibitory activity on gastric ulcers induced by stress and alcohol, but was ineffective on pylorus ligation-induced ulcer. Therefore, the results indicate that proton-pump inhibitors including pantoprazole might reveal highly-different effects according to the type of ulcer inducers, and that the prescription of antiulcer agents should be carefully selected.
    Laboratory animal research. 03/2011; 27(1):47-52.