• Title/Summary/Keyword: Endothelial Cells

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Oxidative Inactivation of Peroxiredoxin Isoforms by H2O2 in Pulmonary Epithelial, Macrophage, and other Cell Lines with their Subsequent Regeneration (폐포상피세포, 대식세포를 비롯한 각종 세포주에서 H2O2에 의한 Peroxiredoxin 동위효소들의 산화에 따른 불활성화와 재생)

  • Oh, Yoon Jung;Kim, Young Sun;Choi, Young In;Shin, Seung Soo;Park, Joo Hun;Choi, Young Hwa;Park, Kwang Joo;Park, Rae Woong;Hwang, Sung Chul
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.1
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    • pp.31-42
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    • 2005
  • Background : Peroxiredoxins (Prxs) are a relatively newly recognized, novel family of peroxidases that reduce $H_2O_2$ and alkylhydroperoxide into water and alcohol, respectively. There are 6 known isoforms of Prxs present in human cells. Normally, Prxs exist in a head-to-tail homodimeric state in a reduced form. However, in the presence of excess $H_2O_2$, it can be oxidized on its catalytically active cysteine site into inactive oxidized forms. This study surveyed the types of the Prx isoforms present in the pulmonary epithelial, macrophage, endothelial, and other cell lines and observed their response to oxidative stress. Methods : This study examined the effect of exogenous, excess $H_2O_2$ on the Prxs of established cell lines originating from the pulmonary epithelium, macrophages, and other cell lines, which are known to be exposed to high oxygen partial pressures or are believed to be subject to frequent oxidative stress, using non-reducing SDS polyacrylamide electrophoresis (PAGE) and 2 dimensional electrophoresis. Result : The addition of excess $H_2O_2$ to the culture media of the various cell-lines caused the immediate inactivation of Prxs, as evidenced by their inability to form dimers by a disulfide cross linkage. This was detected as a subsequent shift to its monomeric forms on the non-reducing SDS PAGE. These findings were further confirmed by 2 dimensional electrophoresis and immunoblot analysis by a shift toward a more acidic isoelectric point (pI). However, the subsequent reappearance of the dimeric Prxs with a comparable, corresponding decrease in the monomeric bands was noted on the non-reducing SDS PAGE as early as 30 minutes after the $H_2O_2$ treatment suggesting regeneration after oxidation. The regenerated dimers can again be converted to the inactivated form by a repeated $H_2O_2$ treatment, indicating that the protein is still catalytically active. The recovery of Prxs to the original dimeric state was not inhibited by a pre-treatment with cycloheximide, nor by a pretreatment with inhibitors of protein synthesis, which suggests that the reappearance of dimers occurs via a regeneration process rather than via the de novo synthesis of the active protein. Conclusion : The cells, in general, appeared to be equipped with an established system for regenerating inactivated Prxs, and this system may function as a molecular "on-off switch" in various oxidative signal transduction processes. The same mechanisms might applicable other proteins associated with signal transduction where the active catalytic site cysteines exist.

The Clinical Significance of Soluble Intercellular Adhesion Molecule-1 sICAM-1) and Soluble Vascular Cell Adhesion Molecule-1(sVCAM-1) in Kawasaki Disease (급성 발열기 및 아급성기 가와사끼병에서 세포부착분자 sICAM-1, sVCAM-1의 임상적 의의)

  • Rhee, Kang Won;Yun, Sin Weon;Lee, Dong Keun;Choi, Eung Sang;Yoo, Byeong Hoon;Lee, Mi Kyung
    • Clinical and Experimental Pediatrics
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    • v.48 no.6
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    • pp.640-648
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    • 2005
  • Purpose : Kawasaki disease(KD) is known as an acute multi-systemic vasculitis with various immunologic abnormalities. Adhesion of leukocyte to endothelial cells is a key event in the sequence of inflammatory response. This study was performed to investigate the clinical significance of serum soluble intercellular adhesion molecule-1(sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in acute and subacute stages of typical KD for diagnostic and prognostic value. Methods : A typical KD group was 32 patients who were hospitalized from Jan. 2002 to Jun. 2004 was enrolled. Control was 16 non-KD patients with febrile illness. sICAM-1 and sVCAM-1 were measured and compared by Echocardiographic and clinical findings and cardiac troponin T and I. Results : sICAM-1 and sVCAM-1 levels of acute KD were significantly elevated over control(P=0.019 vs. P=0.049, respectively) and sICAM-1 was significantly decreased in subacute stage(P=0.0015). sICAM-1 and sVCAM-1 had positive correlation with each other in both stages(P=0.0067, P=0.015, retrospectively). Neither sICAM-1 nor sVCAM-1 correctly reflected the coronary abnormalities and responsiveness to intravenous gammaglobulin(IVGG) in both stages. But sVCAM-1 was significantly increased in the carditis group in both stages(P=0.025, P=0.014, retrospectively) and had a positive correlation with troponin T(r=0.63, P=0.00063). Conclusion : The levels of sICAM-1 and sVCAM-1 were not very useful tools for detecting and predicting subsequent coronary abnormalities and responsiveness to IVGG in KD patients. However, sVCAM-1 appears to play a significant role in carditis of KD. Further studies are needed about various adhesion molecules and cytokines in the pathogenesis of KD.

ATHEROSCLEROSIS, CHOLESTEROL AND EGG - REVIEW -

  • Paik, I.K.;Blair, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.1
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    • pp.1-25
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    • 1996
  • The pathogenesis of atherosclerosis can not be summarized as a single process. Lipid infiltration hypothesis and endothelial injury hypothesis have been proposed and investigated. Recent developments show that there are many points of potential interactions between them and that they can actually be regarded as two phases of a single, unifying hypothesis. Among the many risk factors of atherosclerosis, plasma homocysteine and lipoprotein(a) draw a considerable interest because they are independent indicators of atherogenicity. Triglyceride (TG)-rich lipoproteins (chylomicron and VLDL) are not considered to be atherogenic but they are related to the metabolism of HDL cholesterol and indirectly related to coronary heart disease (CHD). LDL can of itself be atherogenic but the oxidative products of this lipoprotein are more detrimental. HDL cholesterol has been considered to be a favorable cholesterol. The so-called 'causalist view' claims that HDL traps excess cholesterol from cellular membranes and transfers it to TG-rich lipoproteins that are subsequently removed by hepatic receptors. In the so-called 'noncausalist view', HDL does not interfere directly with cholesterol deposition in the arterial wall but instead reflects he metabolism of TG-rich lipoproteins and their conversion to atherogenic remnants. Approximately 70-80% of the human population shows an effective feedback control mechanism in cholesterol homeostasis. Type of dietary fat has a significant effect on the lipoprotein cholesterol metabolism and atherosclerosis. Generally, saturated fatty acids elevate and PUFA lower serum cholesterol, whereas MUFA have no specific effect. EPA and DHA inhibit the synthesis of TG, VLDL and LDL, and may have favourable effects on some of the risk factors. Phospholipids, particularly lecithin, have an antiatherosclerotic effect. Essential phospholipids (EPL) may enhance the formation of polyunsaturated cholesteryl ester (CE) which is less sclerotic and more easily dispersed via enhanced hydrolysis of CE in the arterial wall. Also, neutral fecal steroid elimination may be enhanced and cholesterol absorption reduced following EPL treatment. Antioxidants protect lipoproteins from oxidation, and cells from the injury of toxic, oxidized LDL. The rationale for lowering of serum cholesterol is the strong association between elevation of plasma or serum cholesterol and CHD. Cholesterol-lowing, especially LDL cholesterol, to the target level could be achieved using diet and combination of drug therapy. Information on the link between cholesterol and CHD has decreased egg consumption by 16-25%. Some clinical studies have indicated that dietary cholesterol and egg have a significant hypercholesterolemic effect, while others have indicated no effect. These studies differed in the use of purified cholesterol or cholesterol in eggs, in the range of baseline and challenge cholesterol levels, in the quality and quantity of concomitant dietary fat, in the study population demographics and initial serum cholesterol levels, and clinical settings. Cholesterol content of eggs varies to a certain extent depending on the age, breed and diet of hens. However, egg yolk cholesterol level is very resistant to change because of the particular mechanism involved in yolk formation. Egg yolk contains a factor of factors responsible for accelerated cholesterol metabolism and excretion compared with crystalline cholesterol. One of these factors could be egg lecithin. Egg lecithin may not be as effective as soybean lecithin in lowering serum cholesterol level due probably to the differences of fatty acid composition. However, egg lecithin may have positive effects in hypercholesterolemia by increasing serum HDL level and excretion of fecal cholesterol. The association of serum cholesterol with egg consumption has been widely studied. When the basal or control diet contained little or no cholesterol, consumption of 1 or 2 eggs daily increased the concentration of plasma cholesterol, whereas that of the normolipemic persons on a normal diet was not significantly influenced by consuming 2 to 3 eggs daily. At higher levels of egg consumption, the concentration of HDL tends to increase as well as LDL. There exist hyper-and hypo-responders to dietary (egg) cholesterol. Identifying individuals in both categories would be useful from the point of view of nutrition guidelines. Dietary modification of fatty acid composition has been pursued as a viable method of modifying fat composition of eggs and adding value to eggs. In many cases beneficial effects of PUFA enriched eggs have been demonstrated. Generally, consumption of n-3 fatty acids enriched eggs lowered the concentration of plasma TG and total cholesterol compared to the consumption of regular eggs. Due to the highly oxidative nature of PUFA, stability of this fat is essential. The implication of hepatic lipid accumulation which was observed in hens fed on fish oils should be explored. Nutritional manipulations, such as supplementation with iodine, inhibitors of cholesterol biosynthesis, garlic products, amino acids and high fibre ingredients, have met a limited success in lowering egg cholesterol.

Effect of Pancreatic Polypeptide Family on Cardiovascular Muscle Contractility: 1. Interactions with cyclic nucleotide activators and $K^+$ channel openers in canine cerebral arteries (Pancreatic Polypeptide Family의 심혈관계 근육 수축성에 대한 약리학적 작용: I. 개의 뇌혈관에서 cyclic nucleotide활성제와 칼륨통로개방제와의 상호작용)

  • Kim, Won-Joon;Lee, Kwang-Youn;Ha, Jeoung-Hee;Kwon, Oh-Cheol
    • The Korean Journal of Pharmacology
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    • v.28 no.2
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    • pp.147-162
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    • 1992
  • The objectives of the present experiments were to characterize the effects of the peptides belonging to the pancreatic polypeptide family on the contractility of cerebral arteries and to observe the interactions of these peptides with the cyclic nucleotide activators and the potassium channel openers. Dogs of either sex, $20{\sim}30\;Kg$ in weight, were sacrificed. Basilar and middle cerebral arteries from brain were isolated and prepared for myography in the PSS equilibrated with 95% $O_2$ and 5% $CO_2$ at $37^{\circ}C$. The endothelial cells of the spiral strips were removed by CHAPS solution (0.3% w/v, 15 seconds). 1. PP, PYY and NPY contracted the arterial strips concentration-dependently with a rank order of potency of PYY>NPY>PP. These peptides were 20 to 200 times more potent than norepinephrine, and only PYY showed a greater potency than 5-HT. 2. Cyclic nucleotide activators, forskolin (for cAMP) and sodium nitroprusside (for cGMP) reduced the basal tone and inhibited the PP-, PYY- and NPY- induced contractions by concentration-dependent manners. Forskolin was more potent in reducing basal tone than sodium nitroprusside. 3. Potassium channel openers, RP 49356, P 1060 and BRL 38227 reduced the basal tone concentration-dependently and tended to inhibit the PP-, PYY- and NPY- induced contractions. Notably, BRL 38227 with low concentration $(0.1\;{\mu}M)$ enhanced the contractions induced by those peptides while P 1060 inhibited the contractions concentration-dependently. 4. The combinations of the cyclic nucleotide activators and the potassium channel openers were slightly additive in reducing the basal tone. P 1060 and BRL 38227 enhanced the relaxant effect of sodium nitroprusside significantly. On the PYY-induced contration $(0.1\;{\mu}M)$, $K^+$ channel openers tended to inhibit the inhibitory actions of forskolin and sodium nitroprusside. P 1060 and BRL 38227 antagonized the inhibitory action of sodium nitroprusside significantly. The results of the present study may be summarized that in canine cerebral arteries, not only NPY but also PYY may play a role in a cerebrovascular spasm, and intracellular concentration of either cAMP or cGMP may be involved in the mechanism of vasoconstrictive actions of these peptides, which may be affected either positively or negatively by a $K^+$ channel opener.

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A Study of the "Ikkando Medicine" in Japanese Oriental Medicine (일본(日本) 한방의학(韓方醫學)의 체질의학(體質醫學)인 《일관당의학(一貫堂醫學)》에 관(關)한 고찰(考察))

  • Joh, Kiho;Park, Seong Sik;Terasawa, Katsutoshi;Shimada, Yutaka;Lee, Won Chul
    • Journal of Sasang Constitutional Medicine
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    • v.9 no.1
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    • pp.339-352
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    • 1997
  • The oriental medicine based on the traditional chinese medicine has developed according to the historical and racial character respectively in China, Korea and Japan etcs. Particularly, the distinctive feature of Korea & Japan is characterized by the development of constitutional medicine compared with chinese medicine; Sasang Medicine of Korea and Ikkando Medicine of Japan. The constitutional medicines were so far developed by many clinical doctors, and in recent years much interest has centered on the application of these medicines in regarding originality, easiness and effectiveness etcs in treatment. Thus far only few attempts have been made at Ikkando medicine in Korea, what seems to be lacking, however, is practical application in clinic. Thus authors intend to help the clinical application by introducing Ikkando medicine to Korea oriental medicine through this paper. The Ikkando medicine was established by Dohaku Mori(1869~1931) and was known through the "Kampo Ikkando Medincine" which was published by his disciple, Kaku Yakazu(1893~1966), classified human beings into three types; type of blood stasis, type of stroke and type of allergy. The type of blood stasis may be responsible for factors which have occurred by a state of insufficient bleed circulation and blood stasis causing lesione of endothelial cells, and Tongdosan is mainly administrated. The predisposing factor of stroke's type is known as the excessive diet, and the prevalence of cerebrovascular accident is probably higher. In this type, it is likely that patients are prevented and cured with Bangpungtongsunsan. Allergy's type have three distinct types of childhood, adolescence and adult as to the age. Allergy's type of childhood predisposes patients such as these to upper respiratory infection and tuberculosis etcs, and Sihocheonggansan is frequently administrated. Allergy's type of adolescence has a tendency to rhinitis and infection of face legion etcs, and Heunggyeyeoungyotang is mainly administrated. Allergy's type of adult is subject to urogenital infection, and is more commonly treated with Yongdamsagantang. Judging from the above, we can say with fair certainty that Ikkando Medicine has considerable validity to clinical practice, though it should not be pushed too far.

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The Effects of Nitric Oxide Inhibitor on Hyperdynamic Circulation in Portal Hypertensive Rats (산화 질소 억제제가 문맥 고혈압 쥐의 혈역학 변화에 미치는 영향)

  • Kim, Pill-Young;Jang, Byeong-Ik;Kim, Tae-Nyeun;Chung, Moon-Kwan
    • Journal of Yeungnam Medical Science
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    • v.16 no.2
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    • pp.181-192
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    • 1999
  • Background: Nitric oxide, a vasodilator synthesized from L-arginine by vascular endothelial cells, accounts for the biological activity of endothelium derived relaxing factor. Previous studies demonstrated that nitric oxide inhibitor, $N^{\omega}$-Nitro-L-Arginine(NNA) diminished the hyperdynamic splanchnic and systemic circulation in portal hypertensive rats The present study was done to determine the role of nitric oxide in the development of hyperdynamic circulations in the prehepatic portal hypertensive rat model produced by partial portal vein ligation. Methods: The portal hypertensive rats were divided into water ingestion group and NNA ingestion group. After partial portal vein ligation, NNA ingestion group and water ingestion group received NNA 1mg/kg/day and plain water through the mouth for 14 days, respectively. Cardiac output, mean arterial pressure, organ blood flow and porto-systemic shunting were measured by radioisotope labeled microsphere methods. Vascular resistances were calculated by standard equation. Results: There were significant decreases in mean arterial pressure, increases in cardiac output and cardiac index, and decreases in total systemic and splanchnic vascular resistance in portal hypertensive rats compared to normal control group (p<0.01). Compared to the water ingestion group, significantly increased mean arterial pressure with decreased cardiac output and cardiac index were developed in the NNA ingestion group. Total systemic and splanchnic vascular resistance were significantly increased in the NNA ingestion group compared to water ingestion group (p<0.05). But, there was no significant difference in portal pressure between the two groups. Conclusion: The hemodynamic results of this study indicate that hyperdynamic circulation in prehepatic portal hypertensive rat mode1 was attenuated by ingestion of NNA. Nitric oxide may play an important role in the development of hyperdynamic circulation with splanchnic vasodilation in chronic portal hypertension.

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Changes in Urinary Nitric Oxide in Pediatric Renal Diseases (소아 신장질환에서 소변 내 산화질소의 변화)

  • Kim, Jong-Hwa;Jung, Ji-In;Yim, Hyung-Eun;Hong, Young-Sook;Lee, Joo-Won;Yoo, Kee-Hwan
    • Childhood Kidney Diseases
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    • v.11 no.1
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    • pp.24-31
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    • 2007
  • Purpose : Nitric oxide(NO) is a very potent vasodilator synthesized from L-arginine by endothelial cells. We investigated whether urinary NO excretion was altered in various renal diseases in children and whether urinary NO excretion could be used in predicting pathologic causes and fibrosis in renal diseases in children. Methods : We recruited 48 patients(32 minimal change nephrotic syndrome[MCNS] and 16 vesicoureteral reflux[VUR] patients from the pediatric renal clinic in Korea University Guro Hospital. We measured the concentration of nitrite$(NO_2)$ and nitrate$(NO_3)$ by Griess reaction and that of creatinine(Cr) by Jaffe method in randomized spot urines. We then analyzed the urinary$(NO_2+NO_3)/Cr$ ratios and compared the values between each patient group. Urinary $(NO_2+NO_3)/Cr$ ratios were also evaluated according to the recurrence and the degree of proteinuria at sampling in the MCNS group and compared according to the presence of renal scarring and the grade of reflux in the VUR group. Results : The ratios of urinary$(NO_2+NO_3)/Cr$ were significantly increased in the VUR and MCNS groups, as compared to the control group. In the MCNS group, a higher level of urine $(NO_2+NO_3)/Cr$ was observed In frequent relapse patients(relapse over four times within one year after first diagnosis) and the patients with severe proteinuria at sampling, respectively. The VUR group with renal scars also showed a higher level of urinary$(NO_2+NO_3)/Cr$ compared to that without scars. Conclusions : In summary, VUR may play a role in the pathogenesis of VUR and MCNS. NO also seems to affect proteinuria and renal scar formation. (J Korean Soc Pediatr Nephrol 2007;11:24-31)

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The Suppressive Effects of Integrin Antibodies on the Infection of Hantaan Virus in Fibroblasts (한탄바이러스의 섬유아세포 감염에 대한 Integrin 항체의 억제 효과)

  • Park, Ho-Sun;Kim, Ki-Duk;Kim, Sung-Kwang
    • Journal of Yeungnam Medical Science
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    • v.15 no.1
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    • pp.55-66
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    • 1998
  • Pathophysiological mechanism of hemorrhagic fever with renal syndrome (HFRS) is not fully understood. Major clinical findings of HFRS patients are widespread hemorrhage, acute renal failure and shock. Basic lesion is vascular injury with microvascular hemorrhage and relatively little inflammation. According to autopsy findings, renal medulla shows focal hemorrhage, tubular necrosis and interstitial mononuclear infiltrates. The predominant cell type in the renal and pulmonary interstitium is a fibroblast and it participates in the healing process at the injury site by secreting a large amount of extracellular matrix proteins. Cultured human lung fibroblasts and Mongolian gerbil fibroblasts were known to be good host cells for the hantaan virus. It is possible that not only the endothelial cell but also the fibroblast is a target of Hantaan virus and the fibroblast might be involved in the pathogenesis and the healing process in HFRS. Integrins are adhesion molecules, and act as receptors for many extracellular matrix proteins. Recently, there are many reports that cell surface integrins influence on some viral infections or reversely viruses influence on the expression of integrins. The ${\alpha}_5{\beta}_1$ integrin is a major receptor for the fibronectin which is an important extracellular matrix protein secreted by fibroblasts. In this study, the role of ${\alpha}_5{\beta}_1$ integrin in the infection of Hantaan virus was examined by using anti-${\alpha}_5{\beta}_1$, integrin, anti-${\alpha}_5$ integrin and anti-${\beta}_1$, integrin antibodies in chicken embryo fibroblasts (CEF) and Mongolian gerbil fibroblasts(MGF). The treatment of anti-${\alpha}_5{\beta}_1$, integrin antibody in CEF reduced the virion titers 26.8% and the amount of nucleocapsid N protein 32.6% when compared with control CEF. When MGF were treated with anti-${\alpha}_5$, anti-${\beta}_1$ and anti-${\alpha}_5{\beta}_1$ integrin antibodies, virion titers were reduced by 26.5%, 29.4% and 28.7% and the amount of nucleocapsid N protein were reduced by 65.2%, 59.7% and 72.6%. These results suggested that ${\alpha}_5{\beta}_1$ integrin might act as a receptor for the Hantaan virus or blocking of ${\alpha}_5{\beta}_1$ integrin influences on the viral replication in CEF and MGF. It is also possible that the blocking of only one subunit of integrin represents similar results in that of whole molecule.

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Expression of nitric oxide synthase isoforms and N-methyl-D-aspartate receptor subunits according to transforming growth factor-β1 administration after hypoxic-ischemic brain injury in neonatal rats (신생 백서의 저산소 허혈 뇌손상에서 Transforming Growth Factor-β1 투여에 따른 Nitric Oxide Synthase 이성체와 N-methyl-D-aspartate 수용체 아단위의 발현)

  • Go, Hye Young;Seo, Eok Su;Kim, Woo Taek
    • Clinical and Experimental Pediatrics
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    • v.52 no.5
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    • pp.594-602
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    • 2009
  • Purpose : Transforming growth factor (TGF)-${\beta}1$ reportedly increases neuronal survival by inhibiting the induction of inducible nitric oxide synthase (NOS) in astrocytes and protecting neurons after excitotoxic injury. However, the neuroprotective mechanism of $TGF-{\beta}1$ on hypoxic-ischemic (HI) brain injury in neonatal rats is not clear. The aim of this study was to determine whether $TGF-{\beta}1$ has neuroprotective effects via a NO-mediated mechanism and N-methyl-D-aspartate (NMDA) receptor modulation on perinatal HI brain injury. Methods : Cortical cells were cultured using 19-day-pregnant Sprague-Dawley (SD) rats treated with $TGF-{\beta}1$ (1, 5, or 10 ng/mL) and incubated in a 1% O2 incubator for hypoxia. Seven-day-old SD rat pups were subjected to left carotid occlusion followed by 2 h of hypoxic exposure (7.5% $O_2$). $TGF-{\beta}1$ (0.5 ng/kg) was administered intracerebrally to the rats 30 min before HI brain injury. The expressions of NOS and NMDA receptors were measured. Results : In the in vitro model, the expressions of endothelial NOS (eNOS) and neuronal NOS (nNOS) increased in the hypoxic group and decreased in the 1 ng/mL $TGF-{\beta}1-treated$ group. In the in vivo model, the expression of inducible NOS (iNOS) decreased in the hypoxia group and increased in the $TGF-{\beta}1$-treated group. The expressions of eNOS and nNOS were reversed compared with the expression of iNOS. The expressions of all NMDA receptor subunits decreased in hypoxia group and increased in the $TGF-{\beta}1$-treated group except NR2C. Conclusion : The administration of $TGF-{\beta}1$ could significantly protect against perinatal HI brain injury via some parts of the NO-mediated or excitotoxic mechanism.

Effects of zearalenone on the localization and expression of the growth hormone receptor gene in the uteri of post-weaning piglets

  • Zhou, Min;Yang, Li Jie;Yang, Wei Ren;Huang, Li Bo;Zhou, Xue Mei;Jiang, Shu Zhen;Yang, Zai Bin
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.1
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    • pp.32-39
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    • 2018
  • Objective: In this study, we investigated the adverse effects of dietary zearalenone (ZEA) (0.5 to 1.5 mg/kg diet) on the localization and expression of the growth hormone receptor (GHR) in the uteri of post-weaning gilts and explored alternative mechanism of the reproductive toxicity of ZEA on piglets. Methods: A total of forty healthy piglets (Duroc${\times}$Landrace${\times}$Large White) aged 28 d were selected for study. Piglets were transferred to single cages after 10 days' adaptation on an obstetric table. The animals were allocated to one of four treatments: a normal basal diet supplemented with 0 (Control), 0.5 (ZEA0.5), 1.0 (ZEA1.0), or 1.5 (ZEA1.5) mg/kg purified ZEA, and fed for 35 d after the 10-d adaptation. Analyzed ZEA concentrations in the diets were 0, $0.52{\pm}0.07$, $1.04{\pm}0.03$, and $1.51{\pm}0.13mg/kg$, respectively. At the end of the feeding trial, piglets were euthanized after being fasted for 12 h. Two samples of uterine tissue from each pig were rapidly collected, one of which was stored at $-80^{\circ}C$ for analysis of the relative mRNA and protein expression of GHR, and the second was promptly fixed in Bouin's solution for immunohistochemical analysis. Results: The relative weight of the uteri and thickness of the myometrium and endometrium increased linearly (p<0.001) and quadratically (p<0.001) with an increasing level of ZEA. The results of immunohistochemical analysis indicated that GHR immunoreactive substance was mainly localizated in the cytoplasm of uterine smooth muscle, glandular epithelial, luminal epithelial, stromal, and vascular endothelial cells. In contrast, nuclear staining was rarely observed. The immunoreactive integrated optic density of GHR in the myometrium, luminal epithelium, glandular epithelium, and whole uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA. The mRNA and protein expression of GHR in the uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA. Conclusion: In conclusion, ZEA at a concentration of 0.5 mg/kg was sufficient to significantly thicken the myometrium and endometrium, and at a concentration of 1.0 mg/kg induced a high level of GHR expression to promote growth and development of the uteri. This revealed an alternative molecular mechanism whereby ZEA induces growth and development of the uteri and provides a theoretical basis for the revision of Chinese feed hygiene standards.