• 제목/요약/키워드: C57BL/6mice

검색결과 1,139건 처리시간 0.033초

파킨슨병 동물 모델을 이용한 양릉천(GB34)의 선조체 내 도파민성신경세포 보호 기전 연구 (Neuroprotective Mechanism of Acupuncture at GB34 for Dopaminergic Neurons in the Striatum of a Parkinson's Disease Mouse Model)

  • 전형준;유태원;김동수;권선오;김승태
    • Korean Journal of Acupuncture
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    • 제32권3호
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    • pp.108-115
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    • 2015
  • Objectives : Acupuncture is frequently used as an alternative therapy for Parkinson's disease(PD) in Korea. Using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced Parkinson's disease mouse model, the present study investigated a possible role of acupuncture stimulation at GB34 in suppressing dopaminergic neuronal death and regulating the phosphorylation of protein kinase B(Akt) in substantia nigra(SN) and striatum(ST). Methods : Eight-week-old male C57BL/6 mice were administered intraperitoneally with 30 mg/kg of MPTP at 24-h intervals for 5 days. Acupuncture stimulation at GB34 or SI3 was performed once a day for 12 days consecutively from the first MPTP injection. After the last acupuncture stimulation, pole test was performed to assess the effect of the acupuncture stimulations. Dopaminergic neuronal survival in the SN and the ST, dopamine transporter( DAT) and caspase-3 expression in the ST were evaluated by immunohistochemistry. The phosphorylations of Akt in the SN and the ST were measured by Western blotting. Results : MPTP administration caused behavioral impairment and dopaminergic neuronal death in the SN and the ST. It also decreased DAT expression and increased caspase-3 expression in the ST. Acupuncture stimulation at GB34 alleviated these MPTP-induced impairments. Moreover, MPTP suppressed Akt phosphorylation in the SN and the ST, whereas acupuncture stimulation at GB34 alleviated the phosphorylation in the SN. Conclusions : These results indicate that acupuncture stimulation at GB34 can inhibit MPTP-induced dopaminergic neuronal death and alleviate the Akt phosphorylation in the SN, suggesting a possible role for acupuncture in the treatment of PD.

Ginsenoside Ro, an oleanolic saponin of Panax ginseng, exerts anti-inflammatory effect by direct inhibiting toll like receptor 4 signaling pathway

  • Xu, Hong-Lin;Chen, Guang-Hong;Wu, Yu-Ting;Xie, Ling-Peng;Tan, Zhang-Bin;Liu, Bin;Fan, Hui-Jie;Chen, Hong-Mei;Huang, Gui-Qiong;Liu, Min;Zhou, Ying-Chun
    • Journal of Ginseng Research
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    • 제46권1호
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    • pp.156-166
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    • 2022
  • Background: Panax ginseng Meyer (P. ginseng), a herb distributed in Korea, China and Japan, exerts benefits on diverse inflammatory conditions. However, the underlying mechanism and active ingredients remains largely unclear. Herein, we aimed to explore the active ingredients of P. ginseng against inflammation and elucidate underlying mechanisms. Methods: Inflammation model was constructed by lipopolysaccharide (LPS) in C57BL/6 mice and RAW264.7 macrophages. Molecular docking, molecular dynamics, surface plasmon resonance imaging (SPRi) and immunofluorescence were utilized to predict active component. Results: P. ginseng significantly inhibited LPS-induced lung injury and the expression of proinflammatory factors, including TNF-α, IL-6 and IL-1β. Additionally, P. ginseng blocked fluorescencelabeled LPS (LPS488) binding to the membranes of RAW264.7 macrophages, the phosphorylation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). Furthermore, molecular docking demonstrated that ginsenoside Ro (GRo) docked into the LPS binding site of toll like receptor 4 (TLR4)/myeloid differentiation factor 2 (MD2) complex. Molecular dynamic simulations showed that the MD2-GRo binding conformation was stable. SPRi demonstrated an excellent interaction between TLR4/ MD2 complex and GRo (KD value of 1.16 × 10-9 M). GRo significantly inhibited LPS488 binding to cell membranes. Further studies showed that GRo markedly suppressed LPS-triggered lung injury, the transcription and secretion levels of TNF-α, IL-6 and IL-1β. Moreover, the phosphorylation of NF-κB and MAPKs as well as the p65 subunit nuclear translocation were inhibited by GRo dose-dependently. Conclusion: Our results suggest that GRo exerts anti-inflammation actions by direct inhibition of TLR4 signaling pathway.

Hypolipidemic effect of Salicornia herbacea in animal model of type 2 diabetes mellitus

  • Hwang, Ji-Yeon;Lee, Soo-Kyung;Jo, Ja-Rim;Kim, Mi-Eun;So, Hyun-Ah;Cho, Chang-Woo;Seo, Young-Wan;Kim, Jung-In
    • Nutrition Research and Practice
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    • 제1권4호
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    • pp.371-375
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    • 2007
  • To control blood glucose level as close to normal is a major goal of treatment of diabetes mellitus. Hyperglycemia and hyperlipidemia are the major risk factors for cardiovascular complications, the major cause of immature death among the patients with type 2 diabetes. The purpose of this study is to determine the hypoglycemic and hypolipidemic effects of Salicornia herbacea in animal model of type 2 diabetes and to investigate the possible mechanisms for the beneficial effects of S. herbacea. S. herbacea was extracted with 70% ethanol and desalted with 100% ethanol. Three week-old db/db mice (C57BL/KsJ, n=16) were fed AIN-93G semipurified diet or diet containing 1% desalted ethanol extract of S. herbacea for 6 weeks after 1 week of adaptation. Fasting plasma glucose, triglyceride, and total cholesterol were measured by enzymatic methods and blood glycated hemoglobin ($HbA_{1C}$) by the chromatographic method. Body weight and food intake of S. herbacea group were not significantly different from those of the control group. Fasting plasma glucose and blood glycated hemoglobin levels tended to be lowered by S. herbacea treatment. Consumption of S. herbacea extract significantly decreased plasma triglyceride and cholesterol levels (p<0.05). The inhibition of S. herbacea extract against yeast ${\alpha}$-glucosidase was 31.9% of that of acarbose at the concentration of 0.5 mg/mL in vitro. The inhibitory activity of ethanol extract of S. herbacea against porcine pancreatic lipase was 59.0% of that of orlistat at the concentration of 0.25 mg/mL in vitro. Thus, these results suggest that S. herbacea could be effective in controlling hyperlipidemia by inhibition of pancreatic lipase in animal model of type 2 diabetes.

Ginsenoside F2 attenuates chronic-binge ethanol-induced liver injury by increasing regulatory T cells and decreasing Th17 cells

  • Kim, Myung-Ho;Kim, Hee-Hoon;Jeong, Jong-Min;Shim, Young-Ri;Lee, Jun-Hee;Kim, Ye Eun;Ryu, Tom;Yang, Keungmo;Kim, Kyu-Rae;Jeon, Byeong-Min;Kim, Sun Chang;Jung, Jae-Kwang;Choi, Jae-Kap;Lee, Young-Sun;Byun, Jin-Seok;Jeong, Won-Il
    • Journal of Ginseng Research
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    • 제44권6호
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    • pp.815-822
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    • 2020
  • Background: Recently, beneficial roles of ginsenoside F2 (GF2), a minor constituent of Panax ginseng, have been demonstrated in diverse inflammatory diseases. However, its roles in alcoholic liver inflammation and injury have not been clearly understood. Here, we investigated the underlying mechanism by which GF2 ameliorated alcoholic liver injury. Methods: To induce alcoholic liver injury, C57BL/6J wild type (WT) or interleukin (IL)-10 knockout (KO) mice were orally administered with ethanol (3 g/kg) or ethanol-containing GF2 (50 mg/kg) for 2 wk. Liver injury and infiltration of macrophages and neutrophils were evaluated by serum biochemistry and immunohistochemistry, respectively. The changes of hepatic immune cells were assessed by flow cytometry and polymerase chain reaction analysis. In vitro differentiation of naïve T cells was performed. Results: GF2 treatment significantly attenuated alcoholic liver injury, in which infiltrations of inflammatory macrophages and neutrophils were decreased. Moreover, the frequencies of Foxp3+ regulatory T cells (Tregs) increased but IL-17-producing T (Th17) cells decreased in GF2-treated mice compared to controls. Furthermore, the mRNA expression of IL-10 and Foxp3 was significantly increased, whereas IL-17 mRNA expression was suppressed in GF2-treated mice. However, these beneficial roles of GF2 were not observed in GF2-treated IL-10 KO mice, suggesting a critical role of IL-10. Similarly, GF2 treatment suppressed differentiation of naïve T cells into Th17 cells by inhibiting RORgt expression and stimulating Foxp3 expression. Conclusion: The present study suggests that GF2 treatment attenuates alcoholic liver injury by increasing IL-10 expression and Tregs and decreasing IL-17 expression and Th17 cells.

연년익수고본단(延年益壽固本丹)의 육모효능(育毛效能)에 대한 면역조직화학적 연구 (Immunohistochemical Study on Hair Growth Promoting Effect of Yonnyuniksoogobon-dan)

  • 정춘근;심은섭;이창열;김범회;김성준;강희;손낙원
    • 대한한의학회지
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    • 제31권2호
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    • pp.48-63
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    • 2010
  • Objectives: Yonnyuniksoogobon-dan (Yan Nian Yi Shou Gu Ben Dan 延年益壽固本丹) is composed of 11 herbs (Polygoni Mutiflori Radix, Lycii Radicis Cortex, Polia, Rehmanniae Radix, Rehmanniae Radix Preparat, Asparagi Radix, Liriopis Tuber, Lycii Fructus, Acori Graminei Rhizoma, Angelicae Acutiloba Radix, and Pini Folium) based on Yonryunggobon-dan (Yan Ling Gu Ben Dan 延齡固本丹) and Yonnyuniksoobulrho-dan (Yan Nian Yi Shou Bu Lao Dan 延年益壽不老丹). This study evaluated hair growth promoting effect of Yonnyuniksoogobon-dan on the shaved C57BL/6 mice. Methods: Yonnyuniksoogobon-dan was treated by oral administration (Sample I) and oral administration plus skin application (Sample II) once a day for 12 days. Hair regrowth was photographically and histologically determined during the experimental period. Hair growth cycle related factors (EGF, TGF-${\beta}1$) and vascular factors (VEGF, iNOS) were also determined with immunohistochemistry. Results: 1. On gross observation of hair regrowth, Sample I and Sample II groups demonstrated acceleration of hair regrowth. 2. The hair regrowth index of the Sample I group increased significantly from 7 days (P<0.05) to 12 days (P<0.01) after the shave while that of the Sample II group significantly increased at 12 days (P<0.05). 3. On histological observation, both Sample I and Sample II groups demonstrated histological improvement and increases of number and diameter of the hair follicles. 4. EGF expressions on the root sheath of hair follicles were up-regulated in both Sample I and Sample II groups. 5. TGF-${\beta}1$ expressions on the root sheath of hair follicles were not regulated in Sample I or Sample II groups. 6. VEGF expressions in the surrounding tissues of hair follicles were up-regulated in both Sample I and Sample II groups. 7. iNOS expressions in the surrounding tissues of hair follicles were down-regulated in both Sample I and Sample II groups. Conclusions: These results suggest that Yonnyuniksoogobon-dan has hair growth-promoting activity and these effects relate to up-regulations of EGF and VEFG expressions and down-regulations of TGF-${\beta}1$ and iNOS expressions on hair roots.

Expression of SDF-$1{\alpha}$ and leptin, and their effect on expression of angiogenic factors in mouse ovaries

  • Park, Min-Jung;Park, Sea-Hee;Lee, Su-Kyung;Moon, Sung-Eun;Moon, Hwa-Sook;Joo, Bo-Sun
    • Clinical and Experimental Reproductive Medicine
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    • 제38권3호
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    • pp.135-141
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    • 2011
  • Objective: Ovarian angiogenesis plays an important role in folliculogenesis. However, little is known about the expression of angiogenic factors during follicular development according to female age. Stromal cell derived factor-$1{\alpha}$ (SDF-$1{\alpha}$) plays a role in granulosa cell survival and embryo quality as an angiogenic chemokine. Leptin is also involved in folliculogenesis and angiogenesis. This study examined expression of SDF-$1{\alpha}$ and leptin, and their effects on the expression of angiogenic factors in the ovary during follicular development according to female age. Methods: Ovaries were collected from C57BL mice of two age groups (6-9 weeks and 24-26 weeks) at 6, 12, 24, and 48 hours after 5 IU pregnant mare's serum gonadotropin (PMSG) injection. The expression of ovarian SDF-$1{\alpha}$ and leptin mRNA was evaluated by RT-PCR. In the organ culture experiment, the ovaries were cultured in transwell permeable supports with Waymouth's medium treated with various doses of SDF-$1{\alpha}$(50-200 ng/mL) or leptin (0.01-1 ${\mu}g$/mL) for 7 days. Then, mRNA expression of vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS), and visfatin were examined in the cultured ovaries. Results: Expression of SDF-$1{\alpha}$ and leptin in the ovary was significantly lower in the aged mouse group compared to the young mouse group ($p$ <0.05). Expression of these two factors increased with follicular development after PMSG administration. SDF-$1{\alpha}$ treatment stimulated visfatin expression in a dose-dependent manner, while leptin treatment significantly increased eNOS expression. Conclusion: These results suggest that decrease of ovarian SDF-$1{\alpha}$ and leptin expression may be associated with aging-related reduction of ovarian function. SDF-$1{\alpha}$ and leptin may play a role in follicular development by regulating the expression of angiogenic factors in mouse ovaries.

택사탕의 항산화와 혈중지질에 대한 효과 (The Effects of Taeksa-tang on Blood Lipid Profile and Anti Oxidation)

  • 이윤진;이은별;김현지;양두화;김영준;안희덕
    • 한방재활의학과학회지
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    • 제31권2호
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    • pp.1-14
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    • 2021
  • Objectives We evaluated the improving effects of Taeksa-tang (TST) using 3T3-L1 cells and C57BL/6 mice were fed on a high-fat diet. Methods The anti-radical activities of TST were studied using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid). The content of total polyphenol was measured using Folin-Ciocalteu reagent, whereas aluminum chloride colorimetric method was used for the content of total flavonoid. Moreover, the factors related to lipid profile and the protein expressions such as 𝛽-oxidation and anti-oxidant enzyme were analyzed using serum and western blotting of 3T3-L1 cells. Additionally, we examined lipolysis through glycerol appearance in mouse adipose tissue. Results TST treatment showed strong free radical scavenging activities with half maximal inhibitory concentration and the presence of a amount of total polyphenol and total flavonoid. TST treatment significantly increased factors related to 𝛽-oxidation such as carnitine palmitoyl transferase-1 and uncoupling protein 2 via the phosphorlyation of liver kinase B1 (LKB1) and AMP-activated protein kinase (AMPK). Moreover, the protein expressions of anti-oxidant enzyme and lipolysis were significantly elevated by TST administration. In addition, TST supplementation lowered serum malondialdehyde, triglyceride, and total cholesterol levels compared with the control group. Taken together, these data suggest that TST treatment regulated lipid parameters via the increase of 𝛽-oxidation by LKB1-AMPK signaling pathway. Conclusions TST may have a potential remedy in the prevention and treatment of obesity. Therefore, this study may provide the scientific basis for TST use.

MPTP로 유도된 파킨슨병 생쥐 모델에 대한 시호계지탕, 시호소간탕, 시호청간탕의 신경세포 보호 효과 비교 연구 (Comparative Study of the Neuroprotective Effect of Sihogyeji-tang, Sihosogan-tang, and Sihocheonggan-tang on an MPTP-Induced Parkinson's Disease Mouse Model)

  • 서지은;이한울;배창환;윤동학;김희영;김승태
    • Korean Journal of Acupuncture
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    • 제40권3호
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    • pp.90-98
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    • 2023
  • Objectives : Parkinson's disease (PD) is the second most common neurodegenerative disorder worldwide and is characterized by the loss of the dopaminergic neurons in the substantia nigra (SN). In a previous in vitro study, we demonstrated that Sihogyeji-tang (SG), Sihosogan-tang (SS), and Sihocheonggan-tang (SC) have the potential to be candidate medicines for PD. This study aimed to compare the neuroprotective effect of SG, SS, and SC using 1-methyl-4-phenyl-1,2,3,6-tetrahydrophridine (MPTP)-induced PD mouse model. Methods : Eight-week-old male C57BL/6 mice were intraperitoneally administered with 30 mg/kg of MPTP for 5 days and orally administered SG, SS and SC for 12 days from the first MPTP injection. Motor function was assessed using the pole test and the rotarod test. Dopaminergic neuronal survival in the SN and striatum was evaluated through tyrosine-hydroxylase immunohistochemistry. Results : MPTP administration resulted in behavioral impairment and dopaminergic neuronal death in the SN and striatum. In the pole test, treatment with SG, SS, and SC alleviated the MPTP-induced motor dysfunction on day 5 and 12. In the rotarod test, SS and SG alleviated the MPTP-induced motor dysfunction on day 5, while only SS showed improvement on day 12. SS and SG significantly protected dopaminergic neurons in the SN from MPTP toxicity, and all three compounds (SG, SS, and SC) showed significant protection in the striatum. Notably, SS demonstrated superior efficacy in suppressing MPTP-induced motor dysfunction and dopaminergic neuronal death compared to SG and SC. Conclusions : These findings suggest that SS is the most effective formula among SG, SS, and SC for PD, indicating its potential role in the treatment of PD.

Phytohemagglutinin-P 첨가(添加)에 따른 생쥐배(胚)의 시험관내(試驗管內) 응집(凝集)과 배양(培養)에 관하여 (Study on In Vitro Aggregation and Culture of Mouse Embryos by Phytohemagglutinin-P)

  • 박항균;류재웅
    • Current Research on Agriculture and Life Sciences
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    • 제7권
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    • pp.83-97
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    • 1989
  • 본 실험은 일정한 발달단계(發達段階)에 있는 생쥐배(胚)를 응집시킬때 세포응집소인 Phytohemagglutinin-P(PHA-P)를 첨가 라화배(裸化胚)의 응집율과 응집된 배(胚)를 in vitro에서 배양하였을때의 배양율 및 적당한 PHA-P의 첨가농도를 조사하여 Chimera배(胚)를 생산하는데 필요한 기초지식을 얻기 위하여 실시(實施)하였다. Albino BALB/C와 CBA계통 및 C57BL 계통의 생쥐에 pregnant mare Serum gonadotropin와 human chorionic gonadotropin를 투여하여 과배란 생쥐에 PMSG와 hCG를 투여하여 과배란을 유기, 회수된 생쥐의 4세포기, 8세포기 및 상실배기 수정란을 1.0% Protease 용액으로 투명대를 제거(除去)하고 PHA-P를 첨가한 배양액에서 미세한 초자봉(硝子棒)으로 계통(系統)이 다른 두 계통(系統)의 생쥐의 배(胚)를 응집시킨 다음 응집된 배를 $37^{\circ}C$, 5% $CO_2$, 95% Air의 배양기 조건하에서 13~50 시간 배양하면서 Chimera배(胚)의 발달상태를 조사하였다. 본(本) 실험에서 얻어진 결과를 요약하면 다음과 같다. 1. 1.0% Protease 또는 1.0% Protease 및 $5ug/m{\ell}$ PHA-P가 첨가된 산성 Tyrode액에서 투명대를 제거한 라화배(裸化胚)를 배반포까지 배양했을때 유의차는 없었으나 4세포기배와 8세포기배 보다 상실기배가 더 잘 발달되었으며 또한 PHA-P를 첨가하였을때가 첨가하지 아니한 때 보다 다소 좋은 경향을 보였다. 2. PHA-P $2ug/m{\ell}$첨가시 4세포기, 8세포기 및 상실기배의 응집율은40.0~82.0%, $5ug/m{\ell}$첨가시에는 52.0~94.0%, $10ug/m{\ell}$ 첨가시에는 48.0~96.0%로 배(胚)의 발달단계(發達段階)에 따라서는 4세포기, 8세포기가 상실배기 보다 유의적으로 높았다 (P<.05). PHA-P의 처리수준에 의한 응집율에 있어서는 5 또는 $10ug/m{\ell}$첨가구가 $2ug/m{\ell}$첨가구 보다 조금 높게 나타났으나 유의차는 없었다. 3. 응집배의 상실배까지의 배양율은 PHA-P의 각(各) 수준간 및 각(各) 세포기간에 유의차가 인정되지 않았다. 응집배의 배반포까지의 배양율은 PHA-P 수준사이에는 유의차가 없었으나 4세포기와 8세포기의 배(胚)는 상실기 배(胚)보다 유의적으로 높은 배양율을 보였다 (P<.05). 4. 응집된 배(胚)가 배반포까지 발달하는데 소요되는 평균시간은 4세포기배가 38.5~40시간, 8세포기배가 26~27시간, 상실기배가 19~20시간이었다. 5. 응집율은 34.0~94.0%의 범위로서 PHA-P를 첨가할때 응집율이 더 좋은 경향을 보였으나 유의성은 인정되지 않았다. 4세포기와 8세포기의 배(胚)가 상실기배 보다 유의적으로 높았다(P<.05). 6. 응집배의 상실배까지의 발달율은 4세포기배가 52.7~84.7%, 8세포기배가 73.8~872% 였으며 세포기 사이에는 유의차는 나타나지 않았다. 그러나 PHA-P를 첨가한 것이 발달이 더 좋았다. 7. 응집배의 배반포까지의 발달율은 4세포기의 배(胚)가 41.7~77.7%, 8세포기의 배(胚)는 78.7~83.0% 상실기배가 0~19.2%였으며 4세포기의 PHA-P 처리가 미처리(未處理) 보다 유의적으로 높았다(P<.05). PHA-P를 처리했을 때 4세포기와 8세포기가 상실기의 배(胚) 보다 더 높은 발달율을 보였다.

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H. pylori Infection 감염과 위암 발생 (H. pylori Infection and Gastric Carcinogenesis)

  • 한상욱;조용관;정재연;박현진;김영배;남기택;김대용;주희재;최준혁;김진홍;이기명;김명욱;함기백
    • Journal of Gastric Cancer
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    • 제2권2호
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    • pp.73-80
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    • 2002
  • In spite the fact that H. pylori infection might be the causative organisms of acute and chronic gastritis, peptic ulcer diseases and the definition as the class I carcinogen by WHO IARC, still debates exist about the relationship between H. pylori and gastric carcinogenesis. Epidemiological and animal studies demonstrated a link between gastric cancer and chronic infection with H, pylori, but the exact mechanism responsible for the development of gastric cancer in H. pylori-infected patients still remain obscure. In order to declare the clear association, definate evidences like that decrement in the incidence of gastric cancer after the eradication of H. pylori in designated area compared to noneradicated region or the blockade of specific mechanism acting on the carcinogenesis by H. pylori infection. The other way is to identify the upregulating oncogenes or downregulating tumor suppressor genes specifically invovled in H. pylori-associated carcinogenesis. For that, we established the animal models using C57BL/6 mice strain. Already gastric carcinogenesis was developed in Mongolian gerbils infected with H. pylori, but there has been no development of gastric cancer in mice model infected with H. pylori after long-term evaluation. Significant changes such as atrophic gastritis were observed in mice model. However, we could observe the development of mucosal carcinoma in the stomach of transgenic mice featuring the loss of TGF-beta sig naling by the expressions of dominant negative forms of type II receptor specifically in the stomach. Moreover, the incidence of gastric adenocarcinoma was significantly increased in group administered with both MNU and H. pylori infection than MNU alone, signifying that H. pylori promoted the gastric carcinogenesis and there might be host susceptibility genes in H. pylori-associated gastric carcinogenesis. Based on the assumption that chronic, uncontrolled inflammation might predispose to carcinogenesis, there have been several evidences showing chronic atrophic gastritis predisposed to gastric carcinogenesis in H. pylori infection. Although definite outcome of chemoprevention was not drawn after the longterm administration of anti-inflammatory drug in H. pylori infection, the actual incidence of atrophic gastritis and molecular evidence of chemoprevention could be obtained. Selective COX-2 inhibitor was effective in decreasing the development of gastric carcinogenesis provoked by H. pylori infection and carcinogen like in chemoprevention of colon carcinogenesis.

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