• 생명과학회지
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• 제21권2호
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• pp.242-250
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• 2011

본 연구에서는 C2C12 근육 세포에서 IGF-I이 리간드 비의존적으로 엔드로젠 수용체 coactivator 유전자 발현에 미치는 영향에 대해 알아보았다. 그 결과 IGF-I 이 리간드 비의존적으로 엔드로젠 수용체의 coactivator인 GRIP-1, SRC-1, ARA70 유전자들의 단백질과 mRNA 발현을 증가시켰으며, p38 MAPK와 ERK1/2 신호전달 경로 억제제인 SB203580과 PD98059를 IGF-I과 함께 처리한 결과 IGF-I에 의한 엔드로젠 수용체 coactivator 유전자 발현의 증가를 감소시켰음을 알 수 있었다. 엔드로젠 수용체 coactivator가 엔드로젠 물질이 없이도 IGF-I에 의해 발현이 증가하였다는 사실은 운동에 의해 근육에서 분비가 증가하는 IGF-I이 리간드 비의존적으로 근육 세포에서 엔드로젠 수용체 활성화 안정에 기여하는 엔드로젠 수용체 coactivator를 활성화 시킬 수 있다는 사실을 증명 하였다는데 의의가 있다고 사료된다. 또한, IGF-I의 하부신호전달 경로로 잘 알려진 p38 MAPK와 ERK1/2 신호전달 경로를 차단하였을 때는 발현이 억제되었는데 이를 통해 IGF-I이 근육세포 내에서 p38 MAPK, ERK1/2 경로를 통해 엔드로젠 수용체 coactivator 발현에 중요한 역할을 한다는 사실을 확인할 수 있었다. 이러한 결과는 근육에서 중요한 기능을 담당하는 IGF-I이 엔드로젠 수용체 coactivator 유전자 발현을 조절하는 기능이 있으며 이러한 IGF-I에 의한 리간드 비의존적인 엔드로젠 수용체 coactivator 유전자 발현 조절에 있어 p38 MAPK와 ERK1/2는 필수적인 신호전달 경로임을 확인하였다는 데서 그 의의가 있다고 할 수 있겠다. 향후 다양한 성장인자들에 의한 coactivator 발현에 관한 연구를 비롯하여, corepressor의 발현 억제 기능 및 신호전달 경로에 관한 연구가 추가적으로 이루어져야 할 것이다.

• 생명과학회지
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• 제24권5호
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• pp.476-484
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• 2014

비만은 감염원 없이 진행되는 낮은 수준의 만성적인 전신성 염증상태로 간주되며, 만성대사질환의 원인이 된다. 본 연구에서는 미나리를 발효하여 만든 식초가 3T3-L1 지방전구세포의 분화 및 RAW 264.7 세포에서의 항염증 효과에 미치는 영향을 확인하였다. MDI (IBMX, dexamethasone, insulin)에 의해 분화가 유발된 3T3-L1 지방전구세포에 대한 미나리 식초의 분화 억제능을 Oil-red-O staining을 통해 확인하였으며, western blot법을 통해 지방세포 형성 시 중요한 전사인자인 peroxisome proliferator-activated receptor-${\gamma}$ (PPAR-${\gamma}$)와 CCAAT-enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$)의 발현을 감소시키는 것으로 나타났다. 또한, 미나리 식초가 lipopolysaccharide (LPS)에 의해 염증이 유발 된 RAW 264.7 세포의 nitric oxide (NO) 생성을 억제시켰으며, inducible NO synthase (iNOS)와 cyclooxygenase-2 (COX-2)의 단백질 발현을 감소시키는 것을 확인하였다. 이러한 결과들을 통해 미나리 발효 식초는 지방세포 분화와 염증 억제 효과를 가지고 있음을 확인하였다. 따라서 미나리 발효 식초는 대사성 질환을 예방할 수 있는 천연물 소재로 이용 가능할 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4067-4073
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• 2012

Obesity is an established risk factor for colorectal cancer. Pioglitazone is a peroxisome proliferator activated receptor$receptor{\gamma}$ ($PPAR{\gamma}$) agonist that induces differentiation in adipocytes and induces growth arrest and/or apoptosis in vitro in several cancer cell lines. In the present study, we investigated the effect of pioglitazone on the development of azoxymethane-induced colon aberrant crypt foci (ACF) in KK-$A^{\mathcal{Y}}$ obesity and diabetes model mice, and tried to clarify mechanisms by which the $PPAR{\gamma}$ ligand inhibits ACF development. Administration of 800 ppm pioglitazone reduced the number of colon ACF/mouse to 30% of those in untreated mice and improved hypertrophic changes of adipocytes in KK-$A^{\mathcal{Y}}$ mice with significant reduction of serum triglyceride and insulin levels. Moreover, mRNA levels of adipocytokines, such as leptin, monocyte chemoattractant protein-1 and plasminogen activator inhibitor-1, in the visceral fat were decreased. PCNA immunohistochemistry revealed that pioglitazone treatment suppressed cell proliferation in the colorectal epithelium with elevation of p27 and p53 gene expression. These results suggest that pioglitazone prevented obesity-associated colon carcinogenesis through improvement of dysregulated adipocytokine levels and high serum levels of triglyceride and insulin, and increase of p27 and p53 mRNA levels in the colorectal mucosa. These data indicate that pioglitazone warrants attention as a potential chemopreventive agent against obesity-associated colorectal cancer.

• Asian-Australasian Journal of Animal Sciences
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• 제31권4호
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• pp.595-606
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• 2018

Objective: The Fusarium mycotoxins of deoxynivalenol (DON) and zerolenone (ZEN) cause health hazards for both humans and farm animals. Therefore, the main intention of this study was to reveal DON and ZEN effects on the mRNA expression of pro-inflammatory cytokines and other immune related genes in the liver of piglets. Methods: In the present study, 15 six-week-old piglets were randomly assigned to the following three different dietary treatments for 4 weeks: control diet, diet containing 8 mg DON/kg feed, and diet containing 0.8 mg ZEN/kg feed. After 4 weeks, liver samples were collected and sequenced using RNA-Seq to investigate the effects of the mycotoxins on genes and gene networks associated with the immune systems of the piglets. Results: Our analysis identified a total of 249 differentially expressed genes (DEGs), which included 99 upregulated and 150 downregulated genes in both the DON and ZEN dietary treatment groups. After biological pathway analysis, the DEGs were determined to be significantly enriched in gene ontology terms associated with many biological pathways, including immune response and cellular and metabolic processes. Consistent with inflammatory stimulation due to the mycotoxin-contaminated diet, the following Kyoto encyclopedia of genes and genomes pathways, which were related to disease and immune responses, were found to be enriched in the DEGs: allograft rejection pathway, cell adhesion molecules, graft-versus-host disease, autoimmune thyroid disease (AITD), type I diabetes mellitus, human T-cell leukemia lymphoma virus infection, and viral carcinogenesis. Genome-wide expression analysis revealed that DON and ZEN treatments downregulated the expression of the majority of the DEGs that were associated with inflammatory cytokines (interleukin 10 receptor, beta, chemokine [C-X-C motif] ligand 9), proliferation (insulin-like growth factor 1, major facilitator superfamily domain containing 2A, insulin-like growth factor binding protein 2, lipase G, and salt inducible kinase 1), and other immune response networks (paired immunoglobulin-like type 2 receptor beta, Src-like-adaptor-1 [SLA1], SLA3, SLA5, SLA7, claudin 4, nicotinamide N-methyltransferase, thyrotropin-releasing hormone degrading enzyme, ubiquitin D, histone $H_2B$ type 1, and serum amyloid A). Conclusion: In summary, our results demonstrated that high concentrations DON and ZEN disrupt immune-related processes in the liver.

• Clinical and Experimental Reproductive Medicine
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• 제26권3호
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• pp.331-338
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• 1999

The purposes of this study were to evaluate the effects of insulin-like growth factor (IGF)s in peritoneal fluid (PF) from patients with and without endometriosis on the proliferation of endometrial stromal cells and to investigate the effects of type I IGF receptor antibody on the response of endometrial stromal cells to PF from patients with endometriosis. IGFs in PF from patients with endometriosis (n=14) and without endometriosis (n=10) were measured by immunoradiometric assay and PF samples were divided into low IGF-I PF group (less than 85 ng/ml) and high IGF-I PF group (more than 85 ng/ml). Endometrial stromal cells from patients without endometriosis were cultured in serum free media in the presence or absence of 1 % PF and thymidine incorporation test were used to evaluate the proliferation of endometrial stromal cells. Also cultures were incubated with type I IGF receptor monoclonal antibody (${\alpha}IR_3$) before adding PF. PF from patients with endometriosis and without endometriosis increased thymidine incorporation in endometrial stromal cells. In patients with endometriosis, high IGF-I PF group had high IGF-II levels and resulted in higher thymidine incorporation than low IGF-I PF group but no significant difference in increase in thymidine incorporation between high IGF-I and low IGF-I PF group was noted in patients without endometriosis. There was not a significant correlation between increase in thymidine incorporation and IGF-I levels in PF from patients without endometriosis but in PF from patients with endometriosis. Preincubation with ${\alpha}IR_3$ significantly inhibited the mitogenic response of endometrial stromal cells to PF. Our data indicate that IGF-I in PF may be involved in the growth of ectopic endometrium in patients with endometriosis.

• 한국콘텐츠학회논문지
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• 제9권4호
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• pp.355-363
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• 2009

비정상적인 미토콘드리아에 의해 산화 스트레스가 증가하면 세포내 신호전달 및 유전자 발현에 손상을 일으켜 인슐린 저항성이나 당뇨병 등의 여러 질환들을 유발한다. 그런데 자식작용은 산화 스트레스로 기능이 저하된 미토콘드리아를 제거하여 인슐린 저항성 등을 억제해준다. 한편 운동도 미토콘드리아 생합성을 강화시켜 조직의 기능저하나 퇴행을 회복시켜준다. 따라서 운동과 자식작용이 서로 연관되어 미토콘드리아 생합성을 유도하는 신호체계로 작용할 가능성이 있고, 이 연구를 통해 운동 혹은 AICAR (aminoimidazole-4-carboxamide-1-${\beta}$-D-ribofuranoside)처치로 활성 화된 AMPK(5'-AMP- activated protein kinase) 신호전달체계가 미토콘드리아 생합성을 증가시키는 경로에 자식작용이 관여하는지의 여부를 확인하고자 하였다. 연구결과에 따르면, 6시간의 급성운동으로 쥐의 골격근에서 PGC-1(peroxisome proliferator-activated receptor gamma coactivator 1)과 mtTFA (mitochondrial transcription factor A)의 mRNA 발현이 유의하게 증가하였다. 하지만 자식작용 표지제인 LC3(microtubule-associated proteinl light chain 3)의 mRNA 발현은 증가경향을 나타냈지만 유의하지 않았다. 한편 C2C12 근세포에서도 AICAR 처치에 의해 PGC-1, mtTFA mRNA 발현이 모두 증가하였지만, 이러한 증가는 LC3 SiRNA에 의해서 억제되지 않는 것으로 나타났다. 이러한 결과들을 통해 자식작용은 AMPK에 의해 조절되는 신호전달 전달체계와는 다른 경로로 미토콘드리아 생합성에 영향을 미칠 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.307-315
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• 2001

Litter size has been one of the important economic traits in porcine reproduction. The insulin-like growth factor (IGF) system has been shown to mediate actions of the steroid hormone or to synergize with other endocrine factors so that it consequently plays roles in reproductive processes, including ovulation, implantation, maintenance of pregnancy, and fetal development. However, the effect of the serum IGF system on porcine litter size has not been deeply studied. Therefore, this study was conducted to relate serum IFG-II concentration and IGF binding protein-3 (IGFBP-3) expression with porcine litter size. Moreover, the possible association of those with estrogen receptor (ER) as a candidate gene for litter size was investigated. Swine were separated into two groups showing high and low litter sizes, and sera were collected from sows in the estrous cycle to postnatal growth of their female progeny. Serum IFG-II concentration was measured by radioimmunoassay and IGFBP-3 expression was detected by Western ligand blotting. During the estrous cycle, IGFBP-3 expression in both groups decreased moderately from metestrus to estrus, but IFG-II concentration showed a reverse pattern. Also, IFG-II concentration and IGFBP-3 expression decreased gradually as pregnancy proceeded. Unlike IGFBP-3, IFG-II decreased moderately as newborn pigs grew. Significant differences in serum IFG-II amount between the two groups were detected at 60 (p<0.01), 75, 90, and 105 d (p<0.05) of pregnancy and at 60 (p<0.01), 45, and 105 d (p<0.05) of postnatal growth. Furthermore, based on ER genotypes, a high litter size group with genotypes AB and BB showed lower IFG-II concentration than a low litter size group with a genotype AA during pregnancy. Taken together, the results indicate that the serum IFG-II and IGFBP-3 are correlated with the litter size in pigs.

• 한방비만학회지
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• 제13권2호
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• pp.74-83
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• 2013

Objectives: This study was performed to evaluate the effects of fermented lotus extracts on the inhibition of differentiation in 3T3-L1 preadipocytes. Methods: Extracts of lotus leaf and lotus root were fermented using 4 different probiotics separately, including Lactobacillus plantarum, Lactobacillus rhamnosus, Bifidobacterium breve, and Bifidobacterium longum. Inhibition of preadipocyte differentiation was examined by Oil red O dye staining. Expressions of adipogenic transcription factors including CCAAT/enhancer binding proteins (C/$EBP{\alpha}$) and peroxisome proliferators-activated receptor ${\gamma}$ ($PPAR{\gamma}$) were analyzed by real time polymerase chain reaction and Western blotting analysis. Results: Fermented lotus extracts inhibited adipogenic transcription factors by inhibiting preadipocytes differentiation. All of the groups fermented by 4 kinds of probiotics showed reduction in Oil Red O dye staining. Bifidobacterium breve showed the most effective inhibition of C/$EBP{\alpha}$. Bifidobacterium breve and Bifidobacterium longum showed the best downregulation of $PPAR{\gamma}$ expressions compared with the control and the unfermented lotus group. Conclusions: Fermented lotus extracts showed significant effects on inhibition of preadipocyte differentiation in 3T3-L1 preadipocytes showing correlation with insulin sensitivity and lipid metabolism related with obesity.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제21권2호
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• pp.111-117
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• 2018

Purpose: The prevalence of obesity has significantly increased among children and adolescents worldwide and is becoming an important health care problem in parallel with the increased prevalence of obesity pediatric non-alcoholic fatty liver disease. Betatrophin is a newly define hormone that is commonly secreted by liver and plays role in glucose tolerance. This study aimed to investigate the relationship between serum betatrophin levels and non-alcoholic fatty liver disease in obese children. Methods: The study included 40 obese children with a body mass index (BMI) above 95th centile, and 35 non-obese subjects with a BMI 3-85th centile, whose age and gender were similar to those of the patient group. For the evaluation of metabolic parameters fasting serum glucose, insulin, alanine aminotransferase, aspartate aminotransferase, lipid profile and serum betatrophin levels were measured. Total cholesterol: high-density lipoprotein cholesterol and low-density lipoprotein cholesterol: high-density lipoprotein cholesterol ratios were calculated as "atherogenic indices." Results: Serum betatrophin levels of the obese subjects were similar to that of non-obese subjects (p=0.90). Betatrophin levels were not correlated with the metabolic parameters. Conclusion: In the present study, levels of betatrophin are not different between obese and insulin resistant children and non-obese subjects, and they are not correlated with atherogenic indices. To elucidate the exact role of betatrophin in obesity, further studies are required to identify the betatrophin receptor and/or other possible cofactors.

• Nutrition Research and Practice
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• 제9권6호
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• pp.628-636
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• 2015

BACKGROUND/OBJECTIVES: Obesity is a risk factor of breast cancer in postmenopausal women. Estrogen deprivation has been suggested to cause alteration of lipid metabolism thereby creating a cellular microenvironment favoring tumor growth. The aim of this study is to investigate the effects of estrogen depletion in combination with excess energy supply on breast tumor development. MATERIALS/METHODS: Ovariectomized (OVX) or sham-operated C3H/HeN mice at 4 wks were provided with either a normal diet or a high-fat diet (HD) for 16 weeks. Breast tumors were induced by administration of 7,12-dimethylbenz(a)anthracene once a week for six consecutive weeks. RESULTS: Study results showed higher serum concentrations of free fatty acids and insulin in the OVX+HD group compared to other groups. The average tumor volume was significantly larger in OVX+HD animals than in other groups. Expressions of mammary tumor insulin receptor and mammalian target of rapamycin proteins as well as the ratio of pAKT/AKT were significantly increased, while pAMPK/AMPK was decreased in OVX+HD animals compared to the sham-operated groups. Higher relative expression of liver fatty acid synthase mRNA was observed in OVX+HD mice compared with other groups. CONCLUSIONS: These results suggest that excess energy supply affects the accelerated mammary tumor growth in estrogen deprived mice.