• Asian-Australasian Journal of Animal Sciences
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• 제24권10호
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• pp.1393-1398
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• 2011

Four 4-month old Charolais${\times}$Dorset male sheep (initial liveweight $25.0{\pm}1.1\;kg$), fitted with rumen and abomasal fistulas and nourished by total intragastric infusions, were used to study the relationships between methionine (Met) supply, nitrogen (N) retention and plasma insulin-like growth factor-I (IGF-I). Four graded levels of Met, i.e. 0 g/16 g N, 1.76 g/16 g N, 3.52 g/16 g N and 7.04 g/16 g N, were infused into abomasums as experimental treatments. The sheep and treatments were allocated in a $4{\times}3$ incomplete Latin square design (Yudon square design). The experiment lasted 3 periods and each period was 10 days. Quadratic correlations were found between Met level (x, g/16 g N) and N retention (y, g/d): y = $-0.03x^2$+0.41x+2.62, $r^2$ = 0.66, n = 12, p = 0.008, and between methionine level (x, g/16 g N) and plasma IGF-I concentration (y, ng/ml): y = $0.80x^2$-4.53x+190.24, $r^2$ = 0.51, n = 12, p = 0.009. No significant correlation was found between plasma IGF-I (x, ng/ml) and N retention (y, g/d) (p>0.05). It was concluded that Met level had a significant influence on N retention and plasma IGF-I concentration whereas IGF-I might not be an important mediator in the regulation of N metabolism by Met in growing sheep nourished by total intragastric infusions.

• 한국수정란이식학회지
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• 제12권3호
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• pp.229-246
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• 1997

Implantation is a most important biological process during pregnancy whereby conceptus establishes its survival as well as maintenance of pregnancy. During the periimplantation period, both uterine endometriurn and conceptus synthesize and secrete a host of growth factors and cytokines which mediate the actions of estrogen and /or progesterone and also exert their steroid-independent actions. Growth factors expressed by the materno-conceptal unit en masse have important roles in cell migration, stimulation or inhibition of cell proliferation, cellular differentiation, maintenance of pregnancy and materno-conceptal communications in an autorcrine /paracrine manner. The present review focuses on the role of the intrauterine IGF system during periimplantation conceptus development. The IGF system comprises of IGF- I and IGF- II ligands, types I and II IGF receptors and six or more IGF-binding proteins(IGFBPs). IGFs and IGFBPs are expressed and secreted by uterine endometrium with tissue, pregnancy stage and species specificities under the influence of estrogen, progesterone and other growth factor(s). Conceptus also synthesizes components of the IGF system beginning from a period between 2-cell and blastocyst stages. Maternal IGFs are utilized by both maternal and conceptal tissues; conceptus-derived growth factors are believed to be taken up primarily by conceptus. IGFs enhance the development of both maternal and conceptal compartments in a wide range of biological processes. They stimulate proliferation and differentiation of endometrial cells and placental precursor cells including decidual transformation from stromal cells, placental formation and the synthesis of some steroid and protein hormones by differentiated endometrial cells or placenta. It is also well-documented in a number of experimental settings that both IGFs stimulate preimplantation embryo development. In slight contrast to these, prenatal mice carrying a null mutation of IGF and /or IGF receptor gene do not exhibit any apparent growth retardation until after implantation. Reason (s) for this discrepancy between the knock-out result and the in vitro ones, however, is not known. IGFBPs, in general, are believed to inhibit IGF action within the materno-conceptal unit, thereby allowing endometrial stromal cell differentiation as well as dampening ex cessive placental invasion into maternal tissue. There is evidence, however, indicating that IGFBP can enhance IGF action depending on environrnental conditions perhaps by directioning IGF ligand to the target cell. There is also a third possibility that certain IGFBPs and their proteolytic fragments may have their own biological activities independent of the IGF. In addition to IGFBPs, IGFBP proteases including those found within the uterine tissue or lumen are thought to enhance IGF bioavailability by degrading their substrates without affecting their bound ligand. In this regard, preliminary results in early pregnant pigs suggest that a partially characterized IGFBP protease activity in uterine luminal fluid enhances intrauterine IGF bioavailability during conceptus morphological development. In summary, a number of in vitro results indicate that IGFs stimulates the development of the rnaterno-conceptal unit during the periimplantation period. IGFBPs appear to inhibit IGF action by sequestering their ligands, whereas IGFBP proteases are thought to enhance intrauterine bioavailability of IGFs. Much is remaining to be clarified, however, regarding the roles of the individual IGF system components. These include in vivo evidence for the role of IGFs in early conceptus development, identification of IGF-regulated genes and their functions, specific roles for individual IGFBPs, identification and characterization of IGFBP proteases. The intrauterine IGF club house thus will be paying a lot of attention to forthcoming results in above and other areas, with its door wide-open!

• KSBB Journal
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• 제17권4호
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• pp.403-408
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• 2002

인체의 다양한 기능을 증진시키는 작용을 하는 것으로 알려진 IGF-I의 생체내 분비를 촉진시키기 위해 천연 생약재성분으로 구성된 YGF251을 개발하였고 YGF251의 효능을 측정하였다. 이중 맹검 시험 방식으로 40세에서 70세 사이의 성인 남녀 31명을 대상으로 IGF-I을 비롯하여 체중, 혈압, 간기능 검사 및 신장기능 검사를 실시하였다. YGF251 및 위약 투석 후의 IGF-I 함량변화에 대한 대응표본 검정결과는 YGF251 투여군에서 투여 전에는 245.6 ng/mL 이었는데 1개월 투여 후에는 269.3 ng/mL, 2개월 투여 후에는 275.6 ng/mL으로 유의하게 증가하였다 (p<0.05). 한편 위약 투여군에서는 투여 전에는 280.0 ng/mL이었으나 1개월 투여 후에는 239.2 ng/mL, 2개월 투여 후에는 230.2 ng/mL으로 유의하게 감소하는 결과를 보였다(p<0.05). 혈중 insulin함량은 실험군의 경우 YGF251 을 1개월 투여후 평균치로써 2배 정도의 증가를 보였으며 위약 투여군에서는 36% 정도 감소된 것으로 나타났다. 또한 YGF251투여에 의한 체중 및 혈압의 변화는 거의 나타나지 않았다. YGF251 투여에 의해 나타날수 있는 간기능 및 신장기능 변화를 관찰 하기 위해 여러 항목들의 수치는 측정 오차 범위내에서의 변화만을 나타내었다.

• 한국미생물·생명공학회지
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• 제42권2호
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• pp.139-144
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• 2014

신체가 성장한다는 것은 세포 수의 증가하면서 골격과 근육이 커지면서 그 기능이 강화된다는 것인데, 특히 키의 신장은 다리의 장골의 길이에 따라 크게 영향을 받으며, 이와같은 성장은 호르몬의 작용에 의해 이루어진다. 본 연구는 백하수오와 속단의 추출물의 섭취가 골격 성장과 성장호르몬의 분비 촉진에 관한 생물학적인 효과를 알아보고, 이러한 효과를 보다 높일 수 있는 백하수오 및 속단 추출물의 제조방법을 개발하고자 하였다. 백하수오 및 속단 추출물을 단회 투여하여 대표적인 혈중 성장호르몬 지표중의 하나인 IGF-I의 분비량 변화를 측정하였다. 8시간 경과시점을 기준으로 백하수오와 속단의 단순추출물을 섭취한 그룹은 대조군과 비교하여 IGF-I의 분비량을 각각 42%, 22% 증가하는데 그친 반면, ${\alpha}$-아밀라제를 처리한 추출물을 섭취한 그룹은 대조군과 비교하여 각각 63%, 36% 증가하는 결과를 얻었다. 이 결과로부터 백하수오와 속단의 추출물이 IGF-I의 분비를 촉진시켰음을 알 수 있으며, 추출물의 제조과정에서 ${\alpha}$-아밀라제를 처리한 백하수오와 속단 추출물이 더욱 효과가 뛰어남을 알 수 있었다. ${\alpha}$-아밀라제를 처리한 백하수오 및 속단 추출물을 8주 동안 섭취시킨 후, 실험군과 대조군의 장골의 길이를 비교 측정하였으며, 백하수오 및 속단 추출물을 섭취한 그룹의 장골길이는 대조군과 비교하여 각각 평균 6.4%, 5.8% 증가하였다. 이러한 결과로부터 백하수오와 속단의 추출물은 IGF-I 분비를 촉진하는 기능과 쥐의 뼈 골격 성장을 촉진하는 기능이 있음을 확인할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.297-304
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• 2006

Insulin-like growth factor-I (IGF-I) rich fraction, collected components between 1 kDa and 30 kDa, was fractionated from bovine colostral whey using an ultrafiltration membrane. IGF-I was confirmed in the collected IGF-I rich fraction by both SDS-PAGE and Western blotting. The concentration of IGF-I in the IGF-I rich fraction was 10 ng/mg protein. One hundred microliters of the reconstituted IGF-I rich fraction was intraperitoneally injected into ICR male mice for 2 weeks at 24 h intervals. The functions of peritoneal macrophages, including phagocytosis, interleukin (IL)-6 and tumor necrosis factor (TNF)-${\alpha}$ production, and nitric oxide and hydrogen peroxide production, were enhanced significantly by the administration of the IGF-I rich fraction in a dose-dependent manner (p<0.01). The proliferation of Concanavalin (Con) A-stimulated and Lipopolysaccharide (LPS)-stimulated splenocytes was also determined to have been enhanced significantly by the administration of the IGF-I rich fraction in a dose-dependent manner (p<0.01). Our results indicate that the administration of IGF-I rich fraction obtained from bovine colostral whey enhances both innate and acquired immunity for ICR male mice.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.113-118
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• 1999

The insulin-like growth factor (IGF) is found in all vertebrates and its type-II molecule is regarded as a fundamental embryonic growth factor during development. We have firstly identified, in this study, a cDNA clone corresponding to IGF-II (flIGF-II) from the adult brain of the teleost, Paralichthys olivaceus. We also examined the tissue expression of flIGF-II in several adult tissues by RT-PCR. The flIGF-II cDNA contained a complete ORF consisting of 215 amino acids and one stop codon. Its molecular characteristics appear to be similar to the previously identified IGF-II molecules, in which a common primary structure exhibiting B, C, A, D, and E domains is evidently observed. This cDNA clone seems to be cleaved at $Ala_{52}$ for the $NH_2$-end signal peptide and appears to produce a 98 amino acid-long E-peptide from the $Arg^{118}$. The functional B-D domain regions, therefore, include 65 amino acids and is able to encode a 7.4-kDa protein. The most prominent structural difference between IGF-I and IGF-II was that the D domain of IGF-II exhibits a two-codon-deleted pattern compared to the 8 amino acid-containing IGF-I. The insulin family signature in the A domain and six cysteins forming three disulfide bridges between the B and A domains were evolutionary-conserved from teleosts to mammalian IGF-II. Interestingly, the E-peptide region appears to provide a distinct hallmark between teleosts in amino acid composition. The flIGF-II shows 85.1% of sequence identity to salmon and trout, 90.6% to tilapia, and 98.4% to perch in amino acid level. In tissue expressions of IGF-II, it is very likely that flIGF-II has a significant expression in the adult brain. However, liver seems to be the main source for IGF-II production, and relatively low signals were observed in the adult muscle and kidney. Taken together, it would be concluded that the functional region for IGF-II mRNA is highly similar in phylogeny and is evolutionary, conserved as a mediator for the growth of vertebrates.

• 한국수산과학회지
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• 제33권6호
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• pp.541-545
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• 2000

알긴산은 3T3-L1 세포의 분화를 억제하였다. 3T3-L1 세포의 분화를 촉진시키는 인자로 밝혀진 IGF-I과 insulin을 이용하여 알긴산의 분화에 미치는 영향을 검토한 결과, 알긴산은 insulin의 분화촉진작용을 특이적으로 억제하였다. 본 연구는 알긴산을 이용하여 알긴산의 지질 감소효과를 세포의 수준에서 검증하고자 하였다는 점에서 그 의의가 있으며, 이에 알긴산의 분화억제효과가 일어나는 메카니즘에 관한 연구가 있어야 할 것으로 생각된다.

• 한국미생물·생명공학회지
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• 제43권2호
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• pp.175-175
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• 2015

• 대한치과교정학회지
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• 제35권5호
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• pp.351-360
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• 2005

이 연구는 $PGE_2$ 생합성 억제제인 인도메타신의 투여 시 성장기 개의 하악두 연골에 나타나는 cyclooxygenase-2 (GOX-2)와 insulin-like growth factor 1(IGF-1)의 발현과 분포를 관찰하여 인도메타신이 하악두 연골 성장에 미치는 영향을 규명하기 위하여 시행하였다 생후 12- 3주된 잡견 8마리를 4군으로 구분하였다 통상적 복용량인 인도메타신 2mg/Kg/day을 각각 7일과 14일간 투여한 군 과량인 8mg/Kg/day을 14일간 투여한 군과 무처치군인 대조군으로 구분하였으며. 하악두를 연구대상으로 하였다. 연구대상 하악두는 $5{\mu}m$ 두께의 절편을 만들어, H-E 중염색, COX-2 면역염색 IGF-1 면역염색을 시행하여 광학 현미경으로 검경하였으며, tartrate resistant acid phosphatase(TRAP) 염색 후 파연골세포의 수를 측정하여 다음과 같은 결과를 얻었다. 인도메타신은 하악두 연골의 증식대에서 COX-2와 IGF-1의 발현과 분포를 억제시켰으며, 인도메타신의 투여기간에 비례해서 파연골세포 수는 유의성 있게 감소하였다 (p<0.01) IGF-1의 발현과 분포는 인도메타신의 투여 양과 기간에 비례하여 억제되었다 이상의 결과에 의하면 인도메타신의 투여는 하악두 연골에서 COX-2와 IGF-1의 발현과 분포를 억제하고 파연골세포의 수를 감소시켜 하악두 성장을 억제할 가능성이 있음을 시사한다.

• Journal of Genetic Medicine
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• 제2권1호
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• pp.41-47
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• 1998

Human uniparental gestations such as gynogenetic ovarian teratomas provide a model to evaluate the integrity of parent-specific gene expression - i.e. imprinting - in the absence of a complementary parental genetic contribution. The few imprinted genes characterized so far include the insulin-like growth factor-2 gene (IGF2) coding for a fetal growth factor and H19 gene whose normal function is unknown but it is likely to act as an mRNA. IGF2 is expressed by the paternal allele and H19 by the maternal allele. This reciprocal expression is quite interesting because both H19 and IGF2 genes are located close to each other on chromosome 11p15.5. In situ RNA hybridization analysis has shown variable expression of the H19 and IGF2 alleles according to the tissue origin in 11 teratomas. Especially, Skin, derivative of ectoderm, is expressed conspicuously. We examined imprinting of H19 and IGF2 in teratomas using PCR and RT-PCR of exonic polymorphism. H19 and IGF2 transcript could be expressed either biallelically or monoallelically in the teratomas. Biallelic expression (i.e., loss of imprinting) of IGF2 occurred in 5 out of 6 mature teratomas and 1 out of 1 immature teratoma. Biallelic expression of H19 occurred in 4 out of 10 mature teratomas and 1 out of 1 immature teratoma. Expression levels of H19 and IGF2 transcript using the semi-quantitative RT-PCR had no relation between monoallelic and biallelic expression. Moreover, IGF2 biallelic expression did not affect allele-specificity or levels of H19 expression. These results demonstrate that both genes, H19 and IGF2, can be imprinted, expressed and regulated independently and individually of each other in ovarian teratoma.