• 대한수의학회지
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• 제40권3호
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• pp.489-496
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• 2000

본 연구에서는 Streptozotocin-induced 당뇨가 혈청과 간장 및 신장조직의 IGF-I, IGFBPs 및 IGF-I carrier protein 특성에 미치는 영향을 조사하였다. 혈액과 조직중의 IGF-I 농도는 방사면역측정법으로 측정하였고, IGFBPs 양상은 Western Ligand Blotting(WLB)으로 관찰하였으며, IGF-I carrier protein의 특성은 column chromatography로 측정하였다. 혈청과 IGF-I 농도는 당뇨군이 대조군에 비하여 유의하게 감소하였다 (p<0.01). 당뇨군은 대조군에 비하여 간장 IGF-I 농도는 유의하게 감소한 반면, 신장의 IGF-I 농도는 유의하게 증가하였다(p<0.01). 당뇨군은 대조군에 비하여 혈청과 간장의 IGFBP-3는 감소한 반면, IGFBP-2는 증가하였고, IGFBP-4는 변화가 없었다. 또한 당뇨군은 대조군에 비하여 150kDa carrier protein은 감소하였으며, 50kDa carrier protein은 증가하였다. 이상의 결과를 종합해볼 때 Streptozotocin-induced 당뇨는 혈청 뿐만 아니라 조직의 IGF-I/IGFBP system 변동에 영향을 미침을 알 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10085-10089
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• 2015

Background: The insulin-like growth factor (IGF) system comprises a group of proteins that play key roles in regulating cell growth, differentiation, and apoptosis in a variety of cellular systems. The aim of this study was to investigate the role of insulin-like growth factor binding protein 3 (IGFBP3) in hepatocellular carcinoma. Materials and Methods: Expression of IGF2, IGFBP3, and PTEN was analyzed by qRT-PCR. Lentivirus vectors were used to overexpress IGFBP3 in hepatocellular carcinoma cell (HCC) lines. The effect of IGFBP3 on proliferation was investigated by MTT and colony formation assays. Results: Expression of IGF2, IGFBP3, and PTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2'-deoxycytidine/trichostatin A treatment, significant demethylation of the promoter region of IGFBP3 was observed in HCC cells. Overexpression of IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells. Conclusions: Expression of IGF2, IGFBP3, and PTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2'-deoxycytidine/trichostatin A treatment, significant demethylation of the promoter region of IGFBP3 was observed in HCC cells. Overexpression of IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1508-1513
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• 2006

Myostatin (MSTN) and insulin-like growth factors (IGFs) are a known inhibitor and stimulators of proliferation and differentiation of muscle cells, respectively. The present study was performed to investigate the relationship of MSTN-induced growth inhibition to expression of the IGF system components and myogenin, a muscle cell-specific transcription factor, in rat L6 myoblasts. The L6 cells transfected with a green fluorescent protein-MSTN plasmid expression construct had a 47% less cell number than mock-transfected cells after 3-d serum-free culture, accompanied by delayed differentiation which was suggested by inhibited aggregation of cells. Moreover, cells transfected with the expression construct had decreased expression of IGF-II and myogenin genes, but not IGF-I or its receptor genes, as examined by reverse transcription-polymerase chain reaction. The reduced mitosis of the L6 cells transfected with the MSTN-expression construct increased following an addition of either IGF-I or IGF-II to the culture medium, but not to the level of mock-transfected cells. By contrast, myogenin gene expression in these cells increased after the addition of either IGF to the level of mock-transfected cells. Collectively, these results suggest that the inhibitory effect of MSTN on L6 cell proliferation and differentiation is likely to be partly mediated by serially suppressed expression of IGF-II and myogenin genes, not IGF-I gene.

• BMB Reports
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• 제38권2호
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• pp.225-231
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• 2005

Acid-labile subunit (ALS) is a component of the 150-kDa insulin-like growth factor-binding protein-3 (IGFBP-3) complex, which, by sequestering the majority of IGFs-I and -II and thereby prolonging the half-life of them in plasma, serves as a circulating reservoir of IGFs in mammalian species. A pGEX-2T plasmid and a baculovirus expression constructs harboring a coding sequence for glutathione-S transferase (GST)-porcine ALS (pALS) fusion protein were expressed in BL21(DE3) E. coli and Sf9 insect cells, respectively. The expressed protein was purified by glutathione or Ni-NTN affinity chromatography, followed by cleavage of the fusion protein using Factor Xa. In addition, pALS and hIGFBP-3 were also produced in small amounts in the Xenopus oocyte expression system which does not require any purification procedure. A 65-kDa pALS polypeptide was obtained following the prokaryotic expression and the enzymatic digestion, but biochemical characterization of this polypeptide was precluded because of an extremely low expression efficiency. The baculovirus-as well as Xenopus-expressed pALS exhibited the expected molecular mass of 85 kDa which was reduced into 75 and 65 kDa following deglycosylation of Asn-linked carbohydrates by Endo-F glycosidase, indicating that the expressed pALS was properly glycosylated. Moreover, irrespective of the source of pALS, the recombinant pALS and hIGFBP-3 formed a 130-kDa binary complex which could be immunoprecipitated by anti-hIGFBP-3 antibodies. Collectively, results indicate that an authentic pALS protein can be produced by the current expression systems.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.99-99
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• 2001

The acid-labile subunit (ALS) associates with insulin-like growth factor (IGF)-I or -II and IGF binding protein-3 (IGFBP-3) to form a 150-kD complex in the circulation. This complex is thought to regulate the serum IGFs by restricting them in the vascular system and promotes their endocrine actions. Little is known about how ALS binds to IGFBP3, which connects the IGFs to ALS. Xenopus oocyte was utilized to study the function of ALS in assembling IGFs into the ternary complexes. Xenopus oocyte was shown to correctly translate in vitro transcribed mRNAs of ALS and IGFBP3. IGFBP3 and ALS mRNAs were injected in mixture and their products were immunoprecipitated by antisera against ALS and IGFBP3. Contrary to the traditional reports that ALS interacts only with IGF-bound IGFBP3, this study shows that ALS is capable of forming a binary complex with IGFBP3 in the absence of IGF. When cross-linked by disuccinimidyl substrate, band representing ALS-IGFBP3 complex was evident on the PAGE. IGFBP3 movement was monitored according to the distribution between the hemispheres. Following a localized translation in the vegetal hemisphere, IGFBP3 was shown to remain in the vegetal half in the presence of ALS. Different from wild type IGFBP3, however, mutant IGFBP3 freely diffused into the animal half despite the presence of ALS. Taken together, this study suggests that ALS may play an important role in sequestering IGFBP3 polypeptides via the intermolecular aggregation. Studies using this heterologous model will lead to a better understanding of the IGFBP3 and ALS assembling into the ternary structure and circulating IGF system.

• Asian-Australasian Journal of Animal Sciences
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• 제23권12호
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• pp.1668-1676
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• 2010

The somatotropic axis plays a key role in proliferation and differentiation of avian organs during both pre- and posthatching periods. This review discusses the complexity of regulation of the endocrine system for chicken development and growth by growth hormone (GH), insulin-like growth factor (IGF), and IGF binding protein (IGFBP). In addition, the thyrotropic axis, including thyrotropin-releasing hormone (TRH) and thyroid hormones ($T_4$ and $T_3$), is also involved in the GH-secreting pattern. In mammals, IGFI and -II are always sequestered in a 150 kDa non-covalent ternary complex. This complex consists of one molecule each of IGF-I or IGF-II, IGFBP-3 or IGFBP-5 and an acid labile subunit (ALS). Chick ALS is identified in different strains for the first time, and further investigation of the expression of ALS on developmental stage and ALS effect on IGF bioavailability may be addressed in the future.

• Clinical and Experimental Reproductive Medicine
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• 제23권3호
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• pp.247-268
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• 1996

여포와 난포의 성숙, 배란과 착상, 임신의 유지와 태아의 성장 발달, 분만 및 유선발육과 비유 등 일련의 생식현상에서 있어서 성선자극호르몬과 스테로이드 호르몬의 작용이 중추적인 역할을 한다는 사실은 오래 전부터 알려져왔다. 그러나 이러한 일련의 현상에 고전적인 호르몬 외에도 다수의 성장인자가 관여되고 있음이 최근의 연구 결과 밝혀지고 있다. 생식기관에서 성장인자들은 대부분 autocrine/paracrine mode로 작용하여, 성선자극호르몬과 스테로이드 호르몬의 작용을 매개하거나 이들 호르몬 등과 교호적인 작용(synergy)을 한다. 생식기관 내 insulin-like growth factor(IGF) system은 최근 가장 활발히 연구된 분야 중의 하나로 생식현상의 전반에 걸쳐 중요한 역할을 하고 있음이 밝혀졌다. 본 지면에서는 IGF system에 관한 개괄적인 정보를 소개하고 현재까지 보고된 intrauterine IGF system에 관한 연구를 요약하고자 한다. IGF family는 IGF-I과 IGF-II ligands, 두종류의 IGF receptors(수용체), 그리고 지금까지 발견된 6종류의 IGF-binding proteins(IGFBPs)로 이루어져 있다. IGF-I과 IGF-II는 proinsulin과 상동한 구조를 가진 peptide로서 포도당과 아미노산 운반을 자극하는 등 insulin과 유사한 작용을 한다. 이 외에도 IGFs는 세포분열촉진제(mitogens)로서 여러 형태의 세포에 걸쳐 세포증식을 자극하고, 세포의 분화(differentiation)과 세포기능의 발현에 관여한다. IGFs는 간과 주로 messenchymal cells에서 발현되어 endocrine mode는 물론 autocrine/paracrine mode로 거의 모든 조직에 작용한다. IGF 수용체는 두종류가 알려져 있는데 type I IGF receptor는 tyrosine kinase로서 IGF-I과 IGF-II에 공히 high-affinity를 나타내고, 상기한 대부분의 IGFs의 작용을 매개한다. Type II IGF receptor 혹은 IGF-II/mannose-6-phosphate receptor는 두개의 서로 다른 binding sites를 가지고 있는데 IGF-II binding site는 IGF-II에만 high-affinity를 나타낸다. Type II IGF receptor의 주요 역할은 IGF-II를 lysosomal targeting하여 ligand를 파괴하는데 있다. 체액 속의 IGFs는 대부분 IGFBP에 결합되어 있다. IGFBPs는 IGF의 저장/운반체 혹은 IGF 작용을 조절하는 역할을 하는 것으로 알려져 있으나 개개 IGFBP의 역할에 대해서는 지극히 제한된 정보만이 알려져 있다. IGFBPs의 IGF ligands에의 affinity는 IGF receptors의 IGFs에의 affinity보다 크기 때문에 대부분의 in vitro 상황 하에서 IGFBPs는 IGF 작용을 억제한다. IGFBP에 결합되어 있는 IGF가 어떤 기작에 의해 IGFBP로부터 분리되어 IGF receptor에 도달하는지는 알려지지 않고 있으나, 혈액과 조직액에 들어있는 불특정 IGFBP protease activity는 IGF의 방출과정에서 일역을 하는 것으로 믿어지고 있다. 최근 연구보고에 의하면 특정 in vitro 상황 하에서 IGFBP-1, -3, -5 등은 IGF와 무관한 작용도 있다는 증빙이 있어 IGF system의 또 다른 차원을 예고하고 있다. IGF family members의 mRNAs & proteins는 영장류, 설치류 및 가축의 자궁조직과 수태물(conceptus)에서 발현되어 자궁과 태아의 성장 발달에 중요한 역할을 한다. 자궁조직의 IGF system의 발현은 성선호르몬, 국소 생리조절인자 등에 의해 발현시기와 장소의 특이성이 결정되며, 발현된 IGFs와 IGFBPs는 autocrine/paracrine mode로 자궁조직에 작용하기도 하고, 자궁강에 분비되어 수태물의 성장 발달에 관여한다. 착상을 전후하여 수태물에서도 IGF system이 발현되는데 개개 IGF family member의 발현 시기는 모체로부터 유래된 mRNA의 유무, 수태물 자체의 genetic programming, 모체와의 상호작용 등에 의해 결정되고, IGFs의 작용 부위 역시 시간(생리적 상태)과 장소의 특이성이 있다. 이와같이 conceptus IGF system의 발현이 시간적, 공간적으로 조절되고있다는 사실은 IGFs가 수태물의 성장 발달에 일역을 한다는 가설을 간접적으로 지지해 준다. 자궁조직과 수태물에서 발현된 IGFs는 세포의 증식과 분화, 포도당과 아미노산의 운반과 단백질합성, placental lactogen과 prolactin 등과 같은 유선자극호르몬의 생성을 자극하고 스테로이드 호르몬의 합성에도 관여한다. 태아의 성장 발달에 있어서 IGFs의 역할은 embryo의 IGF-I, IGF-II, 혹은 IGF receptor gene을 homologous recombination technique에 의해 파괴(gene targeting)하여을 때의 결과로써 입증되었다. 생쥐의 IGF and/or IGF-II gene 혹은 IGF receptor gene을 파괴했을 때 출생 전후 모두 성장 발달이 지연되며 출생시 무게는 정상치의 30-60% 수준에 머물고, 특히 type I IGF receptor gene 혹은 IGF-I과 IGF-II genes를 모두 파괴했을 경우에는 출생 후 곧 치사한다. 자궁 내의 IGFBPs는 IGF ligands를 자궁 내에 제한시키거나 IGFs의 receptor binding을 억제하는 negative regulators 역할을 하는 것으로 믿어지고 있다. 그러나 영장류의 자궁에서 IGFBP-I과 같은 특정 IGFBP는 IGFs보다 월등히 많은 양이 발현 분비되고 있는 것으로 추산되고 있으며, 또한 이 단백질은 모체탈락막세포에서 분비되는 주요 단백질 중의 하나라는 점을 감안할 때 IGFBP-I이 IGF과 무관한 작용이 있을 가능성도 배제할 수 없다. 따라서 IGFBPs의 역할 규명은 IGF system을 이해하는데 중요한 부분을 차지하고 있어 향후 이 분야의 연구에 많은 기대와 촛점이 모여지고 있다.

• 대한수의학회지
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• 제43권3호
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• pp.383-392
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• 2003

Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are important regulators on the development of maternal tissues during pregnancy. This study was performed to examine the relationship between maternal IGFs/IGFBPs system (i.e: IGF-I, II, their receptors, and IGFBPs) in pre- and post-partum rats. The liver and kidney are important organs for the synthesis of IGFs and IGFBPs in adults. The levels of materanal IGFs and IGFBPs in serum, liver, and kidney were examined at 14 and 21 days of gestation and at 3, 7, 11, and 14 days after birth. The expression of IGFs and their receptors mRNA was also examined in fetal and maternal rat liver, kidney. IGF-I concentrations in maternal serum and liver were decreased during pregnancy. However, IGF-I concentration in maternal kidney was increased, having maximal effect at 14 days of gestation. IGF-I concentrations were decreased in serum, liver, and kidney of postpartum rat, compared to control (p < 0.05). On the other hand, IGF-II concentrations in serum, liver, and kidney were increased during pregnancy (p<0.05) and gradually decreased to control level in postpartum period. The levels of IGFBP-3 and IGFBP-2 are expressed in serum, liver, and kidney. However, IGFBP-3 is mainly expressed in serum and liver, and IGFBP-2 in kidney. The levels of IGFBP-3 and IGFBP-2 in maternal serum were markedly decreased during pregnancy and gradually recovered to control level during postpartum period by western ligand blotting. However, there was no change of IGFBP-3 and IGFBP-2 levels by western immunoblotting. The levels of IGFBP-3 and IGFBP-2 in maternal liver and kidney also showed the same pattern of serum, although the main IGFBP is different. In normal rat serum, IGF-I 150 kDa and 50 kDa carrier proteins were detected. The level of IGF-I 150 kDa carrier proteins in pregnant rat was decreased compared to normal rat, but that of 50 kDa carrier proteins was increased. IGFBP-3 protease activity was identified in pregnant rat serum and maternal placenta, and it was inhibited by EDTA ($Ca^{2+}$ chelating agent) and aprotinin (serine proteinase inhibitor). Taken together, these results suggest that the changes of IGFs and IGFBPs in maternal rats are regulated by liver and kidney IGFs and their receptors mRNA during the pregnancy.

• 한국수산과학회지
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• 제45권5호
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• pp.423-429
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• 2012

This study evaluated the effects of adding sea mustard Undaria pinnatifida glycoprotein to the diet of juvenile olive flounder Paralichthys olivaceus on its growth, and levels of insulin-like growth factor I (IGF-I), IGF binding proteins (IGFBPs), and interleukins. Three experimental diets (U0, U0.5, and U1.0) were formulated that contained different amounts of an extract of U. pinnatifida (0, 0.5, and 1.0%, respectively). Experimental groups were established in triplicate (30 fish/group) and fed for 12 weeks. The experimental group fed 1.0% added U. pinnatifida glycoprotein had the greatest rate of weight gain, which differed significantly from the other experimental groups. SDS-PAGE of the plasma IGF-I and muscle protein showed that the experimental groups taking U. pinnatifida glycoprotein had significantly more IGF-I and a ca. 200 kDa protein, as compared to the control group. In addition, the amount of IGFBP-3 at ca. 43 kDa increased in the group given the U. pinnatifida extract, as compared to the control group. The interluekin-2, -4, -6, and -12 levels paralleled the level of growth factor in the groups given the U. pinnatifida extract. In conclusion, supplementing the diet of olive flounder with U. pinnatifida glycroprotein improved its growth and immunity.

• 수산해양기술연구
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• 제59권4호
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• pp.387-398
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• 2023

Conventional aquaculture faces declining productivity, shifting to recirculating aquaculture system (RAS), known for minimizing water usage and maintaining consistent water temperatures for year-round fish growth. Rainbow trout (Oncorhynchus mykiss), a globally important cold-water species and the third most farmed fish in inland waters of Korea, valued for its fecundity and rapid growth. Dissolved oxygen, an important environmental factor affecting fish production and economics, highlights the need for smart aquaculture practices. Since 2018, the rise of intelligent aquaculture platforms, incorporating information and communications technology (ICT), emphasizes the essential role of RAS implementation. This eight-week study aimed to determine the optimal dissolved oxygen concentration for rainbow trout in RAS, utilizing a device for continuous monitoring, control and record. Dissolved oxygen concentrations were set at 5-6 mg/L, 9-10 mg/L, 14-15 mg/L and 17-18 mg/L. The growth rate significantly decreased at 5-6 mg/L, with no significant differences in other experimental groups. In hematological analysis, growth hormone (GH) was significantly highest at 5-6 mg/L, followed by 9-10 mg/L while Insulin-like growth factor-1 (IGF-1) was significantly lowest at 5-6 mg/L. In conclusion, the optimal dissolved oxygen concentration for rainbow trout in RAS is approximately 9-10 mg/L. Higher concentrations do not contribute to further growth or profitability.