• Molecules and Cells
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• 제28권5호
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• pp.495-499
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• 2009

Although insulin-like growth factor-I (IGF-I) and androgen receptor (AR) are well known effectors of skeletal muscle, the molecular mechanism by which signaling pathways integrating AR and IGF-I in skeletal muscle cells has not been previously examined. In this study, the role of PI3K/Akt on IGF-I-induced gene expression and activation of AR in skeletal muscle cells was investigated. C2C12 cells were treated with IGF-I in the absence or presence of inhibitors of PI3K/Akt pathway (LY294002 and Wortmannin). Inhibition of the PI3K/Akt pathway with LY294002 or Wortmannin led to a significant decrease in IGF-I-induced AR phosphorylation and total AR protein expression. Furthermore, IGF-I-induced AR mRNA and skeletal ${\alpha}-actin$ mRNA were blocked by LY294002 or Wortmannin. Confocal images showed that IGF-I-induced AR translocation from cytosol to nucleus was inhibited significantly in response to treatment with LY294002 or Wortmannin. The present results suggest that modulating effect of IGF-I on AR gene expression and activation in C2C12 mouse skeletal muscle cells is mediated at least in part by the PI3K/Akt pathway.

• 대한치과교정학회지
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• 제33권3호
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• pp.141-150
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• 2003

본 연구의 목적은 정상교합자의 전후방 및 수직적인 골격형을 군집분석을 이용하여 분류하고, 자연적인 치아치조부 보상기전으로 정상교합을 이룰 수 있는 골격의 범위와 한계를 파악하여 교정치료와 수술-교정 복합치료의 경계 증례에서 진단과 치료 계획 수립에 도움이 되고자 하는 것이다. 이를 위하여 대단위 구강 검진 중 15,836명으로부터 선발된 정상교합자 중 검사에 응한 294명의 측모 두부계측방사선사진의 투사도를 작성하여 계측하고, 인자분석을 통하여 18개의 골격계측항목 중에서 전후방적 골격 관계를 나타내는 인자와 수직적 골격 관계를 나타내는 인자를 추출하였으며, 이를 군집분석에 적용하여 정상교합자의 골격형을 9개의 군으로 분류할 수 있었다. 본문에서는 각 군의 전후방적, 수직적 골격계측 항목의 평균 및 표준편차를 구하고, 각 군 간의 차이를 비교 분석한 결과를 제시하고 있으며, 이를 통하여 정상교합자의 전후방적, 수직적 악골 관계가 매우 다양함을 알 수 있었다.

• 생명과학회지
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• 제27권8호
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• pp.879-887
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• 2017

히스톤 탈 아세틸 효소(HDAC)와 인슐린유사성장인자(IGF-I)는 근육 관련 유전자들의 활성 및 발현을 조절하여 골격근의 성장 및 발달을 조절하지만 이들이 근신경계 발달 및 대사 기능에 중요한 역할을 담당하는 뇌신경성장인자(BDNF)의 발현에 미치는 영향에 관한 연구는 거의 이루어지지 않았다. 따라서 본 연구에서는 IGF-I과 HDAC의 억제제인 SAHA가 C2C12 골격근 세포에서 BDNF 발현에 미치는 영향을 알아보고자 하였다. 그 결과 IGF-I은 농도와 시간 의존적으로 BDNF의 mRNA 및 단백질 발현을 감소시켰지만 HDAC을 억제하자 IGF-I에 의해 감소되었던 BDNF의 발현이 증가하는 경향을 관찰할 수 있었다. 따라서 IGF-I은 BDNF의 발현을 억제하며, HDAC의 억제는 IGF-I에 의한 BDNF의 발현 억제를 감소시킬 수 있다는 사실을 확인할 수 있었다.

• 생명과학회지
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• 제22권12호
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• pp.1651-1657
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• 2012

본 연구에서는 C2C12 근육 세포에서 IGF-I이 세포골격 연결 단백질인 plectin과 MACF1 유전자 발현에 미치는 영향에 대해 알아보았다. 그 결과 IGF-I이 plectin 유전자의 단백질과 mRNA 발현을 증가시켰으며, MACF1 mRNA 발현을 증가시켰음을 알 수 있었다. 이는 운동에 의해 근육에서 분비가 증가하는 IGF-I이 근육 관련 유전자들의 발현을 조절하여 근부피 유지에 영향을 미친다는 기존의 연구 결과들에서 더 나아가 골격근 구조 안정화 및 근수축 기전에 기여하는 plectin과 MACF1 유전자 발현에도 영향을 미친다는 사실을 증명하였다는데 의의가 있다고 사료된다. 향후 근수축 기전에 있어, 운동 형태, 근섬유의 종류에 따른 세포 골격 단백질의 역할 규명 및 조절자에 관한 연구가 더 수행된다면 운동이 골격근의 생리적 변화에 미치는 영향에 대한 추가적 정보를 제공할 수 있을 것이다.

• 대한치과교정학회지
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• 제49권3호
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• pp.170-180
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• 2019

Objective: The purpose of this study was to investigate the relationship between the facial skeletal patterns and the shape of the mandibular symphysis in adults with malocclusion by using a structural equation model (SEM). Methods: Ninety adults who had malocclusion and had records of facial skeletal measurements performed using cone-beam computed tomography were selected for this study. The skeletal measurements were classified into three groups (vertical, anteroposterior, and transverse). Cross-sectional images of the mandibular symphysis were analyzed using generalized Procrustes and principal component (PC) analyses. A SEM was constructed after the factors were extracted via factor analysis. Results: Two factors were extracted from the transverse, vertical, and anteroposterior skeletal measurements. Latent variables were extracted for each factor. PC1, PC2, and PC3 were selected to analyze the variations of the mandibular symphyseal shape. The SEM was constructed using the skeletal variables, PCs, and latent variables. The SEM showed that the vertical latent variable exerted the most influence on the mandibular symphyseal shape. Conclusions: The relationship between the skeletal pattern and the mandibular symphysis was analyzed using a SEM, which showed that the vertical facial skeletal pattern had the highest effect on the shape of the mandibular symphysis.

• PNF and Movement
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• 제6권2호
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• pp.51-57
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• 2008

Purpose : Mechanical stress activates signaling cascades and leading to a specific response of a network of signaling pathways. The purpose of this study is to review the effect of mechanical stress-induced adaptation in skeletal muscle involves a biological mechanisms. Methods : This is literature study with Pubmed, Medline and books. Results : Skeletal muscle tissue demonstrates a malleability and may adjust its metabilic response, vascularization and neuromuscular characteristic makeup in response to alteration in functional demands. The adaptation in skeletal muscle involoves a multitude of signalling mechanisms related with insuline-like growth factor, vascular endothelial growth factor, neurotrophins. Conclusions : The identification of the basic relationships underlying the malleability of skeletal muscle tissue is likely to be of relevance for our understanding with PNF technique.

• 대한치과교정학회지
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• 제15권2호
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• pp.249-259
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• 1985

To analyze the skeletal characteristics of the open bite, the faces of normal occlusion and open bite were measured using a cephalogram. The factors which were greatly different from normal occlusion were selected. The effects of these factors on the incisal overbite and correlation on these factors were studied. The following results were obtained: 1. The 13 factors which comprised the characteristics of the open bite were obtained. (Table 5) 2. The cause and amount of the open bite were dependent on the skeletal angulation than skeletal length. 3. For determining the incisal overbite, most highly correlated single factor was the interincisal angle. 4. The correlation on the selected 13 factors which comprised the characteristics of the open bite was obtained. (Table 6) 5. The open bite was due to combination of various factors than due to single factor. (Table 3,4).

• Molecules and Cells
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• 제28권3호
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• pp.189-194
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• 2009

The modulating effect of IGF-I on the regulation of AR gene expression and activation in skeletal muscle cells remains poorly understood. In this study, the effects of IGF-I treatment on AR induction and activation in the absence of AR ligands were examined. Differentiating C2C12 cells were treated with different concentrations (0-250 ng/ml) of IGF-I or for various periods of time (0-60 min) of 250 ng/ml IGF-I. Treatment of C2C12 cells with IGF-I resulted in a dose- and time-dependent increase in total AR and phosphorylated AR (Ser 213). IGF-I treatment also led to significantly increased AR mRNA expression when compared with the control. The levels of skeletal ${\alpha}-actin$ and myogenin mRNA, known target genes of AR, were also significantly upregulated after 5 or 10 min of treatment with IGF-I. Confocal images revealed that IGF-I stimulated nuclear localization of AR in the absence of ligands. In addition, an electrophoretic mobility shift assay indicated that IGF-I stimulated the AR DNA binding activity in a time-dependent manner. The present results suggest that IGF-I stimulates the expression and activation of AR by ligand-independent mechanism in differentiating C2C12 mouse skeletal muscle cells.

• 대한소아치과학회지
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• 제50권3호
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• pp.334-346
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• 2023

이 연구의 목적은 Skeletal maturity indicator (SMI) 및 Middle phalanx of the third finger (MP3)와 혈청 Insulin-like growth factor-1 (IGF-1) 및 Insulin-like growth factor binding protein-3 (IGFBP-3)의 상관 관계를 통해 골격적 성숙도의 예측 지표로 사용될 수 있는지 알아보는 것이다. 2018년 1월부터 2022년 12월까지 아주대학교 치과병원 및 소아청소년과에 내원한 만 7세 이상 17세 이하 환자 205명의 의무기록을 후향적으로 분석하였다. 혈청 IGF-1 농도는 SMI 6 - 8, MP3 - G에서 가장 높았고(p < 0.0001) 혈청 IGFBP-3 농도는 SMI 9 - 10, MP3 - I에서 가장 높았다(p = 0.010, 0.030). SMI, MP3와 혈청 IGF-1 농도 간 비교적 높은 Pearson 상관계수를 나타냈다(r = 0.698, 0.622, p < 0.0001). 혈청 IGF-1는 소아청소년의 골격적 성숙도를 평가하는 보조적 수단으로 활용될 수 있을 것이며 임상적으로는 472 ㎍/L에서 510.63 ㎍/L의 범위를 최대성장기로 고려할 수 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권9호
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• pp.1244-1249
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• 2002

Myostatin (growth differentiation factor (GDF)-8), is one member of the transforming growth factor $\beta$ superfamily. Investigations of GDF-8 null mice and double-muscled cattle revealed that GDF-8 has a profound influence upon skeletal muscle growth. Therefore, the GDF-8 effect upon the productive performance of pigs is worth exploring. In the present study, the nucleotide sequences and expression levels of GDF-8 genes in European pigs (Landrace and Duroc) and Asian pigs (Taoyuan and Small-ear) were evaluated. Based upon their genetic background these breeds possess significantly distinct growth rate and muscle productionphenotypes. Our sequence data showed that the nucleotide sequences of European and Asian pigs were 100% similar. Postnatal expression of GDF-8 gene in skeletal muscles, from birth to 12 mo of age, among different breeds was measured. GDF-8 expression levels in the longissimus muscle of neonatal European breed littermates were the highest, however it declined significantly (p<0.05) at 1 and 3 mo, and then increased gradually at 6 to 12 mo. The Asian breeds, however, GDF-8 expression level increased markedly at 3 mo and maintained a constant level thereafter. The results indicate that rather than polymorphism within the GDF-8 functional sequence between European and Asia breeds, it was relative to the gene regulation in postnatal muscle growth.