IGF-Ⅰ对培养兔关节软骨细胞作用的实验研究

目的 了解胰岛素样生长因子I（ICF－I）对培养关节软骨细胞增残及代谢的影响。方法 体外单层培养兔关节软骨细胞,实验组以10,100,200ng/mlICF-I作用细胞2,4,6天,对照组不加IGF－I作用培养细胞。检测细胞DNA及基质中糖醛酸含量,用流式细胞仪分析在100ng/mlIGF-I作用下细胞周期亚时相。结果 IGF－I在10－100mg/ml浓度范围内,对培养软骨细胞增残和代谢有促进作用,以100ng/ml浓度作用效果最佳,细胞周期分析,实验组DNA合成前期（G1期）较对照组缩短。结论 IGF－I促进软骨细胞的增殖与代谢,且通过缩短细胞G1期而缩短的细胞周期。     

EGF和IGF对体外培养兔关节软骨细胞的影响

目的　了解表皮生长因子 (EGF)和胰岛素样生长因子 (IGF)对体外培养兔关节软骨细胞存活数目和分裂增殖百分数的影响。方法　体外培养兔关节软骨细胞传至第 2代 ,分别以EGF、IGF ,以及二者不同的浓度组合作用于软骨细胞。通过酶联免疫检测仪 (MTT)测定软骨细胞存活数 ,流式细胞仪测定软骨细胞分裂增殖百分数。结果　不同浓度EGF对兔关节软骨细胞存活和分裂增殖均有促进作用 ,作用浓度强度次序为 :10ng/ml>0 1ng/ml>10 0ng/ml。不同浓度IGF对兔关节软骨细胞的存活和分裂增殖均有较强促进作用 ,浓度为 5 0ng/ml时 ,刺激效果最显著。EGF与IGF联合使用时 ,刺激效果优于任何一种因子单独使用 ,而以EGF 10ng/ml和IGF 5 0ng/ml为最佳浓度组合。 结论　EGF和IGF都可促进兔关节软骨细胞存活和分裂增殖 ,但以协同作用效果最佳。     

胰岛素样生长因子-Ⅰ对兔关节软骨细胞增殖及代谢的影响

目的　探讨胰岛素样生长因子 - (IGF- )对体外生长的关节软骨细胞分裂增殖及功能代谢的影响。方法　采用体外单层培养的方法 ,应用兔关节软骨细胞 ,对照组培养液为 10 %小牛血清 DMEM,实验组在培养液DMEM中加入 IGF- 使其终浓度分别为 3、10、30、10 0及 30 0 ng/ ml,作用细胞 2、4和 6天 ,检测细胞 DNA含量和基质中糖醛酸的含量。结果　 IGF- 在 3～ 30 0 ng/ ml浓度范围能明显增加培养软骨细胞的 DNA及糖醛酸的含量 ,且以30～ 10 0 ng/ ml作用 4天刺激效果最明显 ,与对照组相比 ,有统计学意义 (P<0 .0 1)。结论　 IGF- 对体外培养软骨细胞有刺激 ,并以剂量时间依赖性方式影响增殖及功能代谢。     

胰岛素样生长因子-1(IGF-1)对成骨细胞的成骨影响

目的：探讨不同浓度IGF－1对兔成骨细胞的成骨影响。方法：采用组织块细胞培养技术获得兔成骨细胞，第2代成骨细胞分别在含0.1ng/ml,1ng/ml,10ng/ml,20ng/mlIGF－1的DMEM中培养，24，36h后行MTT法检测细胞增殖情况，72，108h收集培养上清进行骨钙素放射免疫法（RI）测定。结果：IGF－1与成骨细胞培养24，36h，经MTT法检测，不同浓度IGF－1与对照组比较，有显著性差异（P＜0．001）；IGF－1浓度为0．1、1、10ng/ml，各组之间相比存在显著性差异（P＜0．05）；IGF－1与成骨细胞培养72．108h，经RI检测，不同浓度IGF－1对成骨细胞合成骨钙素与对照组比较无显著性差异（P＞0．05）：结论：IGF－1对成骨细胞有明显促进增殖作用，在0．1－10ng/ml范围，存在浓度依赖性，未发现IGF－1对成骨细胞合成骨钙素有影响。     

胰岛素样生长因子-1对成骨细胞生长影响的实验研究

目的:探讨胰岛素样生长因子-1对成骨细胞生长增殖的影响.方法:采用酶消化法获取兔骨膜成骨细胞,取第三代成骨细胞与0.1ng/ml、1ng/ml、10ng/ml的胰岛素样生长因子-1共同体外培养,在第1～7d观察细胞的形态、生长特点,MTT法测定细胞增殖情况,并通过细胞计数绘制细胞生长曲线.结果:不同浓度的胰岛素样生长因子-1对成骨细胞的生长增殖与对照组比较均有显著性差异(P＜0.01),各浓度之间对成骨细胞的生长增殖亦存在显著性差异(P＜0.05).结论:胰岛素样生长因子-1对成骨细胞生长增殖具有促进作用,在0.1～10ng/ml范围内此种作用与浓度呈正相关.     

胰岛素样生长因子对体外培养豚鼠肋软骨细胞的影响

目的：了解胰岛素样生长因子(insulin-1ike growthfactor-1，IGF-1)对体外培养豚鼠肋软骨细胞分裂增殖及功能代谢的影响。方法：体外单层培养豚鼠肋软骨细胞，对照组培养液为无血流清DMEM，实验组在培养液DMEM中加入IGF-1使其终浓度分别为10ng／ml、50ng／ml、100ng／ml，作用6天后，检测细胞DNA含量和培养液中糖醛酸的含量。结果：IGF-1在10～100ng／ml浓度范围能明显增加培养软骨细胞的DNA及糖醛酸的含量，且以50ng／ml作用效果最明显，与对照组相比，有统计擘意义(P＜0．01)。结论：IGF-1对体外培养肋软骨细胞有刺激，并以剂量依赖性方式影响细胞的增殖及功能代谢。     

胰岛素样生长因子-1对成骨细胞生长影响的实验研究

目的探讨胰岛素样生长因子-1对成骨细胞生长增殖的影响.方法采用酶消化法获取兔骨膜成骨细胞,取第三代成骨细胞与0.1ng/ml、1ng/ml、10ng/ml的胰岛素样生长因子-1共同体外培养,在第1～7d观察细胞的形态、生长特点,MTT法测定细胞增殖情况,并通过细胞计数绘制细胞生长曲线.结果不同浓度的胰岛素样生长因子-1对成骨细胞的生长增殖与对照组比较均有显著性差异(P＜0.01),各浓度之间对成骨细胞的生长增殖亦存在显著性差异(P＜0.05).结论胰岛素样生长因子-1对成骨细胞生长增殖具有促进作用,在0.1～10ng/ml范围内此种作用与浓度呈正相关.     

IGFl对兔关节软骨细胞增殖的影响及其形态学观察

目的 :了解胰岛素样生长因子1 (IGF1 )对体外生长的兔关节软骨细胞增殖以及细胞超微结构的影响。方法 :应用兔关节软骨细胞体外单层培养 ,对照组培养液为含 1 0 %小牛血清DMEM ,实验组在培养液DMEM中加入IGFl使其终浓度为 1 0 0 μg·L- 1 ,作用细胞 1周 ,得出细胞生长曲线 ,并分别测得两组DNA含量。同时观察IGFl 作用后 ,软骨细胞超微结构的变化。结果 :结果显示IGFl能明显促进培养软骨细胞增殖。实验组DNA含量 ,与对照组相比 ,有统计学意义 (P<0 .0 1 )。在电镜下 ,细胞主要表现为增殖性改变 ,说明细胞代谢活跃。结论 :IGFl 可刺激软骨细胞增殖 ,细胞超微结构表现代谢活跃状态     

胰岛素生长因子1在颅缝闭合中调节作用的实验研究

目的：研究胰岛素生长因子1对大鼠颅缝细胞的骨诱导作用和体外调节小鼠矢状缝闭合的作用。方法：获取新出生的SD大鼠的矢状缝细胞进行培养和出生8d的CD1小鼠矢状缝进行体外无血清器官培养基培养，加入胰岛素生长因子1（insulin lilce growth factor 1 IGF1），浓度分别为10ng/ml和40ng/ml，并设立不加IGF1者为对照组，应用RT－PCR检测颅缝细胞的成骨细胞表型碱性磷酸酶、骨钙素和骨桥蛋白mRNA表达，ELISA法检测培养液I型胶原的分泌，光镜观察小鼠矢状缝闭合的情况。结果：加入IGF1的矢状缝细胞的成骨细胞表型碱性磷酸酶、骨钙素和骨桥蛋白mRNA表达以及培养液I型胶原分泌量较对照组明显增高。有IGF1干预的矢状缝移植体培养8d时，颅缝内侧面骨板开始接近，培养20d时，颅缝小部分闭合，培养30d时颅缝大部分闭合，无IGF1干预的对照组培养30d，颅缝未发生闭合。结论：胰岛素生长因子1通过增强颅缝细胞的骨诱导促进颅缝的闭合。     

软骨生长因子对兔关节软骨缺损修复作用的实验研究

软骨生长因子(cartilage-derived growth factor，CDGF)是能促进软骨细胞生长，加速骨基质合成的类似于碱性成纤维细胞因子(bFGF)的碱性蛋白^[1]。在体外培养兔软骨细胞中，CDGF能以剂量依赖性的方式促进软骨细胞增殖和胶原的合成^[2]。然而生长因子若没有载体的保护，易被稀释或水解，最终失去生物学活性。我们以新西兰大白兔为实     

Growth hormone directly and indirectly stimulates articular chondrocyte cell growth

Although growth hormone (GH) is known to regulate cartilage growth and differentiation during development, it is still unclear whether the cell growth of articular chondrocytes is stimulated directly by GH or mediated by GH-induced insulin-like growth factor-I (IGF-I). In the present study, we focused on whether GH directly or indirectly stimulates articular chondrocyte proliferation. Monolayer articular chondrocytes from 5-week-old male Sprague-Dawley rats were cultured in Ham's F-12/Dulbecco's modified essential medium supplemented with 10% fetal bovine serum. Stimulation of DNA synthesis by GH was dose-dependent between 0.1 and 1 microg/ml, and the maximum active concentration of GH was 500 ng/ml, which induced a 3.5-fold increase over control values. Anti-IGF-I antiserum neutralized about 80% of GH-induced DNA synthesis. GH stimulated the secretion of IGF-I into the conditioned medium in a dose-responsive manner. To determine whether GH stimulated DNA synthesis directly, we investigated the time-course changes in mRNA expression of IGF-I and the proto-oncogene c-myc. Induction of IGF-I mRNA occurred at 4 h, and reached a maximum level at 12 h, whereas the expression of c-myc mRNA was induced within 4 h, and continued to increase until 72 h after GH treatment. Furthermore, administration of cycloheximide, an inhibitor of protein synthesis, resulted in the superinduction of both IGF-I and c-myc mRNAs. These results suggest that early induction of c-myc is due to a direct stimulatory effect of GH, and that long-term induction of c-myc was attributable to an indirect effect of GH in which GH-induced secondary proliferative factors may act in an autocrine/paracrine manner. The superinduction of c-myc gene by cycloheximide also indicates that fresh protein synthesis of an intermediate protein was not required for GH-induced c-myc expression. Western ligand blot analysis of IGF-binding proteins revealed that cultured rat articular chondrocytes produced a predominant 41 kDa and a faint 32 kDa form, and that GH significantly stimulated the secretion of the 41 kDa form without affecting expression of the 32 kDa form. Furthermore, a specific IGF-I binding study suggested that the increase in DNA synthesis induced by GH was not associated with changes in affinity or in the number of IGF-I binding sites. These results support the conclusion that the stimulatory effect of GH was mainly mediated by GH-induced IGF-I production in monolayer rat articular chondrocytes. However, it is likely that GH may also have a direct stimulatory effect by inducing c-myc proto-oncogene expression.     

Effect of basic fibroblast growth factor and hyaluronic acid on proliferation of rabbit chondrocytes in vitro

Objective: To investigate the effect of basic fibroblast growth factor (bFGF) and hyaluronic acid (HA) on the proliferation of rabbit chondrocytes in vitro. Methods: Chondrocytes from the knee joints of New Zealand white rabbits were cultured, bFGF or HA or both were added into the culture medium respectively, and the proliferation of the ehondrocytes was measured with MTT 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl-tetra-zolium bromide. (MTT, Sigma, M2128). Results: Basic fibroblast growth factor (10ng/ml) with low concentration of fetal bovine serum in the culture medium promoted the proliferation of chondrocytes significantly, and this effect reached its maximum when concentration of bFGF reached 50ng/ml. HA itself had no effect on the proliferation of chondrocytcs. However, when bFGF was used in combination with HA, especially when the concentration of bFGF was 50-500ng/ml and that of HA was 10-50ng/ml, the effect on the proliferation of chondrocytes was much more than when bFGF or HA was used alone. Conclusions: bFGF can promote the proliferation of chondrocytes. HA, which has no effect on the proliferation of the cells, can maintain a normal growth of chondrocytcs.When bFGF is used in combination with HA, more proliferation is obtained.     

Effects of IGF-I,IGF-II,and PDGF on the proliferation of rabbit articular chondrocytes in culture

The effects of insulin-like growth factor (IGF)-I, IGF-II, and platelet-derived growth factor (PDGF) were examined in cultured chondrocytes derived from rabbit joint cartilage. In addition, the expression of IGF-I receptors on the cultured chondrocytes was detected with anti-IGF-I receptor antibody. IGF-I acted as a growth stimulant, but IGF-II had no effect on cell growth. Increasing the dose of IGF-I beyond 50 ng/ml resulted in decreased growth stimulation. The expression of IGF-I receptors was detected continuously during the culture period. The results also showed that PDGF acted as a growth inhibitor, in contrast to the results of other studies. Further studies are necessary to clarify the precise mechanism of the action of PDGF and the role played by different homo- or heterodimers of PDGF in the proliferation of articular chondrocytes.     

In vitro cartilage regeneration from proliferated adult elastic chondrocytes

The purpose of this study was to investigate cellular feasibility in the proliferation and differentiation status of adult chondrocytes for cartilage regeneration in comparison to fetal chondrocytes. Primary cells were isolated from adult (n = 6) and fetal (n = 6) sheep ear cartilages and expanded in 10% fetal bovine serum (FBS) containing Ham's F12 medium, in which adult and fetal cell proliferation rates were compared using a WST-1 assay kit. Approximately 4 million cells were seeded onto each 1 x 1 x 0.2-cm (200 microL) nonwoven fabric scaffold made from polyglycolic acid. Cell/polymer constructs were cultured in serum-free DMEM/F12 medium supplemented with 5 ng/mL TGF-beta2 and 5 ng/mL des(1-3)IGF-I (adult chondrocytes, group A) or in 10% FBS containing Ham's F12 medium (adult chondrocytes, group B, and fetal chondrocytes, group C) as controls in a rotating bioreactor for 6 weeks. The proliferation assay showed that fetal cells had a significantly better growth potential than did adult cells. Histology and extracellular matrix analyses revealed that groups A and C qualitatively displayed better matrix deposition than did group B. In conclusion, although adult sheep elastic chondrocytes had less growth potential than did fetal cells, the serum-free medium supplemented with growth factors significantly enhanced the production of cartilage matrix secreted from proliferated adult sheep elastic chondrocytes.     

Serum-free culture of rabbit meniscal fibrochondrocytes: proliferative response

We have formulated a serum-free medium capable of supporting DNA synthesis in rabbit meniscal fibrochondrocytes at a level equivalent to 10% fetal bovine serum (FBS). The medium consists of a 1:1 mixture of Dulbecco's Modified Eagle's Medium and Ham's F-12 medium supplemented with transferrin (1 microgram/ml), selenium (1 pg/ml), trace metal mix (1:100), dexamethasone (100 ng/ml), insulin-like growth factors I and II (50 ng/ml each), pituitary fibroblast growth factor (100 ng/ml), and lactalbumin hydrolysate (2 micrograms/ml). Endothelial cell growth supplement could be substituted for lactalbumin hydrolysate to obtain similar results. Ventrex PC-1, a commercially available, low-protein, serum-free medium, was found to support proliferation of fibrochondrocytes but not as well as 10% FBS or our medium formulation. Lipid supplements, which are known to support the serum-free growth of hyaline chondrocytes, were found to be either of no value or antagonistic for the culture of fibrochondrocytes. Likewise, vitamin E alone, progesterone, putrescine, and hydrocortisone were also without benefit in our culture system. The cells had a more chondrocytic morphology when grown in defined medium as opposed to 10% FBS. The results of this study should now make it possible to identify and quantitate those factors necessary to affect meniscal repair by utilizing further techniques in vitro.     

bFGF对体外关节软骨细胞创伤愈合与增殖的影响

目的：探讨碱性成纤维细胞生长因子（ｂａｓｉｃ ｆｉｂｒｏｂｌａｓｔ ｇｒｏｗｔｈ ｆａｃｔｏｒ,ｂＦＧＦ）对关节软骨细胞创伤愈合与增殖行为的影响。方法;采用体外创伤愈合模型及ＭＴＴ比色方法,对软骨细胞创伤愈合与增殖行为进行分析。结果：ｂＦＧＦ浓度为５ｎｇ／ｍｌ时,即可显著促进软骨细胞创伤愈合,浓度为５０ｎｇ／ｍｌ时,其促进作用达到最大值。     

表皮生长因子对子宫内膜细胞体外增殖的影响

本研究观察了表皮生长因子（ＥＧＦ）在体外对子宫内膜上皮细胞及基质细胞增殖的影响。采用酶消化加物理方法分离人子宫内膜上皮细胞及基质细胞,分别在体外培养,细胞汇合后消化,一部分用盖片法培养,用特异性抗体鉴定细胞纯度,另一部分做细胞增殖实验。在细胞中加入不同浓度的ＥＧＦ,培养２４、４８、７２小时,用ＭＴＴ法及流式细胞仪测定ＥＧＦ对子宫内膜上皮细胞及基质细胞增殖的作用。结果：ＥＧＦ浓度为５．０及１０．０ｎｇ／ｍｌ时,明显刺激子宫内膜上皮细胞及基质细胞的增殖,ＭＴＴ与流式细胞仪两法一致。ＥＧＦ不刺激细胞凋亡。结论：采用酶消化结合物理方法分离的人子宫内膜基质细胞及上皮细胞,方法简便、快速,细胞纯度高,在体外生长良好,可用于体外研究着床及异位子宫内膜生长的机制。当ＥＧＦ浓度为５．０及１０．０ｎｇ／ｍｌ时,确实刺激子宫内膜细胞的增殖。     

Synergistic effects of FGF-2 with insulin or IGF-I on the proliferation of human auricular chondrocytes

Chondrocyte preparation with the safety and efficiency is the first step in cartilage regenerative medicine. To prepare a chondrocyte proliferation medium that does not contain fetal bovine serum (FBS) and that provides more than a 1000-fold increase in cell numbers within approximately 1 month, we attempted to use the medium containing 5% human serum (HS), but it exerted no more than twofold increase in 2 weeks. To compensate for the limited proliferation ability in HS, we investigated the combinational effects of 12 factors [i.e., fibroblast growth factor (FGF)-2, insulin-like growth factor (IGF)-I, insulin, bone morphogenetic protein-2, parathyroid hormone, growth hormone, dexamethasone, 1alpha25-dihydroxy vitamin D3, L-3,3',5'-triodothyronine, interleukine-1 receptor antagonist, 17beta-estradiol, and testosterone] on the proliferation of human auricular chondrocytes by analysis of variance in fractional factorial design. As a result, FGF-2, dexamethasone, insulin, and IGF-I possessed promotional effects on proliferation, while the combination of FGF-2 with insulin or IGF-I synergistically enhanced the proliferation. Actually, the chondrocytes increased 7.5-fold in number in 2 weeks in a medium containing 5% HS with 10 ng/ml FGF-2, while the cell number synergistically gained a 10-12-fold increase with 5 microg/ml insulin or 100 ng/ml IGF-I in the same period. The proliferation effects were more enhanced at a concentration of 100 ng/ml for FGF-2, and especially for the combination of 100 ng/ml FGF-2 and 5 microg/ml insulin (approximately 16-fold within 2 weeks). In the long-term culture with repeated passaging, this combination provided more than 10,000-fold within 8 weeks (i.e., passage 4). Thus, we concluded that such a combination of FGF-2 with insulin or IGF-I may be useful for promotion of auricular chondrocyte proliferation in a clinical application for cartilage regeneration.