壳聚糖改性聚醚醚酮表征及对MC3T3-E1细胞黏附、增殖的影响

背景：聚醚醚酮的生物惰性表面限制了其医学应用,如何提高聚醚醚酮的生物活性亟待解决。目的：分析壳聚糖生物活性涂层改性聚醚醚酮的表面特征及其对MC3T3-E1细胞增殖、黏附的影响。方法：取圆片状聚醚醚酮材料,依次进行NaBH4、3-氨丙基三乙氧基硅烷、戊二醛水溶液及壳聚糖溶液处理,获得壳聚糖生物活性涂层改性的聚醚醚酮材料。使用X射线光电子能谱、扫描电镜、原子力显微镜与全自动接触角测量仪观察化学处理前后聚醚醚酮材料的表面特征。将MC3T3-E1细胞分别接种于聚醚醚酮与壳聚糖改性聚醚醚酮材料表面,观察细胞的增殖与黏附情况。结果与结论：(1)X射线光电子能谱检测显示,聚醚醚酮材料仅含有C、O元素,壳聚糖改性聚醚醚酮材料含有C、O、N、Si元素;壳聚糖改性聚醚醚酮材料表面的接触角小于聚醚醚酮材料(P <0.05);(2)扫描电镜下可见,聚醚醚酮材料表面有明显的凹槽状起伏,壳聚糖改性聚醚醚酮材料表面存在壳聚糖分子,大小为1.0-2.0μm;原子力显微镜下可见,聚醚醚酮材料表面有较多的微小凹坑,大小约为0.1μm,壳聚糖改性聚醚醚酮材料表面的凹坑增大,大小为0.2-0.5μm,表面粗糙度大于聚醚...     

MC3T3-E1细胞与多组分纳米羟基磷灰石基三维复合支架材料的相容性

目的 观察MC3T3-E1细胞在复合支架材料上的黏附、增殖及形态,评价多组分纳米羟基磷灰石基三维复合支架材料的生物相容性.方法 采用仿生学方法,将壳聚糖、羟基磷灰石、明胶、果胶按照一定比例制作成多组分纳米羟基磷灰石基三维复合支架材料.在复合支架材料上接种MC3T3-E1细胞,通过倒置相差显微镜、HE染色、扫描电镜、四甲...     

壳聚糖-羧甲基壳聚糖复合膜的研制及其生物相容性评价

壳聚糖膜降解较慢^[1]，为了加快其降解速度，研制了壳聚糖-羧甲基壳聚糖复合膜(以下简称复合膜)并进行了生物学评价。结果表明，该复合膜具有很好的生物相容性，可以满足体内植入膜的基本要求。     

铅暴露对成骨细胞MC3T3-E1细胞线粒体的影响

目的评价铅暴露对成骨细胞MC3T3-E1线粒体的影响。方法在MC3T3-E1细胞培养瓶中加入不同浓度醋酸铅[Pb(Ac)2]溶液(0、1、10、100μmol/L)培养24 h后,分别测定其线粒体膜电位去极化程度与ATP合成量、胞浆与线粒体内细胞色素c含量以及Caspase-3活性,并利用透射电镜观察细胞线粒体形态变化。结果铅暴露可致成骨细胞MC3T3-E1线粒体膜电位降低,ATP合成减少,细胞内细胞色素c从线粒体到胞浆的释放增加,Caspase-3活性增强,并且呈明显剂量依赖关系。此外,电镜观察可见100μmol/L醋酸铅暴露组细胞线粒体明显肿胀。结论铅暴露可引起成骨细胞MC3T3-E1线粒体功能与结构损伤,从而导致细胞凋亡。     

纳米TiO2:C薄膜涂层的生物相容性评价

背景：前期实验采用溶胶-凝胶法在纯钛片表面制备了纳米TiO₂:C薄膜涂层。 目的：评估纳米TiO₂:C薄膜涂层的生物相容性。 方法：①溶血实验：取新西兰大白兔静脉血,分别加到TiO₂-生理盐水、TiO₂:C-生理盐水、蒸馏水和生理盐水中。②细胞毒性实验：将TiO₂:C浸提液加入对数生长期的L929 细胞培养基中。③短期全身毒性实验：将60只BALB/C小白鼠随机分为3组,分别灌胃给予TiO₂浸提液、TiO₂:C浸提液及生理盐水。④口腔黏膜刺激实验：将牙胶圆片与TiO₂:C纳米薄膜涂片分别缝合固定于仓地鼠颊黏膜上。 结果与结论：纳米TiO₂:C涂层未引起急性溶血,毒性等级为0-1 级,未对细胞产生明显毒性,细胞周期未见明显异常;TiO₂:C浸提液对小鼠无短期全身毒性;对仓鼠口腔黏膜无刺激性。表明纳米TiO₂:C薄膜涂层具有良好的生物安全性。     

高糖对成骨细胞MC3T3-E1凋亡和氧化应激的影响

目的评价高糖环境对成骨细胞MC3T3-E1凋亡和氧化应激的影响,为临床治疗糖尿病骨质疏松症提供实验基础。方法在细胞培养瓶中加入不同浓度高糖溶液(0、20、40、80 mmol/L)培养成骨细胞株MC3T3-E1,24 h后分别采用CCK-8测定其细胞存活率、细胞凋亡率,线粒体膜电位试剂盒测定其去极化程度,半胱天冬酶-3(Caspase-3)试剂盒检测其活性,DCFH-DA荧光探针检测ROS的生成。在80 mmol/L高糖环境暴露,MC3T3-E1细胞在抗氧化剂NAC作用下,采用上述方法测其线粒体膜电位和Caspase-3含量。结果与对照组相比,成骨细胞MC3T3-E1在高糖暴露下的存活率和线粒体膜电位下降,细胞凋亡率、细胞活性氧水平和Caspase-3活性增强,且都存在剂量依赖性;抗氧化剂NAC抑制高糖引起MC3T3-E1细胞线粒体膜电位降低和Caspase-3增高。结论高糖环境下,NAC通过抑制高糖引起的氧化应激,降低细胞凋亡率,保护成骨细胞MC3T3-E1。     

磁性壳聚糖微球的生物相容性

背景：采用壳聚糖对磁性氧化铁纳米颗粒表面进行改性,一方面可改善磁性纳米氧化铁颗粒的团聚性,增加其稳定性,另一方面将来可用于肿瘤热疗及基因治疗。 目的：制备将来可用于肿瘤热疗及基因治疗的磁性壳聚糖微球,评价其生物相容性。 方法：采用改良的化学沉淀法制备磁性氧化铁纳米颗粒。采用超声乳化法将壳聚糖加入到磁性氧化铁纳米颗粒中制备磁性壳聚糖微球,进行以下实验：①MTT实验检测磁性壳聚糖微球浸提液的细胞毒性：分别以1640培养液、聚丙烯酰胺单体溶液、100%,75%,50%,25%的磁性壳聚糖微球浸提液培养L-929细胞。②溶血实验：在兔抗凝血中分别加入磁性壳聚糖微球浸提液、生理盐水及蒸馏水。③微核实验：在昆明小鼠腹腔分别注射含氧化铁磁流体5,3.75,2.5,1.25 g/kg的磁性壳聚糖微球混悬液、环磷酰胺及生理盐水。 结果与结论：磁性壳聚糖微球粒径200-300 nm,分散效果有所提高。不同浓度的磁性壳聚糖微球浸提液对L-929 细胞毒性为1级,属对细胞无毒性范畴。磁性壳聚糖微球浸提液的溶血率为0.69%,小于5%,符合医用材料的溶血实验要求。磁性壳聚糖微球混悬液未导致细胞DNA断裂和非整倍体化,未导致微核产生的遗传毒理作用,材料无致畸或致突变作用,因此磁性壳聚糖微球具有良好的生物相容性。     

壳聚糖/纳米羟基磷灰石分层复合支架的生物相容性研究

制备壳聚糖/纳米羟基磷灰石(CS/nHA)分层复合支架,对其进行细胞毒性评价.分离培养大鼠软骨细胞接种于支架,相差显微镜和扫描电镜观察细胞的黏附及生长情况.动物皮下埋植试验观察其组织相容性.实验结果证实壳聚糖/纳米羟基磷灰石分层复合支架具有良好的生物相容性,有望成为较好的骨软骨组织工程支架.     

大鼠成骨细胞与壳聚糖/羟基磷灰石复合支架降解产物的生物相容性

背景：人们对壳聚糖/羟基磷灰石复合多孔生物支架在体内的降解过程并非十分清楚,而且有关其降解产物对成骨细胞的影响研究也较少。 目的：分析大鼠成骨细胞与壳聚糖/羟基磷灰石复合多孔生物支架降解产物的生物相容性。 方法：将培养的第2代大鼠成骨细胞分别在壳聚糖/羟基磷灰石复合支架降解产物浸提液和含体积分数10%胎牛血清的DMEM培养液中培养,培养第2,4,6,8,10天分别对两组细胞做MTT细胞计数,采用联合会推荐法测定细胞碱性磷酸酶活性,采用BCA蛋白定量法测定总蛋白。 结果与结论：在壳聚糖/羟基磷灰石复合多孔生物支架降解产物浸提液中培养的大鼠成骨细胞增殖速度、细胞碱性磷酸酶活性、细胞总蛋白合成及碱性磷酸酶与总蛋白的比值明显高于在体积分数为10%胎牛血清DMEM培养液中培养的细胞(P < 0.05)。表明壳聚糖/羟基磷灰石复合多孔生物支架的降解产物不仅可促进大鼠成骨细胞的黏附、生长和增殖,还可增强其骨化功能,具有较好的生物相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

Limonene attenuates methylglyoxal-induced dysfunction in MC3T3-E1 osteoblastic cells

Limonene is a common natural terpene with powerful antioxidative properties. This study investigated the effects of limonene, a terpene found in citrus fruits, on the function of the murine pre-osteoblast cell line, MC3T3-E1 cells. The results showed that limonene treatment significantly elevated collagen synthesis, alkaline phosphatase activity, osteocalcin synthesis, and mineralization in osteoblastic cells. Methylglyoxal (MG), a highly reactive dicarbonyl metabolite, is a major precursor of advanced glycation end products, which are involved in the pathogenesis of diabetic osteopathy. We therefore investigated the effects of limonene on MG-induced cytotoxicity. Pre-treatment of MC3T3-E1 cells with limonene prevented MG-induced cell death and apoptosis. Limonene also reduced MG-triggered endoplasmic reticulum (ER) stress, as indicated by decreases in the levels of the ER-localized transmembrane signal transducers ATF-6 and IRE1. Furthermore, limonene treatment significantly reduced MG-induced autophagic activity and reactive oxygen species release. These results suggest that limonene may prevent the development of diabetic osteopathy.     

反相高效液相色谱法测定壳聚糖纳米粒中丙酮酸乙酯的含量

背景：有关丙酮酸乙酯含量检测方法的研究较少,采用反相高效液相色谱法检测丙酮酸乙酯含量的文献更少。 目的：建立测定壳聚糖纳米粒中丙酮酸乙酯含量的反相高效液相色谱法。 方法：采用Agilent1200系列高效液相色谱仪检测丙酮酸乙酯-壳聚糖纳米粒中丙酮酸乙酯的含量。色谱柱：ZORBAX Eclipse XDB-C18(4.6 mm×150 mm,5 μm),柱温25 ℃,流动相为乙腈-水(体积比为40∶60),流速1 mL/min,检测波长210 nm,进样量20 μL。 结果与结论：丙酮酸乙酯峰与辅料及溶剂峰分离良好,丙酮酸乙酯质量浓度在1-100 mg/L内于峰面积线性关系良好(r =0.999 6),低、中、高浓度丙酮酸乙酯对照品溶液日内、日间精密度的相对标准偏差均小于3%,重复性实验的相对标准偏差为1.25%,稳定性实验的相对标准偏差为1.3%。3批样品的加样回收率分别为(91.5±1.0)%,(93.5±0.2)%,(94.4±0.4)%;包封率分别为(87.20±0.22)%,(90.50±0.15)%,(91.10±0.17)%。不同批次样品丙酮酸乙酯含量检测结果的相对标准偏差分别为0.9%,0.5%,0.3%。说明反相高效液相色谱法灵敏度高、线性范围宽、专属性强、精密度高、加样回收率好、结果精确可靠,可用于壳聚糖纳米粒中丙酮酸乙酯含量的测定。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

Abnormal Differentiation in MC3T3-E1 Preosteoblasts Expressing a Dominant-Negative Type I Collagen Mutation

To examine the effects that an organizing extracellular matrix might have on osteoblast precursors, we created MC3T3-E1 cell lines that stably incorporated a plasmid that expressed proαl(I) collagen chains having a truncated triple helical domain. Cells that had incorporated the proαl(I) expression plasmid (pMG155) efficiently secreted molecules with shortened prood(I) chains into culture media. Electron micrographs indicated that expression of the minigene dramatically interferes with normal type I collagen fibril architecture. The turnover of newly deposited collagenous matrix as measured by ³[H]-hydroxyproline release was 29% after a 14 day chase in cells expressing the mini-gene compared to essentially no turnover in control cultures. MC3T3-E1 cells in culture normally demonstrate a time dependent reduction of cell division followed by an increase in osteoblast characteristics. Cell number was consistently 20–25% higher than control in MC3T3-E1 cultures expressing the truncated prooαl(I) gene but ALP activity was only 45% of control. Secretion and steady state mRNA levels for osteocalcin were over fivefold higher than control cultures but expression of other extracellular matrix components was not changed. These findings demonstrate that osteoblasts require a normally structured collagenous matrix for inhibition of cellular proliferation and subsequent upregulation of ALP. However, in the presence of rapid turnover of osteoblast matrix, the gene for osteocalcin may be upregulated in response to local signals.     

流体剪切力通过下调p21促进 MC3T3-E1成骨细胞增殖

目的 探讨流体剪切力(fluid shear stress, FSS)对成骨细胞p21表达的影响,并明确p21在FSS诱导的成骨细胞增殖过程中的作用。方法 对成骨细胞加载不同时间(0、15、30、45、60 min)、1.2 Pa FSS。用CCK-8实验、EdU实验检测成骨细胞增殖活性。用siRNA p21或pcDNA p21转染成骨细胞,并用Western blotting检测转染效果。Western blotting检测不同干预条件下p21、cyclin D1、CDK4的表达变化。结果 加载1.2 Pa FSS后,p21表达显著下调,且加载45 min后表达水平最低。加载FSS和下调p21表达都显著增强成骨细胞增殖,并增加cyclin D1、CDK4表达。而上调p21表达后,加载FSS不再具有增强成骨细胞增殖和增加cyclin D1、CDK4表达的作用。结论 1.2 Pa FSS能够下调成骨细胞p21表达,在加载45 min时下调最为明显。p21下调对成骨细胞增殖具有促进作用,且FSS通过下调p21促进成骨细胞增殖。     

复合胰岛素样生长因子1壳聚糖胶原支架与人牙周膜细胞的增殖

背景：胰岛素样生长因子1具有促进成纤维细胞有丝分裂的作用,同时具有促进牙周细胞生长、分化及合成细胞外基质的作用。 目的：观察负载胰岛素样生长因子1的壳聚糖胶原支架对于人牙周膜细胞增殖的作用。 方法：将人牙周膜细胞分别接种于负载胰岛素样生长因子1的壳聚糖胶原支架与普通胶原支架上,于接种的1 h、24 h及1周检测重组人转化生长因子β1的释放,于第1,7,28天检测两组细胞的黏附和增殖情况。 结果与结论：负载胰岛素样生长因子1的壳聚糖胶原支架组第1,24小时和第1周的重组人转化生长因子β1释放率明显低于普通胶原支架组(P < 0.01)。两组接种第1天的细胞黏附和增殖检测比较差异无显著性意义  (P > 0.05),负载胰岛素样生长因子1的壳聚糖胶原支架组接种第7,28天的细胞黏附和增殖情况优于普通胶原支架组(P < 0.01)。表明负载胰岛素样生长因子1的壳聚糖胶原支架可显著促进人牙周膜细胞的增殖。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

Three-dimensional growth of differentiating MC3T3-E1 pre-osteoblasts on porous titanium scaffolds

The present work assesses the potential of three-dimensional porous titanium scaffolds produced by a novel powder metallurgy process for applications in bone engineering through in vitro experimentation. Mouse MC3T3-E1 pre-osteoblasts were used to investigate the proliferation (DNA content), differentiation (alkaline phosphatase activity and osteocalcin release) and mineralisation (calcium content) processes of cells on titanium scaffolds with average pore sizes ranging from 336 to 557 microm, using mirror-polished titanium as reference material. Scanning electron microscopy was employed to qualitatively corroborate the results. Cells proliferate on all materials before reaching a plateau at day 9, with proliferation rates being significantly higher on foams (ranging from 123 to 163 percent per day) than on the reference material (80% per day). Alkaline phosphatase activity is also significantly elevated on porous scaffolds following the proliferation stage. However, cells on polished titanium exhibit greater osteocalcin release toward the end of the differentiation process, resulting in earlier mineralisation of the extracellular matrix. Nevertheless, the calcium content is similar on all materials at the end of the experimental period. Average pore size of the porous structures does not have a major effect on cells as determined by the various analyses, affecting only the proliferation stage. Thus, the microstructured titanium scaffolds direct the behaviour of pre-osteoblasts toward a mature state capable of mineralising the extracellular matrix.     

Hydroxyapatite accelerates differentiation and suppresses growth of MC3T3-E1 osteoblasts

Hydroxyapatite describes both the natural mineral phase of bone as well as the widely used calcium-phosphate implant substitute. Given that hydroxyapatite is a major component of the in vivo surface with which osteoblasts interact, it is surprising that most studies examining the regulation of osteoblast growth and differentiation utilize plastic surfaces. Here we demonstrate that the phenotype of mouse MC3T3-E1 osteoblasts is significantly altered on hydroxyapatite compared with plastic surfaces. Specifically, alkaline phosphatase activity and messenger RNA levels, markers of early stages of osteoblast differentiation, are increased in osteoblasts cultured on hydroxyapatite. The precocious appearance of alkaline phosphatase activity on the hydroxyapatite surface suggests that osteoblast differentiation is activated earlier compared with plastic surfaces. Osteocalcin expression, a marker of late-stage differentiation, is also increased on hydroxyapatite and further demonstrates enhanced differentiation. Cell counts indicate that fewer osteoblasts are present on hydroxyapatite versus plastic surfaces 24 h after plating. Measurement of osteoblast attachment, apoptosis, and necrosis indicated no differences between surfaces. In contrast, the number of bromodeoxyuridine-incorporating cells was significantly decreased on hydroxyapatite compared with plastic surfaces. Taken together, our findings indicate that hydroxyapatite enhances osteoblast differentiation while also suppressing growth.     

骨形态发生蛋白2诱导C2C12和MC3T3-E1的成骨分化与自噬

背景：一系列研究表明自噬与分化有密切联系;骨形态发生蛋白2是诱导C2C12、MC3T3-E1成骨分化经典途径,是研究成骨分化过程的理想模型。 目的：观察自噬与骨形态发生蛋白2诱导细胞株C2C12、MC3T3-E1成骨分化的关系。 方法：Real-Time PCR检测MC3T3-E1与C2C12在骨形态发生蛋白2(100 μg/L)诱导培养3 d后成骨与自噬相关指标变化。碱性磷酸酶染色检测不同浓度3-甲基腺嘌呤(0,1,5,10 mmol/L)对骨形态发生蛋白2(100 μg/L)诱导培养7 d MC3T3-E1与C2C12成骨指标碱性磷酸酶变化,Western Blot检测C2C12和MC3T3-E1在骨形态发生蛋白2(100 μg/L)诱导不同时间点(0,12,24,48,72,96 h)LC3-Ⅰ/Ⅱ蛋白表达水平。 结果与结论：在骨形态发生蛋白2诱导细胞株C2C12、MC3T3-E1成骨分化过程中,诱导自噬相关mRNA与蛋白水平均有增高趋势,且自噬相关蛋白LC3水平增高与时间相关。同时,抑制自噬成骨分化过程中碱性磷酸酶表达水平降低。因此,自噬与骨形态发生蛋白2诱导细胞株C2C12、MC3T3-E1成骨分化过程有密切关系。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：