Distribution and localization of fibroblast growth factor-8 in rat brain and nerve cells during neural stem/progenitor cell differentiation

The present study explored the distribution and localization of fibroblast growth factor-8 and its potential receptor, fibroblast growth factor receptor-3, in adult rat brain in vivo and in nerve cells during differentiation of neural stem/progenitor cells in vitro. Immunohistochemistry was used to examine the distribution of fibroblast growth factor-8 in adult rat brain in vivo. Localization of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in cells during neural stem/progenitor cell differentiation in vitro was detected by immunofluorescence. Flow cytometry and immunofluorescence were used to evaluate the effect of an anti-fibroblast growth factor-8 antibody on neural stem/progenitor cell differentiation and expansion in vitro. Results from this study confirmed that fibroblast growth factor-8 was mainly distributed in adult midbrain, namely the substantia nigra, compact part, dorsal tier, substantia nigra and reticular part, but was not detected in the forebrain comprising the caudate putamen and striatum. Unusual results were obtained in retrosplenial locations of adult rat brain. We found that fibroblast growth factor-8 and fibroblast growth factor receptor-3 were distributed on the cell membrane and in the cytoplasm of nerve cells using immunohistochemistry and immunofluorescence analyses. We considered that the distribution of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in neural cells corresponded to the characteristics of fibroblast growth factor-8, a secretory factor. Addition of an anti-fibroblast growth factor-8 antibody to cultures significantly affected the rate of expansion and differentiation of neural stem/progenitor cells. In contrast, addition of recombinant fibroblast growth factor-8 to differentiation medium promoted neural stem/progenitor cell differentiation and increased the final yields of dopaminergic neurons and total neurons. Our study may help delineate the important roles of fibroblast growth factor-8 in brain activities and neural stem/progenitor cell differentiation.

The hypoxia-inducible factor-1α activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia

Tumor-induced osteomalacia （TIO） is a rare paraneoplastic syndrome in which ectopic production of fibroblast growth factor 23 （FGF23） by non-malignant mesenchymal tumors causes phosphate wasting and bone fractures. Recent studies have implicated the hypoxia-inducible factor-la （HIF-la） in other phosphate wasting disorders caused by elevated FGF23, including X-linked hypophosphatemic rickets and autosomal dominant hypophosphatemia. Here we provide evidence that HIF-la mediates aberrant FGF23 in TIO by transcriptionally activating its promoter. Immunohistochemical studies in phosphaturic mesenchymal tumors resected from patients with documented TIO showed that HIF-la and FGF23 were co-localized in spindle- shaped cells adjacent to blood vessels. Cultured tumor tissue produced high levels of intact FGF23 and demonstrated increased expression of HIF-la protein. Transfection of MC3T3-E1 and Saos-2 cells with a HIF-la expression construct induced the activity of a FGF23 reporter construct. Prior treatment of tumor organ cultures with HIF-la inhibitors decreased HIF-la and FGF23 protein accumulation and inhibited HIF-la-induced luciferase reporter activity in transfected cells. Chromatin immunoprecipitation assays confirmed binding to a HIF-la consensus sequence within the proximal FGF23 promoter, which was eliminated by treatment with a HIF-la inhibitor. These results show for the first time that HIF-la is a direct transcriptional activator of FGF23 and suggest that upregulation of HIF-la activity in TIO contributes to the aberrant FGF23 production in these patients.

Local inhibition of matrix metalloproteinases reduced M2 macrophage activity and impeded recovery in spinal cord transected rats after treatment with fibroblast growth factor-1 and nerve grafts

Alternatively activated macrophages （M2 macrophages） promote central nervous system regeneration. Our previous study demonstrated that treatment with peripheral nerve grafts and fibroblast growth factor-1 recruited more M2 macrophages and improved partial functional recovery in spinal cord transected rats. The migration of macrophages is matrix metalloproteinase （MMP） dependent. We used a general inhibitor of MMPs to influence macrophage migration, and we examined the migration of macrophage populations and changes in spinal function. Rat spinal cords were completely transected at Ts, and 5 mm of spinal cord was removed （group T）. In group R, spinal cord-transected rats received treatment with fibroblast grow th factor- 1 and peripheral nerve grafts. In group RG, rats received the same treatment as group R with the addition of 200 μM GM6001 （an MMP inhibitor） to the fibrin mix. We found that MMP-9, but not MMP- 2, was upregulated in the graft area of rats in group R. Local application of the MMP inhibitor resulted in a reduction in the ratio of arginase-1 （M2 macrophage subset）/inducible nitric oxide synthase-postive cells. When the MMP inhibitor was applied at 8 weeks postoperation, the partial functional recovery observed in group R was lost. This effect was accompanied by a decrease in brain-derived neurotrophic factor levels in the nerve graft. These results suggested that the arginase-1 positive population in spinal cord transected rats is a migratory cell population rather than the phenotypic conversion of early iNOS^＋ cells and that the migration of the arginase-1^＋ population could be regulated locally. Simultaneous application of MMP in- hibitors or promotion of MMP activity for spinal cord injury needs to be considered if the coadministered treatment involves M2 recruitment.

Significance of serum fibroblast growth factor-23 and miR-208b in pathogenesis of atrial fibrillation and their relationship with prognosis

BACKGROUND The incidence and prevalence of atrial fibrillation are increasing each year,and this condition is one of the most common clinical arrhythmias.AIM To investigate the levels and significance of serum fibroblast growth factor 23(FGF-23)and miR-208 b in patients with atrial fibrillation and their relationship with prognosis.METHODS From May 2018 to October 2019,240 patients with atrial fibrillation were selected as an observation group,including 134 with paroxysmal atrial fibrillation and 106 with persistent atrial fibrillation;150 patients with healthy sinus rhythm were selected as a control group.The serum levels of FGF-23 and miR-208 b in the two groups were measured.In the observation group,cardiac parameters were determined by echocardiography.RESULTS The serum levels of FGF-23 and miR-208 b in the observation group were 210.20±89.60 ng/mL and 5.30±1.22 ng/mL,which were significantly higher than the corresponding values in the control group(P<0.05).In the observation group,the serum levels of FGF-23 and miR-208 b in patients with persistent atrial fibrillation were 234.22±70.05 ng/mL and 5.83±1.00 ng/mL,which were significantly higher than the corresponding values in patients with paroxysmal atrial fibrillation(P<0.05).The left atrial dimension(LAD)of patients with persistent atrial fibrillation was 38.81±5.11 mm,which was significantly higher than that of patients with paroxysmal atrial fibrillation(P>0.05).The serum levels of FGF-23and miR-208 b were positively correlated with the LAD(r=0.411 and 0.382,P<0.05).In the observation group,the serum levels of FGF-23 and miR-208 b in patients with a major cardiovascular event(MACE)were 243.30±72.29 ng/mL and 6.12±1.12 ng/mL,which were significantly higher than the corresponding values in patients without a MACE(P<0.05).CONCLUSION The serum levels of FGF-23 and miR-208 b are increased in patients with atrial fibrillation and are related to the type of disease,cardiac parameters,and prognosis.

Expression of fibroblast growth factor-2 and fibroblast growth factor receptor-1 protein in the hippocampus in rats exhibiting chronic stress-induced depression

There is evidence that the expression of members of the fibroblast growth factor （FGF） protein family is altered in post-mortem brains of humans suffering from major depressive disorder. The present study examined whether the expression of fibroblast growth factor-2 （FGF2） and fibroblast growth factor receptor-1 （FGFR1） protein is altered following chronic stress in an animal model. Rats were exposed to 35 days of chronic unpredictable mild stress, and then tested using open-field and sucrose consumption tests. Compared with the control group, rats in the chronic stress group exhibited obvious depressive-like behaviors, including anhedonia, anxiety and decreased mobility. The results of western blot analysis and immunohistochemical analysis revealed a downregulation of the expression of FGF2 and FGFR1 in the hippocampus of rats, particularly in the CA1, CA3 and dentate gyrus. This decreased expression is in accord with the results of post-mortem studies in humans with major depressive disorder. These findings suggest that FGF2 and FGFR1 proteins participate in the pathophysiology of depressive-like behavior, and may play an important role in the mechanism of chronic stress-induced depression.

TRANSFORMING GROWTH FACTOR-β AND FIBROBLAST GROWTH FACTOR INDUCE LENS EPITHELIAL EXPLANT METAPLASIA:IMPLICATIONS FOR THE FORMATION OF SUBCAPSULAR OPACIFICATION

Objective. This study was to investigate the effects of transforming growth factor-β(TGFβ) and fi- broblast growth factor (FGF) in the subcapsular opacification formation of the lens. Methods. Lens epithelial explants from 10-day-old rats were cultured with TGFβ1 or TGFβ2 in the presence of FGF for 5 days, then were examined by light and electron microscopy, and by immunolocal- ization of smooth muscle(α-sm) actin and type I collagen. Results. In TGFβ/FGF-treated explants,extensive proliferation occured, with formation of spindle and star-shaped cells. These cells showed ultrastructure and biochemical features of fibroblast or myofibroblast. Prominent Golgi apparatus and rough endoplaic reticulum were observed in some cells. Intracellular micro- filaments with cytoplasmic dense babies and membrane associated dense bodies, features of smooth muscle cells, were also observed. Some cells showed reactivity to -sin actin antibody. TGFβ/FGF-treated ex- plants were strongly stained with type I collagen antibody. Condusion. In the presence of FGF, TGFβ1 and TGFβ2 induced lens epithelial cell (LEC ) proliferation and transformation into fibroblast or myofibroblast-like cells, with producing of abundant collagen matrix in the explants. The changes are similar to the metaplasia that occurrs in subcapsular opacification of the lens. The findings suggest that TGFβ and FGF plays a role in the pathogenesis of subcapsular opacification of the lens.

GROWTH DIFFERENTIATION FACTOR-5 STIMULATES THE GROWTH AND ANABOLIC METABOLISM OF ARTICULAR CHONDROCYTES

Objective To observe the effect of growth differentiation factor-5 (GDF-5) on the growth and anabolic metabolism of articular chondrocytes. Methods The articular chondrocytes isolated from rats were treated with various concentrations of rmGDF-5, and the growth of chondrocytes measured by MTT assay, the cellular cartilage matrices formation detected sulfated glycosaminoglycan by Alcian blue staining and type Ⅱcollagen by RT-PCR. Results After 7 days culture, MTT assay showed that GDF-5 enhanced the growth of chondrocytes in a dose-dependent manner, RT-PCR showed that GDF-5 clearly induced the synthesis of type Ⅱ collagen because of the col2a1 mRNA band more and more strong in a dose-dependent. Chondrocytes were cultured with GDF-5 for 14 days, the intensity of Alcian blue staining was greatly enhanced, especially, at a high concentration of 1000ng/mL, and GDF-5 enhanced the accumulation of the Alcian blue-stainable material in a concentration-dependent manner and in a does-dependent manner. Conclusion GDF-5 enhanced the growth of mature articular chondrocytes, and stimulated the cellular cartilage matrices formation in mono-layer culture.

RNA interference affects tumorigenicity and expression of insulin-like growth factor-1,insulin-like growth factor-1 receptor,and basic fibroblast growth factor-2 in rat C6 glioma cells

BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm） and B （siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES： mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS： All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively （P 〈 0.01）. Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION： siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.

Growth factor-and cytokine-driven pathways governing liver stemness and differentiation

Liver is unique in its capacity to regenerate in response to injury or tissue loss. Hepatocytes and other liver cells are able to proliferate and repopulate the liver. However, when this response is impaired, the contribution of hepatic progenitors becomes very relevant. Here, we present an update of recent studies on growth factors and cytokine-driven intracellular pathways that govern liver stem/pro-genitor cell expansion and differentiation, and the rel-evance of these signals in liver development, regeneration and carcinogenesis. Tyrosine kinase receptor signaling, in particular, c-Met, epidermal growth factor receptors or fibroblast growth factor receptors, contribute to prolifera-tion, survival and differentiation of liver stem/progenitor cells. Different evidence suggests a dual role for the trans-forming growth factor (TGF)-β signaling pathway in liver stemness and differentiation. On the one hand, TGF-βmediates progression of differentiation from a progenitor stage, but on the other hand, it contributes to the expan-sion of liver stem cells. Hedgehog family ligands are nec-essary to promote hepatoblast proliferation but need to be shut off to permit subsequent hepatoblast differentiation. In the same line, the Wnt family and β-catenin/T-cell fac-tor pathway is clearly involved in the maintenance of liver stemness phenotype, and its repression is necessary for liver differentiation during development. Collectively, data indicate that liver stem/progenitor cells follow their own rules and regulations. The same signals that are essential for their activation, expansion and differentiation are good candidates to contribute, under adequate conditions, to the paradigm of transformation from a pro-regenerative to a pro-tumorigenic role. From a clinical perspective, this is a fundamental issue for liver stem/progenitor cell-based therapies.

Correlation between expression of two transforming growth factor-beta 1 receptors and microvascular density in a rat model of cerebral ischemia and reperfusion injury

The effects of transforming growth factor-β1 （TGF-β1） are currently controversial. Whether TGF-β1 promotes or inhibits revascularization under different conditions remains poorly understood. Based on previous studies, the current experiment established rat models of cerebral ischemia and reperfusion injury （IRI）, and demonstrated that pathological and functional damage was also increased after IRI. The most serious damage was observed at 3 days after reperfusion, at which time microvascular density fell to its lowest level. Soon afterwards, microvascular density increased, new collateral circulation was gradually established at 4 to 7 days after reperfusion, and pathological damage and neurological deficits were improved. TGF-β1, activin receptor-like kinase 5 （ALK5） mRNA and protein expression levels increased gradually over time. In contrast, ALK1 mRNA and protein expression decreased over the same period. A significant negative correlation was detected between microvascular density and expression of the ALK5 gene transcript. There was no correlation between microvascular density and ALK1 gene transcriptional expression following cerebral IRI in a rat model. These findings suggest that ALK5, rather than ALK1, is the critical receptor in the TGF-β1 signal pathways after cerebral IRI.

血清FGF1、NT5E、25(OH)D在T2DM伴骨质疏松患者中的表达及与糖脂代谢、骨代谢的关系

目的探讨血清碱性成纤维细胞生长因子1(FGF1)、人胞外5’-核苷酸酶(NT5E)、25-羟维生素D[25(OH)D]在2型糖尿病(T2DM)伴骨质疏松患者中的表达,并分析其与糖脂代谢、骨代谢的关系。方法选取2021年1月至2023年6月郑州大学第五附属医院收治的94例T2DM伴骨质疏松患者,另选取同期94例未伴骨质疏松T2DM患者,分别纳入伴骨质疏松组、未伴骨质疏松组。比较两组血清FGF1、NT5E、25(OH)D水平及糖脂代谢、骨代谢相关指标水平[糖化血红蛋白(HbA1c)、空腹血糖(FPG)、空腹胰岛素(FINS)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、总胆固醇(TC)、稳态模型测算胰岛素抵抗指数(HOMA-IR)、骨碱性磷酸酶(B-ALP)、骨钙素N-端中分子片段(N-MID)、Ⅰ型胶原羧基端肽β-胶原特殊序列(β-CTX)、骨钙素(OCN)、抗酒石酸盐酸性磷酸酶异构体5b(TRACP-5b)、Ⅰ型前胶原氨基端前肽(PⅠNP)];比较不同骨质疏松程度患者血清FGF1、NT5E、25(OH)D水平,分析三项指标与糖脂代谢、骨代谢及骨质疏松程度的相关性,并评估其诊断效能。结果伴骨质疏松组血清FGF1、NT5E、HbA1c、HOMA-IR、TC、N-MID、β-CTX、OCN、TRACP-5b水平高于未伴骨质疏松组,25(OH)D、B-ALP、PⅠNP低于未伴骨质疏松组(P<0.05);不同骨质疏松程度患者血清FGF1、NT5E水平比较,3度患者低于2度患者,2度患者低于1度患者,25(OH)D水平比较,3度患者高于2度患者,2度患者高于1度患者(P<0.05);血清FGF1、NT5E与HbA1c、HOMA-IR、TC、N-MID、β-CTX、OCN、TRACP-5b呈正相关,与B-ALP、PⅠNP及骨质疏松程度呈负相关,血清25(OH)D与HbA1c、HOMA-IR、TC、N-MID、β-CTX、OCN、TRACP-5b呈负相关,与B-ALP、PⅠNP及骨质疏松程度呈正相关,且各指标联合诊断骨质疏松的曲线下面积(AUC)为0.923,大于三指标单独诊断(P<0.05)。结论FGF1、NT5E在T2DM伴骨质疏松患者血清中表达上调,25(OH)D表达下调,各指标水平与糖脂代谢、骨代谢及骨质疏松程度均具有一定相关性,联合检测对骨质疏松具有一定诊断价值,可作为临床诊断疾病的辅助指标。

非酒精性脂肪性肝病合并T2DM患者血清成纤维细胞生长因子-21和分泌型卷曲相关蛋白5水平变化及其临床意义探讨

目的探讨非酒精性脂肪性肝病(NAFLD)合并T2DM患者血清成纤维细胞生长因子-21(FGF21)和分泌型卷曲相关蛋白5(SFRP5)水平变化及其临床意义。方法2020年5月~2023年3月我院诊治的NAFLD患者101例【单纯性脂肪肝(NAFL)64例、非酒精性脂肪性肝炎(NASH)25例和肝硬化(LC)12例】和NAFLD合并T2DM患者81例(NAFL 58例、NASH 16例和LC 7例),检测空腹血糖(FBG)、空腹胰岛素(FINS),计算胰岛素抵抗指数(HOMA-IR)。采用ELISA法检测血清FGF21和SFRP5水平。结果NAFLD合并T2DM患者FBG、血清FINS、HOMA-IR和血清FGF21水平分别为(8.7±1.4)mmol/L、(28.9±5.8)μIU/mL、(11.1±2.7)和(304.8±36.0)pg/mL,均显著高于NAFLD患者【分别为(5.5±1.2)mmol/L、(20.8±4.1)μIU/mL、(5.1±1.5)和(267.6±34.5)pg/mL,P<0.05】,而血清SFRP5水平为(6.8±1.2)pg/mL,显著低于NAFLD患者【(10.3±2.2)pg/mL,P<0.05】;NAFLD合并T2DM患者血清TC、TG、HDL-C和LDL-C水平分别为(6.7±1.0)mmol/L、(3.7±0.6)mmol/L、(1.3±0.2)mmol/L和(3.4±0.8)mmol/L,与NAFLD患者【分别为(6.2±0.9)mmol/L、(4.1±0.5)mmol/L、(1.3±0.3)mmol/L和(3.2±0.7)mmol/L】比,差异无统计学意义(P>0.05);T2DM合并NAFL、合并NASH和合并肝硬化患者血清SFRP5水平分别为(7.8±1.1)pg/mL、(6.4±0.8)pg/mL和(5.1±0.7)pg/mL,显著低于NAFL、NASH和肝硬化患者【分别为(11.9±2.1)pg/mL、(9.8±1.6)pg/mL和(8.4±1.1)pg/mL,P<0.05】,而血清FGF21水平分别为(295.6±31.2)pg/mL、(316.8±32.9)pg/mL和(353.6±36.7)pg/mL,显著高于NAFL、NASH和肝硬化患者【分别为(255.1±32.5)pg/mL、(279.5±33.4)pg/mL和(309.7±35.8)pg/mL,P<0.05】。结论NAFLD合并T2DM患者血清FGF21水平显著升高,而血清SFRP5水平显著降低,可应用于对病情严重程度的评估,值得深入研究。

山羊FGF5基因cDNA分子克隆及序列分析

采用逆转录-聚合酶链式反应(RT-PCR)技术,首次从山羊脑组织总RNA中扩增出成纤维细胞生长因子5(FGF 5)基因的cDNA编码序列.通过对序列的分析表明,克隆的山羊FGF 5cDNA编码序列与其他动物的序列具有高度的同源性.与G enbank中人和小鼠序列比较,山羊与人和小鼠的FGF 5核苷酸序列的同源性分别为91%和87%.编码的氨基酸序列比较,山羊和人的相似性为87%,山羊与小鼠的相似性为83%.如FGF s家族的其他成员一样,山羊的FGF 5蛋白也有一信号肽序列.山羊FGF 5基因外显子在编码氨基酸时,对同义密码子的使用表现有强烈的偏好性.不同物种对同义密码子使用的偏倚程度与偏好类型各不相同,也具有种属特异性.山羊FGF 5基因所编码的蛋白质中,20种氨基酸的含量差异很大,极性氨基酸含量高于非极性氨基酸含量.

不同发育阶段绒山羊皮肤中FGF5基因mRNA表达的RT-PCR检测

为深入研究成纤维细胞生长因子5对毛囊生长发育的生物学功能提供理论依据。在10月左右和1月左右,即皮肤毛囊处于生长旺期和退行期时采集了12只内蒙古阿尔巴斯白绒山羊皮样,利用TRIZOL试剂盒提取皮肤总RNA(一步法),利用RT-PCR方法检测FGF5基因在绒山羊绒毛周期性生长不同阶段皮肤中的表达分布情况,试验结果表明,FGF5基因mRNA在绒山羊毛囊生长旺期和退行期均有表达,却只得到了一种剪切形式的表达,经测序是长片段,而缺失外显子2的短片段形式没有检测到。

FGF5在青年羊驼背部和耳部皮肤中的表达和定位

羊驼是毛用型经济动物,其耳部和背部的毛发品质和生长周期存在差异.据研究成纤维细胞生长因子5(fibroblast growth factor 5,FGF5)在多种哺乳动物中影响毛发长度.FGF5基因的突变导致小鼠、狗和猫隐性的长发表型,其也参与了家兔绒毛长度的变异.本实验旨在研究FGF5在青年羊驼皮肤中的表达和定位,以及在羊驼背部和耳部皮肤中的差异比较,探讨其在羊驼毛发生长发育过程中的作用及其相关机制.实验采用实时荧光定量PCR、Western印迹和免疫组织化学等技术,对FGF5在青年羊驼背部和耳部皮肤中的mRNA、蛋白表达水平和定位进行了研究.实时荧光定量PCR结果显示,FGF5在青年羊驼耳部皮肤组织中相对基因表达量是羊驼背部皮肤组织的2.5265倍(P<0.01);Western印迹结果显示,羊驼皮肤组织粗蛋白提取物中存在与兔抗FGF5多克隆抗体发生免疫阳性反应的蛋白条带,羊驼耳部皮肤平均蛋白表达量显著高于背部;免疫组织化学结果显示,FGF5在羊驼皮肤的毛根鞘,毛母质细胞和毛髓质等部位均表达,根据光密度值得出,该蛋白在羊驼背部和耳部皮肤中的表达差异极显著(P<0.01).试验结果提示FGF5可能抑制了羊驼毛发的生长.

TALENs编辑绵羊成纤维细胞FGF 5基因

类转录激活因子效应物(Transcription activator-like effector,TALE)已经成为基因组编辑和基因转录调控的有效工具,在多个物种的基因组中实现特定位点的删除、插入和突变。针对绵羊成纤维细胞生长因子5(Fibroblast growth factor 5,FGF5)基因起始密码子ATG位点,设计构建TALENs(Transcription activator-like effector nucleases,TALENs)。通过比较分析正常培养和基因组编辑处理的绵羊成纤维细胞,电转TALENs组合,Surveyor突变检测,筛选获得1对有效的TALENs。有限稀释细胞传代培养,PCR扩增FGF5基因片段,经PAGE检测筛选发生突变的细胞,测序确认FGF5基因ATG位点产生缺失突变细胞。获得具有编辑活性的TALENs,为该基因的定点编辑奠定基础。Surveyor检测和测序结果表明,在绵羊FGF5基因ATG起始密码子上游104碱基位点,存在1个G/C单核苷酸多态。

碱性成纤维细胞生长因子和5-氮杂胞苷对大鼠骨髓间充质干细胞分化潜能和细胞增殖的影响

目的:探讨碱性成纤维细胞生长因子(bFGF)和5-氮杂胞苷(5-aza)对体外骨髓间充质干细胞(MSCs)细胞增殖与分化潜能的影响。方法:大鼠骨髓中获得MSCs,培养传代,在倒置相差显微镜和透射电镜下观察细胞形态变化;流式细胞仪检测细胞周期改变;MTT法检测bFGF和5-aga对MSCs生长的影响;免疫细胞化学方法检测actin、desmin、myoglobin、NSE、GFAP的表达。结果:有心肌样细胞和神经元样细胞的形态变化;MSCs经5-aza以及5-aza加bFGF联合诱导actin、desmin、myoglobin、NSE和GFAP的表达均较对照组显著增高;而经bFGF诱导后,前4种蛋白表达无明显变化,仅GFAP蛋白表达显著增高。结论:5-aza对MSCs细胞生长有抑制作用,而bFGF有明显促增殖作用。MSCs被5-aza诱导分化成心肌样细胞和神经元样细胞,bFGF可使MSCs分化为GFAP阳性的神经胶质样细胞。

NGF和FGF对移植的兔5-HT、DA能性神经元的影响

本实验将含有5—HT和DA能性神经元的胎兔脑组织微块液用立体定向法移植至成年兔脑内。兔21只分为三组,每组7只:第一组加入NGF,第二组加FGF,第三组未加任何因子列为对照组。移植2个月后用高效液相色谱电化学法(HPLC-EC)测定移植神经元的递质(5-HT、DA)含量。结果显示1、2两组的5-HT和第二组DA含量均显著高于对照组(P<0.05,P<0.01)。因此,表明NGF和FGF可能具有促进移植神经元存活和分化的功能。

内蒙古白绒山羊FGF5基因克隆及其靶向shRNA表达载体的构建和鉴定

旨在构建内蒙古白绒山羊成纤维细胞生长因子Ⅴ(Fibroblast growth factor 5,FGF5)基因shRNA真核表达载体(pRNAT-shRNA)。以内蒙古白绒山羊胎儿成纤维细胞总RNA为模板,PCR扩增FGF5基因。设计并合成3条FGF5基因的靶向shRNA序列,分别插入pRNAT-U6.1/Neo载体中,构建重组干扰质粒载体pRNATshRNA1、pRNAT-shRNA2和pRNAT-shRNA3,用脂质体LipofectamineTM2000将各重组干扰质粒转染内蒙古白绒山羊胎儿成纤维细胞,Real time PCR检测FGF5mRNA表达量。结果表明:克隆获得813bp的目的基因,包含了完整的ORF,编码270个氨基酸。核苷酸序列及推导的氨基酸序列与绵羊FGF5基因(NM_001246263.1)及氨基酸序列同源性均为99%。FGF5基因shRNA重组质粒经测序鉴定证明构建成功。重组表达质粒转染绒山羊胎儿成纤维细胞48h后可见绿色荧光表达;pRNAT-shRNA1组、pRNAT-shRNA2组和pRNAT-shRNA3组FGF5的mRNA表达水平均低于干扰空载体对照组(P<0.01),pRNAT-shRNA2对FGF5的表达具有最佳的抑制效应。综上表明,成功构建pRNAT-U6.1/Neo-FGF5表达载体,为探讨FGF5在毛囊生长中的作用奠定了基础。

生长分化因子-5及碱性成纤维细胞生长因子诱导家兔椎间盘髓核细胞成骨作用的研究

目的建立家兔椎间盘髓核细胞的体外培养模型,研究重组人生长分化因子-5(recombinant human growth differentiation factor-5,rhGDF-5)和碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)对髓核细胞成骨潜能的激发作用。方法将诱导剂rhGDF-5和bFGF分别及联合加入体外培养的髓核细胞中,观察髓核细胞的成骨表型表达和细胞学特性的变化。结果 rhGDF-5和bFGF均能促进钙盐沉积形成钙结节。rhGDF-5抑制髓核细胞增殖同时增加骨钙素表达;bFGF促进髓核细胞增殖及Ⅰ型胶原表达,但对骨钙素表达无显著影响。联合使用rhGDF-5和bFGF对髓核细胞成骨潜能(促进髓核细胞增殖、Ⅰ型胶原及骨钙素表达和钙盐沉积)的激发作用均优于单独使用其中任一细胞因子。结论 rhGDF-5诱导髓核细胞向成骨细胞分化,bFGF加强该诱导作用,联合使用rhGDF-5和bFGF能充分激发髓核细胞的成骨潜能。