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91.
AIM: To explore the neuroprotective effect of novel Rho kinase inhibitor FSD-C10 on Alzheimer disease (AD) model of APP/PS1 double transgenic (Tg) mice. METHODS: Male APP/PS1 Tg mice (n=20) at 8 months of age were randomly divided into 2 groups:model group and FSD-C10 treatment group. The mice were treated with normal saline or FSD-C10 (25 mg·kg-1·d-1) by intraperitoneal injection, once daily for 2 months. Age-and sex-matched wild-type (WT) mice without treatment were used as the control. The Morris water maze (MWM) test and SMART 3.0 behavioral record system were applied to examine and analyze the spatial cognitive function of the mice. The protein levels and distribution of Aβ, p-tau and synapse-associated proteins such as synaptophysin, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and postsynaptic density protein 95 (PSD-95) were determined by immunofluorescence staining. The protein levels of phosphorylated amyloid precursor protein at Thr668[p-APP(Thr668)], beta-site APP-cleaving enzyme 1 (BACE1) and synapse-associated proteins in the brain were analyzed by Western blot. RESULTS: Compared with model group, FSD-C10 treatment significantly improved the cognitive function of the APP/PS1 Tg mice, accompanied by reduced Aβ deposition and p-tau level, increased protein level of p-APP (Thr668) in the central nervous system, decreased expression of BACE1, and increased expression of synapse-associated proteins in the brain of the mice (P<0.05). CONCLUSION: FSD-C10 has neuroprotective potential in the APP/PS1 Tg mice. The mechanism may be related to enhancing the non-amyloidogenic APP cleavage pathway, reducing the production of Aβ oligomers, the deposition of senile plaques and the amount of tau protein, up-regulating synapse-associated proteins, and increasing synaptic plasticity.  相似文献   
92.
自CRISPR/Cas9(clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9)基因 组编辑技术发现以来,迅速在作物中得到广泛应用。但是,CRISPR/Cas9多基因编辑系统在大豆中的研究尚待开 发。本文利用CRISPR/Cas9介导的多基因编辑系统,分别构建了两个载体,一个载体含6个靶点,编辑7个大豆基因 (4个Glycine max ASYMMETRIC LEAVES1(GmAS1)同源基因和3个GmAS2 同源基因),另一个载体含8个靶点,编辑 11个G. max AGAMOUS 家族同源基因(4个GmAG 同源基因,2个G. max SEEDSTICK(GmSTK)同源基因和5个G. max SHATTERPROOF1(GmSHP1/2)同源基因)。大豆遗传转化后,经表型鉴定和靶点检测发现,CRISPR/Cas9介导的多 基因编辑系统在大豆中成功实现了多基因编辑。当3个GmAS1 同源基因和3个GmAS2 同源基因同时突变时,导致 大豆叶片向远轴面弯曲、皱缩且叶柄变短的表型。当2个GmSHP1 同源基因和2个GmSTK 同源基因同时突变时,导 致豆荚停止发育的不育表型。  相似文献   
93.
Weaning may cause oxidative injury, immune response impairment, apoptosis and other injuries in piglets. Oxidative and endoplasmic reticulum stress (ERS) can elicit inflammatory responses, and persistent oxidative and ERS also may lead to apoptotic cascades, which is associated with the pathogenesis of multiple diseases. β-carotene, a natural carotenoid, has potential anti-inflammatory and antioxidant functions. However, the effect of β-carotene on apoptosis in weaned piglets and the detailed molecular mechanism remain unclear. In this study, we found that β-carotene decreased malondialdehyde (MDA) levels and increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in piglet serum. β-carotene could inhibit the mRNA levels of caspase-3 significantly, but had no significant inhibitory effect of the mRNA levels of caspase-9 and caspase-12 in the piglet jejunum. In addition, β-carotene decreased the activation of GRP78, CHOP, and JNK/p38 MAPK and the ratio of Bax/Bcl-2. Furthermore, β-carotene had a significant influence on the activation of ERS and apoptosis-related signals in TG-induced IPEC-J2. In the present study, β-carotene pre-treatment attenuated the ratio of Bax/Bcl-2 and prevented TG-induced increases in the level of PERK-CHOP and IRE1-JNK/p38 MAPK pathway activation in a dose-dependent manner. Overall, these findings indicate that β-carotene may protect weaning-induced apoptosis through inhibiting ERS.  相似文献   
94.
AIM To investigate the role of monocyte chemoattractant protein-1 (MCP-1) and its receptor CC chemokine receptor 2 (CCR2) in ethanol-promoted breast cancer angiogenesis and the underlying mechanism. METH?ODS: A mouse model of transplanted breast tumor with moderate alcohol consumption was established. The correlations between the expression of MCP-1/CCR2 and the expression of angiogenesis markers [platelet endothelial cell adhesion molecule-1 (PECAM-1) and vascular endothelial growth factor (VEGF)] in tumor tissues were examined by immunohistochemistry. In vitro, a 3D tumor-endothelial co-culture system was established to observe tumor angiogenesis and the role of MCP-1/CCR2 signaling pathway in alcohol-mediated angiogenesis. The cell migration ability was detected to clarify whether MCP-1/CCR2 enhanced cell mobility to form new vessels. RESULTS MCP-1 and CCR2 were both highly expressed in the breast tumor tissues of tumor-bearing mice consuming alcohol, and their expression levels were consistent with the angiogenic markers PECAM-1 and VEGF (P<0.05). The interaction between mouse breast cancer E0771 cells and endothelial cells was observed to promote angiogenesis in the 3D tumor-endothelial co-culture system with or without alcohol stimulation. MCP-1 promoted this kind of tumor angiogenesis, while CCR2 antagonist effectively inhibited the tumor angiogenesis and especially blocked alcohol-induced angiogenesis. Activation of MCP-1/CCR2 signaling pathway enhanced the migration ability of endothelial cells. CONCLUSION The MCP-1/CCR2 signaling pathway plays an important role in promoting the angiogenesis of breast cancer stimulated by alcohol. The mechanism might be that MCP-1 improves the migration of endothelial cells and then promotes angiogenesis.  相似文献   
95.
XIA Jun  YU Ting  ZHAO Lei 《园艺学报》2020,36(6):1020-1026
AIM To investigate the role of fatty acid translocase (FAT/CD36) on differentiation of monocytes to macrophages. METHODS Human monocyte THP-1 cells were treated with phorbol 12-myristate 13-acetate (PMA) at 0, 100 and 200 μg /L. Small interfering RNA (siRNA) targeting CD36 (siCD36) was employed to knock down the expression of CD36 in THP-1 cells. The CD36 over-expression (CD36OE) cell line was constructed by transfection with a recombinant lentivirus containing CD36 cDNA. Optical microscopy and crystal violet staining were used to detect the monocyte morphological changes and adhesion ability. The protein expression of CD36 was measured by flow cytometry and Western blot. The mRNA levels of CD36, CD11b and CD80 were detected by real-time PCR. The protein levels of extracellular signal-regulated kinase (ERK) and Src tyrosine kinase were determined by Western blot. RESULTS The cellular adhesiveness of THP-1 cells was elevated in the process of monocytes differentiation, and the expression of CD36 was increased in this process as well (P<0.01). siCD36 was transfected into the THP-1 cells (CD36i group) and the silencing efficiency was approximately 80%. The cell surface area and cellular adhesiveness were significantly decreased in CD36i group compared with scrambled siRNA (NCi) group (P<0.01). The mRNA levels of CD11b and CD80 were decreased in CD36i group compared with NCi group (P<0.01). The cell surface area and cellular adhesiveness were increased in CD36OE group compared with empty vector (vector) group (P<0.05). The mRNA levels of CD11b and CD80 were increased in CD36OE group compared with vector group (P<0.01). The phosphorylation levels of ERK and Src were decreased in CD36i group compared with NCi group (P<0.05). CONCLUSION CD36 promotes the differentiation of human monocyte THP-1 cells to macrophages by increasing the phosphorylation of Src and further activating ERK.  相似文献   
96.
AIM To explore the effect of platelet-rich plasma (PRP) on rabbit osteoarthritis and its possible mechanism. METHODS The rabbits with knee osteoarthritis were prepared and then divided into model group, sodium hyaluronate (SH) group and PRP group, and another sham operation group was set up, with 6 rabbits in each group. The gross morphological changes of rabbit cartilage were observed. HE staining was used to evaluate the pathomorphological changes of the cartilage. TUNEL staining was used to detect the apoptosis of chondrocytes. The expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)/interleukin-1β (IL-1β) signaling pathway-related molecules was observed by immunohistochemical staining, and the protein levels of caspase-3, Bcl-2 and Bax were determined by Western blot. Chondrocytes were isolated and processed according to grouping, and the NLRP3 and IL-1β levels of the cells were measured by ELISA. RESULTS Compared with sham operation group, Pelletier score, Mankin score, chondrocyte apoptotic rate, the positive protein expression rates of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in model group were increased significantly (P<0.05), while the protein expression of Bcl-2 was decreased significantly (P<0.05). Compared with model group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in SH group and PRP group were decreased significantly (P<0.05), while the protein expression of Bcl-2 was increased significantly (P<0.05). In PRP group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax were lower than those in SH group, while the protein expression of Bcl-2 was higher than that in SH group (P<0.05). Compared with control group, the expression of NL?RP3 and IL-1β in MCC950 (NLRP3 ihibitor) group were significantly reduced (P<0.05), the expression of NLRP3 in eucalyptol (IL-1β inhibitor) group was not significantly changed (P>0.05), and the expression of IL-1β was significantly reduced (P<0.05). CONCLUSION Platelet-rich plasma promotes the repair of cartilage in osteoarthritis rabbits, which has better effect than SH. The mechanism may be related to the inhibition of NLRP3/IL-1β pathway and the reduction of chondrocyte apoptosis.  相似文献   
97.
AIM: To investigate the expression and function of circular RNA_0000231 (circ_0000231) in non-small-cell lung cancer (NSCLC). METHODS: RT-qPCR was used to detect the expression of circ_0000231 in the NSCLC tissues and cell lines. circ_0000231 small interfering RNA (si-circ_0000231) or negative control siRNA of circ_0000231 (NC) was transfected into the NSCLC cells. The proliferation and apoptosis of the NSCLC cells were detected by CCK-8 assay, colony formation assay and flow cytometry, respectively. The expression of cyclin D1 (CCND1) and anti-apoptotic protein Bcl-2 were determined by RT-qPCR and Western blot. RESULTS: The expression of circ_0000231 in the NSCLC tissues and cell lines was significantly up-regulated compared with precancerous tissues and lung epithelial cells BEAS-2B (P<0.05). After transfection of NSCLC cells with si-circ_0000231, the cell viability, colony formation numbers were significantly decreased, and the apoptotic rate in si-circ_0000231 group was significantly increased as compared with NC group (P<0.01). In addition, the results of RT-qPCR and Western blot showed that transfection of si-circ_0000231 inhibited the expression of CCND1 and Bcl-2 (P<0.01). CONCLUSION: The expression of circ_0000231 is significantly increased in the NSCLC tissues and cells. Knock-down of circ_0000231 expression significantly inhibits the proliferation of NSCLC cells.  相似文献   
98.
以朱顶红(Hippeastrum vittatum)叶片为外植体进行离体培养,具有取材方便、试材充足、成本低等优势,但叶片诱导再生率极低,是朱顶红离体培养的一大难题。本试验中分别以‘花孔雀’和‘黑天鹅’朱顶红无菌苗叶片为外植体,探究了不同植物生长调节剂和不同取材部位对不定芽诱导和继代增殖的影响。结果表明:最佳外植体为 MS 培养基中培养 10 d 形成的幼嫩叶片基部(0.5 cm),在光照 16 h · d-1(光照强度 36 μmol · m-2 · s-1)下,不定芽诱导的最适培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 NAA + 2 mg · L-1 TDZ,两个品种的不定芽均以间接途径发生,其中‘花孔雀’在培养 40 d 后形成愈伤组织,55 d形成不定芽,诱导率可达 69.44%;‘黑天鹅’在培养 45 d 后形成愈伤组织,65 d 形成不定芽,诱导率达到 66.67%;最适体细胞胚诱导培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 PIC,‘花孔雀’和‘黑天鹅’的诱导率分别达到 66.67%和 63.89%;最佳不定芽增殖培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 NAA + 1 mg · L-1 TDZ,‘花孔雀’和‘黑天鹅’的增殖系数分别达到 4.67 和 3.46;在不添加植物生长调节剂的 MS培养基中进行生根培养,30 d 后两个品种的生根率均达到 100%;将生根培养 30 d 的小植株转移至室温条件下放置 3 d,摘去封口膜再驯化 3 d 后,移栽至经高温消毒的草炭︰蛭石(体积比)为 1︰1 的基质中,成活率达到 100%  相似文献   
99.
管翠萍  杨亚珺  石晶 《园艺学报》2020,47(8):1521-1529
三角状五肽重复(Pentatricopeptide repeats,PPR)蛋白定位于多种细胞器中,参与细胞核和细胞器中特异单链RNA的转录后修饰和编辑,在植物生长发育的多个阶段均发挥着重要的作用。分别从枸杞(Lycium barbarum)雄性可育系‘宁杞1号’和不育系‘宁杞5号’中克隆了Lb_PPR1基因,并对其编码蛋白质进行理化性质、亚细胞定位、保守结构域、蛋白结构以及系统进化等方面进行预测分析。结果显示,‘宁杞1号’和‘宁杞5号’中Lb_PPR1基因的开放阅读框均为1 977 bp,编码658个氨基酸,但其中存在20个碱基和14个氨基酸的差异。Lb_PPR1蛋白包含14个串联重复的PPR保守基序,属于PLS家族,该蛋白定位在细胞膜和细胞质。二级、三级结构预测显示该蛋白以α螺旋为主。同源进化分析得出Lb_PPR1蛋白与同属茄科的辣椒和烟草PPR蛋白亲缘关系最近。利用实时荧光定量PCR检测Lb_PPR1在枸杞不同组织器官及不同发育阶段花药中的表达特性。结果显示,Lb_PPR1在枸杞不同组织中均有表达,但在可育系花蕾中表达量最高,不育系‘宁杞5号’各组织中表达量均显著低于可育系‘宁杞1号’。以上结果表明,Lb_PPR1基因可能与枸杞花药发育有关。  相似文献   
100.
旨在克隆民猪hnRNPUL1基因全长编码区(complete coding sequence,CDS)序列并进行可变剪接分析,研究其组织表达和亚细胞定位情况。本研究以3头3月龄民猪为试验材料,利用RT-PCR技术克隆hnRNPUL1基因CDS及可变剪接体,应用qRT-PCR检测其在心、肝、脾、肺、肾、胃、大肠、小肠、背肌、腿肌等组织中的表达情况,同时,在生物信息学预测的基础上,通过融合表达绿色荧光蛋白的方法鉴定核定位序列。研究结果表明,猪hnRNPUL1基因(GenBank accession No.:MN399154)CDS全长2 580 bp,预期编码的多肽链存在着hnRNPs家族的特征性结构域——SAP、SPRY和AAA;猪hnRNPUL1普遍表达于所检测的各组织中,其中在脾脏中表达量最高,在腿肌中表达量最低;核定位序列(NLS)位于多肽链的133~430 aa处,与生物学信息学预测的结果存在着偏差;同时获得了2个变异剪接体和11种可变剪接片段。本研究结果对进一步揭示猪hnRNPUL1基因功能及转录调控机制提供了基础。  相似文献   
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