New approaches to moderate CRISPR-Cas9 activity: Addressing issues of cellular uptake and endosomal escape

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治伤巴布剂对大鼠急性软组织损伤模型P38MAPK、AKT信号通路的影响＊

目的 观察治伤巴布剂对急性软组织损伤（acute soft tissue injury， ASTI）模型p38丝裂原活化蛋白激酶（mitogen-activated protein kinase，MAPK）、丝/苏氨酸蛋白激酶（AKT）信号通路的影响，探讨治伤巴布剂干预ASTI的可能作用机制。方法 将40只雄性SD大鼠按照随机数字表法分为正常对照组、模型对照组、治伤巴布剂组、p38MAPK信号通路抑制剂组、AKT信号通路抑制剂组，每组8只。除正常对照组外，其余四组均予以左侧后肢小腿ASTI造模。造模成功后，治伤巴布剂组于标记部位立即予治伤巴布剂（修剪成1.5x3cm大小）外敷，并用胶布固定；其余四组均予等剂量赋形剂（修剪成1.5×3 cm大小）外敷处理，胶布固定；持续外敷，共持续24 h。p38MAPK信号通路抑制剂组在造模前30 min予腹腔注射p38MAPK信号通路抑制剂SB203580（400 μg/kg/天）1次；AKT信号通路抑制剂组在造模前30 min予腹腔注射AKT信号通路抑制剂perifosine（20 mg/kg/天）1次。分别于0（造模前）、2h、4h、8h、12h、24h测量受伤小腿肌肉处的周长，并计算肌肉肿胀率（muscle swelling rate，MSR）。24 h药物干预结束后，采用颈椎脱臼法处死大鼠。后将左侧后肢小腿损伤中心部位进行取材，分成三份。一部分用于观察组织病理学形态变化；一部分用于逆转录聚合酶链反应（RT-PCR）检测核因子-κB（nuclear factor kappa-B，NF-κB）p65 mRNA、肿瘤坏死因子-α（TNF-α）mRNA、白细胞介素-1β（IL-1β）mRNA表达水平；剩下部分用酶联免疫吸附试验（ELISA）法检测骨骼肌组织TNF-α、IL-1β含量水平及蛋白质免疫印迹（Western-blot）法测定p38MAPK、AKT、NF-κB p65、核因子抑制蛋白α（inhibitor kappa B alpha， IκBα）表达水平。结果 与正常对照组相比，模型对照组MSR显著增加（P<0.01）；病理形态学上，骨骼肌组织可见大面积肌细胞排列紊乱，肌细胞变性坏死，间质内可见红细胞聚集及大量炎症细胞浸润；骨骼肌组织TNF-α、IL-1β含量水平显著升高（P<0.01）；磷酸化p38MAPK（p-p38）/总p38MAPK（t-p38），磷酸化-AKT（p-AKT）/总-AKT（t-AKT）明显升高（P<0.01），NF-κB p65及NF-κB p65mRNA表达水平明显升高（P<0.01）。与模型对照组相比，治伤巴布剂组MSR在治疗第8 h、12 h、24 h显著下降（P<0.01），且在治疗第24 h，其MSR较p38MAPK、AKT信号通路抑制剂组下降更明显（P<0.05）；病理学评分显著下降（P<0.01），且较p38MAPK、AKT信号通路抑制剂组下降更显著（P<0.05）；骨骼肌组织TNF-α、IL-1β含量水平明显下降（P<0.01），且较p38MAPK、AKT信号通路抑制剂组更显著（P<0.05）；p-p38/t-p38及p-AKT/t-AKT明显下降（P<0.01），NF-κB p65及NF-κB p65 mRNA表达水平显著下降（P<0.01），且较p38MAPK、AKT信号通路抑制剂组在降低NF-κB p65及NF-κB p65 mRNA相对表达值方面更显著（P<0.01）。结论 治伤巴布剂可能同时对p38MAPK、AKT信号通路产生了一定的抑制作用，引起NF-κB活性下调，NF-κB p65蛋白的表达下调，进而引起骨骼肌组织TNF-α、IL-1β炎性细胞因子含量水平下调，减轻ASTI炎症反应，从而改善ASTI。     

地鳖纤溶蛋白口服时间/pH依赖结肠靶向微囊的开发及评价＊

地鳖中的纤溶活性蛋白是从地鳖中提取的具有抗栓及抗肿瘤作用的有效成分，其口服易被上消化道酶分解从而限制了应用。采用恒流泵滴制法开发地鳖纤溶活性蛋白时间/pH依赖口服结肠靶向微囊（EnpolypHaga fibrinolytic protein oral colon targeting microcapsules， CTM-EFP）。采用单因素实验和正交实验相结合的方法寻找到包封率为60.17 % ± 2.72 %、载药量为15.50 % ± 0.44 % 的最佳配方。扫描电子显微镜（SEM）显示微囊呈球形、表面光滑，在人工肠液中24 h的累积释放度为99.53 % ± 0.69 %，在人工胃液中24 h累积释放度为7.43 ± 1.04 %，通过时间/pH依赖达到结肠靶向作用。CTM-EFP在人工肠液中的体外释放曲线符合Korsmeyer方程，提示地鳖纤溶活性蛋白（EnpolypHaga fibrinolytic protein， EFP）是通过扩散和侵蚀机制结合释放的。CTM-EFP为EFP的口服给药提供了一种新的剂型，为EFP应用于临床提供参考。     

Knockdown of DEAD-box 51 inhibits tumor growth of esophageal squamous cell carcinoma via the PI3K/AKT pathway

BACKGROUND Esophageal squamous cell carcinoma(ESCC)is one of the most prevalent malignancies that seriously threaten people’s health worldwide.DEAD-box helicase 51(DDX51)is a member of the DEAD-box(DDX)RNA helicase family,and drives or inhibits tumor progression in multiple cancer types.AIM To determine whether DDX51 affects the biological behavior of ESCC.METHODS The expression of DDX51 in ESCC tumor tissues and adjacent normal tissues was detected by Immunohistochemistry(IHC)analyses and quantitative PCR(qPCR).We knocked down DDX51 in ESCC cell lines by using a small interfering RNA(siRNA)transfection.The proliferation,apoptosis,and mobility of DDX51 siRNAtransfected cells were detected.The effect of DDX51 on the phosphoinositide 3-kinase(PI3K)/AKT pathway was investigated by western blot analysis.A mouse xenograft model was established to investigate the effects of DDX51 knockdown on ESCC tumor growth.RESULTS DDX51 exhibited high expression in ESCC tissues compared with normal tissues and represented a poor prognosis in patients with ESCC.Knockdown of DDX51 induced inhibition of ESCC cell proliferation and promoted apoptosis.Moreover,DDX51 siRNA-expressing cells also exhibited lower migration and invasion rates.Investigations into the underlying mechanisms suggested that DDX51 knock down induced inactivation of the PI3K/AKT pathway,including decreased phosphorylation levels of phosphate and tensin homolog,PI3K,AKT,and mammalian target of rapamycin.Rescue experiments demonstrated that the AKT activator insulin-like growth factor 1 could reverse the inhibitory effects of DDX51 on ESCC malignant development.Finally,we injected DDX51 siRNA-transfected TE-1 cells into an animal model,which resulted in slower tumor growth.CONCLUSION Our study suggests for the first time that DDX51 promotes cancer cell proliferation by regulating the PI3K/AKT pathway;thus,DDX51 might be a therapeutic target for ESCC.     

Artificial intelligence and clinical data suggest the T cell-mediated SARS-CoV-2 nonstructural protein intranasal vaccines for global COVID-19 immunity

Advanced computational methodologies suggested SARS-CoV-2, nonstructural proteins ORF1AB, ORF3a, as the source of immunodominant peptides for T cell presentation. T cell immunity is long-lasting and compatible with COVID-19 pathology. Based on the supporting clinical data, nonstructural SARS-CoV-2 protein vaccines could provide global immunity against COVID-19.     

基于网络药理学和分子对接技术分析筒鞘蛇菰多糖治疗肝损伤的作用机制及体内实验研究＊

目的 基于网络药理学探讨并分析筒鞘蛇菰（Balanophora involucrata Hook. f.，BIH）治疗肝损伤的作用及分子机制，并通过大鼠体内实验验证相关预测靶点及筒鞘蛇菰提取物-蛇菰多糖（Polysaccharides of Balanophora involucrata Hook. f.，BPS）对实验性肝损伤的保护作用。方法 化学专业数据库、TCMID和TCMSP平台检索筒鞘蛇菰组成的化合物及可能靶点，以肝损伤为关键词检索GeneCards和网站，获得相关靶点，绘制Venn图，选交集靶点，将“化合物-靶点和疾病-靶点”关系导入Cytoscape V3.7.2软件，获得化合物-靶点-疾病的三重网络，对化合物及相关靶点蛋白行分子对接，并用交集靶点绘制蛋白互作网络图及进行GO生物功能和KEGG信号途径富集分析。结果 筒鞘蛇菰主要成分有11个化合物，其中与肝损伤有37个交集靶点，高度关联靶点包括NOS3、ESR1、TNF、MAOA、PTGS2、IL10等，GO和KEGG富集分析发现筒鞘蛇菰治疗肝损伤的分子机制，可能与调节肾上腺素能信号通路、cGMP-PKG信号及神经活性配体-受体交互通路等有关，而且ADRA1B、ADRA2A、ADRA2C、ADRB1/2等基因高度富集于这些通路中。动物体内实验发现BPS灌胃处理可减轻肝组织损伤、调控血清炎症因子肿瘤坏死因子α（Tumor necrosis factor， TNF-α）和白细胞介素10（IL-10）水平、提高抗氧化酶超氧化物歧化酶（superoxide dismutase，SOD）活性，并增强肝组织内氧化应激相关蛋白核因子E2相关因子2（NF-E2-related factor 2，NRF2）和醌NADH脱氢酶1（NQO1）的表达，从而抑制大鼠体内氧化应激损伤、减轻炎症反应和细胞凋亡，达到保护实验性肝损伤的作用。结论 本研究初步确定筒鞘蛇菰治疗肝损伤的有效成分、“化合物-蛋白-靶点”关联网络及发挥作用的分子机制，并通过动物体内实验证实蛇菰多糖保护肝损伤的机制与上调NRF2/NQO1通路来减轻氧化应激反应性损伤、减轻肝细胞凋亡有关。     

Mechanism of action of Orthosiphon stamineus against non-alcoholic fatty liver disease: Insights from systems pharmacology and molecular docking approaches

Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components.     

Inverse correlation between the expression of AMPK/SIRT1 and NAMPT in psoriatic skin: A pilot study

PurposeEpidermal hyperplasia and the involvement of immune cells characterize the clinical picture of psoriasis. Among the several factors involved, attention has been focused on sirtuin 1 (SIRT1) - a deacetylase endowed with a variety of functions including the control of metabolic and inflammatory processes-, and on nicotinamide phosphoribosyltransferase (NAMPT), important for SIRT1 activation and involved in inflammatory events. The aim of the study was to analyze changes of SIRT1 and NAMPT expression in psoriatic skin.Patients and methodsSamples from healthy controls and psoriatic patients were subjected to immunohistochemical analysis.ResultsA strong downregulation of SIRT1 expression was observed in skin samples from psoriatic patients compared to healthy controls. This was accompanied by a parallel reduction of adenosine monophosphate-activated kinase (AMPK) expression and, more strikingly, by the disappearance of cells immunolabeled for its active, phosphorylated form (pAMPK). In both cases, analysis of the distribution of immunopositive cells revealed a shift towards reduced intensity of staining. In contrast, NAMPT expression was upregulated in psoriatic samples in line with its pro-inflammatory role. This was again more visible with an intensity-based distribution analysis that evidenced a shift towards more intensely immunostained cell populations.ConclusionsThe present data correlate in the same samples the expression of SIRT1, pAMPK/AMPK and NAMPT in psoriasis and open the way for novel pharmacological targets in the treatment of the disease.