全反式维甲酸对兔动脉粥样硬化病灶中MCP-1 和TLR-4

目的:观察全反式维甲酸(ATRA)对兔颈动脉粥样硬化性病灶中内膜增生、MCP-1及TLR-4表达的影响,探讨其可能的抗炎机制。方法:新西兰雄性大白兔随机分为9组(n=6):对照组(A、B、C)、治疗组(A、B、C)、假手术组(A、B、C)。除假手术组外,其余两组给予高脂饮食2周后,对照组及治疗组给予颈动脉内膜空气干燥术损伤颈动脉内膜,假手术组分离暴露颈动脉但不损伤内膜,治疗组术前3天给予ATRA灌胃,直至处死。术后分别于7d、14d、28d处死。采取颈动脉标本,对血管粥样硬化病变进行形态学观察及测定,采用免疫组化法检测MCP-1及TLR-4表达水平。结果:从形态学观察及免疫组化检测看,对照组较假手术组内膜明显增生,MCP-1及TLR-4表达增多,治疗组内膜较对照组增生减轻,两种因子表达减少。结论:全反式维甲酸(ATRA)对兔颈动脉粥样硬化性病灶中的抗炎作用可能是通过抑制MCP-1及TLR-4等炎症因子的表达来发挥作用的。     

全反式维甲酸对急性早幼粒细胞白血病患者血清学的影响

目的：探讨全反式维甲酸（All trans retinoic acid,ATRA）作为辅助剂在急性早幼粒细胞白血病（Acute promyelocytic leukemia, APL）治疗中,对患者血清促红细胞生成素（Erythropoietin,EPO）、血清铁蛋白、叶酸和维生素B12水平的影响。方法：回顾性分析 我院2011 年6 月-2015 年6 月接诊的50 例急性早幼粒细胞白血病患者的临床资料。根据患者的治疗方法不同将患者分为两组, A 组（亚砷酸钠治疗组）和B 组（亚砷酸钠联合ATRA）。对比两组患者治疗后血清铁蛋白、EPO、叶酸和维生素B12 恢复情况。结 果：两组患者入院时所有血清EPO、铁蛋白等比较,差异无统计学意义（P>0.05）;治疗后两组患者血清各指标均有所改善（P<0. 05）;治疗后B 组患者中EPO、血清B12、血清铁蛋白和叶酸恢复正常水平者明显多于A 组,差异具有统计学意义（P<0.05）。结论： 全反式维甲酸辅助治疗急性早幼粒细胞白血病患者能够更好的改善患者血清EPO、铁蛋白、叶酸和维生素B12 的异常,对于疾病 的治疗有一定的效果。     

全反式维甲酸对乙酰胆碱受体特异性淋巴细胞的免疫调控作用

目的:观察全反式维甲酸(ATRA)对乙酰胆碱受体(AChR)特异性淋巴细胞的体外调控作用,探讨其治疗重症肌无力(MG)的可能机制。方法:建立完全弗氏佐剂(CFA)对照组及实验性自身免疫性重症肌无力(EAMG)组大鼠,并获取淋巴结单个细胞悬液,以ACh R97-116多肽片段以及不同浓度的ATRA体外培养72 h,采用流式细胞仪法、CCK-8法、ELISA法分别检测活细胞比例、细胞凋亡和周期的改变以及Th亚群的格局和B细胞抗体分泌能力的变化。结果:ATRA显著降低活细胞比例(P0.001);不同浓度的ATRA均促进了特异性细胞群的凋亡(P0.001),且呈剂量依赖性,而ATRA未改变AChR特异性淋巴细胞的生长周期;ATRA处理后,CFA和EAMG组的淋巴细胞增殖均受到明显抑制,且ATRA对ACh R特异性的淋巴细胞的抑制明显(EAMG组,P0.01)于CFA组(P0.05);ATRA干预后,ACh R特异性CD4+T淋巴细胞的比例下降(P0.01),且ATRA促进了Th2、Treg细胞亚群百分比(P_(IL-4)0.001,P_(Foxp3)0.001),而抑制了促炎性的Th17、Th1细胞亚群百分比(P_(IL-17)0.05,P_(IFN-γ)0.001);ATRA能够降低ACh R特异性B细胞的抗体分泌能力(P0.01)。结论:ATRA不仅能抑制ACh R特异性T细胞功能,同时也能抑制ACh R特异性B细胞功能,其在MG的临床治疗中可能起治疗作用。     

All-trans retinoic acid (ATRA) downregulated MMP-9 by modulating its regulatory molecules

The vitamin A derivative all-trans retinoic acid (ATRA) is considered as a potent chemotherapeutic drug for its capability of regulating cell growth and differentiation. We aimed to study the effect of ATRA on MMP-9 in MDA-MB-231, human breast cancer cells and the probable molecular mechanisms through which ATRA exerts its effect. Results: Our experimental findings demonstrate that ATRA enters into the nucleus and regulates various signaling pathways viz. Integrin, FAK, ERK, PI-3K, NF-κB and also EGFR and down regulates pro-MMP-9 activity as well as its expression. As a result MDA-MB-231 cell migration on fibronectin medium gets retarded in presence of ATRA. ATRA up regulates TIMP-1 expression. Conclusions: Our study may help to understand the role of ATRA as a regulator of MMP-9 and the possible signaling pathways which are involved in this ATRA mediated down regulation of MMP-9.     

All-trans retinoic acid (ATRA) downregulates MMP-9 by modulating its regulatory molecules

The vitamin A derivative all-trans retinoic acid (ATRA) is considered as a potent chemotherapeutic drug for its capability of regulating cell growth and differentiation. We aimed to study the effect of ATRA on MMP-9 in MDA-MB-231, human breast cancer cells and the probable molecular mechanisms through which ATRA exerts its effect. Our experimental findings demonstrate that ATRA enters into the nucleus and regulates various signaling pathways viz. Integrin, FAK, ERK, PI-3K, NFκB and also EGFR and downregulates pro-MMP-9 activity as well as its expression. As a result MDA-MB-231 cell migration on fibronectin medium gets retarded in presence of ATRA. ATRA upregulates TIMP-1 expression. Our study may help to understand the role of ATRA as a regulator of MMP-9 and the possible signaling pathways which are involved in this ATRA mediated downregulation of MMP-9.Key words: MMP-9, ATRA, integrin, EGFR, NFκB     

血清对全反式视黄酸抑制肺癌细胞生长的影响

 研究不同浓度的血清对全反式视黄酸 (ATRA)抑制肺癌细胞生长的影响 .当细胞培养在 10 %血清中 ,ATRA不能抑制肺癌细胞生长 ,但是当细胞培养在 1%血清中 ,ATRA能够有效地抑制肺癌细胞生长 .视黄酸受体RARβ介导视黄酸的抗癌作用 .Northern印迹分析表明 ,在高浓度血清中AT RA不能诱导RARβ表达 ,但在低浓度血清中ATRA可以诱导RARβ表达 ,并且瞬时转染和CAT测定证实是通过激活RABβ启动子转录活性而诱导RARβ表达的 .孤生受体Nur77受到血清生长因子刺激后会大量表达 ,具有抗视黄酸活性的作用 .肺癌细胞培养在低浓度血清中 ,Nur77mRNA低水平表达和Nur77蛋白不表达 .然而在高浓度血清中 ,Nur77mRNA和蛋白高水平表达 .另外 ,在无血清条件下 ,EGF也可以诱导Nur77表达 .结果提示 ,血清中的生长因子可能拮抗ATRA抑制肺癌细胞生长的作用 ,其作用途径可能是通过刺激细胞中Nur77表达 ,或者通过下调RARβ启动子的转录活性而抑制RARβ的表达     

全反式维甲酸对HL-60细胞中N-乙酰氨基葡萄糖转移酶II,IV活力的影响

本文研究全反式视黄酸（ＡＴＲＡ）对ＨＬ－６０细胞中乙酰氨基葡萄糖转移酶ＩＩ和ＩＶ（ＧｎＴ－ＩＩ,ＩＶ）的调控作用,结果发现０．１μｍｏｌ／Ｌ的ＡＴＲＡ即可使ＧｎＴ－ＩＩ和ＩＶ的活力明显降低至５０％左右,但ＡＴＲＡ浓度增至１．０或１０μｍｏｌ／Ｌ时,酶活力不再显著下降。在未经ＡＴＲＡ处理的对照细胞中,培养不同时间两酶活力均有较大的变动,未经同步化和同步化的细胞分别在２４ｈ及至４８ｈ达到高峰。ＡＴＲＡ处理后,未经同步化细胞的酶活力高峰也在２４ｈ,但不论同步化与否,在２４ｈ之前均未见两酶活力的下降,２４ｈ后,酶活力逐步降低。对以上结果作了讨论。     

维甲酸对肝癌细胞HepG2糖基化磷脂酰肌醇特异性磷酯酶D表达及细胞生物学特性的影响

应用MTT、流式细胞仪、免疫印迹法检测全反式维甲酸(ATRA)单独或联合糖基化磷脂酰肌醇特异性磷酯酶D(GPI-PLD)特异性抑制剂1,10-二氮杂菲对肝癌细胞HepG2生物学特性的改变.ATRA使肝癌细胞HepG2 GPI-PLD基因表达及酶活性上调,并呈现剂量和时间依赖性.ATRA可抑制肝癌细胞HepG2增殖,使肝癌细胞Caspase-3表达水平显著增加,Bcl-2表达水平下调,促进肝癌细胞凋亡(P<0.05).ATRA联合1,10-二氮杂菲诱导组细胞,Bcl-2、细胞增殖活性较ATRA单独诱导组显著增强,Caspase-3、凋亡率显著下降.维甲酸可促进肝癌细胞HepG2 GPI-PLD基因表达上调,高活性的GPI-PLD有助于维甲酸抑制肝癌细胞增殖,促进肝癌细胞凋亡.     

Emerging Role of Combination of All-trans Retinoic Acid and Interferon-gamma as Chemoimmunotherapy in the Management of Human Glioblastoma

Glioblastoma is the most malignant and common type of brain tumor with devastating outcome. Because current treatment modalities are mostly ineffective in controlling and curing glioblastoma, new and innovative therapeutic strategies must be developed. This article describes recent advances in chemoimmunotherapy, which is combination of chemotherapy and immunotherapy, against glioblastoma. We provide an overview of available treatment options for glioblastomas, gaps in our knowledge of immune recognition of these malignant tumors, and chemotherapeutic and immunotherapeutic agents that need to be further explored for designing novel chemoimmunotherapeutic strategy for the management of human glioblastomas. Our recent study demonstrated that combination of the chemotherapeutic agent all-trans retinoic acid (ATRA) and the immunotherapeutic agent interferon-gamma (IFN-γ) could concurrently induce differentiation, apoptotic death, and immune components in two different human glioblastoma cell lines. We propose that combination of ATRA and IFN-γ can become an efficacious chemoimmunotherapy for the treatment of human glioblastoma. Special issue in honor of Naren Banik.     

全反式维甲酸及依托泊苷对急性早幼粒细胞白血病细胞磷脂酰丝氨酸暴露及促凝血活性的影响

目的：探讨磷脂酰丝氨酸（PS）暴露在急性早幼粒细胞白血病（APL）细胞促凝血活性中的作用及不同药物对其产生的影响。方法：实验共分为4组：新采集APL细胞组、APL细胞单纯培养组、APL细胞全反式维甲酸（ATRA）处理组及APL细胞依托泊苷（VP16）处理组。提取10名初发APL患者的骨髓APL细胞进行实验,提取10名健康成人外周血单个核细胞作为凝血实验的正常对照。分别用1μmol·L-1ATRA和1μmol·L-1VP16处理APL细胞24 h,利用共聚焦显微镜及流式细胞术检测各组细胞PS暴露情况。利用凝血实验检测各组细胞总的促凝活性及细胞表面磷脂的促凝血活性。利用PS特异结合蛋白乳粘素对各组细胞进行凝血抑制实验。结果：新采集的APL细胞存在一定量的PS外翻,并且与外周血单个核细胞相比,存在更高的促凝血活性（P〈0.05）,ATRA对APL细胞的PS外翻及促凝活性有抑制作用（P〈0.05）,VP16则对其有显著的促进作用（P〈0.001）。乳粘素可以拮抗APL细胞至少70%的促FXa和FIIa生成活性。结论：PS暴露在APL细胞促凝血过程中发挥着重要作用。分化治疗药物ATRA和化疗药物VP16分别通过减少和增加APL细胞表面PS的暴露来减轻和加重凝血紊乱。乳粘素通过与PS特异结合可以有效地阻断暴露的PS的促凝活性,是一种潜在的治疗APL凝血紊乱的抗凝剂。     

全反式维甲酸联合替莫唑胺对胶质瘤U251细胞增殖与凋亡的影响

目的：研究全反式维甲酸（ATRA）联合替莫唑胺（TMZ）对胶质瘤细胞株U251增殖及凋亡的影响。方法：体外培养胶质瘤细胞株U251,分为ATRA组、TMZ组、ATRA＋TMZ组和空白对照4组,应用MTT法测定U251细胞生长抑制率,流式细胞仪检测细胞周期分布和细胞凋亡率,westernblot法检测细胞维甲酸受体β（RARβ）蛋白和凋亡相关蛋白Caspase．3蛋白的表达情况。结果：对照组、ATRA组、TMZ组及ATRA＋TMZ组的细胞生长抑制率分别为（1．72±0．12）％、（9．87±0．87）％、（23．87＋1．32）％及（35．74±1．44）％,ATRA＋TMZ组的细胞生长抑制率显著高于单独应用TMZ（P〈0．01）。对照组、ATRA组、TMZ组及ATRA＋TMZ组的细胞凋亡率分别为（1．32±0．11）％、（4．16±0．35）％、（8．44±0149）％、（15．27±1．03）％,ATRA＋TMZ组的凋亡率显著高于单独应用TMZ有更高的凋亡率（P〈0．01）。对照组、ATRA组、TMZ组及ATRA＋TMZ组RARp蛋白相对表达量分别0．452±0．054、0．837±0．068、0．195±0．021、0．376±0．039,ATRA＋TMZ组RARβ蛋白相对表达量显著高于TMZ组（P〈0．01）。ATRA＋TMZ组Caspase．的3蛋白表达相对水平为（0．832±0．059）,明显高于ATRA组（0．334±0．041）及TMZ组（0．521＋0．032）,差异具有统计学意义（P〈0．01）。结论：全反式维甲酸联合替莫唑胺能更有效抑制U251细胞的增殖,增加其凋亡率,这可能与其增加RARβ和Caspase-3蛋白的表达抑制U251细胞增殖、诱导细胞凋亡有关。     

曲酸的发酵生成与检测(综述)

本文概述曲霉发酵合成曲酸所需的各种营养因素及其对产酸力的影响,发酵工艺与菌种诱变,合成机理,曲酸的鉴定和检测方法,并对发酵工艺的发展趋势提出一些看法。     

Roscovitine enhances All-trans retinoic acid (ATRA)-induced leukemia cell differentiation: Novel effects on signaling molecules for a putative Cdk2 inhibitor

All-trans retinoic acid (ATRA)-based differentiation therapy has been unsuccessful in treating t(15;17) negative acute myeloid leukemia (AML) patients, motivating interest in combination therapies using ATRA plus other agents. Using the t (15, 17) negative HL-60 human myeloblastic leukemia model, we find that the cyclin-dependent kinase (CDK) inhibitor, roscovitine, augments signaling by an ATRA-induced macromolecular signalsome that propels differentiation and enhances ATRA-induced differentiation. Roscovitine co-treatment enhanced ATRA-induced expression of pS259- pS289/296/301- pS621-c-Raf, pS217/221-Mek, Src Family Kinases (SFKs) Lyn and Fgr and SFK Y416 phosphorylation, adaptor proteins c-Cbl and SLP-76, Vav, and acetylated 14–3-3 in the signalsome. Roscovitine enhanced ATRA-induced c-Raf interaction with Lyn, Vav, and c-Cbl. Consistent with signalsome hyper-activation, roscovitine co-treatment enhanced ATRA-induced G1/0 arrest and expression of differentiation markers, CD11b, ROS and p47 Phox. Because roscovitine regulated Lyn expression, activation and partnering, a stably transfected Lyn knockdown was generated from wt-parental cells to investigate its function in ATRA-induced differentiation. Lyn-knockdown enhanced ATRA-induced up-regulation of key signalsome molecules, c-Raf, pS259-c-Raf, pS289/296/301-c-Raf, Vav1, SLP-76, and Fgr, but with essentially total loss of pY416-SFK. Compared to ATRA-treated wt-parental cells, differentiation markers p47 phox, CD11b, G1/G0 arrest and ROS production were enhanced in ATRA-treated Lyn-knockdown stable transfectants, and addition of roscovitine further enhanced these ATRA-inducible markers. The Lyn-knockdown cells expressed slightly higher c-Raf, pS259-c-Raf, pS289/296/301-c-Raf, and SLP-76 than wt-parental cells, and this was associated with enhanced ATRA-induced upregulation of Fgr and cell differentiation, consistent with heightened signaling, suggesting that enhanced Fgr may have compensated for loss of Lyn to enhance differentiation in the Lyn-knockdown cells.     

A Review on Potential Footprints of Ferulic Acid for Treatment of Neurological Disorders

Ferulic acid is being screened in preclinical settings to combat various neurological disorders. It is a naturally occurring dietary flavonoid commonly found in grains, fruits, and vegetables such as rice, wheat, oats, tomatoes, sweet corn etc., which exhibits protective effects against a number of neurological diseases such as epilepsy, depression, ischemia-reperfusion injury, Alzheimer’s disease, and Parkinson’s disease. Ferulic acid prevents and treats different neurological diseases pertaining to its potent anti-oxidative and anti-inflammatory effects, beside modulating unique neuro-signaling pathways. It stays in the bloodstream for longer periods than other dietary polyphenols and antioxidants and easily crosses blood brain barrier. The use of novel drug delivery systems such as solid-lipid nanoparticles (SLNs) or its salt forms (sodium ferulate, ethyl ferulate, and isopentyl ferulate) further enhance its bioavailability and cerebral penetration. Based on reported studies, ferulic acid appears to be a promising molecule for treatment of neurological disorders; however, more preclinical (in vitro and in vivo) mechanism-based studies should be planned and conceived followed by its testing in clinical settings.

     

Excessive Retinoic Acid Impaired Proliferation and Differentiation of Human Fetal Palatal Chondrocytes (hFPCs)

Chondrocyte proliferation and differentiation is a fundamental process during hard palatogenesis. Excessive retinoic acid (RA), the biologically most active metabolite of vitamin A, has been reported to adversely affect chondrogenesis. The aim of this study was to investigate the mechanisms underlying RA‐induced chondrocyte differentiation by using human fetal palatal chondrocytes (hFPCs) aging about 9 weeks of amenorrhea. RA treatment inhibited proliferation and induced apoptosis in hFPCs. Alkaline phosphatase activity assay, quantitative alcian blue staining, and real‐time PCR analysis revealed that RA treatment stimulated hFPCs to undergo maturation and terminal differentiation, as demonstrated by decreased chondrogenic markers and increased osteogenic markers. Further studies demonstrated that RA treatment increased Wnt/β‐catenin signaling, as demonstrated by Wnt/β‐catenin target gene expression analysis and a luciferase‐based β‐catenin–activated reporter assay. To address the role of Wnt/β‐catenin signaling, we treated hFPCs with Dickkopf‐related protein 1, an extracellular inhibitor of Wnt/β‐catenin signaling, and the observed all‐trans retinoic acid–mediated increases in nuclear accumulation of β‐catenin, alkaline phosphatase activity, and type I collagen mRNA were attenuated, suggesting that RA modulated Wnt signaling at ligand–receptor level. In summary, excessive all‐trans retinoic acid inhibited proliferation and promoted ossification of hFPCs by upregulation of Wnt/β‐catenin signaling     

All-trans retinoic acid (ATRA) induces miR-23a expression,decreases CTSC expression and granzyme B activity leading to impaired NK cell cytotoxicity

NK cell is an innate immune system lymphocyte lineage with natural cytotoxicity. Its optimal use in the clinic requires in vitro expansion and activation. Cytokines and encounter with target cells activate NK cells and induce proliferation, and this could depend on the presence of other immune cells. Here we activated PBMCs during 5 days with IL-2, with IL-2 plus the tumor cell line K562 and with the lymphoblastoid cell line R69 and perform integrated analyses of microRNA and mRNA expression profiles of purified NK cells. The samples cluster depending on the stimuli and not on the donor, indicating that the pattern of NK cell stimulation is acutely well conserved between individuals. Regulation of mRNA expression is tighter than that of miRNA expression. All stimuli induce a common preserved genetic remodeling. In addition, encounter with target cells mainly activates pathways related to metabolism. Different target cells induce different NK cell remodeling which affects cytokine response and cytotoxicity, supporting the notion that encounter with different target cells significantly changing the activation pattern. We validate our analysis by showing that activation down regulates miR-23a, which is a negative regulator of cathepsin C (CTSC) mRNA, a gene up regulated by all stimuli. The peptidase CTSC activates the granzymes, the main effector proteases involved in NK cell cytotoxicity. All-trans retinoic acid (ATRA), which induces miR-23a expression, decreases CTSC expression and granzyme B activity leading to impaired NK cell cytotoxicity in an in vivo mouse model.