Sphingosine 1-phosphate (S1P)/S1P receptor 1 signaling regulates receptor activator of NF-κB ligand (RANKL) expression in rheumatoid arthritis

Sphingosine 1-phosphate (S1P)/S1P receptor 1 (S1P1) signaling plays an important role in synovial cell proliferation and inflammatory gene expression by rheumatoid arthritis (RA) synoviocytes. The purpose of this study is to clarify the role of S1P/S1P1 signaling in the expression of receptor activator of NF-κB ligand (RANKL) in RA synoviocytes and CD4(+) T cells. We demonstrated MH7A cells, a human RA synovial cell line, and CD4(+) T cells expressed S1P1 and RANKL. Surprisingly, S1P increased RANKL expression in MH7A cells and CD4(+) T cells in a dose-dependent manner. Moreover, S1P enhanced RANKL expression induced by stimulation with TNF-α in MH7A cells and CD4(+) T cells. These effects of S1P in MH7A cells were inhibited by pretreatment with PTX, a specific Gi/Go inhibitor. These findings suggest that S1P/S1P1 signaling may play an important role in RANKL expression by MH7A cells and CD4(+) T cells. S1P/S1P1 signaling of RA synoviocytes is closely connected with synovial hyperplasia, inflammation, and RANKL-induced osteoclastogenesis in RA. Thus, regulation of S1P/S1P1 signaling may become a novel therapeutic target for RA.     

植物体内的鞘氨醇-1-磷酸(S1P)

鞘氨醇-1-磷酸（S1P）在植物体内也可作为一种信号分子参与ABA介导的保卫细胞信号转导过程,这一途径和异三聚体G蛋白相耦联。文章对此问题的研究进展作了介绍。     

Blocking S1P interaction with S1P₁ receptor by a novel competitive S1P₁-selective antagonist inhibits angiogenesis

Sphingosine 1-phosphate receptor type 1 (S1P(1)) was shown to be essential for vascular maturation during embryonic development and it has been demonstrated that substantial crosstalk exists between S1P(1) and other pro-angiogenic growth factors, such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor. We developed a novel S1P(1)-selective antagonist, TASP0277308, which is structurally unrelated to S1P as well as previously described S1P(1) antagonists. TASP0277308 inhibited S1P- as well as VEGF-induced cellular responses, including migration and proliferation of human umbilical vein endothelial cells. Furthermore, TASP0277308 effectively blocked a VEGF-induced tube formation in vitro and significantly suppressed tumor cell-induced angiogenesis in vivo. These findings revealed that S1P(1) is a critical component of VEGF-related angiogenic responses and also provide evidence for the efficacy of TASP0277308 for anti-cancer therapies.     

Discovery of thiadiazole amides as potent, S1P₃-sparing agonists of sphingosine-1-phosphate 1 (S1P₁) receptor

High-throughput screening of GSK compound collection led to the discovery of a novel series of thiadiazole amides as potent and S1P(3)-sparing sphingosine-1-phosphate 1 (S1P(1)) receptor agonists. Synthesis, structure and activity relationship, selectivity, and some developability properties are described.     

Actions of a picomolar short-acting S1P₁ agonist in S1P₁-eGFP knock-in mice

Sphingosine 1-phosphate receptor 1 (S1P(1)) is critical for lymphocyte recirculation and is a clinical target for treatment of multiple sclerosis. By generating a short-duration S1P(1) agonist and mice in which fluorescently tagged S1P(1) replaces wild-type receptor, we elucidate physiological and agonist-perturbed changes in expression of S1P(1) at a subcellular level in vivo. We demonstrate differential downregulation of S1P(1) on lymphocytes and endothelia after agonist treatment.     

谷胱甘肽S－转移酶基因P1的研究进展

谷胱甘肽S－转移酶P1－1在癌变细胞和抗药性肿瘤细胞中表达水平发生变化,提示可以作为恶性转化及肿瘤抗药性的标志物．对大鼠谷胱甘肽S－转移酶P1基因上游调控序列的研究发现在－2.5kb及－2.2kb各存在一增强子序列GPEⅠ,GPEⅡ,－400bP存在一沉寂子．GPEⅠ、沉寂子上均至少结合有3种反式作用因子．人谷胱甘肽S－转移酶P1基因上游区域中迄今尚未发现增强子或沉寂子,但却发现了胰岛素及视黄酸的应答序列,在癌变细胞和抗药性的肿瘤细胞中该基因表达的调控机制有别于正常细胞．     

S1P对心肌细胞的保护作用研究

目的：探究1-磷酸鞘氨醇（S1P）对缺氧／复氧乳鼠心肌细胞的保护作用及其分子机制。方法：在大鼠乳鼠心肌细胞原代培养基础上,应用液体石蜡覆盖法制备心肌细胞缺氧／复氧模型,采用流式细胞术PI染色法和流式细胞术罗丹明123染色法检测S1P对缺氧／复氧心肌细胞的细胞凋亡和线粒体膜电位的影响;Western Blot分析法检测S1P作用后的心肌细胞p-Akt1蛋白水平变化,并且观察PI3K（磷脂酰肌醇3-激酶）阻断剂渥曼青霉素（wommamin）对S1P上述作用的影响。结果：在S1P的影响下,缺氧／复氧心肌细胞的凋亡率显著下降（P〈0．01）,线粒体膜电位的去极化被明显抑制（P〈0．05）,p-Akt1水平明显升高（P〈0．01）,wormannin能够部分阻断S1P的上述效应。结论：S1P能够显著抑制缺氧／复氧引起的心肌细胞凋亡,其机制可能与S1P激活PDK-Akt信号通路进而稳定线粒体膜电位有关。     

The NOXO1β PX domain preferentially targets PtdIns(4,5)P2 and PtdIns(3,4,5)P3

NOXO1β [NOXO1 (Nox organizer 1) β] is a cytosolic protein that, in conjunction with NOXA1 (Nox activator 1), regulates generation of reactive oxygen species by the NADPH oxidase 1 (Nox1) enzyme complex. NOXO1β is targeted to membranes through an N-terminal PX (phox homology) domain. We have used NMR spectroscopy to solve the structure of the NOXO1β PX domain and surface plasmon resonance (SPR) to assess phospholipid specificity. The solution structure of the NOXO1β PX domain shows greatest similarity to that of the phosphatidylinositol 3-kinase-C2α PX domain with regard to the positions and types of residues that are predicted to interact with phosphatidylinositol phosphate (PtdInsP) head groups. SPR experiments identify PtdIns(4,5)P(2) and PtdIns(3,4,5)P(3) as preferred targets of NOXO1β PX. These findings contrast with previous lipid overlay experiments showing strongest binding to monophosphorylated PtdInsP and phosphatidylserine. Our data suggest that localized membrane accumulation of PtdIns(4,5)P(2) or PtdIns(3,4,5)P(2) may serve to recruit NOXO1β and activate Nox1.     

1-磷酸鞘氨醇(S1P)对H9c2心肌细胞肥大反应的保护作用

目的:研究1-磷酸鞘氨醇(S1P)对H9c2心肌细胞肥大反应的影响。方法:将培养的H9c2心肌细胞随机分为4组,即正常对照组、S1P(1μmol/L)处理组、苯肾上腺素(PE,100μmol/L)处理组、PE(100μmol/L)加S1P(1μmol/L)处理组,每组设3个复孔。处理24 h后应用Actin-Trakcer Green免疫荧光染色检测各组心肌细胞形态大小;Real-Time PCR技术测定各组H9c2心肌细胞中肥大标志物ANP、BNP及β-MHC的转录水平;Western印迹法测定各组中ANP的蛋白表达情况。然后将H9c2心肌细胞随机分为5组,即正常对照组、PE(100μmol/L)组、PE(100μmol/L)加低浓度S1P(0.1μmol/L)组、PE加中浓度S1P(1μmol/L)组、PE加高浓度S1P(10μmol/L)组,每组设3个复孔。处理24 h后应用Western印迹法测定低、中、高浓度S1P干预下磷酸化的Janus激酶2(JAK2)及信号转导和转录激活子3(STAT3)的蛋白表达水平。每项试验独立重复三次。结果:与正常对照组比较,PE组的H9c2心肌细...     

烟叶蛋白(F─1─P)功能特性

烟叶蛋白（Ｆ─１─Ｐ）功能特性储植摘译（海安县韩洋中学）烟草（ＮｉｃｏｔｉａｎａｔａｋａｃｕｍＬ）栽培种Ｎｃ９５，直播，密度约５０００００株／ｈａ，长至６０ｃｍ高时，收获其生物产量并制取Ｆ─１─Ｐ晶体。这种蛋白质，或者是结晶悬浮液，或者是ｐＨ８．５溶...     

MSC与S1P联用对急性损伤的肺内皮细胞中S1P代谢相关酶的表达调控

目的:探究间充质干细胞(MSC)与鞘氨醇-1-磷酸(S1P)联用对急性肺损伤发生过程中S1P代谢相关酶的表达调控作用。方法:构建脂多糖(LPS)刺激的急性损伤的肺内皮细胞模型,与MSC及S1P非接触共培养后,利用细胞实时无标记系统,考察MSC与S1P联用对损伤细胞微电子阻抗的增强保护作用,利用RT-PCR考察两者对损伤细胞中S1P代谢相关酶的表达调控作用。结果:MSC与S1P联用与单独使用时相比,作用靶点和效果有显著差别,MSC单独使用时仅下调鞘氨醇激酶1(Sph K1)、S1P裂解酶(S1PL)和鞘磷脂合成酶1(SMS1)的表达,但当将MSC和S1P联合使用时,其对S1PL的下调作用丧失,而鞘氨醇激酶2(Sph K2)和鞘磷脂合成酶2(SMS2)的表达明显下调。结论:MSC作为一种潜在的治疗手段,可以同时作用于多个S1P代谢相关基因,而且其与S1P的联用对相关基因的表达调控并不是简单的作用叠加,而是表现出更为显著的治疗结果。本研究为进一步探讨MSC与S1P联用,通过改善内皮屏障的生物学功能对急性肺损伤的治疗作用及可能的协同机理奠定了实验基础。     

Discovery, design and synthesis of novel potent and selective sphingosine-1-phosphate 4 receptor (S1P₄-R) agonists

High affinity and selective small molecule agonists of the S1P(4) receptor (S1P(4)-R) may have significant therapeutic utility in diverse disease areas including autoimmune diseases, viral infections and thrombocytopenia. A high-throughput screening (HTS) of the Molecular Libraries-Small Molecule Repository library identified 3-(2-(2,4-dichlorophenoxy)ethoxy)-6-methyl-2-nitropyridine as a moderately potent and selective S1P(4)-R hit agonist. Design, synthesis and systematic structure-activity relationships study of the HTS-derived hit led to the development of novel potent S1P(4)-R agonists exquisitely selective over the remaining S1P(1-3,5)-Rs family members. Remarkably, the molecules herein reported provide novel pharmacological tools to decipher the biological function and assess the therapeutic utility of the S1P(4)-R.     

Synthesis of (S)-(—)-Vertinolide

(S)-(?)-Vertinolide 1 was synthesized via the tetronic acid derivative 6 from (S)-(?)-tetrahydro-2-methyl-5-oxo-2-furancarboxylic acid 3. (±)-Vertinolide was also synthesized from (±)-3.     

Enzymatic Deamination of (±)-2-Methyl- and (S)-2,2-Dimethyl-1-aminocyclopropane-1-carboxylic Acid

The effects of drinking deaerated water on serum biochemical values, and on the concentrations of short-chain fatty acids (SCFAs) derived from bacterial fermentation in the colon were examined in rats. Drinking deaearted water decreased the levels of serum alkaline phosphatase (SAP) and serum urea nitrogen (SUN), and increased the serum potassium (SK) and serum phosphorus (SP) levels. Although the concentration of propionic acid in the cecum was decreased by drinking deaerated water, the concentrations of isobutyric, valeric, and isovaleric acids in the cecum were increased.     

SAR analysis of innovative selective small molecule antagonists of sphingosine-1-phosphate 4 (S1P₄) receptor

Recent evidence suggests an innovative application of chemical modulators targeting the S1P(4) receptor as novel mechanism-based drugs for the treatment of influenza virus infection. Modulation of the S1P(4) receptor may also represent an alternative therapeutic approach for clinical conditions where reactive thrombocytosis is an undesired effect or increased megakaryopoiesis is required. With the exception of our recent research program disclosure, we are not aware of any selective S1P(4) antagonists reported in the literature to date. Herein, we describe complementary structure-activity relationships (SAR) of the high-throughput screening (HTS)-derived hit 5-(2,5-dichlorophenyl)-N-(2,6-dimethylphenyl)furan-2-carboxamide and its 2,5-dimethylphenyl analog. Systematic structural modifications of the furan ring showed that both steric and electronic factors in this region have a significant impact on the potency. The furan moiety was successfully replaced with a thiophene or phenyl ring maintaining potency in the low nanomolar range and high selectivity against the other S1P receptor subtypes. By expanding the molecular diversity within the hit-derived class, our SAR study provides innovative small molecule potent and selective S1P(4) antagonists suitable for in vivo pharmacological validation of the target receptor.