大麻素受体及其Ⅰ型抑制剂的研究进展

目前已经确认的大麻素(cannabinoid,CB)受体有两种亚型:CB1和CB2,它们的分布与生理功能各不相同,其选择性抑制剂的研究也是近年来的一个热点。研究表明,CB1受体抑制剂具有良好的抗肥胖活性。本文综述了CB受体及其Ⅰ型抑制剂的研究进展。     

稳定表达大麻受体2的CHO细胞株的构建

目的建立稳定高效表达人重组大麻受体2(CB2)的中国仓鼠卵巢(CHO-K1)细胞株,为体外高通量筛选CB2激动剂和拮抗剂奠定基础。方法通过脂质体介导的方法将构建的表达载体pcDNA3.1(+)-CB2转染入CHO-K1细胞中,然后用含G418的选择性培养液进行筛选,挑取耐药克隆;培养并收集耐药克隆细胞,用RT-PCR方法做进一步筛选;序列测定鉴定整合基因的序列;筛选的阳性克隆用放射性配体-受体结合实验进行进一步的鉴定和受体活性分析。结果转染细胞在含G418的选择性培养基中生长出28个耐药单克隆,用RT-PCR方法检测出17个CB2mRNA表达量较高的阳性克隆;RT-PCR扩增片段测定鉴定正确;挑选其中最优的克隆进行放射性配体-受体结合实验,结果显示,表达受体具有与CB2激动剂WIN55212-2特异结合的活性,其Kd和Bmax值分别(1.21±0.47)nmol.L-1和(3.12±0.7)nmol.g-1蛋白,这一结果与天然CB2的特性相似。结论建立了稳定高效表达人重组CB2的CHO-K1细胞株。     

A2B型腺苷受体拮抗剂的研究进展

A_2B腺苷受体参与激活肥大细胞和炎症细胞的活性功能，选择性A_2B腺苷受体作为潜在的药物靶点正逐渐成为一个充满希望的研究热点。本文对近年来国内外有关A_2B腺苷受体拮抗剂的文献资料进行了分析和归纳。首先介绍了选择性A_2B腺苷受体拮抗剂药理学作用和开发意义；然后对选择性A_2B腺苷受体拮抗剂的开发现状、构效关系及拮抗剂与受体相互作用情况作了深入讨论；最后，对选择性A_2B腺苷受体拮抗剂研发前景进行了展望。     

哺乳动物体内大麻CB1受体分子生物学功能概述

目的探讨大麻CB1受体分子生物学功能。方法回顾大麻CB1受体相关文献。结果大麻受体CB1在CNS表达并结合Gi/o蛋白转换胞内信号,下调一系列广泛的信号机制。结论大麻CB1受体可能与神经类疾病和代谢失衡有关,选择性调节CB1受体是这类疾病首选治疗方法。     

大麻Ⅰ型受体抑制剂研究进展

临床试验表明,大麻Ⅰ型受体(CB1)抑制剂利莫那班(rimonabant)在治疗肥胖和戒烟方面具有良好效果[1],CB1受体抑制剂还具有治疗药物成瘾、认知和记忆紊乱、神经错乱等疾病的潜力。CB1受体抑制剂与诸多疾病的相关性大大推进了新的CB1受体抑制剂的发展。本文主要对各种CB1受体抑制剂的结构及活性研究的最新进展进行综述。     

选择性mGluR1拮抗剂的研究进展

代谢型谷氨酸受体1(mGluR1)作为代谢型谷氨酸受体的重要成员之一,在中枢神经系统的信号传导中起着重要作用。选择性mGluR1拮抗剂可以阻断mGluR1介导的信号通路,发挥镇痛、抗焦虑、抗抑郁等一系列生理功能。目前,选择性mGluR1拮抗剂的发现和优化成为人们研究的热点。本文对近10年选择性mGluR1拮抗剂的各类结构和构效关系进行综述。     

核磁共振技术用于脑啡吠类似物的构效关系研究

叙述利用核磁共振和计算机模拟技术研究一系列具有不同受体选择性的磁啡肽类似物的溶液构象，并据此给出分别具有δ和μ－受体活性的配体活性构象模型。     

选择性雌激素受体调节剂类乳腺癌治疗新药的研究进展

选择性雌激素受体调节剂(SERMs)是一系列结构各异的化合物，能与雌激素受体结合，依据靶组织和激素的内环境不同，表现出雌激素激动剂和(或)雌激素拮抗剂的作用，可用于治疗绝经妇女与雌激素水平有关的一系列疾病。综述治疗乳腺癌的SERMs类新药的构效关系研究与开发。     

β受体阻滞剂及其治疗高血压现状

本文主要讲述了β受体阻滞剂药理作用机制及其治疗高血压的现状,β受体阻滞剂可分为选择性与非选择性两种,选择性β受体阻滞剂是指其治疗功效在于阻滞β1亚型,避免了β 2介导作用而减少其反应.非选择β受体阻滞剂是指其治疗功效是同时非特异性的阻滞β1和β2亚型,这类药物减慢心率效果比选择性β1受体阻滞剂更为明显.值得提出的是,β受体阻滞剂对葡萄糖代谢确有影响.而选择性β1受体阻滞剂较非选择性β1受体阻滞剂对脂代谢的影响小,β1选择性越高,对脂代谢影响就越小.β受体阻滞剂治疗高血压有很强的适应证,这类药物相对副作用小,安全、价廉、有效.β受体阻滞剂的降压效果与利尿剂、Ca2 拮抗剂、ACEI、ARB、α受体阻滞剂同样有效.大多β受体阻滞剂充分作用时间在24h～48h出现,4周～8周降压效果达到理想水平,说明起效慢,但应注意不要突然停药,以免血压反跳.通常药物应从小剂量开始,治疗药物剂量及服药次数应该个体化.在控制运动状态下血压方面,优于其他类型降压药.     

抗雌激素活性化合物及其构效关系研究

抗雌激素疗法是雌激素受体依赖性乳腺癌内分泌疗法的重要手段之一。抗雌激素化合物按作用机制分类可分为选择性雌激素受体调节剂和纯抗雌激素剂,其结构类型主要包括取代雌二醇衍生物、三苯乙烯、苯骈杂环类及多酚类天然化合物。本文重点综述近年来抗雌激素化合物的作用机制、构效关系及其研究进展。     

Vascular sphingosine-1-phosphate S1P1 and S1P3 receptors

The sphingolipid sphingosine-1-phosphate (S1P) acts on five subtypes of G-protein- coupled receptors, termed S1P(1) (formerly endothelial differentiation gene-1 [Edg-1]), S1P(2) (Edg-5), S1P(3) (Edg-3), S1P(4) (Edg-6) and S1P(5) (Edg-8), and possibly several other "orphan" receptors, such as GPR3, GPR6 and GPR12. These receptors are coupled to different intracellular second messenger systems, including adenylate cyclase, phospholipase C, phosphatidylinositol 3-kinase/protein kinase Akt, mitogen-activated protein kinases, as well as Rho- and Ras-dependent pathways. Consistently with this receptor multiplicity and pleiotropic signaling mechanisms, S1P influences numerous cell functions. S1P(1)1, S1P(2) and S1P(3) receptors are the major S1P receptor subtypes in the cardiovascular system, where they mediate the effects of S1P released from platelets, and possibly other tissues (such as brain). Thus S1P(1) and S1P(3) receptors enhance endothelial and vascular smooth muscle cell proliferation and migration, playing a key role in developmental and pathological angiogenesis. In contrast, S1P(2) receptors inhibit migration of these cell types, probably because of their unique stimulatory effect on a GTPase-activating protein inhibiting the activity of Rac. S1P receptors can also cause relaxation and constriction of blood vessels. The former effect is mediated by pertussis toxin-sensitive receptors (possibly S1P(1)) located on the endothelium and stimulating phosphatidylinositol 3-kinase/Akt/endothelial nitric oxide synthase (eNOS). The vasoconstricting effect of S1P is likely to be mediated by S1P(2) and/or S1P(3) receptors, via Rho-Rho-kinase, and is more potent in coronary and cerebral blood vessels. Finally, S1P also protects endothelial cells from apoptosis through activation of phosphatidylinositol 3-kinase/Akt/eNOS via S1P(1) and S1P(3) receptors. The variety of these effects, taken together with the existence of multiple receptor subtypes, provides an abundance of therapeutic targets that currently still await the development of selective agents.     

Antimykobakterielle 1-Phenyl-1-alkylaminoalkane

Antimycobacterial 1-Phenyl-1-alkylaminoalkanes Synthesis and testing for antimycobacterial properties (M. tuberculosis H 37 Ra, Middlebrook-7H9-broth) of 1-phenyl-1-alkylaminoalkanes, which differ from antimycobacterial N-alkylbenzylamines by an additional alkyl chain in α-position, is described. By variation of both alkyl chains and introduction of one or two Cl-substituents in the aromatic ring the activity increases up to an optimum within the homologous series. Overstepping optimal lipophilicity or ramification of the alkyl chains decrease activity. Compounds 19, 20, 33-35, 51-53, 61-63, 65-67, 70-73, 96 and 102 - 104 inhibit the growth of M. tuberculosis in concentrations of 2 to 4 μg/ml.     

Sulfation of iodothyronines by human sulfotransferase 1C1 (SULT1C1)*

Sulfation is an important component of human thyroid hormone metabolism. The role of the human sulfotransferase 1C1 (SULT1C1) is not known. Because SULT1C1 is present in the adult thyroid, intra-thyroidal sulfation of thyroid hormones and their metabolites might occur. We tested this hypothesis by determining the ability of recombinant human SULT1C1 to catalyze iodothyronine sulfation. Apparent K(m) values for 3,3',5-triiodothyronine (T(3)), 3, 3'-diiodothyronine (3,3'-T(2)), 3',5',3-triiodothyronine (rT(3)), and 3,3',5,5'-tetraiodothyronine (T(4)) with SULT1C1 were 28.7, 10.3, 10.2, and 59.3 microM, respectively. Thermal stability and responses to inhibitors also were tested with T(3) as the substrate. Enzyme aliquots were measured simultaneously to determine SULT1C1 substrate preferences at optimal iodothyronine concentrations. SULT1C1 activity obtained with T(3) was used as 100%, and the activities with 3,3'-T(2), rT(3), T(4), and 3,5-diiodothyronine (3, 5-T(2)) were 614, 314, 25, and 4%, respectively. We report for the first time the characterization of human SULT1C1 with T(3) and the preferences of the enzyme for various iodothyronines. The presence of SULT1C1 in the adult thyroid gland raises the possibilities that the enzyme can contribute to intraglandular thyroid hormone processing and iodide reutilization.     

间质作用因子1通过正调控窖蛋白1抑制FBJ-S1-H的迁移性

目的证明间质作用因子(stromal interaction molecule1,Stim1)在FBJ诱导的小鼠骨肉瘤细胞中的抑癌作用。方法在Stim1高表达的FBJ-S1-H细胞采用Stim1以siRNA干扰技术得到Stim1沉默的几株S1-H单克隆细胞株,通过细胞行为学方法和RT-PCR技术对其mRNA进行研究,通过明胶酶谱法对细胞基质金属酶活性进行研究。结果通过细胞行为学方法证明,Stim1的沉默提高了细胞的迁移性,通过对mRNA表达的研究发现,Stim1沉默引起了多种基因表达的变化,其中包括基质金属酶9(matrix mexalloprotelnase 9,MMP-9)的升高,窖蛋白(caveolinl,Cav1),甾醇调控因子Srebf1的降低等,提高单克隆细胞中的Cav1含量可以使细胞迁移性降低。结论实验结果证明在FBJ-S1-H细胞中,Stim1能够抑制细胞的移动性,沉默Stim1的表达能够提高细胞的迁移性。     

Phenotype of the Cyp1a1/1a2/1b1-/- triple-knockout mouse

Crossing the Cyp1a1/1a2(-/-) double-knockout mouse with the Cyp1b1(-/-) single-knockout mouse, we generated the Cyp1a1/1a2/1b1(-/-) triple-knockout mouse. In this triple-knockout mouse, statistically significant phenotypes (with incomplete penetrance) included slower weight gain and greater risk of embryolethality before gestational day 11, hydrocephalus, hermaphroditism, and cystic ovaries. Oral benzo[a]pyrene (BaP) daily for 18 days in the Cyp1a1/1a2(-/-) produced the same degree of marked immunosuppression as seen in the Cyp1a1(-/-) mouse; we believe this reflects the absence of intestinal CYP1A1. Oral BaP-treated Cyp1a1/1a2/1b1(-/-) mice showed the same "rescued" response as that seen in the Cyp1a1/1b1(-/-) mouse; we believe this reflects the absence of CYP1B1 in immune tissues. Urinary metabolite profiles were dramatically different between untreated triple-knockout and wild-type; principal components analysis showed that the shifts in urinary metabolite patterns in oral BaP-treated triple-knockout and wild-type mice were also strikingly different. Liver microarray cDNA differential expression (comparing triple-knockout with wild-type) revealed at least 89 genes up- and 62 genes down-regulated (P-value < or = 0.00086). Gene Ontology "classes of genes" most perturbed in the untreated triple-knockout (compared with wild-type) include lipid, steroid, and cholesterol biosynthesis and metabolism; nucleosome and chromatin assembly; carboxylic and organic acid metabolism; metal-ion binding; and ion homeostasis. In the triple-knockout compared with the wild-type mice, response to zymosan-induced peritonitis was strikingly exaggerated, which may well reflect down-regulation of Socs2 expression. If a single common molecular pathway is responsible for all of these phenotypes, we suggest that functional effects of the loss of all three Cyp1 genes could be explained by perturbations in CYP1-mediated eicosanoid production, catabolism and activities.     

Substrate-dependent modulation of UDP-glucuronosyltransferase 1A1 (UGT1A1) by propofol in recombinant human UGT1A1 and human liver microsomes

Our previous study has shown that propofol, a probe substrate for human UDP-glucuronosyltransferase (UGT) 1A9, activated the glucuronidation of 4-methylumbelliferone (4-MU) by recombinant UGT1A1 in a concentration-dependent manner. In the present study, we investigated the mechanism of activation, and whether the stimulatory effect occurs when another substrate is used with human liver microsomes. The glucuronidation of 4-MU followed Michaelis-Menten kinetics with a K(m) value of 101 microM in the absence of propofol. In the presence of 200 microM propofol, a concentration that causes heterotopic activation of 4-MU glucuronidation (4-MUG), the V(max) value increased to 1.5-fold, while the K(m) value decreased to 0.53-fold. In order to assess whether propofol activates UGT1A1 activity for a substrate other than 4-MU, the effect of propofol on oestradiol 3beta-glucuronidation by recombinant UGT1A1 and in human liver microsomes was evaluated. In contrast to 4-MUG activity, propofol inhibited UGT1A1-catalysed oestradiol 3beta-glucuronidation in recombinant UGT1A1 as well as in human liver microsomes with IC(50) values of 59 and 228 microM, respectively. In addition, a known UGT1A1 modulator, 17alpha-ethynyloestradiol, stimulated oestradiol 3beta-glucuronidation slightly at a concentration of 5 microM, while it inhibited 4-MUG in recombinant UGT1A1 at all concentrations tested (5-100 microM). These findings indicate that the modulation of UGT1A1 by propofol is substrate-dependent, and thus care should be taken when extrapolating the stimulatory effects of drugs for one glucuronidation substrate.