低副作用的大麻类镇痛药物研究：内源肽类激动剂的鉴定和药物联用新策略

发布时间：2018-02-05 01:29

本文关键词： (m)VD-Hpα NPFF NPVF WIN55 212-2 镇痛耐受中枢副作用　出处：《兰州大学》2014年博士论文　论文类型：学位论文

【摘要】：疼痛是人类所经受的最常见的症状之一,传统的镇痛药物由于存在不同程度的不良反应,导致其在临床应用中具有很大的局限性。近年来,大量的研究表明大麻类药物在高效、低副作用的新型镇痛药物的研发方面具有广泛的应用前景。但是,大麻作为镇痛药物使用时仍需克服一些中枢副作用,如抑制运动、便秘、降低体温、药物耐受及成瘾等。本论文中主要探讨了两种降低大麻类镇痛药物副作用的新途径:1)系统地评价了新型大麻肽类激动剂的镇痛活性及其中枢副作用,以期为新型肽类大麻镇痛药物的研究提供全新的化学模板分子;2)基于大麻和神经肽FF (NPFF)系统相互作用的研究,探讨了大麻与NPFF系统的配体联用介导低副作用的镇痛活性的新策略。近年来,研究人员利用分子的不同特性构建的新型大麻配体分子,有效地降低或减少了大麻类药物的一些副作用。最近,在机体内又发现了一类内源性大麻肽类配体,其分子理化性质和药代动力学特性不同于传统的大麻类配体,在体外实验中表现为大麻样激动活性,系统地鉴定该类激动剂的镇痛作用及中枢活性,有望为低副作用的大麻类镇痛药物的设计和发现提供全新的化学模板分子。因此,本文系统地评价了源于小鼠血红蛋白α链的CB1受体新型肽类激动剂(m)VD-Hpα的在体活性。在小鼠光热甩尾实验中,脊髓以上及脊髓水平注射的(m)VD-Hpα均表现出较强的镇痛活性,其镇痛EC50值分别为6.69和2.88 nmol。受体拮抗实验结果表明,(m)VD-Hpα在中枢引起的镇痛作用是CB1受体介导的。此外,侧脑室注射的(m)VD-Hpα只有在较高的有效镇痛剂量下才表现出降低体温和抑制运动的活性,但在高剂量时对胃肠运动也无显著的调节作用。另外,(m)VD-Hpα并不诱导奖赏作用;虽然,在较高的有效镇痛剂量(2×EC50和3×EC50)下,(m)VD-Hpα也会产生镇痛耐受,但其耐受程度要低于传统大麻激动剂WIN55,212-2的。此外,中枢注射的(m)VD-Hpα还能诱导增强摄食的作用。因此,与传统的大麻激动剂相比,大麻肽类激动剂(m)VD-Hpα在中枢能介导显著的镇痛活性且伴随较少的中枢副作用。在药物联用策略中,大量的报道指出大麻与阿片等其它药物联用能有效降低大麻镇痛药物的给药剂量,从而降低或避免其副作用的产生。本研究系统地探讨了 NPFF与大麻系统之间的相互作用,并基于此研究提出了 NPFF与大麻系统的配体联合给药的新策略。本文的研究结果表明,NPFF及相关肽能通过自身受体对大麻受体非选择性激动剂WIIN55,212-2的中枢(CB1受体介导)和外周((B2受体介导)镇痛表现出显著的调节作用。侧脑室注射的NPFF受体非选择性激动剂NPFF能显著减弱WIN55,212-2的中枢和外周镇痛,而NPFF1和NPFF2受体选择性激动剂NPVF和dNPA则增强了大麻的中枢和外周镇痛,且NPVF的增强效果更显著。基于以上NPVF对WIN55,212-2中枢镇痛的增强作用,本文进一步评价了NPVF与WIN55,212-2联用的新策略介导的镇痛和中枢副作用。在小鼠光热甩尾实验中,WIN55,212-2和NPVF联合注射引起的镇痛显著强WIN55,212-2单独的作用,镇痛EC50值从大麻单独的3.51 nmol降低到与NPVF联合注射的0.69 nmol。而且,3 nmol WIN55,212-2 和 30 nmol NPVF 联用与 9 nmol WIN55,212-2 诱导相当程度的镇痛作用。进一步的受体拮抗实验表明,WIN55,212-2的中枢镇痛是通过CB1受体介导的。同时,NPVF增强CB1受体介导的大麻中枢镇痛是通过特异性激活NPFF受体实现的。虽然,3 nmol WIN55,212-2与NPVF联用也会引起与9nmolWIN55,212-2相当的降低体温和抑制运动的作用,但是,联合注射对胃肠运动的抑制显著减少,尤其是联合注射能介导无耐受的镇痛作用。这些数据表明,由大麻CB1和NPFF受体共同介导的WIN55,212-2与NPVF联合产生的增强的镇痛伴随的副作用要显著小于高剂量WIN55,212-2介导的,且两种药物的联用能避免高剂量大麻镇痛耐受的出现。综上所述,本文通过一系列的在体实验探讨了降低大麻镇痛药物副作用的两种新策略:1)大麻CB1受体的内源性肽类激动剂(m)VD-Hpα能介导高效的镇痛活性,且只有在较高的镇痛剂量下才表现出抑制运动、降低体温和镇痛耐受等中枢副作用。另外,(m)VD-Hpα在高的镇痛剂量下也未表现出抑制胃肠运动和奖赏的作用。因此,该肽类大麻激动剂可以作为新的有价值的先导化合物,通过进一步结构改造构建低副作用的大麻类镇痛新药;2)大麻激动剂和NPVF联用的新策略有效地降低了大麻镇痛药物的剂量,从而减少或减弱了大麻的部分中枢副作用。因此,本文通过对新的大麻配体镇痛活性的鉴定和药物联用的研究为高效、低副作用的大麻类镇痛药物的研发提供了新的思路和理论依据。
[Abstract]:Pain is one of the most common symptoms of human experience, the traditional analgesic drug adverse reactions due to different degree, which has great limitations in clinical application. In recent years, a large number of studies show that cannabis drugs in high efficiency, and has wide application prospect research new analgesic low side effect.. however, when using marijuana as analgesic drugs still need to overcome some central side effects, such as inhibiting movement, constipation, hypothermia, drug tolerance and addiction. This thesis mainly discusses two kinds of new ways to reduce the side effects of cannabis analgesic drugs: 1) the systematic evaluation of the model peptide agonist of marijuana the central analgesic activity and side effects, in order to provide a new molecular chemical template for the study of novel peptide marijuana analgesic drugs; 2) marijuana and neuropeptide FF (NPFF) based on the interaction of the system, study A new strategy of ligand marijuana and NPFF system mediated analgesic activity associated with low side effects. In recent years, new hemp ligands construct different researchers using molecular characteristics, effectively reduce or reduce the side effects of cannabis drugs. Recently, a class of endogenous peptide ligands found in marijuana the body, physicochemical and pharmacokinetic properties of the ligand molecule is different from the traditional hemp, in vitro experiments for marijuana like agonist activity, system identification of the agonist analgesia and central activity, is expected to provide a new chemical template molecule for design and discovery of cannabinoid analgesic drugs with fewer side effects the CB1 receptor model. Therefore, this paper systematically evaluates the peptide derived from mouse Hemoglobin alpha chain agonist (m) VD-Hp alpha activity in vivo. In the mouse tail flick experiments, above the spinal cord and spinal cord The level of injection (m) VD-Hp alpha showed strong analgesic activity, its analgesic EC50 values were 6.69 and 2.88 nmol. receptor antagonist (m). The experimental results show that the analgesic effect of VD-Hp alpha in the central nervous system is mediated by the CB1 receptor. In addition, the intracerebroventricular injection of VD-Hp alpha (m) only in the effective under higher analgesic doses showed lower body temperature and inhibit the movement of the activity, but at high doses on gastrointestinal motility has no significant moderating effect. In addition, VD-Hp alpha (m) did not induce reward effect; although, in high effective analgesic dose (2 * EC50 and 3 * EC50 (M). VD-Hp alpha) will produce analgesic tolerance, but the tolerance level is lower than the traditional cannabis agonist WIN55212-2. In addition, the central administration of (m) VD-Hp alpha can induce enhanced feeding effect. Therefore, with the traditional cannabis agonist than cannabis peptide agonists (m) in the central VD-Hp alpha mediates significant analgesia The activity with fewer side effects. In the central drug combination strategy, a large number of reports of marijuana and other drugs associated with opioid analgesic marijuana can effectively reduce drug dosage, so as to reduce or avoid its side effects. This paper studies the interaction between NPFF and Ma system based on this research, and put forward the ligand NPFF and system for the new strategy combined with marijuana drug. The results of this study indicate that central NPFF and related peptides can through their receptors on non cannabinoid receptor selective agonist WIIN55212-2 (CB1 receptor) and peripheral ((B2 receptor) showed analgesic significant role. Intracerebroventricular injection of non selective NPFF receptor agonist NPFF WIN55212-2 can significantly reduced the central and peripheral analgesia, while NPFF1 and NPFF2 receptor selective agonist NPVF and dNPA can enhance the central hemp And peripheral analgesia, and the enhancement effect is more significant. NPVF enhancement of WIN55212-2 central analgesia based on the above NPVF, this paper further evaluates the new strategy of NPVF mediated by WIN55212-2 with analgesic and central side effects. In the mouse tail flick experiments, WIN55212-2 and NPVF combined injection induced analgesia was significantly stronger WIN55212-2 separate effect, analgesic EC50 value from 3.51 nmol down to marijuana alone and combined with injection of NPVF 0.69 nmol., with a considerable degree of analgesic effect induced by 9 nmol WIN55212-2 with 3 nmol WIN55212-2 and 30 nmol NPVF. Further experiments showed that the receptor antagonist WIN55212-2, central analgesia is mediated by the CB1 receptor. NPVF, enhanced CB1 receptor mediated by hemp central analgesia specific activation of NPFF receptor. Although the causes and 9nmolWIN5 combined with 3 nmol WIN55212-2 and NPVF 5212-2 a lower body temperature and inhibit the movement of the role, however, inhibition of combined injection on gastrointestinal motility was significantly reduced, especially the combined injection can mediate analgesia without tolerance. These data suggest that the side effects associated with WIN55212-2 and NPVF by CB1 and NPFF receptor of marijuana mediated enhancement combined to produce analgesia to the high dose was significantly less than that mediated by WIN55212-2, and the two drug combination can avoid high doses of marijuana analgesic tolerance. To sum up, through a series of experiments in vivo to explore two new strategies to reduce the side effects of cannabis analgesic drugs: 1) endogenous cannabinoid CB1 receptor agonist peptide (m) VD-Hp alpha mediated analgesic activity, and only in the condition of high analgesic doses showed inhibition of movement, hypothermia and analgesic tolerance of central side effects. In addition, (m) VD-Hp in high dose analgesia That did not show inhibition of gastrointestinal movement and reward effect. Therefore, the peptide agonist of marijuana can be used as lead compounds of new value, through further structural modification of constructing new analgesic cannabis low side effect; 2) the new strategy of cannabis agonist combined with NPVF can effectively reduce the analgesic dose of marijuana thus, to reduce or weaken the marijuana part of central side effects. Therefore, this paper through the identification and drug of marijuana ligand analgesic activity associated with the new efficient, provide new ideas and theoretical basis for development of cannabinoid analgesic drugs with fewer side effects.

【学位授予单位】：兰州大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R971

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