藍(lán)瑞芳 李 崢
廣西壯族自治區(qū)欽州市第一人民醫(yī)院神經(jīng)內(nèi)科,廣西欽州535000
白藜蘆醇在癲癇治療中的研究進(jìn)展
藍(lán)瑞芳 李 崢
廣西壯族自治區(qū)欽州市第一人民醫(yī)院神經(jīng)內(nèi)科,廣西欽州535000
癲癇是慢性反復(fù)發(fā)作性疾病,有20%~30%的癲癇患者經(jīng)正規(guī)的抗癲癇治療后癲癇發(fā)作仍不能得到有效控制。癲癇的發(fā)病機(jī)制復(fù)雜,目前的抗癲癇藥物均有一定的不足之處或副作用較大。白藜蘆醇是一種多效的植物抗毒素,對(duì)癲癇具有一定的治療作用。其抗癲癇的機(jī)制包括了抑制異常放電、減輕癲癇發(fā)作后炎性反應(yīng),對(duì)抗癲癇發(fā)作誘導(dǎo)的細(xì)胞凋亡及神經(jīng)元的保護(hù)作用。
癲癇;白藜蘆醇;異常放電;炎性反應(yīng)
癲癇是神經(jīng)系統(tǒng)常見(jiàn)疾病,由腦血管疾病、器質(zhì)性病變、感染性疾病、遺傳等多病因引起的綜合征,全世界癲癇患病率為1%,約有5000萬(wàn)例癲癇患者[1-2]。長(zhǎng)期反復(fù)的癲癇發(fā)作不僅使患者軀體受到損害,而且在一定程度上可導(dǎo)致患者心理障礙及一系列的社會(huì)問(wèn)題??拱d癇藥物如卡馬西平、丙戊酸等可有效地控制部分癲癇患者,但仍有20%~30%的患者經(jīng)正規(guī)的抗癲癇治療后發(fā)作不能得到有效控制,成為難治性癲癇。另外一方面,由于目前現(xiàn)有的抗癲癇藥物均有副作用,且藥理及藥力動(dòng)力學(xué)上存在一定的不足,因此臨床上一直在找尋一種新型的抗癲癇藥物。白黎蘆醇(resveratrol,Res)是一種天然多酚類,廣泛存在于葡萄皮、虎杖等多種植物中。Res具有抗氧化、清除氧自由基、抗癲癇等多種生理活性[3]。在其眾多生物與藥理活性作用中,目前越來(lái)越引起人們關(guān)注的是Res抗癲癇作用[4],已成為新的研究熱點(diǎn)。本文就Res來(lái)源和體內(nèi)代謝過(guò)程、抗癲癇及神經(jīng)保護(hù)作用及臨床應(yīng)用所面臨的問(wèn)題作一綜述。
Res的化學(xué)名稱為3,5,4-三羥基二苯乙烯,是一種植物抗毒素,其結(jié)構(gòu)為一種多酚化合物,廣泛存在于葡萄皮、虎杖等植物中。天然存在的Res有反式和順式兩種同分異構(gòu)體,其中以反式結(jié)構(gòu)較為穩(wěn)定,生物活性更好[5-6]。在人體內(nèi)主要以白藜蘆醇苷的形式存在。Res可以先與葡萄糖結(jié)合,生成相應(yīng)的苷類,在腸道中糖苷酶的作用下可以釋放出Res而發(fā)揮藥理學(xué)活性。體外研究顯示50%~98%的Res可與白蛋白、低密度脂蛋白及血紅蛋白結(jié)合[7-8]。在人類大約50%的Res代謝產(chǎn)物通過(guò)結(jié)合蛋白轉(zhuǎn)運(yùn);70%~98%的Res在24 h內(nèi)在腎臟被代謝掉[9]。
2.1 Res抑制異常放電
癲癇發(fā)作由神經(jīng)元細(xì)胞發(fā)生異常放電所致,神經(jīng)元異常放電的確切機(jī)制至今尚未完全闡明。目前有癲癇病理學(xué)研究發(fā)現(xiàn),癲癇最明顯的病理學(xué)特征是海馬苔蘚纖維發(fā)芽(mossy fiber sprouting,MFS),有實(shí)驗(yàn)表明,海馬CA1區(qū)神經(jīng)元大量丟失,使其下位突觸空缺,誘導(dǎo)存活神經(jīng)元異常芽生,從而參與MFS生長(zhǎng),引起神經(jīng)元網(wǎng)絡(luò)重組,改變癇樣放電的方向和傳播途徑,避開(kāi)一些抗癲癇藥物作用的重要靶點(diǎn),導(dǎo)致難治性癲癇的形成[10-11]。目前有研究發(fā)現(xiàn)Res可明顯地抑制MFS,降低了海馬內(nèi)神經(jīng)元同步化放電和癲癇自發(fā)發(fā)作的頻率,具有較好的抗癲癇作用[12]。尤竹燕等[13]通過(guò)正常大鼠海馬腦片灌流γ-氨基丁酸受體拮抗劑引起癲癇樣活動(dòng)以及在正常大鼠海馬CA1區(qū)注射海人藻酸建立顳葉癲癇大鼠模型,應(yīng)用離體腦片細(xì)胞外場(chǎng)電位記錄,發(fā)現(xiàn)隨著Res灌流濃度增加到50 μmol/L,可部分抑制兩者誘發(fā)的癲癇樣活動(dòng),并指出Res抑制異常放電的可能機(jī)制為通過(guò)調(diào)節(jié)N-甲基-D-天冬氨酸受體的功能抑制海馬CA1區(qū)的癲癇放電。目前有研究指出中樞神經(jīng)系統(tǒng)內(nèi)興奮性和抑制性氨基酸比例的失衡可能是導(dǎo)致癲癇發(fā)作的直接原因[14],李敏等[15]發(fā)現(xiàn)低劑量Res對(duì)慢性癲癇大鼠海馬谷氨酸(Glu)/γ-氨基丁酸(GABA)比值失衡具有明顯保護(hù)作用,但對(duì)皮層Glu/GABA比值失衡沒(méi)有明顯保護(hù)作用。
2.2 Res與癲癇發(fā)作后的細(xì)胞凋亡
細(xì)胞凋亡是一種特殊的細(xì)胞死亡類型,其受生理及病理誘導(dǎo)而發(fā)生,該過(guò)程包括細(xì)胞內(nèi)信號(hào)系統(tǒng)的激活,相應(yīng)凋亡程序的啟動(dòng),最終實(shí)現(xiàn)細(xì)胞的自我破壞、自我死亡。反復(fù)和長(zhǎng)期的癲癇發(fā)作易導(dǎo)致大腦尤其是海馬區(qū)神經(jīng)元的發(fā)生壞死和凋亡[16-17]。不少臨床及動(dòng)物模型證明了癲癇發(fā)作繼而發(fā)生海馬硬化、神經(jīng)細(xì)胞變性,都可直接導(dǎo)致大腦海馬萎縮,這種體積的改變是神經(jīng)細(xì)胞凋亡的結(jié)果。凋亡是一個(gè)精細(xì)調(diào)控過(guò)程,其中包括了不同基因表達(dá)的改變。其中Bax和Bcl-2是調(diào)控細(xì)胞凋亡的重要基因,Bcl-2是抗凋亡基因Bcl-2家族中的重要成員,其在調(diào)控細(xì)胞線粒體介導(dǎo)的凋亡中發(fā)揮著重要的作用。Bcl-2的高表達(dá)對(duì)神經(jīng)細(xì)胞有一定的保護(hù)作用[18]。另外一方面Bax可以促進(jìn)細(xì)胞凋亡的發(fā)生,其具體機(jī)制可能與破壞線粒體膜及促進(jìn)細(xì)胞色素C釋放有關(guān)[19]。當(dāng)細(xì)胞凋亡發(fā)生時(shí),細(xì)胞內(nèi)Bax和Bcl-2的比率升高[20-21]。郭家智等[22]發(fā)現(xiàn),經(jīng)Res預(yù)處理的癲癇大鼠海馬內(nèi)抗凋亡Bcl-2表達(dá)及Bcl-2陽(yáng)性細(xì)胞量均增加。促凋亡因子Caspase-3和Bax表達(dá)被抑制,Caspase-3和Bax陽(yáng)性細(xì)胞總量減少,提示了Res可抑制癲癇大鼠海馬凋亡相關(guān)蛋白的表達(dá),對(duì)抗癲癇發(fā)作所誘導(dǎo)的細(xì)胞凋亡過(guò)程。
2.3 Res減少癲癇發(fā)作后炎性反應(yīng)
目前大量的實(shí)驗(yàn)和臨床研究證實(shí)炎性反應(yīng)在癲癇的發(fā)生和發(fā)展中起重要的作用[23-25]。癲癇發(fā)作后的炎性反應(yīng)提高了神經(jīng)元興奮性,繼而進(jìn)一步損傷仍存活的神經(jīng)元細(xì)胞。有研究顯示癲癇能激活雷帕霉素哺乳動(dòng)物靶點(diǎn)(mammalian target of rapamycin,mTOR),提高核轉(zhuǎn)錄因子kappa B(nuclear transcription factorkappa B,NF-κB)活性,促進(jìn)炎癥因子一氧化氮合酶、環(huán)氧合酶-2等的表達(dá),從而發(fā)揮抗癲癇作用[26]。
2.4 Res與癲癇發(fā)作后神經(jīng)元保護(hù)作用
除了抑制癲癇發(fā)作的異常放電,Res具有神經(jīng)元的保護(hù)作用也是其治療癲癇的理想方法[27]。而近年來(lái)針對(duì)神經(jīng)退行性疾病、腦損傷實(shí)驗(yàn)研究均提示Res具有神經(jīng)元保護(hù)作用[28-29],且對(duì)正常大腦具有維護(hù)線粒體功能、神經(jīng)保護(hù)的活性[30]。目前已有大量的臨床研究證實(shí)了癲癇反復(fù)發(fā)作可導(dǎo)致認(rèn)知功能障礙。近期研究發(fā)現(xiàn)Res對(duì)戊四氮致癇大鼠同時(shí)具有抗癲癇和改善其空間學(xué)習(xí)記憶能力的兩重作用,與其保護(hù)神經(jīng)元的作用有關(guān),但具體作用機(jī)制尚不明確[31]。
綜上所述,Res通過(guò)抑制異常放電、抗凋亡、抗炎以及神經(jīng)元保護(hù)作用等多個(gè)途徑來(lái)實(shí)現(xiàn)治療癲癇。但目前的研究多局限于動(dòng)物實(shí)驗(yàn)和細(xì)胞實(shí)驗(yàn),臨床應(yīng)用的研究報(bào)道較少,而對(duì)于其臨床應(yīng)用安全性、有效性的研究目前未見(jiàn)有報(bào)道。在今后的工作中,研究重點(diǎn)應(yīng)當(dāng)逐步轉(zhuǎn)移到人體內(nèi)的機(jī)制研究、臨床試驗(yàn)以及安全性的探索,為Res作為治療癲癇藥物的開(kāi)發(fā)提供更多有力依據(jù)。
[1]Giussani G,Cricelli C,Mazzoleni F,et al.Prevalence and Incidence of Epilepsy in Italy Based on a Nationwide Database[J].Neuroepidemiology,2014,43(3-4):228-232.
[2]Kaiboriboon K,Bakaki PM,Lhatoo SD,et al.Incidence and prevalence of treated epilepsy among poor health and lowincome Americans[J].Neurology,2013,80(21):1942-1949.
[3]林春蕾,郭傳勇.白藜蘆醇抗肝癌作用研究[J].中國(guó)醫(yī)藥導(dǎo)報(bào),2013,10(6):22-24.
[4]Pan QR,Ren YL,Liu WX,et al.Resveratrol prevents hepatic steatosis and endoplasmic reticulum stress and regulates the expression of genes involved in lipid metabolism,insulin resistance,and inflammation in rats[J].Nutrition Research,2015,35(7):576-584.
[5]Almeida L,Vaz-Da-Silva M,F(xiàn)alcao A,et al.Pharmacokinetic and safety profile of trans-resveratrol in a rising multiple-dose study in healthy volunteers[J].Molecular Nutrition&Food Research,2009,53(S1):S7-S15.
[6]Borriello A,Cucciolla V,Ragione FD,et al.Dietary polyphenols:Focus on resveratrol,a promising agent in the prevention of cardiovascular diseases and control of glucose homeostasis[J].Nutrition Metabolism&Cardiovascular Diseases Nmcd,2010,20(8):618-625.
[7]Baarine M,Thandapilly SJ,Louis XL,et al.Pro-apoptoticversus anti-apoptotic properties of dietary resveratrol on tumoral and normal cardiac cells[J].Genes&Nutrition,2011,6(2):161-169.
[8]Lu Z,Zhang Y,Liu H,et al.Transport of a cancer chemopreventivepolyphenol,resveratrol:Interaction with serum albumin and hemoglobin[J].J Fluoresc,2007,17(5):580-587.
[9]Boocock DJ,F(xiàn)aust GE,Patel KR,et al.Phase I doseescalation pharmacokinetic study in healthy volunteers of resveratrol,apotential cancer chemopreventiveagent[J].Cancer Epidemiol Biomarkers Prev,2007,16(6):1246-1252.
[10]Fang M,Xi ZQ,Wu Y,et al.A new hypothesis of drug refractory epilepsy:neural network hypothesis[J].Med Hypotheses,2011,76(6):871-876.
[11]WuY,F(xiàn)eng Y,Pang JR,et al.Study on expression of laminin in patients with intractable epilepsy[J].International Journal of Neuroscience,2009,119(12):2219-2227.
[12]Wu Z,Xu Q,Zhang L,et al.Protective Effect of Resveratrol against Kainate-induced Temporal Lobe Epilepsy in Rats[J].Neurochemical Research,2009,34(8):1393-400.
[13]尤竹燕,王斌生,解敏,等.白藜蘆醇對(duì)大鼠海馬CA1區(qū)誘發(fā)癲癇樣放電的影響[J].中國(guó)藥理學(xué)通報(bào),2012,28(2):260-265.
[14]Chiang YC,Hung TW,Lee WS,et al.Enhancement of tolerance development to morphine in rats prenatally exposed to morphine,methadone,and buprenorphine[J]. Journal of Biomedical Science,2010,17(1):284-290.
[15]李敏,潘群皖,王海華,等.白藜蘆醇對(duì)慢性癲癇大鼠腦組織中氨基酸類遞質(zhì)含量的影響[J].皖南醫(yī)學(xué)院學(xué)報(bào),2015(4):307-309.
[16]Tomé AR,F(xiàn)eng D,F(xiàn)reitas RM.The Effects of Alpha-Tocopherol on Hippocampal Oxidative Stress Prior to in Pilocarpine-Induced Seizures[J].Neurochemical Research,2010,35(4):580-587.
[17]Weise J,Engelhorn T,Dorfler A,et al.Expression time course and spatial distribution of activated caspase-3 after experimental status epilepticus:contribution of delayed neuronal cell death to seizure-induced neuronal injury[J].Neurobiology of Disease,2005,18(3):582-590.
[18]Gustafsson AB,Gottlieb RA.Bcl-2 family members and apoptosis,taken to heart[J].Am J Physiol Cell Physiol,2007,292(1):C45-C51.
[19]Wolter KG,Hsu YT,Smith CL,et al.Movement of Bax from the cytosol to mitochondria during apoptosis[J].J Cell Biol,1997,139(5):1281-1292.
[20]Clementi ME,Pezzotti M,Orsini F,et al.Alzheimer's amyloid beta-peptide(1-42)induces cell death in human neuroblastoma via bax/bcl-2 ratio increase:an intriguing role for methionine 35[J].BiochemBiophys Res Commun,2006,342(1):206-213.
[21]Sun ZK,Yang HQ,Wang ZQ,et al.Erythropoietin prevents PC12 cells from beta-amyloid-induced apoptosis via PI3K/Akt pathway[J].Transl Neurodegener,2012,1(1):7-10.
[22]郭家智,李燕玲,鐘蓮梅,等.白藜蘆醇調(diào)控癲癇持續(xù)狀態(tài)大鼠海馬內(nèi)源性巰醇抗氧化劑(酶)的作用[J].解剖學(xué)報(bào),2011,42(5):582-587.
[23]Pernhorst K,Herms S,Hoffmann P,et al.TLR4,ATF-3 and IL8 inflammation mediator expression correlates with seizure frequency in human epileptic brain tissue[J]. Seizure the Journal of the British Epilepsy Association,2013,22(8):675-678.
[24]Ashhab MU,Omran A,Kong H,et al.Expressions of tumor necrosis factor alpha and microRNA-155 in immature rat model of status epilepticus and children with mesial temporal lobe epilepsy[J].Journal of Molecular Neuroscience,2013,51(3):950-958.
[25]Nabbout R.Autoimmune and inflammatory epilepsies[J]. Epilepsia,2012,53(Suppl 4):58-62.
[26]Wang SJ,Bo QY,Zhao XH,et al.Resveratrol pretreatment reduces early inflammatory responses induced by status epilepticus via mTOR signaling[J].Brain Res,2012,1492:122-129
[27]Rao MS,Hattiangady B,Rai KS,et al.Strategies for promoting anti-seizure effects of hippocampal fetal cells grafted into the hippocampus of rats exhibiting chronic temporal lobe epilepsy[J].Neurobiol Dis,2007,27(2):111-132.
[28]Singleton RH,Yan HQ,F(xiàn)ellows-Mayle W,et al.Resveratrol attenuates behavioral impairments and reduces cortical and hippocampal loss in a rat controlled cortical impact model of traumatic brain injury[J].Journal of Neurotrauma,2010,27(6):1091-1099.
[29]Shin JA,Lee KE,Kim HS,et al.Acute resveratrol treatment modulates multiple signaling pathways in the ischemic brain[J].Neurochem Res,2012,37(12):2686-2696.
[30]Shetty AK.Promise of resveratrol for easing status epilepticus and epilepsy[J].Pharmacology&Therapeutics,2011,131(3):269-286.
[31]孟喜君,王峰,李傳坤.白藜蘆醇對(duì)戊四氮致癇大鼠的學(xué)習(xí)記憶能力的影響[J].中華神經(jīng)外科疾病研究雜志,2013,12(3):227-231.
Recent advances in the study on epilepsy treatment of resveratrol
LAN RuifangLI Zheng
Department of Neurology,the First People's Hospital of Qinzhou,the Guangxi Zhuang Autonomous Region,Qinzhou 535000,China
Epilepsy is a chronic,recurrent paroxysmal disease.About 20%-30%of epilepsy patients cannot be effectively controlled after rational therapy.Epilepsy pathogenesis complex and the antiepileptic drugs have certain shortcomings and some side effects.Resveratrol is a pleiotropic phytoalexin,which has a certain effect on epilepsy treatment.The antiepileptic mechanism of resveratrol includes inhibitting the abnormal discharge of epilepsy,reducing the inflammatory reaction after seizure,playing the antagonistic role on cell apoptosis induced by seizure and protective effects on neurons.
Epilepsy;Resveratrol;Abnormal discharge;Inflammatory reaction
R742.1
A
1673-7210(2016)07(b)-0038-03
2016-03-21本文編輯:趙魯楓)
廣西壯族自治區(qū)臨床重點(diǎn)??平ㄔO(shè)項(xiàng)目(桂衛(wèi)醫(yī)[2014]13號(hào));欽州市科學(xué)研究與技術(shù)開(kāi)發(fā)計(jì)劃項(xiàng)目(20145002)。