劉帥，胡磊，楊明,*

1.上海大學(xué)環(huán)境與化學(xué)工程學(xué)院，上海200444

2.上海大學(xué)生命科學(xué)學(xué)院，上海200444

G蛋白偶聯(lián)雌激素受體1介導(dǎo)的環(huán)境雌激素效應(yīng)研究進(jìn)展

劉帥1，胡磊2，楊明1,*

1.上海大學(xué)環(huán)境與化學(xué)工程學(xué)院，上海200444

2.上海大學(xué)生命科學(xué)學(xué)院，上海200444

環(huán)境雌激素進(jìn)入生物體后,可通過(guò)多種方式介導(dǎo)發(fā)揮類似內(nèi)源雌激素的作用,干擾生物體的正常功能,進(jìn)而對(duì)生物體產(chǎn)生毒害作用。其中,基因組方式介導(dǎo)的雌激素效應(yīng)主要通過(guò)與細(xì)胞核內(nèi)的雌激素受體(如ERα和ERβ)結(jié)合；而非基因組方式介導(dǎo)的雌激素效應(yīng)則主要通過(guò)與膜雌激素受體結(jié)合從而發(fā)揮作用。近年來(lái)對(duì)G蛋白偶聯(lián)雌激素受體1(GPER1)的研究表明,該受體是區(qū)別于雌激素核受體的膜雌激素受體,可單獨(dú)介導(dǎo)雌激素誘發(fā)的非基因組方式雌激素效應(yīng),然而目前對(duì)其介導(dǎo)的雌激素效應(yīng)機(jī)制研究并不完善。綜上,本文結(jié)合近年來(lái)對(duì)GPER1的研究進(jìn)展,從該受體的發(fā)現(xiàn)、特性以及其介導(dǎo)的雌激素效應(yīng)和相關(guān)通路進(jìn)行了綜述。

環(huán)境雌激素；膜雌激素受體；G蛋白偶聯(lián)雌激素受體

環(huán)境內(nèi)分泌干擾物(environmental endocrine disruptors,EEDs)是環(huán)境污染物的重要組成部分,可對(duì)生物體的內(nèi)分泌系統(tǒng)產(chǎn)生復(fù)合干擾損害作用,其中最重要的一類物質(zhì)環(huán)境雌激素(environmental estrogens)可誘導(dǎo)生物體產(chǎn)生雌激素效應(yīng),從而影響生物體的生殖系統(tǒng)[1]、神經(jīng)系統(tǒng)[2]、免疫系統(tǒng)[3]等的正常功能。

雌激素介導(dǎo)細(xì)胞的效應(yīng)機(jī)制主要分為2類:第一類是以傳統(tǒng)雌激素核受體ERα和ERβ介導(dǎo)為主的基因組效應(yīng),細(xì)胞核內(nèi)的雌激素受體不僅可直接結(jié)合目的DNA片段,還可以與其他核內(nèi)蛋白如雌激素的激活劑或抑制劑相互作用,從而增強(qiáng)或抑制基因的激活[4]；第二類是通過(guò)膜雌激素受體介導(dǎo)的快速非基因組效應(yīng),與傳統(tǒng)ER受體不同,膜性受體同細(xì)胞表面的內(nèi)源或外源雌激素產(chǎn)生結(jié)合或拮抗等作用,可在極短時(shí)間內(nèi)引發(fā)信號(hào)轉(zhuǎn)導(dǎo),如鉀離子通道關(guān)閉、鈣離子濃度升高以及相關(guān)通路的激活,從而影響有機(jī)體的正常功能,發(fā)揮其生物學(xué)效應(yīng)[5-6]。近年來(lái)關(guān)注并研究最多的膜雌激素受體是G蛋白偶聯(lián)雌激素受體1(G protein-coupled estrogen receptor 1, GPER1),文章對(duì)GPER1的研究進(jìn)展進(jìn)行了綜述。

1 GPER1的發(fā)現(xiàn)及組織分布(The discovery and tissue distribution of GPER1)

G蛋白偶聯(lián)雌激素受體1,最早稱之為G蛋白偶聯(lián)受體30(GPR30),是20世紀(jì)90年代從人體細(xì)胞中發(fā)現(xiàn)的一種膜雌激素受體,Carmeci等[7]從人體乳腺癌細(xì)胞系(MCF7)的cDNA文庫(kù)中篩選出一個(gè)全長(zhǎng)2 604 bp的cDNA序列,包括長(zhǎng)度為1 128 bp的開(kāi)放閱讀框(open read frame,ORF),可編碼成375個(gè)氨基酸的蛋白,分析發(fā)現(xiàn),該蛋白與早前報(bào)道的G蛋白偶聯(lián)受體(GPCRs)同源性很高,并命名為GPR30。該受體位于染色體7p22區(qū)域,具有7個(gè)跨膜疏水區(qū)域,但與大多數(shù)G蛋白偶聯(lián)受體不同, GPER1蛋白序列在第三跨膜區(qū)后存在一個(gè)保守的Asp-Arg-Tyr三聯(lián)體(DRY)序列,分析認(rèn)為可能與其介導(dǎo)的信號(hào)轉(zhuǎn)導(dǎo)有關(guān)[8]。其他研究團(tuán)隊(duì)同時(shí)期也發(fā)現(xiàn)并分離擴(kuò)增得到該受體基因,其序列信息基本相似[9-11]。

研究者相繼在哺乳類動(dòng)物如人(Homo sapiens)[9-11]和小家鼠(Mus musculus)[12-13]等,鳥(niǎo)類如雞(Gallus gallus)[14],兩棲類如蟾蜍(Xenopus)[15]和黑斑蛙(Rana nigromaculataH.)[16]等,硬骨魚(yú)類如細(xì)須石首魚(yú)(Micropogonias undulatus)[17]、斑馬魚(yú)(Danio rerio)[18]、斜帶石斑魚(yú)(Epinephelus coioides)[19]、金頭鯛(Sparus aurataL.)[20]等物種中均發(fā)現(xiàn)GPER1的存在。此外,GPER1在不同物種中的組織分布情況不同,雖然其在人體中的各組織中均有分布,包括心臟、腦、胎盤、肺、肝臟、肌肉、前列腺等,但在肺、肝臟和前列腺中表達(dá)較多,腦和性腺(卵巢、睪丸)中表達(dá)較少[21],然而在魚(yú)類中[18],GPER1的分布情況相反,在腦中表達(dá)最高,性腺次之,推測(cè)其原因可能是該受體在不同物種中的作用不同。

2 GPER1蛋白序列比對(duì)及進(jìn)化樹(shù)分析(The multiple alignment of protein sequences and phylogenetic tree analysis of GPER1)

圖1為基因庫(kù)中常見(jiàn)物種如人(human,Homo sapiens)、牛(cattle,Bos taurus)、小鼠(mouse,Mus musculus)、馬(horse,Equus caballus)、狗(dog,Canis lupus familiaris)、雞(chicken,Gallus gallus)、蟾蜍(toad, Gallus gallus)、石首魚(yú)(croaker,Micropogonias undulatus)、青鳉(medaka,Oryzias latipes)和斑馬魚(yú)(zebrafish,Danio rerio)的GPER1蛋白序列的序列比對(duì)(A)及進(jìn)化樹(shù)構(gòu)建結(jié)果(B)。比對(duì)結(jié)果表明,GPER1在不同物種之間的跨膜區(qū)域同源性均很高,且在第三跨膜區(qū)后存在DRY三聯(lián)體保守序列；此外,進(jìn)化樹(shù)分析發(fā)現(xiàn),GPER1基因在脊椎動(dòng)物中有明顯的分化,包括哺乳動(dòng)物、鳥(niǎo)類、兩棲動(dòng)物及硬骨魚(yú)類等。

3 GPER1的特性(The characteristics of GPER1)

早期研究過(guò)程中發(fā)現(xiàn),GPER1與傳統(tǒng)ER核受體的相關(guān)配體如17β-雌二醇(E2)、tamoxifen及ICI 182,780具有選擇性結(jié)合能力[22-26],但未找到GPER1的特異性配體,直到2006年Bologa等[27]通過(guò)虛擬和分子生物篩選融合法,從包括10 000個(gè)GPCRs結(jié)合配體的分子文庫(kù)中篩選出一個(gè)GPER1的特異性配體G1,驗(yàn)證后發(fā)現(xiàn),G1和雌激素一樣,可有效激活SkBr3細(xì)胞(不表達(dá)ERα、ERβ,但表達(dá)GPER1)和MCF7細(xì)胞(3種受體均有表達(dá))內(nèi)磷脂酰肌醇激酶PI3K的表達(dá),從而誘導(dǎo)磷脂酰肌醇三磷酸PIP3的產(chǎn)生。G1可特異性結(jié)合GPER1也可通過(guò)后續(xù)的研究得到證實(shí)[28-29]。

圖1 不同常見(jiàn)物種間的GPER1蛋白序列比對(duì)(A)及其進(jìn)化樹(shù)分析(B)注:各相關(guān)物種蛋白序列的基因庫(kù)登錄號(hào)分別為人,NP_001091671.1；牛,DAA15165.1；鼠,NP_084047.2；馬,XP_001488797；狗,XP_005621261.1；雞,NP_001155877.1；蟾蜍,NP_001107725.1；石首魚(yú),B0F9W3.1；青鳉,XP_004071380.1；斑馬魚(yú),NP_001122195.1。圖A中橫線所在位置代表7個(gè)跨膜區(qū)域(seven transmembrane domains,TM),方框位置代表DRY三聯(lián)體序列。Fig.1 Multiple alignment of protein sequences(A)and phylogenetic tree analysis(B)of GPER1 between different common speciesNote:The GenBank accession number of several protein sequences are as follows:human GPER1(NP_001091671.1),cattle GPR30 (DAA15165.1),mouse GPER1(NP_084047.2),horse GPER1(XP_001488797.1),dog GPER1(XP_005621261.1),chicken GPER1 (NP_001 515877.1),toad GPER1(NP_001107725.1),croaker GPR30(B0F9W3.1),medaka GPER1(XP_004071380.1),zebrafish GPER1(NP_001122195.1).The seven-transmembrane domains and DRY triplets were indicated by horizontal lines and open box in Fig.1A.

He等[30]將不表達(dá)ER的人體子宮內(nèi)膜癌KLE細(xì)胞系暴露于不同濃度的G1中,結(jié)果發(fā)現(xiàn),G1刺激后可有效促進(jìn)該細(xì)胞的增殖,并通過(guò)有絲分裂原活化蛋白激酶MAPK通路誘導(dǎo)基質(zhì)金屬蛋白酶的產(chǎn)生和白介素-6(IL-6)的分泌,表明GPER1可介導(dǎo)非基因組效應(yīng)在子宮內(nèi)膜癌研究中發(fā)揮重要作用；Sirianni等[31]發(fā)現(xiàn)在小鼠精原細(xì)胞系GC1中,G1、E2可通過(guò)GPER1和ERα的交互作用快速激活EGFR/ ERK/fos通路,進(jìn)而誘導(dǎo)小鼠精原細(xì)胞的增殖,但當(dāng)GPER1基因沉默后,增殖效應(yīng)消失。

此外,在2009年,Dennis等[32]從分子庫(kù)中篩選出一種化合物G15,并確認(rèn)其是GPER1的拮抗劑。與G1的化學(xué)結(jié)構(gòu)相比,G15化合物少一個(gè)乙?；?由于結(jié)構(gòu)的相似性而得到關(guān)注,通過(guò)配體結(jié)合實(shí)驗(yàn)表明,同G1類似,G15表現(xiàn)出較高的GPER1親和性,而與ERα、ERβ親和性很低,此外,G1、G15分別暴露和共暴露刺激小鼠子宮上皮細(xì)胞后,其增殖程度不同,G1組細(xì)胞顯著增殖,G15組幾乎無(wú)增殖,而共同刺激組較G1組增殖效果顯著降低,表明G15可作為GPER1的拮抗劑應(yīng)用于其在生物體內(nèi)作用機(jī)制的進(jìn)一步研究中。2011年,Dennis等[33]在G15的結(jié)構(gòu)基礎(chǔ)上增加一個(gè)異丙基,得到一種新的化合物G36,研究后發(fā)現(xiàn)也具有抑制GPER1表達(dá)的作用。

4 環(huán)境雌激素物質(zhì)對(duì)生物體的效應(yīng)機(jī)制研究(Mechanisms of actions of environmental estrogens on organisms)

雌激素的基因組效應(yīng)主要從3個(gè)方面進(jìn)行:(1)進(jìn)入細(xì)胞核內(nèi)的雌激素可激活核受體ERα或ERβ,與銜接蛋白和信號(hào)轉(zhuǎn)導(dǎo)分子作用,進(jìn)而影響下游通路；(2)激活目的基因啟動(dòng)子區(qū)域的ER二聚體從而調(diào)節(jié)細(xì)胞的基因表達(dá)變化；(3)促進(jìn)相關(guān)轉(zhuǎn)錄因子的磷酸化作用[34]。而進(jìn)一步的研究發(fā)現(xiàn),有的雌激素引起的下游效應(yīng)非?？焖?表明此效應(yīng)可能不需要經(jīng)過(guò)細(xì)胞核內(nèi)的雌激素受體,而在胞膜或質(zhì)膜發(fā)揮作用,與膜上的受體結(jié)合,激活相關(guān)通路等,從而誘導(dǎo)下游信號(hào)轉(zhuǎn)導(dǎo),該效應(yīng)被稱為非基因組效應(yīng)。

4.1 基因組效應(yīng)

環(huán)境雌激素的基因組效應(yīng)主要指由雌激素核受體(ER)作為雌激素類物質(zhì)的配體與進(jìn)入生物體內(nèi)的雌激素(天然或環(huán)境雌激素)結(jié)合,而介導(dǎo)的胞內(nèi)轉(zhuǎn)錄因子激活所引起的細(xì)胞內(nèi)反應(yīng)[5]。17α-乙炔基雌二醇(EE2)是一種合成激素,作為天然激素E2的衍生物而得到使用并大量進(jìn)入環(huán)境中,對(duì)生物體可能造成危害。在早期活體研究中發(fā)現(xiàn),在EE2長(zhǎng)期暴露下,可降低性成熟時(shí)期虹鱒魚(yú)的生育能力[35],破壞斑馬魚(yú)胚胎的性腺成熟[36]或降低成年斑馬魚(yú)的生殖腺指數(shù)[37],影響其正常生殖功能；離體實(shí)驗(yàn)也表明,較高濃度EE2暴露(100 nmol·L-1)可顯著降低雄性青鳉生殖細(xì)胞的增殖[38]。最初觀點(diǎn)認(rèn)為,環(huán)境雌激素效應(yīng)主要由ER介導(dǎo)。Cabas等[39]發(fā)現(xiàn),EE2刺激可顯著上調(diào)金頭鯛器官和細(xì)胞內(nèi)ERα的mRNA表達(dá),從而調(diào)節(jié)其免疫功能和性激素水平。同樣地, Yang等[40]以鯉魚(yú)巨噬細(xì)胞作為研究對(duì)象發(fā)現(xiàn),雙酚A也可通過(guò)誘導(dǎo)ERα的表達(dá)對(duì)魚(yú)體產(chǎn)生免疫毒性。此外,其他對(duì)雙酚A的研究中也得到類似研究結(jié)果[41-42]。綜上表明,ER作為轉(zhuǎn)錄因子,在雌激素誘導(dǎo)下所引起基因表達(dá)的變化足以影響細(xì)胞反應(yīng),進(jìn)而影響生物體。

4.2 非基因組效應(yīng)

在環(huán)境雌激素暴露下,傳統(tǒng)核受體可介導(dǎo)基因組效應(yīng),從而參與下游的信號(hào)轉(zhuǎn)導(dǎo),類似地,膜雌激素受體GPER1也具有調(diào)節(jié)雌激素相關(guān)基因表達(dá)的功能,即非基因組效應(yīng)機(jī)制。Rettew等[43]發(fā)現(xiàn),E2和G1刺激小鼠巨噬細(xì)胞后,在10～60 min內(nèi)TLR4的表達(dá)量顯著性降低,而在敲除GPER1后,TLR4的表達(dá)量趨于正常。在不表達(dá)ERα和ERβ的人體乳腺癌 SkBr3細(xì)胞系中,Vivacqua等[44]發(fā)現(xiàn),E2、tamoxifen和G1分別刺激1 h后,顯著上調(diào)細(xì)胞中早期生長(zhǎng)反應(yīng)因子(early growth response protein 1, EGR-1)的表達(dá),從而誘導(dǎo)結(jié)締組織生長(zhǎng)因子(connective tissue growth factor,CTGF)和細(xì)胞周期素D1的基因和蛋白表達(dá),促進(jìn)細(xì)胞增殖,而在RNA干擾沉默GPER1表達(dá)后,在同樣處理?xiàng)l件下相關(guān)基因的表達(dá)不再上調(diào)。最新研究發(fā)現(xiàn),tamoxifen和 ICI 182,780(ER拮抗劑)可在30 min內(nèi)激活GPER1促進(jìn)小鼠性興奮[45]。上述結(jié)果表明,與 ER相比, GPER1的表達(dá)可快速介導(dǎo)雌激素的下游信號(hào)轉(zhuǎn)導(dǎo),符合非基因組效應(yīng)的特點(diǎn)。

其他研究也表明,在不同濃度的環(huán)境雌激素類物質(zhì)暴露下,可通過(guò)激活GPER1調(diào)節(jié)不同種類細(xì)胞中相關(guān)基因的表達(dá)量。Catalano等[46]的研究發(fā)現(xiàn),對(duì)乳腺癌細(xì)胞長(zhǎng)期tamoxifen暴露攻毒后,可上調(diào)芳香化酶的mRNA表達(dá),促進(jìn)細(xì)胞增殖,而GPER1敲除及與拮抗劑共暴露后,上調(diào)現(xiàn)象消失；Pupo等[47]研究雙酚A對(duì)SkBr3細(xì)胞和癌癥相關(guān)纖維細(xì)胞CAFs(均不表達(dá) ER)的影響中發(fā)現(xiàn),可顯著上調(diào)GPER1目的基因c-fos、早期生長(zhǎng)反應(yīng)蛋白1和CTGF在細(xì)胞中的表達(dá),在GPER1基因沉默后,相關(guān)基因不再上調(diào)；Teng等[48]的研究發(fā)現(xiàn),GPER1過(guò)表達(dá)可消除因E2刺激而誘導(dǎo)的c-fos、c-jun及細(xì)胞周期蛋白D1的上調(diào)表達(dá),而RNA干擾導(dǎo)致GPER1失活后,反而上調(diào)這些基因的表達(dá)。進(jìn)一步地,環(huán)境雌激素可通過(guò)調(diào)節(jié)細(xì)胞內(nèi)相關(guān)基因的表達(dá),從而改變細(xì)胞的生長(zhǎng)情況。Bouskine等[49]和Liu等[50]的研究分別證實(shí)了GPER1在雙酚A促進(jìn)人體精原瘤細(xì)胞JKT-1增殖和E2促進(jìn)不表達(dá)ERα的卵巢癌細(xì)胞增殖過(guò)程中起關(guān)鍵作用。而Chimento等[51-52]則發(fā)現(xiàn)環(huán)境雌激素選擇性激活GPER1,可引起小鼠精母細(xì)胞和睪丸間質(zhì)腫瘤細(xì)胞的凋亡。由此可見(jiàn),雌激素膜受體如GPER1介導(dǎo)的環(huán)境雌激素非基因組效應(yīng)可快速但持久地激活細(xì)胞內(nèi)不同的雌激素信號(hào)通路,從而影響細(xì)胞的增殖情況及其功能。

5 GPER1相關(guān)信號(hào)轉(zhuǎn)導(dǎo)通路 (GPER1-related signal transduction pathways)

生物體中的GPER1受到雌激素刺激后,可快速介導(dǎo)非基因組效應(yīng),引起下游相關(guān)效應(yīng)變化,如參與部分基因的轉(zhuǎn)錄調(diào)控,調(diào)節(jié)基因表達(dá)量,引起細(xì)胞增殖或凋亡等,而GPER1激活后,主要通過(guò)介導(dǎo)相關(guān)信號(hào)轉(zhuǎn)導(dǎo)通路來(lái)引起上述效應(yīng)。通過(guò)對(duì)多年的研究總結(jié),其相關(guān)通路主要有以下4種:

5.1 EGFR-MAPKs通路

早期研究結(jié)果表明,雌激素在激活絲裂原活化蛋白激酶(mitogen-activated protein kinases,MAPKs)的過(guò)程中需要GPER1的參與[53]。Zhang等[54]發(fā)現(xiàn),雌激素可通過(guò)表皮生長(zhǎng)因子受體(epidermal growth factor receptor,EGFR)信號(hào)來(lái)誘導(dǎo)細(xì)胞外信號(hào)調(diào)節(jié)激酶-1/-2(extracellular signal-regulated kinase-1/-2, Erk-1/-2)即MAPKs的激活,進(jìn)而上調(diào)基質(zhì)金屬硫蛋白(matrix metalloproteinases,MMPs)的表達(dá),促進(jìn)細(xì)胞的遷移和侵襲能力,進(jìn)一步研究表明,在抑制GPER1和EGFR表達(dá)后,A549肺癌細(xì)胞的遷移和侵襲作用受到抑制。相似地,在G1功能研究過(guò)程中發(fā)現(xiàn),雌激素類化合物可通過(guò)GPER1反式激活EGFR,從而增強(qiáng)MAPK的磷酸化作用,在維持斑馬魚(yú)卵母細(xì)胞的減數(shù)分裂阻滯過(guò)程中起重要作用[55]。其他研究也證實(shí)GPER1參與MAPKs的激活過(guò)程[56-58]。

5.2 cAMP-PKA通路

作為細(xì)胞的“第二信使”,環(huán)磷酸腺苷(cyclic adenosine monophosphate,cAMP)是分子信號(hào)被刺激后,激活腺苷酸環(huán)化酶而催化ATP環(huán)化形成的。在精原瘤細(xì)胞JKT-1增殖實(shí)驗(yàn)中發(fā)現(xiàn),雙酚A與細(xì)胞接觸15 min后,可快速激活蛋白激酶A(protein kinase A,PKA)信號(hào)通路,隨即誘導(dǎo)cAMP反應(yīng)元件結(jié)合蛋白(cAMP response-element-binding protein, CREB)和細(xì)胞周期調(diào)節(jié)蛋白的快速磷酸化作用,進(jìn)而促進(jìn)JKT-1細(xì)胞的增殖[59]。進(jìn)一步的研究發(fā)現(xiàn),該快速雌激素效應(yīng)是由GPER1介導(dǎo)的非基因組效應(yīng)。此外,Yu等[60-61]的研究發(fā)現(xiàn),G1刺激可快速誘導(dǎo)cAMP的產(chǎn)生及增強(qiáng)PKA活性,進(jìn)而通過(guò)GPER/ cAMP/PKA信號(hào)通路促進(jìn)冠狀動(dòng)脈的舒張。此通路有時(shí)也與 MAPKs通路同時(shí)交互作用,通過(guò)GPER/PKA/ERK/CREB信號(hào)通路調(diào)節(jié)細(xì)胞的非正常效應(yīng)[62]。

5.3 PI3K-Akt通路

E2和G1刺激胰腺β細(xì)胞后,除可激活EGFR和Erk,還可通過(guò)促進(jìn)Akt即蛋白激酶B(protein kinase B,PKB)的磷酸化、提高磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinase,PI3K)的活性,增強(qiáng)胰島素的分泌能力[63]。Ruiz-Palmero等[64]研究GPER在小鼠海馬神經(jīng)元發(fā)育過(guò)程中的作用時(shí)發(fā)現(xiàn), GPER1可介導(dǎo)E2、G1等雌激素類化合物促進(jìn)Akt第473位的絲氨酸(ser473)磷酸化,而G15及PI3K抑制劑與雌激素共暴露刺激后,Akt激活效應(yīng)消失,雌激素效應(yīng)包括Ngn3基因的表達(dá)、神經(jīng)突觸形成等消失,表明GPER1可介導(dǎo)PI3K/Akt信號(hào)通路影響雌激素的生物效應(yīng)。后續(xù)研究也證實(shí)了GPER1介導(dǎo)PI3K信號(hào)的激活[65]。

5.4 Ca2＋通道

鈣離子通道(calcium channel)是跨越細(xì)胞膜上的控制鈣離子流動(dòng)的結(jié)構(gòu),該通道可調(diào)節(jié)細(xì)胞促炎效應(yīng)[66],而胞內(nèi)鈣離子濃度升高或下降可誘導(dǎo)神經(jīng)細(xì)胞功能障礙或死亡[67]。研究發(fā)現(xiàn),在小鼠心肌細(xì)胞中核受體ERα和ERβ基因的缺失與雌激素引起的抑制鈣離子內(nèi)流現(xiàn)象無(wú)關(guān)[68],然而G1刺激卻可顯著提高下丘腦神經(jīng)元[69]和COS7細(xì)胞[27]中的胞內(nèi)Ca2+濃度。此外,不同細(xì)胞暴露于E2后,都可通過(guò)激活GPER1而出現(xiàn)胞內(nèi)鈣動(dòng)員現(xiàn)象[70]。表明G1或雌激素可通過(guò)激活GPER1而引起細(xì)胞內(nèi)Ca2+濃度上升,從而異常調(diào)節(jié)細(xì)胞或機(jī)體的生理反應(yīng)。

6 結(jié)語(yǔ)(Conclusion)

G蛋白偶聯(lián)雌激素受體1作為一類雌激素受體,對(duì)其研究可追溯至20世紀(jì)90年代,而隨著時(shí)間的推移,GPER1的作用機(jī)制及功能研究也在不斷深入和完善,它不僅可與ER核受體交互作用,也可單獨(dú)介導(dǎo)雌激素誘發(fā)的信號(hào)轉(zhuǎn)導(dǎo),引發(fā)雌激素非基因組效應(yīng),進(jìn)而參與相關(guān)基因的轉(zhuǎn)錄調(diào)控,影響生物體的正常功能。然而,目前對(duì)于GPER1介導(dǎo)的環(huán)境雌激素效應(yīng)機(jī)制的研究主要集中在該受體高表達(dá)的各類癌化細(xì)胞中,而對(duì)其在正常生物體內(nèi)特別是接觸環(huán)境雌激素較多的水生生物中的作用機(jī)理研究還需進(jìn)一步深入。

[1]Jarmolowicz S,Demska-Zakes K,Zakes Z.Impact of din-butyl phthalate on reproductive system development in European pikeperch(Sander lucioperca)[J].Acta Veterinaria Brno,2013,82(2):197-201

[2]Guennoun R,Labombarda F,Gonzalez Deniselle M C,et al.Progesterone and allopregnanolone in the central nervous system:Response to injury and implication for neuroprotection[J].Journal of Steroid Biochemistry&Molecular Biology,2015,146:48-61

[3]Xu H,Yang M,Qiu W,et al.The impact of endocrinedisrupting chemicals on oxidative stress and innate immune response in zebrafish embryos[J].Environmental Toxicology and Chemistry,2013,32(8):1793-1799

[4]Moriarty K,Kim K H,Bender J R.Estrogen receptor-mediated rapid signaling[J].Endocrinology,2006,147(12): 5557-5563

[5]Meyer M R,Haas E,Prossnitz E R,et al.Non-genomic regulation of vascular cell function and growth by estrogen[J].Molecularand Cellular Endocrinology,2009,308 (1-2):9-16

[6]Han G C,Li F,Yu X,et al.GPER:A novel target for non-genomic estrogen action in the cardiovascular system [J].Pharmacological Research,2013,71:53-60

[7]Carmeci C,Thompson D A,Ring H Z,et al.Identification of a gene(GPR30)with homology to the G-protein-coupled receptor superfamily associated with estrogen receptor expression in breast cancer[J].Genomics,1997,45(3): 607-617

[8]Strader C D,Fong T M,Tota M R,et al.Structure and function of G protein-coupled receptors[J].Annual Review of Biochemistry,1994,63:101-132

[9]Feng Y,Gregor P.Cloning of a novel member of the G protein-coupled receptor family related to peptide receptors[J].Biochemical and Biophysical Research Communications,1997,231(3):651-654

[10]Kvingedal A M,Smeland E B.A novel putative G-protein-coupled receptor expressed in lung,heart and lymphoid tissue[J].FEBS Letters,1997,407(1):59-62

[11]O'Dowd B F,Nguyen T,Marchese A,et al.Discovery of three novel G-protein-coupled receptor genes[J].Genomics,1998,47(2):310-313

[12]Meoli L,Isensee J,Zazzu V,et al.Sex-and age-dependent effects of Gpr30 genetic deletion on the metabolic and cardiovascular profiles of diet-induced obese mice[J]. Gene,2014,540(2):210-216

[13]Lucas T F G,Royer C,Siu E R,et al.Expression and signaling of G protein-coupled estrogen receptor 1(GPER) in rat sertoli cells[J].Biology of Reproduction,2010,83 (2):307-317

[14]Ge C T,Yu M L,Zhang C Q.G protein-coupled receptor 30 mediates estrogen-induced proliferation of primordial germ cells via EGFR/Akt/beta-catenin signaling pathway [J].Endocrinology,2012,153(7):3504-3516

[15]Klein S L,Strausberg R L,Wagner L,et al.Genetic and genomic tools forXenopusresearch:The NIHXenopus initiative[J].Developmental Dynamics,2002,225(4): 384-391

[16]Shen X X,Liang D,Wen J Z,et al.Multiplegenome alignments facilitate development of NPCL markers:A case study of tetrapod phylogeny focusing on the position of turtles[J].Molecular Biology and Evolution,2011,28 (12):3237-3252

[17]Pang Y,Dong J,Thomas P.Estrogen signaling characteristics of Atlantic croaker G protein-coupled receptor 30 (GPR30)and evidence it is involved in maintenance of oocyte meiotic arrest[J].Endocrinology,2008,149(7): 3410-3426

[18]Liu X C,Zhu P,Sham K W Y,et al.Identification of amembrane estrogen receptor in zebrafish with homology to mammalian GPER and its high expression in early germ cells of the testis[J].Biology of Reproduction, 2009,80(6):1253-1261

[19]Nagarajan G,Tsai Y J,Chen C Y,et al.Developmental expression of genes involved in neural estrogen biosynthesis and signaling in the brain of the orange-spotted grouperEpinephelus coioidesduring gonadal sex differentiation[J].Journal of Steroid Biochemistry and MolecularBiology,2011,127(3-5):155-166

[20]Cabas I,Rodenas M C,Abellan E,et al.Estrogensignaling through the G protein-coupled estrogen receptor regulates granulocyte activation in fish[J].Journal of Immunology, 2013,191(9):4628-4639

[21]Owman C,Blay P,Nilsson C,et al.Cloning of human cDNA encoding a novel heptahelix receptor expressed in Burkitt's lymphoma and widely distributed in brain and peripheral tissues[J].Biochemical and Biophysical Research Communications,1996,228(2):285-292

[22]Kanda N,Watanabe S.17 beta-estradiol stimulates the growth of human keratinocytes by inducing cyclin D2 expression[J].Journal of Investigative Dermatology,2004, 123(2):319-328

[23]Maggiolini M,Vivacqua A,Fasanella G,et al.The G protein-coupled receptor GPR30 mediates c-fos up-regulation by 17 beta-estradiol and phytoestrogens in breast cancer cells[J].Journal of Biological Chemistry,2004,279(26): 27008-27016

[24]Thomas P,Pang Y,Filardo E J,et al.Identity of an estrogen membrane receptor coupled to a G protein in human breast cancer cells[J].Endocrinology,2005,146(2):624-632

[25]Filardo E J,Quinn J A,Frackelton A R,et al.Estrogen action via the G protein-coupled receptor,GPR30:Stimulation of adenylyl cyclase and cAMP-mediated attenuation of the epidermal growth factor receptor-to-MAPK signaling axis[J].Molecular Endocrinology,2002,16(1):70-84

[26]Chen Y,Li Z,He Y,et al.Estrogen and pure antiestrogen fulvestrant(ICI 182 780)augment cell-matrigel adhesion of MCF-7 breast cancer cells through a novel G protein coupled estrogen receptor(GPR30)-to-calpain signaling axis[J].Toxicology and Applied Pharmacology,2014, 275(2):176-181

[27]Bologa C G,Revankar C M,Young S M,et al.Virtual and biomolecular screening converge on a selective agonist for GPR30[J].Nature Chemical Biology,2006,2(4): 207-212

[28]Henic E,Noskova V,Hoyer-Hansen G,et al.Estradiolattenuates EGF-induced rapid uPAR mobilization and cell migration via the G-protein-coupled receptor 30 in ovarian cancer cells[J].International Journal of Gynecological Cancer,2009,19(2):214-222

[29]Otto C,Rohde-Schulz B,Schwarz G,et al.G protein-coupled receptor 30 localizes to the endoplasmic reticulum and is not activated by estradiol[J].Endocrinology,2008, 149(10):4846-4856

[30]He Y Y,Cai B,Yang Y X,et al.Estrogenic G proteincoupled receptor 30 signaling is involved in regulation of endometrial carcinoma by promoting proliferation,invasion potential,and interleukin-6 secretion via the MEK/ ERK mitogen-activated protein kinase pathway[J].Cancer Science,2009,100(6):1051-1061

[31]Sirianni R,Chimento A,Ruggiero C,et al.The novel estrogen receptor,G protein-coupled receptor 30,mediates the proliferative effects induced by 17 beta-estradiol on mouse spermatogonial GC-1 cell line[J].Endocrinology, 2008,149(10):5043-5051

[32]Dennis M K,Burai R,Ramesh C,et al.In vivoeffects of a GPR30 antagonist[J].Nature Chemical Biology,2009,5 (6):421-427

[33]Dennis M K,Field A S,Burai R,et al.Identification of a GPER/GPR30 antagonist with improved estrogen receptor counterselectivity[J].The Journal of Steroid Biochemistry and Molecular Biology,2011,127(3-5):358-366

[34]Barton M.Position paper:The membrane estrogen receptor GPER-Clues and questions[J].Steroids,2012,77(10): 935-942

[35]Schultz I R,Skillman A,Nicolas J-M,et al.Short-term exposure to 17α-ethynylestradiol decreases the fertility of sexually maturing male rainbow trout(Oncorhynchus mykiss)[J].Environmental Toxicology and Chemistry, 2003,22(6):1272-1280

[36]Xu H,Yang J,Wang Y,et al.Exposure to 17α-ethynylestradiol impairs reproductive functions of both male and female zebrafish(Danio rerio)[J].Aquatic Toxicology,2008,88(1):1-8

[37]Van den Belt K,Wester P W,van der Ven L T M,et al. Effects of ethynylestradiol on the reproductive physiology in zebrafish(Danio rerio):Time dependency and reversibility[J].Environmental Toxicology and Chemistry,2002, 21(4):767-775

[38]Song M,Gutzeit H O.Effect of 17-α-ethynylestradiol on germ cell proliferation in organ and primary culture of medaka(Oryzias latipes)testis[J].Development,Growth &Differentiation,2003,45(4):327-337

[39]Cabas I,Liarte S,García-Alcázar A,et al.17α-Ethynylestradiol alters the immune response of the teleost gilthead seabream(Sparus aurataL.)bothin vivoandin vitro [J].Developmental&Comparative Immunology,2012,36 (3):547-556

[40]Yang M,Qiu W,Chen B,et al.Thein vitroimmune modulatory effect of bisphenol A on fish macrophages via estrogen receptor alpha and nuclear factor-kappaB signaling [J].Environmental Science&Technology,2015,49(3): 1888-1895

[41]Li Y,Luh C J,Burns K A,et al.Endocrine-disrupting chemicals(EDCs):In vitromechanism of estrogenic activation and differential effects on ER target genes[J].Environmental Health Perspectives,2013,121(4):459-466

[42]Lee H-S,Park E-J,Oh J-H,et al.Bisphenol A exerts estrogenic effects by modulating CDK1/2 and p38 MAP kinase activity[J].Bioscience,Biotechnology,and Biochemistry,2014,78(8):1371-1375

[43]Rettew J A,McCall S H,Marriott I.GPR30/GPER-1 mediates rapid decreases in TLR4 expression on murine macrophages[J].Molecular and Cellular Endocrinology, 2010,328(1-2):87-92

[44]Vivacqua A,Romeo E,De Marco P,et al.GPER mediates the Egr-1 expression induced by 17 beta-estradiol and 4-hydroxitamoxifen in breast and endometrial cancer cells [J].Breast Cancer Research and Treatment,2012,133(3): 1025-1035

[46] Catalano S,Giordano C,Panza S,et al.Tamoxifen through GPER upregulates aromatase expression:A novel mechanism sustaining tamoxifen-resistant breast cancer cell growth[J].Breast Cancer Research and Treatment, 2014,146(2):273-285

[47]Pupo M,Pisano A,Lappano R,et al.Bisphenol A induces gene expression changes and proliferative effects through GPER in breast cancer cells and cancer-associated fibroblasts[J].Environmental Health Perspectives,2012,120 (8):1177-1182

[48]Teng J,Wang Z Y,Prossnitz E R,et al.The G proteincoupled receptor GPR30 inhibits human urothelial cell proliferation[J].Endocrinology,2008,149(8):4024-4034

[49]Chevalier N,Bouskine A,Fenichel P.Bisphenol A promotes testicularseminoma cellproliferation through GPER/GPR30[J].International Journal of Cancer,2012, 130(1):241-242

[50]Liu H D,Yan Y,Wen H X,et al.A novel estrogen receptor GPER mediates proliferation induced by 17 beta-estradiol and selective GPER agonist G-1 in estrogen receptor alpha(ER alpha)-negative ovarian cancer cells[J].Cell Biology International,2014,38(5):631-638

[51]Chimento A,Casaburi I,Bartucci M,et al.Selective GPER activation decreases proliferation and activates apoptosis in tumor Leydig cells[J].Cell Death Disease, 2013,4:e747

[52]Chimento A,Sirianni R,Casaburi I,et al.17 beta-Estradiol activates GPER-and ESR1-dependent pathways inducing apoptosis in GC-2 cells,a mouse spermatocyte-derived cell line[J].Molecular and Cellular Endocrinology, 2012,355(1):49-59

[53]Filardo E J.Epidermal growth factor receptor(EGFR) transactivation by estrogen via the G-protein-coupled receptor,GPR30:A novel signaling pathway with potential significance for breast cancer[J].Journal of Steroid Biochemistry and Molecular Biology,2002,80(2):231-238

[54]Zhang K S,Chen H Q,Chen Y S,et al.Bisphenol A stimulates human lung cancer cell migration via upregulation of matrix metalloproteinases by GPER/EGFR/ERK1/ 2 signal pathway[J].Biomedicine&Pharmacotherapy, 2014,68(8):1037-1043

[55]Peyton C,Thomas P.Involvement of epidermal growth factor receptor signaling in estrogen inhibition of oocyte maturation mediated through the G protein-coupled estrogen receptor(Gper)in zebrafish(Danio rerio)[J].Biology of Reproduction,2011,85(1):42-50

[56]Lappano R,De Marco P,De Francesco E M,et al.Crosstalk between GPER and growth factor signaling[J].Journalof Steroid Biochemistry and Molecular Biology,2013, 137:50-56

[57]Li Y,Chen Y,Zhu Z X,et al.4-Hydroxytamoxifen-stimulated processing of cyclin E is mediated via G proteincoupled receptor 30(GPR30)and accompanied by enhanced migration in MCF-7 breast cancer cells[J].Toxicology,2013,309:61-65

[58]Petrie W K,Dennis M K,Hu C,et al.G protein-coupled estrogen receptor-selective ligands modulate endometrial tumor growth[J].Obstetrics and Gynecology International,2013,2013(2013):472720

[59]Bouskine A,Nebout M,Brucker-Davis F,et al.Lowdoses of bisphenol A promote human seminoma cell proliferation by activating PKA and PKG via a membrane G-protein-coupled estrogen receptor[J].Environmental Health Perspectives,2009,117(7):1053-1058

[60]Yu X,Li F,White R,et al.Activation of G protein-coupled estrogen receptor 1(GPER)induces coronary artery relaxation via cAMP/PKA pathway[J].The FASEB Journal,2012,26

[61]Yu X,Li F,Klussmann E,et al.G protein-coupled estrogen receptor 1 mediates relaxation of coronary arteries via cAMP/PKA-dependent activation of MLCP[J].American JournalofPhysiology-Endocrinology and Metabolism, 2014,307(4):E398-E407

[62]Zhang X,Li J H,Duan S X,et al.Gprotein-coupled estrogen receptor-protein kinase A-ERK-CREB signaling pathway is involved in the regulation of mouse gubernaculum testis cells by diethylstilbestrol[J].Archives of Environmental Contamination and Toxicology,2014,67(1): 97-103

[63]Sharma G,Prossnitz E R.Mechanisms of estradiol-induced insulin secretion by the G protein-coupled estrogen receptor GPR30/GPER in pancreatic beta-cells[J].Endocrinology,2011,152(8):3030-3039

[64]Ruiz-Palmero I,Hernando M,Garcia-Segura L M,et al. G protein-coupled estrogen receptor is required for the neuritogenic mechanism of 17 beta-estradiol in developing hippocampal neurons[J].Molecularand Cellular Endocrinology,2013,372(1-2):105-115

[65]Guan B Z,Yan R L,Huang J W,et al.Activation of G protein coupled estrogen receptor(GPER)promotes the migration of renal cell carcinoma via the PI3K/AKT/ MMP-9 signals[J].Cell Adhesion&Migration,2015

[66]Espinosa-Parrilla J F,Martinez-Moreno M,Gasull X,et al.The L-type voltage-gated calcium channel modulates microglial pro-inflammatory activity[J].Molecular and Cellular Neuroscience,2014,6:104-115

[67]Anekonda T S,Quinn J F,Harris C,et al.L-type voltagegated calcium channel blockade with isradipine as a therapeutic strategy for Alzheimer's disease[J].Neurobiology of Disease,2011,41(1):62-70

[68]Ullrich N D,Ria H,Edenbrow M,et al.Genomic deletion of estrogen receptors does not alter the effects of estrogens on Ca influx and contraction in murine cardiomyocytes.[J].Biophysical Journal,2007:284a-284a

[69]Brailoiu E,Dun S L,Brailoiu G C,et al.Distribution and characterization of estrogen receptor G protein-coupled receptor 30 in the rat central nervous system[J].Journal of Endocrinology,2007,193(2):311-321

[70]Revankar C M,Cimino D F,Sklar L A,et al.A transmembrane intracellular estrogen receptor mediates rapid cell signaling[J].Science,2005,307(5715):1625-1630

Research Progress of the Effects of Environmental Estrogens Mediated by G Protein-Coupled Estrogen Receptor 1

Liu Shuai1,Hu Lei2,Yang Ming1,*
1.School of Environmental and Chemical Engineering,Shanghai University,Shanghai 200444,China
2.School of Life Sciences,Shanghai University,Shanghai 200444,China

17 April 2015 accepted 28 July 2015

Exogenous environmental estrogens can mimic endogenous estrogens in several ways.After entering the bodies,they may interfere with the normal function of organisms and produce some toxic effects on organisms.The genomic effects of estrogens are mainly mediated by estrogen receptors(ERs)in cell nucleus,such as ERα and ERβ;while the non-genomic effects of estrogens are mediated by a mechanism independent of the classical genomic pathway of estrogen action,which generally involves membrane-associated estrogen receptors.Recently,researchers have discovered that G protein-coupled estrogen receptor 1(GPER1),a membrane estrogen receptor different from the nuclear ERs,alone can mediate the effects on cells or organisms induced by estrogens.However,regarding the mechanism of GPER1 mediated estrogenic effects it is still illusive.In this review,the research progress of GPER1 was discussed in details including the discovery,and properties,as well as its mediated estrogenic effectsand the related pathways.

environmental estrogen;membrane-associated estrogen receptors;G protein-coupled estrogen receptor

2015-04-17 錄用日期:2015-07-28

1673-5897(2016)1-052-9

X171.5

A

10.7524/AJE.1673-5897.20150417004

劉帥,胡磊,楊明.G蛋白偶聯(lián)雌激素受體1介導(dǎo)的環(huán)境雌激素效應(yīng)研究進(jìn)展[J].生態(tài)毒理學(xué)報(bào),2016,11(1):52-60

Liu S,Hu L,Yang M.Research progress of the effects of environmental estrogens mediated by G protein-coupled estrogen receptor 1[J].Asian Journal of Ecotoxicology,2016,11(1):52-60(in Chinese)

國(guó)家自然科學(xué)基金(No.31470554)；上海市教委創(chuàng)新項(xiàng)目(No.14YZ001)

劉帥(1993-),男,碩士研究生,研究方向?yàn)榄h(huán)境內(nèi)分泌干擾物的毒性機(jī)制,E-mail:lslovetracyx@shu.edu.cn

),E-mail:mingyang@shu.edu.cn

簡(jiǎn)介:楊明(1979-)，女，博士，副研究員，主要研究方向水生生態(tài)毒理學(xué)。