针灸治疗大鼠溃疡性结肠炎细胞因子基因表达的探讨*
作者:吴焕淦 周丽斌 黄 诚 潘英英 陈汉平 施 征 华雪桂
单位:上海市针灸经络研究所 200030
关键词:结肠炎,溃疡性/治疗;针灸疗法;细胞因子;基因表达;RNA,信使
针灸治疗大鼠溃疡性结肠炎细胞因子基因表达的探讨 Gene expression of cytokines in acupuncture and moxibustion treatment for ulcerative colitis in rats*
WU Huan-Gan, ZHOU Li-Bin, HUANG Cheng, PAN Ying-Ying, CHEN Han Ping, SHI Zheng and HUA Xue-Gui
Shanghai Institute of Acupuncture-Moxibustion and Meridians, Shanghai 200030, China
, 百拇医药
Subject headings colitis, ulcerative/therapy; acupuncture and moxibustion; cytokines; gene expression; RNA, messenger
Abstract
AIM To observe the effect of acupuncture and moxibustion on the expression of IL-1β and IL-6 mRNA in ulcerative colitis rats.
METHODS Human fresh surgical colonic mucosa was homogenized by adding appropriate amount of normal saline and centrifuged at 3000r/min. Protein content of the supernatant was measured and then mixed with Freund adjuvant, and injected into the plantae of the model group rats, then into the plantea, dorsa, inguen and abdominal cavities (no Freund adjuvant for the last injection) on the 10th, 17th, 24th and 31st day respectively. When a certain titer of serum anti-colonic antibody was reached, 20mL/L formalin and antigen fluid (no Frenud adjuvant) were administered by enema to set up ulcerative colitis rat model. The animals were randomly divided into four groups: model control group (MC=8), electropuncture group (EP=8), herb spartition moxibustion group (HPM=8) and normal control group (NC=8). HPM: Mosa cones made of refined mugwort floss were placed on the medicinal pads (medicinal pad dispensing: Radix Aconiti praeparata, cortex Cinnamomi, etc) for Qihai (RN 6) and Tianshu (ST 25, bilateral) and ignited. Two moxa cones were used for each acupuncture once a day and 14 times in all. EP: Tianshu (bilateral) and Qihai were stimulated by the intermittent pulse with 2Hz frequency, 4mA intensity for 20 minutes once a day and 14 times in all. After treatment, all rats were killed simultaneously. The spleen was separated and the distal colon was dissected. Total tissue RNA was isolated by the guanidinium thiocyanate phenol-chloroform extraction method. RT-PCR technique was used to observe the expression of IL-1β and IL-6 mRNA.
, 百拇医药
RESULTS IL-1β and IL-6 mRNA was not detected in the spleen and colonic mucosa of NC rats, while it was significantly expressed in that of MC rats. IL-1β and IL-6 mRNA was markedly lower in EP and HPM rats than that in MC rats. There was no significant difference in the levels of IL-1β and IL-6 mRNA between EP and HPW rats. The amount of IL-1β and IL-6 mRNA was nearly the same between the spleen and colon in different groups.
CONCLUSION Acupuncture and moxibustion greatly inhibited the expression of IL-1β and IL-6 mRNA in the ulcerative colitis rats.
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中国图书资料分类号 R574.62
摘 要
目的 观察针灸对溃疡性结肠炎大鼠IL-1β和IL-6mRNA表达的影响.
方法 采用人结肠术后新鲜结肠粘膜,加适量生理盐水制成粘膜匀浆,以3000r/min离心,取上清液,测定蛋白含量,并与Fruend佐剂混合配成乳剂. 模型组大鼠首次足跖内注射抗原后,并于d10,d17,d24,d31分别于足跖、 背部、腹股沟、腹腔内(末次注射不加佐剂)加强注射,至血清抗结肠抗体到一定效价后,再用20mL/L福尔马林和抗原液(不加佐剂)分别灌肠,建立溃疡性结肠炎大鼠模型. 随机分为模型对照组(8只),电针组(8只),隔药灸组(8只). 正常对照组大鼠8只. 隔药灸组:用精制艾绒制成的艾炷在天枢(双)、气海穴位上隔药饼(药饼配方:附子、肉桂等药)灸2壮,1次/d,共14次;电针组:用间歇式脉冲波刺激天枢(双),气海,频率2Hz,强度4mA,时间20min,1次/d,共14次. 治疗结束后,四组大鼠同时处死,分离脾脏、割取远端结肠. 采用异硫氰酸胍/酚/氯仿一步法抽提组织总RNA,逆转录-聚合酶链反应(RT-PCR)技术观察组织中IL-1β,IL-6 mRNA的表达.
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结果 正常对照组大鼠脾脏、结肠粘膜中未见IL-1β,IL-6 mRNA的表达,模型对照组中有大量表达,电针组、隔药灸组较模型对照组其IL-1β,IL-6 mRNA含量显著降低,电针组与隔药灸组之间无显著差异. 各组中脾脏、结肠粘膜间的表达量基本一致.
结论 针灸对溃疡性结肠炎大鼠中的IL-1β,IL-6 mRNA表达具有明显抑制作用.
0 引言
溃疡性结肠炎(ulcerative colitis, UC)是一种非特异性炎性肠病,其病因尚未完全清楚,但其发病与免疫功能紊乱有关已得到普遍认可[1]. 而具有免疫调节作用的细胞因子在UC的发病过程中起重要作用,尤其是由淋巴、单核-巨噬细胞分泌、具有炎性递质特性的IL-1β,IL-6等细胞因子通过不同途径参与肠粘膜炎症形成的起始阶段和发展过程,是介导UC发病的关键因素之一[2]. 针灸治疗UC具有良好的疗效,临床和实验研究表明,针灸治疗UC的作用机制与其调整异常的免疫功能有关[3,4],但对于细胞因子在其中所起的作用尚未见报道. 我们采用免疫学方法建立UC的大鼠模型,观察针灸对模型大鼠脾脏、结肠粘膜IL-1β,IL-6 mRNA表达的影响,以进一步阐明针灸治疗UC的可能作用机制.
, 百拇医药
1 材料和方法
1.1 材料 SD ♂大鼠32只,体重140g±20g,由上海中医药大学实验动物中心提供. 随机分为模型组(24)只,正常组(8)只. 造模方法:采用人术后新鲜结肠粘膜,加适量生理盐水制成粘膜匀浆,冷冻24h,溶冻后以3000r/min速度离心30min,取上清液提纯测定蛋白质含量,并与Freund佐剂混合配成乳剂. 模型组大鼠首次每只足跖内注射抗原3mg,并于d10,d17,d24,d31分别于足跖、背部、腹股沟、腹腔内注射抗原6mg(末次注射不加Freund佐剂),至血清抗结肠抗体达到一定效价,对模型大鼠用100mL/L水合氯醛ip麻醉,用20mL/L福尔马林(FS)2mL灌肠,留置1h,用生理盐水洗净后排去,再用抗原液(4g/L,不加佐剂)2mL灌肠,留置2h,洗净排去[5]. 正常组用生理盐水作与模型组相同处理. 造模结束后,将模型组大鼠随机分为模型对照组(8只)、电针组(8只)、隔药灸组(8只). 取穴:气海、天枢(双)、穴位定位根据人体定位法类比而定. 隔药灸组:艾炷以精制艾绒制成重约90mg/只,在气海,天枢穴位上隔药饼(药饼配方:附子、肉桂等药)灸2壮,1次/d,共14次;电针组:用6805型电针治疗仪输出间歇式脉冲波刺激天枢、气海,频率2Hz,强度4mA,时间20min,1次/d,共14次. 四组于治疗结束后同时断头处死,迅速分离脾脏,割取远端结肠6cm,置液氮保存备用.
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1.2 方法 ①按参考文献[6]采用异硫氰酸胍/酚/氯仿一步法抽提总RNA,紫外分光光度计OD260测RNA样品的浓度,10g/L琼脂糖凝胶电泳鉴定RNA的完整性. ②2μg总RNA逆转录合成cDNA,20μL逆转录反应体系(Promega)包括:10×逆转录缓冲液2μL,25mmol/L,MgCl2, 4μL,4×dNTPs(各10mmol/L),2μL,RNA酶抑制剂0.5μL (20U),AMV逆转录酶0.65μL (15U),寡聚(dT)15,引物1μL(0.5μg),加DEPC水至20μL混匀,42℃水浴40min,95℃加热5min以灭活逆转录酶,-20℃保存. ③引物根据参考文献设计[7],由中科院细胞所癌基因实验室合成,其序列为:IL-1β,ATAGCAGCTTTCGACAGTGAG(正义链),GTCAACTATGTCCCGACCATT(反义链)748bp;IL-6,TTCCCTACTTCACAAGTC(正义链),CTAGGTTTGCCGAGTAGA(反义链)567bp;GAPDH(三磷酸甘油醛脱氢酶)TGAAGGTCGGTGTCAACGGATTTGTC(正义链),CAGTAGGCCATGAGGTCCACCAC(反义链)983bp. GAPDH作为“看家基因”(house-keeping gene)以监控RNA使用量,消除不同样本间加样误差. ④PCR反应总体积50μL(华美)包括10×扩增缓冲液5μL,4×dNTPs(各2.5mmol/L)4μL,正、反义链引物各50pmoL,2μL逆转录产物,Taq DNA聚合酶2.5U,加ddH2O至50μL混匀,离心10s后加入50μL液体石蜡,置PCR热循环仪(Pharmacia)扩增. 扩增条件:IL-1β:94℃预变性4min,94℃ 30s,50℃ 45s,72℃ 90s,30个循环. IL-6,GAPDH:94℃预变性4min,94℃ 1min,52℃ 1min,72℃ 1min,30个循环. ⑤取10μL PCR产物,加入6×电泳加样缓冲液2μL于15g/L琼脂糖凝胶(含溴化乙锭0.5mg/L,100V电泳1h,紫外灯下观察照相.
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2 结果
总RNA抽提结果. 总RNA样品测定OD260/OD280比值介于1.70~2.00之间,电泳显示18s,28s两条清晰条带,无其它大分子条带,表明总RNA无污染、无降解.
脾脏、结肠粘膜IL-1β,IL-6 mRNA结果(图1). 本实验模型对照组、电针组、隔药灸组大鼠脾脏、结肠粘膜均有IL-1β,IL-6 mRNA表达,电针组、隔药灸组与模型对照组相比表达量明显减少. 电针组与隔药灸组无显著差异,但隔药灸组其表达量相对较少,各组的脾脏与结肠粘膜的表达量基本一致,正常组脾脏、结肠粘膜未见有IL-1β,IL-6 mRNA的表达.
3 讨论
UC的发病不仅涉及系统免疫功能紊乱,还存在着肠道粘膜局部免疫功能的异常,而细胞因子参与免疫反应和炎症过程,正成为当前研究UC发病机制的热点. IL-1β,IL-6作为重要的炎性因子和免疫调节剂,在UC的发病中颇受重视. 众多研究表明,UC患者的结肠粘膜、外周血中IL-1β,IL-6表达增高,尤其是IL-6可能与UC的病情、临床表现相关[8,9]. IL-1β,IL-6主要由活化的巨噬细胞、淋巴细胞分泌,具有多向生物学效应,能通过自分泌或旁分泌刺激其他细胞因子和炎症递质的产生,诱发抗原提呈细胞(APC)表面免疫分子的表达,为T淋巴细胞的活化提供第二信号,促进B细胞的增殖、分化、介导免疫球蛋白的分泌,由此激活补体,杀伤细胞及吞噬细胞的活性,增强细胞免疫和体液免疫介导组织损伤的过程. 此外,IL-1β,IL-6还能促进血管内皮-白细胞粘附分子的表达,趋化中性粒细胞等炎性细胞进入肠道病变部位,从而引起一系列肠道炎症反应和组织破坏[10-12].
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生理状态下大鼠脾脏、结肠粘膜内未检测出细胞因子,而造模大鼠脾脏、结肠粘膜内IL-1β,IL-6等炎性细胞因子水平显著提高,这可能是由于在外来抗原的持续刺激下,大鼠的淋巴、单核-巨噬细胞被激活,而促使细胞因子的表达,脾脏、结肠粘膜IL-1β,IL-6 mRNA表达量基本一致,提示两者的免疫细胞对抗原的反应可能是相似的,并通过细胞因子的内分泌途径起相互作用. 本实验中电针组、隔药灸组IL-1β,IL-6 mRNA表达显著下降,表明针灸可以抑制模型大鼠脾脏、结肠粘膜炎性细胞因子的基因表达,纠正异常的免疫功能,降低免疫细胞对炎症的反应性,从而有利于炎症的消除,组织的修复.
UC的发病过程不仅涉及到炎性细胞因子的作用,也有抗炎免疫因子(IL-4,IL-ra,IL-10等)的参与,是两者平衡失调的结果,针灸作用机制除抑制炎性细胞因子的表达外,是否激发抗炎免疫因子的参与,仍有待于进一步研究.
, 百拇医药
图1 针灸对溃疡性结肠炎大鼠脾脏、结肠粘膜IL-1β,IL-6 mRNA的影响.
M:PCR标志(华美)由上至下为1543,994,695,515,377,237bp.
1,3,5,7分别为模型对照组、电针组、隔药灸组、正常组的结肠粘膜mRNA;2,4,6,8分别为模型对照组、电针组、隔药灸组、正常组的脾脏mRNA.
吴焕淦,男,1956-11-21生,浙江省仙居县人,1990年浙江中医学院硕士,1993年上海中医药大学博士,副教授,副所长,主要从事针灸免疫学研究,发表论文20篇.
*国家自然科学基金资助项目,No.39670899.
通讯作者 吴焕淦,200030,上海市针灸经络研究所.
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*Supported by the National Natural Science Foundation of China, No.39670899.
Correspondence to:Vice-Prof. WU Huan-Gan, Shanghai Institute of Acupuncture-Moxibustion and Meridians, 650 Wanping Nanlu, Shanghai 200030, China
Tel. +86*21*64395972
收稿日期 1998-07-07
4 参考文献
1 Kusugami K, Fukatsu A, Tanimoto M, Shinoda M, Haruta J, Kuroiwa A et al. Elevation of interleukin-6 in inflammatory bowel disease is macrophage-and epithelial cell-dependent. Dig Dis Sci, 1995;40(5):949-957
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2 Xia B, Guo HJ, Crusius JBA, Deng CH, Meuwissen SGM, Pena AS. In vitro production of TNFα, IL6 and sIL2R in Chinese patients with ulcerative colitis. WJG, 1998;4(3):252-255
3 吴焕淦,陈汉平,华雪桂,施征,张琳珊,陈及灵. 隔药灸治疗慢性腹泻的临床疗效及免疫学机理探讨. 中医杂志,1995;36(1):25-27
4 吴焕淦,陈汉平,廖柏松,施征,张琳珊. 隔药灸对大鼠实验性结肠炎免疫功能及β-内啡肽的影响. 中国针灸,1997;17(3):163-165
5 吴焕淦,陈汉平,王楠,赵粹英,陈及灵,施征 et al. 溃疡性结肠炎动物模型与隔药灸治疗作用的形态学研究. 中国针灸,1994;14(3):35-37
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6 Chomczynski P, Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chlorlform extraction. Anal Biochem, 1987;162(1):156-159
7 Murphy PG, Grondin J, Altares M, Richardson PM. Induction of interleukin-6 in axotomized sensory neurons. J Neurosci, 1995;15(7):5130-5132
8 Mitsuyama K, Toyonaga A, Sasaki E, Ishida O, Ikeda H,Tsuruta O et al. Soluble interleukin-6 receptors in inflammatory bowel disease: relation to circulating interleukin-6. Gut, 1995;36(1):45-49
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9 Stevens C, Walz G, Singaram C, Lipman ML, Zanker B, Muggia A et al. Tumor necrosis factor-α, interleukin-1β, and interleukin-6, expression in inflammatory bowel disease. Dig Dis Sci, 1992;37(6):818-819
10 Hogaboam CM, Snider DP, Collins SM. Cytokine modulation of T-lymphocyte activation by intestinal smooth muscle cells. Gastroenterology, 1997;112(6):1986-1994
11 Nassif A, Longo We, Mazuski JE, Vernava AM, Kaminski DL. Role of cytokines and platelet-activating fator inflammatory bowel disease. Dis Colon Rectum, 1996;39(2):219-220
12 Schreiber S, Raedler A, Stenson WF, MacDermott RP. The role of mucosal immune system in inflammatory bowel disease. Gastroenterol Clin North Am, 1992;21(2):469-471, 百拇医药
单位:上海市针灸经络研究所 200030
关键词:结肠炎,溃疡性/治疗;针灸疗法;细胞因子;基因表达;RNA,信使
针灸治疗大鼠溃疡性结肠炎细胞因子基因表达的探讨 Gene expression of cytokines in acupuncture and moxibustion treatment for ulcerative colitis in rats*
WU Huan-Gan, ZHOU Li-Bin, HUANG Cheng, PAN Ying-Ying, CHEN Han Ping, SHI Zheng and HUA Xue-Gui
Shanghai Institute of Acupuncture-Moxibustion and Meridians, Shanghai 200030, China
, 百拇医药
Subject headings colitis, ulcerative/therapy; acupuncture and moxibustion; cytokines; gene expression; RNA, messenger
Abstract
AIM To observe the effect of acupuncture and moxibustion on the expression of IL-1β and IL-6 mRNA in ulcerative colitis rats.
METHODS Human fresh surgical colonic mucosa was homogenized by adding appropriate amount of normal saline and centrifuged at 3000r/min. Protein content of the supernatant was measured and then mixed with Freund adjuvant, and injected into the plantae of the model group rats, then into the plantea, dorsa, inguen and abdominal cavities (no Freund adjuvant for the last injection) on the 10th, 17th, 24th and 31st day respectively. When a certain titer of serum anti-colonic antibody was reached, 20mL/L formalin and antigen fluid (no Frenud adjuvant) were administered by enema to set up ulcerative colitis rat model. The animals were randomly divided into four groups: model control group (MC=8), electropuncture group (EP=8), herb spartition moxibustion group (HPM=8) and normal control group (NC=8). HPM: Mosa cones made of refined mugwort floss were placed on the medicinal pads (medicinal pad dispensing: Radix Aconiti praeparata, cortex Cinnamomi, etc) for Qihai (RN 6) and Tianshu (ST 25, bilateral) and ignited. Two moxa cones were used for each acupuncture once a day and 14 times in all. EP: Tianshu (bilateral) and Qihai were stimulated by the intermittent pulse with 2Hz frequency, 4mA intensity for 20 minutes once a day and 14 times in all. After treatment, all rats were killed simultaneously. The spleen was separated and the distal colon was dissected. Total tissue RNA was isolated by the guanidinium thiocyanate phenol-chloroform extraction method. RT-PCR technique was used to observe the expression of IL-1β and IL-6 mRNA.
, 百拇医药
RESULTS IL-1β and IL-6 mRNA was not detected in the spleen and colonic mucosa of NC rats, while it was significantly expressed in that of MC rats. IL-1β and IL-6 mRNA was markedly lower in EP and HPM rats than that in MC rats. There was no significant difference in the levels of IL-1β and IL-6 mRNA between EP and HPW rats. The amount of IL-1β and IL-6 mRNA was nearly the same between the spleen and colon in different groups.
CONCLUSION Acupuncture and moxibustion greatly inhibited the expression of IL-1β and IL-6 mRNA in the ulcerative colitis rats.
, http://www.100md.com
中国图书资料分类号 R574.62
摘 要
目的 观察针灸对溃疡性结肠炎大鼠IL-1β和IL-6mRNA表达的影响.
方法 采用人结肠术后新鲜结肠粘膜,加适量生理盐水制成粘膜匀浆,以3000r/min离心,取上清液,测定蛋白含量,并与Fruend佐剂混合配成乳剂. 模型组大鼠首次足跖内注射抗原后,并于d10,d17,d24,d31分别于足跖、 背部、腹股沟、腹腔内(末次注射不加佐剂)加强注射,至血清抗结肠抗体到一定效价后,再用20mL/L福尔马林和抗原液(不加佐剂)分别灌肠,建立溃疡性结肠炎大鼠模型. 随机分为模型对照组(8只),电针组(8只),隔药灸组(8只). 正常对照组大鼠8只. 隔药灸组:用精制艾绒制成的艾炷在天枢(双)、气海穴位上隔药饼(药饼配方:附子、肉桂等药)灸2壮,1次/d,共14次;电针组:用间歇式脉冲波刺激天枢(双),气海,频率2Hz,强度4mA,时间20min,1次/d,共14次. 治疗结束后,四组大鼠同时处死,分离脾脏、割取远端结肠. 采用异硫氰酸胍/酚/氯仿一步法抽提组织总RNA,逆转录-聚合酶链反应(RT-PCR)技术观察组织中IL-1β,IL-6 mRNA的表达.
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结果 正常对照组大鼠脾脏、结肠粘膜中未见IL-1β,IL-6 mRNA的表达,模型对照组中有大量表达,电针组、隔药灸组较模型对照组其IL-1β,IL-6 mRNA含量显著降低,电针组与隔药灸组之间无显著差异. 各组中脾脏、结肠粘膜间的表达量基本一致.
结论 针灸对溃疡性结肠炎大鼠中的IL-1β,IL-6 mRNA表达具有明显抑制作用.
0 引言
溃疡性结肠炎(ulcerative colitis, UC)是一种非特异性炎性肠病,其病因尚未完全清楚,但其发病与免疫功能紊乱有关已得到普遍认可[1]. 而具有免疫调节作用的细胞因子在UC的发病过程中起重要作用,尤其是由淋巴、单核-巨噬细胞分泌、具有炎性递质特性的IL-1β,IL-6等细胞因子通过不同途径参与肠粘膜炎症形成的起始阶段和发展过程,是介导UC发病的关键因素之一[2]. 针灸治疗UC具有良好的疗效,临床和实验研究表明,针灸治疗UC的作用机制与其调整异常的免疫功能有关[3,4],但对于细胞因子在其中所起的作用尚未见报道. 我们采用免疫学方法建立UC的大鼠模型,观察针灸对模型大鼠脾脏、结肠粘膜IL-1β,IL-6 mRNA表达的影响,以进一步阐明针灸治疗UC的可能作用机制.
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1 材料和方法
1.1 材料 SD ♂大鼠32只,体重140g±20g,由上海中医药大学实验动物中心提供. 随机分为模型组(24)只,正常组(8)只. 造模方法:采用人术后新鲜结肠粘膜,加适量生理盐水制成粘膜匀浆,冷冻24h,溶冻后以3000r/min速度离心30min,取上清液提纯测定蛋白质含量,并与Freund佐剂混合配成乳剂. 模型组大鼠首次每只足跖内注射抗原3mg,并于d10,d17,d24,d31分别于足跖、背部、腹股沟、腹腔内注射抗原6mg(末次注射不加Freund佐剂),至血清抗结肠抗体达到一定效价,对模型大鼠用100mL/L水合氯醛ip麻醉,用20mL/L福尔马林(FS)2mL灌肠,留置1h,用生理盐水洗净后排去,再用抗原液(4g/L,不加佐剂)2mL灌肠,留置2h,洗净排去[5]. 正常组用生理盐水作与模型组相同处理. 造模结束后,将模型组大鼠随机分为模型对照组(8只)、电针组(8只)、隔药灸组(8只). 取穴:气海、天枢(双)、穴位定位根据人体定位法类比而定. 隔药灸组:艾炷以精制艾绒制成重约90mg/只,在气海,天枢穴位上隔药饼(药饼配方:附子、肉桂等药)灸2壮,1次/d,共14次;电针组:用6805型电针治疗仪输出间歇式脉冲波刺激天枢、气海,频率2Hz,强度4mA,时间20min,1次/d,共14次. 四组于治疗结束后同时断头处死,迅速分离脾脏,割取远端结肠6cm,置液氮保存备用.
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1.2 方法 ①按参考文献[6]采用异硫氰酸胍/酚/氯仿一步法抽提总RNA,紫外分光光度计OD260测RNA样品的浓度,10g/L琼脂糖凝胶电泳鉴定RNA的完整性. ②2μg总RNA逆转录合成cDNA,20μL逆转录反应体系(Promega)包括:10×逆转录缓冲液2μL,25mmol/L,MgCl2, 4μL,4×dNTPs(各10mmol/L),2μL,RNA酶抑制剂0.5μL (20U),AMV逆转录酶0.65μL (15U),寡聚(dT)15,引物1μL(0.5μg),加DEPC水至20μL混匀,42℃水浴40min,95℃加热5min以灭活逆转录酶,-20℃保存. ③引物根据参考文献设计[7],由中科院细胞所癌基因实验室合成,其序列为:IL-1β,ATAGCAGCTTTCGACAGTGAG(正义链),GTCAACTATGTCCCGACCATT(反义链)748bp;IL-6,TTCCCTACTTCACAAGTC(正义链),CTAGGTTTGCCGAGTAGA(反义链)567bp;GAPDH(三磷酸甘油醛脱氢酶)TGAAGGTCGGTGTCAACGGATTTGTC(正义链),CAGTAGGCCATGAGGTCCACCAC(反义链)983bp. GAPDH作为“看家基因”(house-keeping gene)以监控RNA使用量,消除不同样本间加样误差. ④PCR反应总体积50μL(华美)包括10×扩增缓冲液5μL,4×dNTPs(各2.5mmol/L)4μL,正、反义链引物各50pmoL,2μL逆转录产物,Taq DNA聚合酶2.5U,加ddH2O至50μL混匀,离心10s后加入50μL液体石蜡,置PCR热循环仪(Pharmacia)扩增. 扩增条件:IL-1β:94℃预变性4min,94℃ 30s,50℃ 45s,72℃ 90s,30个循环. IL-6,GAPDH:94℃预变性4min,94℃ 1min,52℃ 1min,72℃ 1min,30个循环. ⑤取10μL PCR产物,加入6×电泳加样缓冲液2μL于15g/L琼脂糖凝胶(含溴化乙锭0.5mg/L,100V电泳1h,紫外灯下观察照相.
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2 结果
总RNA抽提结果. 总RNA样品测定OD260/OD280比值介于1.70~2.00之间,电泳显示18s,28s两条清晰条带,无其它大分子条带,表明总RNA无污染、无降解.
脾脏、结肠粘膜IL-1β,IL-6 mRNA结果(图1). 本实验模型对照组、电针组、隔药灸组大鼠脾脏、结肠粘膜均有IL-1β,IL-6 mRNA表达,电针组、隔药灸组与模型对照组相比表达量明显减少. 电针组与隔药灸组无显著差异,但隔药灸组其表达量相对较少,各组的脾脏与结肠粘膜的表达量基本一致,正常组脾脏、结肠粘膜未见有IL-1β,IL-6 mRNA的表达.
3 讨论
UC的发病不仅涉及系统免疫功能紊乱,还存在着肠道粘膜局部免疫功能的异常,而细胞因子参与免疫反应和炎症过程,正成为当前研究UC发病机制的热点. IL-1β,IL-6作为重要的炎性因子和免疫调节剂,在UC的发病中颇受重视. 众多研究表明,UC患者的结肠粘膜、外周血中IL-1β,IL-6表达增高,尤其是IL-6可能与UC的病情、临床表现相关[8,9]. IL-1β,IL-6主要由活化的巨噬细胞、淋巴细胞分泌,具有多向生物学效应,能通过自分泌或旁分泌刺激其他细胞因子和炎症递质的产生,诱发抗原提呈细胞(APC)表面免疫分子的表达,为T淋巴细胞的活化提供第二信号,促进B细胞的增殖、分化、介导免疫球蛋白的分泌,由此激活补体,杀伤细胞及吞噬细胞的活性,增强细胞免疫和体液免疫介导组织损伤的过程. 此外,IL-1β,IL-6还能促进血管内皮-白细胞粘附分子的表达,趋化中性粒细胞等炎性细胞进入肠道病变部位,从而引起一系列肠道炎症反应和组织破坏[10-12].
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生理状态下大鼠脾脏、结肠粘膜内未检测出细胞因子,而造模大鼠脾脏、结肠粘膜内IL-1β,IL-6等炎性细胞因子水平显著提高,这可能是由于在外来抗原的持续刺激下,大鼠的淋巴、单核-巨噬细胞被激活,而促使细胞因子的表达,脾脏、结肠粘膜IL-1β,IL-6 mRNA表达量基本一致,提示两者的免疫细胞对抗原的反应可能是相似的,并通过细胞因子的内分泌途径起相互作用. 本实验中电针组、隔药灸组IL-1β,IL-6 mRNA表达显著下降,表明针灸可以抑制模型大鼠脾脏、结肠粘膜炎性细胞因子的基因表达,纠正异常的免疫功能,降低免疫细胞对炎症的反应性,从而有利于炎症的消除,组织的修复.
UC的发病过程不仅涉及到炎性细胞因子的作用,也有抗炎免疫因子(IL-4,IL-ra,IL-10等)的参与,是两者平衡失调的结果,针灸作用机制除抑制炎性细胞因子的表达外,是否激发抗炎免疫因子的参与,仍有待于进一步研究.
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图1 针灸对溃疡性结肠炎大鼠脾脏、结肠粘膜IL-1β,IL-6 mRNA的影响.
M:PCR标志(华美)由上至下为1543,994,695,515,377,237bp.
1,3,5,7分别为模型对照组、电针组、隔药灸组、正常组的结肠粘膜mRNA;2,4,6,8分别为模型对照组、电针组、隔药灸组、正常组的脾脏mRNA.
吴焕淦,男,1956-11-21生,浙江省仙居县人,1990年浙江中医学院硕士,1993年上海中医药大学博士,副教授,副所长,主要从事针灸免疫学研究,发表论文20篇.
*国家自然科学基金资助项目,No.39670899.
通讯作者 吴焕淦,200030,上海市针灸经络研究所.
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*Supported by the National Natural Science Foundation of China, No.39670899.
Correspondence to:Vice-Prof. WU Huan-Gan, Shanghai Institute of Acupuncture-Moxibustion and Meridians, 650 Wanping Nanlu, Shanghai 200030, China
Tel. +86*21*64395972
收稿日期 1998-07-07
4 参考文献
1 Kusugami K, Fukatsu A, Tanimoto M, Shinoda M, Haruta J, Kuroiwa A et al. Elevation of interleukin-6 in inflammatory bowel disease is macrophage-and epithelial cell-dependent. Dig Dis Sci, 1995;40(5):949-957
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2 Xia B, Guo HJ, Crusius JBA, Deng CH, Meuwissen SGM, Pena AS. In vitro production of TNFα, IL6 and sIL2R in Chinese patients with ulcerative colitis. WJG, 1998;4(3):252-255
3 吴焕淦,陈汉平,华雪桂,施征,张琳珊,陈及灵. 隔药灸治疗慢性腹泻的临床疗效及免疫学机理探讨. 中医杂志,1995;36(1):25-27
4 吴焕淦,陈汉平,廖柏松,施征,张琳珊. 隔药灸对大鼠实验性结肠炎免疫功能及β-内啡肽的影响. 中国针灸,1997;17(3):163-165
5 吴焕淦,陈汉平,王楠,赵粹英,陈及灵,施征 et al. 溃疡性结肠炎动物模型与隔药灸治疗作用的形态学研究. 中国针灸,1994;14(3):35-37
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6 Chomczynski P, Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chlorlform extraction. Anal Biochem, 1987;162(1):156-159
7 Murphy PG, Grondin J, Altares M, Richardson PM. Induction of interleukin-6 in axotomized sensory neurons. J Neurosci, 1995;15(7):5130-5132
8 Mitsuyama K, Toyonaga A, Sasaki E, Ishida O, Ikeda H,Tsuruta O et al. Soluble interleukin-6 receptors in inflammatory bowel disease: relation to circulating interleukin-6. Gut, 1995;36(1):45-49
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9 Stevens C, Walz G, Singaram C, Lipman ML, Zanker B, Muggia A et al. Tumor necrosis factor-α, interleukin-1β, and interleukin-6, expression in inflammatory bowel disease. Dig Dis Sci, 1992;37(6):818-819
10 Hogaboam CM, Snider DP, Collins SM. Cytokine modulation of T-lymphocyte activation by intestinal smooth muscle cells. Gastroenterology, 1997;112(6):1986-1994
11 Nassif A, Longo We, Mazuski JE, Vernava AM, Kaminski DL. Role of cytokines and platelet-activating fator inflammatory bowel disease. Dis Colon Rectum, 1996;39(2):219-220
12 Schreiber S, Raedler A, Stenson WF, MacDermott RP. The role of mucosal immune system in inflammatory bowel disease. Gastroenterol Clin North Am, 1992;21(2):469-471, 百拇医药