5-氨基水杨酸治疗结肠炎的抗氧化作用及对细胞因子表达的影响

目的探讨5-氨基水杨酸(5-ASA)灌肠治疗对三硝基苯磺酸(TNBS)诱导大鼠结肠炎的抗氧化作用及对细胞因子表达的影响。方法建立TNBS结肠炎模型,给予5-ASA灌肠治疗,同时设正常对照组和模型组。于治疗后1、2周,评价结肠大体、组织学损伤及髓过氧化物酶(MPO)活性,检测超氧化物歧化酶(SOD)活性、丙二醛(MDA)水平,逆转录-多聚酶链反应(RT-PCR)检测结肠组织白细胞介素(IL)-1β和肿瘤坏死因子(TNF)-αmRNA表达水平。结果5-ASA灌肠治疗能明显降低结肠炎大鼠的大体、组织学评分及MPO活性(P<0.05),升高SOD活性(P<0.05),降低MDA水平(P<0.05),降低IL-1β和TNF-α表达水平(P<0.05)。结论5-ASA灌肠治疗TNBS诱导的大鼠结肠炎疗效显著,其机制与抗氧化作用及抑制IL-1β和TNF-α的表达有关。     

同型半胱氨酸调控MEK-ERK-MLCK通路影响结肠炎大鼠肠黏膜通透性的实验研究

目的探讨同型半胱氨酸(homocysteine,Hcy)是否通过调控MEK-ERK-MLCK通路影响结肠炎大鼠肠黏膜通透性的机制。方法 SD大鼠分为4组,A组为正常对照组(NS皮下注射+NS灌肠),B组为正常对照+Hcy注射组(Hcy皮下注射+NS灌肠),C组为TNBS模型组(NS皮下注射+TNBS灌肠),D组为TNBS模型+Hcy注射组(Hcy皮下注射+TNBS灌肠)。建立高Hcy血症的实验性结肠炎大鼠模型,实验结束时取大鼠结肠组织病理学检查,并进行结肠匀浆检测MPO活性,采用Western blot方法检测大鼠小肠组织中MEK、ERK、p-ERK、MLCK、p-MLCK的蛋白表达水平,采用RT-q PCR方法检测大鼠小肠组织中MLCK mRNA表达。结果与正常对照组及模型对照组相比,TNBS模型+Hcy皮下注射组大鼠DAI及HI评分增高,结肠匀浆MPO活性增高,小肠黏膜组织MEK、ERK、p-ERK、MLCK、p-MLCK蛋白表达水平增加,MLCK mRNA相对表达量增加。结论 Hcy增加实验性结肠炎大鼠肠黏膜通透性,可能与调控MEK-ERKMLCK信号通路有关。     

N-乙酰半胱氨酸对葡聚糖硫酸钠诱导的小鼠溃疡性结肠炎的保护作用

目的观察N-乙酰半胱氨酸(NAC)灌肠对小鼠急性溃疡性结肠炎的作用。方法5%葡聚糖硫酸钠(DSS)自由饮用7 d诱导小鼠急性溃疡性结肠炎,同时予以生理盐水(NS)、5-氨基水杨酸(5-ASA)、NAC保留灌肠,观察小鼠体重、粪便性状、隐血便血,计算疾病活动度(DAI)积分,检测结肠长度、结肠过氧化物酶(MPO)活性、血清过氧化物歧化酶(SOD)活力和丙二醛(MDA)含量及肠黏膜病理改变。结果NAC组小鼠隐血、便血、体重下降、DAI积分、病理改变等均好于模型组、NS组(P<0.05),与5-ASA组疗效相似。NAC组SOD活力高于模型组,MPO活性、MDA含量则低于模型组(P<0.05)。结论NAC对DSS诱导的小鼠急性溃疡性结肠炎黏膜损伤有保护作用,其机制可能与抗氧化应激有关。     

溃疡性结肠炎治疗药Olsalazine的药理学

水杨酸偶氮磺胺吡啶(Sulphasalazine,salicylazosulfapyridine,SASP)用于治疗溃疡性结肠炎已有40余年历史。已经提供了一年治疗400多万病人的记录。经SASP治疗的病人,其复发率下降了近1/3。近年来,明确了SASP具有急性抗炎作用,但其作用机制尚不明瞭。 SASP剂量为每日2～4g时,最终可导致10～15％的病人因副作用而停药。这些副作用的产生主要是由于SASP在肠道中偶氮键断裂,释放出磺胺吡啶所致;而偶氮键断裂所产生的5-氨基水杨酸(5-aminosalicylic acid,5-ASA)则是SASP的活性部分。 SASP 与5-ASA作保留灌肠治疗急性直、结肠炎的效果相同,而磺胺吡啶则无效。SASP的急性抗炎作用很可能是由于它在胃     

肠炎冲剂对溃疡性结肠炎模型大鼠的治疗作用

目的：研究肠炎冲剂对三硝基苯磺酸(TNBS)所致慢性溃疡性结肠炎模型大鼠的治疗作用。方法：TNBS的50％乙醇溶液一次性注人大鼠直肠，造成大鼠的慢性溃疡性结肠炎模型后，连续给药，观察腹泻率、死亡率，分别于连续给药3周及4周后麻醉处死动物，测定组织髓过氧化物酶(MPO)活力。地塞米松为阳性对照药。结果：地塞米松组动物症状减轻，但解剖学检查可见胸腺明显萎缩；连续给予不同剂量的肠炎冲剂药液(给药剂量为11．4、5．7、2．9g生药／kg体重)，各剂量组动物腹泻明显缓解，动物死亡率、腹泻率、结肠组织MPO活力明显降低，病理学检查或尸检可见结肠组织溃疡面积明显缩小，水肿缓解，坏死减轻，未见肠壁增厚。肠炎冲剂能显著缓解TNBS所致慢性溃疡性结肠炎症状，且未见地塞米松所致免疫器官萎缩的免疫抑制作用。结论：肠炎冲剂连续给药，对慢性溃疡性结肠炎模型大鼠治疗作用明显，并且未见地塞米松所致严重不良反应，是治疗慢性溃疡性结肠炎的较合适药物。     

HPLC同时测定乳癖消颗粒中三七皂苷R1、人参皂苷Rg1和人参皂苷Rb1的含量

目的观察4-氨基水杨酸钠(4-ASANa)结肠靶向微丸对溃疡性结肠炎大鼠的干预作用及其机制。方法采用三硝基苯磺酸(TNBS)法制备大鼠实验性溃疡性结肠炎模型,通过4-ASANa结肠靶向微丸干预14d,观察大鼠结肠大体形态损伤、组织学变化和白细胞介素-1B(IL-1B)、肿瘤坏死因子-α(TNF-α)、超氧化物歧化酶(SOD)、丙二醛(MDA)、髓过氧化物酶(MPO)等指标的变化。结果4-ASANa结肠靶向微丸能减轻溃疡性结肠炎的病理损伤,显著降低溃疡性结肠炎大鼠血清IL-1B和TNF-a含量,差异具有统计学意义(P<0.05),降低结肠组织中MDA和MPO含量,而提高SOD活性,差异具有统计学意义(P<0.05),对化学因素引起的结肠炎有较好的治疗作用。结论4-ASANa结肠靶向微丸对TNBS诱导的大鼠结肠炎具有治疗作用,抑制IL-1B和TNF-a的增殖和表达,减轻自由基的损害可能是作用机制之一。     

4-氨基水杨酸麦芽糖苷盲结肠定位给药系统的体外评价

目的:研究4-氨基水杨酸(4-ASA)麦芽糖苷(Mal)的体外盲结肠定位释药特征。方法:采用高效液相色谱法,以4-ASA的累积释放率为指标,分别考察4-ASA-Mal(相当于250μg/ml的4-ASA)在不同p H(1.2、6.8、7.4)缓冲液、正常大鼠和溃疡性结肠炎模型大鼠不同部位(胃、小肠、盲肠、结肠)内容物液中的释药行为。结果:4-ASA-Mal在不同p H缓冲液中几乎不释放;在正常和模型大鼠胃和小肠的内容物液中12 h的累积释放率均小于8%;在正常大鼠盲肠和结肠内容物液中12 h的累积释放率分别为55%和81%;在溃疡性结肠炎模型大鼠盲肠和结肠内容物液中12 h的累积释放率分别为55%和74%。结论:4-ASA-Mal可在体外盲结肠内容物液中定位大量释放4-ASA,具有盲结肠靶向性。     

具备高同型半胱氨酸血症的实验性结肠炎模型的建立

目的建立具备高同型半胱氨酸血症(HHcy)的实验性结肠炎模型,初步探讨Hcy对结肠炎症损伤的影响。方法将SD大鼠分为4组:正常对照组(NS灌肠+皮下注射NS)、正常对照+Hcy注射组(NS灌肠+皮下注射Hcy)、TN-BS模型对照组(TNBS/乙醇灌肠+皮下注射NS)、TNBS模型+Hcy注射组(TNBS/乙醇灌肠+皮下注射Hcy)。以TN-BS/乙醇混合溶液(100 mg·kg-1TNBS加入等体积NS)灌肠1次制备结肠炎模型后,采用皮下注射同型半胱氨酸(0.03μmol·kg-1,每天2次,间隔8 h,连续30 d)造成HHcy模型。实验结束后通过高效液相荧光法(HPLC-FD)检测血浆和结肠粘膜Hcy水平,进行DAI评分并取结肠组织进行HE染色评分,结肠组织匀浆检测MPO活性。结果与正常对照组比较,TNBS模型对照组大鼠DAI和HI评分增高(P<0.01),结肠组织MPO活性增高(P<0.01)。与TNBS模型对照组比较,TNBS模型+Hcy注射组大鼠血浆和结肠粘膜Hcy水平明显增高(P<0.01),DAI和HI评分明显增高(P<0.01),结肠组织MPO活性明显增高(P<0.01)。结论皮下注射同型半胱氨酸可以建立具备高同型半胱氨酸血症的实验性结肠炎模型,可用于探讨Hcy在结肠炎中的作用机制。     

肠包衣地塞米松脂质体壳聚糖胶囊对炎性结肠组织MPO活性的影响

目的评价肠包衣地塞米松(DSP)脂质体冻干剂壳聚糖胶囊对大鼠炎性结肠组织髓过氧化酶(MPO)活性的影响。方法用2,4,6-三硝基苯磺酸钠(TNBS)诱导大鼠结肠炎,建立反应结肠炎症程度的结肠组织MPO浓度的测定方法,观察口服各种DSP制剂对MPO的抑制程度。结果TNBS灌肠后d 5时MPO达到最高值;各种DSP制剂均有降低TNBS诱导的实验性大鼠结肠炎结肠组织MPO的效果,但DSP脂质体壳聚糖胶囊具有最好的抑制作用。结论肠包衣DSP脂质体冻干剂壳聚糖胶囊在治疗结肠炎中可能具有较大的应用前景,值得进一步开发研究。     

4-氨基水杨酸钠结肠靶向微丸对溃疡性结肠炎大鼠免疫机制影响

目的 观察 4-氨基水杨酸钠(4-ASANa)结肠靶向微丸对溃疡性结肠炎大鼠的干预作用及其机制。方法 采用三硝基苯磺酸(TNBS)法制备大鼠实验性溃疡性结肠炎模型,通过4-ASANa结肠靶向微丸干预14 d,观察大鼠结肠大体形态损伤、组织学变化和白细胞介素-1B(IL-1B)、肿瘤坏死因子-α(TNF-α)、超氧化物歧化酶(SOD)、丙二醛(MDA)、髓过氧化物酶(MPO)等指标的变化。结果 4-ASANa结肠靶向微丸能减轻溃疡性结肠炎的病理损伤,显著降低溃疡性结肠炎大鼠血清IL-1B和TNF-a含量,差异具有统计学意义(P<0.05),降低结肠组织中MDA和MPO含量,而提高SOD活性,差异具有统计学意义(P<0.05),对化学因素引起的结肠炎有较好的治疗作用。结论 4-ASANa结肠靶向微丸对TNBS诱导的大鼠结肠炎具有治疗作用,抑制IL-1B和TNF-a的增殖和表达,减轻自由基的损害可能是作用机制之一。     

Validation of a pharmacokinetic model of colon-specific drug delivery and the therapeutic effects of chitosan capsules containing 5-aminosalicylic acid on 2,4,6-trinitrobenzenesulphonic acid-induced colitis in rats

A pharmacokinetic model of colon-specific drug delivery developed in a previous study has been validated by use of 5-aminosalicylic acid (5-ASA) as a model anti-inflammatory drug. The simulation curves obtained from the pharmacokinetic model were in good agreement with experimental data obtained after oral administration of 5-ASA-containing chitosan capsules. The concentrations of 5-ASA in the large intestinal mucosa after drug administration were higher than after administration of the drug in carmellose suspension. We then attempted colon-specific delivery of an anti-ulcerative colitis drug, in chitosan capsules, to accelerate healing of 2,4,6-trinitrobenzenesulphonic acid sodium salt (TNBS)-induced colitis in rats. To confirm this therapeutic model, salazosulphapyridine (SASP), a commercially available 5-ASA prodrug, was used as positive control. Colonic injury and inflammation were assessed by measuring myeloperoxidase activity and visual assessment (damage score), respectively. Because SASP is effective against TNBS-induced colitis in rats, use of the SASP-sensitive TNBS-induced colitis model validated the therapeutic effects of 5-ASA-containing chitosan capsules, which were significantly better than those of a suspension of the drug in carmellose. These findings suggest that our pharmacokinetic model of colon-specific drug delivery can accurately evaluate this colon-specific delivery system and that 5-ASA-containing chitosan capsules are more effective than other 5-ASA formulations for treatment of TNBS-induced colitis in rats.     

肠安康新组方抗溃疡性结肠炎大鼠的机制研究

目的研究肠安康新组方抗溃疡性结肠炎(UC)大鼠可能的作用机制。方法制备三硝基苯磺酸(TNBS)/乙醇诱导溃疡性结肠炎(UC)大鼠模型,动物随机分为9组:正常对照组、模型对照组、柳氮磺胺吡啶(SASP)组、肠安康新组方口服给药组(1.12、0.56、0.28 g.kg-1)、肠安康新组方结肠定位给药组(1.12、0.56、0.28 g.kg-1)。造模后24 h开始给药,每天1次,连续给药7 d,从造模开始至实验结束共9d。实验结束后紫外分光光度法测诱导型一氧化氮合酶(iN-OS)活性、一氧化氮(NO)含量,ELISA法测白介素-8(IL-8)含量,免疫组化法检测c-Jun表达。结果与模型组相比,肠安康新组方各给药组均可改善升高的iNOS、NO、IL-8、c-Jun。结论肠安康新组方抗UC作用可能与抑制炎症因iN-OS、NO、IL-8的产生和c-Jun的激活有关。     

冬凌草甲素片对醋酸诱导的小鼠溃疡性结肠炎的治疗作用

目的考察冬凌草甲素片口服给药对醋酸诱导的小鼠溃疡性结肠炎的治疗作用。方法醋酸诱导的溃疡性结肠炎小鼠分别给予不同剂量的冬凌草甲素片灌胃给药,给药7 d后,考察冬凌草甲素片对溃疡性结肠炎小鼠病变活动(体质量、便潜血及粪便性状)的影响,以及对结肠病理组织学变化,结肠髓过氧化物酶活性及胸腺和脾脏指数的影响。结果冬凌草甲素片口服给药可剂量依赖性的降低结肠炎小鼠的病变活动、减轻结肠炎症、降低髓过氧化物酶活性,改善免疫器官脏器指数,以冬凌草甲素片高剂量给药组的作用更为显著。结论高剂量冬凌草甲素片口服给药对醋酸诱导的小鼠溃疡性结肠炎具有治疗作用,其机制可能与冬凌草甲素的抗炎和免疫调节作用有关。     

Colon-specific delivery of budesonide with azopolymer-coated pellets: therapeutic effects of budesonide with a novel dosage form against 2,4,6-trinitrobenzenesulphonic acid-induced colitis in rats.

The objective of this study was to achieve colon-specific delivery of budesonide using azopolymer-coated pellets and to accelerate healing of 2,4,6-trinitrobenzenesulphonic acid sodium salt (TNBS)-induced colitis in rats. After oral administration of azopolymer-coated pellets containing budesonide, a significant increase was observed in the therapeutic effects of the drug accompanied by a decrease in its systemic adverse effects when compared with oral administration in saline or rectal administration by enema. In addition, with the use of the colon-specific oral dosage form the dose of budesonide could be reduced. These results suggested that azopolymer-coated pellets may be a useful dosage form for the colon-specific delivery of budesonide as an anti-inflammatory steroid drug to bring about the healing of TNBS-induced colitis in rats.     

Evaluation of 5-aminosalicyltaurine as a colon-specific prodrug of 5-aminosalicylic acid for treatment of experimental colitis.

We previously reported that 5-aminosalicyltaurine (taurine-conjugated 5-ASA, 5-ASA-Tau) showed a potential as a colon-specific prodrug of 5-aminosalicylic acid (5-ASA) by in vitro evaluation. In this report, we in vivo-evaluated 5-ASA-Tau as a colon-specific prodrug for treatment of experimental colitis. Taurine conjugation of 5-ASA greatly reduced absorption of 5-ASA from the intestine. Oral administration of taurine-conjugated 5-ASA not only increased the colonic delivery efficiency of 5-ASA but also decreased the systemic absorption of free 5-ASA as compared with that of 5-ASA and, moreover, taurine is similarly effective to known colon-specific carriers for 5-ASA, glycine and aspartic acid, suggesting that taurine conjugation is an efficient way to increase the therapeutic effect and to reduce the adverse effects of 5-ASA. Intracolonic treatment with combined 5-ASA/taurine additively ameliorated TNBS-induced colitis rats indicating that taurine acted as not only a promoiety but also a therapeutically active agent. Furthermore, 5-ASA-Tau is slightly more effective than sulfasalazine in alleviating the colonic inflammation induced by TNBS. Taken together, our data suggest that 5-ASA-Tau is a potential colon-specific prodrug of 5-aminosalicylic acid with improved therapeutic activity against inflammatory bowel disease.     

氧化苦参碱对结肠炎模型大鼠结肠黏膜NOD2与TNF-α的影响

目的研究NOD2在实验性大鼠结肠炎发病机制中的作用,探讨氧化苦参碱对实验性大鼠结肠炎的治疗作用及其机制。方法将32只SD大鼠随机分为4组：对照组、模型组、美沙拉嗪组和氧化苦参碱组,每组8只。除对照组外,其余均采用三硝基苯磺酸造模。氧化苦参碱组给予苦参素注射液肌内注射,美沙拉嗪组给予美沙拉嗪纯化水溶液灌胃,模型组肌内注射等体积0.9%氯化钠注射液,共15 d。观察大鼠结肠黏膜大体形态及组织病理评分,并用免疫组织化学法检测大鼠结肠黏膜NOD2蛋白表达,酶联免疫吸附法检测实验大鼠结肠黏膜α肿瘤坏死因子（TNF α）表达。结果与对照组比较,模型组大鼠结肠黏膜NOD2蛋白、TNF α表达均显著升高（P＜0.01）;与模型组比较,美沙拉嗪组、氧化苦参碱组大鼠结肠黏膜NOD2蛋白、TNF α表达均显著降低（P＜0.01,P＜0.05）。结论结肠黏膜NOD2蛋白过度表达、TNF α分泌增多参与了溃疡性结肠炎的发生发展过程,而氧化苦参碱可以通过抑制NOD2蛋白过度表达、降低TNF α分泌起到减轻结肠黏膜炎症和保护结肠黏膜的作用。     

N,N'-Bis(5-aminosalicyl)-L-cystine is a potential colon-specific 5-aminosalicylic acid prodrug with dual therapeutic effects in experimental colitis

To evaluate N,N'-bis(5-aminosalicyl)-L-cystine (5-ASA-Cys) as a potential colon-specific 5-aminosalicylic acid prodrug with dual therapeutic effects in experimental colitis, the pharmacokinetics and therapeutic activity were investigated after oral administration of 5-ASA-Cys and amelioration of experimental colitis was compared after rectal administration of 5-aminosalicylic acid (5-ASA) and/or cysteine. In addition, the gluthathione (GSH) level in the inflamed colonic tissue was examined after administration of cysteine or 5-ASA-Cys. Oral administration of 5-ASA-Cys delivered much greater amount of 5-ASA to the large intestine and excreted lower amount of 5-ASA via urine than that of free 5-ASA. Oral administration of 5-ASA-Cys ameliorated experimental colitis of rats induced by TNBS, which was more effective than that of sulfasalazine. Although cysteine administered rectally was not significantly effective, intracolonic treatment with both 5-ASA and cysteine showed a synergic effect in alleviating the rat colitis. Furthermore, not only 5-ASA-Cys administered orally but also cysteine administered rectally increased the glutathione level in the inflamed colonic tissue. Taken together, these results suggest that 5-ASA-Cys is a potential colon specific 5-ASA prodrug with dual therapeutic effects on experimental colitis and cysteine modulation of the glutathione level may be relevant to the dual effects of the prodrug.     

Protective effect of taurohyodeoxycholic acid from Pulvis Fellis Suis on trinitrobenzene sulfonic acid induced ulcerative colitis in mice

Ulcerative colitis is a nonspecific inflammatory disorder characterized by oxidative and nitrosative stress, leucocyte infiltration and up-regulation of pro-inflammatory cytokines. The aim of this study is to evaluate the effect of taurohyodeoxycholic acid (THDCA) isolated from Pulvis Fellis Suis on acute ulcerative colitis model induced by trinitrobenzene sulfonic acid (TNBS) in mice. The efficacy of THDCA was studied by macroscopical and histological scoring systems as well as myeloperoxidase (MPO) activity. Serum levels, including tumor necrosis factor (TNF)-α and interleukin (IL)-6 were assayed by enzyme-linked immunoassay. The expression of cyclooxygenase (COX)-2 in the colons was assessed by immunohistochemical analysis. Treatment with THDCA in doses of 25, 50 and 100 mg/kg/day and sulfasalazine in a dose of 500 mg/kg/day used as reference for 7 consecutive days after the induction of colitis, significantly decreased colonic MPO activity, TNF-α, IL-6 serum levels and the expression of COX-2 in colon compared with TNBS induced ulcerative colitis model group. Moreover, THDCA attenuated the macroscopic colonic damage and the histopathological changes induced by TNBS. All the effects of these parameters were comparable to that of the standard sulfasalazine, especially at the highest dose level. The results suggested that THDCA from Pulvis Fellis Suis has a protective effect in TNBS-induced ulcerative colitis which might be due to its anti-inflammatory activities, and that it may have therapeutic value in the setting of inflammatory bowel disease.     

葡萄籽原花青素对复发性结肠炎大鼠血清抗氧化能力及NO含量的影响

目的：观察葡萄籽原花青素（GSPE）对复发性结肠炎大鼠血清抗氧化能力及NO含量的影响,初步探讨葡萄籽原花青素治疗复发性结肠炎的作用机制。方法：直肠给予雄性Wistar大鼠80mg/kg2,4,6-三硝基苯磺酸（TNBS）/50%乙醇溶液复制结肠炎模型,在第16天时,用30mg/kgTNBS/50%乙醇溶液诱导结肠炎复发的模型。大鼠第二次致炎24h后,分别应用GSPE低、中、高剂量（100、200、400mg/kg）灌胃对其进行治疗,并以柳氮磺吡啶（SASP,500mg/kg）作为阳性对照。连续给药7d后处死所有大鼠,取结肠标本评价结肠湿重指数,生化法检测血清中髓过氧化物酶（MPO）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）和一氧化氮合酶（iNOS）活力及丙二醛（MDA）、谷胱甘肽（GSH）和NO含量。结果：与模型对照组比较,GSPE各剂量组大鼠体重下降程度较轻（P〈0.05或P〈0.01）,结肠湿重指数明显降低（P〈0.05或P〈0.01） 大鼠血清中MPO和iNOS活力及MDA和NO含量均明显降低（P〈0.05或P〈0.01） 大鼠血清中SOD和GSH-Px活力及GSH含量明显升高（P〈0.05或P〈0.01）。结论：GSPE可能通过提高复发性结肠炎大鼠血清抗氧化能力,抑制NO生成,来减轻复发性结肠炎炎症反应。