University of Lille, College of Pharmacy, Lille, France; INSERM U1008, Controlled Drug Delivery Systems and Biomaterials, Lille, France.
INSERM U995, Digestive Inflammatory Diseases, Lille, France.
J Control Release. 2015 Jan 10;197:121-30. doi: 10.1016/j.jconrel.2014.11.006. Epub 2014 Nov 10.
The first proof of concept in vivo for a new type of microbiota-sensitive film coatings allowing for colon targeting is presented. The efficacy of these polysaccharide barriers to optimize drug release for the treatment of inflammation is demonstrated in an experimental colitis model with Wister rats. 5-Aminosalicylic acid (5-ASA) pellets were prepared by extrusion-spheronization and coated with Nutriose:ethylcellulose (EC) 1:4 or peas starch:ethylcellulose 1:2 blends. The pellets were mixed with standard chow, and the daily drug dose was 150mg/kg. For reasons of comparison, also commercially available Pentasa pellets and placebo pellets were studied. At day 3 after the beginning of the treatment, colitis was induced by intrarectal administration of trinitrobenzene sulfonic acid (TNBS). Animals were sacrificed on day 6. Macroscopic and histological evaluations of colitis were performed blindly. In addition, inflammatory markers were evaluated using ELISA and real-time PCR. Rats receiving TNBS and placebo pellets developed a severe colitis in the distal half of the colon. 5-ASA administered in the form of Pentasa pellets reduced macroscopic inflammation by only 5%. In contrast, the colon lesions were much less severe upon treatment with Nutriose:EC- and peas starch:EC-coated pellets: The macroscopic score was reduced by 25 and 24%, respectively. Decreases of 37 and 38% of the histological lesions confirmed the efficacy of these new colon targeting systems. Also, inflammatory markers (MPO, IL-1β mRNA, TNF mRNA) were significantly decreased in rats receiving Nutriose:EC- and peas starch:EC-coated pellets compared to Pentasa pellets. Furthermore, real-time PCR analysis indicated increased activation of the target receptor PPAR-γ and the HMGCS2 gene in rats upon administration of 5-ASA loaded Nutriose:EC- and peas starch:EC pellets compared to the commercial product. Also, HPLC-MS/MS analysis of plasma samples demonstrated that the level of the main metabolite of the drug (N-acetyl-5-ASA) was much lower upon administration of Nutriose:EC or peas starch:EC coated pellets compared to Pentasa pellets, indicating that undesired premature drug release in the upper gastrointestinal tract was more effectively hindered. In addition to the rat study, in vivo imaging of transgenic mice expressing the luciferase gene evidenced much more pronounced PPAR-γ activation upon 5-ASA administration in the form of Nutriose:EC-coated pellets versus Pentasa pellets. All these results clearly demonstrate the superiority of these microbiota-sensitive polysaccharide-based film coatings for colon targeting in vivo.
本文提出了一种新型的微生物敏感性薄膜涂层用于结肠靶向的概念验证。通过 Wister 大鼠实验性结肠炎模型，证明了这些多糖屏障优化药物释放治疗炎症的功效。5-氨基水杨酸（5-ASA）微丸采用挤出-滚圆法制备，并分别包衣 Nutriose：乙基纤维素（EC）1：4 或豌豆淀粉：EC 1：2 混合物。将微丸与标准饲料混合，每日药物剂量为 150mg/kg。出于比较的原因，还研究了市售的 Pentasa 微丸和安慰剂微丸。在治疗开始后第 3 天，通过直肠内给予三硝基苯磺酸（TNBS）诱导结肠炎。第 6 天处死动物。对结肠炎进行盲法宏观和组织学评估。此外，还通过 ELISA 和实时 PCR 评估了炎症标志物。接受 TNBS 和安慰剂微丸的大鼠在结肠远端的一半发展为严重的结肠炎。以 Pentasa 微丸形式给予的 5-ASA 仅使宏观炎症减少 5%。相比之下，用 Nutriose：EC 和豌豆淀粉：EC 包衣的微丸治疗时，结肠病变明显较轻：宏观评分分别降低了 25%和 24%。组织学病变减少 37%和 38%证实了这些新型结肠靶向系统的疗效。接受 Nutriose：EC 和豌豆淀粉：EC 包衣微丸的大鼠的炎症标志物（MPO、IL-1β mRNA、TNF mRNA）也显著降低与 Pentasa 微丸相比。此外，用 5-ASA 负载的 Nutriose：EC 和豌豆淀粉：EC 微丸给药后，实时 PCR 分析表明大鼠中靶受体 PPAR-γ 和 HMGCS2 基因的激活增加与商业产品相比。此外，对血浆样品的 HPLC-MS/MS 分析表明，与 Pentasa 微丸相比，在用 Nutriose：EC 或豌豆淀粉：EC 包衣的微丸给药后，药物的主要代谢物（N-乙酰-5-ASA）的水平低得多，表明在上消化道中过早释放药物，从而更有效地阻止了未被期望的药物释放。除了大鼠研究外，在表达荧光素酶基因的转基因小鼠体内成像中，与 Pentasa 微丸相比，以 Nutriose：EC 包衣的微丸形式给予 5-ASA 时，PPAR-γ 的激活更为明显。所有这些结果都清楚地表明，这些基于微生物敏感性多糖的薄膜涂层在体内结肠靶向方面具有优越性。
