Ibrahim Ibrahim M
Department of Pharmacology, Faculty of Medicine, King Abdulaziz University, Jeddah, SAU.
Cureus. 2023 Jan 11;15(1):e33636. doi: 10.7759/cureus.33636. eCollection 2023 Jan.
Various colon-targeted oral delivery systems have been explored so far to treat colorectal diseases, including timed-release systems, prodrugs, pH-based polymer coatings, and microflora-triggered systems. Among them, the microbially triggered system has gained attention. Among various oral colon-targeted delivery systems discussed, the polysaccharide-based colon-targeted delivery system has been found to be quite promising as polysaccharides remain unaffected by gastric as well as upper intestine milieu and are only digested by colonic bacteria upon reaching the colon. The major bottleneck associated with this delivery is that non-suitability of this system during the diseased state due to decrease in bacterial count at that time. This causes the failure of delivery system to release the drug even at colonic site as the polysaccharide matrix/coat cannot be digested properly due to lack of bacteria. The co-administration of probiotics is reported to compensate for the bacterial loss besides facilitating site-specific release. However, this research is also limited at the preclinical level. Hence, efforts are required to make this technology scalable and clinically applicable. This article entails in detail various oral colon-targeted delivery systems prepared so far, as well as the limitations and benefits of polysaccharide-based oral colon-targeted delivery systems.
到目前为止，人们已经探索了各种结肠靶向口服给药系统来治疗结直肠疾病，包括定时释放系统、前体药物、基于pH的聚合物包衣以及微生物触发系统。其中，微生物触发系统受到了关注。在讨论的各种口服结肠靶向给药系统中，基于多糖的结肠靶向给药系统已被发现很有前景，因为多糖不受胃和上肠道环境的影响，只有在到达结肠后才会被结肠细菌消化。与这种给药方式相关的主要瓶颈是，在疾病状态下，由于此时细菌数量减少，该系统不适用。这导致给药系统即使在结肠部位也无法释放药物，因为由于缺乏细菌，多糖基质/包衣无法被正确消化。据报道，联合使用益生菌除了有助于药物在特定部位释放外，还能弥补细菌数量的损失。然而，这项研究在临床前阶段也受到限制。因此，需要努力使这项技术具有可扩展性并适用于临床。本文详细介绍了迄今为止制备的各种口服结肠靶向给药系统，以及基于多糖的口服结肠靶向给药系统的局限性和优点。
