School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, 311402, China.
School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, 311402, China.
Phytomedicine. 2022 Jul;101:154110. doi: 10.1016/j.phymed.2022.154110. Epub 2022 Apr 16.
Renal fibrosis is the final common pathological feature of various chronic kidney diseases (CKD). Despite recent advances, development of new treatments strategy is needed. Emodin (EMO), an important ingredient of Chinese medicine, rhubarb (Polygonaceae Rheum palmatum l.), has been reported to inhibit the development of renal fibrosis effectively. However, the poor oral bioavailability of EMO and the insufficient monotherapy therapy compromise its efficacy.
In order to enhance renal fibrosis therapy of emodin, an innovative combination therapy based on deoxycholic acid-chitosan coated liposomes (DCS-Lips) and in situ colonic gel (IGE) was developed.
For one, the DCS-Lips were prepared via electrostatic interaction by mixing anionic conventional Lips with cationic DCS, deoxycholic acid conjugated on the backbone of chitosan. The cellular uptake of FITC-labeled DCS-Lips in Caco-2 cell monolayer was evaluated by CLSM and flow cytometry, respectively. Permeability study was carried out using Caco-2 cell monolayer. For another, EMO-loaded in situ colonic gel (EMO-IGE) was prepared by mixing EMO nanosuspensions and plain in situ gel, which was obtained by the cold method. The EMO-IGE was assessed for morphology, gelation temperature, viscosity and in vitro drug release. Finally, the therapeutic efficacy of the combination strategy, oral DCS-Lips formulations and in situ colonic gel, was evaluated in unilateral ureteral obstruction (UUO) rat model. Additionally, 16S rDNA sequencing was performed on rats faces to investigate whether the combination strategy improves the microbial dysbiosis in UUO rats.
The prepared DCS-Lips produced small, uniformly sized nanoparticles, and significantly enhanced the cellular uptake and in vitro permeability of EMO compared to non-coated liposomes. Moreover, the EMO-IGE was characterized by short gelation time, optimal gelling temperature, and excellent viscosity. In UUO model, the combination of DCS-Lips (gavage) and IGE (enema) attenuated renal fibrosis effectively. The results of 16S rDNA sequencing illustrated that IGE could restore the gut microbial dysbiosis of UUO rats.
Overall, the combination of DCS-Lips and EMO-IGE alleviated renal fibrosis effectively, resulting from the improved oral bioavailability of EMO by DCS-Lips and the restoration of gut microbiota by EMO-IGE, thus, presenting an innovative and promising potential for renal fibrosis treatment.
肾纤维化是各种慢性肾脏病（CKD）的共同终末病理特征。尽管最近有了进展，但仍需要开发新的治疗策略。大黄素（EMO）是中药大黄（蓼科大黄属掌叶大黄）的一种重要成分，已被报道能有效抑制肾纤维化的发展。然而，EMO 的口服生物利用度差和单一疗法不足限制了其疗效。
为了增强 EMO 的肾纤维化治疗效果，开发了一种基于脱氧胆酸-壳聚糖包被脂质体（DCS-Lips）和原位结肠凝胶（IGE）的创新联合治疗方法。
首先，通过将带负电荷的普通脂质体与带正电荷的 DCS（脱氧胆酸接枝在壳聚糖的主链上）混合，通过静电相互作用制备 DCS-Lips。通过共焦激光扫描显微镜（CLSM）和流式细胞术分别评估 FITC 标记的 DCS-Lips 在 Caco-2 细胞单层中的细胞摄取。通过 Caco-2 细胞单层进行渗透研究。其次，通过将 EMO 纳米混悬液与普通原位凝胶混合制备 EMO 原位结肠凝胶（EMO-IGE），原位凝胶通过冷法获得。对 EMO-IGE 的形态、胶凝温度、粘度和体外药物释放进行评价。最后，在单侧输尿管梗阻（UUO）大鼠模型中评价联合策略、口服 DCS-Lips 制剂和原位结肠凝胶的治疗效果。此外，对大鼠面部进行 16S rDNA 测序，以研究联合策略是否改善 UUO 大鼠的微生物失调。
所制备的 DCS-Lips 产生了小而均匀的纳米颗粒，与非包被脂质体相比，显著增强了 EMO 的细胞摄取和体外渗透性。此外，EMO-IGE 的特点是胶凝时间短、最佳胶凝温度和优异的粘度。在 UUO 模型中，DCS-Lips（灌胃）和 IGE（灌肠）的联合应用能有效减轻肾纤维化。16S rDNA 测序结果表明，IGE 可以恢复 UUO 大鼠的肠道微生物失调。
总之，DCS-Lips 和 EMO-IGE 的联合应用能有效减轻肾纤维化，这是由于 DCS-Lips 提高了 EMO 的口服生物利用度，EMO-IGE 恢复了肠道微生物群，为肾纤维化治疗提供了一种创新且有前景的潜在方法。
