PEG-壳聚糖生物杂化胶束的制备及其体外动力学评价：以胆汁酸/槲皮素作为表面修饰剂负载CBD用于结肠癌治疗

《Archives of Biochemistry and Biophysics》：Development and In Vitro Kinetic Evaluation of PEG-Chitosan Biohybrid Micelles loading CBD with Bile Acid/Quercetin as Surface Modifiers for Colon Cancer Therapy

开发PEG-壳聚糖-胆汁酸-槲皮素生物混合微胶粒系统，通过表面修饰实现结肠癌靶向递送，增强CBD疗效与稳定性。SEM/TEM显示微胶粒结构均匀，XRD证实无结晶，包封效率77.3%。体外实验表明微胶粒剂量依赖性抑制HT29、HCT116、Caco-2细胞增殖（IC50分别为9.87/17.11/20.02 μM），激活caspase-3/7，上调Bax表达，下调Bcl-2表达，协同效应优于游离CBD。pH依赖性释放实验显示胆汁酸释放最快（pH1.2），槲皮素次之（pH7.4），证实多机制控释特性。该技术为降低CBD系统毒性提供新方案，临床转化潜力显著。

　　
colon cancer treatment through innovative biohybrid micelles has emerged as a significant research direction in nanomedicine. This study focuses on developing an oral delivery system combining cannabidiol (CBD) with bioactive components and nanomaterials to address current limitations of CBD-based therapies. The research team from East China University of Science and Technology presents a novel approach by integrating PEG-chitosan micelles with bile acid and quercetin, demonstrating synergistic effects that enhance therapeutic efficacy while minimizing adverse reactions.

The study begins by outlining the global health burden of colon cancer, projecting a 60% increase in new cases by 2030. Current treatments face challenges such as systemic toxicity, drug resistance, and low bioavailability of active ingredients like CBD. These issues motivate the development of targeted drug delivery systems, particularly for hydrophobic compounds with poor solubility.

The research methodology involves creating biohybrid micelles composed of PEG and chitosan as the core matrix, with bile acid and quercetin functionalized on the surface. This multi-component system aims to achieve three key objectives: improving CBD solubility and stability through polymer encapsulation, enhancing colon-specific targeting through bile acid receptors, and amplifying anticancer effects via quercetin's synergistic properties.

Structural characterization confirms the formation of uniform micelles with well-defined morphology (observed via SEM and TEM). The crystalline nature and purity of the micelles are verified through XRD and HPLC analyses. Encapsulation efficiency reaches 77.3% ± 2%, indicating effective drug loading. Thermal degradation profiles (TGA) and Fourier-transform infrared spectroscopy (FTIR) validate the structural integrity and chemical compatibility of the components.

Key findings reveal dose-dependent cell death suppression across three colon cancer cell lines (HCT116, HT29, Caco-2) with IC50 values ranging from 9.871 μM to 20.023 μM. This demonstrates improved efficacy compared to free CBD administration. Apoptosis induction is confirmed through increased caspase-3/7 activity and ELISA results showing upregulated Bax expression and downregulated Bcl-2 expression, which are critical markers of programmed cell death.

The pH-dependent drug release study (72 hours at pH 1.2, 6.8, 7.4) shows bile acid exhibiting the fastest release rate, followed by quercetin and CBD. This controlled release pattern aligns with the gastrointestinal environment, ensuring sustained action in the colon while reducing systemic exposure.

Synergistic mechanisms are proposed through three synergistic effects:
1. **Targeted delivery** via bile acid-mediated FXR/TGR5 receptor recognition
2. **Stabilization** through PEG-chitosan polymer interaction enhancing micelle durability
3. **Therapeutic amplification** from quercetin's antioxidant and anti-inflammatory properties that enhance CBD's apoptotic pathways

The system demonstrates reduced toxicity by achieving therapeutic effects at lower doses (approximately 10% of conventional CBD requirements based on IC50 comparison). This is attributed to the improved bioavailability from encapsulation and the synergistic actions between CBD and quercetin.

Preclinical validation includes comprehensive in vitro testing across three cell lines with differential responses based on genetic and molecular profiles. The combination of mucoadhesive chitosan, pH-sensitive polymer PEG, and natural targeting ligands creates a multifunctional system addressing multiple therapeutic challenges.

The research provides a framework for future clinical trials by establishing:
- Optimal component ratios (PEG:chitosan: bile acid: quercetin)
- Stability parameters under gastrointestinal conditions
- Dose-response relationships for different cancer subtypes
- Mechanistic pathways involving apoptosis and cell cycle regulation

This work advances the field of cancer nanotherapy by demonstrating how natural bioactive components can be integrated with synthetic polymers to create smart drug delivery systems. The combination of receptor-mediated targeting, controlled release, and synergistic therapeutic effects represents a paradigm shift in colon cancer treatment strategies.

The study's contribution lies in bridging material science and pharmacology through innovative material design. By optimizing polymer-polymer interactions and natural ligand compatibility, the system achieves superior performance in controlled release, targeted delivery, and therapeutic efficacy compared to conventional CBD formulations.

Current limitations include the need for in vivo validation and optimization of production scalability. However, the established methodology provides a replicable platform for developing other biohybrid systems targeting gastrointestinal cancers. The results align with recent nanomedicine trends emphasizing multifunctional carriers and natural-therapeutic combinations.

Future directions suggested by the authors include:
1. Exploring different quercetin derivatives for enhanced bioavailability
2. Incorporating additional targeting ligands for multi-site targeting
3. Developing in vivo imaging protocols to track micelle distribution
4. Conducting preclinical pharmacokinetic studies to establish safety profiles

This research not only addresses the technical challenges of CBD delivery but also provides a template for combining multiple therapeutic strategies into a single delivery system. The integration of natural bioactive components with synthetic nanomaterials represents a promising approach for developing next-generation anticancer therapies with improved specificity and reduced toxicity.