[Construction of an enteritis chip model based on microfluidic technology and its application in the evaluation of...

To simulate the intestinal microenvironment and physiological structure, this study constructed the enteritis chip model via the microfluidic technology. Meanwhile, the Aloe vera polysaccharide copolymer (LDG@AMI) loaded with 5-aminosalicylic acid (5-AMI), the nanodrug LDG@AMI was synthesized, and its anti-inflammatory effects were evaluated through the enteritis chip model. In this study, a fluorescence microscopy was employed to measure the growth conditions of cells and the expression of intestinal barrier protein (ZO-1) and intestinal mucosa protein (WGA) in the enteritis chip. In addition, the morphology, size, and composition of LDG@AMI were measured via a transmission electron microscope, a nanoparticle size analyzer, and a Fourier-transform infrared (FT-IR) spectrometer, respectively. Subsequently, the swelling and drug release properties of LDG@AMI were evaluated by ultraviolet-visible (UV-Vis) spectroscopy. Furthermore, ELISA kits were used to quantify the levels of inflammatory factors including tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1 β (IL-1β) in the enteritis chip. The results indicated that the intestine chip cells exhibited good viability and normal expression of ZO-1, which implied the formation of intestinal barrier. After the treatment with sodium dextran sulfate (DSS), the chip showcased increased permeability, elevated expression level of hypoxia inducible factor-1α (HIF-1α), and significantly declined expression levels of ZO-1 and WGA, which suggested that the enteritis chip model was successfully constructed. LDG@AMI had a particle size of about 80 nm, a high swelling rate, and sustained release properties, accurately responding to the intestinal microenvironment. The LDG@AMI-treated enteritis chip showed higher expression levels of ZO-1 and WGA than the 5-AMI-treated group, which indicated that LDG@AMI possessed the excellent ability of repairing barriers. Compared with those in the normal intestine chip, the expression levels of TNF-α, IL-1β, and IL-6 in the enteritis chip significantly increased, further confirming that the enteritis chip model was successfully constructed. Interestingly, the LDG@AMI-treated enteritis chip showed the lower levels of TNF-α, IL-1β, and IL-6 than the untreated enteritis chip, which verified that LDG@AMI possessed excellent therapeutic effect on enteritis. We successfully construct a microfluidic technology-based enteritis chip model and further evaluate the anti-inflammatory effect of LDG@AMI, expanding new horizons for precise treatment of enteritis.