Advances of microfluidic intestine-on-a-chip for analyzing anti-inflammation of food

Bioactivity and Bioavailability of Carotenoids Applied in Human Health: Technological Advances and Innovation

This article presents a groundbreaking perspective on carotenoids, focusing on their innovative applications and transformative potential in human health and medicine. Research jointly delves deeper into the bioactivity and bioavailability of carotenoids, revealing therapeutic uses and technological advances that have the potential to revolutionize medical treatments. We explore pioneering therapeutic applications in which carotenoids are used to treat chronic diseases such as cancer, cardiovascular disease, and age-related macular degeneration, offering novel protective mechanisms and innovative therapeutic benefits. Our study also shows cutting-edge technological innovations in carotenoid extraction and bioavailability, including the development of supramolecular carriers and advanced nanotechnology, which dramatically improve the absorption and efficacy of these compounds. These technological advances not only ensure consistent quality but also tailor carotenoid therapies to each patient's health needs, paving the way for personalized medicine. By integrating the latest scientific discoveries and innovative techniques, this research provides a prospective perspective on the clinical applications of carotenoids, establishing a new benchmark for future studies in this field. Our findings underscore the importance of optimizing carotenoid extraction, administration, bioactivity, and bioavailability methods to develop more effective, targeted, and personalized treatments, thus offering visionary insight into their potential in modern medical practices.

Establishment and evaluation of on-chip intestinal barrier biosystems based on microfluidic techniques

As a booming engineering technology, the microfluidic chip has been widely applied for replicating the complexity of human intestinal micro-physiological ecosystems in vitro. Biosensors, 3D imaging, and multi-omics have been applied to engineer more sophisticated intestinal barrier-on-chip platforms, allowing the improved monitoring of physiological processes and enhancing chip performance. In this review, we report cutting-edge advances in the microfluidic techniques applied for the establishment and evaluation of intestinal barrier platforms. We discuss different design principles and microfabrication strategies for the establishment of microfluidic gut barrier models in vitro. Further, we comprehensively cover the complex cell types (e.g., epithelium, intestinal organoids, endothelium, microbes, and immune cells) and controllable extracellular microenvironment parameters (e.g., oxygen gradient, peristalsis, bioflow, and gut-organ axis) used to recapitulate the main structural and functional complexity of gut barriers. We also present the current multidisciplinary technologies and indicators used for evaluating the morphological structure and barrier integrity of established gut barrier models in vitro. Finally, we highlight the challenges and future perspectives for accelerating the broader applications of these platforms in disease simulation, drug development, and personalized medicine. Hence, this review provides a comprehensive guide for the development and evaluation of microfluidic-based gut barrier platforms.

Gut-on-a-Chip for the Analysis of Bacteria-Bacteria Interactions in Gut Microbial Community: What Would Be Needed for Bacterial Co-Culture Study to Explore the Diet-Microbiota Relationship?

Bacterial co-culture studies using synthetic gut microbiomes have reported novel research designs to understand the underlying role of bacterial interaction in the metabolism of dietary resources and community assembly of complex microflora. Since lab-on-a-chip mimicking the gut (hereafter "gut-on-a-chip") is one of the most advanced platforms for the simulative research regarding the correlation between host health and microbiota, the co-culture of the synthetic bacterial community in gut-on-a-chip is expected to reveal the diet-microbiota relationship. This critical review analyzed recent research on bacterial co-culture with perspectives on the ecological niche of commensals, probiotics, and pathogens to categorize the experimental approaches for diet-mediated management of gut health as the compositional and/or metabolic modulation of the microbiota and the control of pathogens. Meanwhile, the aim of previous research on bacterial culture in gut-on-a-chip has been mainly limited to the maintenance of the viability of host cells. Thus, the integration of study designs established for the co-culture of synthetic gut consortia with various nutritional resources into gut-on-a-chip is expected to reveal bacterial interspecies interactions related to specific dietary patterns. This critical review suggests novel research topics for co-culturing bacterial communities in gut-on-a-chip to realize an ideal experimental platform mimicking a complex intestinal environment.

In Vitro Models of Biological Barriers for Nanomedical Research

Nanoconstructs developed for biomedical purposes must overcome diverse biological barriers before reaching the target where playing their therapeutic or diagnostic function. In vivo models are very complex and unsuitable to distinguish the roles plaid by the multiple biological barriers on nanoparticle biodistribution and effect; in addition, they are costly, time-consuming and subject to strict ethical regulation. For these reasons, simplified in vitro models are preferred, at least for the earlier phases of the nanoconstruct development. Many in vitro models have therefore been set up. Each model has its own pros and cons: conventional 2D cell cultures are simple and cost-effective, but the information remains limited to single cells; cell monolayers allow the formation of cell–cell junctions and the assessment of nanoparticle translocation across structured barriers but they lack three-dimensionality; 3D cell culture systems are more appropriate to test in vitro nanoparticle biodistribution but they are static; finally, bioreactors and microfluidic devices can mimicking the physiological flow occurring in vivo thus providing in vitro biological barrier models suitable to reliably assess nanoparticles relocation. In this evolving context, the present review provides an overview of the most representative and performing in vitro models of biological barriers set up for nanomedical research.

Microfluidics-assisted electrospinning of aligned nanofibers for modeling intestine barriers

During electrospinning, the fibers deposited on the collector are usually randomly oriented in a disordered form. Researchers hope to generate periodic structures to expand the application of electrospinning, including improving the sensing properties of electronic and photonic devices, improving the mechanical properties of solid polymer composites and directional growth of human tissues. Here, we propose a technique to control the preparation of aligned foodborne nanofibers by placing dielectric polymers on microfluidic devices, which does not require the use of metal collectors. This study was conducted by introduced PEDOT:PSS polymer as a ground collector to prepare aligned foodborne nanofibers directly on the microfluidic platform. The fluidity of the electrolytic polymer collector makes it possible to shape the grounding collector according to the shape of the microcavity, thus forming a space adjustable nanofiber membrane with a controllable body. The simplicity of dismantling the collector also enables it extremely simple to obtain a complete electrospun fiber membrane without any additional steps. In addition, nanofibers can be easily stacked into a multi-layer structure with controllable hierarchical structures. The Caco-2 cells that grow on the device formed a compact intestinal epithelial layer that continuously expresses the tightly bound protein ZO-1. This intestinal barrier, which selectively filters small molecules, has a higher level of TEER, reproducing intestinal filtration functions similar to those of in vivo models. This method provides new opportunities for the design and manufacture of various tissue scaffolds, photonic and electronic sensors.

Microfluidic Fabrication of pH-Responsive Nanoparticles for Encapsulation and Colon-Target Release of Fucoxanthin

Improving the stability of fucoxanthin in the gastrointestinal tract is an important approach to enhance its oral bioavailability. The study proposed a new microfluidic device allowing for the synthesis of a structurally well-defined nanoscale delivery system with a uniform size for encapsulation and colon-target release of fucoxanthin. The rapid mixing in the microfluidic channel ensured that the mixing time was shorter than the aggregation time, thus realizing the controllable control of the coprecipitation of fucoxanthin and shellac polymer. In vitro digestion tests showed that a pH stimulus-responsive release of fucoxanthin from FX/SH NPs was observed under alkaline pH conditions. The fluorescence colocalization imaging indicated that FX/SH NPs did not affect the intestine function and had a protective effect on Caco-2 cells damaged by H₂O₂ by enhancing their antioxidant capacity. Overall, this work illustrated the promise of using a microfluidic approach to fabricate the biomimetic nanodelivery system for better biocompatibility and targeting efficacy.

Evaluation of Hybrid Vesicles in an Intestinal Cell Model Based on Structured Paper Chips

Cell culture-based intestinal models are important to evaluate nanoformulations intended for oral drug delivery. We report the use of a floating structured paper chip as a scaffold for Caco-2 cells and HT29-MTX-E12 cells that are two established cell types used in intestinal cell models. The formation of cell monolayers for both mono- and cocultures in the paper chip are confirmed and the level of formed cell-cell junctions is evaluated. Further, cocultures show first mucus formation between 6-10 days with the mucus becoming more pronounced after 19 days. Hybrid vesicles (HVs) made from phospholipids and the amphiphilic block copolymer poly(cholesteryl methacrylate)-block-poly(2-carboxyethyl acrylate) in different ratios are used as a representative soft nanoparticle to assess their mucopenetration ability in paper chip-based cell cultures. The HV assembly is characterized, and it is illustrated that these HVs cross the mucus layer and are found intracellularly within 3 h when the cells are grown in the paper chips. Taken together, the moist three-dimensional cellulose environment of structured paper chips offers an interesting cell culture-based intestinal model that can be further integrated with fluidic systems or online read-out opportunities.

Advances on colorectal cancer 3D models: The needed translational technology for nanomedicine screening

Colorectal cancer (CRC) is a heterogeneous and molecularly complex disease, associated with high mortality worldwide, exposing the urgent need for novel therapeutic approaches. Their development and translation to the clinic have been hampered, partially due to the absence of reliable cellular models that resemble key features of the human disease. While traditional 2D models are not able to provide consistent and predictive responses about the in vivo efficiency of the formulation, animal models frequently fail to recapitulate cancer progression and to reproduce adverse effects. On its turn, multicellular 3D systems, by mimicking key genetic, physical and mechanical cues of the tumor microenvironment, constitute a promising tool in cancer research. In addition, they constitute more physiological and relevant environment for anticancer drugs screening and for predicting patient's response towards personalized approaches, bridging the gap between simplified 2D models and unrepresentative animal models. In this review, we provide an overview of CRC 3D models for translational research, with focus on their potential for nanomedicines screening.