The transport of mercury ions across intestinal epithelial cells can be studied for toxicology assessments by using animal models and static cell cultures. However, the concepts do not reliably replicate conditions of the human gut microenvironment to monitor in situ cell physiology. As a result, the mechanism of mercury transport in the human intestine is still unknown.
Gut-on-a-chip integrated with sensors. a) Device fabrication process. b) Annotated device decomposition diagram. The top and bottom microchannels were separated by the porous membrane. Simultaneous integration of three-electrode sensors and an Ag/AgCl electrode for in situ detection of Hg(II) and TEER. c) Photograph of the gut-on-a-chip integrated with sensors. Credit: Microsystems & Nanoengineering (2023). DOI: 10.1038/s41378-022-00447-2 In a new report now published in Nature Microsystems and Nanoengineering, Li Wang and a research team in mechanical engineering and regenerative medicine in China developed a gut-on-a-chip instrument integrated with transepithelial electrical resistance (TEER) sensors and electrochemical sensors. They proposed to explore the dynamic concept to simulate the physical intestinal barrier and mirror biological transport and adsorption mechanisms of mercury ions. The scientists recreated the cellular microenvironment by applying fluid shear stress and cyclic mechanical strain. Wang and the team studied mercury adsorption and the physical damage caused by the toxic element on epithelial cells via the performance of electrochemical sensors after exposing them to intestinal cells growing under diverse concentrations of mercury mixed in the cell culture medium. The team noted the corresponding expression and upregulation of Piezo1 and DMT1 (divalent metal transporter), both mechanosensory ion channels and iron transporters respectively on the cell surface. Developing an intestinal model Mercury ions are non-biodegradable and can accumulate in the body at low concentrations to cause damage to major organs. Toxic mercury ions can interact with antioxidant components, DNA repair enzymes and proteins at the subcellular level to disrupt cell homeostasis and produce disordered cellular structure and function. While mercury adsorption occurs predominantly in the small intestine, high levels of mercury ingestion can cause internal bleeding…