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Biology subjects

Mio, M.

Publications and source records attributed to Mio, M..

2 recordsLinked to original sources

Quantum Dot-Based Non-invasive Monitoring of Sinusoidal Endothelial Scavenger Function in Steatohepatitis

Metabolic dysfunction-associated steatotic liver disease (MASLD) and its progressive form, metabolic dysfunction-associated steatohepatitis (MASH), represent urgent medical challenges. Current non-invasive assessments rely on serum indices or tissue stiffness, and none visualizes functional changes within the liver, hindering drug discovery and patient management. In this study, we developed a non-invasive technique using semiconductor quantum dots, as blood-borne foreign particle mimics, to evaluate the scavenger function of liver sinusoidal endothelial cells (LSECs) via near-infrared optical imaging. Progression from MASLD to MASH induced a significant decline in the scavenger capability of LSECs, resulting in a marked reduction of intrahepatic quantum dot retention. Mechanistically, we demonstrated that quantum dots are recognized and internalized by scavenger receptor class A (SR-A) on LSECs, and that SR-A-mediated uptake progressively diminishes with increasing MASH severity. Crucially, quantum dot retention levels significantly correlated with both the progression and regression of MASH pathology. These findings demonstrate that quantum dot-based optical evaluation of LSEC scavenger function offers a highly sensitive, non-invasive diagnostic platform for staging MASH and assessing therapeutic efficacy.

bioengineering↗

Agonist and antagonist diverted twisting motions of single TRPV1 channel

Transient receptor potential vanilloid type 1 (TRPV1) channels are activated by heat, vanilloids, and extracellular protons. Cryo-EM has revealed various conformations of TRPV1, and these structures suggest an intramolecular twisting motion in response to ligand binding. However, limited experimental data support this observation. Here we analyzed the intramolecular motion of TRPV1 using diffracted X-ray tracking (DXT). DXT analyzes trajectories of Laue spots generated from attached gold nanocrystals, and provides picometer spatial and microsecond time scale information about intramolecular motion. We observed that both an agonist and a competitive antagonist evoked rotating bias in TRPV1, though these biases were in opposing directions. Furthermore, the rotational bias generated by capsaicin was reversed between the wild type and the capsaicin-insensitive Y511A mutant. Our findings bolster the understanding of the mechanisms used activation and modulation of TRP channels, and this knowledge can be exploited for pharmacological usage such as inhibitor design.

biophysics↗