Biology subjects

Furukawa, A.

Publications and source records attributed to Furukawa, A..

4 recordsLinked to original sources

bioRxiv2026

Oxidized EGCG redirects α-synuclein aggregation through shear-selected interactions

-Synuclein (Syn) aggregation is central to Parkinson's disease pathology, and the green-tea polyphenol epigallocatechin gallate (EGCG) has been studied as an inhibit fibril formation. However, EGCG autoxidation and analyses under static, non-fibrillating conditions have obscured whether activity arises from EGCG itself or oxidized species and which interactions persist during Syn assembly. Here we combine HPLC, LC-MS, TEM and solution NMR to compare unoxidized and oxidized EGCG (oxEGCG), while Rheo-NMR monitors Syn during shear-promoted assembly. Unoxidized EGCG showed no detectable binding under static, reducing conditions, whereas oxEGCG bound Syn, inhibited fibrillation and remodeled fibrils. Under shear flow, many oxEGCG-dependent perturbations partially reverted toward free Syn, whereas interactions near the NAC-C-terminal boundary were preferentially retained, coinciding with formation of oligomers and short, thick fibrils. These findings identify oxidation state and flow as determinants of EGCG action on Syn and show that Rheo-NMR distinguishes interactions that persist during shear-promoted assembly.

biochemistry↗

bioRxiv2026

An integrated Rheo-NMR platform for real-time, site-specific kinetic analysis of amyloid formation

Amyloid fibrils are protein aggregates associated with neurodegenerative diseases. Their formation proceeds through protein- and condition-dependent microscopic pathways that can generate structurally and biologically distinct aggregates, yet these pathways are inferred from ensemble-averaged measurements. Amyloid formation is often slow under quiescent conditions, prompting agitation. However, conventional agitation precludes simultaneous high-resolution solution nuclear magnetic resonance (NMR) spectroscopy, limiting site-specific kinetic analysis of microscopic aggregation pathways. Here we present an integrated Rheo-NMR platform combining controlled shear flow, time-resolved NMR spectroscopy and mechanistic kinetic modeling to quantify site-specific amyloid-formation kinetics in a single, continuously monitored reaction. Applied to -synuclein under dilute and polyethylene glycol (PEG)-induced liquid-liquid phase separation (LLPS) conditions, the method revealed environment-dependent redistribution of kinetic signatures associated with primary nucleation-elongation and secondary nucleation-elongation pathways across the sequence. The platform distinguishes changes in overall aggregation rates from differences in residue-specific kinetic profiles, providing a quantitative framework for dissecting environment-dependent amyloid formation.

biochemistry↗

bioRxiv2024

Tertiary lymphoid structure as a therapeutic target of Crohns disease: modulation by TNFα blockade

Inflammatory diseases, such as Crohns disease (CD), are primarily treated with therapies aimed at alleviating inflammation. Notably, biological agents like TNF inhibitors have transformed the management of these conditions. Previous research has indicated that TNF inhibitors affect the cells in the lamina propria. However, this study demonstrates that infliximab, a type of TNF inhibitor, reduces the presence of tertiary lymphoid structures (TLS) and alleviates inflammation of CD by targeting follicular dendritic cells and macrophages within these structures. TLS could also be a potential target for various biological agents used to treat inflammatory diseases beyond CD. Furthermore, our study suggests that the status of TLS may serve as a predictor for the response to TNF inhibitor treatment. Our research could pave the way for new treatment strategies and the advancement of personalized medicine for inflammatory diseases.

immunology↗

bioRxiv2021

Water droplet-in-oil digestion method for single-cell proteomics

Recent advances in single-cell proteomics highlight the promise of sensitive analyses in limited cell populations. However, technical challenges remain for sample recovery, throughput, and versatility. Here, we first report a water droplet-in-oil digestion (WinO) method based on carboxyl-coated beads and phase transfer surfactants for proteomic analysis using limited sample amounts. This method was developed to minimize the contact area between the sample solution and the container to reduce the loss of proteins and peptides by adsorption. This method increased protein and peptide recovery 10-fold as well as the number of quantified transmembrane proteins compared to an in-solution digestion (ISD) method. The proteome profiles obtained from 100 cells using the WinO method highly correlated with those from 10000 cells using the ISD method. We successfully applied the WinO method to single-cell proteomics and quantified 462 proteins. Using the WinO method, samples can be easily prepared in a multi-well plate, making it a widely applicable and suitable method for single-cell proteomics.

systems biology↗