Biology subjects

Kahyo, T.

Publications and source records attributed to Kahyo, T..

3 recordsLinked to original sources

bioRxiv2024

Comparative analyses of adsorbed circulating proteins in the PMMA and PES hemodiafilters in patients on predilution online hemodiafiltration

Acute and chronic inflammation are common in patients with end-stage kidney disease (ESKD). So, the adsorption of pro-inflammatory cytokines by the hollow fiber has been expected to modify the inflammatory dysregulation in ESKD patients. However, it remains to be determined in detail what molecules of fiber materials can preferably adsorb proteins from the circulating circuit. We aimed this study to analyze directly the adsorbed proteins in the polymethyl methacrylate (PMMA) and polyethersulfone (PES) membranes in patients on predilution online hemodiafiltration (OL-HDF). To compare the adsorbed proteins in the PMMA and PES hemodiafilters membrane, we initially performed predilution OL-HDF using the PES (MFX-25Seco) membrane while then switched to the PMMA (PMF-A) membrane under the same condition in three patients. We extracted proteins from the collected hemodiafilters by extraction, then SDS-PAGE of the extracted sample, protein isolation, in-gel tryptic digestion, and nano-LC MS/MS analyses. The concentrations of adsorbed proteins from the PMMA and PES membrane extracts were 35.6{+/-}7.9 {micro}g/{micro}L and 26.1{+/-}9.2 {micro}g/{micro}L. SDS-PAGE analysis revealed distinct variations of adsorbed proteins mainly in the molecular weight between 10 to 25 kDa. By tryptic gel digestion and mass spectrometric analysis, the PMMA membrane exhibited higher adsorptions of {beta}2 microglobulin, dermcidin, retinol-binding protein-4, and lambda-1 light chain than those from the PES membrane. In contrast, amyloid A-1 protein was adsorbed more potently in the PES membrane. Western blot analyses revealed that the PMMA membrane adsorbed interleukin-6 (IL-6) approximately 5 to 118 times compared to the PES membrane. These findings suggest that PMMA-based OL-HDF therapy may be useful in controlling inflammatory status in ESKD patients.

pathology↗

bioRxiv2023

UBL3 interaction with α-synuclein is downregulated by silencing MGST3

Ubiquitin-like 3 (UBL3) is a membrane-anchored protein that has been discovered to function as a protein post-translational modifier, helping to sort proteins into small extracellular vesicles (sEVs). Aggregations of alpha-synuclein (-syn) are associated with the pathology of neurodegenerative diseases such as Parkinsons disease (PD). The aggregation and toxicity of -syn can be influenced by its interactions with specific proteins. Recently, the interactions between UBL3 and -syn was uncovered. It is believed to play a role in eliminating excess -syn from neurons, or in the spread of -syn pathology in the brain associated with neurodegenerative diseases. However, the regulator that can mediate the interaction between UBL3 and -syn remains unclear. In this study, we employed the split gaussian luciferase complementation assay and RNA interference (RNAi) technology to discover that QSOX2, HTATIP2, UBE3C, MGST3, NSF, HECTD1, SAE1 and ATG3 are involved in downregulating the interaction between UBL3 and -syn. Among these proteins, silencing MGST3 had the most significant impact on the UBL3--syn interaction (with a fold change log2 of less than - 1). MGST3 is a part of the antioxidant system, and silencing MGST3 is believed to contribute to oxidative stress. We used hydrogen peroxide (H2O2) to induce oxidative stress and observed its effect on the UBL3--syn interaction. Our finding showed that an 800M concentration of H2O2 could also downregulate this interaction. However, the effect of oxidative stress caused by 800M H2O2 on the UBL3--syn interaction did not be enhanced by silencing MGST3. In conclusion, the interaction between UBL3 and -syn is downregulated by silencing MGST3.

molecular biology↗

bioRxiv2023

UBL3 Interacts with Alpha-synuclein in Cells and the Interaction is Downregulated by the EGFR Pathway Inhibitor Osimertinib

Ubiquitin-like 3 (UBL3) acts as a post-translational modification (PTM) factor and regulates protein sorting into small extracellular vesicles (sEVs). sEVs have been reported as vectors for the pathology propagation of neurodegenerative diseases, such as -synucleinopathies. Alpha-synuclein (-syn) has been widely studied for its involvement in -synucleinopathies. However, it is still unknown whether UBL3 interacts with -syn, and is influenced by drugs or compounds. In this study, we investigated the interaction between UBL3 and -syn, and any ensuing possible functional and pathological implications. We found that UBL3 can interact with -syn by the Gaussia princeps based split luciferase complementation assay in cells and immunoprecipitation, while cysteine residues at its C-terminal, which are considered important as PTM factors for UBL3, were not essential for the interaction. The interaction was upregulated by 1-methyl-4-phenylpyridinium exposure. In drug screen results, the interaction was significantly downregulated by the treatment of osimertinib. These results suggest that UBL3 interacts with -syn in cells and be significantly downregulated by epidermal growth factor receptor (EGFR) pathway inhibitor osimertinib. Therefore, the UBL3 pathway may be a new therapeutic target for -synucleinopathies in the future.

molecular biology↗