Publications by authors named "Megumi Hato"

Long-chain acyl-CoA synthetase-1 (ACSL1), an enzyme that catalyzes the synthesis of long-chain acyl-CoA from the corresponding fatty acids, is believed to play essential roles in lipid metabolism. Structure activity relationship studies based on HTS hit compound 1 delivered the benzimidazole series as the first selective and highly potent ACSL1 inhibitors. Representative compound 13 exhibited not only remarkable inhibitory activity against ACSL1 (IC = 0.

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Non-alcoholic steatohepatitis (NASH) is a progressive form of non-alcoholic fatty liver disease (NAFLD) that may lead to liver cirrhosis or hepatocellular carcinoma. Here, we examined the diagnostic utility of tri-antennary tri-sialylated mono-fucosylated glycan of alpha-1 antitrypsin (AAT-A3F), a non-invasive glycobiomarker identified in a previous study of NASH diagnosis. This study included 131 biopsy-proven Japanese patients with NAFLD.

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Serum N-glycans have been reported to be potential diagnostic and therapeutic biomarkers for many diseases and conditions, such as inflammation, fibrosis, and cancer progression. We previously described the focused protein glycomic analysis (FPG) from gel-separated serum proteins. With this methodology, we sought novel glycan biomarkers for nonalcoholic steatohepatitis (NASH) and successfully identified some N-glycans that were significantly elevated in NASH patients compared to nonalcoholic fatty liver patients.

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Inhibited: N-acetylglucosamine (GlcNAc) derivatives with a fluorine atom at the C4 position (2-4) were synthesized, and their ability to inhibit cancer-cell growth was investigated. The administration of these 4F-GlcNAc derivatives to cells led to the unnatural sugar nucleotide 1. Furthermore, N-glycan profiles of cells were determined by using a glycoblotting-based enrichment analysis, which is suitable for high-throughput screenings for drug discovery.

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Objective: The process of N-glycosylation is involved in the pathogenesis of various diseases. However, little is known about the contribution of changes in N-glycans in osteoarthritis (OA). The aim of this study was to identify the alterations in N-glycans in human OA cartilage, to characterize the messenger RNA (mRNA) expression of N-glycan biosynthesis enzyme genes (N-glycogenes) in mouse articular chondrocytes during cartilage degradation, and to analyze the relationship between altered N-glycan patterns and mechanisms of cartilage degradation.

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HPLC/MS is now an essential method for the analysis of glycans and glycopeptides. A technique using ICATs is also becoming popular for their comparative/quantitative analysis based on MS signal intensities. However, the RP HPLC most often used causes "doublet" peaks of deuterium-labeled and nonlabeled peptides, which are well known for causing the chromatographic deuterium isotope effect.

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Recent progress in mass spectrometry has led to new challenges in glycomics, including the development of rapid glycan enrichment techniques. A facile technique for exploration of a carbohydrate-related biomarker is important because proteomics research targets glycosylation, a posttranslational modification. Here we report an "all-in-one" protocol for high throughput clinical glycomics.

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Altered N-glycosylation occurs in many diseases. In rheumatoid arthritis (RA), for example, reduction in galactose residues in IgG and an increase in fucose residues in alpha1-acid glycoprotein have been observed. To further analyse N-glycans in disease, we show N-glycan profiling from whole serum employing reversed phase high performance liquid chromatography/negative-ion mode by sonic spray ionization ion trap mass spectrometry with pyridylamination.

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alpha-Mannosidase IIx (MX) is an enzyme closely related to alpha-mannosidase II (MII), a key enzyme in N-glycan biosynthesis that catalyzes the first step in conversion of hybrid- to complex-type N-glycans in Golgi apparatus. Recently we generated MII/MX double knock-out mice and found that double nulls completely lack the complex-type N-glycans (Akama, T. O.

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