Bioassay-guided fractionation of a MeOH extract of the rhizomes of Astilbe koreana (Saxifragaceae), using an in vitro protein tyrosine phosphatase 1B (PTP1B) inhibitory assay, resulted in the isolation of a new triterpene, 3alpha,24-dihydroxyolean-12-en-27-oic acid (4), along with four triterpenes, 3-oxoolean-12-en-27-oic acid (1), 3beta-hydroxyolean-12-en-27-oic acid (beta-peltoboykinolic acid; 2), 3beta-hydroxyurs-12-en-27-oic acid (3), and 3beta,6beta-dihydroxyolean-12-en-27-oic acid (astilbic acid; 5). Compounds 1-5 inhibited PTP1B with IC50 values of 6.8+/-0.5, 5.2+/-0.5, 4.9+/-0.4, 11.7+/-0.9, and 12.8+/-1.1 microM, respectively. Our results indicate that 3-hydroxyl group and a carboxyl group in this type of triterpenes may be required for the activity, while addition of one more hydroxyl group at C-6 or C-24 may be responsible for a loss of activity. Thus, compounds 2 and 3 which possess only one hydroxyl group at C-3 and a carboxyl group at C-27 could be potential PTP1B inhibitors.
Mussels and tubeworms have evolved similar adhesive systems to cope with the hydrodynamics of intertidal environments. Both secrete adhesive proteins rich in DOPA, a post-translationally modified amino acid playing essential roles in their permanent adhesion. DOPA is produced by the hydroxylation of tyrosine residues by tyrosinase enzymes, which can also oxidize it further into dopaquinone.
Introduction: Neutrophil autophagy and neutrophil extracellular trap (NET) formation are closely related to asthma pathogenesis. Src homology domain 2-containing protein tyrosine phosphatase 2 (SHP2) is an important regulatory factor in airway remodeling in asthma. This study aimed to explore the molecular mechanisms of SHP2 in neutrophils.
Glioblastoma (GBM) is one of the most malignant forms of cancer with the lowest survival ratio. Our study aims to utilize an integrated bioinformatic analysis to identify hub genes against GBM and explore the active phytochemicals with drug-like properties in treating GBM. The study employed databases of DisGenet, GeneCards, and Gene Expression Omnibus to retrieve GBM-associated genes, revealing 142 overlapping genes.
Institute of Clinical Microbiology, Immunology and Hygiene, University Hospital Erlangen and Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Germany; FAU Profile Center Immunomedicine (FAU I-MED), Germany. Electronic address:
Allergic bronchopulmonary aspergillosis is an incurable disease caused by the environmental mold Aspergillus fumigatus. This hypersensitivity pneumonia is characterized by an inflammatory type 2 immune response, accompanied by influx of eosinophils into the lung. To investigate the mode of action of eosinophils and the signaling events triggered by A.
Patients with chronic myeloid leukemia (CML) frequently develop resistance to tyrosine kinase inhibitors such as imatinib. In this study, we explored the role of the insulin-like growth factor 1 (IGF-1) signaling pathway in CML and imatinib resistance. An analysis of IGF-1 gene expression using public databases revealed elevated levels of insulin-like growth factor-binding proteins in patients with chronic-phase CML.
