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Herein we report the anti-inflammatory activity of lobaric acid and pseudodepsidones isolated from the nordic lichen Stereocaulon paschale. Lobaric acid (1) and three compounds (2, 7 and 9) were found to inhibit the NF-κB activation and the secretion of pro-inflammatory cytokines (IL-1β and TNF-α) in LPS-stimulated macrophages. Inhibition and docking simulation experiments provided evidence that lobaric acid and pseudodepsidones bind to PPAR-γ between helix H3 and the beta sheet, similarly to partial PPAR-γ agonists. These findings suggest that lobaric acid and pseudodepsidones reduce the expression of pro-inflammatory cytokines by blocking the NF-κB pathway via the activation of PPAR-γ., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Four new compounds, paucinervins A-D (1-4), and 15 known ones were isolated from the leaves of Garcinia paucinervis. The structures of the new compounds were elucidated by spectroscopic evidences. All of the 19 compounds were evaluated for their apoptosis-inducing effects using HeLa-C3 cells which have been genetically engineered to possess a fluorescent biosensor capable of detecting caspase-3 activation. Eight of them were found to activate caspase-3 in HeLa-C3 cells within 72 h at the concentration of 25 microM. Moreover, the values of IC50 were measured for all four new compounds on HeLa cells using the MTT assay. Among them, compound 2 (paucinervin B) had the lowest IC50 value of 9.5 microM, while the other three new compounds had much higher IC50 values of 29.5, 52.5, and 95.6 microM, respectively. This result shows that paucinervin B has the strongest inhibitory effect against HeLa cell growth among these four newly identified paucinervins and it may have the potential to be developed into a new anticancer candidate., (Copyright (c) 2010. Published by Elsevier Ltd.)

Salicyl acyl glucuronide (SAG) is a significant metabolite of salicylic acid (SA) and aspirin. We have shown that, under physiological conditions in vitro, SAG undergoes rearrangement in a manner consistent with acyl migration to its 2-, 3- and 4-O-acyl positional isomers as the predominant pathway (T1/2 values were 1.4-1.7 hr in buffer at pH 7.4 and 37 degrees). Incubation of SAG or a mixture of its rearrangement isomers (iso-SAG) (each at approximately 50 micrograms SA equivalents/mL) with human serum albumin (HSA, at approximately 40 mg/mL) revealed the formation of covalent adducts with the protein, with peak concentrations of 1-2 micrograms SA equivalents/mL. The data support a role for the rearrangement/glycation mechanism of adduct formation. Covalent adducts of SA were also detected in the plasma of humans taking aspirin (at > or = 1200 mg/day), but the concentrations were low (<< 100 ng SA equivalents/mL). Reactivity of SAG thus provides a mechanism (though of uncertain quantitative importance) of covalent attachment of the salicyl moiety of aspirin to tissue macromolecules, which is in addition to its well-known acetylating capacity.