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Abstract (+)-usnic acid (UA) is an active natural phenolic acid ingredient originating from Chinese traditional Tibetan herb. Usnea acid is expected to become a new agent for anticancer and remarkable antitumor. To reveal its metabolic profile, metabolites identification of UA in vivo was studied using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) in this present study. The chromatographic separation was performed on a C 18 column with a mobile phase consisted of methanol and water with a flow rate of 0.4 ml/min. The mass spectral analysis conducted in a negative electrospray ionization mode combined with information-dependent acquirement technology (IDA) was used to trace all the potential UA metabolites. Several sensitive and specific multiple data-mining techniques especially key product ions (KPIs) filter were applied to hunt and identify metabolites rapidly. As a result, a total of 36 metabolites were detected after oral administration of UA, including 33, 8 and 16 in rat urine, plasma and bile, respectively. These results showed that the probable metabolite pathways of UA were oxidation, reduction, dihydroxylation, glycine conjugation, glucuronide conjugation, N -acetylcysteine conjugation and methylation. It is the first time to elucidate the profile of UA in vivo. These results not only provided the basis of UA pharmacological properties, but also gave the guidance in clinical medication. Moreover, the analysis strategy and methodology proposed in this paper could be widely used in characterization of other phenolic acids metabolites. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract: Arctiin, an important lignan compound in Fructus Arctii, has been reported to possess various kinds of bioactivities. Previous studies on the pharmacokinetic of arctiin after oral administration showed that it had a rapid absorption phase followed by a sharp but lasting disappearance. To gain deep insight into the action mechanism of arctiin, the excretion and metabolism of arctiin in vivo should be further studied. In this paper, three metabolites were isolated and identified in rat feces as (−)-enterolactone (M-1), (−)-arctigenin (M-2) and [(2R,3R)-2-(3′-hydroxybenzyl)-3-(3″,4″-dimethoxybenzyl)-butyrolactone] (M-3). Based on the structures of three metabolites, possible metabolic pathways of arctiin in rats are proposed. At the same time, the cumulative excretion rate of arctiin and its metabolites in rat urine and feces were determined, indicating that arctiin was excreted 19.84% in urine and 1.80% in feces, respectively, enterolactone, the most main metabolite, was excreted 35.80% in feces. These results provide very important information for understanding the metabolism and excretion of arctiin in vivo and speculating its action mechanism, they can provide useful information and reference for further metabolic investigations on arctiin in humans. [Copyright &y& Elsevier]

Abstract: Phlomis umbrosa Turcz has been used as the traditional medicine for thousands of years in China. In this paper, the acetic acid-induced writhing test, the hot plate test, the carrageenan-induced paw edema test, the xylene-induced ear swelling test, and the acetic acid-induced Evans blue leakage and leukocyte infiltration test were used to investigate the antinociceptive and anti-inflammatory activities of the aqueous extract of this plant (25, 50 and 100mg/kg i.p.). Good dose-dependent effects were obtained in most of these tests, except in the hot plate test and the acetic acid-induced Evans blue leakage test. TLC and HPLC analyses showed iridoid glucosides were the main compositions of this extract. These findings suggested that the aqueous extract of P. umbrosa has significant antinociceptive and anti-inflammatory activities. [Copyright &y& Elsevier]