Dendrocandin U from Dendrobium officinale Kimura et Migo Inhibits M1 Polarization in Alveolar Macrophage by Suppressing NF-κB Signaling Pathway.

Dendrobium officinale Kimura et Migo is a valuable and homologous medicine and food traditional Chinese medicine. Currently there are few studies on the anti-inflammatory activity of lipophilic components. The aim of this study was to explore the anti-inflammatory effect and mechanism of the lipophilic compounds in Dendrobium officinale. Six compounds were isolated and identified, including three bibenzyl compounds, dendrocandin U, dendronbibisline B, erianin, and three lignans, (-)-syringaresinol, (+)-syringaresinol-O-ß-D-glucopyranoside, 5-methoxy-(+)-isolariciresinol. Among them, dendronbibisline B and 5-methoxy-(+)-isolariciresinol were isolated from Dendrobium officinale for the first time. Besides, we found dendrocandin U, dendronbibisline B and (-)-syringaresinol exhibited the anti-inflammation to inhibit nitric oxide secretion induced by lipopolysaccharide (LPS)/interferon (IFN-γ) in MH-S cells. Furthermore, dendrocandin U could inhibit the expression of tumor necrosis factor-α (TNF-α), Cluster of Differentiation 86 (CD86), and reduce inflammatory morphological changes of macrophages. Meanwhile, we confirmed that the anti-inflammation mechanism of dendrocandin U was to inhibit M1 polarization by suppressing toll-like receptor 4 (TLR4)/recombinant myeloid differentiation factor 88 (MyD88)/nuclear factor kappa B (NF-κB) signaling pathway. In this paper, dendrocandin U with significant anti-inflammatory activity was found from Dendrobium officinale, which could provide a basis for the study of its anti-inflammatory drugs.

Plasma pharmacokinetics and tissue distribution of bufotalin in mice following single-bolus injection and constant-rate infusion of bufotalin solution.

Bufotalin is one of the active antitumor components in Ch'an Su which is a widely used traditional Chinese medicine. However, there is insufficient information on the biopharmaceutical properties of bufotalin based on pharmacokinetic studies. To investigate the pharmacokinetics and tissue distribution of bufotalin, single-bolus injection and constant-rate infusion of bufotalin solution were performed in mice. After single intravenous administration, bufotalin was quickly distributed and eliminated from the plasma with a t1/2 of 28.6 min and an MRT of 14.7 min. Bufotalin concentrations in brain and lung were significantly higher than those in blood and other tissues at 30 min after dosing. The steady-state bufotalin plasma concentration and tissue distribution were determined using a novel constant-rate infusion device, and the distribution characteristics were similar to those of single-bolus injection. These results indicated that bufotalin could cross the blood-brain barrier and naturally target the lung. Bufotalin might be a promising antitumor candidate for lung cancer.