Osthole Activates the Cholinergic Anti-Inflammatory Pathway via α7nAChR Upregulation to Alleviate Inflammatory Responses.

Osthole (also known as Osthol) is the main anti-inflammatory coumarin found in Cnidium monnieri and severs as the exclusive quality-controlled component according the Chinese Pharmacopoeia. However, its underlying anti-inflammatory mechanism remains unknown. In this study, we demonstrated that Osthole treatment significantly inhibited the generation of TNF-α, but not IL-6 in the classical LPS-stimulated RAW264.7 macrophage model. In addition, LPS induced the activation of both MAPK and NF-κB signalling pathways, of which the former was dose-dependently restrained by Osthole via suppressing the phosphorylation of JNK and P38 proteins, while the phosphorylation of IκB and P65 proteins remained unaffected. Interestingly, Osthole dose-dependently up-regulated the expression of the key cholinergic anti-inflammatory pathway regulator α7nAChR, and the TNF-α inhibition effect of Osthole was also significantly alleviated by the treatment of α7nAChR antagonist methylbetaine. These results demonstrate that Osthole may regulate TNF-α by promoting the expression of α7nAChR, thereby activate the vagus nerve-dependent cholinergic anti-inflammatory pathway.

A phylogenetic and morphological study of the Tectariafuscipes group (Tectariaceae), with description of a new species.

The fern species Tectariafuscipes and morphologically similar species, which are common in tropical and subtropical mainland Asia, constitute a taxonomically confusing group. To better understand species boundaries and relationships within the T.fuscipes group, we conducted phylogenetic analyses of five plastid regions and morphological observations of herbarium specimens and living plants. As a result, we produced a generally well-resolved phylogeny of the T.fuscipes group and related species in Asia. The phylogenetic analyses supported the monophyly of the T.fuscipes group, which includes T.dissecta, T.fuscipes, T.ingens, T.paradoxa, T.setulosa, T.subfuscipes, T.subsageniacea and a new species, but excludes T.kusukusensis. However, T.fuscipes, T.subfuscipes and T.subsageniacea are almost indistinguishable in morphology, which form a complex characterised by the black linear-lanceolate stipe scales. The new species found in southern China and Vietnam is described here as T.fungii. It is similar to the T.fuscipes complex and T.kusukusensis, but differs from the former mainly by its brown-castaneous lanceolate stipe scales and from the latter by having nearly hairless laminae (versus frond axes abaxially bearing copious hairs).