Salvirrane A-F, six undescribed nordrimane sesquiterpene derivatives from Salvia castanea Diels f. tomentosa Stib and their cytotoxic activities.

Six undescribed nordrimane sesquiterpene derivatives, salvirrane A-F (1-6), were isolated from the roots and rhizomes of Salvia castanea Diels f. tomentosa Stib. Comprehensive spectral analysis and a quantum chemical calculation strategy were employed to determine their structures. These compounds represent four previously unreported nordrimane carbon skeletal types in Salvia genus, including 15-nor-drimane, 11,15-di-nor-drimane, 14,15-di-nor-drimane, and 11,14,15-tri-nor-drimane sesquiterpenes. All compounds were evaluated for their cytotoxic activities against several human cancer cell lines (A549, H460, Hep3B, MCF7, PC3, and HeLa). The results showed that 3 exhibited low activity against MCF7 cells (IC50,72.72 ± 6.95 µM) and moderate activity against HeLa cells (IC50, 9.80 ± 0.64 µM). Moreover, the EdU (5-ethynyl-2'-deoxyuridine) assay demonstrates that 3 displays dose-dependent efficacy in suppressing the proliferation of HeLa cells. Network pharmacology and molecular docking technology implied that 3 may potentially bind to Src (proto-oncogene tyrosine-protein kinase) to exert anti-proliferative activity.

(±)-Salvicatone A: A Pair of C27-Meroterpenoid Enantiomers with Skeletons from the Roots and Rhizomes of Salvia castanea Diels f. tomentosa Stib.

(±)-Salvicatone A (1), a C27-meroterpenoid featuring a unique 6/6/6/6/6-pentacyclic carbon skeleton with a 7,8,8a,9,10,10a-hexahydropyren-1 (6H)-one motif, was isolated from the roots and rhizomes of Salvia castanea Diels f. tomentosa Stib. Its structure was characterized by comprehensive spectroscopic analyses along with computer-assisted structure elucidation, including ACD/structure elucidator and quantum chemical calculations with 1H/13C NMR and electronic circular dichroism. Biogenetically, compound 1 was constructed from decarboxylation following [4 + 2] Diels-Alder cycloaddition reaction between caffeic acid and miltirone analogue. Bioassays showed that (-)-1 and (+)-1 inhibited nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophage cells with an IC50 value of 6.48 ± 1.25 and 15.76 ± 5.55 µM, respectively. The structure-based virtual screening based on the pharmacophores in ePharmaLib, as well as the molecular docking and molecular dynamics simulations study, implied that (-)-1 and (+)-1 may potentially bind to retinoic acid receptor-related orphan receptor C to exert anti-inflammatory activities.

Wunorlactones A-G, seven undescribed 7/8/5 and 7/8/3 carbon skeleton schinortriterpenoids from the stems and leaves of Schisandra chinensis, and their neuroprotective activities.

Schisandra chinensis is an important traditional Chinese medicine and its main bioactive components are lignans and schinortriterpenoids (SNTs). The aim of this study was to explore the biologically rich SNTs from the stem and leaves of S. chinensis (SCSL). Here, seven previously undescribed 7/8/5 and 7/8/3 carbon skeleton SNTs (1-7) were reported. Their structures were determined by NMR, UV, MS, ECD, and X-ray diffraction analyses, and the neuroprotective activities of these compounds on corticosterone-induced PC12 cell injury were evaluated. The results showed that 1, 5, and 7 (25 µM) had neuroprotective effects, and the cell viability was increased by 20.07%, 14.24%, and 15.14% (positive control: 30.64%), respectively. These findings increased the number of described SNTs in SCSL, and the neuroprotective activities of all compounds indicated their potential application in neurodegenerative diseases.

Diterpenoids from Sigesbeckia glabrescens with anti-inflammatory and AChE inhibitory activities.

Fourteen previously undescribed diterpenoids, including seven ent-pimarane-type diterpenoids and seven phytane-type diterpenes, together with five known ones, were isolated from the aerial parts of Sigesbeckia glabrescens. The structures and absolute configurations of undescribed compounds were elucidated based on extensive spectroscopic techniques, ECD calculations, Mo2(OAC)4-induced ECD, Rh2(OCOCF3)4-induced ECD, calculated 13C NMR, and chemical methods. In the anti-inflammatory bioassay, siegetalis H showed potent inhibitory effect on LPS-induced NO production in RAW264.7 murine macrophages with an IC50 value at 17.29 µM. Furthermore, siegetalis H suppressed the protein expression of iNOS and COX-2 in LPS-stimulated RAW264.7 cells. Mechanistically, siegetalis H suppressed the phosphorylation and degradation of IκBα, as well as the activation of the NF-κB signaling pathway. In addition, the AChE inhibition assay displayed that 3-O-acetyldarutigenol had a remarkable inhibitory effect against AChE with an IC50 value at 7.02 µM. Kinetic study on 3-O-acetyldarutigenol indicated that it acted as a mixed-type inhibitor, and the binding mode was explored by molecular docking.

Rare benzonaphthoxanthenones from Chinese folk herbal medicine Polytrichum commune and their anti-neuroinflammatory activities in vitro.

Two new (1-2) as well as five known (3-7) compounds were isolated from Polytrichum commune, a folk herbal medicine in China, and three of them (2, 4, 5) belong to benzonaphthoxanthenones that are rarely found in nature. Their structures were elucidated by the approach to 1D and 2D NMR spectra. The absolute configuration of 2 was assigned by comparing its experimental and calculated ECD data. 1-5 were investigated for their anti-neuroinflammatory activity against LPS-induced BV-2 cells. 1 and 3 exhibited well protective effect at a concentration of 2.5 µmol/mL. Molecular docking studies were adopted to further investigate the possible mechanism, whose results suggested that 1 might exert anti-neuroinflammatory effect by inhibiting activity of p38α, JNK2 and TAK1 to reduce the liberation of pro-inflammatory cytokines.

Systems Pharmacological Approach to Investigate the Mechanism of Ohwia caudata for Application to Alzheimer's Disease.

Ohwia caudata (OC)-a traditional Chinese medicine (TCM)-has been reported to have large numbers of flavonoids, alkaloids, and triterpenoids. The previous studies on OC for treating Alzheimer's disease (AD) only focused on single targets and its mechanisms, while no report had shown about the synergistic mechanism of the constituents from OC related to their potential treatment on dementia in any database. This study aimed to predict the bioactive targets constituents and find potential compounds from OC with better oral bioavailability and blood-brain barrier permeability against AD, by using a system network level-based in silico approach. The results revealed that two new flavonoids, and another 26 compounds isolated from OC in our lab, were highly connected to AD-related signaling pathways and biological processes, which were confirmed by compound-target network, Gene Ontology (GO) analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, respectively. Predicted by the virtual screening and various network pharmacology methods, we found the multiple mechanisms of OC, which are effective for alleviating AD symptoms through multiple targets in a synergetic way.