6-O-angeloylplenolin inhibits osteoclastogenesis in vitro via suppressing c-Src/NF-κB/NFATc1 pathways and ameliorates bone resorption in collagen-induced arthritis mouse model.

One of the effective therapeutic strategies to treat rheumatoid arthritis (RA)-related bone resorption is to target excessive activation of osteoclasts. We discovered that 6-O-angeloylplenolin (6-OAP), a pseudoguaianolide from Euphorbia thymifolia Linn widely used for the treatment of RA in traditional Chinese medicine, could inhibit RANKL-induced osteoclastogenesis and bone resorption in both RAW264.7 cells and BMMs from 1 µM and protect a collagen-induced arthritis (CIA) mouse model from bone destruction in vivo. The severity of arthritis and bone erosion observed in paw joints and the femurs of the CIA model were attenuated by 6-OAP administered at both dosages (1 or 5 mg/kg, i.g.). BMD, Tb.N and BV/TV were also improved by 6-OAP treatment. Histological analysis and TRAP staining of femurs further confirmed the protective effects of 6-OAP on bone erosion, which is mainly due to reduced osteoclasts. Molecular docking indicated that c-Src might be a target of 6-OAP and phosphorylation of c-Src was suppressed by 6-OAP treatment. CETSA and SPR assay further confirmed the potential interaction between 6-OAP and c-Src. Three signaling molecules downstream of c-Src that are vital to the differentiation and function of osteoclasts, NF-κB, c-Fos and NFATc1, were also suppressed by 6-OAP in vitro. In summary, the results demonstrated that the function of c-Src was disrupted by 6-OAP, which led to the suppression of downstream signaling vital to osteoclast differentiation and function. In conclusion, 6-OAP has the potential to be further developed for the treatment of RA-related bone erosion.

Controlling non small cell lung cancer progression by blocking focal adhesion kinase-c-Src active site with Rosmarinus officinalis L. phytocomponents: An in silico and in vitro study.

Background: Non small cell lung cancer (NSCLC) is a global, fatal oncological malady to which conventional and targeted therapies proved less effective with consequent side effects; hence, phytocomponents from herbal sources may provide potent alternative and should be tested for cancer intervention. Activation and overexpression of proto-oncogene tyrosine kinase Src (c-Src) and focal adhesion kinase (FAK) lead to cell proliferation and invasion. Hence, in the present investigation, in silico analysis was carried out to identify molecular intervention of phytocomponents in blocking the active site and thus inhibiting c-Src and FAK activation, which in turn could control progression of NSCLC. Materials and Methods: In silico analysis was carried out using Molegro Virtual Docker, Molegro Molecular Viewer, and ClusPro server for ligand-protein and protein-protein interaction study. Phytochemical analysis and assay for antioxidant activity of hydroalcoholic extract of Rosmarinus officinalis L. were carried out using standard phytochemical tests, high-performance thin-layer chromatography, and 2, 2-diphenyl-1-picrylhydrazyl assay. Effectiveness of extract in arresting cell proliferation was confirmed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay on A549 cell line. Results: In silico analysis indicated effective binding of rosmarinic acid to the active site of target proteins FAK and c-Src, blocking their activity. MTT assay revealed potent antiproliferative activity of hydroalcoholic extract which acted in dose-dependent manner. Phytochemical analysis confirmed that the extract was rich in phytocomponents and had antioxidant activity of 94.9%, which could therefore effectively eliminate free radicals and inhibit cell progression. Conclusion: In silico and in vitro studies confirmed that phytocomponents present in hydroalcoholic extract of R. officinalis L. could effectively block the active site of target proteins and thus controlled cell proliferation on NSCLC cells, suggesting herb as an effective alternative medicine for the treatment of NSCLC.

Anti-osteoporosis effect of Semen Cuscutae in ovariectomized mice through inhibition of bone resorption by osteoclasts.

ETHNOPHARMACOLOGICAL RELEVANCE: Semen Cuscutae, called Tu-si-zi in Chinese, is a kind of dried mature seed in the Convolvulaceae family. It mainly distributes in China, Korea, Pakistan, Vietnam, India and Thailand. It is used as a kidney-tonifying drug for treatment of aging related diseases such as osteoporosis in traditional Chinese medicine. However, the exact mechanisms on bone resorption are poorly studied. AIM OF THE STUDY: The aim of this study was to investigate the potential effect of Semen Cuscutae on ovariectomy (OVX)-induced osteoporosis in mice and clarify the exact mechanisms by which Semen Cuscutae exert the anti-osteoporosis effect. MATERIALS AND METHODS: Qualitative and quantitative analyses of Semen Cuscutae were performed by UPLC-Q-TOF-MS and HPLC-MS/MS, respectively. Changes in bone mineral density (BMD) induced by OVX in mice were measured by dual-energy X-ray absorptiometry and micro-computed tomography (µCT). Tartrate-resistant acid phosphatase (TRAP) staining as well as hematoxylin and eosin (HE) staining were used to observe bone microarchitectural changes. ELISA kits were used to assess the therapeutic effects of Semen Cuscutae on the serum levels of osteoprotegerin (OPG), tartrate-resistant acid phosphatase 5b (TRACP-5b), and receptor activator of nuclear factor-κB (RANKL). The effect of Semen Cuscutae on primary cell viability was assessed using CCK-8 and anti-tartrate phosphatase assays. TRAP staining and actin ring staining were used to observe the effect of Semen Cuscutae on osteoclast differentiation. Western blotting was used to measure the effects of Semen Cuscutae on expressions of NFATC1, c-Src kinase, and c-fos. RESULTS: Results from UPLC-Q-TOF-MS showed that the main components of Semen Cuscutae were flavonoid compounds that included quercitrin, quercetin, hyperoside, caffeic acid, rutin, chlorogenic acid, luteolin, apigenin, kaempferol, isoquercetin, cryptochlorogenic acid, isorhamnetin-3-O-glucoside, and astragalin. After the Semen Cuscutae extract was orally administered to OVX mice, bone density increased (P < 0.01) and bone microstructure was significantly improved (P < 0.01 or 0.05). Additionally, Semen Cuscutae exhibited a significant descending effect in the levels of serum TRACP-5b and RANKL, while there was a significant increase in OPG in the Semen Cuscutae group compared with the OVX group, especially at high doses. Moreover, we found that increasing of c-fos, c-Src kinase, and NFATC1 protein expressions were reversed by Semen Cuscutae in vitro and in vivo. CONCLUSIONS: Our results showed that Semen Cuscutae exhibited anti-osteoporosis effects through the c-fos/c-Src kinase/NFATC1 signaling pathway.