Polyacetylenes from Saposhnikovia divaricata and their anticancer activity.

Nine polyacetylenes, including five new compounds named sadivaethynes E-I (1-5), were isolated from the roots of Saposhnikovia divaricata. Structural elucidation of compounds 1-5 was established by extensive spectroscopic analysis, quantum chemical calculations and DP4+ probability analysis. Among them, the absolute configuration of compound 1-2, 4-5 was unambiguous determined by ECD. Also, all compounds were evaluated for cytotoxicity against two human cancer cell lines (A549, HEPG2) in vitro, compound 9 showed moderate inhibitory effect with an IC50 value of 11.66 µM against HEPG2.

New chromones from the roots of Saposhnikovia divaricata (Turcz.) Schischk with anti-inflammatory activity.

Fifteen new chromones, sadivamones A-E (1-5), cimifugin monoacetate (6), sadivamones F-N (7-15), together with fifteen known chromones (16-30), were isolated from the ethyl acetate portions of 70% ethanol extract of Saposhnikovia divaricata (Turcz.) Schischk roots. The structures of the isolates were determined using 1D/2D NMR data and electron circular dichroism (ECD) calculations. Meanwhile, LPS induced RAW264.7 inflammatory cell model was used to determine the potential anti-inflammatory activity of all the isolated compounds in vitro. The results showed that compounds 2, 8, 12-13, 18, 20-22, 24, and 27 significantly inhibited the production of lipopolysaccharide (LPS)-induced NO in macrophages. To determine the signaling pathways involved in the suppression of NO production by compounds 8, 12 and 13, we investigated ERK and c-Jun N-terminal protein kinase (JNK) expression by western blot analysis. Further mechanistic studies demonstrated that compounds 12 and 13 inhibited the phosphorylation of ERK and the activation of ERK and JNK signaling in RAW264.7 cells via MAPK signaling pathways. Taken together, compounds 12 and 13 may be valuable candidates for the treatment of inflammatory diseases.

Pectic polysaccharides ameliorate the pathology of ulcerative colitis in mice by reducing pyroptosis.

Background: Ulcerative colitis (UC) is an inflammatory bowel disease which seriously affects the quality of life of patients. There has been an increasing amount of research related to the therapeutic effects and mechanisms of natural plant substances in the treatment of recurrent UC. Rauwolfia verticillata var. Hainanensis is a medicinal plant that is native to Hainan Island, China. Some studies have documented that pectic polysaccharides (PPs) from Rauvolfia inhibited the progression of colon ulcers. However, their mechanisms of action have not been established. Studies have revealed that suppressing pyroptosis can attenuate the damage of experimental colitis. However, it is unclear whether PPs from Rauvolfia verticillata inhibit inflammation through pyroptosis. This study investigated the effects and potential mechanisms of PPs extracted from Rauvolfia verticillata on experimental UC in mice. Methods: Male C57 mice (6-8 weeks old) were allocated into the control group, the dextran sulfate sodium (DSS)-induced UC model group (DSS group), or the DSS with pectic polysaccharides treatment group (DSS + PP group). The body weights, rectal bleeding, and stool consistencies in the mice were observed, and the disease activity index (DAI) score was calculated. Colon tissues were collected for pathological analysis by histological hematoxylin and eosin (H&E) staining. The levels of caspase-1 and interleukin (IL)-1ß were detected by immunohistochemistry. Pyroptosis was assessed by transmission electron microscopy. Results: UC in mice induced by DSS resulted in decreased general physical activity and body weight, increased DAI score, significant histological changes, inhibited caspase-1 and IL-1ß expression, and promoted pyroptosis. These DSS-induced changes could be partially ameliorated by administration of PP. Conclusions: PPs exerted an ameliorative effect on DSS-induced UC in mice by reducing pyroptosis.

Rauwolfia vomitoria Extract Represses Colorectal Cancer Cell Autophagy and Promotes Apoptosis.

BACKGROUND: Colorectal cancer (CRC) is one of the most frequent digestive tract tumors in the world with an increasing incidence. Currently, surgical resection and chemotherapy are the main therapeutic options; however, their effects are limited by various adverse reactions. Rauwolfia vomitoria extract (Rau) has been shown to repress the progression of multiple human cancers; however, whether Rau plays a role in CRC remains undetermined. METHODS: Influences of Rau treatment on HCT-116 and LoVo cells were estimated via MTT and colony formation experiments. Flow cytometry analysis was adopted to evaluate the apoptosis rate of HCT-116 and LoVo cells. Apoptosis-related proteins (Bcl-2, Bax, and caspase-3) and autophagy-related proteins (LC3 and P62) were assessed by Western blotting. Effects of Rau on autophagy of HCT-116 and LoVo cell were evaluated through GFP-LC3 analysis. In vivo xenograft tumor assay was conducted to further examine the role of Rau in CRC tumor growth. RESULTS: Rau remarkably repressed HCT-116 and LoVo cell viability and promoted HCT-116 and LoVo cell apoptosis in vitro in a dose-dependent manner. Rau increased the expression of caspase-3 and Bax and decreased the expression of Bcl-2 in HCT-116 and LoVo cells. Moreover, Rau was demonstrated to decrease the LC3||/LC3| ratio and increase the level of P62 in HCT-116 and LoVo cells. In addition, we found that Rau repressed xenograft tumor growth and also repressed autophagy in vivo. CONCLUSION: Our findings revealed that Rau repressed CRC cell viability and autophagy in vitro and in vivo, suggesting that Rau might be a potent therapeutic agent of CRC.

[Research on autophagy induced by two xanthone compounds in HepG2 cells].

To investigate the inhibitory effects of two xanthone compounds, 1-hydroxy-2,3,4,8-4 methoxy xanthone(here in after referred to as Fr15) and 1-hydroxy-2,3,4,6-4 methoxy xanthone(here in after referred to as Fr17), on the proliferation of hepatocellular carcinoma cells HepG2, and to further investigate their mechanism in combination with transcriptomics. Cell counting was used to detect the effects of two kinds of xanthone compounds Fr15 and Fr17(0, 0.03, 0.15, 0.3 mmoL·L~(-1)) on the proliferation of HepG2 cells; the effects of the two compounds Fr15 and Fr17 on HepG2 cell cycle were detected by flow cytometry; the changes of autophagosomes count in cells were observed under fluorescence microscope; the expression of autophagy marker proteins autophagy marker proteins SQSTM 1(p62) and microtubule associated protein 1 light chain 3 Ⅰ/Ⅱ(LC3 Ⅰ/Ⅱ) in the cells was detected by Western blot; the differentially expressed genes between the control group and the experimental group were analyzed by RNA-seq transcriptome sequencing; qRT-PCR was used to verify the differentially expressed genes in sequencing. The results showed that compounds Fr15 and Fr17 inhibited the proliferation of HepG2 cells with the increase of drug concentration and time. Flow cytometry showed that compounds Fr15 and Fr17 had little effect on HepG2 cell cycle. Fluorescence microscopy results showed that the number of autophagosomes in cells increased with the increase of drug concentration. Western blot showed that the expression of p62 protein was decreased and the expression of LC3-Ⅱ protein was significantly increased after drug addition. The results of RNA sequencing showed that 26 102 and 52 351 differentially expressed genes were obtained in Fr15 and Fr17 respectively. Analysis of KEGG showed that drug treatment had a great effect on autophagy pathway. qRT-PCR verified that 6 up-regulated genes were related to autophagy, and their trend was consis-tent with sequencing results, where all 6 genes showed an up-regulated trend. Two xanthone compounds Fr15 and Fr17 may inhibit proliferation of HepG2 cells by inducing autophagy.

Brazilian Green Propolis Extract Synergizes with Protoporphyrin IX-mediated Photodynamic Therapy via Enhancement of Intracellular Accumulation of Protoporphyrin IX and Attenuation of NF-κB and COX-2.

Brazilian green propolis (BGP) is noted for its impressive antitumor effects and has been used as a folk medicine in various cultures for many years. It has been demonstrated that BGP could enhance the cytotoxic effect of cytostatic drugs on tumor cells. Photodynamic therapy (PDT) is a therapeutic approach used against malignant cells. To assess the synergistic effect of BGP extract on protoporphyrin IX (PpIX)-mediated photocytotoxicity, MTT assays were performed using A431 and HeLa cells. TUNEL assay and Annexin V-FITC/PI staining were performed to confirm the induction of apoptosis. Western blotting analysis was performed to examine the pro-apoptotic proteins, anti-apoptotic proteins and inflammation related proteins in A431 cells. Intracellular accumulation of PpIX was examined by flow cytometry. The synergistic effect of BGP extract in PpIX-PDT was also evaluated with a xenograft model. Our findings reveal that BGP extract increased PpIX-mediated photocytotoxicity in A431 and HeLa cells. PpIX-PDT with BGP extract treatment resulted in a decrease in Bcl-xL and an increase in NOXA, Bax and caspase-3 cleavage. The protein expression levels of p-IKKα/ß, NF-κB and COX-2 were upregulated by PpIX-PDT but significantly attenuated when in combination with BGP extract. BGP extract was also found to significantly enhance the intracellular accumulation of PpIX in A431 cells. BGP extract increased PpIX-mediated photocytotoxicity in a xenograft model as well. Our findings provide evidence for a synergistic effect of BGP extract in PpIX-PDT both in vitro and in vivo.