Polyketides with anti-inflammatory activity isolated from Rhodiola tibetica endophytic fungus Penicillium sp. HJT-A-10.

Seven undescribed polyketide compounds (1-4, 9-11) and six known polyketide compounds (5-8,12, 13) were isolated from Rhodiola tibetica endophytic Penicillium sp. HJT-A-10. The structural of seven undescribed polyketides metabolites were established on the basis of spectroscopic methods. The results of anti-inflammatory activity showed that compounds 1-8，10-13 had significant inhibitory effects on LPS-induced NO production in RAW 264.7 cells.

Phytochemical, Chemotaxonomic and Bioinformatics Study on Laportea bulbifera (Urticaceae).

Phytochemical investigation of the aerial part of Laportea bulbifera (Siebold & Zucc.) Wedd. (L. bulbifera) showed the isolation of seventeen compounds, including five flavonoids (1-4 and 6), one terpenoid (5), five phenolic acids (7-11), one coumarin (12), two steroids (13-14), and three alkaloids (15-17). Structure elucidations of these compounds were performed on the basis of extensive NMR experiments and compared with the published data in the references. It is remarkable that compounds (3-5) were firstly isolated from the Urticaceae family, compounds (3-8, 11 and 15-17) were firstly obtained from genus Laportea. Furthermore, the result of the chemotaxonomic significance discussion showed that compounds (2-4) may can be served as compound fingerprints to distinguish between species of L. bulbifera and genus Urtica, and what' more, we proposed a bold conjecture that isoflavones can distinguish between species of L. bulbifera and genus Urtica. At the same time, the molecular docking method was used to evaluate the inhibitory effect of these compounds on human steroid 5α-reductase 2 (SRD5α2). The results showed that compounds (1-4 and 6) had better expected effects than the positive drug finasteride can by effectively binding to the active sites of SRD5α2. This study assisted in the future phytochemical and chemotaxonomic research on genus Laportea. Simultaneously, this research provided the theoretical evidence for the application of L. bulbifera in treating benign prostatic hyperplasia (BPH).

Noncanonical mono(ADP-ribosyl)ation of zinc finger SZF proteins counteracts ubiquitination for protein homeostasis in plant immunity.

Protein ADP-ribosylation is a reversible post-translational modification that transfers ADP-ribose from NAD+ onto acceptor proteins. Poly(ADP-ribosyl)ation (PARylation), catalyzed by poly(ADP-ribose) polymerases (PARPs) and poly(ADP-ribose) glycohydrolases (PARGs), which remove the modification, regulates diverse cellular processes. However, the chemistry and physiological functions of mono(ADP-ribosyl)ation (MARylation) remain elusive. Here, we report that Arabidopsis zinc finger proteins SZF1 and SZF2, key regulators of immune gene expression, are MARylated by the noncanonical ADP-ribosyltransferase SRO2. Immune elicitation promotes MARylation of SZF1/SZF2 via dissociation from PARG1, which has an unconventional activity in hydrolyzing both poly(ADP-ribose) and mono(ADP-ribose) from acceptor proteins. MARylation antagonizes polyubiquitination of SZF1 mediated by the SH3 domain-containing proteins SH3P1/SH3P2, thereby stabilizing SZF1 proteins. Our study uncovers a noncanonical ADP-ribosyltransferase mediating MARylation of immune regulators and underpins the molecular mechanism of maintaining protein homeostasis by the counter-regulation of ADP-ribosylation and polyubiquitination to ensure proper immune responses.

[Preliminary study of dihydroartemisin in inhibiting invasion and metastasis of hepatoma cells].

It is reported that dihydroartemisinin could reduce the expression of phosphorylated adhesion kinase and matrix metalloproteinase-2, inhibit the growth, migration and invasion of ovarian cancer cells, promote the formation of Treg cells through TGF-beta/Smad signaling pathway, and play an immunosuppressive role; dihydroartemisinin could also inhibit the growth of lung cancer cells by inhibiting the expression of vascular endothelial growth factor(VEGF) receptor KDR. However, there are few studies on dihydroartemisinin in hepatocellular carcinoma cells. In order to preliminarily explore the effect of dihydroartemisinin on invasion and metastasis of hepatocellular carcinoma cells, CCK-8 method and crystal violet staining were used to detect the effect of dihydroartemisinin on the growth of hepatocellular carcinoma cell 7402 and highly metastatic hepatocellular carcinoma cell MHCC97 H. The effects of dihydroartemisinin on the invasion and metastasis of hepatocellular carcinoma cell 7402 and highly metastatic hepatocellular carcinoma cell MHCC97 H were studied by using cell wound healing and Transwell. Western blot was used to detect the protein expression of epidermal growth factor receptor(EGFR) and its downstream signaling pathway in cells treated with dihydroartemisinin for 48 hours. The results showed that dihydroartemisinin could inhibit the growth of hepatocellular carcinoma cell 7402 and highly metastatic hepatocellular carcinoma cell MHCC97 H at 25 µmol·L~(-1). As compared with the control group, the number of cell clones was significantly reduced, and the ability of cell migration and invasion was weakened. Western blot results showed that as compared with the control group, dihydroartemisinin group could down-regulate the protein expression of EGFR and its downstream signaling pathways p-AKT, p-ERK, N-cadherin, Snail and Slug, and up-regulate the expression of E-cadherin protein, thus affecting the migration, invasion and metastasis of hepatocellular carcinoma cells 7402 and MHCC97 H.

Triterpenoids from Euphorbia maculata and Their Anti-Inflammatory Effects.

Euphorbia maculata is a medicinal plant of the Euphorbiaceae family, which can produce anti-inflammatory and cancer chemopreventive agents of triterpenoids. The present study reports on the bioactive triterpenoids of this plant. Two new lanostane-type triterpenoids, named (3S,4S,7S,9R)-4-methyl-3,7-dihydroxy-7(8→9) abeo-lanost-24(28)-en-8-one (1) and 24-hydroperoxylanost-7,25-dien-3ß-ol (2), together with 15 known triterpene derivatives, were isolated from Euphorbia maculata. The structures of the new compounds were determined on the basis of extensive spectroscopic data (UV, MS, ¹H and 13C-NMR, and 2D NMR) analysis. All tetracyclic triterpenoids (1⁻11) were evaluated for their anti-inflammatory effects in the test of TPA-induced inflammation (1 µg/ear) in mice. The triterpenes exhibited significant anti-inflammatory activities.

Ethyl acetate extract of Peperomia tetraphylla induces cytotoxicity, cell cycle arrest, and apoptosis in lymphoma U937 cells.

The current study evaluated the cytotoxicity and the mechanism of apoptotic induction by Peperomia tetraphylla in U937 lymphoma cells. The results showed that P. tetraphylla ethyl acetate extract (EAEPT) inhibited the cell growth in U937 cells by MTT assay. After the U937 cells were treated with EAEPT, the cells exhibited marked morphological features of apoptosis (Hoechst 33342 staining) and the number of apoptotic cell (Annexin V-FITC/PI staining) increased. The treatment of EAEPT could induce loss of mitochondrial membrane potential (MMP) and increase the ROS level. Moreover, EAEPT treatment resulted in the accumulation of cells at S phase. We found that EAEPT could induce the cleavage of the caspase 3, caspase 8, caspase 9 and Bid. And the treatment of EAEPT could increase expression of Bax and down-regulate the expression of CCNB1, CCND1 and CDK1. The sub-fraction of EAEPT, namely EASub1 demonstrated the highest cytotoxicity activity on U937 cells. It was confirmed that EAEPT could inhibit the growth of U937 cells by blocking the cell cycle and prompted apoptosis via the ROS-medicated mitochondria pathway in vitro.

C21 steroidal glycosides from the roots of Cynanchum paniculatum.

As a part of our continuing research for bioactive constituents from Cynanchum plants, four new C21 steroidal glycosides, cynapanoside D-G (1-4), together with six known compounds (5-10) were isolated from the roots of Cynanchum paniculatum (Bge.) Kitag. Their structures were elucidated on the basis of 1D- and 2D-NMR spectroscopic data as well as HR-ESI-MS analysis. Compound 8 exhibited potent inhibitory activities against HL-60, HT-29, PC-3 and MCF-7 cell lines with IC50 values of 8.3, 7.5, 34.3 and 19.4µM, respectively and compounds 1-4 and 9 displayed moderate cytotoxicity against the four cell lines. The in vitro antioxidant activities of compounds 1-4, 8 and 9 were assayed by DPPH radical scavenging activity. Antibacterial and antifungal activities of compounds 1-4, 8 and 9 were also tested.

Isolation and identification of two new compounds from marine-derived fungus Acremonium fusidioides RZ01.

Two new compounds, (22E)-25-carboxy-8ß,14ß-epoxy-4α,5α-dihydroxyergosta-2,22-dien-7-one (1) and fusidione (3), along with two known compounds, 5α,8α-epidioxy ergosta-6,22-diene-3ß-ol (2) and microperfuranone (4), were isolated from the fermentation products of the marine-sourced fungus Acremonium fusidioides RZ01. The structures of compounds 1 and 3 were elucidated by extensive spectroscopic methods, especially 2D NMR, and their absolute configurations were suggested on the basis of the circular dichroism spectral analysis and the NOESY data. Both new compounds showed inhibitory activity against HL-60 cells with IC50 values being16.6 and 44.9 µmol·L-1, respectively.

Regulation of the Arabidopsis anther transcriptome by DYT1 for pollen development.

Several genes encoding transcription factors have been shown to be essential for male fertility in plants, suggesting that transcriptional regulation is a major mechanism controlling anther development in Arabidopsis. DYSFUNCTIONAL TAPETUM 1 (DYT1), a putative bHLH transcription factor, plays a critical role in regulating tapetum function and pollen development. Here, we compare the transcriptomes of young anthers of wild-type and the dyt1 mutant, demonstrating that DYT1 is upstream of at least 22 genes encoding transcription factors and regulates the expression of a large number of genes, including genes involved in specific metabolic pathways. We also show that DYT1 can bind to DNA in a sequence-specific manner in vitro, and induction of DYT1 activity in vivo activated the expression of the downstream transcription factor genes MYB35 and MS1. We generated DYT1-SRDX transgenic plants whose fertility was dramatically reduced, implying that DYT1 probably acts as a transcriptional activator. Furthermore, we used yeast two-hybrid assays to show that DYT1 forms homodimers and heterodimers with other bHLH transcription factors. Our results demonstrate the important role of DYT1 in regulating anther transcriptome and function, and supporting normal pollen development.

A new acylated flavonoid glycoside from the flowers of Camellia nitidissima and its effect on the induction of apoptosis in human lymphoma U937 cells.

From the EtOH extract of the flowers of Camellia nitidissima Chi, a new acylated flavonoid glycoside, quercetin 7-O-(6"-O-E-caffeoyl)-ß-D-glucopyranoside (1), has been isolated, together with three known flavonoids: quercetin (2), quercetin 3-O-ß-D-glucopyranoside (3), and quercetin 7-O-ß-D-glucopyranoside (4). Their structures were elucidated on the basis of spectroscopic analysis. Compound 1 was shown to inhibit proliferation and to induce apoptosis of human lymphoma U937 cells.

Three new secolignan glycosides from Urtica fissa E. Pritz.

Three new secolignan glycosides {3,4-trans-4-[bis(3,4-dimethoxyphenyl)methyl]-2-oxotetrahydrafuran-3-yl}methyl-O-ß-glucopyranoside (1), {3,4-trans-4-[(3-methoxy-4-hydroxyphenyl)(3,4-dimethoxyphenyl)methyl]-2-oxotetrahydrafuran-3-yl}methyl-O-ß-glucopyranoside (2) and {3,4-cis-4-[(3-methoxy-4-hydroxyphenyl)(3,4-dimethoxyphenyl)methyl]-2-oxotetrahydrafuran-3-yl}methyl-O-ß-glucopyranoside (3) were isolated from the roots of Urtica fissa E. Pritz. Their structures were identified by spectral methods including 1D NMR, 2D NMR and HR-EI-MS.

New bibenzyl glycosides from leaves of Camellia oleifera Abel. with cytotoxic activities.

Studies on the chemical constituents of leaves of Camellia oleifera Abel. led to the isolation of 3 new bibenzyl glycosides. Their structures have been elucidated as 1-(3',5'-dihydroxy)phenyl-2-(4″-O-ß-D-glucopyranosyl)phenylethane (1), 1-(3',5'-dimethoxy)phenyl-2-(4″-O-ß-D-glucopyranosyl)phenylethane (2) and 1-(3',5'-dimethoxy)phenyl-2-[4″-O-ß-D-glucopyranosyl(6→1)-O-α-L-rhamnopyranosyl]phenylethane (3) through spectral studies including HR-ESI-MS, ((1))H NMR, ((13))C NMR and 2D NMR experiments. All the above 3 bibenzyl glycosides showed cytotoxic activities to Hela and hep2 cell lines.

Two diketopiperazines from Acanthopanax senticosus Harms.

From the dried aerial parts of Acanthopanax senticosus, two new diketopiperazines, eleutherazines A (1) and B (2), were isolated. Their structures were elucidated on the basis of chemical and spectroscopic methods.

Two new secolignan glycosides from the roots of Urtica triangularis Hand.-Mazz.

Two secolignan glycoside isomers, urticaside A (1) and urticaside B (2), were isolated from the roots of Urtica triangularis Hand.-Mazz. Their structures were elucidated by means of spectral analyses including 1D, 2D NMR and HR-EI-MS.

Lignan and flavonoid glycosides from Urtica laetevirens Maxim.

A new compound named pinoresinol 4-O-alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranoside (1) together with six known compounds, isolariciresinol 9-O-beta-D-glucopyranoside (2), apigenin 6,8-di-C-beta-D-glucopyranoside (3), luteolin 7-O-neohesperidoside (4), luteolin 7-O-beta-D-glucopyranoside (5), 5-methoxyluteolin 7-O-beta-D-glucopyranoside (6), and rutin (7), were isolated from the aerial parts of Urtica laetevirens Maxim. All of the above compounds were isolated from this plant for the first time.

Flavonoids from seeds of Camellia semiserrata Chi. and their estrogenic activity.

Two new flavonol glycosides and three known flavonoids were isolated from seeds of Camellia semiserrata Chi. The structures of these new flavonol glycosides were established as kaempferol 3-O-[(2'''''',3'''''',4''''''-triacetyl)-alpha-L-rhamnopyranosyl(1-->3)(2'''',4''''-diacetyl)-alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranoside] and kaempferol 3-O-[(3'''''',4''''''-diacetyl)-alpha-L-rhamnopyranosyl(1-->3)(2'''',4''''-diacetyl)-alpha-L-rhamnopyranosyl(1-->6)-beta-D-glucopyranoside] by spectroscopic methods. The estrogenic activity of these compounds was investigated by a recombinant yeast screening assay.

[Studies on phenolic compounds from Stellera chamaejasme].

OBJECTIVE: To study the chemical constituents of the roots of Stellera chamaejasme. METHOD: The chemical constituents were separated and purified by chromatographic method after solvent extraction and were identified by spectroscopic analysis. RESULT: Two phenolic compounds were obtained and determined as stelleranol (1) and umbelliferone-7-O-glucoside (2). CONCLUSION: Compound 1 was a new compound, and compound 2 was isolated from this plant for the first time.

[Study on the theraputic effect of plants of Camellia genus on osteoporosis].

OBJECTIVE: To observe anti-osteoporotic effect of Plants of Camelia genus induced by retinoic acid in rats, in adqulis crude drug dosage, and to compare activities of them. METHODS: Extracts of Camellia japonica and Camellia oleifera were given to rats with osteoporosis induced by retinoic acid, some indexes of rats were measured and compared with those of modle group, control group and positive control group, including weight/length (G/L), bone density, earth and calcium content of bone, morphology change and serum calcium, tartrate-resistant acid phosphatase and alkaline phosphatase. We also compared effective intensity between different groups in adqulis crude drug dosage. RESULTS: Ethanol extracts of seed from Camellia japonica 0.51 g/kg could markedly enhance weight/length (G/L), bone density of femur, serum calcium and alkaline phosphatase level, with the decreasing of anti-tartaric acid tartrate-resistant acid phosphatase level. Meanwhile, they were accompanied by a significant increase of morphologic observed sclerotomal cell and by a significant decrease of osteoclast. Moreover, it was observed greatly that bone trabecula transformateed to normal morphous. The results of this study indicated that effects of ethanol extracts of seed from Camellia japonica on anti-osteoporosis with retinoic acid were the strongest. Ethanol extracts of seed from Camellia japonica , ethanol extracts of leaves from Camellia Oleifera, and aqueous extracts of leaves from Camellia Oleifera were stronger than positive control drug. The other extracts didnt show obvious anti-osteoporotic effects. Eventually the strength order of each group on anti-osteoporosis was as following: ethanol extracts of seed from Camellia japonica > ethanol extracts of leaves from Camellia Oleifera > aqueous extracts of leaves from Camellia Oleifera > aqueous extracts of seed from Camellia Oleifera > positive control drug > aqueous extracts of seed from Camellia Japonica. CONCLUSION: Plants of Camellia genus have different degree anti-osteoporosis effect, which can offer significant theory basis for progressive investigation and exploitation of them.