The Salvia miltiorrhiza NAC transcription factor SmNAC1 enhances zinc content in transgenic Arabidopsis.

NAC transcription factors play important roles in plant biological processes, including plant development, environmental stress responses and element enrichment. A novel NAC transcription factor gene, designated SmNAC1, was isolated from Salvia miltiorrhiza. SmNAC1 was localized in the nucleus in onion protoplasts and exhibited transcriptional activation activities in yeast. In addition, the SmNAC1 protein could specifically bind to the cis-elements of the NAC proteins. SmNAC1 was expressed at a higher level in the leaves of S. miltiorrhiza, indicating that SmNAC1 might be involved in the transportation of zinc. To examine the function of SmNAC1, transgenic Arabidopsis plants overexpressing SmNAC1 were generated. Zinc content assays in the transgenic plants demonstrated that overexpressed SmNAC1 plants had enhanced tolerance to high zinc concentrations, and zinc was enriched in the shoot tissues. Our results demonstrate that SmNAC1 plays important roles in the response to zinc stress. Zinc was mainly enriched in the leaves of S. miltiorrhiza and the shoot tissues of transgenic Arabidopsis plants. SmNAC1 might participate in zinc transportation from the roots to the shoots, that constitutes a useful gene for improving zinc content in plants.

Screening of analgesic and anti-inflammatory active component in Fructus Alpiniae zerumbet based on spectrum-effect relationship and GC-MS.

Fructus Alpiniae zerumbet is widely used in Guizhou province as a miao folk herb with anti-inflammatory, analgesic, protection against cardiovascular diseases, antihypertension and antioxidant activities. To further investigate the chemical material basis, the spectrum-effect relationship was established using gray relational analysis between the chromatographic fingerprint and its bioactivities. Herein, the fingerprints of essential oils from Fructus Alpiniae zerumbet (EOFAZ) from various sources were determined by gas chromatography mass spectrometry, and the analgesic and anti-inflammatory bioactivities were investigated using the mouse model of acetic acid-induced writhing test and dimethylbenzene-induced mouse ear edema test. Finally, 17 common peaks were identified from nine batches of A. zerumbet, by comparison with the standard mass spectra in Nist2005, Wiley275 library. Meanwhile, the results showed significant analgesic and anti-inflammatory effects in all of the different sources of EOFAZ. In particularly, peak 1 (α-pipene), peak 3 (ß-pinene), peak 9 (camphor) and peak 16 (α-cadinol) might be the main bioactive ingredients for analgesic and anti-inflammatory activities. The model of the spectrum-effect relationships of EOFAZ was successfully discovered, which provided a novel platform for finding the bioactive components, a theoretical foundation for its further study and helping to establish quality control of Fructus A. zerumbet.

Innate immunity in pluripotent human cells: attenuated response to interferon-ß.

Type I interferon (IFN-α/ß) binds to cell surface receptors IFNAR1 and IFNAR2 and triggers a signaling cascade that leads to the transcription of hundreds of IFN-stimulated genes. This response is a crucial component in innate immunity in that it establishes an "antiviral state" in cells and protects them against further damage. Previous work demonstrated that, compared with their differentiated counterparts, pluripotent human cells have a much weaker response to cytoplasmic double-stranded RNA (dsRNA) and are only able to produce a minimal amount of IFN-ß. We show here that human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) also exhibit an attenuated response to IFN-ß. Even though all known type I IFN signaling components are expressed in these cells, STAT1 phosphorylation is greatly diminished upon IFN-ß treatment. This attenuated response correlates with a high expression of suppressor of cytokine signaling 1 (SOCS1). Upon differentiation of hESCs into trophoblasts, cells acquire the ability to respond to IFN-ß, and this is accompanied by a significant induction of STAT1 phosphorylation as well as a decrease in SOCS1 expression. Furthermore, SOCS1 knockdown in hiPSCs enhances their ability to respond to IFN-ß. Taken together, our results suggest that an attenuated cellular response to type I IFNs may be a general feature of pluripotent human cells and that this is associated with high expression of SOCS1.

New steroidal saponins from the bulbs of Lilium brownii var. viridulum.

Phytochemical investigation of the bulbs of Lilium brownii var. viridulum led to the isolation of seven new steroidal saponins (1-7), along with eight known analogues (8-15). The new steroidal saponins were identified as 27-O-[(3S)-3-O-ß-D-glucopyranosyl 3-methylglutaroyl]isonarthogenin 3-O-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (1), (24S,25S)-3ß,17α,24-trihydroxy-5α-spirostan-6-one 3-O-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (2), tenuifoliol 3-O-[ß-D-glucopyranosyl-(1→4)]-ß-D-glucopyranoside (3), 26-O-ß-D-glucopyranosylnuatigenin (4), 26-O-ß-D-glucopyranosylnuatigenin 3-O-ß-D-glucopyranoside (5), 26-O-ß-D-glucopyranosylnuatigenin 3-O-{α-L-rhamnopyranosyl-(1→2)-[ß-D-glucopyranosyl-(1→6)]}-ß-D-glucopyranoside (6), 26-O-[ß-D-glucopyranosyl-(1→2)]-ß-D-glucopyranosylnuatigenin 3-O-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (7), using a combination of spectroscopic evidence and chemical methods. The carbohydrate chain of a sugar linked to C-3 of the HMG group (3-hydroxy-3-methylglutarate) in compound 1 is rarely found in nature. Compound 2 possesses a new (24S,25S)-3ß,17α,24-trihydroxy-5α-spirostan-6-one aglycon moiety. The disaccharide chain linked to C-26 hydroxy group of the furospirostanol in compound 7 has not been observed from natural sources.

Two new chlorophenyl glycosides from the bulbs of Lilium brownii var. viridulum.

Two rare new chlorophenyl glycosides, 2,4,6-trichlorol-3-methyl-5-methoxy-phenol 1-O-ß-D-glucopyranosyl-(1 → 6)-ß-D-glucopyranoside (1) and 4-chlorol-5-hydroxyl-3-methyl-phenol 1-O-α-L-rhamnopyranosyl-(1 → 6)-ß-D-glucopyranoside (2), along with three known compounds (3-5) were isolated from the bulbs of Lilium brownii var. viridulum. The structures of the new compounds were elucidated on the basis of spectroscopic and chemical methods. All the compounds exhibited weak inhibition of NO production in LPS-stimulated RAW 264.7 cells.