Oleanane-Type Saponins Biosynthesis in Panax notoginseng via Transformation of ß-Amyrin Synthase Gene from Panax japonicus.

Oleanane-type saponins considered as the main medicinal ingredients in Panax japonicus are not found in Panax notoginseng. ß-Amyrin synthase (ßAS) was recognized as the first key enzyme in the biosynthetic branch of oleanane-type saponins. In this study, ßAS gene from P. japonicus ( PjßAS) was transferred into P. notoginseng cells. Along with PjßAS expression in the transgenic cells, the expression levels of several key enzyme genes related to triterpenoid saponins biosynthesis and the content of P. notoginseng saponins were also increased. Two oleanane-type saponins, chikusetsusaponin IV and chikusetsusaponin IVa, contained in P. japonicus were first discovered in transgenic P. notoginseng cells. This study successfully constructed a biosynthetic pathway of oleanane-type saponins in P. notoginseng by introducing just one gene into the species. On the basis of this discovery and previous studies, the common biosynthetic pathway of triterpenoid saponins in Panax genus may be unified to some extent.

A ferritin gene from Procambarus clarkii, molecular characterization and in response to heavy metal stress and lipopolysaccharide challenge.

Ferritin plays important roles in iron storage, detoxification, and immune response. Here, a ferritin gene (PcFer) was identified in Procambarus clarkii, an economically important freshwater crayfish. Full-length PcFer cDNA was 1022-bp, including a 135-bp 5'-untranslated region (UTR) with a typical iron responsive element, a 374-bp 3'-UTR, and a 513-bp open reading frame encoding a polypeptide of 170 amino acids which contained the Ferritin domain. PcFer has ion binding sites, a ferrihydrite nucleation center, and an iron ion channel. PcFer is phylogenetically closely-related to Pacifastacus leniusculus and Eriocheir sinensis ferritins. Real-time quantitative reverse-transcription PCR analysis showed that PcFer was expressed in all tested P. clarkii tissues, and expressed most in hepatopancreas. After challenge with various heavy metals and lipopolysaccharide, respectively, the hepatopancreatic expression levels of PcFer were markedly upregulated. These results suggest that expression of PcFer might be involved in immune defense and protection of P. clarkii against heavy metal stress.

Terpenoid composition and the anticancer activity of Acanthopanax trifoliatus.

The petroleum ether and ethyl acetate fractions of extract from an edible and medicinal plant Acanthopanax trifoliatus were found to show significant inhibitory effects against SF-268, MCF-7, HepG2 and NCI-H460 cancer cells. Two new ursane-type triterpenoids, acantrifoic acid C (1) and acantrifoic acid D (2), along with five known triterpenoids (3-7) and eight known diterpenoids (8-15) were obtained from these two fractions. To the best of our knowledge, this is the first report concerning the isolation of compounds (5-12, 14, 15) from A. trifoliatus. Among all the isolated compounds, 3, 5 and 8 from the ethyl acetate fraction showed the strongest inhibitory effects against cancer cells, while 12 and 13 from the petroleum ether fraction showed moderate activities. These terpenoid compounds may be responsible for the anticancer activities of A. trifoliatus. Our study provides the first evidence that terpenoids from A. trifoliatus exert anticancer activities and indicates that A. trifoliatus may be a useful edible plant for further development of anticancer health supplement.

Vitamin K3 increased BMD at 1 and 2 months post-surgery and the maximum stress of the middle femur in the rat.

The therapeutic effects of vitamin K3 (VK3) on osteoporosis are still unknown. In this study, we hypothesized that VK3 possesses therapeutic effects on osteoporosis; to verify this hypothesis, the ovariectomized rat was used as an osteoporosis model. Fifty-six Sprague-Dawley female rats aged 8 to 9 months were randomly assigned to 4 groups: sham surgery, ovariectomy with saline, ovariectomy with low-dose VK3, and ovariectomy with high-dose VK3. Intramuscular injection of VK3 was performed every other day beginning 1 month postoperatively. The therapeutic effects of VK3 on osteoporosis were evaluated by measurement of bone mineral density (BMD), bone biochemical markers, biomechanical properties, and bone morphometric parameters. The overall average BMD in VK3-treated groups increased to a level between those of the ovariectomy group and the sham surgery group. The procollagen I N-terminal peptide level peaked at 2 months after surgery in all groups except in the group that had undergone ovariectomy with low-dose VK3. The tartrate-resistant acid phosphatase 5b level increased more slowly at 4 months after surgery than at 2 months after surgery in the VK3-treated groups. The ovariectomy with high-dose VK3 group had the highest maximum stress of the middle femur of all groups. With VK3 treatment, the trabecular bone area percentage increased. All morphometric indicators for the middle tibia in the VK3-treated groups reached the levels found in the sham surgery group. In summary, VK3 therapy increased BMD at 1 and 2 months postsurgery and the maximum stress of the middle femur. In addition, VK3 therapy slowed the increase in bone turnover in ovariectomized rats. Furthermore, VK3 can improve morphometric indicators for the middle tibia. Our preliminary study indicates that VK3 has a potential therapeutic effect on osteoporosis and is worthy of further investigation.

Hyperthermia inhibits hypoxia-induced epithelial-mesenchymal transition in HepG2 hepatocellular carcinoma cells.

AIM: To investigate the effect of hyperthermia on hypoxia-induced epithelial-mesenchymal transition (EMT) in HepG2 hepatocellular carcinoma (HCC) cells, and its mechanism. METHODS: Cells were treated with hyperthermia at 43 °C for 0.5 h, followed by incubation under hypoxic or normoxic conditions for 72 h. Cell morphology was observed. Expressions of E-cadherin and vimentin were determined by immunofluorescence assay or Western blot. The protein and mRNA expressions of Snail were also determined by Western blot and reverse transcription-polymerase chain reaction. Cell migratory capacity was evaluated. RESULTS: Hypoxia induced EMT in HepG2 cells, which was evidenced by morphological, molecular and functional changes, including the formation of a spindle shape and the loss of cell contact. The expression of E-cadherin was decreased but the expression of vimentin was increased; also, the migratory capability was increased by 2.2 ± 0.20-fold as compared with normoxia. However, those effects were inhibited by hyperthermia pretreatment. Furthermore, protein synthesis and mRNA expression of Snail in the cells were enhanced by hypoxia as compared with normoxia, and also significantly inhibited by hyperthermia pretreatment. CONCLUSION: Hyperthermia may inhibit hypoxia-induced EMT in HepG2 HCC cells, and the mechanism may involve inhibition of induced expression of Snail.