Proteomic insights into protostane triterpene biosynthesis regulatory mechanism after MeJA treatment in Alisma orientale (Sam.) Juz.

Protostane triterpenes in Alisma orientale (Sam.) Juz. have unique structural features with distinct pharmacological activities. Previously we have demonstrated that protostane triterpene biosynthesis could be regulated by methyl jasmonate (MeJA) induction in A. orientale. Here, proteomic investigation reveals the MeJA mediated regulation of protostane triterpene biosynthesis. In our study, 281 differentially abundant proteins were identified from MeJA-treated compared to control groups, while they were mainly associated with triterpene biosynthesis, α-linolenic acid metabolism, carbohydrate metabolism and response to stress/defense. Key enzymes 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR), squalene epoxidase (SE), oxidosqualene cyclase (OSC) and cytochrome P450s which potentially involved in protostane triterpene biosynthesis were significantly enriched in MeJA-treated group. Basic Helix-loop-helix (bHLH), MYB, and GRAS transcription factors were enhanced after MeJA treatment, and they also improved the expressions of key enzymes in Mevalonate pathway and protostane triterpene. Then, MeJA also could increase the expression of α-galactosidase (α-GAL), thereby promoting carbohydrate decomposition, and providing energy and carbon skeletons for protostane triterpene precursor biosynthesis. As well, exogenous MeJA treatment upregulated 13-lipoxygenase (13-LOX), allene oxide synthase (AOS) and allene oxide cyclase (AOC) involved in α-linolenic acid metabolism, leading to the accumulation of endogenous MeJA and activation of the protostane triterpene biosynthesis transduction. Finally, MeJA upregulated stress/defence-related proteins, as to enhance the defence responses activity of plants. These results were further verified by quantitative real-time PCR analysis of 19 selected genes and content analysis of protostane triterpene. The results provide some new insights into the role of MeJA in protostane triterpene biosynthesis.

Effect of temozolomide combined with curcumin on the apoptosis of the C6 glioma cells / 实用医学杂志

Objective To study the temozolomide combined with curcumin on the inhibitory effect and apoptosis of the C6 glioma cells. Methods The C6 glioma cells were treated with temozomide in combination with curcumin. The anti proliferation effect of liposomes on the C6 glioma cells was investigated by using the method of sulforhodamine B (SRB). Flow cytometry was used to detect apoptosis of the C6 glioma cells. Confocal laser scan-ning microscope was used to observe apoptosis and location in the C6 glioma cells. Results The results of SRB as-say showed that temozolomide in combination with curcumin inhibition rate were (91.22 ± 0.51)%in 48 h of the C6 glioma cells; Flow cytometry showed that the apoptosis rate were (33.15 ± 0.79)% with temozolomide (5 μmol/L) in combination with curcumin (10 μmol/L). Laser scanning confocal scanning microscope indicated that the apop-tosis of in the C6 glioma cells treated with temozolomide in combination with curcumin was more than that of free drug. Conclusion The temozolomide in combination of curcumin can inhibit the growth and induce apoptosis of the C6 glioma cells.

Study on Dormancy of Taxus Mairei(Lemee et Levl.) S. Y. Hu ex Liu Seeds / 浙江中医药大学学报

[Objective] To determine dormancy mechanism of Taxus mairei(Lemee et Levl.) S.Y.Hu ex Liu Seeds,the best method of dormancy breaking.[Method]The seeds were handled by lotic water or excitatory autacoid or cold-warm-cold stratification treatment or cold-warm-cold stratification treatment with excitatory autacoid,then compare withgermination inhibition of Brassica campestris seeds handling with water solution from the seeds after four dormancy breaking methods,to dertemine the best dormancy breaking method.[Conclusion] The best damancy breaking method was cold(4℃)—warm(23℃)—cold(4℃) stratification treatment with 0.05% gibberellic acid for 120 days.