Résumé
Aim To explore the hypolipidemic mechanism of the total phenylpropanoid glycoside from Ligustrum robustum (Roxb. ) Blume (LRTPG) on hyperlipidemic hamsters using label-free quantitative proteomic technique. Methods The total protein was extracted from livers of model group and the group treated with LRTPG for label-free quantitative proteomics research. Results The proteomic data showed that a total of 2231 proteins were identified. And 549 proteins were found to be differentially expressed between model group and group treated with LRTPG. Among the 549 proteins, 93 proteins were up-regulated and 59 proteins were down-regulated, and 397 proteins had quantitative values only in model group or drug-administered group. Further, gene ontology (GO) analysis indicated that those differentially expressed proteins were primarily involved in an array of biological processes including metabolism, transport, oxidation-reduction, phosphorylation, signal transduction and lipid metabolism. KEGG pathway analysis revealed that these proteins were involved in several signal pathways including oxidative phosphorylation, non-alcoholic fatty liver dis-ease, PI3K-Akt, cAMP, and cGMP-PKG pathway. And some of these proteins were much related to the lipid metabolism, such as CD36, PK, HSS, GCK, ApoA I, Acly and FABP5. Conclusion The hypolipidemic effect of LRTPG may be related to CD36, PK, HSS, GCK, ApoA I, Acly and FABP5.
Résumé
1-Deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) is the second rate-limiting enzyme of terpenoid biosynthesis in the methylerythritol-4-phosphate pathway. According to the transcriptome database of Cinnamomum camphora, the DXR cDNA was cloned by rapid amplification of cDNA ends (RACE) from C. camphora, and was named CcDXR1 (GenBank number:KU886266). The ORF of CcDXR1 is composed of 1 413 bp, and it encodes 470 amino acids. The bioinformatics analysis suggests that the molecular weight of the encoded protein is 51.1 kD and the theoretically isoelectric point is 6.62, and there is no signal peptide and transmembrane structure in putative protein. The analysis of sequence alignment and phylogenetic tree showed that the CcDXR1 belonged to the DXR family. The results of the realtime PCR indicated that expression level of CcDXR1 in mature leaves was higher than tender leaves, which in roots was similar to leaves and the lowest in branches. The camphor is divided into five chemotypes, according to the main chemical compounds in C. camphora. It also showed that the expression level of CcDXR1 in borneol C. camphora was highest than that in cineol, iso-nerolidol, camphor and linalool. Our results revealed that the expression level of CcDXR1 exhibits diversity among plant tissues, growth periods and five chemical types, and the research provides foundation for further study of the terpenoids biosynthetic pathway in C. camphora.