Combined untargeted and targeted lipidomics approaches reveal potential biomarkers in type 2 diabetes mellitus cynomolgus monkeys.

BACKGROUND: The significantly increasing incidence of type 2 diabetes mellitus (T2DM) over the last few decades triggers the demands of T2DM animal models to explore the pathogenesis, prevention, and therapy of the disease. The altered lipid metabolism may play an important role in the pathogenesis and progression of T2DM. However, the characterization of molecular lipid species in fasting serum related to T2DM cynomolgus monkeys is still underrecognized. METHODS: Untargeted and targeted LC-mass spectrometry (MS)/MS-based lipidomics approaches were applied to characterize and compare the fasting serum lipidomic profiles of T2DM cynomolgus monkeys and the healthy controls. RESULTS: Multivariate analysis revealed that 196 and 64 lipid molecules differentially expressed in serum samples using untargeted and targeted lipidomics as the comparison between the disease group and healthy group, respectively. Furthermore, the comparative analysis of differential serum lipid metabolites obtained by untargeted and targeted lipidomics approaches, four common serum lipid species (phosphatidylcholine [18:0_22:4], lysophosphatidylcholine [14:0], phosphatidylethanolamine [PE] [16:1_18:2], and PE [18:0_22:4]) were identified as potential biomarkers and all of which were found to be downregulated. By analyzing the metabolic pathway, glycerophospholipid metabolism was associated with the pathogenesis of T2DM cynomolgus monkeys. CONCLUSION: The study found that four downregulated serum lipid species could serve as novel potential biomarkers of T2DM cynomolgus monkeys. Glycerophospholipid metabolism was filtered out as the potential therapeutic target pathway of T2DM progression. Our results showed that the identified biomarkers may offer a novel tool for tracking disease progression and response to therapeutic interventions.

bHLH transcription factor SmbHLH92 negatively regulates biosynthesis of phenolic acids and tanshinones in Salvia miltiorrhiza.

Objective: Salvia miltiorrhiza is a valuable herbal medicine with tanshinone and phenolic acid as the main biological active ingredients. The biosynthetic regulation of these bioactive compounds is controlled by a set of transcription factors (TFs). The basic helix-loop-helix (bHLH) transcription factor plays an important role in various physiological and biochemical processes in plants. However, research on bHLH TFs regulating phenolic acid or tanshinone biosynthesis in S. miltiorrhiza is limited. Methods: qRT-PCR was used for gene expression analysis. The subcellular localization of SmbHLH92 was detected by SmbHLH92-GFP transient transformation into tobacco leaves, and its fluorescence was observed using a confocal laser scanning microscope. The transcriptional activity of SmbHLH92 was confirmed in the AH109 yeast strain. RNA interference hairy roots of SmbHLH92-RNAi transgenic lines were obtained through Agrobacterium-mediated genetic transformation. Ultra performance liquid chromatography (UPLC) was used to detect the changes of phenolic acids and tanshinones. Results: SmbHLH92 is a bHLH transcription factor that is highly expressed in the root and phloem of S. miltiorrhiza. The subcellular localization and transcriptional activity of SmbHLH92 indicated that SmbHLH92 was located in the nucleus and may be a transcription factor. RNA interference (RNAi) of SmbHLH92 in hairy roots of S. miltiorrhiza significantly increased the accumulation of phenolic acid and tanshinone. Quantitative RT-PCR (RT-qPCR) analysis showed the transcription level of genes encoding the key enzymes involved in the phenolic acid and tanshinone biosynthetic pathways was increased in the hairy roots of the SmbHLH92-RNAi transgenic line, comparing with the control line. Conclusion: These data indicate that SmbHLH92 is a negative regulator involved in the regulation of phenolic acid and tanshinone biosynthesis in S. miltiorrhiza.

[Cloning and bioinformatics analysis of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase（PcHDR1）gene in Phlegmarirus carinatus].

The open reading frame of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (HDR) was cloned from Phlegmarirus carinatus by RT-PCR method and the sequence was analyzed by bioinformatics tools. After searching the transcriptome dataset of P. carinatus, one unique sequence encoding 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase was discovered. The primers were designed according to the cDNA sequence of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase from the dataset. And then, the open reading frame (ORF) of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase, named as PcHDR1 (GenBank Accession number：JQ957845), was cloned by RT-PCR strategy with the template of mixed RNA extracted from roots, stem and leaf of P. carinatus. The bioinformatic analysis of this gene and its corresponding protein was performed. The ORF of PcHDR1 consisted of 1 437 base pairs (bp), encoding one polypeptide with 478 amino acids. The sequence comparison showed that PcHDR1 is closest with GbHDR (Ginkgo biloba),and the sequence homology was up to 78%. Bioinformatics prediction and analysis indicated that PcHDR1 protein contained a conserved domain of LytB, without transmembrane region and signal peptides. This study cloned and analyzed 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase from P. carinatus. The result will provide a foundation for exploring the function of PcHDR1 involved in terpene biosynthesis in P. carinatus plants.