De novo and comparative transcriptomic analysis explain morphological differences in Panax notoginseng taproots

Integrated transcriptomic and WGCNA analyses reveal candidate genes regulating mainly flavonoid biosynthesis in Litsea coreana var. sinensis

Litsea coreana Levl. var. sinensis (Allen) Yang et P. H. Huang is a popular ethnic herb and beverage plant known for its high flavonoid content, which has been linked to a variety of pharmacological benefits and crucial health-promoting impacts in humans. The progress in understanding the molecular mechanisms of flavonoid accumulation in this plant has been hindered due to the deficiency of genomic and transcriptomic resources. We utilized a combination of Illumina and Oxford Nanopore Technology (ONT) sequencing to generate a de novo hybrid transcriptome assembly. In total, 126,977 unigenes were characterized, out of which 107,977 were successfully annotated in seven public databases. Within the annotated unigenes, 3,781 were categorized into 58 transcription factor families. Furthermore, we investigated the presence of four valuable flavonoids-quercetin-3-O-β-D-galactoside, quercetin-3-O-β-D-glucoside, kaempferol-3-O-β-D-galactoside, and kaempferol-3-O-β-D-glucoside in 98 samples, using high-performance liquid chromatography. A weighted gene co-expression network analysis identified two co-expression modules, MEpink and MEturquoise, that showed strong positive correlation with flavonoid content. Within these modules, four transcription factor genes (R2R3-MYB, NAC, WD40, and ARF) and four key enzyme-encoding genes (CHI, F3H, PAL, and C4H) emerged as potential hub genes. Among them, the R2R3-MYB (LcsMYB123) as a homologous gene to AtMYB123/TT2, was speculated to play a significant role in flavonol biosynthesis based on phylogenetic analysis. Our findings provided a theoretical foundation for further research into the molecular mechanisms of flavonoid biosynthesis. Additionally, The hybrid transcriptome sequences will serve as a valuable molecular resource for the transcriptional annotation of L. coreana var. sinensis, which will contribute to the improvement of high-flavonoid materials.

Research progress on the pharmacological effects and chemical constituents of Pien Tze Huang and its potential Q-markers

Pien Tze Huang (PTH) was documented as an imperial prescription composed of Notoginseng Radix, Calculus Bovis, Snake Gallbladder, and Musk. It is famous in China and Asian countries due to its excellent effects in heat clearing, detoxifying, swelling reduction, and pain relieving. Modern pharmacological studies demonstrate that PTH shows excellent effects against various inflammatory diseases, liver diseases, and cancers. This review summaries the pharmacological effects, clinical applications, and mainchemical components of PTH. More importantly, its potential quality markers (Q-markers) were then analyzed based on the "five principles" of Q-markers under the guidance of Traditional Chinese Medicine theory, including transfer and traceability, specificity, efficacy, compatibility, and measurability. As a result, ginsenosides Rb1, ginsenoside Rg1, ginsenoside Rd, ginsenoside Re, notoginsenoside R1, dencichine, bilirubin, biliverdin, taurocholic acid, and muscone are considered as the Q-markers of PTH. These findings will provide guidance and assistance for the construction of a quality control system for PTH.

Panax notoginseng Saponins Alleviate Coronary Artery Disease Through Hypermethylation of the miR-194-MAPK Pathway

Background:Panax notoginseng saponins (PNS) may have an inhibitory effect against coronary artery disease (CAD); however, the mechanism is unclear. Recent research has begun to evaluate the role of epigenetics in CAD. Our team found that hypomethylation of miR-194 could be an important mechanism of CAD.

Purpose: The aim of this study was to investigate the effect of PNS against CAD and evaluate whether the mechanism is related to methylation of mi-R194.

Methods: We conducted a randomized controlled trial with a double-blind placebo design on 84 patients with CAD. Treatment was continued for 4 weeks, and the clinical effect of PNS on CAD was observed. Methylation of miR-194, its promoter, and the key nodes of the MAPK pathway were measured by pyrosequencing and qRT-PCR. We then conducted a pharmacological analysis of the active components of PNS. The effects of PNS on oxidized human umbilical vein endothelial cells and the methylation of miR-194, its promoter, and the key nodes of the MAPK pathway were measured in vitro through methylation-specific PCR (MSPCR), qRT-PCR, Western blot analysis, and annexin V/propidium iodide apoptosis assay.

Results: PNS improved symptoms of CAD. High-density lipoprotein and white blood cell count demonstrated significant changes after treatment in the PNS group. No significant difference was observed between miR-194 and mRNA MAPK, FAS, RAS, and FOS in the PNS group after treatment. However, some notable trends were observed in these genes. The targets of PNS were predicted by the pharmacological components. Some targets were found to be differentially expressed genes in CAD sequencing. Six genes, including MAPK1, RAS, and FASL, were common targets of PNS in CAD sequencing. Correlations were observed between genes in the interaction network and clinical parameters. In vitro experiments confirmed that PNS could change the methylation of miR-194, its promoter, and MAPK, FAS, RAS, and FOS. Intervention with PNS is likely to improve apoptosis.

Conclusion: We reported the regulation of miR-194 promoter, miR-194, and MAPK methylation by PNS through cell experiments and a randomized controlled trial. PNS can be used for intervention in CAD by targeting the miR-194 promoter-miR-194-MAPK signaling pathway.

Clinical Trial Registration: https://www.clinicaltrials.gov/, NCT03083119.