Rhei Radix et Rhizoma is one of the most used medicinal materials in China. Its original species are Rheum palmatum, Rh. tanguticum, and Rh. officinale. Rhei Radix et Rhizoma derived from different original species are significantly different in their active ingredients and pharmacological effects. To develop an accurate, rapid, and specific identification method, we obtained the chloroplast genomes of the three original species by Illumina Novaseq sequencing. We designed specific DNA barcodes from the hypervariable regions, which can accurately identify the three original species. The experimental results showed that the total length of the chloroplast genomes of Rh. tanguticum, Rh. officinale and Rh. palmatum were 161 039 bp, 161 093 bp, and 161 136 bp, respectively. All the three genomes were represented as typical quadripartite structures. A total of 131 genes, including 86 protein-coding genes, 37 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes were identified from each chloroplast genome. Five pairs of primers based on the hypervariable regions were designed to efficiently amplify 42 samples. Results confirmed that five hypervariable regions, rps16-trnQ, psaA-ycf3, psbE-petL, ndhF-rpl32, and trnT-trnL, can be used as specific DNA barcodes for the identification of Rh. tanguticum, Rh. officinale, and Rh. palmatum. These results provided genetic information for further species identification of Rhei Radix et Rhizoma, and improve the safety of this clinical medication as well as standardize the market for Rhei Radix et Rhizoma.

Two compounds were isolated from 95% ethanol extract of the gum resin of Boswellia carterii by silica gel column chromatography (CC) and high-performance liquid chromatography (HPLC). Their structures were identified with IR, UV, NMR and HR-ESI-MS spectroscopic data as 7α-hydroxy-3, 11-dioxo- tirucalla-8, 24-dien-21-oic acid (1) and 21β-hydroxy-3-acetyl-11-keto-β-boswellic acid (2). In addition, their absolute configurations were also identified by ECD calculations. Among them, compound 1 is a new compound and the absolute configuration of compound 2 is confirmed by ECD calculation for the first time.

Age-related macular degeneration (AMD) is one of the main causes of vision loss among middle-aged and elderly people worldwide. The prevention and treatment of AMD is a current topic of interest in ophthalmology but remains challenging. Oxidative stress-induced retinal pigment epithelial cell autophagic dysfunction, cellular senescence, and an abnormal immune inflammatory response are key pathogenic factors for AMD. Many bioactive ingredients of traditional Chinese medicine not only exert anti-oxidative, anti-inflammatory, anti-aging, and anti-apoptotic effects, but also prevent/block the occurrence of AMD through different pathways. This review summarizes our current understanding of the pathogenesis of AMD, the types of natural bioactive ingredients capable of treating AMD, as well as the known mechanisms by which these agents act, and may provide new strategies for the prevention and treatment of AMD.

The amorphous solid dispersion is one of the most effective formulation approaches to enhance the oral bioavailability of poorly water-soluble drugs. However, the amorphous drugs tend to crystallize during storage or dissolution due to inadequate formulations, preparation techniques, storage and dissolution conditions, thus negating their advantages. Meanwhile, it is often difficult to establish in vitro-in vivo correlation for amorphous solid dispersions owing to the difference between dissolution media and physiological environments and between the apparent concentration and membrane transport flux, the dynamic process of the in vivo absorption, which put great challenges to the development of amorphous solid dispersion products. This review covers the recent progress on the mechanistic study of the in vitro dissolution and in vivo absorption of amorphous solid dispersions, aiming to provide guidance for the formulation development of poorly soluble drugs.

The purpose of this study was to investigate the effect of isorhyncophylline on hippocampal endogenous metabolites in spontaneously hypertensive rats (SHR) by ¹H NMR metabolomics and molecular docking. Twelve SHR were randomly divided into a model group and a treatment group. Six Wistar-Kyoto rats were selected as a control group. The rats in the treatment group were administered isorhyncophylline (0.3 mg·kg^-1) while the rats in the other two groups were treated with the same amount of sterilized saline solution. Animal experiment was authorized by the Ethics Committee of Shandong University of Traditional Chinese Medicine (No. SDUTCM20210721002). Hippocampal tissues were removed after administration for 8 weeks and assayed by ¹H NMR based metabolomics technology combined with a pattern recognition method to find characteristic metabolites, and the metabolic targets were retrieved from the Kyoto Encyclopedia of Genes and Genomes database. Molecular docking technology was used to evaluate binding of isorhyncophylline to the core targets. The results of a principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) showed a clear cluster of samples among three groups. There were seven differentially altered metabolites, and glucose metabolism and glutamate metabolism were the principal related pathways. Molecular docking indicated that isorhyncophylline had good binding properties with nine key candidate target proteins. According to the above research results, isorhyncophylline can influence energy metabolism and glutamate metabolism in the hippocampus.

Synephrine is a natural small-molecule alkaloid found in Aurantii fructus immaturus with versatile biological activities, but its derivatives have been rarely studied so far. Based on the multi-target drug design strategy, the phenolic hydroxyl and secondary amino group of synephrine were modified structurally by the molecular splicing method in this study and thus five intermediates and fifteen target molecules were designed and synthesized. These compounds were evaluated with certain human pathogenic bacteria and fungi, and found that the inhibitory activities of IM4 and IM5 against E.coli are comparable to those of eight fluoroquinolones; TM1n showed stronger inhibitory activity against drug-resistant C. trobicans and drug-resistant C. albicans than the positive control drug fluconazole. TM1d and TM1f against C. albicans ATCC90023, TM1o and TM1f against drug-resistant C. albicans, and TM1f against C. parapsilosis ATCC22019 are all comparable to fluconazole, all of which have the potential for in-depth research. In this study, synephrine derivatives with strong inhibitory activities against human pathogenic fungi were discovered for the first time, which provided a new idea for the further study of synephrine.

Proton nuclear magnetic resonance (¹H NMR) based metabolomics was applied to characterize the fecal metabolic profiles of chronic unpredictable mild stress (CUMS)-depression (CUMS-D) and CUMS-resilience (CUMS-R) rats. The fecal biomarkers and metabolic pathways involved in CUMS-D and CUMS-R were screened and identified, revealing the underlying mechanisms of two different responses of the body to the same stresses. Firstly, the classic depression model, i.e. CUMS, was constructed. According to the fecal metabolomics profiles, the model rats were divided into two groups, i.e. the CUMS-D group and the CUMS-R group. And then, the depression statuses of CUMS-D rats and CUMS-R rats were verified by their sucrose preference rates. Lastly, multivariate data analysis was applied to clarify the fecal biomarkers and corresponding metabolic pathways involving in CUMS-D and CUMS-R. The results show that compared with the control rats, the sucrose preference rates of CUMS-D rats were significantly reduced. By contrast, the sucrose preference rates of CUMS-R rats had no significant difference. At the same time, CUMS-D and CUMS-R showed both unique and shared biomarkers and pathways. Three pathways are significantly related to CUMS-D, including taurine and hypotaurine metabolism, alanine, aspartate and glutamate metabolism, and arginine and proline metabolism. Glycerolipid metabolism and tryptophan metabolism are specific pathways related to CUMS-R. This study explores the mechanisms of the emergence of susceptible and resilience of rats under the same stimulus from a metabolomics perspective. The current findings provide not only a new perspective for studying depression, and personalized and precision treatments in clinic, but also the research and development of antidepressants.

Probe electrospray ionization (PESI) is one of the typical types of ambient ionization technology, but its application in quantitative analysis is limited due to its poor sampling stability. Previously, we developed a new micro-pen electrospray ionization tandem mass spectrometry (μPen-ESI-MS/MS) method based on PESI. In this study, a μPen-ESI-MS/MS method to measure testosterone and dextromethorphan in liver microsome samples was developed and validated to further applicate in evaluating drug metabolism stability and CYP450 enzyme activity. A μPen-ESI-MS/MS method for detecting the CYP3A4 substrate testosterone and CYP2D6 substrate dextromethorphan in the liver microsome incubation system were developed, and the linearity, precision and accuracy of the method was validated. The validated method was further used to detect the metabolic stability of testosterone in the liver microsome incubation system. The results showed that the μPen-ESI-MS/MS had high efficiency with 0.3 min spraying time of each sample. The standard curve of the testosterone and dextromethorphan has good linearity (R² > 0.99), the intra- and inter-batch accuracy of testosterone and dextromethorphan was 95.9%-109.3% and 90.5%-107.3%, respectively; the intra- and inter-batch precision was acceptable with RSD values of 2.4%-13.5% and 3.4%-12.1%. The half-lives of testosterone and dextromethorphan in the liver microsome incubation system were 12 min and 14 min, respectively. This study provided a rapid and sensitive μPen-ESI-MS/MS method for the assay of testosterone and dextromethorphan in liver microsome samples, and provided a new strategy for the evaluation of drug metabolism stability and CYP3A4/CYP2D6 activity.

MYB transcription factors, one of the largest transcription factor families in plants, play an important role in signal transduction, plant growth and plant resistance. In this study a full-length cDNA of the PnMYB1R1 gene was cloned from Panax notoginseng. Sequence analysis, prokaryotic expression and purification, subcellular location, transcriptional activity analysis, tissue-specific analysis and expression analysis under different abiotic stresses was performed. The open reading frame (ORF) of PnMYB1R gene was 738 bp, encoding a protein of 245 amino acids with a predicted molecular mass (MW) of 27.0 kD. The sequence analysis and polygenetic analysis indicated that the PnMYB1R1 protein contains a conserved R3 domain, belonging to TRF-like protein in 1R-MYB-type transcription factors. The recombinant PnMYB1R1 protein was expressed in Escherichia coli BL21(DE3) cells using the prokaryotic expression vector pET28a-PnMYB1R1 and was purified. Subcellular localization analysis showed that PnMYB1R1 was localized in the nucleus. Transcriptional activity analysis indicated that the PnMYB1R1 transcription factor has transcriptional activation activity. Expression analysis indicated that PnMYB1R1 was primarily expressed in roots, followed by stems and leaves, and then rootlets. The expression level of PnMYB1R1 in root, stems, leaves and rootlets was influenced by salt, low temperature and drought treatment, while the abundance of PnMYB1R1 was significantly induced by salt stress in these tissues. These results provide valuable insights into the role of 1R-MYB transcription factors in plant defense.

Berberine is a naturally occurring benzylisoquinoline alkaloid with a wide range of pharmacological activities, such as antibacterial, anticancer, hypolipidemic, antidiabetic and antidiarrheal. Although berberine has a wide range of curative effects, the extremely low bioavailability (< 1%) limits its clinical application. Pure berberine preparations have not yet been approved for any specific disease. The low oral bioavailability of berberine is mainly due to poor solubility caused by self-aggregation under acidic conditions, low permeability, P-glycoprotein (P-gp)-mediated efflux, and liver and intestine metabolism. To improve the oral bioavailability of berberine, researchers have adopted a variety of strategies, including the application of various nano-delivery systems, penetration enhancers and P-gp inhibitors, structural modifications, and development of berberine derivatives. Improving the oral bioavailability of berberine can improve the pharmacological activity of berberine, reduce the dosage, and then reduce the toxic and side effects. This review summarized the various pharmacological activities, metabolism progress and pharmacokinetic characteristics of berberine, the newly discovered berberine target intestinal microbiota and focused on the strategies to improve the oral bioavailability of berberine by improving solubility and permeability, inhibiting P-gp efflux, and structural modification. The research on berberine was prospected, which provided guidance for the in-depth study of berberine.