Comparison of the Phytochemical Properties, Antioxidant Activity and Cytotoxic Effect on HepG2 Cells in Mongolian and Taiwanese Rhubarb Species

Rhei Undulati Rhizoma attenuates memory decline and reduces amyloid-β induced neuritic dystrophy in 5xFAD mouse

BACKGROUND

Alzheimer's disease (AD) is a common type of dementia characterized by amyloid-β (Aβ) accumulation, lysosomal dysfunction, and tau hyperphosphorylation, leading to neurite dystrophy and memory loss. This study aimed to investigate whether Rhei Undulati Rhizoma (RUR), which has been reported to have anti-neuroinflammatory effect, attenuates Aβ-induced memory impairment, neuritic dystrophy, and tau hyperphosphorylation, and to reveal its mode of action.

METHODS

Five-month-old 5xFAD mice received RUR (50 mg/kg) orally for 2 months. The Y-maze test was used to assess working memory. After behavioral testing, brain tissue was analyzed using thioflavin S staining, western blotting, and immunofluorescence staining to investigate the mode of action of RUR. To confirm whether RUR directly reduces Aβ aggregation, a thioflavin T assay and dot blot were performed after incubating Aβ with RUR.

RESULTS

RUR administration attenuated the Aβ-induced memory impairment in 5xFAD mice. Furthermore, decreased accumulation of Aβ was observed in the hippocampus of the RUR-treated 5xFAD group compare to the vehicle-treated 5xFAD group. Moreover, RUR reduced the dystrophic neurites (DNs) that accumulate impaired endolysosomal organelles around Aβ. In particular, RUR treatment downregulated the expression of β-site amyloid precursor protein cleaving enzyme 1 and the hyperphosphorylation of tau within DNs. Additionally, RUR directly suppressed the aggregation of Aβ, and eliminated Aβ oligomers in vitro.

CONCLUSIONS

This study showed that RUR could attenuate Aβ-induced pathology and directly regulate the aggregation of Aβ. These results suggest that RUR could be an efficient material for AD treatment through Aβ regulation.

Exploration of plant metabolomics variation and absorption characteristics of water-extracted Rheum tanguticum and ethanol-extracted Rheum tanguticum by UHPLC-Q-TOF-MS/MS

BACKGROUND AND OBJECTIVE

The herb Rheum tanguticum (RT), a member of the Polygonaceae family, is listed in the Chinese Pharmacopoeia and has been widely used to treat cardiovascular and gastrointestinal disease. The research aimed to identify the different substances from two kinds of RT extraction methods and the in vivo biotransformation of RT components.

METHODS

In this study, by using ultrahigh-performance liquid chromatography coupled with quadrupole-time-of-flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS), we have investigated the metabolomic variation and the in vivo metabolism of RT. A post-acquisition data processing software, PeakView, was applied to an accurate qualitative analysis of the chemical components in RT.

RESULTS

Through plant metabolomics analysis, 24 related, differentially expressed metabolites of RT water extract and alcohol extract were obtained. Combined with novel identification strategies and systematic in vivo metabolism analysis, a total of 101 compounds were discovered or tentatively identified in rat serum (including 15 prototype compounds and 86 metabolites).

CONCLUSION

In this study, a combination of extraction methods, liquid chromatography-mass spectrometry (LC-MS) technology, and in vivo animal metabolism studies have been established for the screening, identification, and research of chemical active components of natural medicines. LC-MS analysis combined with plant metabolomics was used to study the differential metabolites between different extraction methods of RT. Based on UHPLC-Q-TOF-MS/MS technology, the composition and metabolism of rat plasma before and after RT administration were analysed in vivo, and 15 prototype components and 86 metabolites were detected.

Molecular mechanism of Rhubarb in the treatment of non-small cell lung cancer based on network pharmacology and molecular docking technology

Non-small cell lung cancer (NSCLC) is one of the leading causes of death in the world. Rhubarb, a traditional Chinese medicine, has been widely used in the treatment of inflammatory and autoimmune diseases. This study aimed to investigate the possible mechanism of the rhubarb herb in the treatment of NSCLC by means of network pharmacology and molecular docking and to provide a theoretical basis for experiments and clinical application of traditional Chinese medicine for treating lung cancer. The main active chemical components and targets of rhubarb were screened through Swiss Target Prediction, TargetNet, and Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. The protein-protein interaction (PPI) network was built via an in-depth exploration of the relationships between the proteins. The enrichment analyses of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were applied to predict the potential roles in the pathogenesis of NSCLC via the R package cluster Profiler. Potential targets and active ingredients associated with anti-tumor effects of rhubarb were screened by reverse molecular docking. By searching databases and literature, a total of 295 targets were found for the 21 active ingredients in rhubarb. There were 68 common target genes associated with NSCLC, of which 9 are derived from FDA-approved drugs. GO Gene Set Enrichment Analysis (GSEA) explored up to 1103 biological processes, 62 molecular functions, and 18 cellular components. KEGG GSEA explored 65 basic pathways, and 71 disease pathways. Four key targets (JUN, EGFR, BCL2, and JAK2) were screened through the protein-protein interaction network, target-pathway network, and FDA drug-target network. Molecular docking results showed that these key targets had relatively strong binding activities with rhubarb's active ingredients. The present study explored the potential pharmacological mechanisms of rhubarb on NSCLC, promoting the clinical application of rhubarb in treating NSCLC, and providing references for advanced research.

Phytochemical Profile and Pharmacological Activity of Vernonia amygdalina Delile Stem Bark Extracts Using Different Solvent Extraction

BACKGROUND: Vernonia amygdalina is a native plant from Africa which is widely distributed to Asia, especially in Indonesia. Parts of V. amygdalina such as roots, leaves, and bark are used by the community as traditional medicines such as antidiabetic, antibacterial, and anticancer. AIM: This study aims to show the effect of solvents in the V. amygdalina stem bark extraction process on phytochemical’s content and their correlation with pharmacological activities. METHODS: V. amygdalina extract from stem bark in this study was obtained using the maceration method with different solvents. The extracts were investigated for total phenolic content (TPC) and total flavonoids content (TFC) using calorimetry assay. Principal Component Analysis (PCA) was used to grouping the extracts based on Fourier-transform infrared (FTIR) data. Antioxidant activity of the extracts was done using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis (3-ethyl benzhothiazoline sulphonic acid) (ABTS) assay. While, the cytotoxic activity of the extracts was carried out using MTT assay on PANC-1 cell line. The correlation phytochemical content and pharmacology activities of extracts were analyzed using person correlation method. RESULTS: There were significantly different TPC and total flavonoid content of extracts (p < 0.05). The ethyl acetate extract was identified to have the highest TPC, TFC, DPPH, ABTS, and cytotoxic values of 3.61 ± 0.03 mg GAE/g dry powder, 25.12 ± 0.09 mg QE/g dry powder, 27.12 ± 0.65 μg/mL, 67.02 ± 0.23 μg/mL, and 33.83 ± 0.82 μg/mL, respectively (p < 0.05). This is supported by PCA analysis which shows that there are differences in extracts based on FTIR data and there is a strong correlation between TPC and TFC values with antioxidant and cytotoxic activities. CONCLUSIONS: This study report that each extract of V. amygdalina stem bark gives a distinct phytochemical profile (TPC, TFC, and FTIR spectrum) that contributes to the antioxidant activity and cytotoxic activity.

Comparison of Three Species of Rhubarb in Inhibiting Vascular Endothelial Injury via Regulation of PI3K/AKT/NF-κB Signaling Pathway

Background/Aim

Rhubarb, a traditional Chinese medicine derived from three species, is commonly used in the prescriptions for promoting blood circulation and removing blood stasis based on its traditional effects of removing blood stasis and dredging the meridians. It has been reported that rhubarb can protect blood vessels by reducing inflammation and inhibiting vascular endothelial injury (VEI), but the effective components and mechanism of rhubarb inhibiting VEI are still unclear. This study aimed to compare the differences in chemical compositions of the three species of rhubarb and their inhibitory effect on VEI, so as to explain the material basis and select the dominant species to inhibit VEI, and to elucidate the mechanism of rhubarb's inhibitory effect on VEI.

Methods

Plant metabolomics was used to compare the chemical components of three species of rhubarb. The efficacy of three species of rhubarb in inhibiting VEI was compared through cell experiments in vitro. At the same time, combined with network pharmacology and molecular docking, the effective components and pathways of rhubarb involved in inhibiting VEI were screened. The mechanism of rhubarb inhibiting VEI was verified by molecular biology.

Results

There were significant differences in the distribution of chemical components among the three species of rhubarb. We identified 36 different chemical components in the positive ion mode and 38 different chemical components in the negative ion mode. Subsequently, the results showed significant differences in inhibiting VEI among the three species of rhubarb based on the contents of inflammatory factors (such as IL-1β, IL-6, and TNF-α), ROS, and NO and confirmed that R. tanguticum had the best inhibitory effect on VEI in the light of the comprehensive efficacy, compared with R. palmatum and R. officinale. Three species of rhubarb alleviated the inflammatory response in LPS-induced EA.hy926 cells by reducing the contents of inflammatory cytokines IL-6, IL-1β, and TNF-α and decreasing expressions of PI3K, AKT, NF-κB p65, and STAT3 protein in the PI3K/AKT/NF-κB pathway and the inhibition of proteins phosphorylation. In addition, three species of rhubarb could lessen the contents of ROS and NO in EA.hy926 cells induced by LPS. All results indicated that the process of inflammation-induced cellular oxidative stress, which resulted in VEI, was obviously improved by three species of rhubarb.

Conclusion

R. tanguticum was more effective among three species of rhubarb, and it had been proved that gallic acid, gallic-acid-O-galloyl-glucoside, procyanidin B-2,3,3′-di-O-gallatein, and other potential components could reduce the contents of inflammatory factors (such as IL-1β, IL-6, and TNF-α), ROS, and NO by inhibiting the PI3K/AKT/NF-κB signaling pathway and protected the vascular endothelium and the blood vessels by improving the inflammation and oxidative stress reaction.

7-Hydroxy questin, a new anthraquinone from a wetland fungus Aspergillus flavipes PJ03-11

One new anthraquinone, questinlin (1), four known anthraquinones (2-5), together with three known benzophenone derivatives (6-8) were isolated from a wetland fungus Aspergillus flavipes PJ03-11. Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D, 2D NMR (HMQC, HMBC), mass spectrometry, and optical rotation and IR spectra. In addition, the cytotoxic activities against three human cancer cell lines (HepG2, Caco-2 and A549) were evaluated. In this article, Aspergillus flavipes PJ03-11, a wetland soil fungus isolated from Honghaitan, Panjin city, Liaoning province, was used to study the secondary metabolites through one strain many compounds (OSMAC) methods. By changing the culture medium and adding the substance stimulating the metabolism of the strain into the fermentation medium, the peak type and amount of ethyl acetate extract in the fermentation medium were studied by HPLC. Finally, 2 mM MgCl₂ was added into the rice solid medium for the expansion fermentation.