A high-value-added application of the stems of Rheum palmatum L. as a healthy food: the nutritional value, chemical composition, and anti-inflammatory and antioxidant activities

The phytochemistry and pharmacology of three Rheum species: A comprehensive review with future perspectives

BACKGROUND

Rheum palmatum, R. tanguticum, and R. officinale, integral species of the genus Rheum, are widely used across global temperate and subtropical regions. These species are incorporated in functional foods, medicines, and cosmetics, recognized for their substantial bioactive components.

PURPOSE

This review aims to synthesize developments from 2014 to 2023 concerning the botanical characteristics, ethnopharmacology, nutritional values, chemical compositions, pharmacological activities, mechanisms of action, and toxicity of these species.

METHODS

Data on the three Rheum species were gathered from a comprehensive review of peer-reviewed articles, patents, and clinical trials accessed through PubMed, Google Scholar, Web of Science, and CNKI.

RESULTS

The aerial parts are nutritionally rich, providing essential amino acids, fatty acids, and minerals, suitable for use as health foods or supplements. Studies have identified 143 chemical compounds, including anthraquinones, anthrones, flavonoids, and chromones, which contribute to their broad pharmacological properties such as laxative, anti-diarrheal, neuroprotective, hepatoprotective, cardiovascular, antidiabetic, antitumor, anti-inflammatory, antiviral, and antibacterial effects. Notably, the materials science approach has enhanced understanding of their medicinal capabilities through the evaluation of bioactive compounds in different therapeutic contexts.

CONCLUSION

As medicinal and economically significant herb species, Rheum species provide both edible aerial parts and medicinal underground components that offer substantial health benefits. These characteristics present new opportunities for developing nutritional ingredients and therapeutic products, bolstering the food and pharmaceutical industries.

Physiologically based Kinetic Modeling-Facilitated Quantitative In Vitro to In Vivo Extrapolation to Predict the Effects of Aloe-Emodin in Rats and Humans

Aloe-emodin, a natural hydroxyanthraquinone, exerts both adverse and protective effects. This study aimed at investigating these potential effects of aloe-emodin in humans upon the use of food supplements and herbal medicines using a physiologically based kinetic (PBK) modeling-facilitated quantitative in vitro to in vivo extrapolation (QIVIVE) approach. For this, PBK models in rats and humans were established for aloe-emodin including its active metabolite rhein and used to convert in vitro data on hepatotoxicity, nephrotoxicity, reactive oxidative species (ROS) generation, and Nrf2 induction to corresponding in vivo dose-response curves, from which points of departure (PODs) were derived by BMD analysis. The derived PODs were subsequently compared to the estimated daily intakes (EDIs) resulting from the use of food supplements or herbal medicines. It is concluded that the dose levels of aloe-emodin from food supplements or herbal medicines are unlikely to induce toxicity, ROS generation, or Nrf2 activation in liver and kidney.

Dahuang Zhechong Pill Alleviates Liver Fibrosis Progression by Regulating p38 MAPK/NF-κ B/TGF-β1 Pathway

OBJECTIVE

To explore the effect and mechanism of Dahuang Zhechong Pill (DHZCP) on liver fibrosis.

METHODS

Liver fibrosis cell model was induced by transforming growth factor-β (TGF-β) in hepatic stellate cells (HSC-T6). DHZCP medicated serum (DMS) was prepared in rats. HSC-T6 cells were divided into the control (15% normal blank serum culture), TGF-β (15% normal blank serum + 5 ng/mL TGF-β), DHZCP (15% DMS + 5 ng/mL TGF-β), DHZCP+PDTC [15% DMS + 4 mmol/L ammonium pyrrolidine dithiocarbamate (PDTC)+ 5 ng/mL TGF-β], and PDTC groups (4 mmol/L PDTC + 5 ng/mL TGF-β). Cell activity was detected by cell counting kit 8 and levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the cell supernatant were determined by enzyme-linked immunosorbnent assay. Western blot was used to measure the expressions of p38 mitogen-activated protein kinase/nuclear factor kappa B/transforming growth factor-β1 (p38 MAPK/NF-κ B/TGF-β1) pathway related proteins, and the localization and expressions of these proteins were observed by immunofluorescence staining.

RESULTS

DHZCP improves the viability of cells damaged by TGF-β and reduces inflammatory cytokines and ALT and AST levels in the supernatant of HSC-T6 cells induced with TGF-β (P<0.05 or P<0.01). Compared with the TGF-β group, NF-κ B p65 levels in the DHZCP group were decreased (P<0.05). p38 MAPK and NF-κ B p65 levels in the DHZCP+PDTC were also reduced (P<0.01). Compared with the TGF-β group, the protein expression of Smad2 showed a downward trend in the DHZCP, DHZCP+PDTC, and PDTC groups (all P<0.01), and the decreasing trend of Samd3 was statistically significant only in DHZCP+PDTC group (P<0.01), whereas Smad7 was increased (P<0.05 or P<0.01).

CONCLUSION

DHZCP can inhibit the process of HSC-T6 cell fibrosis by down-regulating the expression of p38 MAPK/NF-κ B/TGF-β1 pathway.

Exploring anticancer properties of the phytoconstituents and comparative analysis of their chemical space parameters with USFDA-approved synthetic anticancer agents

The present review article thoroughly analyses natural products and their derived phytoconstituents as a rich source of plausible anticancer drugs. The study thoroughly explores the chemical components derived from various natural sources, thus emphasizing their unique structural characteristics and therapeutic potential as an anticancer agent. The review contains the critical chemical constituents' in-depth molecular mechanisms, their source's chemical structures and the categories. The review also comprises an exhaustive and comprehensive analysis of different chemical spacing parameters of the anticancer agents derived from natural products. It compares them with USFDA-approved synthetic anticancer drugs up to 2020, thus providing a meaningful understanding of the relationship between natural and synthetic compounds portraying the anticancer assets. The review also delves more deeply into the chemical analysis of the heterocyclic moieties from the natural product arena, illustrating the anticancer mechanisms. The present article is, therefore, expected to serve as a valuable resource for natural product and medicinal chemists, encouraging and promoting an integrated approach to exploit the potential of natural products in drug discovery development and translational research, which have a prerequisite of bench to bedside approach. The work could guide researchers toward innovative approaches for the ever-evolving field of anticancer drug discovery.

Changes in the nutrients, phytochemical profile and antioxidant activity of Rheum officinale Baill. leaf blades during different growth periods

Rhubarb contains an abundance of compounds and nutrients that promote health through various activities; however, these activities are affected by the harvest season. In this paper, the changes in nutrients, phytochemical profiles and antioxidant activity of Rheum officinale leaf blades (LRO) during different growth periods were investigated. The results showed that LRO is a good source of protein, fiber, and minerals and contains abundant fatty acids; however, as the harvest time increased from March to July, the levels of protein and amino acid decreased, and the levels of other nutrients reached a maximum in May or June. LRO also contains flavonoids, terpenoids, and quinones. As the harvest time increased, the quinone content decreased, possibly due to the unstable chemical properties of quinones at high temperatures. The flavonoid contents reached a maximum in May or June. This study indicated that LRO is a source of nutrients and chemical components and can be used for functional food production. In addition, the nutrients and chemical components related to the antioxidant activity of LRO changed according to the harvest season.

Application of two-dimensional reversed phase countercurrent chromatography × high-performance liquid chromatography to bioactivity-guided screening and isolation of α-glucosidase inhibitors from Rheum palmatum L

In the present work, comprehensive two-dimensional reversed-phase countercurrent chromatography × reversed-phase liquid chromatography combined (2D RPCCC × RPLC) with 2D microfraction bioactive evaluation was employed to screen and isolate α-glucosidase inhibitors from Rheum palmatum L. Countercurrent chromatography was employed to improve 2D analysis and preparative separation. A selected biphasic solvent system composed of petroleum ether/ethyl acetate/methanol/water with gradient elution mode was used for the first dimension RPCCC separation (1D RPCCC). Solid-phase extraction was applied to eliminate interfering polar compounds before the second dimension analysis (2D RPLC). 76 components were shown in 2D contour plot in UV 280 nm. 11 Candidates were separated by a scaled-up CCC and identified by 1H NMR and 13C NMR, including anthraquinones, flavonoids, stilbenes, phenols, and glucoside derivatives. In addition, it was found that two components, resveratrol-4'-O-(6″-galloyl)glucoside (36) and lyciumaside (43) were identified as natural α-glucosidase inhibitors in Rheum palmatum L. for the first time.

Cirsiliol and Quercetin Inhibit ATP Synthesis and Decrease the Energy Balance in Methicillin-Resistant Staphylococcus aureus (MRSA) and Methicillin-Resistant Staphylococcus epidermidis (MRSE) Strains Isolated from Patients

Polyphenols have attracted attention in the fight against antibiotic-resistant bacteria, as they show antibacterial action. Considering that polyphenols inhibit F1Fo-ATP synthase (ATP synthase) and that bacteria need a constant energy production to maintain their homeostasis, we evaluated the effect of two flavones, cirsiliol (tri-hy-droxy-6,7-dimethoxyflavone) and quercetin (3,3,4,5,7-pentahydroxyflavone), on energy production and intracellular ATP content in a methicillin-resistant Staphylococcus aureus (MRSA) strain and a methicillin-resistant Staphylococcus epidermidis (MRSE) strain isolated from patients, comparing the results to those obtained by treating the bacteria with oligomycin, a specific ATP synthase Fo moiety inhibitor. Real-time quantitative ATP synthesis and total ATP content of permeabilized Gram-positive bacteria were assayed by luminometry. The results showed that cirsiliol and quercetin inhibited ATP synthase and decreased the intracellular ATP levels in both strains, although the effect was higher in MRSE. In addition, while cirsiliol and quercetin acted immediately after the treatment, oligomycin inhibited ATP synthesis only after 30 min of incubation, suggesting that the different responses may depend on the different permeability of the bacterial wall to the three molecules. Thus, cirsiliol and quercetin could be considered potential additions to antibiotics due to their ability to target ATP synthase, against which bacteria cannot develop resistance.

Didang Tang inhibits intracerebral hemorrhage-induced neuronal injury via ASK1/MKK7/JNK signaling pathway, network pharmacology-based analyses combined with experimental validation

Background

Intracerebral hemorrhage (ICH) is an acute cerebrovascular disease, which is also a principal consideration for disability. Didang tang (DDT) is a classic traditional Chinese medicine formula for treating ICH. However, its pharmacological mechanism of action has not been elucidated.

Materials and methods

The TCMSP and BATMAN-TCM databases were used to collect chemical compounds and predict targets of DDT. Protein targets in ICH were identified by GeneCards, OMIM, and DrugBank databases. DDT compounds-ICH targets and protein-protein interaction (PPI) networks were constructed for topological analysis and hub-targets screening. Further, Key biological processes and signaling pathways were identified by GO and KEGG enrichment analyses. Then, an ICH rat model and a Cobaltous Chloride (CoCl₂)-induced PC12 cells model were established. Cell viability and lactate dehydrogenase (LDH) release were detected using cck8 and LDH kits. Apoptosis levels were detected by TUNEL assessment and flow cytometry. IL-1β levels were detected by ELISA, while key protein expressions were determined by Western blot.

Results

A total of 126 active compounds related to DDT and 3,263 therapeutic targets for ICH were predicted. The functional enrichment of the GO and KEGG pathways combined with literature studies suggested that DDT is most likely to influence MAPK and apoptotic signaling pathways for ICH treatment. In vitro and in vivo experiments have shown that DDT remarkably inhibited apoptosis and increased the expression of Bcl-2, while inhibiting Bax and cleaved-Caspase 3. For other enriched core proteins, DDT suppressed the phosphorylation of Src and the expression of c-Myc and IL-1β, and up-regulated the level of MMP-9. The further results showed that, DDT decreased the phosphorylation of ASK1, MKK7, JNK and c-JUN.

Conclusion

Based on network pharmacology and experimental validation results, our in vivo and in vitro study indicated that ASK1/MKK7/JNK pathway might be the critical target for DDT against ICH.