Study on the Neuroprotective Effects of Eight Iridoid Components Using Cell Metabolomics.

Iridoid components have been reported to have significant neuroprotective effects. However, it is not yet clear whether the efficacy and mechanisms of iridoid components with similar structures are also similar. This study aimed to compare the neuroprotective effects and mechanisms of eight iridoid components (catalpol (CAT), genipin (GE), geniposide (GEN), geniposidic acid (GPA), aucubin (AU), ajugol (AJU), rehmannioside C (RC), and rehmannioside D (RD)) based on corticosterone (CORT)-induced injury in PC12 cells. PC12 cells were randomly divided into a normal control group (NC), model group (M), positive drug group (FLX), and eight iridoid administration groups. Firstly, PC12 cells were induced with CORT to simulate neuronal injury. Then, the MTT method and flow cytometry were applied to evaluate the protective effects of eight iridoid components on PC12 cell damage. Thirdly, a cell metabolomics study based on ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q/TOF-MS) was performed to explore changes in relevant biomarkers and metabolic pathways following the intervention of administration. The MTT assay and flow cytometry analysis showed that the eight iridoid components can improve cell viability, inhibit cell apoptosis, reduce intracellular ROS levels, and elevate MMP levels. In the PCA score plots, the sample points of the treatment groups showed a trend towards approaching the NC group. Among them, AU, AJU, and RC had a weaker effect. There were 38 metabolites (19 metabolites each in positive and negative ion modes, respectively) identified as potential biomarkers during the experiment, among which 23 metabolites were common biomarkers of the eight iridoid groups. Pathway enrichment analysis revealed that the eight iridoid components regulated the metabolism mainly in relation to D-glutamine and D-glutamate metabolism, arginine biosynthesis, the TCA cycle, purine metabolism, and glutathione metabolism. In conclusion, the eight iridoid components could reverse an imbalanced metabolic state by regulating amino acid neurotransmitters, interfering with amino acid metabolism and energy metabolism, and harmonizing the level of oxidized substances to exhibit neuroprotective effects.

[Metabolomics of interventional effects of Coptidis Rhizoma and its processed products on oral ulcer due to excess heat in rats].

Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q/TOF-MS) was employed to examine the impact of Coptidis Rhizoma(CR) and its processed products on the metabolism in the rat model of oral ulcer due to excess heat and to compare the effectiveness of CR and its three products. Male SD rats were randomly allocated to the sham-operation(Sham), model(M, oral ulcer due to excess heat), CR, wine/Zingiberis Rhizoma Recens/Euodiae Fructus processed CR(wCR/zCR/eCR), and Huanglian Shangqing Tablets(HST) groups. Except the Sham group, the other groups were administrated with Codonopsis Radix-Astragali Radix decoction by gavage for two consecutive weeks. The anal temperature and water consumption of rats were monitored throughout the modeling period of excess heat. Following the completion of the modeling, oral ulcer was modeled with acetic acid. Hematoxylin-eosin(HE) staining was employed to observe the mucosal pathological changes in oral ulcer. A colorimetric assay was employed to determine the serum level of glutathione peroxidase(GSH-Px). Enzyme-linked immunosorbent assay(ELISA) was conducted to determine the levels of tumor necrosis factor-alpha(TNF-α), interleukin-6(IL-6), interleukin-1ß(IL-1ß), superoxide dismutase(SOD), and malondialdehyde(MDA) in the serum. The non-targeted metabolomics analysis based on UPLC-Q/TOF-MS was conducted on the serum samples. Metabolic profiles were then built, and the potential biomarkers were screened by principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA). The Mev software was used to establish a heat map and conduct cluster analysis on the quantitative results of the markers. The online databases including MBRole, KEGG, and MetaboAnalyst were used for pathway enrichment analysis and metabolic network building. The experimental results showed that the modeling led to pathological damage to the oral mucosa, elevated serum levels of TNF-α, IL-6, IL-1ß, and MDA, and lowered levels of SOD and GSH-Px in rats. The drug administration recovered all the indices to varying extents, and wCR exhibited the best performance. Non-targeted metabolomics identified 48 differential metabolites including 27 metabolites in the positive ion mode and 21 metabolites in the negative ion mode. Five enriched pathways were common, including glycerophospholipid metabolism, linoleic acid metabolism, and tyrosine metabolism. Conclusively, CR and its three processed products could alleviate the inflammation and oxidative stress injury in rats suffering from oral ulcers due to excess heat by regulating lipid and amino acid metabolism. Notably, wCR demonstrated the most significant therapeutic effect.

Untargeted serum and gastric metabolomics and network pharmacology analysis reveal the superior efficacy of zingiberis rhizoma recens-/euodiae fructus-processed Coptidis Rhizoma on gastric ulcer rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Zingiberis rhizoma recens-/wine-/euodiae fructus-processed Coptidis Rhizoma (CR, zCR/wCR/eCR) are the commonly used processed products of CR in clinic. After being processed with different excipients, the efficacy of CR will change accordingly. I.e., wCR could resolve excessive heat of the upper energizer, zCR could eliminate gastric heat and harmonize the stomach, eCR could smooth the liver and harmonize the stomach. However, the underlying mechanisms were still unclear. AIM OF THE STUDY: To further verify the differential efficacy of the three processed CR products and compare the mechanisms on gastric ulcer. MATERIAL AND METHODS: First, a GU model, whose onset is closely related to the heat in stomach and the disharmony between liver and stomach, was established, and the therapeutic effects of zCR/wCR/eCR/CR were evaluated by pathologic observation and measurement of cytokine levels. Second, metabolomics analysis and network pharmacology were conducted to reveal the differential intervening mechanism of zCR/eCR on GU. Third, the predicted mechanisms from metabolomics analysis and network pharmacology were validated using western blotting, flow cytometry and immunofluorescence. RESULTS: zCR/wCR/eCR/CR could alleviate the pathologic damage to varying degrees. In metabolomics research, fewer metabolic pathways were enriched in serum samples, and most of them were also present in the results of gastric tissue samples. The gastroprotective, anti-inflammatory, antioxidant, and anti-apoptotic effects of zCR/wCR/eCR/CR might be due to their interference on histidine, arachidonic acid, and glycerophospholipids metabolism. Quantitative results indicated that zCR/eCR had a better therapeutic effect than wCR/CR in treating GU. A comprehensive analysis of metabolomics and network pharmacology revealed that zCR and eCR exerted anti-GU effects via intervening in five core targets, including AKT, TNF, IL6, IL1B and PPARG. In the validation experiment, zCR/eCR could significantly reverse the abnormal expression of proteins related to apoptosis, inflammation, oxidative stress, gastric function, as well as the PI3K/AKT signaling pathways. CONCLUSION: zCR and eCR could offer gastroprotective benefits by resisting inflammation and apoptosis, inhibiting gastric-acid secretion, as well as strengthening gastric mucosal defense and antioxidant capacity. Integrating network pharmacology and metabolomics analysis could reveal the acting mechanism of drugs and promote the development of medications to counteract GU.