An ethanolic extract of Arctium lappa L. leaves ameliorates experimental atherosclerosis by modulating lipid metabolism and inflammatory responses through PI3K/Akt and NF-κB singnaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Atherosclerosis (AS), a lipid-induced inflammatory condition of the arteries, is a primary contributor to atherosclerotic cardiovascular diseases including stroke. Arctium lappa L. leaf (ALL), an edible and medicinal herb in China, has been documented and commonly used for treating stroke since the ancient times. However, the elucidations on its anti-AS effects and molecular mechanism remain insufficient. AIM OF THE STUDY: To investigate the AS-ameliorating effects and the underlying mechanism of action of an ethanolic extract of leaves of Arctium lappa L. (ALLE). MATERIALS AND METHODS: ALLE was reflux extracted using with 70% ethanol. An HPLC method was established to monitor the quality of ALLE. High fat diet (HFD) and vitamin D3-induced experimental AS in rats were used to determine the in vivo effects; and oxidized low-density lipoprotein-induced RAW264.7 macrophage foam cells were used for in vitro assays. Simvatatin was used as positive control. Biochemical assays were implemented to ascertain the secretions of lipids and pro-inflammatory mediators. Haematoxylin-eosin (H&E) and Oil red O stains were employed to assess histopathological alterations and lipid accumulation conditions, respectively. CCK-8 assays were used to measure cytotoxicity. Immunoblotting assay was conducted to measure protein levels. RESULTS: ALLE treatment significantly ameliorated lipid deposition and histological abnormalities of aortas and livers in AS rats; improved the imbalances of serum lipids including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C); notably attenuated serum concentrations of inflammation-associated cytokines/molecules including TNF-α, IL-6, IL-1ß, VCAM-1, ICAM-1and MMP-9. Mechanistic studies demonstrated that ALLE suppressed the phosphorylation/activation of PI3K, Akt and NF-κB in AS rat aortas and in cultured foam cells. Additionally, the PI3K agonist 740Y-P notably reversed the in vitro inhibitory effects of ALLE on lipid deposition, productions of TC, TNF-α and IL-6, and protein levels of molecules of PI3K/Akt and NF-κB singnaling pathways. CONCLUSIONS: ALLE ameliorates HFD- and vitamin D3-induced experimental AS by modulating lipid metabolism and inflammatory responses, and underlying mechanisms involves inhibition of the PI3K/Akt and NF-κB singnaling pathways. The findings of this study provide scientific justifications for the traditional application of ALL in managing atherosclerotic diseases.

Arctium lappa leaves based on network pharmacology and experimental validation attenuate atherosclerosis by targeting the AMPK-mediated PPARG/LXRα pathway.

Arctium lappa (A. lappa) leaves are widely used in various traditional Chinese herbal formulae to ameliorate atherosclerosis (AS) and its complications such as stroke; however, there is no literature reporting the anti-atherosclerotic effect and mechanism of A. lappa leaves thus far. In the present study, we used network pharmacology and molecular docking approaches to examine the protective effect and potential mechanism of A. lappa leaves against AS in vivo and in vitro. From the network pharmacology, PPARG, HMGCR and SREBF2 were identified as the core targets of A. lappa leaves against AS. Further enrichment analyses of GO and KEGG pathways suggested that A. lappa leaves might play an anti-AS role by regulating metabolic processes and PPAR signalling pathways. The results of molecular docking experiment revealed that the major components of A. lappa leaves interacted with cholesterol efflux-regulating core proteins (PPARG, LXRα, ABCA1, and ABCG1), AMPK and SIRT1. Both in vivo and in vitro experimental results demonstrated that treatment with A. lappa leaves significantly lowered TC and LDL-C, increased HDL-C, and reduced cholesterol accumulation in the liver and aorta of the AS rat model and the foam cell model. Importantly, both in vivo and in vitro experimental results demonstrated that A. lappa leaves regulate the activity of the PPARG/LXRα signalling and AMPK/SIRT1 signalling pathways. Moreover, after treatment with the AMPK inhibitor Compound C in vitro, the improvement induced by A. lappa leaves was significantly reversed. In conclusion, A. lappa leaves attenuated AS-induced cholesterol accumulation by targeting the AMPK-mediated PPARG/LXRα pathway and promoting cholesterol efflux.

Protective effect of active components of Eucommia ulmoides leaves on gastric ulcers in rats: Involvement of the PI3K/Akt/NF-κB pathway.

Eucommia ulmoides leaves are widely developed as food and medicines in China and Japan. Its main components have anti-inflammatory properties against gastric ulcers. The purpose of this study was to assess the protective role of an extract derived from the active components of Eucommia ulmoides leaves (EUL 50) against a gastric ulcer and analyze the underlying antiulcer mechanism. The main components of EUL 50 were identified using an ultra-performance liquid chromatography (UPLC) method. Network pharmacology and molecular docking were performed to predict the possible mechanism of action of EUL 50 in the treatment of gastric ulcers. The rats received EUL 50 intragastric administration twice a day for 3 days. Hydrochloric acid/ethanol (HCl/EtOH) was utilized to induce gastric ulcers, followed by histopathological and histochemical evaluation of the ulcer tissues and determination of the main oxidative stress parameters and inflammatory cytokines. The expression of PI3K/Akt/NF-κB pathway-related proteins was measured. Neochlorogenic acid, chlorogenic acid, rutin, and so on were identified as the major components of EUL 50 by UPLC. The prediction results identified the PI3K/Akt/NF-κB signaling pathway as the main possible protective mechanism against gastric ulcers. Furthermore, in a dose-dependent manner, EUL 50 reduced gastric tissue damage. In addition, the high dose of EUL 50 administration resulted in remarkable reductions in the levels of malondialdehyde (MDA), tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and interleukin-1ß (IL-1ß) by 22.64%, 42.61%, 57.78%, and 56.51%, respectively, and suppression of the phosphorylation of Akt, p65, IKKα, and IκBα by 60.87%, 67.65, 74.58%, and 59.57%, respectively, and increased the antioxidant enzyme activity. EUL 50 is rich in flavonoids and organic acids that can act on the PI3K/Akt/NF-κB signaling pathway; as a result, oxidative stress and inflammation are considerably reduced, and gastric ulcers caused by HCl/EtOH are reduced. PRACTICAL APPLICATION: As a medicinal and food substance, Eucommia ulmoides leaves are widely used in the development of health products. EUL 50, a moderately polar part of E. ulmoides leaves, was obtained by extraction and enrichment and was found to have a better protective effect against HCl/EtOH-induced gastric ulcers. This finding can enrich the traditional application of E. ulmoides leaves and provide a basis for their health product development.

Mechanism by which Eucommia ulmoides leaves Regulate Nonalcoholic fatty liver disease based on system pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Eucommia ulmoides (E. ulmoides) leaves are included in the Chinese Pharmacopoeia, and are traditionally used to treat hypertension, obesity, diabetes, and other diseases. Numerous pharmacological studies have shown that E. ulmoides has a good effect on lowering blood lipids and can improve obesity and nonalcoholic fatty liver. AIM: To study the mechanism of E. ulmoides leaves in regulating nonalcoholic fatty liver disease by combining prediction and validation. METHODS: Using network pharmacology, and molecular docking to predict E. ulmoides in regulating the action mechanism and potential active ingredients of nonalcoholic fatty liver, large hole adsorption resin enrichment active sites, in vitro experiments were performed to verify its fat-lowering effect and mechanism. RESULTS: The major components of E. ulmoides leaves exhibited good combination with lipid metabolism-regulating core proteins, particularly flavonoids. EUL 50 significantly reduced lipid accumulation, and increased PPARγ. Compared with the control group, the autophagy level increased after the administration of EUL 50. PPARγ decreased significantly after the addition of chloroquine (CQ, autophagy inhibitor). CONCLUSION: The active ingredients in E. ulmoides leaves regulating nonalcoholic fatty liver disease are mainly flavonoids and phenolics. EUL 50 may play a role in lowering lipids by regulating PPARγ expression through inducing autophagy.