Baohuoside I inhibits FXR signaling pathway to interfere with bile acid homeostasis via targeting ER α degradation.

Epimedii folium (EF) is an effective herbal medicine in osteoporosis treatment, but the clinical utilization of EF has been limited due to potential hepatotoxicity. The previous studies identified that baohuoside I (BI), the main active component of EF, was relevant to EF-induced liver injury. However, the mechanisms of BI causing direct injury to hepatocytes remain unclear. Here, we reveal that BI inhibits FXR-mediated signaling pathway via targeting estrogen receptor α (ER α), leading to the accumulation of bile acids (BAs). Targeted bile acid analyses show BI alters the BA composition and distribution, resulting in impaired BA homeostasis. Mechanistically, BI induces FXR-dependent hepatotoxicity at transcriptional level. Additionally, ER α is predicted to bind to the FXR promoter region based on transcription factor binding sites databases and we further demonstrate that ER α positively regulates FXR promoter activity and affects the expression of target genes involved in BA metabolism. Importantly, we discover that ER α and its mediated FXR transcription regulation might be involved in BI-induced liver injury via ligand-dependent ER α degradation. Collectively, our findings indicate that FXR is a newly discovered target gene of ER α mediated BI-induced liver injury, and suggest BI may be responsible for EF-induced liver injury.

Antidiabetic Effects and Mechanisms of Rosemary (Rosmarinus officinalis L.) and its Phenolic Components.

Diabetes mellitus is a chronic endocrine disease result from absolute or relative insulin secretion deficiency, insulin resistance, or both, and has become a major and growing public healthy menace worldwide. Currently, clinical antidiabetic drugs still have some limitations in efficacy and safety such as gastrointestinal side effects, hypoglycemia, or weight gain. Rosmarinus officinalis is an aromatic evergreen shrub used as a food additive and medicine, which has been extensively used to treat hyperglycemia, atherosclerosis, hypertension, and diabetic wounds. A great deal of pharmacological research showed that rosemary extract and its phenolic constituents, especially carnosic acid, rosmarinic acid, and carnosol, could significantly improve diabetes mellitus by regulating glucose metabolism, lipid metabolism, anti-inflammation, and anti-oxidation, exhibiting extremely high research value. Therefore, this review summarizes the pharmacological effects and underlying mechanisms of rosemary extract and its primary phenolic constituents on diabetes and relative complications both in vitro and in vivo studies from 2000 to 2020, to provide some scientific evidence and research ideas for its clinical application.

[Advances in research on hypolipidemic mechanism of phytosterols].

Hyperlipidemia,as one of the severe risk factors of cardiovascular disease,could easily trigger atherosclerosis,coronary heart disease,peripheral vascular disease,pancreatitis,etc.,and could also increase the incidence of type 2 diabetes and fatty liver disease. Improving dyslipidemia could slow down the progression of atherosclerosis and reduce the risk of coronary heart disease. This is of great importance for prevention and treatment of cardiovascular disease. Phytosterols are natural active ingredients in plants. Many researches have shown that phytosterols have significant lipid-lowering activity,which could effectively lower blood cholesterol and triglyceride levels. Foods containing phytosterols have been widely used as therapeutic diets for improving dyslipidemia. In the early years,it was believed that the lipid-lowering effect of phytosterols was achieved by competitively inhibiting the absorption of dietary cholesterol in the intestine since phytosterols had similar chemical structures with cholesterol. In further researches in recent years,more progress has been made in the lipid-lowering mechanisms of phytosterols. In this paper,PubMed and Web of Science were used to review the cholesterol-lowering and triglyceride-lowering mechanisms of phytosterols according to the available data published,so as to use phytosterols more rationally in clinical application to improve hyperlipidemia and other induced diseases.

Rapid discovery of cyclopamine analogs from Fritillaria and Veratrum plants using LC-Q-TOF-MS and LC-QqQ-MS.

Cyclopamine, an inhibitor of the Hedgehog (Hh) signaling pathway, has been paid much attention in treating a wide variety of tumors. However, isolation and purification of cyclopamine analogs from medicinal plants remain challengeable. We herein proposed an efficient strategy using liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-Q-TOF-MS) and liquid chromatography triple-quadrupole mass spectrometry (LC-QqQ-MS) for rapid screening and targeted isolation of cyclopamine analogs in Fritillaria and Veratrum plants. Firstly, fifteen reference compounds were characterized by LC-Q-TOF-MS and their characteristic fragment ions were summarized. Secondly, according to the characteristic fragment ions at m/z 67.1, 84.1, 109.1 and 114.1, rapid chemical screening of plant extracts was carried out by LC-QqQ-MS using precursor ion scan mode and 69 pre-target compounds were screened out. Thirdly, 24 real target compounds were verified by LC-Q-TOF-MS based on relative abundances (over 20%) of characteristic fragment ions. Fourthly, the targeted isolation of Fritillaria ussuriensis bulb and Veratrum dahuricum rhizome afforded a novel cyclopamine analog namely 15ß-hydroxy-23-isopengbeisine B as well as four known ones, whose structures were determined by nuclear magnetic resonance (NMR) analysis. Additionally, these five analogs were evaluated for the inhibitory activity of Hh signaling pathway in NIH/3T3 cell and cytotoxicity in PANC-1 and HepG2 cells. These results indicated that the proposed strategy was reliable for rapid discovery and targeted isolation of important natural products from chemically complex plant matrices.