Marein reduces lipid levels via modulating the PI3K/AKT/mTOR pathway to induce lipophagy.

ETHNOPHARMACOLOGICAL RELEVANCE: The capitulum of Coreopsis tinctoria Nutt. (CT, Xue-Ju in Chinese) is a precious medicine in Xinjiang Uygur Autonomous region of China. The Coreopsis tinctoria Nutt. is used to prevent and treat dyslipidemia, coronary heart disease, etc. Recent studies have shown that its extract has a pharmacological effect on hyperlipidemia and hyperglycemia. AIM OF THE STUDY: The study aimed to systematically evaluate the lipid-lowering activity of CT through a mice model of hyperlipidemia and a human hepatoma G2 (HepG2) cells model of lipid accumulation, and to investigate its main active components and mechanism. MATERIALS AND METHODS: Biochemical analysis of blood/liver lipids and liver histopathology were used to evaluate the effect of the aqueous extract of Coreopsis tinctoria Nutt. (AECT) on hyperlipidemia mice. High-performance liquid chromatography (HPLC) analysis was used to identify the main components in the AECT. Oil red O staining, immunofluorescence, western blotting, and determination of the total cholesterol (TC), total triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were used to further study the effect and potential mechanism of the AECT main components on sodium oleate-induced lipid accumulation in HepG2 cells. RESULTS: We confirmed the lipid-lowering activity of the aqueous extract and further identified flavonoids as its main components. Among them, five Coreopsis tinctoria Nutt. flavonoids mixture (FM) significantly reduced lipid droplet area, lipid content, TC, TG, and LDL-C levels, and elevated HDL-C levels in HepG2 cells induced by sodium oleate. Furthermore, they increased lipophagy in HepG2 lipid-accumulating cells, while decreasing the ratio of p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR. Most importantly, marein may be a key component. CONCLUSIONS: Our study demonstrated that AECT, with flavonoids as the main component, can improve diet-induced hyperlipidemia in obese mice. Among the main five flavonoids, marein plays a key role in promoting lipophagy by regulating the PI3K/AKT/mTOR pathway, resulting in a lipid-lowering effect.

[Precise application of Beichaihu and Nanchaihu in classical formulas].

To maintain the precision and stability of the efficacy of classical formulas, this study compared the origins and specifications of Bupleuri Radix and revealed the precise application regularity of Bupleurum chinense(Beichaihu) and Bupleurum scorzonerifolium(Nanchaihu) in classical formulas. The efficacy and indications of formulas with Bupleuri Radix as the sovereign drug in the Treatise on Cold Damage and Miscellaneous Diseases(Shang Han Za Bing Lun) were investigated. The difference in the efficacy of Bupleuri Radix as well as the differences in the chemical composition, and liver-protecting and lipid-lowering effects of the decoctions of Beichaihu and Nanchaihu were analyzed with LC-MS technology based on the CCl_4-induced liver injury model in mice and sodium oleate-induced HepG2 hyperlipidemia cell model. The results showed that seven classical formulas with Bupleuri Radix as the sovereign drug in the Treatise on Cold Damage and Miscellaneous Diseases were mainly used in the treatment of digestive, metabolic, immune, circulatory, and other diseases. Bupleuri Radix mainly played the functions of protecting the liver, benefiting the gallbladder, and lowering the lipid, and had different focuses in different formulas. There were 14 differential components in the decoctions of Beichaihu and Nanchaihu, and the chemical structures of 11 components were identified, including 10 saponins and one flavonoid. The results of the liver-protecting efficacy experiment showed that compared with the Nanchaihu decoction, Beichaihu decoction could reduce the serum aspartate aminotransferase(AST) activity in liver injury model mice(P<0.01). The results of the lipid-lowering efficacy experiment proved that Beichaihu and Nanchaihu decoctions both showed highly significant differences in lowering the total cholesterol(TC) and triglyceride(TG) content in HepG2 cells(P<0.01), and Nanchaihu decoction was superior to Beichaihu decoction in lowering the lipid. The results of this study preliminarily proved that there were differences in chemical composition, and liver-protecting and lipid-lowering effects of Beichaihu and Nanchaihu decoctions, indicating that it was necessary to determine the precise origin of Bupleuri Radix in the clinical formulation of traditional Chinese medicine. The study provides a scientific basis for both precise clinical medication and purpose-based accurate quality evaluation of traditional Chinese medicine in clinical application.

The antiviral mechanism of the crude extract from the flowers of Trollius chinensis based on TLR 3 signaling pathway.

The effects of crude extract from the flowers of Trollius chinensis on expressions of mRNA and proteins related to vital genes (TLR 3, TBK 1, IRF 3 and IFN ß) in TLR 3 signaling pathway were investigated in the presence/absence of Polyinosinic acid-polycytidylic acid (PolyI: C) to ascertain the antiviral mechanism of these flowers. Real-time PCR and western blot were applied to determine the expressions of mRNA and proteins, respectively, and immunofluorescence assay was employed to study the effect on IRF 3 distribution between nuclei and cytoplasma. In the absence of PolyI:C, the crude extract reduced the mRNA expression of TLR 3, IRF 3 and IFN ß and the protein expression of TLR 3, and increased the protein expression of IRF 3 and the distribution of IRF 3 in nuclei. In the presence of PolyI:C, the extract reduced the mRNA and protein expressions of TLR 3 and the mRNA expression of IFN ß, meanwhile inhibited the translocation of IRF 3 into nuclei. The antiviral mechanism of the crude extract from the flowers of T. chinensis is to protect the host from inflammatory damage through intervening the TLR 3 signaling pathway and reducing the secretion of inflammatory factors.

Anti-inflammatory effect of the compounds from the flowers of Trollius chinensis.

In order to investigate the anti-inflammatory activity of flavonoids, phenolic acids, and alkaloids from the flowers of Trollius chinensis, some representative compounds, namely, orientin, 2"-O-ß-L-galactopyranosylorientin, vitexin, quercetin, isoquercetin, luteolin, veratric acid, proglobeflowery acid, trollioside, and trolline were selected to study their inhibitory effects against LPS-induced NO, IL-6, and TNF-ß release in RAW264.7 cells. At the higher concentration, both phenolic acids and flavonoids inhibited the production of NO, whereas only phenolic acids showed this effect at the lower concentration. Although trolline had stronger cytotoxicity, it exhibited a potential effect of decreasing NO production induced by LPS in the non-toxic concentration range. In addition, all tested compounds decreased the production of IL-6 and TNF-a by almost 50% at both the higher and lower concentrations. It is concluded that the anti-inflammatory activity of the phenolic acids is stronger than that of the flavonoids.