ABSTRACT
Our previous studies uncovered the glucose-lowering properties of snow chrysanthemum tea, however, the active ingredients and underlying mechanisms were yet to be uncovered. Flavonoids are the most active and abundant components in snow chrysanthemum tea. In this study, we treated leptin-deficient diabetic ob/ob or high-fat diet (HFD)-induced C57BL/6 J obese mice with or without total flavonoids of snow chrysanthemum (TFSC) for 14 weeks. Results indicated that TFSC ameliorated dyslipidemia and fatty liver, thereby reducing hyperlipidemia. Further mechanism experiments, including RNA-seq and experimental validation, revealed TFSC improved glycolipid metabolism primarily by activating the AMPK/Sirt1/PPARγ pathway. Additionally, by integrating UPLC, network pharmacology, transcriptomics, and experimental validation, we identified two novel hypoglycemic compounds, sulfuretin and leptosidin, in TFSC. Treatment with 12.5 µmol/L sulfuretin obviously stimulated cellular glucose consumption, and sulfuretin (3.125, 6.25 and 12.5 µmol/L) significantly mitigated glucose uptake damage and reliably facilitated glucose consumption in insulin-resistant HepG2 cells. Remarkably, sulfuretin interacted with the ligand-binding pocket of PPARγ via three hydrogen bond interactions with the residues LYS-367, GLN-286 and TYR-477. Furthermore, a concentration of 12.5 µmol/L sulfuretin effectively upregulated the expression of PPARγ, exhibiting a comparable potency to a renowned PPARγ agonist at 20 µmol/L. Taken together, our findings have identified two new hypoglycemic compounds and revealed their mechanisms, which significantly expands people's understanding of the active components in snow chrysanthemum that have hypoglycemic effects.
Subject(s)
Chrysanthemum , Hypoglycemic Agents , Mice , Animals , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Molecular Docking Simulation , Chrysanthemum/chemistry , PPAR gamma/genetics , PPAR gamma/metabolism , Network Pharmacology , Transcriptome , Mice, Inbred C57BL , Glucose , Flavonoids/pharmacology , TeaABSTRACT
Mulberry (Morus alba L.) leaves have long been considered beneficial in traditional Chinese medicine to treat infectious and internal diseases. Recently studies have discovered that the mulberry leaf's total flavonoids (MLF) display excellent hypoglycemia properties. However, the active ingredients and their molecular mechanisms are still uncharacterized. In this study, we explored the hypoglycemic effects of MLF and mulberry leaf polysaccharides (MLP) on ob/ob mice, an animal model of type 2 diabetes mellitus (T2DM), compared with Ramulus Mori (Sangzhi) alkaloid (RMA). Network pharmacology was employed to identify the potential available targets and active compounds of MLF and RMA against hyperglycemia. Molecular docking, an insulin-resistant cell model and qPCR were employed to verify the antidiabetic activity of the critical compounds and the gene expression profiles of the top molecular targets. Here, the results showed that MLF and MLP improved glucose uptake in insulin-resistant hepatocytes. MLF, MLP and RMA alleviated insulin resistance and glucose intolerance in ob/ob mice. Unlike MLF and MLP, RMA administration did not influence the accumulation of intrahepatic lipids. Network pharmacology analysis revealed that morusin, kuwanon C and morusyunnansin L are the main active compounds of MLF and that they amend insulin resistance and glycemia via the PI3K- Akt signaling pathway, lipid and atherosclerosis pathways, and the AGE-RAGE signaling pathway. Moreover, 1-deoxynojirimycin (DNJ), fagomine (FA), and N-methyl-1-deoxynojirimycin are the primary active ingredients of RMA and target carbohydrate metabolism and regulate alpha-glucosidase activity to produce a potent anti-diabetic effect. The molecular docking results indicated that morusin, kuwanon C and morusyunnansin L are the critical bioactive compounds of MLF. They had high affinities with the key targets adenosine A1 receptor (ADORA1), AKT serine/threonine kinase 1 (AKT1), peroxisome proliferator-activated receptor gamma (PPARγ), and glycogen synthase kinase 3 beta (GSK3ß), which play crucial roles in the MLF-mediated glucose-lowering effect. Additionally, morusin plays a role in amending insulin resistance of hepatocytes by repressing the expression of the ADORA1 and PPARG genes. Our results shed light on the mechanism behind the glucose-lowering effects of MLF, suggesting that morusin, kuwanon C, and morusyunnansin L might be promising drug leads for the management of T2DM.
ABSTRACT
BACKGROUND: An accurate assessment of the severity and prognosis of sepsis, especially septic shock, is vital for the tailored treatment of this condition. miRNA participates in the inflammatory response and cell apoptosis and regulates inflammation-related signaling pathways. Immune disorders often accompany sepsis. Since serum miRNA expression is superior to traditional biological markers in terms of sensitivity and specificity, its role in the assessment of sepsis has increasingly been recognized. METHODS: Serum miRNAs were extracted from septic patients and healthy individuals by using the ultracentrifugation method. The differential expressions of miRNAs in the serum samples were detected by high-throughput sequencing technology. The differentially expressed miRNAs between the two groups were analyzed by bioinformatics. The quantitative polymerase chain reaction real-time polymerase chain reaction (qRT-PCR) was used to amplify the sample size to verify the results and to screen the highly-expressed miR206 in septic patients. Subsequently, serum samples were collected from 63 septic patients, and 30 patients with septic shock and qRT-PCR were performed to analyze the expression of miR-206. These 93 patients were divided into the miR-206 low-expression group and miR-206 high-expression group according to miR206 expression level. The potential correlations between the miR-206 expression and the clinical data were analyzed by using SPSS 25.0. RESULTS: Serum miRNA expression significantly differed between septic patients and healthy individuals. High-throughput sequencing results showed that, compared with those in healthy individuals, 29 miRNA molecules were down-regulated, and 25 molecules were up-regulated in the serum samples of septic patients. qRT-PCR identified the significantly up-regulated miR-206 in septic patients. qRT-PCR also showed significantly higher miR-206 expression levels in patients with septic shock than in septic patients. Furthermore, we observed a significantly longer prothrombin time and activated partial thromboplastin time, and significantly higher SOFA score, APACHE-II score, and in-hospital mortality rate. miR-206 was positively correlated with SOFA sore and APACHE-II score. CONCLUSIONS: Serum miR-206 expression is positively correlated with the severity and prognosis of sepsis. Thus, it may be a potential biomarker for assessing the severity and prognosis of sepsis, although the specific mechanism warrants further investigations.