ABSTRACT
Krüppel-like transcription factor 2 (KLF2) plays a key regulatory role in endothelial inflammation, thrombosis, angiogenesis and macrophage inflammation and polarization, and up-regulation of KLF2 expression has the potential to prevent and treatment atherosclerosis. In this study, trichostatin C (TSC) was obtained from the secondary metabolites of rice fermentation of Streptomyces sp. CPCC 203909 as a KLF2 up-regulator by using a high throughput screening model based on a KLF2 promoter luciferase reporter assay. TSC significantly inhibited the adhesion of tumor necrosis factor-α (TNFα) induced monocytes (THP-1) to human umbilical vein endothelial cells (HUVECs). Western blot results showed that TSC decreased TNFα induced the protein expression increase of vascular cell adhesion molecule-1 (VCAM-1), and thereby inhibited endothelial inflammation. The results of histone deacetylase (HDAC) overexpression and molecular docking experiments showed that TSC upregulated the expression of KLF2 by inhibiting subtypes of HDAC 4/5/7. In conclusion, this study suggests that TSC up-regulates the expression of KLF2 through inhibiting HDAC 4/5/7 and thus inhibits TNFα induced endothelial inflammation, and it has the potential to prevent and treat atherosclerosis.
ABSTRACT
Osteoprotegerin (OPG), secreted by osteoblasts, is a marker of bone turnover. OPG can inhibit osteoclastic differentiation by binding receptor activator of nuclear factor-κB ligand (RANKL). In this study, we found that rutaecarpine (RUT) had the up-regulating OPG activity, and it could significantly increase OPG protein levels in both mouse embryonic osteogenic precursor MC3T3-E1 and human osteosarcoma U-2OS cells. Osteoblastogenic differentiation calcified nodules staining results showed that RUT significantly promoted the osteogenic differentiation of MC3T3-E1 cells. Osteoclastic differentiation tartrate resistant acid phosphatase (TRAP) staining results showed that RUT obviously inhibited the osteoclast differentiation of mouse macrophages RAW264.7 induced by RANKL. In vivo studies showed that low-dose RUT group (5 mg·kg-1·day-1) and high-dose RUT group (45 mg·kg-1·day-1) treatments for 3 months significantly increased bone density in ovariectomized (OVX) rats; calcein double labeling experiment and toluidine blue staining results indicated that low-dose RUT group promoted bone formation and decreased bone loss in vivo; immunohistochemistry results showed that low-dose RUT group increased the expression of OPG in rat femur. All animal procedures were performed in accordance with the regulations of the Institutional Animal Care and Use Committee of Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences. In summary, this study demonstrated that RUT could up-regulate OPG expression and had promoting osteoblastic differentiation and inhibiting osteoclastic differentiation effects in vitro and in vivo.
ABSTRACT
The purpose of this research is to study the anti-atherosclerotic effects and mechanisms of berberine (BBR) in high fat diet (HFD) fed ApoE-/- mice, and then to lay a solid foundation of the clinical studies of BBR treatment. The hyperlipidemic ApoE-/- mice model was established by feeding HFD for 12 weeks. Mice were randomly divided into control group (chow diet), model group, BBR group (BBR-L: 50 mg·kg-1, BBR-H: 150 mg·kg-1) and atorvastatin (5 mg·kg-1) group. Mice were intragastric administration with BBR in 0.5% sodium salt of caboxy methyl cellulose. After 12 weeks, enface aortas were stained with oil red O, and the lesions area were analyzed by Image J software. The inflammatory factor levels were detected by suspension microarray kits. Liver total cholesterol (TC), triglyceride (TG) and free fatty acids (FFA) were determined by commercial kits. Western blot was performed to examine the inflammatory pathway related and cholesterol and lipid transport related proteins' expression. All animal experiments were performed in accordance with the Regulation on the Administration of Laboratory Animals of Institute of Medicinal Biotechnology. After 12 weeks treatment, compared with model group, BBR treatment significantly reduced the lesions area of en face aortas and obviously inhibited serum proinflammatory factors such as IL-1β and IL-6 compared with model group. In addition, BBR treatment obviously reduced liver TC, TG and FFA levels compared with model group. Furthermore, mechanic study showed that BBR significantly inhibited MAPKs and NF-κB pathways, and increased cholesterol and lipid regulated proteins expression such as p-AMPK, LDLR, ABCA1 and SR-BI. In conclusion, BBR can obviously reduce enface aortas lesions in ApoE-/- mice, which is related to inhibit inflammation and liver cholesterol and lipid accumulation.