Endothelial-mesenchymal transition (EndMT) disrupts vascular endothelial integrity and induces atherosclerosis. Active integrin β1 plays a pivotal role in promoting EndMT by facilitating TGFβ/Smad signaling in endothelial cells. Here, we report a novel anthraquinone compound, Kanglexin (KLX), which prevented EndMT and atherosclerosis by activating MAP4K4 and suppressing integrin β1/TGFβ signaling. First, KLX effectively counteracted the EndMT phenotype and mitigated the dysregulation of endothelial and mesenchymal markers induced by TGFβ1. Second, KLX suppressed TGFβ/Smad signaling by inactivating integrin β1 and inhibiting the polymerization of TGFβR1/2. The underlying mechanism involved the activation of FGFR1 by KLX, resulting in the phosphorylation of MAP4K4 and Moesin, which led to integrin β1 inactivation by displacing Talin from its β-tail. Oral administration of KLX effectively stimulated endothelial FGFR1 and inhibited integrin β1, thereby preventing vascular EndMT and attenuating plaque formation and progression in the aorta of atherosclerotic Apoe^-/- mice. Notably, KLX (20 mg/kg) exhibited superior efficacy compared with atorvastatin, a clinically approved lipid-regulating drug. In conclusion, KLX exhibited potential in ameliorating EndMT and retarding the formation and progression of atherosclerosis through direct activation of FGFR1. Therefore, KLX is a promising candidate for the treatment of atherosclerosis to mitigate vascular endothelial injury.
Animals ; Atherosclerosis/prevention & control* ; Mice ; Receptor, Fibroblast Growth Factor, Type 1/metabolism* ; Signal Transduction/drug effects* ; Anthraquinones/pharmacology* ; Humans ; Integrin beta1/metabolism* ; Epithelial-Mesenchymal Transition/drug effects* ; Male ; Transforming Growth Factor beta/metabolism* ; Disease Models, Animal ; Mice, Inbred C57BL ; Human Umbilical Vein Endothelial Cells/drug effects*

Objective To establish a rapid high performance liquid chromatography(HPLC)method for simultaneous determination of the concentration of total,free and reduced homocysteine (Hcy),glutathione(GSH),cysteine (Cys)and cys-teinylglycine (CysGly). Methods HPLC fluorescence detection method was established under the below conditions. The axci-tation and emission wavelengths was 330 nm and 380 nm respectively;the separation of thiols was achieved by using a C-18 column and the column temperature was 25 ℃;the mobile phase was gradient eluted with the three carboxyl ethyl phosphine (TCEP)as reducing agent and N-1- phenyl maleimide (NPM)as derivatization agent. The HPLC fluorescence detection meth-od was used to measure the thiol concentration in plasma of uraemia patients and healthy people. Results The linear range of total and free Hcy,GSH,Cys and CysGly were 1. 0 - 120. 0,2. 0 - 80. 0,10. 0 - 1500. 0 and 3. 0 - 240. 0 μmol·L - 1 respec-tively;the linear range of reduced Hcy,GSH,Cys and CysGly was 1. 25 - 50. 00,0. 10 - 8. 00,1. 25 - 50. 00 and 0. 01 -4. 00 μmol·L - 1 respectively. The intra-and inter-day ralative standard deviation were less than 5％;the recovery of this meth-od was 80. 1％ - 111. 7％ . The newly established HPLC fluorescence detection method was successfully applied to determine the total,free and reduced concentration of GSH,Cys,Hcy and CysGly in 34 uraemia patients and 32 healthy people. Conclu-sion A new HPLC fluorescence detection method for the determination of Hcy,GSH,Cys,and CysGly in plasma is developed and this method is accurate and reliable.