ABSTRACT
OBJECTIVE Pulmonary arterial hypertension (PAH) is a malignant pulmonary vascular disease lacking efficacy therapeutics. Therefore, it urgently needs to develop safe and effective drugs for PAH treatment. Osthole derived from Cnidium monnieri (L.) Cusson (Shechuangzi) or Angelica pubescens Maxim (Duhuo) has the capacity to alleviate PAH by decreasing pulmonary arterial pressure and alleviating pulmonary vascular remodeling in rats, which is a candi?date drug for the prevention of PAH, but the underlying modulatory mechanism is still unclear. Our study aims at investi?gating the metabolic modulatory mechanism of osthole against PAH employing functional metabolomics strategy. METH?ODS PAH model rats were successfully established with MCT, following osthole administration, then functional metabo?lomics based on untargeted metabolomics assay, targeted lipidomics analysis, qRT-PCR, Western blotting and ELISA were performed to investigate the modulatory mechanism of osthole against pulmonary arterial pressure and pulmonary vascular remodeling in PAH. RESULTS Untargeted metabolomics results found that sphingosine 1-phosphate (S1P) was the differential metabolites characterized PAH and reversed by osthole treatment. S1P is a crucial sphingolipid metabolite catalyzed by sphingosine kinases1 (Sphk1) and functions as promoting PASMCs proliferation contributing to pulmonary vascular remodeling and pulmonary arterial pressure increase. We revealed that osthole reversed high level of S1P by modulating metabolic enzyme Sphk1 via inactivating microRNA-21-PI3K/Akt/mTOR signal pathway to decrease pulmonary arterial pressure in rats with PAH. Then, targeted phospholipid metabolomics results uncovered that decadienyl-L-carnitine (C10:2) was the differential metabolite characterized PAH and corrected by osthole treatment in rat with PAH. C10:2 is the intermediate metabolite of fatty acid oxidation (FAO), and C10:2 accumulation indicated mitochondrial dysfunction and FAO increase. CONCLUSION Osthole could block lipid metabolic reprogramming through functional modulating the expression of fatty acid translocase, fatty acid synthase, phospholipase A2, carnitine palmitoyltransferase 1A to inhibit C10:2, thus to improve mitochondrial dysfunction and inhibit utilizing lipid to biosyn?thesize necessary essence for pulmonary artery smooth muscle cells (PASMCs) proliferation. Moreover, we delineated that C10:2 and metabolic reprogramming enzymes were modulated by miRNA-22-3p which was involved in PASMCs proliferation and pulmonary vascular remodeling. Therefore, osthole inhibited miRNA-22-3p mediated lipid metabolic reprogramming to ameliorate pulmonary vascular remodeling.
ABSTRACT
Due to potent bactericidal activity and low rate of drug-resistance, daptomycin is recognized as first line antibiotic to treat serious infections caused by drug-resistant Gram-positive pathogens. However, the incidence of daptomycin resistance is increasing due to its widespread application. Alteration of cell wall homeostasis and membrane phospholipid metabolism is involved in daptomycin resistance. The unique mode of action underlying daptomycin resistance in important pathogens, including Staphylococcus aureus and Enterococci, is presented in this paper.