We studied the effects of alfalfa saponin extract（ASE） on low density lipoprotein receptor（Ldlr）, liver X receptor α（LXRα）, and farnesoid X receptor（FXR） in normal and hyperlipidemic Buffalo rat liver（BRL）...We studied the effects of alfalfa saponin extract（ASE） on low density lipoprotein receptor（Ldlr）, liver X receptor α（LXRα）, and farnesoid X receptor（FXR） in normal and hyperlipidemic Buffalo rat liver（BRL） cells. Normal and hyperlipidemic BRL cells were divided into eight groups： normal, or normal cells treated with 50, 100, and 150 mg/L ASE, hyperlipidemic, or hyperlipidemic cells treated with 50, 100, and 150 mg/L ASE. After treatment for 24 h, Ldlr, LXRα, and FXR m RNA expression levels were measured by quantitative real-time polymerase chain reaction（q RT-PCR）. Data showed that m RNA expression of Ldlr in normal BRL cells was significantly up-regulated by ASE treatment and m RNA expressions of LXRα and FXR were significantly down-regulated both in normal and hyperlipidemic BRL cells after ASE treatment. Thus, ASE might ameliorate hepatic steatosis by regulating genes involved in cholesterol metabolism, including up-regulation of Ldlr as well as down-regulation of LXRα and FXR.展开更多
The potential applications of superparamagnetic iron oxide nanoparticles （SPIONs） in several nanomedical fields have attract- ed intense interest based on the cell-nano interaction. However, the mechanisms underlyin...The potential applications of superparamagnetic iron oxide nanoparticles （SPIONs） in several nanomedical fields have attract- ed intense interest based on the cell-nano interaction. However, the mechanisms underlying cell uptake, the intracellular trail, final fate and the biological effects of SPIONs have not yet been clearly elucidated. Here, we showed that multiple endocytic pathways were involved in the internalization process of SPIONs in the RAW264.7 macrophage. The internalized SPIONs were biocompatible and used three different metabolic pathways： The SPIONs were distributed to daughter cells during mito- sis; they were degraded in the lysosome and free iron was released into the intracellular iron metabolic pool; and, the intact SPIONs were potentially exocytosed out of the cells. The internalized SPIONs did not induce cell damage hut affected iron metabolism, inducing the upregulation of ferritin light chain at both the mRNA and protein levels and ferroportin 1 at the mRNA level. These results may contribute to the development of nanobiology and to the safe use of SPIONs in medicine when administered as a contrast medium or a drug delivery tool.展开更多
基金Project supported by the National Natural Science Foundation of China(No.31301983)the Earmarked Fund for Modern Agro-industry Technology Research System of China(No.CARS-35)
文摘We studied the effects of alfalfa saponin extract（ASE） on low density lipoprotein receptor（Ldlr）, liver X receptor α（LXRα）, and farnesoid X receptor（FXR） in normal and hyperlipidemic Buffalo rat liver（BRL） cells. Normal and hyperlipidemic BRL cells were divided into eight groups： normal, or normal cells treated with 50, 100, and 150 mg/L ASE, hyperlipidemic, or hyperlipidemic cells treated with 50, 100, and 150 mg/L ASE. After treatment for 24 h, Ldlr, LXRα, and FXR m RNA expression levels were measured by quantitative real-time polymerase chain reaction（q RT-PCR）. Data showed that m RNA expression of Ldlr in normal BRL cells was significantly up-regulated by ASE treatment and m RNA expressions of LXRα and FXR were significantly down-regulated both in normal and hyperlipidemic BRL cells after ASE treatment. Thus, ASE might ameliorate hepatic steatosis by regulating genes involved in cholesterol metabolism, including up-regulation of Ldlr as well as down-regulation of LXRα and FXR.
基金supported by the National Basic Research Program of China,Ministry of Science and Technology of China (Grant Nos. 2006CB933202 and 2011CB933504) the National High Technology Research and Development Program of China (Grant No. 2008AA02Z425)a grant from the National Natural Science Foundation of China (Grant No.81071072)
文摘The potential applications of superparamagnetic iron oxide nanoparticles （SPIONs） in several nanomedical fields have attract- ed intense interest based on the cell-nano interaction. However, the mechanisms underlying cell uptake, the intracellular trail, final fate and the biological effects of SPIONs have not yet been clearly elucidated. Here, we showed that multiple endocytic pathways were involved in the internalization process of SPIONs in the RAW264.7 macrophage. The internalized SPIONs were biocompatible and used three different metabolic pathways： The SPIONs were distributed to daughter cells during mito- sis; they were degraded in the lysosome and free iron was released into the intracellular iron metabolic pool; and, the intact SPIONs were potentially exocytosed out of the cells. The internalized SPIONs did not induce cell damage hut affected iron metabolism, inducing the upregulation of ferritin light chain at both the mRNA and protein levels and ferroportin 1 at the mRNA level. These results may contribute to the development of nanobiology and to the safe use of SPIONs in medicine when administered as a contrast medium or a drug delivery tool.
