Objective: To study the effects of Apolipoprotein E (ApoE) polymorphism onserum levels of lipids, lipoproteins and apolipoproteins. Methods: Fragments of ApoE gene forthex-on containing codon 112 and 158 polymorphic l...Objective: To study the effects of Apolipoprotein E (ApoE) polymorphism onserum levels of lipids, lipoproteins and apolipoproteins. Methods: Fragments of ApoE gene forthex-on containing codon 112 and 158 polymorphic locus were amplified by PCR, and then digested untilCfo I endonuclease. Genotypes and alleles frequencies of 168 healthy persons in Jiangsu area werecalculated. The effects of ApoE genotypes and alleles on serum lipids, lipoproteins andapolipoproteins variation were analyzed. Results: The effects of ApoE alleles on total cholesterol(TC), law density lipoprotein-cholesterol (LDL-C), ApoB was: along a decreasing gradientε_4>ε_3>ε_2. The effect of ε_4 allele was to increase serum levels of TC, LDL-C and ApoB, andthe ε_2 allele had an effect opposite to that of ε_4 allele. Conclusion: ApoE polymorphism is anindependent genetic factor on individual serum levels of lipids and apolipoproteins.展开更多
The liver is considered the major “control center” for maintenance of whole body cholesterol homeostasis. This organ is the main site for de novo cholesterol synthesis, clears cholesterol-containing chylomicron remn...The liver is considered the major “control center” for maintenance of whole body cholesterol homeostasis. This organ is the main site for de novo cholesterol synthesis, clears cholesterol-containing chylomicron remnants and low density lipoprotein particles from plasma and is the major contributor to high density lipoprotein (HDL; good cholesterol) formation. The liver has a central position in the classical definition of the reverse cholesterol transport pathway by taking up periphery-derived cholesterol from lipoprotein particles followed by conversion into bile acids or its direct secretion into bile for eventual removal via the feces. During the past couple of years, however, an additional important role of the intestine in maintenance of cholesterol homeostasis and regulation of plasma cholesterol levels has become apparent. Firstly, molecular mechanisms of cholesterol absorption have been elucidated and novel pharmacological compounds have been identified that interfere with the process and positively impact plasma cholesterol levels. Secondly, it is now evident that the intestine itself contributes to fecal neutral sterol loss as a cholesterol-secreting organ. Finally, very recent work has unequivocally demonstrated that the intestine contributes significantly to plasma HDL cholesterol levels. Thus, the intestine is a potential target for novel anti-atherosclerotic treatment strategies that, in addition to interference with cholesterol absorption, modulate direct cholesterol excretion and plasma HDL cholesterol levels.展开更多
Objective To verify the regulation of acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT 2), which is associated with cholesterol metabolism, by saturated fatty acids (SFAs). Methods Palmitic acid (PA), the most abun...Objective To verify the regulation of acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT 2), which is associated with cholesterol metabolism, by saturated fatty acids (SFAs). Methods Palmitic acid (PA), the most abundant saturated fatty acid in plasma, and oleic acid (OA), a widely distributed unsaturated fatty acid, were used to treat hepatic cells HepG2, HuH7, and mouse primary hepatocytes. In addition, PA at different concentrations and PA treatment at different durations were applied in HepG2 cells. In in vivo experiment, three-month male C57/BL6 mice were fed with control diet and SFA diet containing hydrogenated coconut oil rich of SFAs. The mRNA level of ACAT2 in those hepatic cells and the mouse livers was detected with real-time polymerase chain reaction (PCR). Results In the three types of hepatic cells treated with PA, that SFA induced significant increase of ACAT2 expression (P<0.01), whereas treatment with OA showed no significant effect. That effect of PA was noticed gradually rising along with the increase of PA concentration and the extension of PA treatment duration (both P<0.05). SFA diet feeding in mice resulted in a short-term and transient increase of ACAT2 expression in vivo, with a peak level appearing in the mice fed with SFA diet for two days (P<0.05). Conclusion SFA may regulate ACAT2 expression in human and mouse hepatic cells and in mouse livers.展开更多
文摘Objective: To study the effects of Apolipoprotein E (ApoE) polymorphism onserum levels of lipids, lipoproteins and apolipoproteins. Methods: Fragments of ApoE gene forthex-on containing codon 112 and 158 polymorphic locus were amplified by PCR, and then digested untilCfo I endonuclease. Genotypes and alleles frequencies of 168 healthy persons in Jiangsu area werecalculated. The effects of ApoE genotypes and alleles on serum lipids, lipoproteins andapolipoproteins variation were analyzed. Results: The effects of ApoE alleles on total cholesterol(TC), law density lipoprotein-cholesterol (LDL-C), ApoB was: along a decreasing gradientε_4>ε_3>ε_2. The effect of ε_4 allele was to increase serum levels of TC, LDL-C and ApoB, andthe ε_2 allele had an effect opposite to that of ε_4 allele. Conclusion: ApoE polymorphism is anindependent genetic factor on individual serum levels of lipids and apolipoproteins.
基金Supported by grant 2001B043 from the Netherlands Heart Foundation
文摘The liver is considered the major “control center” for maintenance of whole body cholesterol homeostasis. This organ is the main site for de novo cholesterol synthesis, clears cholesterol-containing chylomicron remnants and low density lipoprotein particles from plasma and is the major contributor to high density lipoprotein (HDL; good cholesterol) formation. The liver has a central position in the classical definition of the reverse cholesterol transport pathway by taking up periphery-derived cholesterol from lipoprotein particles followed by conversion into bile acids or its direct secretion into bile for eventual removal via the feces. During the past couple of years, however, an additional important role of the intestine in maintenance of cholesterol homeostasis and regulation of plasma cholesterol levels has become apparent. Firstly, molecular mechanisms of cholesterol absorption have been elucidated and novel pharmacological compounds have been identified that interfere with the process and positively impact plasma cholesterol levels. Secondly, it is now evident that the intestine itself contributes to fecal neutral sterol loss as a cholesterol-secreting organ. Finally, very recent work has unequivocally demonstrated that the intestine contributes significantly to plasma HDL cholesterol levels. Thus, the intestine is a potential target for novel anti-atherosclerotic treatment strategies that, in addition to interference with cholesterol absorption, modulate direct cholesterol excretion and plasma HDL cholesterol levels.
基金Supported by National Natural Science Foundation of China (30721063)National High Technology Research and Development Program of China (863 Program) (2006AA02A406)+1 种基金National Basic Research Program of China (973 Program) (2006CB503801)Special Fund of the National Laboratory of China (2060204)
文摘Objective To verify the regulation of acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT 2), which is associated with cholesterol metabolism, by saturated fatty acids (SFAs). Methods Palmitic acid (PA), the most abundant saturated fatty acid in plasma, and oleic acid (OA), a widely distributed unsaturated fatty acid, were used to treat hepatic cells HepG2, HuH7, and mouse primary hepatocytes. In addition, PA at different concentrations and PA treatment at different durations were applied in HepG2 cells. In in vivo experiment, three-month male C57/BL6 mice were fed with control diet and SFA diet containing hydrogenated coconut oil rich of SFAs. The mRNA level of ACAT2 in those hepatic cells and the mouse livers was detected with real-time polymerase chain reaction (PCR). Results In the three types of hepatic cells treated with PA, that SFA induced significant increase of ACAT2 expression (P<0.01), whereas treatment with OA showed no significant effect. That effect of PA was noticed gradually rising along with the increase of PA concentration and the extension of PA treatment duration (both P<0.05). SFA diet feeding in mice resulted in a short-term and transient increase of ACAT2 expression in vivo, with a peak level appearing in the mice fed with SFA diet for two days (P<0.05). Conclusion SFA may regulate ACAT2 expression in human and mouse hepatic cells and in mouse livers.
