ABSTRACT
AIM:To study whether homocysteine (Hcy) inhibits the expression of ATP-binding cassette transporter A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1) by microRNA-33 (miRNA-33) signaling, and reduces the efficiency of reverse cholesterol transport (RCT).METHODS:RAW264.7 macrophages were induced by oxidized low-density lipoprotein (ox-LDL) to establish foam cell model.Oil red O staining was used to determine whether the model was established successfully.miRNA-33 mimics and miRNA-33 inhibitor were transfected into the cells by Lipofectamine 2000, and the cells were exposed to Hcy at concentration of 5 mmol/L for 24 h.The intracellular lipid droplets were observed by Oil red O staining.The expression of ABCA1 and ABCG1 at mRNA and protein levels was determined by real-time PCR and Western blot.The cellular cholesterol content was analyzed by HPLC, and effluent rate of cholesterol was detected by the method of liquid scintillation counting.RESULTS:Compared with blank control group, the lipid content in miRNA-33 mimics group was increased, and the expression of ABCA1 and ABCG1 at mRNA and protein levels was decreased (P<0.05).The intracellular cholesterol content was increased gradually (P<0.05) , and the cellular cholesterol efflux rate was gradually decreased (P<0.05) in miRNA-33 mimics group.Compared with blank control group, the testing results in miRNA-33 inhibitor group were the opposition of those in miRNA-33 mimics group (P<0.05).No difference of the above indexes among blank control group, miRNA-33 mimics-NC group and miRNA-33 inhibitor-NC group was observed.CONCLUSION:Hcy inhibits the mRNA and protein expression of ABCA1 and ABCG1 through miRNA-33 signaling, and reduces the efficiency of RCT in RAW264.7 macrophage-derived foam cells.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the risk factors for anorexia in children, and to reduce the prevalence of anorexia in children.</p><p><b>METHODS</b>A questionnaire survey and a case-control study were used to collect the general information of 150 children with anorexia (case group) and 150 normal children (control group). Univariate analysis and multivariate logistic stepwise regression analysis were performed to identify the risk factors for anorexia in children.</p><p><b>RESULTS</b>The results of the univariate analysis showed significant differences between the case and control groups in the age in months when supplementary food were added, feeding pattern, whether they liked meat, vegetables and salty food, whether they often took snacks and beverages, whether they liked to play while eating, and whether their parents asked them to eat food on time (P<0.05). The results of the multivariate logistic regression analysis showed that late addition of supplementary food (OR=5.408), high frequency of taking snacks and/or drinks (OR=11.813), and eating while playing (OR=6.654) were major risk factors for anorexia in children. Liking of meat (OR=0.093) and vegetables (OR=0.272) and eating on time required by parents (OR=0.079) were protective factors against anorexia in children.</p><p><b>CONCLUSIONS</b>Timely addition of supplementary food, a proper diet, and development of children's proper eating and living habits can reduce the incidence of anorexia in children.</p>