The Relationship Between Human Blood Lipid Profiles And Single Nucleotide Polymorphisms Of LIPC Gene:A Meta-analysis And MiRNA-152 Regulate The Lesions Of Atherosclerosis In Mice And Its Mechanism

Part 1 The relationship between human blood lipid profiles andsingle nucleotide polymorphisms of LIPC gene:A Meta-analysisObjective:Hepatic lipase(LIPC)is a key enzyme in lipoprotein metabolism.In the remodeling of low-density lipoprotein(LDL)and high-density lipoprotein(HDL)particles and residual lipoprotein catabolism,hepatic lipase play a key role.It is associated with many diseases such as coronary heart disease,dyslipidemia,and atherosclerosis.Based on the literature on the effects of two single nucleotide(rs1800588,rs2070895)polymorphisms(SNPs)in the promoter region of hepatic lipase on human blood lipid levels,we performed integrated analysis of the data on the relationship between single nucleotide polymorphisms in hepatic lipase gene and lipid levels in different subspecies in published literature,meta-analysis of blood lipid data of different subpopulations,and investigated the effect of single nucleotide polymorphism of hepatic lipase promoter on human blood lipid levels.Methods:A systematic search of literature in multiple databases was performed,including Wanfang Database,China Knowledge Network,China Biomedical Literature Database.PubMed,Medline.Web of Science,Embase,The Cochrane Library(Cochrane Database of Systematic Reviews)and The Cochrane Central Register of Controlled Trials(CENTRAL).The search time limit is to build the database until October 2017,and potentially relevant articles were selected.Two researchers independently screened the literature and assessed the quality of the literature.The disagreements that emerged during this process were discussed in depth by two authors and were submitted to other authors or correspondence authors for further determination,ultimately determining the research literature that could be included in this meta-analysis.The quality of the literature was evaluated using the NOS scale.The statistical software stata 12.0 was used for meta-analysis.Weighted mean difference(WMD)and 95%confidence interval(CI)explored the relationship between single nucleotide polymorphisms of hepatic lipase promoter and changes in human blood lipid levels using a random effects model.Sensitivity analysis was used to investigate whether the results were stable and Begg rank correlation method was used to evaluate publication bias.Results:A total of 1552 papers were found after a reasonable search in the Internet database,and 127 papers reported different types of SNP in LIPC.Among them,most of the studies analyzed the SNPs(rs 1800588 and rs2070895)in LIPC.Screening and inclusion criteria were developed on screening and retention of the literature.After preliminary screening of all the literature,the remaining 87 articles included the detection of lipid profiles in each LIPC gene polymorphism.Among them,17 articles included 24,946 participants with G-250A,and 72 articles included 76,757 participants with C-514T(-480T).In this study,the participants included in the selected articles were divided into AA+AG/GG,GG/GA/AA,TT+TC/CC,CC/CT/TT based on their initial patient grouping.Further meta-analysis was performed on each of the two genotypes in each group.1.Difference assessment of G-250A blood lipid levels:Plasma HDL-C levels in subjects with AA genotype were significantly higher than those with GG genotype.For other genotypes,plasma HDL-C levels in subjects with all mutant genotypes were higher than those with wild types.The mean plasma TC level in subjects with AA genotype was higher than GG genotype.The mean plasma TG level was higher in carrying A than non-carriers.2.Difference assessment of C-514T blood lipid levels:Plasma HDL-C levels in subjects s with mutant TT were higher than those with CC genotype.Both TC and TG levels in subjects s with TT were higher than those with CC genotype.3.Gender subgroup analysis:Subjects with C-514T had significantly elevated HDL-C levels in men in all of the mutant genotype subgroups.4.Ethnic subgroup analysis:In the G-250A subjects,the HDL-C levels were significantly higher in whites of all mutant genotype subgroups;For C-514T subjects,white TCs in the CT/CC mutant genotype subgroup and TG levels were significantly higher.Conclusions:Through meta-analysis,we found:Two site mutations in LIPC SNPs(C-514T,G-250A)have an effect on the level of HDL-C in humans.Two loci polymorphism of C-514T and G-250A in LIPC may be associated with the incidence of primary hyperlipidemia.Part 2 miRNA-152 regulates the lesions of atherosclerosis in miceand its mechanismBackgrounds:Atherosclerosis(AS)is the main pathological basis for the development of cardiovascular events,and its pathogenesis is still unclear.Recent research generally considers AS to be a chronic vascular inflammatory disease[1].miR-152 is down-regulated in serum samples from AS patients compared to normal controls.It indicates that miR-152 plays a role in the formation of atherosclerosis[2].However,the mechanism by which miR-152 plays a role in the However,miR-152 in the macrophage inflammatory response function remains to be further explored.Kriippel-like factor(KLF)is a kind of transcrition factor with zinc-containing finger structure in eukaryotes,which is important for promoting growth gene family and suppressing differentiation gene family.Its function is mainly involved in regulating cell development,differentiation,proliferation and eventual apoptosis.At present,KLF5 plays a role in early embryonic development,oncogenesis and other physiological and pathological processes,and is expressed in smooth muscle,endothelium and epithelium,especially in vascular remodeling.Bioinformatic research shows that KLF5 is a direct target of miR-152.The typical Wnt/?-catenin signaling pathway(Canonical Wnt/?-catenin pathway)activates the expression of target genes in the nucleus and plays an important role in the differentiation of multicellular organisms[3,4].Recently,there is ample evidence that p-catenin is involved in the pathogenesis of AS[5,6].When the Wnt/?-catenin signaling pathway is aberrantly activated,it can cause abnormal expression of?-catenin,and subsequently leads to abnormal expression of downstream genes,which causes abnormal proliferation and differentiation of cells,eventually leading to disease.Therefore,based on this,we hypothesized that miR-152 may affect the expression of KLF5 by targeting KLF5,affecting apoptosis and inflammatory response,and ultimately affect the development of AS,which may involve ?-catenin signaling pathway.Through this study,we hope to elucidate the possible role and mechanism of miR-152/KLF5 in the development of atherosclerosis to provide the possibility of using miR-152/KLF5 as a therapeutic target for AS in the future.Objectives:To explore the mechanism by which miR-152 regulates the atherosclerosis(AS)through regulation of(3-catenin signaling pathway by KLF5.Methods:First,AS model mice were constructed and compared with control mice.The lesion characteristics of the aorta in the control group and the model group were compared using HE staining.Western blot was used to detect the expression of zinc finger protein transcription factor 5(KLF5)in the aorta of the model group and the control group.qRT-PCR was used to detect the expression of miR-152 in the aorta of the model group and control group.The expression of apoptosis-related genes,cysteinyl aspartate specific proteinase-3(Caspase-3),B-cell lymphoma-2(BCL-2)and BCL-2 associated X protein(BAX)was detected in the model group and control group with western blot.The levels of inflammatory factors and blood lipids in the blood of the mice were measured,and the differences between the model group and the control group were compared.Western blot(WB)was used to detect changes in ?-catenin signaling pathways in the model group and normal mice,and to compare them.The mechanism by which miR-152 regulates the atherosclerosis through regulation of KLF5 is clarified.Macrophages in mice treated with ox-LDL of RAW264.7 cells used as cell model.Through experiments function gain and loss of the miR-152 in RAW264.7 cells in the inflammatory response function.Results:1.Constructing AS model mice,the model mice showed a significant increase in body weight after the experiment compared with the control mice.The results of HE staining in the aorta were normal in the control group,and the model group showed obvious AS lesion characteristics.2.The levels of inflammatory factors(IL-1,IL-6,TNF-a)in the blood of mice were detected.The results showed that all the three groups in the model group were increasedsignificantly compared to the control group.The levels of blood lipids(TC,TG,LDL,HDL)were measured.It was found that TC and LDL in the model group increased significantly,TG did not change much,and HDL decreased significantly.3.The results of the immunohistochemistry(IHC)staining showed the expression of KLF5 in the aorta of the model group was significantly increased compared to the control group.Western Blot(WB)result also found that KLF5 was highly expressed in the model group.Detection of apoptosis-regulating gene--Caspase-3,BCL-2 and BAX showed that the model group had high expression of Caspase-3 and BAX,and low expression of BCL-2.4.The mice in the model group were compared with the normal mice to detect changes in the 3-catenin signaling pathway(including ?-catenin,APC,GSK,AXIN,DSH,etc.).The results showed that the model group had high expression of ?-catenin,and the others remained unchanged.5.The expression of miR-152 in the aortic plaque tissue of model group was lower than the control group.6.miR-152 increases significantly reduced in RAW264.7 cell culture supernatant on ox-LDL mediated IL-1,IL-6 and higher expression of TNF alpha,and reduce the p-catenin expression,and the effect is the basis of miR-152 raised and KLF5 downgraded.Conclusions:miR-152 probably blocks the progression of AS by down-regulating KLF5 and decreasing ?-catenin expression.miR-152/KLF5 may be used as a therapeutic and diagnostic marker for AS.