Identification of coordinately regulated microRNA-gene networks that differ in baboons discordant for LDL-Cholesterol

Although the mechanisms underlying development of atherosclerosis are not well understood, LDL-C is known to influence expression of endothelial microRNAs (miRNAs) and gene-targets of miRNAs to promote cell senescence. However, the impact of LDL-C on expression of PBMC miRNAs and miRNA targeted genes in response to an atherogenic diet is not known. We hypothesized that miRNA expression profiles differ between baboons with low and high serum low-density lipoprotein cholesterol (LDL-C) concentrations in response to diet, and that microRNA-gene networks in baboons discordant for LDL-Cholesterol We generated small RNA libraries from baboons differing in their LDL-C response to dietary fat and cholesterol (low LDL-C, n = 3; high LDL-C, n = 3) using liver biopsies collected before and after a high-cholesterol, high-fat (HCHF) challenge diet. We sequenced the libraries using Next-Generation Illumina sequencing methods, analyzed the data using mirTools software and identified 517 baboon miRNAs: 490 homologous to human and 27 novel miRNAs. HCHF diet elicited expression of more miRNAs compared to baseline (chow) diet for both low and high LDL-C baboons. Seventeen miRNAs exhibited significant differential expression in response to HCHF diet in high LDL-C baboons compared to nine miRNAs in low LDL-C baboons. Putative miRNA targets were identified with TargetScan/Base tools. miRNAs significantly targeted more genes in high LDL-C baboons compared to low LDL-C responders. Further, we identified miRNA isomers and other non-coding RNAs that were differentially expressed in response to the challenge diet.Our discovery of differentially expressed baboon miRNAs and their targets is a fundamental step in understanding the role of non-coding RNAs in the modulation of dsylipidemia. Assess the differential miRNAs and genes response to a high-cholesterol, high-fat diet in blood of low and high LDL-C baboons, and identify potential miRNA targets and corodinated network. --------------------------------------- This represents the mRNA component only