The identification of differentially expressed genes in liver of wild-type and ob/ob mice at ad libitum feeding

Postprandial hyperglycemia and hypertriglyceridemia caused by dysregulated hepatic metabolism in obese subjects are closely related to onset of Type 2 Diabetes. We measured transcriptomic data in liver of WT and ob/ob mice, and identified genes that showed significantly different expression in ob/ob mice compared with WT mice as differentially expressed genes. We used the liver of 10-week-old male wild-type (WT) and leptin-deficient obese (ob/ob) mice at ad libitum feeding (n = 5). Livers were removed and frozen in liquid nitrogen, in further pulverized with dry ice to a fine powder and separated into tubes. Total RNA extraction from liver samples collected at ad libitum feeding was performed by using the RNeasy Mini Kit (QIAGEN, Germantown, MD, USA) and QIAshredder (QIAGEN). The extracted RNA was assessed for quantity using Nanodrop (Thermo Fisher Scientific, Waltham, MA, USA) and the quality was evaluated by using the 2100 Bioanalyzer (Agilent Technologies, Santa Clara, CA, USA). The TruSeq Stranded mRNA Kit (Illumina, San Diego, CA, USA) was used to generate complementary DNA (cDNA) libraries. On the Illumina Novaseq6000 Platform (Illumina), 150 base pair (bp) paired-end sequencing of the resulting cDNAs was performed.