Fig. 2

Microarray analysis and RT-qPCR verification. (a) Global comparison of differentially expressed genes (DEGs) in the control and leptin-induced groups is illustrated by heat maps. One-thousand and eight-hundred fifty-seven genes (p < 0.05, FC > 2.0) were found to be expressed at significantly different levels between the two groups, including 1197 upregulated and 660 downregulated genes. Upregulated genes are shown in the heat map in red color, down-regulated ones are in green color; evenly expressed genes are in black color. (b) Verification of microarray data on RT-qPCR. IL-1β, IGFBP6, MMP13, MMP3, BCL2L11, SYK and CTSK were up-regulated, while CHML, NVL and FRZB were down-regulated in the leptin-induced group when compared with the control group. Relative expression level was calculated as the mean value of six samples isolated from six different rats by using the delta Ct method. Expressions were normalized relative to that of the reference gene (β-actin). * indicates p < 0.05; ns = non- significant