Figure 4.

Effect of SPX synthesis blockade on leptin-induced changes in POMC and AgRP expression. Eight-week-old male mice were icv-injected with 2 μg of the AS or SCR ODN once a day for 2 days and fasted for 24 h after the second ODN injection. Then, mice were icv-injected with leptin (2.5 μg) and MBH samples were collected 3 h after leptin injection. (A,B) RNA samples were isolated from MBH tissues and were analyzed to determine POMC (A) and AgRP (B) mRNA levels using qRT-PCR. (C) ChIP assays showing the effect of AS ODN-mediated SPX synthesis blockade on the leptin (LEP)-induced increase in STAT3 binding onto the POMC and AgRP promoters. Nuclear DNA samples from MBH tissues were immunoprecipitated with anti-STAT3 antibody or mouse IgG and were analyzed by PCR amplification using primers specific to mouse POMC and AgRP promoters. Input represents the DNA extracted from the MBH before immunoprecipitation. Data are presented as mean ± S.E.M. *, p < 0.05.