Previous studies have shown that chitosan activates the PPAR activity in adipocytes [13]. We further analyzed the in vivo PPAR activity after chitosan administration and the targeted organs that chitosan acted on by bioluminescent imaging. Figure 3(A) shows that chitosan gradually increased the luminescence intensity, reached a maximal intensity on 3 d, and gradually decreased the luminescent signals. We further sacrificed mice on 3 d after administration, and ex vivo imaging showed that chitosan significantly induced PPAR-dependent bioluminescent signals in brain (1.75 fold) and stomach (2.54 fold) (Figure 3(B)). These findings indicated that administration of chitosan activated PPAR activities in brain and stomach.
