Fig. 4

General features of glucose utilization and fat distribution in mstnb-deficient zebrafish. (A) The dynamic serum glucose levels of zebrafish after a chow diet. The solid line represents wild-type control zebrafish, and the dotted line represents mstnb-deficient zebrafish. (B) Representative fluorescent image of adipose tissue of a wild-type control zebrafish (upper panel) and an mstnb-deficient zebrafish (lower panel) at the adult stage (90 dpf) stained with Nile red under an excitation wave length of 470 nm. A marked decrease in the intensity of the subcutaneous adipose tissue staining (indicated by dotted curve) was observed in the mstnb-deficient adults (bottom panel) compared with the wild-type control fish (upper panel). (C) The quantification analysis of fluorescence intensity of Nile Red staining using Image J software. (D) No significant difference in body fat ratio (total fat/body weight) was observed between mstnb-deficient and wild-type control zebrafish. (E) TG content analysis of skeletal muscle indicated elevated accumulation of TG. Five pairs of zebrafish were used for analysis. The skeletal muscle tissue was dissected in the same position, and the muscle tissue was weighed. (F) Increased fat accumulation in the muscle tissue of mstnb-deficient zebrafish compared with wild-type control fish. Diagram on the left panel shows the location of muscle tissue for cross-cryosectioning and Oil red O staining of muscle tissue from adult zebrafish in the right panel. D, dorsal side; V, ventral side.