Figure 4. Excess adiponectin normalizes pancreatic islet histology and improves both local and systemic inflammation.

(A) Immunofluorescence staining for insulin (green) and glucagon (red) was performed in pancreatic sections from 10-week-old male WT mice (top), ob/ob littermates (middle), and adiponectin transgenic ob/ob mice. (B) Immunohistochemical staining of gonadal adipose tissue with anti-F4/80 antibodies suggests reduced infiltration of macrophages. Note that the difference in average adipocyte size between the 2 genotypes is apparent but less pronounced at this younger age. (C) FACS analysis of the stromal vascular fraction using F4/80 antibodies (left) and qRT-PCR for F4/80 (right) (n = 10 mice/group) were performed in gonadal WAT of adiponectin transgenic ob/ob mice and ob/ob littermates. Black curve shows control IgG staining; red curve shows anti-F4/80 staining. (D) mRNA levels of vWF and VCAM-1 from WAT were measured by qRT-PCR. A ratio of VCAM-1/vWF is provided as an indicator of local inflammation in the vascular endothelium. (E) Circulating IL-6 was measured in adiponectin transgenic ob/ob mice and ob/ob littermates (top); adipose tissue TNF-α message levels (bottom). (C–E) For these studies, 14-week-old male mice were used (n = 10 mice/group). *P < 0.05. Panels C–E were analyzed by Student’s t test.