Osteoglycin deletion affects glucose and insulin homeostasis. (A–B) Glucose and (C–D) insulin levels during a glucose tolerance test shown either as a time course (A, C) or expressed as area under the curve (B, D) for Ogn−/− and wildtype (WT) mice on both chow and high fat diet. (E) Glucose levels during an insulin tolerance test shown as a time course and (F) expressed as area under the curve for Ogn−/− and WT mice on both chow and high fat diet. (G) Serum glucose and (H) serum insulin levels in Ogn−/− and WT mice on both chow and high fat diet at cull at 16 weeks of age. Histological analysis showing (I) number of islets and (J) beta cell area in the pancreas of Ogn−/− and WT mice on chow diet. Data are means ± SEM of at least 10 mice per group, except 4–6 mice per group for islet histology (I–J). * = p < 0.05, ** = p < 0.01, *** = p < 0.001 between chow groups or as indicated; # = p < 0.05, ## = p < 0.01 between HFD groups.