Figure 1. Ameliorated serum in β-hydroxybutyrate (HB)-treated aged rats. HB was administered to aged rats (n = 4 each). (A) Serum insulin, (B) glucose levels, (C) Ketone body, and (D) Leptin were measured after 30 days of HB treatment. ##p < 0.01, ###p < 0.001 vs. Young; *p < 0.05, **p < 0.01, ***p < 0.001 vs. Old.