Figure 4. The influence of cardiac dSir2 overexpression on the heart in 7-weeek-old flies. (A) Cardiac dSir2 expression. (B) Cardiac Foxo expression. (C) Cardiac SOD activity level. (D) Cardiac MDA level. (E) Cardiac TAG level. (F) Cardiac bmm expression. (G) Heart period. (H) Heart systolic period. (I) Heart diastolic period. (J) Heart diastolic dysfunction index. The diastolic dysfunction index is diastolic interval standard deviation/diastolic interval median). (K) Fractional shortening. (L) Diastolic diameter. (M) Systolic diameter. (N) Microscopic image of cardiac function from M-mode trace. It can be observed that the cardiac dSir2 overexpression could increase heart period and fractional shortening, and decrease diastolic dysfunction. (O) Cardiac dnaJ-H expression level. One-way analysis of variance (ANOVA) with least significant difference (LSD) tests were used to identify differences among the hand-Gal4>w11118, UAS-dSir2-overexpression>w11118, and hand-Gal4>UAS-dSir2-overexpression flies to explore the effects of cardiac dSir2 overexpression on aging hearts. Data are represented as means ± SEM. *P<0.05; **P <0.01. The sample size was the same as in our previous experiments.