Research Paper Volume 4, Issue 12 pp 899—916

Mechanistic or mammalian target of rapamycin (mTOR) may determine robustness in young male mice at the cost of accelerated aging

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Figure 2. Comparison of pS6 and p-Akt levels in the hearts of 6 month old females and males. (A) Immunoblot analysis of protein lysates from the hearts of 6 months old females and males, which were fed ad libitum, fasted overnight for blood collection and then re-fed for 2 hours. Numbers above blots represent individual mice. All mice, except numbers 21-30 underwent this schedule and were well fed before organ collection. In addition some females (21-30) received food ad libitum all the time (without transient fasting). Two conditions were considered as fed ad libitum (at least for 2 hours before sacrifice and organ collection). There was no difference in pS6 and Akt between two subgroups of mice (numbers 1-10 versus 21-30). Also there was no difference between levels of insulin and triglycerides in two sub-groups of females (Fig. 1S), confirming that they were of similar feeding status at the time of organ collection. Because of that we combined two female subgroups for further statistical analysis to increase statistical power to compare with males that were all similar re-fed for 2 hours as females. Now, all comparison of pS6 and p-AKT could be done between males and females as fed ad libitum for the last 2 hours.

Quantitative analysis of data shown in Figure 2A. (B) Quantified intensities of phosphorylated S6 (pS6) signal in the hearts of female (n=20) and male (n=10) mice. Data are presented as mean ± SE. (C) Quantified intensities of p-AKT signal in the hearts of female (n=20) and male (n=10) mice. Data are presented as mean ± SE. (D) Correlation between levels of pS6 and p-AKT in the hearts. r – Pearson coefficient. (E) Correlation between levels of pS6 (in hearts) and an increase in insulin levels upon re-feeding in both females and males taken together.