Probablility of clinical onset in CR vs. AL G93A mice.

<p>Probability of clinical onset in 23 ad libitum (AL: •, 16 females; ▪, 7 males) and 31 calorie restricted (CR, 60% of ad libitum: ○, 21 females; □, 10 males) G93A mice. The rate of attaining clinical onset (i.e., the hazard ratio) in the CR mice was 2-fold higher (95% CI: 1.4, 4.7) than the AL mice. CR females had a 2-fold (95% CI: 1.2, 5.3) higher rate of attaining clinical onset as compared with AL females (P = 0.016). There was no sex difference in the rate of attaining clinical onset.</p

Functional measures in CR vs. AL G93A mice.

<p>(A) Ability to move and (B) paw grip endurance (s) of 23 ad libitum (AL: •, 16 females; ▪, 7 males) and 31 calorie restricted (CR, 60% of ad libitum: ○, 21 females; □, 10 males) G93A mice. Data are means ± SEM.</p

Correlation between clinical score and ability to move and between clinical score and paw grip endurance in CR vs. AL G93A mice.

<p>(A) Relation between clinical score (from clinical onset to euthanasia) and ability to move and (B) between clinical score and paw grip endurance (s) in 23 ad libitum (AL: •, 16 females; ▪, 7 males) and 31 calorie restricted (CR, 60% of ad libitum: ○, 21 females; □, 10 males) G93A mice. For ability to move, slopes and intercepts were not different with the following pooled equation: ability to move  =  (−1.4) x clinical score + (7.1). For paw grip endurance, data for the females followed a sigmoidal relationship (AL females, r² = 0.990; CR females, r² = 0.995; curves were significantly different, P<0.0001) whereas data for the males followed a linear relationship (slopes were significantly different, P = 0.0011). For AL males (r = −0.984, P<0.0001), paw grip endurance  =  (−27.8±1.1) x clinical score + (133.5±3.8); for CR males (r = −0.995, P<0.0001), paw grip endurance  =  (−31.8±0.7) x clinical score + (159.4±2.9), with the data presented as means ± SD. Data are means of each group on the same day.</p

SOD content in CR vs. AL G93A mice.

<p>(A) MnSOD was higher in CR vs. AL (3-fold, P = 0.031; main effect of diet), and in female vs. male (2.5-fold, P = 0.026; main effect of sex) red <i>gastrocnemius</i>. MnSOD was significantly elevated in CR vs. AL females (4-fold, P = 0.015), but not in CR vs. AL males. (B) MnSOD was higher in CR vs. AL white <i>gastrocnemius</i> (78%, P = 0.062; main effect of diet). MnSOD was higher in CR vs. AL females (2.2-fold, P = 0.038). (C) Cu/Zn-SOD was higher in CR vs. AL red <i>gastrocnemius</i> (67%, P = 0.096; main effect of diet). Cu/Zn-SOD was significantly higher in CR vs. AL females (2.6-fold, P = 0.020). (D) There was no change in Cu/Zn-SOD protein content in white <i>gastrocnemius</i>. Data are presented as means ± SEM. n = 27; AL, 7 males and 7 females; CR, 7 males and 6 females. Asterisks denote significant changes (P≤0.05 vs. AL); dagger denotes strong trend (0.05</p

Anthropometric measures in CR vs. AL G93A mice.

<p>(A) Food intake (g), (B) body weight (g) and (C) body condition of 23 ad libitum (AL: •, 16 females; ▪, 7 males) and 31 calorie restricted (CR, 60% of ad libitum: ○, 21 females; □, 10 males) G93A mice. Data are means ± SEM.</p

Probability of survival in CR vs. AL G93A mice.

<p>Probability of survival using as endpoint a clinical score of (A) 4 and (B) 5 in 23 ad libitum (AL: •, 16 females; ▪, 7 males) and 31 calorie restricted (CR, 60% of ad libitum: ○, 21 females; □, 10 males) G93A mice. The rate of reaching endpoint in the CR mice (i.e., the hazard ratio) was 3.1-fold higher (95% CI: 2.9, 10.7) than the AL mice. The rate of reaching endpoint was 3.1-fold (95% CI: 2.6, 13.5) higher in the CR vs. AL females (P<0.0001) and 3.4-fold (95% CI: 1.9, 20.7) higher in the CR vs. AL males (P = 0.003).</p

Apoptosis regulatory proteins content in the <i>quadriceps</i> of CR vs. AL G93A mice.

<p>(A) Bax was significantly higher in CR vs. AL mice (41%, P = 0.027; main effect of diet). Bax was increased in CR vs. AL females (52%, P = 0.048). (B) There was no significant difference in Bcl-2 protein content. (C) Bax/Bcl-2 was significantly higher in CR vs. AL mice (68%, P = 0.040; main effect of diet). Bax/Bcl-2 was increased in CR vs. AL females (2.3-fold, P = 0.029). No significant changes were observed in the protein content of: (D) caspase 9, (E) cleaved caspase 9, and (F) the ratio of cleaved caspase 9/caspase 9 for diet or sex. Data are presented as means ± SEM. n = 27; AL, 7 males and 7 females; CR, 7 males and 6 females. Asterisks denote significant changes (P≤0.05 vs. AL).</p

Catalase activity in CR vs. AL G93A mice.

<p>Catalase enzyme activity remained unchanged in the white <i>gastrocnemius</i> of G93A mice. Data are presented as means ± SEM. n = 27; AL, 7 males and 7 females; CR, 7 males and 6 females.</p

TNF-α content in CR vs. AL G93A mice.

<p>TNF-α was higher in the <i>quadriceps</i> of CR vs. AL mice (52%, P = 0.030; main effect of diet). Data are presented as means ± SEM. n = 27; AL, 7 males and 7 females; CR, 7 males and 6 females. Asterisks denote significant changes (P≤0.05 vs. AL).</p

Mitochondrial biogenesis and COX activity are impaired in frail old.

<p>(A) PGC-1α, CS, COX subunits- I, II, and IV, and phospho-GSK3β (Ser⁹) protein content, (B) citrate synthase and (C) mitochondrial complex IV activity (nmol.min⁻¹.mg of protein⁻¹) in the <i>vastus lateralis</i> of young, AO, and SO subjects (N = 10/group; ♀  =  ♂). (D) Mitochondrial complex IV activity (nmol.min⁻¹.mg of protein⁻¹) positively correlates (r = 0.77) with maximal isometric torque (N.m). Asterisk denotes significant changes <i>vs.</i> young, dagger denotes significant changes <i>vs.</i> AO, and double dagger denotes significant changes <i>vs.</i> both young and AO (P≤0.05).</p