DCA Effects in ALS Models Figure 4. DCA increases mean survival of SOD1G93A transgenic mice. Kaplan-Meyer survival curves from DCA-treated and control SOD1G93A male (A) and female (B) mice. DCA was administered in drinking water from 70 days of age until death as detailed in materials and methods. 9 animals per group, p,0.05, Kaplan-Meyer log-rank test. doi:10.1371/journal.pone.0034776.g004 Figure 5. DCA delays loss of grip strength and neuromuscular junction shrinkage in SOD1G93A mice. A) Hind-limb grip strength records from non Tg or SOD1G93A male mice treated with DCA or vehicle as indicated. DCA-treated non Tg animals did not show differences with control ones and data are not shown in order to simplify the graph. Data are mean 6 SEM from 9 animals per group. *p,0.05, significantly different from SOD1G93A control. B) ACh receptors labeled with TMR-BgTx in representative EDL neuromuscular junctions from non Tg (top), SOD1G93A control (middle) or DCA-treated SOD1G93A (bottom). Quantification of total TMR-BgTx-stained neuromuscular area in the different groups of animals. Data are expressed as percentage of non Tg control, mean 6 SEM from 15–35 neuromuscular junctions from 2–4 animals per group. *p,0.05, significantly different from non Tg control. **p,0.05, significantly different from SOD1G93A control. Scale bar: 30 mm. doi:10.1371/journal.pone.0034776.g005 for the SOD1G93A mice when compared to non Tg littermates (Fig. 7 left column). DCA treatment rescued 25% of motor neurons at the lumbar level (Rexed lamina IX). In addition, we assayed astrocytic GFAP immunoreactivity in the spinal cord as a cellular element contributing to disease progression [8]. Astrocyte reactivity as determined by GFAP immunofluorescence was increased in the SOD1G93A mice in contrast to non Tg littermates as previously described [21,22]. DCA treatment induced a marked reduction (70%) in GFAP immunoreactivity in the spinal cord, when compared to the vehicle-treated group (Fig. 7 right column). Discussion It is intriguing that rat [4], mouse [10,11] and also human [23] astrocytes expressing mutated SOD1 exert toxic effects on motor neurons. Here, we report that DCA was sufficient to reverse mitochondrial dysfunction in astrocytes from SOD1G93A rats and, at the same time, the phenotypic features that make astrocytes toxic for motor neurons. Significantly, we provide convincing Figure 6. DCA improves mitochondrial function in the spinal cord of SOD1G93A mice. Calculated respiratory control ratio (RCR) for spinal cord mitochondria from non Tg or SOD1G93A mice treated with DCA or vehicle as indicated. Data are mean 6 SEM from three independent experiments. *p,0.05, significantly different from non Tg control. **p,0.05, significantly different from SOD1G93A control. doi:10.1371/journal.pone.0034776.g006 PLoS ONE | www.plosone.org 4 April 2012 | Volume 7 | Issue 4 | e34776