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A metabolic switch toward lipid use in glycolytic muscle is an early pathologic event in a mouse model of amyotrophic lateral sclerosis.

Palamiuc L, Schlagowski A, Ngo ST, Vernay A, Dirrig-Grosch S, Henriques A, Boutillier AL, Zoll J, Echaniz-Laguna A, Loeffler JP, René F - EMBO Mol Med (2015)

Bottom Line: This mechanism represents a chronic pathologic alteration in muscle metabolism that is exacerbated with disease progression.Further, inhibition of pyruvate dehydrogenase kinase 4 activity with dichloroacetate delayed symptom onset while improving mitochondrial dysfunction and ameliorating muscle denervation.In this study, we provide the first molecular basis for the particular sensitivity of glycolytic muscles to ALS pathology.

View Article: PubMed Central - PubMed

Affiliation: INSERM, U1118 Mécanismes Centraux et Périphériques de la Neurodégénérescence, Strasbourg, France Université de Strasbourg UMRS1118, Strasbourg, France.

No MeSH data available.


Related in: MedlinePlus

Altered fuel preference in glycolytic muscle of 65-day-old asymptomatic SOD1G86R miceRelative mRNA levels of Pdk4 and Pdk2 evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± from age-matched WT. Pdk4: **P-values versus WT: 0.014 at 65 days and 0.018 at 105 days; Pdk2: ***P-value versus WT < 0.0001 at 105 days. n = 7 and 8 for WT and SOD1G86R, respectively, at 65 days; n = 5/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test.Relative mRNA levels of genes involved in lipid handling evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± SEM from age-matched WT. P-values versus WT: Lpl **P = 0.0009, Cd36 *P = 0.051, Acsf2 ***P < 0.0001 at 65 days, **P = 0.0059 at 105 days and Cpt-1β **P = 0.01 at 65 days and *P = 0.02 at 105 days (n = 6 and 7 for WT and SOD1G86R, respectively, at 65 days; n = 10 and 8 for WT and SOD1G86R, respectively, at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test).Relative levels of (left) ATP and (right) NADH and NAD+ measured in total tibialis anterior homogenates of WT and SOD1G86R mice. Left: Graphs represent mean fold change ± SEM in ATP from age-matched WT. **P = 0.002 (n = 9 and 12 for WT and SOD1G86R, respectively, at 65 days; n = 10/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test). Right: The amounts of NADH and NAD+ relative to protein content in whole tibialis anterior homogenates are represented as mean ± SEM. *P = 0.027 and **P = 0.001 (n = 5, Student's t-test).
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fig04: Altered fuel preference in glycolytic muscle of 65-day-old asymptomatic SOD1G86R miceRelative mRNA levels of Pdk4 and Pdk2 evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± from age-matched WT. Pdk4: **P-values versus WT: 0.014 at 65 days and 0.018 at 105 days; Pdk2: ***P-value versus WT < 0.0001 at 105 days. n = 7 and 8 for WT and SOD1G86R, respectively, at 65 days; n = 5/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test.Relative mRNA levels of genes involved in lipid handling evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± SEM from age-matched WT. P-values versus WT: Lpl **P = 0.0009, Cd36 *P = 0.051, Acsf2 ***P < 0.0001 at 65 days, **P = 0.0059 at 105 days and Cpt-1β **P = 0.01 at 65 days and *P = 0.02 at 105 days (n = 6 and 7 for WT and SOD1G86R, respectively, at 65 days; n = 10 and 8 for WT and SOD1G86R, respectively, at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test).Relative levels of (left) ATP and (right) NADH and NAD+ measured in total tibialis anterior homogenates of WT and SOD1G86R mice. Left: Graphs represent mean fold change ± SEM in ATP from age-matched WT. **P = 0.002 (n = 9 and 12 for WT and SOD1G86R, respectively, at 65 days; n = 10/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test). Right: The amounts of NADH and NAD+ relative to protein content in whole tibialis anterior homogenates are represented as mean ± SEM. *P = 0.027 and **P = 0.001 (n = 5, Student's t-test).

Mentions: In skeletal muscle, pyruvate levels are primarily governed by pyruvate dehydrogenase complex (PDH) activity, which itself is inhibited when phosphorylated by pyruvate dehydrogenase kinase 4 (PDK4). Thus, we assessed the expression levels of Pdk4 mRNA by RT–qPCR. As shown in Fig4A, at 65 days of age SOD1G86R mice had a 2.2-fold increase in Pdk4 mRNA levels in TA when compared to WT mice (Fig4A). At the end stage of disease, Pdk4 mRNA expression was 8.9-fold higher in SOD1G86R mice when compared to age-matched WT littermates. Noticeably, in the soleus muscle of SOD1G86R mice, Pdk4 expression was comparable to that of WT mice at 65 and 105 days of age (Supplementary Fig S3). By contrast, Pdk2 transcript levels were similar between SOD1G86R mice and WT littermates in TA and in soleus at 65 days of age, but decreased by 2- and 0.3-fold in these respective muscles at 105 days of age (Fig4A and Supplementary Fig S3). In SOD1G93A mice (Supplementary Fig S2C and D), Pdk4 mRNA levels were transiently increased by 50% at onset when mice develop signs of hindlimb weakness, prior to returning to control levels at end stage, while Pdk2 transcript levels were decreased by 50% from onset to end stage when compared to WT littermates. In muscle biopsies of definite ALS patients (Supplementary Fig S4), Pdk4 mRNA levels were increased 3-fold while Pdk2 mRNA levels remained unchanged when compared to controls.


A metabolic switch toward lipid use in glycolytic muscle is an early pathologic event in a mouse model of amyotrophic lateral sclerosis.

Palamiuc L, Schlagowski A, Ngo ST, Vernay A, Dirrig-Grosch S, Henriques A, Boutillier AL, Zoll J, Echaniz-Laguna A, Loeffler JP, René F - EMBO Mol Med (2015)

Altered fuel preference in glycolytic muscle of 65-day-old asymptomatic SOD1G86R miceRelative mRNA levels of Pdk4 and Pdk2 evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± from age-matched WT. Pdk4: **P-values versus WT: 0.014 at 65 days and 0.018 at 105 days; Pdk2: ***P-value versus WT < 0.0001 at 105 days. n = 7 and 8 for WT and SOD1G86R, respectively, at 65 days; n = 5/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test.Relative mRNA levels of genes involved in lipid handling evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± SEM from age-matched WT. P-values versus WT: Lpl **P = 0.0009, Cd36 *P = 0.051, Acsf2 ***P < 0.0001 at 65 days, **P = 0.0059 at 105 days and Cpt-1β **P = 0.01 at 65 days and *P = 0.02 at 105 days (n = 6 and 7 for WT and SOD1G86R, respectively, at 65 days; n = 10 and 8 for WT and SOD1G86R, respectively, at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test).Relative levels of (left) ATP and (right) NADH and NAD+ measured in total tibialis anterior homogenates of WT and SOD1G86R mice. Left: Graphs represent mean fold change ± SEM in ATP from age-matched WT. **P = 0.002 (n = 9 and 12 for WT and SOD1G86R, respectively, at 65 days; n = 10/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test). Right: The amounts of NADH and NAD+ relative to protein content in whole tibialis anterior homogenates are represented as mean ± SEM. *P = 0.027 and **P = 0.001 (n = 5, Student's t-test).
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fig04: Altered fuel preference in glycolytic muscle of 65-day-old asymptomatic SOD1G86R miceRelative mRNA levels of Pdk4 and Pdk2 evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± from age-matched WT. Pdk4: **P-values versus WT: 0.014 at 65 days and 0.018 at 105 days; Pdk2: ***P-value versus WT < 0.0001 at 105 days. n = 7 and 8 for WT and SOD1G86R, respectively, at 65 days; n = 5/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test.Relative mRNA levels of genes involved in lipid handling evaluated by qPCR at the indicated ages in tibialis anterior of WT and SOD1G86R mice. Graphs represent mean fold change ± SEM from age-matched WT. P-values versus WT: Lpl **P = 0.0009, Cd36 *P = 0.051, Acsf2 ***P < 0.0001 at 65 days, **P = 0.0059 at 105 days and Cpt-1β **P = 0.01 at 65 days and *P = 0.02 at 105 days (n = 6 and 7 for WT and SOD1G86R, respectively, at 65 days; n = 10 and 8 for WT and SOD1G86R, respectively, at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test).Relative levels of (left) ATP and (right) NADH and NAD+ measured in total tibialis anterior homogenates of WT and SOD1G86R mice. Left: Graphs represent mean fold change ± SEM in ATP from age-matched WT. **P = 0.002 (n = 9 and 12 for WT and SOD1G86R, respectively, at 65 days; n = 10/genotype at 105 days, two-way ANOVA followed by Fisher's LSD post hoc test). Right: The amounts of NADH and NAD+ relative to protein content in whole tibialis anterior homogenates are represented as mean ± SEM. *P = 0.027 and **P = 0.001 (n = 5, Student's t-test).
Mentions: In skeletal muscle, pyruvate levels are primarily governed by pyruvate dehydrogenase complex (PDH) activity, which itself is inhibited when phosphorylated by pyruvate dehydrogenase kinase 4 (PDK4). Thus, we assessed the expression levels of Pdk4 mRNA by RT–qPCR. As shown in Fig4A, at 65 days of age SOD1G86R mice had a 2.2-fold increase in Pdk4 mRNA levels in TA when compared to WT mice (Fig4A). At the end stage of disease, Pdk4 mRNA expression was 8.9-fold higher in SOD1G86R mice when compared to age-matched WT littermates. Noticeably, in the soleus muscle of SOD1G86R mice, Pdk4 expression was comparable to that of WT mice at 65 and 105 days of age (Supplementary Fig S3). By contrast, Pdk2 transcript levels were similar between SOD1G86R mice and WT littermates in TA and in soleus at 65 days of age, but decreased by 2- and 0.3-fold in these respective muscles at 105 days of age (Fig4A and Supplementary Fig S3). In SOD1G93A mice (Supplementary Fig S2C and D), Pdk4 mRNA levels were transiently increased by 50% at onset when mice develop signs of hindlimb weakness, prior to returning to control levels at end stage, while Pdk2 transcript levels were decreased by 50% from onset to end stage when compared to WT littermates. In muscle biopsies of definite ALS patients (Supplementary Fig S4), Pdk4 mRNA levels were increased 3-fold while Pdk2 mRNA levels remained unchanged when compared to controls.

Bottom Line: This mechanism represents a chronic pathologic alteration in muscle metabolism that is exacerbated with disease progression.Further, inhibition of pyruvate dehydrogenase kinase 4 activity with dichloroacetate delayed symptom onset while improving mitochondrial dysfunction and ameliorating muscle denervation.In this study, we provide the first molecular basis for the particular sensitivity of glycolytic muscles to ALS pathology.

View Article: PubMed Central - PubMed

Affiliation: INSERM, U1118 Mécanismes Centraux et Périphériques de la Neurodégénérescence, Strasbourg, France Université de Strasbourg UMRS1118, Strasbourg, France.

No MeSH data available.


Related in: MedlinePlus