CPT1A plays a key role in the development and treatment of multiple sclerosis and experimental autoimmune encephalomyelitis

Abstract

Human mutations in carnitine palmitoyl transferase 1A (CPT1A) are correlated with a remarkably low prevalence of multiple sclerosis (MS) in Inuits (P479L) and Hutterites (G710E). To elucidate the role of CPT1A, we established a Cpt1a P479L mouse strain and evaluated its sensitivity to experimental autoimmune encephalomyelitis (EAE) induction. Since CPT1a is a key molecule in lipid metabolism, we compared the effects of a high-fat diet (HFD) and normal diet (ND) on disease progression. The disease severity increased significantly in WT mice compared to that in Cpt1 P479L mice. In addition, WT mice receiving HFD showed markedly exacerbated disease course when compared either with Cpt1a P479L mice receiving HFD or WT control group receiving ND. Induction of EAE caused a significant decrease of myelin basic protein expression in the hindbrain of disease affected WT mice in comparison to Cpt1a P479L mice. Further, WT mice showed increased expression of oxidative stress markers like Nox2 and Ho-1, whereas expression of mitochondrial antioxidants regulator Pgc1α was increased in Cpt1a P479L mice. Our results suggest that, lipids metabolism play an important role in EAE, as shown by the higher severity of disease progression in both WT EAE and WT EAF HFD-fed mice in contrast to their counterpart Cpt1a P479L mutant mice. Interestingly, mice with downregulated lipid metabolism due to the Cpt1a P479L mutation showed resistance to EAE induction. These findings support a key role for CPT1A in the development of EAE and could be a promising target in MS treatment.

Dysregulation of metabolic pathways by carnitine palmitoyl-transferase 1 plays a key role in central nervous system disorders: experimental evidence based on animal models

“…Here, we have presented that MS, ALS, and PD are characterized by local, and systemic changes in metabolism. Based on a CPT1A mutation found in the Inuit population, which seems to confer resistance to neurodegeneration by reducing CPT1A activity by 78%, we decided to test the effect of CPT1A de-activation in neurodegeneration in two ways: by pharmacologically blocking CPT1, and by creating a new Cpt1a p479l mice 26 . The findings from this study revealed that the Cpt1a-mutated mice are resistant to the development of not only EAE, but also PD and to some extent ALS.…”

“…To examine the role of CPT1A activity, a mouse line (B6J-Cpt1a < em1Nki >) expressing the Inuit mutant allele Cpt1a P479L (Cpt1a < em1Nki > , MGI number: 5810634) was generated and genotyped as previously described 26 .…”

“…Litters were genotyped using DNA extracted from ear punch tissue using DNA kit (Zymo Research). Mice were genotyped by RT-qPCR using for the expression of the Sod1 g93a mutation using primer sequences: (SOD1 G93A forward: GGG AAG CTG TTG TCC CAA G, SOD1 G93A reverse: CAA GGG GAG GTA AAA GAG AGC, Internal positive control forward: CAC GTG GGC TCC AGC ATT, Internal positive control reverse: TCA CCA GTC ATT TCT GCC TTT G) (TAG Copenhagen) and the previously mentioned primer sequences for Cpt1a p479l 26 . RT-qPCR was performed as described below.…”

“…All mice received an intraperitoneal injection of 500 ng pertussis toxin (Sigma-Aldrich) on the day of immunization and 2 days later. The mice were monitored daily and weighed and scored clinically according to a scale from 0 to 5 26 . The mice were not permitted to lose more than 20% body weight and to go beyond score 4.…”

“…Mice were acclimated for 3 weeks at 21 °C in a high barrier animal facility. Cpt1a p479l mice were generated and breed as previously described 26 . Mice were 9 weeks old when the experiment initiated.…”