A MYOPATHY WITH UNUSUAL FEATURES CAUSED BY PNPLA2 GENE MUTATIONS

作者：Pennisi Elena M^*; Missaglia Sara; Dimauro Salvatore; Bernardi Cinzia; Akman Hasan Orhan; Tavian Daniela

来源：Muscle & Nerve, 2015, 51(4): 609-613.

DOI：10.1002/mus.24477

• ATGL enzyme
• lipid metabolism
• lipid myopathy
• lipid storage
• PNPLA2 gene

Introduction: The PNPLA2 gene encodes the enzyme adipose triglyceride lipase (ATGL), which catalyzes the first step of triglyceride hydrolysis. Mutations in this gene are associated with an autosomal recessive lipid-storage myopathy, neutral lipid-storage disease with myopathy (NLSD-M). Results: A 72-year-old woman had late-onset myopathy, with mild weakness, cramps, and exercise intolerance. Electromyography showed myotonic discharges. A few leukocytes showed lipid droplets (Jordan anomaly). Deltoid and quadriceps muscle biopsies showed no lipid storage. Genetic analysis of PNPLA2 detected 2 heterozygous mutations: c.497A>G (p.Asp166Gly) in exon 5 and c.1442C>T (p.Pro481Leu) in exon 10. Expression of mutant PNPLA2 plasmids in HeLa cells resulted in impaired enzyme activity, confirming the pathological effects of the mutations. Conclusions: In this case of NLSD-M, the myopathy may be due to a metabolic defect rather than to a mechanical effect of lipid storage. This suggests that more than 1 mechanism contributes to muscle damage in NLSD-M. Muscle Nerve 51: 609-613, 2015

• 出版日期2015-4