Neutral Lipid Storage Disease with Myopathy (NLSDM) is a very rare disorder characterized by a defect in the degradation of cytoplasmic triglycerides and accumulation as lipid droplets (LDs). This lipid dysmetabolism may determine progressive myopathy, cardiomyopathy, diabetes, hepatomegaly, hepatic steatosis, chronic pancreatitis and short stature. No specific therapy is currently available. All patients carry damaging mutations in the PNPLA2 gene, which codifies for the adipose triglyceride lipase (ATGL), an enzyme that hydrolyses fatty acids from triacylglycerol. We have previously reprogrammed dermal fibroblasts from two patients and healthy subjects into induced pluripotent stem cells (iPSCs). The iPSCs were tested for pluripotency evaluating the expression of TRA-1-81, SSEA4 and OCT4 markers, and their differentiation ability into three-germ layers by immunofluorescence analysis (β-III tubulin, ectoderm; SMA, mesoderm; FOXA2, endoderm). Now we demonstrate that NLSDM-iPSCs present an abnormal accumulation of triglycerides into LDs, resembling the hallmark of NLSDM. Indeed, immunofluorescence analysis shows that NLSDM-iPSCs has 20 times more LDs and almost 5 larger LDs then control iPSCs. Moreover, the TG content of NLSDM-iPSCs is significant higher than that of control iPSCs. Oleic acid pulse chase experiments further confirm that lipase activity is impaired in NLSDM-iPSCs compared to control cells. These results demonstrate that iPSCs recapitulate NLSDM specific-lipid metabolism defect and can be considered a valid biochemical disease model. Finally, NLSDM-iPSCs could be differentiated into cardiac myocytes or myoblasts to screen potential therapeutic compounds
Functional and biochemical characterization of induced Pluripotent Stem cells (iPSCs) from patients with Neutral Lipid Storage Disease with Myopathy
DELL'ERA, Patrizia;MORA, Cristina;
2017-01-01
Abstract
Neutral Lipid Storage Disease with Myopathy (NLSDM) is a very rare disorder characterized by a defect in the degradation of cytoplasmic triglycerides and accumulation as lipid droplets (LDs). This lipid dysmetabolism may determine progressive myopathy, cardiomyopathy, diabetes, hepatomegaly, hepatic steatosis, chronic pancreatitis and short stature. No specific therapy is currently available. All patients carry damaging mutations in the PNPLA2 gene, which codifies for the adipose triglyceride lipase (ATGL), an enzyme that hydrolyses fatty acids from triacylglycerol. We have previously reprogrammed dermal fibroblasts from two patients and healthy subjects into induced pluripotent stem cells (iPSCs). The iPSCs were tested for pluripotency evaluating the expression of TRA-1-81, SSEA4 and OCT4 markers, and their differentiation ability into three-germ layers by immunofluorescence analysis (β-III tubulin, ectoderm; SMA, mesoderm; FOXA2, endoderm). Now we demonstrate that NLSDM-iPSCs present an abnormal accumulation of triglycerides into LDs, resembling the hallmark of NLSDM. Indeed, immunofluorescence analysis shows that NLSDM-iPSCs has 20 times more LDs and almost 5 larger LDs then control iPSCs. Moreover, the TG content of NLSDM-iPSCs is significant higher than that of control iPSCs. Oleic acid pulse chase experiments further confirm that lipase activity is impaired in NLSDM-iPSCs compared to control cells. These results demonstrate that iPSCs recapitulate NLSDM specific-lipid metabolism defect and can be considered a valid biochemical disease model. Finally, NLSDM-iPSCs could be differentiated into cardiac myocytes or myoblasts to screen potential therapeutic compoundsI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
