Naoko Nose1, Rudolf A Werner2, Yuichiro Ueda3, Katharina Günther4, Constantin Lapa5, Mehrbod S Javadi6, Kazuhito Fukushima7, Frank Edenhofer4, Takahiro Higuchi8. 1. Comprehensive Heart Failure Center, University Hospital of Würzburg, Würzburg, Germany; Department of Nuclear Medicine, University Hospital of Würzburg, Würzburg, Germany; Stem Cell and Regenerative Medicine Group, Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany; Department of Biomedical Imaging, National Cerebral and Cardiovascular Research Center, Suita, Japan; Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, Suita, Japan. 2. Comprehensive Heart Failure Center, University Hospital of Würzburg, Würzburg, Germany; Department of Nuclear Medicine, University Hospital of Würzburg, Würzburg, Germany; Else-Kröner Forschungskolleg, University of Würzburg, Würzburg, Germany; Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, Baltimore, MD, United States. 3. Comprehensive Heart Failure Center, University Hospital of Würzburg, Würzburg, Germany; Stem Cell and Regenerative Medicine Group, Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany. 4. Stem Cell and Regenerative Medicine Group, Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany; Institute of Molecular Biology and CMBI, Department of Genomics, Stem Cell Biology and Regenerative Medicine, Leopold-Franzens-University Innsbruck, Innsbruck, Austria. 5. Department of Nuclear Medicine, University Hospital of Würzburg, Würzburg, Germany. 6. Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, Baltimore, MD, United States. 7. Department of Nuclear Medicine, University Hospital of Würzburg, Würzburg, Germany; Department of Biomedical Imaging, National Cerebral and Cardiovascular Research Center, Suita, Japan. 8. Comprehensive Heart Failure Center, University Hospital of Würzburg, Würzburg, Germany; Department of Nuclear Medicine, University Hospital of Würzburg, Würzburg, Germany; Department of Biomedical Imaging, National Cerebral and Cardiovascular Research Center, Suita, Japan; Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, Suita, Japan. Electronic address: thiguchi@me.com.
Abstract
BACKGROUND: Recent developments in cellular reprogramming technology enable the production of virtually unlimited numbers of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM). Although hiPSC-CM share various characteristic hallmarks with endogenous cardiomyocytes, it remains a question as to what extent metabolic characteristics are equivalent to mature mammalian cardiomyocytes. Here we set out to functionally characterize the metabolic status of hiPSC-CM in vitro by employing a radionuclide tracer uptake assay. MATERIAL AND METHODS: Cardiac differentiation of hiPSC was induced using a combination of well-orchestrated extrinsic stimuli such as WNT activation (by CHIR99021) and BMP signalling followed by WNT inhibition and lactate based cardiomyocyte enrichment. For characterization of metabolic substrates, dual tracer uptake studies were performed with 18F‑2‑fluoro‑2‑deoxy‑d‑glucose (18F-FDG) and 125I‑β‑methyl‑iodophenyl‑pentadecanoic acid (125I-BMIPP) as transport markers of glucose and fatty acids, respectively. RESULTS: After cardiac differentiation of hiPSCs, in vitro tracer uptake assays confirmed metabolic substrate shift from glucose to fatty acids that was comparable to those observed in native isolated human cardiomyocytes. Immunostaining further confirmed expression of fatty acid transport and binding proteins on hiPSC-CM. CONCLUSIONS: During in vitro cardiac maturation, we observed a metabolic shift to fatty acids, which are known as a main energy source of mammalian hearts, suggesting hi-PSC-CM as a potential functional phenotype to investigate alteration of cardiac metabolism in cardiac diseases. Results also highlight the use of available clinical nuclear medicine tracers as functional assays in stem cell research for improved generation of autologous differentiated cells for numerous biomedical applications.
BACKGROUND: Recent developments in cellular reprogramming technology enable the production of virtually unlimited numbers of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM). Although hiPSC-CM share various characteristic hallmarks with endogenous cardiomyocytes, it remains a question as to what extent metabolic characteristics are equivalent to mature mammalian cardiomyocytes. Here we set out to functionally characterize the metabolic status of hiPSC-CM in vitro by employing a radionuclide tracer uptake assay. MATERIAL AND METHODS: Cardiac differentiation of hiPSC was induced using a combination of well-orchestrated extrinsic stimuli such as WNT activation (by CHIR99021) and BMP signalling followed by WNT inhibition and lactate based cardiomyocyte enrichment. For characterization of metabolic substrates, dual tracer uptake studies were performed with 18F‑2‑fluoro‑2‑deoxy‑d‑glucose (18F-FDG) and 125I‑β‑methyl‑iodophenyl‑pentadecanoic acid (125I-BMIPP) as transport markers of glucose and fatty acids, respectively. RESULTS: After cardiac differentiation of hiPSCs, in vitro tracer uptake assays confirmed metabolic substrate shift from glucose to fatty acids that was comparable to those observed in native isolated human cardiomyocytes. Immunostaining further confirmed expression of fatty acid transport and binding proteins on hiPSC-CM. CONCLUSIONS: During in vitro cardiac maturation, we observed a metabolic shift to fatty acids, which are known as a main energy source of mammalian hearts, suggesting hi-PSC-CM as a potential functional phenotype to investigate alteration of cardiac metabolism in cardiac diseases. Results also highlight the use of available clinical nuclear medicine tracers as functional assays in stem cell research for improved generation of autologous differentiated cells for numerous biomedical applications.
Authors: Jolanda van der Velden; Birgit Goversen; Sofija Vučković; Rafeeh Dinani; Edgar E Nollet; Diederik W D Kuster; Jan Willem Buikema; Riekelt H Houtkooper; Miranda Nabben Journal: Stem Cell Res Ther Date: 2022-07-23 Impact factor: 8.079