Novel role of mitochondrial fusion factor Mfn1 in neural differentiation of human iPS cells

Abstract Background Nicotinamide phosphoribosyltransferase (NAMPT) regulates cellular functions through the protein deacetylation activity of nicotinamide adenine dinucleotide (NAD+)-dependent sirtuins (SIRTs). SIRTs regulate functions of histones and none-histone proteins. The role of NAMPT/SIRT pathway in the regulation of maintenance and differentiation of human-induced pluripotent stem (iPS) cells is not fully elucidated. Methods We evaluated the effects of specific inhibitors of NAMPT or SIRT2 on the pluripotency, proliferation, survival, and hematopoietic differentiation of human iPS cells. We also studied the molecular mechanism downstream of NAMPT/SIRTs in iPS cells. Results We demonstrated that NAMPT is indispensable for the maintenance, survival, and hematopoietic differentiation of iPS cells. We found that inhibition of NAMPT or SIRT2 in iPS cells induces p53 protein by promoting its lysine acetylation. This leads to activation of the p53 target, p21, with subsequent cell cycle arrest and induction of apoptosis in iPS cells. NAMPT and SIRT2 inhibition also affect hematopoietic differentiation of iPS cells in an embryoid body (EB)-based cell culture system. Conclusions Our data demonstrate the essential role of the NAMPT/SIRT2/p53/p21 signaling axis in the maintenance and hematopoietic differentiation of iPS cells.

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Abstract 15961: Syncytial Model of Type 2 Long QT Syndrome Derived From Human iPS Cells Can Be Paced and Responds to Ikr Block and Activation

Circulation ◽

10.1161/circ.130.suppl_2.15961 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Renjun Zhu ◽

Rosy Joshi-Mukherjee ◽

Adriana Blazeski ◽

Kenneth R Boheler ◽

Gordon F Tomaselli ◽

...

Keyword(s):

Drug Effects ◽

Ips Cells ◽

Herg Channel ◽

Long Qt ◽

Human Ips Cells ◽

Cycle Lengths ◽

Channel Mutation ◽

Diastolic Potential

Type 2 long QT (LQT2) syndrome is a cardiac disorder associated with hERG channel mutation that may lead to tachyarrhythmia and sudden death. We developed a syncytial model of cardiomyocytes (CMs) differentiated from iPS cells derived from an LQT2 patient harboring an A422T mutation. The A422T mutation has been shown to cause a marked decrease in IKr current mainly due to a trafficking defect in the hERG channel. Immunostaining of cTnI revealed that CMs were isotropically distributed with well-formed sarcomeres. Both wild type (WT) and LQT2 monolayers were stable in culture for at least 60 days with spontaneous activity, and could be paced at cycle lengths (CL) from 2000 down to 300 ms. After staining the monolayers with di-4-ANEPPS, optical mapping showed that all monolayers formed a functional syncytium that supported propagating action potentials. LQT2 monolayers had longer APD80s than WT monolayers (332±43 ms, n=6, vs. 267±46 ms, n=18, mean±SD, CL = 700 ms, p<0.005), showing the delayed repolarization expected of the LQT2 phenotype. Reentrant spiral waves were observed in LQT2 (n=2), but not WT monolayers. Application of 0.2μM E-4031 (IKr blocker) slowed repolarization and prolonged APD80 in both WT and LQT2 monolayers, and slowed conduction velocity in WT monolayers (4.7±1.0 cm/s, n=6 vs. 10.4±1.4 cm/s, n=11 control, CL = 1000 ms). The slowing effect may reflect a role of IKr in setting the maximum diastolic potential in these CMs where IK1 is weakly expressed, as has been recently suggested. Application of 10μM ML-T531 (IKr activator) shortened APD80 in LQT2 monolayers (313±36 ms vs. 162±19 ms, n=4, p<0.0001), showing successful reversal of the LQT phenotype. ML-T531 also shortened APD80 in WT monolayers (202±43 ms vs. 154±26 ms, n=4, p<0.04). These results indicate that syncytial models of heritable cardiac disease are feasible and may be useful for studying drug effects that affect electrophysiology and arrhythmogenesis.

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Evaluation of human iPS cells by neural differentiation and tumorigenicity

Rinsho Shinkeigaku ◽

10.5692/clinicalneurol.51.1079 ◽

2011 ◽

Vol 51 (11) ◽

pp. 1079-1080 ◽

Cited By ~ 1

Author(s):

Yohei Okada ◽

Hideyuki Okano

Keyword(s):

Neural Differentiation ◽

Ips Cells ◽

Human Ips Cells

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Evaluation of developmental neurotoxicity using neural differentiation potency in human iPS cells

Proceedings for Annual Meeting of The Japanese Pharmacological Society ◽

10.1254/jpssuppl.92.0_3-p-127 ◽

2019 ◽

Vol 92 (0) ◽

pp. 3-P-127

Author(s):

Shigeru Yamada ◽

Daiju Yamazaki ◽

Yasunari Kanda

Keyword(s):

Neural Differentiation ◽

Ips Cells ◽

Developmental Neurotoxicity ◽

Human Ips Cells

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NAMPT/SIRT2–mediated inhibition of the p53-p21 signaling pathway is indispensable for maintenance and hematopoietic differentiation of human iPS cells

10.21203/rs.3.rs-22092/v1 ◽

2020 ◽

Author(s):

Julia Skokowa ◽

Yun Xu ◽

Masoud Nasri ◽

Benjamin Dannenmann ◽

Perihan Mir ◽

...

Keyword(s):

Embryoid Body ◽

P53 Protein ◽

Ips Cells ◽

Hematopoietic Differentiation ◽

Cellular Functions ◽

Nicotinamide Phosphoribosyltransferase ◽

Signaling Axis ◽

Human Ips Cells ◽

Induced Pluripotent

Abstract Background: Nicotinamide phosphoribosyltransferase (NAMPT) regulates cellular functions through the protein deacetylation activity of nicotinamide adenine dinucleotide (NAD+)-dependent sirtuins (SIRTs). SIRTs regulate functions of histones and none-histone proteins. The role of NAMPT/SIRTs pathway in the regulation of maintenance and differentiation of human induced pluripotent stem (iPS) cells is not fully elucidated. Methods: We evaluated the effects of specific inhibitors of NAMPT-, or SIRT2 on the pluripotency, proliferation, survival and hematopoietic differentiation of human iPS cells. We also studied the molecular mechanism downstream of NAMPT/SIRTs in iPS cells. Results: We demonstrated that NAMPT is indispensable for the maintenance, survival and hematopoietic differentiation of induced pluripotent stem (iPS) cells. We found that inhibition of NAMPT or SIRT2 in iPS cells induces p53 protein by promoting its lysine acetylation. This leads to activation of the p53 target, p21, with subsequent cell cycle arrest and induction of apoptosis in iPS cells. NAMPT and SIRT2 inhibition also affects hematopoietic differentiation of iPS cells in an embryoid body (EB)-based cell culture system. Conclusions: Our data demonstrate the essential role of the NAMPT/SIRT2/p53/p21 signaling axis in the maintenance and hematopoietic differentiation of iPS cells.

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NAMPT/SIRT2–mediated inhibition of the p53-p21 signaling pathway is indispensable for maintenance and hematopoietic differentiation of human iPS cells

10.21203/rs.3.rs-22092/v2 ◽

2020 ◽

Author(s):

Yun Xu ◽

Masoud Nasri ◽

Benjamin Dannenmann ◽

Perihan Mir ◽

Azadeh Zahabi ◽

...

Keyword(s):

Embryoid Body ◽

P53 Protein ◽

Ips Cells ◽

Hematopoietic Differentiation ◽

Cellular Functions ◽

Nicotinamide Phosphoribosyltransferase ◽

Signaling Axis ◽

Human Ips Cells ◽

Induced Pluripotent

Abstract Background: Nicotinamide phosphoribosyltransferase (NAMPT) regulates cellular functions through the protein deacetylation activity of nicotinamide adenine dinucleotide (NAD+)-dependent sirtuins (SIRTs). SIRTs regulate functions of histones and none-histone proteins. The role of NAMPT/SIRTs pathway in the regulation of maintenance and differentiation of human induced pluripotent stem (iPS) cells is not fully elucidated.Methods: We evaluated the effects of specific inhibitors of NAMPT-, or SIRT2 on the pluripotency, proliferation, survival and hematopoietic differentiation of human iPS cells. We also studied the molecular mechanism downstream of NAMPT/SIRTs in iPS cells.Results: We demonstrated that NAMPT is indispensable for the maintenance, survival and hematopoietic differentiation of induced pluripotent stem (iPS) cells. We found that inhibition of NAMPT or SIRT2 in iPS cells induces p53 protein by promoting its lysine acetylation. This leads to activation of the p53 target, p21, with subsequent cell cycle arrest and induction of apoptosis in iPS cells. NAMPT and SIRT2 inhibition also affect hematopoietic differentiation of iPS cells in an embryoid body (EB)-based cell culture system.Conclusions: Our data demonstrate the essential role of the NAMPT/SIRT2/p53/p21 signaling axis in the maintenance and hematopoietic differentiation of iPS cells.

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Hypothalamic contribution to pituitary functions is recapitulated in vitro using 3D-cultured human iPS cells

Yearbook of Paediatric Endocrinology ◽

10.1530/ey.17.1.5 ◽

2020 ◽

Author(s):

Kasai T ◽

Suga H ◽

Sakakibara ◽

Ozone C ◽

Matsumoto R ◽

...

Keyword(s):

Ips Cells ◽

Human Ips Cells

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