title: Characterization of stimulus-secretion coupling in the human pancreatic EndoC-βH1 beta cell line.
abstract: OBJECTIVE
  Studies on beta cell metabolism are often conducted in rodent beta cell lines due to the lack of stable human beta cell lines. Recently, a human cell line, EndoC-βH1, was generated. Here we investigate stimulus-secretion coupling in this cell line, and compare it with that in the rat beta cell line, INS-1 832/13, and human islets.
  
  
  METHODS
  Cells were exposed to glucose and pyruvate. Insulin secretion and content (radioimmunoassay), gene expression (Gene Chip array), metabolite levels (GC/MS), respiration (Seahorse XF24 Extracellular Flux Analyzer), glucose utilization (radiometric), lactate release (enzymatic colorimetric), ATP levels (enzymatic bioluminescence) and plasma membrane potential and cytoplasmic Ca2+ responses (microfluorometry) were measured. Metabolite levels, respiration and insulin secretion were examined in human islets.
  
  
  RESULTS
  Glucose increased insulin release, glucose utilization, raised ATP production and respiratory rates in both lines, and pyruvate increased insulin secretion and respiration. EndoC-βH1 cells exhibited higher insulin secretion, while plasma membrane depolarization was attenuated, and neither glucose nor pyruvate induced oscillations in intracellular calcium concentration or plasma membrane potential. Metabolite profiling revealed that glycolytic and TCA-cycle intermediate levels increased in response to glucose in both cell lines, but responses were weaker in EndoC-βH1 cells, similar to those observed in human islets. Respiration in EndoC-βH1 cells was more similar to that in human islets than in INS-1 832/13 cells.
  
  
  CONCLUSIONS
  Functions associated with early stimulus-secretion coupling, with the exception of plasma membrane potential and Ca2+ oscillations, were similar in the two cell lines; insulin secretion, respiration and metabolite responses were similar in EndoC-βH1 cells and human islets. While both cell lines are suitable in vitro models, with the caveat of replicating key findings in isolated islets, EndoC-βH1 cells have the advantage of carrying the human genome, allowing studies of human genetic variants, epigenetics and regulatory RNA molecules.
authors: Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, CRC, Malmö, Sweden.
authors: Lotta E
authors: LE
authors: Andersson
authors: Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, CRC, Malmö, Sweden.
authors: Bérengère
authors: B
authors: Valtat
authors: Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, CRC, Malmö, Sweden.
authors: Annika
authors: A
authors: Bagge
authors: Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, CRC, Malmö, Sweden.
authors: Vladimir V
authors: VV
authors: Sharoyko
authors: Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, CRC, Malmö, Sweden; Buck Institute for Research on Aging, Novato, California, United States of America.
authors: David G
authors: DG
authors: Nicholls
authors: Université Pierre et Marie Curie-Paris 6, Biotechnology and Biotherapy Team, Centre de Recherche de I'Institut du Cerveau et de la Moelle épiniére (CRICM), UMRS 975, Paris, France.
authors: Philippe
authors: P
authors: Ravassard
authors: INSERM U1016, Cochin Institute, Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Faculty Cochin, Paris, France.
authors: Raphael
authors: R
authors: Scharfmann
authors: Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, CRC, Malmö, Sweden.
authors: Peter
authors: P
authors: Spégel
authors: Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, CRC, Malmö, Sweden.
authors: Hindrik
authors: H
authors: Mulder
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D049109:Cell Proliferation; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D050417:Insulin-Secreting Cells / Q000166:cytology* / Q000378:metabolism*; D008564:Membrane Potentials; D055442:Metabolome; D010101:Oxygen Consumption
chemical_list: D007328:Insulin; D000255:Adenosine Triphosphate; D005947:Glucose; D002118:Calcium