1. NGF-withdrawal induces apoptosis in pancreatic beta cells in vitro
- Author
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Donatella Pastore, Francesca Ferrelli, Renato Lauro, Frédéric Ris, Philippe A. Halban, Jose Oberholzer, Daniela Pierucci, S. Cicconi, Claudia Matteucci, Lionel N.J.L. Marlier, P. Borboni, Massimo Federici, Piero Marchetti, F. Cozzolino, Paolo Bonini, and Lorella Marselli
- Subjects
MAPK/ERK pathway ,Male ,Nucleosomes/ultrastructure ,MAP Kinase Kinase 4 ,Endocrinology, Diabetes and Metabolism ,Bcl-X Protein ,Fluorescent Antibody Technique ,Gene Expression ,Carrier Proteins/metabolism ,Apoptosis ,Mitogen-activated protein kinase kinase ,PC12 Cells ,Receptor, Nerve Growth Factor ,Phosphatidylserines/metabolism ,Receptor, trkA/analysis/genetics ,Mice ,Phosphatidylinositol 3-Kinases ,Nerve Growth Factor ,Phosphorylation ,Nerve Growth Factor/genetics/immunology/ physiology ,Cells, Cultured ,ddc:616 ,Reverse Transcriptase Polymerase Chain Reaction ,RNA, Messenger/analysis ,Antibodies, Monoclonal ,Middle Aged ,Protein-Serine-Threonine Kinases ,Flow Cytometry ,Nucleosomes ,medicine.anatomical_structure ,Proto-Oncogene Proteins c-bcl-2 ,Bcl-Associated Death Protein ,bcl-Associated Death Protein ,Proto-Oncogene Proteins c-bcl-2/metabolism ,Signal transduction ,Beta cell ,Signal Transduction ,Mitogen-Activated Protein Kinase Kinases/metabolism ,Islets of Langerhans/ cytology/ metabolism ,bcl-X Protein ,Mice, Transgenic ,DNA Fragmentation ,Phosphatidylserines ,Receptors, Nerve Growth Factor ,Biology ,Protein Serine-Threonine Kinases ,Cell Line ,Islets of Langerhans ,Proto-Oncogene Proteins ,Internal Medicine ,medicine ,Animals ,Humans ,RNA, Messenger ,Receptor, trkA ,Autocrine signalling ,Protein kinase B ,Mitogen-Activated Protein Kinase Kinases ,Pancreatic islets ,JNK Mitogen-Activated Protein Kinases ,Receptors, Nerve Growth Factor/analysis/genetics ,Proto-Oncogene Proteins/metabolism ,Antibodies, Monoclonal/pharmacology ,Coculture Techniques ,Rats ,Enzyme Activation ,Nerve growth factor ,nervous system ,Cancer research ,Carrier Proteins ,Proto-Oncogene Proteins c-akt - Abstract
AIMS/HYPOTHESIS: Using primary cultures of human pancreatic islets, purified human pancreatic beta cells and the mouse beta TC6-F7 cell line, we analysed the expression of nerve growth factor, (NGF/NGF) receptors in beta cells. To investigate whether NGF could sub-serve an autocrine antiapoptotic role in beta cells, we studied the effects of NGF withdrawal using a neutralizing monoclonal anti-NGF antibody. METHODS: The expression of NGF and NGF receptors (gp140(Trk-A) and p75(NTR)) were analysed by RT-PCR and immunofluorescence. Pulse-chase experiments and beta cell/PC12 co-cultures were used to investigate NGF production and secretion from beta cells. Possible apoptosis induced by NGF withdrawal was monitored by phosphatidylserine translocation, nucleosomal formation, DNA laddering and FACS analysis. Involvement of transcription/translation mechanisms were investigated as well as the gp140(Trk-A) required. Finally, signal transduction pathways typically involved in apoptotic mechanisms were analysed by western blot analysis. RESULTS: We show that NGF and both NGF receptors, gp140(Trk-A) and p75(NTR) are expressed in beta cells where NGF is produced and secreted in a biologically active form. NGF-withdrawal induces beta-cell transcription/translation independent apoptosis but mediated by gp140(Trk-A). Analysis of signal transduction pathways revealed that NGF withdrawal inhibits the PI3-K, protein kinase B (AKT), Bad survival pathway and activates c-Jun kinase (JNK) whereas ERKs and p38 mitogen-activated protein kinase (MAPK) are not affected. Moreover, Bcl-XL, but not Bcl-2 protein expression are reduced. CONCLUSION/INTERPRETATION: We suggest that the integrity of the NGF/NGF receptor system and NGF bioavailability participate in controlling beta-cell survival in culture which represents a key issue for improving possibilities for transplantations in the treatment of diabetes.
- Published
- 2001