Increased expression of calbindin D28k via herpes simplex virus amplicon vector decreases calcium ion mobilization and enhances neuronal survival after hypoglycemic challenge.
Disruption of Ca2+ homeostasis often leads to neuron death. Recently, the function of calcium-binding proteins as neuronal Ca2+ buffers has been debated. We tested whether calbindin D28k functions as an intracellular Ca2+ buffer by constructing bicistronic herpes simplex virus vectors to deliver rat calbindin cDNA to hippocampal neurons in vitro. Neurons were infected with vectors delivering calbindin or a negative control or were mock-infected. After 12 or 24 h of hypoglycemia, infected cells were made aglycemic during fura-2 calcium ratiometric imaging. In response to this challenge, neuronal overexpressing calbindin had less Ca2+ mobilized as compared with negative controls or mock-infected cells. Cells were assayed for survival after 12- or 24-h hypoglycemia or aglycemia. The calbindin vector decreased neuronal death due to hypoglycemia but not aglycemia. Here we demonstrate, in response to hypoglycemic challenge, both decreased Ca2+ mobilization and increased survival of cells infected with the calbindin vector.
Meier
T J
TJ
Department of Biological Sciences, Stanford University, California 94305-5020, U.S.A.
Ho
D Y
DY
Sapolsky
R M
RM
D000818:Animals; D064092:Calbindin 1; D064026:Calbindins; D002118:Calcium / Q000378:metabolism*; D002470:Cell Survival; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D003470:Culture Media; D005333:Fetus; D019084:Fluorescent Antibody Technique, Indirect; D016257:Fura-2; D005822:Genetic Vectors; D005947:Glucose / Q000494:pharmacology*; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D007003:Hypoglycemia; D007700:Kinetics; D009474:Neurons / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D010957:Plasmids; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000096:biosynthesis; D064030:S100 Calcium Binding Protein G / Q000096:biosynthesis*; D018139:Simplexvirus; D014162:Transfection; D014709:Vero Cells
C576500:Calb1 protein, rat; D064092:Calbindin 1; D064026:Calbindins; D003470:Culture Media; D011994:Recombinant Proteins; D064030:S100 Calcium Binding Protein G; D005947:Glucose; D002118:Calcium; D016257:Fura-2