Inhibitory effects of 1,25-dihydroxyvitamin D3 and its low-calcemic analogues on staurosporine-induced apoptosis.
The active form of vitamin D3 and some of its related compounds show neuroprotective effects in various models of neuronal damage, however, mechanism of their anti-apoptotic action has not been elucidated. Therefore, the present study was designed to investigate the effects of 1,25-dihydroxyvitamin D3 and its low-calcemic analogues, PRI-2191, PRI-1890 and PRI-1901 on staurosporine-induced apoptosis in human neuroblastoma SH-SY5Y cells. Twenty-four hour incubation with staurosporine (1 microM) enhanced the caspase-3 activity, decreased mitochondrial membrane potential and increased the number of apoptotic cells as visualized by Hoechst staining. 1,25-Dihydroxyvitamin D3 and PRI-2191 attenuated the staurosporine-induced caspase-3 activity at 5, 50 and 500 nM, whereas PRI-1890 and PRI-1901 were active only at higher concentrations. Furthermore, 1,25-dihydroxyvitamin D3 (50 and 500 nM) and PRI-2191 (500 but not 50 nM) reversed the staurosporine-evoked decrease in mitochondrial membrane potential. Hoechst and calcein staining confirmed the neuroprotective effects of the secosteroids under study. Further study revealed that a selective inhibitor of phosphatidylinositol 3-kinase (PI3-K), wortmannin, at concentration of 100 nM antagonized the effect of 1,25-dihydroxyvitamin D3 and PRI-2191 on staurosporine-induced caspase-3 activation. These data indicate that 1,25-dihydroxyvitamin D3 and its low-calcemic analogues at nanomolar concentrations inhibited mitochondrial pathway of apoptosis in SH-SY5Y neuronal cells, though with different potency. Moreover, the activation of PI3-K/Akt signaling pathway appears to play a role in anti-apoptotic effects of the secosteroids.
Regulska
Magdalena
M
Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, PL 31-343 Kraków, Poland.
Leśkiewicz
Monika
M
Budziszewska
Bogusława
B
Kutner
Andrzej
A
Jantas
Danuta
D
Basta-Kaim
Agnieszka
A
Kubera
Marta
M
Jaworska-Feil
Lucylla
L
Lasoń
Władysław
W
D000730:Androstadienes / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D002117:Calcitriol / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology*; D053148:Caspase 3 / Q000378:metabolism; D061945:Caspase Inhibitors; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004100:Dihydroxycholecalciferols / Q000737:chemistry / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D009842:Oligopeptides / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012632:Secosteroids / Q000737:chemistry / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D019311:Staurosporine / Q000494:pharmacology*; D013997:Time Factors; D000077191:Wortmannin
D000730:Androstadienes; D002117:Calcitriol; D053148:Caspase 3; D061945:Caspase Inhibitors; D004100:Dihydroxycholecalciferols; D009842:Oligopeptides; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012632:Secosteroids; D019311:Staurosporine; D000077191:Wortmannin; C108254:PRI 1901; C099158:acetyl-aspartyl-glutamyl-valyl-aspartal; C023850:1 alpha,24-dihydroxyvitamin D3