Triptolide induces apoptosis through the SERCA 3 upregulation in PC12 cells.
Diterpenoid triepoxide - Triptolide (TTL) - increased protein levels of the noradrenaline transporter in three pheochromocytoma cell lines. This transporter is involved in the apoptosis induction through the inhibition of a transcription factor NF-kappa B. Nevertheless, calcium release from the endoplasmic reticulum can also induce inner mitochondrial pathway of apoptosis in variety of cells. Therefore, the aim of this work was to evaluate an involvement of calcium and, more specifically, the intracellular calcium transport systems in the apoptosis induction in pheochrocytoma cell line PC12. We observed significantly increased amount of reticular calcium in TTL-treated cells compared to control, untreated cells. Surprisingly, gene expression of the IP3 receptors was not changed after the TTL treatment, but ryanodine receptor of the type 2 (RyR2) was downregulated and sarco/endoplasmic reticulum calcium ATPase type 3 (SERCA 3) was upregulated in TTL- treated cells, compared to untreated controls. SERCA 3 blocking with the specific blocker thapsigargin prevented increase in apoptosis observed by the TTL treatment. Decrease in the ATP production by a replacement of glucose in the cultivation medium for its nonutilizable analog 2-deoxyglucose also prevented induction of the apoptosis in TTL-treated PC12 cells. Thus, these results suggest that upregulation of the SERCA 3 is ultimately involved in the TTL-induced apoptosis in PC12 cells.
Institute of Molecular Physiology and Genetics, Center of Excellence for Studying Metabolic Aspects of Development, Diagnostics and Treatment of the Oncologic Diseases, Slovak Academy of Sciences, Bratislava, Slovak Republic. sona.hudecova@savba.sk.
Olga
O
Krizanova
Jana
J
Markova
Karel
K
Pacak
Ludovit
L
Skultety
Andrea
A
Soltysova
Sona
S
Hudecova
D000255:Adenosine Triphosphate / Q000737:chemistry; D000818:Animals; D017209:Apoptosis; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D004224:Diterpenes / Q000737:chemistry*; D004852:Epoxy Compounds / Q000737:chemistry; D015972:Gene Expression Regulation, Neoplastic; D047028:Macrocyclic Compounds / Q000737:chemistry; D008856:Microscopy, Fluorescence; D016328:NF-kappa B / Q000378:metabolism; D009638:Norepinephrine / Q000737:chemistry; D020411:Oligonucleotide Array Sequence Analysis; D010080:Oxazoles / Q000737:chemistry; D016716:PC12 Cells; D010616:Phenanthrenes / Q000737:chemistry*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051381:Rats; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000378:metabolism*; D019284:Thapsigargin / Q000737:chemistry
C506951:Atp2a3 protein, rat; D004224:Diterpenes; D004852:Epoxy Compounds; D047028:Macrocyclic Compounds; D016328:NF-kappa B; D010080:Oxazoles; D010616:Phenanthrenes; D019837:Ryanodine Receptor Calcium Release Channel; C108644:xestospongin A; C001899:triptolide; D019284:Thapsigargin; D000255:Adenosine Triphosphate; D019869:Phosphatidylinositol 3-Kinases; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D002118:Calcium; D009638:Norepinephrine