Limits...
Poly(ADP-ribosyl)ation of p53 contributes to TPEN-induced neuronal apoptosis.

Kim HL, Ra H, Kim KR, Lee JM, Im H, Kim YH - Mol. Cells (2015)

Bottom Line: Poly(ADP-ribosyl)ation of p53 occurred starting 1 h after TPEN treatment.Consistent with this, the induction of downstream proapoptotic proteins PUMA and NOXA was noticeably reduced by chemical inhibitors or genetic deletion of PARP-1.Taken together, these findings indicate that PARP-1 is essential for TPEN-induced neuronal apoptosis.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Biology, Sejong University, Seoul 143-747, Korea.

ABSTRACT
Depletion of intracellular zinc by N,N,N',N'-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN) induces p53-mediated protein synthesis-dependent apoptosis of mouse cortical neurons. Here, we examined the requirement for poly(ADP-ribose) polymerase (PARP)-1 as an upstream regulator of p53 in zinc depletion-induced neuronal apoptosis. First, we found that chemical inhibition or genetic deletion of PARP-1 markedly attenuated TPEN-induced apoptosis of cultured mouse cortical neurons. Poly(ADP-ribosyl)ation of p53 occurred starting 1 h after TPEN treatment. Suggesting the critical role of PARP-1, the TPEN-induced increase of stability and activity of p53 as well as poly(ADP-ribosyl)ation of p53 was almost completely blocked by PARP inhibition. Consistent with this, the induction of downstream proapoptotic proteins PUMA and NOXA was noticeably reduced by chemical inhibitors or genetic deletion of PARP-1. TPEN-induced cytochrome C release into the cytosol and caspase-3 activation were also blocked by inhibition of PARP-1. Taken together, these findings indicate that PARP-1 is essential for TPEN-induced neuronal apoptosis.

No MeSH data available.


Related in: MedlinePlus

Essential role of PARP-1 as an upstream regulator of TPEN-induced neuronal apoptosis. (A) Confocal photomicrographs of cortical neuron cultures showing the translocation of cytochrome C from mitochondria to the cytosol after TPEN treatment. NAM blocked this TPEN-induced release of cyto-chrome C into the cytosol. Scale bar = 50 μm. Arrows and arrowheads denote cytochrome C release and DNA fragmentation, respectively. (B, C) Western blot analysis (B) or enzymatic activity (C, n = 4 cultures) of caspase-3 in TPEN-induced neuronal apoptosis. Protein samples were prepared after 12-h exposure to sham wash (CTRL) or TPEN with or without NAM or AB. *p < 0.05 vs. TPEN alone, ANOVA. (D, E) Western blot analysis (D) or enzymatic activity (E, n = 4 cultures) of caspase-3 in PARP-1+/+ or PARP-1−/−mouse cortical neuron cultures after 18-h exposure to sham wash (CTRL) or TPEN. *p < 0.05 vs. sham wash control, ANOVA.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4400305&req=5

f4-molce-38-4-312: Essential role of PARP-1 as an upstream regulator of TPEN-induced neuronal apoptosis. (A) Confocal photomicrographs of cortical neuron cultures showing the translocation of cytochrome C from mitochondria to the cytosol after TPEN treatment. NAM blocked this TPEN-induced release of cyto-chrome C into the cytosol. Scale bar = 50 μm. Arrows and arrowheads denote cytochrome C release and DNA fragmentation, respectively. (B, C) Western blot analysis (B) or enzymatic activity (C, n = 4 cultures) of caspase-3 in TPEN-induced neuronal apoptosis. Protein samples were prepared after 12-h exposure to sham wash (CTRL) or TPEN with or without NAM or AB. *p < 0.05 vs. TPEN alone, ANOVA. (D, E) Western blot analysis (D) or enzymatic activity (E, n = 4 cultures) of caspase-3 in PARP-1+/+ or PARP-1−/−mouse cortical neuron cultures after 18-h exposure to sham wash (CTRL) or TPEN. *p < 0.05 vs. sham wash control, ANOVA.

Mentions: Next, we investigated the effects of PARP-1 on downstream events of TPEN-induced apoptosis, including cytochrome C release and caspase-3 activation. TPEN-induced cytochrome C release from mitochondria to the cytosol and nuclear condensation were completely blocked by the PARP inhibitor NAM (Fig. 4A). TPEN-induced caspase-3 activation was also blocked by chemical inhibitors (Figs. 4B–4C) or genetic deletion of PARP-1 (Figs. 4D–4E). Thus, PARP-1 appears to act as an upstream regulator of TPEN-induced neuronal apoptosis.


Poly(ADP-ribosyl)ation of p53 contributes to TPEN-induced neuronal apoptosis.

Kim HL, Ra H, Kim KR, Lee JM, Im H, Kim YH - Mol. Cells (2015)

Essential role of PARP-1 as an upstream regulator of TPEN-induced neuronal apoptosis. (A) Confocal photomicrographs of cortical neuron cultures showing the translocation of cytochrome C from mitochondria to the cytosol after TPEN treatment. NAM blocked this TPEN-induced release of cyto-chrome C into the cytosol. Scale bar = 50 μm. Arrows and arrowheads denote cytochrome C release and DNA fragmentation, respectively. (B, C) Western blot analysis (B) or enzymatic activity (C, n = 4 cultures) of caspase-3 in TPEN-induced neuronal apoptosis. Protein samples were prepared after 12-h exposure to sham wash (CTRL) or TPEN with or without NAM or AB. *p < 0.05 vs. TPEN alone, ANOVA. (D, E) Western blot analysis (D) or enzymatic activity (E, n = 4 cultures) of caspase-3 in PARP-1+/+ or PARP-1−/−mouse cortical neuron cultures after 18-h exposure to sham wash (CTRL) or TPEN. *p < 0.05 vs. sham wash control, ANOVA.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4400305&req=5

f4-molce-38-4-312: Essential role of PARP-1 as an upstream regulator of TPEN-induced neuronal apoptosis. (A) Confocal photomicrographs of cortical neuron cultures showing the translocation of cytochrome C from mitochondria to the cytosol after TPEN treatment. NAM blocked this TPEN-induced release of cyto-chrome C into the cytosol. Scale bar = 50 μm. Arrows and arrowheads denote cytochrome C release and DNA fragmentation, respectively. (B, C) Western blot analysis (B) or enzymatic activity (C, n = 4 cultures) of caspase-3 in TPEN-induced neuronal apoptosis. Protein samples were prepared after 12-h exposure to sham wash (CTRL) or TPEN with or without NAM or AB. *p < 0.05 vs. TPEN alone, ANOVA. (D, E) Western blot analysis (D) or enzymatic activity (E, n = 4 cultures) of caspase-3 in PARP-1+/+ or PARP-1−/−mouse cortical neuron cultures after 18-h exposure to sham wash (CTRL) or TPEN. *p < 0.05 vs. sham wash control, ANOVA.
Mentions: Next, we investigated the effects of PARP-1 on downstream events of TPEN-induced apoptosis, including cytochrome C release and caspase-3 activation. TPEN-induced cytochrome C release from mitochondria to the cytosol and nuclear condensation were completely blocked by the PARP inhibitor NAM (Fig. 4A). TPEN-induced caspase-3 activation was also blocked by chemical inhibitors (Figs. 4B–4C) or genetic deletion of PARP-1 (Figs. 4D–4E). Thus, PARP-1 appears to act as an upstream regulator of TPEN-induced neuronal apoptosis.

Bottom Line: Poly(ADP-ribosyl)ation of p53 occurred starting 1 h after TPEN treatment.Consistent with this, the induction of downstream proapoptotic proteins PUMA and NOXA was noticeably reduced by chemical inhibitors or genetic deletion of PARP-1.Taken together, these findings indicate that PARP-1 is essential for TPEN-induced neuronal apoptosis.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Biology, Sejong University, Seoul 143-747, Korea.

ABSTRACT
Depletion of intracellular zinc by N,N,N',N'-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN) induces p53-mediated protein synthesis-dependent apoptosis of mouse cortical neurons. Here, we examined the requirement for poly(ADP-ribose) polymerase (PARP)-1 as an upstream regulator of p53 in zinc depletion-induced neuronal apoptosis. First, we found that chemical inhibition or genetic deletion of PARP-1 markedly attenuated TPEN-induced apoptosis of cultured mouse cortical neurons. Poly(ADP-ribosyl)ation of p53 occurred starting 1 h after TPEN treatment. Suggesting the critical role of PARP-1, the TPEN-induced increase of stability and activity of p53 as well as poly(ADP-ribosyl)ation of p53 was almost completely blocked by PARP inhibition. Consistent with this, the induction of downstream proapoptotic proteins PUMA and NOXA was noticeably reduced by chemical inhibitors or genetic deletion of PARP-1. TPEN-induced cytochrome C release into the cytosol and caspase-3 activation were also blocked by inhibition of PARP-1. Taken together, these findings indicate that PARP-1 is essential for TPEN-induced neuronal apoptosis.

No MeSH data available.


Related in: MedlinePlus