Mitochondrial Depolarization Accompanies Cytochrome cRelease During Apoptosis in PC6 Cells

Heiskanen, Kaisa M.; Bhat, Manjunatha B.; Wang, Hsing-Wen; Ma, Jianjie; Nieminen, Anna‐Liisa

doi:10.1074/jbc.274.9.5654

Cited by 325 publications

(245 citation statements)

References 31 publications

Supporting

Mentioning

232

Contrasting

Order By: Relevance

“…Chromatin condensation started at 45 min and fragmentation at 60 min post-PDT, and apoptotic cells continued to show the diffuse cytochrome c staining pattern. At later times, the staining of cytochrome c became very weak (not shown), probably because the protein leaked out of the cells (Heiskanen et al, 1999). The majority of the cells that received the higher dose of PDT (300 nM Pc 4 and 120 mJ/cm 2 red light) also released cytochrome c from mitochondria at 15 min (data not shown).…”

Section: Resultsmentioning

confidence: 94%

Dissociation of mitochondrial depolarization from cytochrome c release during apoptosis induced by photodynamic therapy

2001

View full text Add to dashboard Cite

Photodynamic therapy (PDT) with the phthalocyanine photosensitizer Pc 4 induces rapid apoptosis in mouse lymphoma (LY-R) cells, initiating with the release of cytochrome c from mitochondria. It has been proposed that the opening of the mitochondrial membrane permeability transition pores, which results in the dissipation of the mitochondrial membrane potential (Δψ m ), is essential for the escape of cytochrome c from mitochondria into the cytosol as well as for apoptotic cell death. Therefore, we have assessed the correlation between the loss of Δψ m and the release of cytochrome c following PDT. Treatment of LY-R cells with 300 nM Pc 4 and 60, 90 or 120 mJ/cm 2 of red light resulted in apoptosis of 80–90% of the cells, accompanied by >20-fold elevation in caspase-3-like activity within one h. At all 3 doses of PDT employed here, the majority of the cytochrome c was released from mitochondria at 15 min after irradiation, as determined by an immunohistochemical method. In contrast, the loss of Δψ m following PDT, as monitored by the uptake of JC-1 or Rh-123, depended on the PDT dose and the post-treatment time. In spite of the release of cytochrome c at 15 min after each of the 3 doses, a corresponding loss of Δψ m was observed only for those cells that received the highest dose of PDT. Virtually all cells that received one of the lower doses of PDT (300 nM Pc 4 plus 60 or 90 mJ/cm 2 ) maintained normal Δψ m . Hence, our results support the conclusion that the release of cytochrome c from mitochondria resulting from Pc 4-PDT-induced photodamage is independent of the loss of Δψ m . Therefore, it is important to consider a range of doses of this or other apoptotic stimuli in deciphering the relationship of metabolic responses that contribute to apoptosis. © 2001 Cancer Research Campaign http://www.bjcancer.com

show abstract

Section: Resultsmentioning

confidence: 94%

Dissociation of mitochondrial depolarization from cytochrome c release during apoptosis induced by photodynamic therapy

2001

View full text Add to dashboard Cite

show abstract

“…33 In Z138 cells, loss of DcM was detected in TRAIL-treated cells (Figure 4a) and correlated with the cell death response (Figure 2i). To further examine the response of glucose (À) cells to mitochondrialdependent apoptosis, we treated Z138 cells with ABT-737 34 and ionising radiation.…”

Section: Dg Inhibits Glycolysis and Sensitises Z138 Cells To Trail-imentioning

confidence: 85%

Switching from aerobic glycolysis to oxidative phosphorylation modulates the sensitivity of mantle cell lymphoma cells to TRAIL

et al. 2012

View full text Add to dashboard Cite

TRAIL (TNF (tumour necrosis factor)-related apoptosis-inducing ligand) a putative anti-cancer cytokine induces apoptosis through DISC (death-inducing signalling complex)-mediated activation of caspase-8 and/or cleavage of Bid. TRAIL is relatively specific for tumour cells but primary chronic lymphocytic leukaemia and mantle cell lymphoma (MCL) cells are resistant. Herein, we show that cellular metabolism influences cell death and that MCL cells (Z138 cell line) can survive/proliferate in glucose-free media by switching from aerobic glycolysis to 'coupled' oxidative phosphorylation. Extracellular flux analysis and mitochondrial inhibitors reveal that in the absence of glycolysis, Z138 cells have enhanced respiratory capacity coupled to ATP synthesis, similar to 'classical' state 3 mitochondria. Conversely, 2-deoxyglucose (2DG) blocked glycolysis and partially inhibited glycolyticdependent oxidative phosphorylation, resulting in a 50% reduction in cellular ATP levels. Also, 2DG sensitised Z138 cells to TRAIL and induced a marked decrease in caspase-8, -3, cFLIP S , Bid and Mcl-1 expression but Bak remained unchanged, altering the Mcl-1/Bak ratio, facilitating cytochrome c release and cell death. Conversely, under glucose-free conditions, Z138 cells were less sensitive to TRAIL with reduced TRAIL-R1/R2 surface receptor expression and impaired DISC formation. Anti-apoptotic proteins Bcl-2 and XIAP were up-regulated while pro-apoptotic BAX was down-regulated. Additionally, mitochondria had higher levels of cytochrome c and ultrastucturally exhibited a condensed configuration with enhanced intracristal spaces. Thus, metabolic switching was accompanied by mitochondrial proteome and ultrastructural remodelling enabling enhanced respiration activity. Cytochrome c release was decreased in glucose-free cells, suggesting that either pore formation was inhibited or that cytochrome c was more tightly bound. Glucose-free Z138 cells were also resistant to intrinsic cell death stimuli (ABT-737 and ionising radiation). In summary, in MCL cells, the anti-glycolytic effects of 2DG and glucose restriction produced opposite effects on TRAIL-induced cell death, demonstrating that mitochondrial metabolism directly modulates sensitivity of tumour cells to apoptosis.

show abstract

“…When stably expressed in cells, cytochrome c fused to green fluorescent protein (cyt c-GFP) has been shown to behave similarly to endogenous cytochrome c (4,6). It localizes predominantly to the mitochondria and is released when the cells are treated with a proapoptotic stimulus to assume a diffuse cytosolic pattern.…”

Section: Visualizing Cytochrome C Releasementioning

confidence: 99%

Measuring apoptosis at the single cell level

Bouchier‐Hayes

Muñoz-Pinedo

Connell

et al. 2008

Methods

View full text Add to dashboard Cite

The use of live cell microscopy has made a number of contributions to the study of apoptosis. Many of the tools and techniques are available that allow us to image the key events that occur during cell death including mitochondrial outer membrane permeabilization, mitochondrial transmembrane potential changes, translocation of Bcl-2 family members, caspase activation, phosphatidylserine flip and plasma membrane rupture. We discuss these techniques here and highlight the advantages and drawbacks of using such approaches to study apoptosis.

show abstract

Mitochondrial Depolarization Accompanies Cytochrome cRelease During Apoptosis in PC6 Cells

Cited by 325 publications

References 31 publications

Dissociation of mitochondrial depolarization from cytochrome c release during apoptosis induced by photodynamic therapy

Dissociation of mitochondrial depolarization from cytochrome c release during apoptosis induced by photodynamic therapy

Switching from aerobic glycolysis to oxidative phosphorylation modulates the sensitivity of mantle cell lymphoma cells to TRAIL

Measuring apoptosis at the single cell level

Contact Info

Product

Resources

About