The roles of caspase-3 and bcl-2 in chemically-induced apoptosis but not necrosis of renal epithelial cells

AbstractActivation of the apoptotic pathway is a major cause of progressive loss of function in chronic diseases such as neurodegenerative and diabetic kidney diseases. There is an unmet need for an anti-apoptotic drug that acts in the early stage of the apoptotic process. The multifunctional protein Na+,K+-ATPase has, in addition to its role as a transporter, a signaling function that is activated by its ligand, the cardiotonic steroid ouabain. Several lines of evidence suggest that sub-saturating concentrations of ouabain protect against apoptosis of renal epithelial cells, a common complication and major cause of death in diabetic patients. Here, we induced apoptosis in primary rat renal epithelial cells by exposing them to an elevated glucose concentration (20 mM) and visualized the early steps in the apoptotic process using super-resolution microscopy. Treatment with 10 nM ouabain interfered with the onset of the apoptotic process by inhibiting the activation of the BH3-only protein Bad and its translocation to mitochondria. This occurred before the pro-apoptotic protein Bax had been recruited to mitochondria. Two ouabain regulated and Akt activating Ca2+/calmodulin-dependent kinases were found to play an essential role in the ouabain anti-apoptotic effect. Our results set the stage for further exploration of ouabain as an anti-apoptotic drug in diabetic kidney disease as well as in other chronic diseases associated with excessive apoptosis.

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EGFR-dependent ERK activation triggers hydrogen peroxide-induced apoptosis in OK renal epithelial cells

Archives of Toxicology ◽

10.1007/s00204-005-0052-2 ◽

2005 ◽

Vol 80 (6) ◽

pp. 337-346 ◽

Cited By ~ 25

Author(s):

Ju Suk Lee ◽

Su Yung Kim ◽

Chae Hwa Kwon ◽

Yong Keun Kim

Keyword(s):

Hydrogen Peroxide ◽

Epithelial Cells ◽

Erk Activation ◽

Renal Epithelial Cells ◽

Induced Apoptosis

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Involvement of endoplasmic reticulum stress-activated PERK-eIF2α-ATF4 signaling pathway in T-2 toxin-induced apoptosis of porcine renal epithelial cells

Toxicology and Applied Pharmacology ◽

10.1016/j.taap.2021.115753 ◽

2021 ◽

pp. 115753

Author(s):

Xiangyan Liu ◽

Ze Wang ◽

Xianglin Wang ◽

Xiaona Yan ◽

Qing He ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Epithelial Cells ◽

Endoplasmic Reticulum Stress ◽

Signaling Pathway ◽

Renal Epithelial Cells ◽

Induced Apoptosis

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ERK promotes hydrogen peroxide-induced apoptosis through caspase-3 activation and inhibition of Akt in renal epithelial cells

AJP Renal Physiology ◽

10.1152/ajprenal.00170.2006 ◽

2007 ◽

Vol 292 (1) ◽

pp. F440-F447 ◽

Cited By ~ 100

Author(s):

Shougang Zhuang ◽

Yan Yan ◽

Rebecca A. Daubert ◽

Jiahuai Han ◽

Rick G. Schnellmann

Keyword(s):

Hydrogen Peroxide ◽

Epithelial Cells ◽

Caspase 3 ◽

Ischemia Reperfusion ◽

Nuclear Condensation ◽

Histone H2b ◽

Adenoviral Infection ◽

Akt Phosphorylation ◽

Renal Proximal Tubular Cells ◽

Induced Apoptosis

Reactive oxygen species, including hydrogen peroxide (H2O2), are generated during ischemia-reperfusion and are critically involved in acute renal failure. The present studies examined the role of the extracellular signal-regulated kinase (ERK) pathway in H2O2-induced renal proximal tubular cells (RPTC) apoptosis. Exposure of RPTC to 1 mM H2O2resulted in apoptosis and activation of ERK1/2 and Akt. Pretreatment with the specific MEK inhibitors, U0126 and PD98059, or adenoviral infection with a construct that encodes a negative mutant of MEK1, protected cells against H2O2-induced apoptosis. In contrast, expression of constitutively active MEK1 enhanced H2O2-induced apoptosis. H2O2induced activation of caspase-3 and phosphorylation of histone H2B at serine 14, a posttranslational modification required for nuclear condensation, which also were blocked by ERK1/2 inhibition. Furthermore, blockade of ERK1/2 resulted in an increase in Akt phosphorylation and blockade of Akt potentiated apoptosis and diminished the protective effect conferred by ERK inhibition in H2O2-treated cells. Although Z-DEVD-FMK, a caspase-3 inhibitor, was able to inhibit histone H2B phosphorylation and apoptosis, it did not affect ERK1/2 phosphorylation. We suggest that ERK elicits apoptosis in epithelial cells by activating caspase-3 and inhibiting Akt pathways and elicits nuclear condensation through caspase-3 and histone H2B phosophorylation during oxidant injury.

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Herbimycin A and Geldanamycin Inhibit Okadaic Acid-Induced Apoptosis and p38 Activation in NRK-52E Renal Epithelial Cells

Toxicology and Applied Pharmacology ◽

10.1006/taap.1999.8765 ◽

1999 ◽

Vol 161 (1) ◽

pp. 59-74 ◽

Cited By ~ 11

Author(s):

M.A. Davis ◽

D.E. Carbott

Keyword(s):

Epithelial Cells ◽

Okadaic Acid ◽

Renal Epithelial Cells ◽

Herbimycin A ◽

Induced Apoptosis

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Mcl-1 is downregulated in cisplatin-induced apoptosis, and proteasome inhibitors restore Mcl-1 and promote survival in renal tubular epithelial cells

AJP Renal Physiology ◽

10.1152/ajprenal.00505.2006 ◽

2007 ◽

Vol 292 (6) ◽

pp. F1710-F1717 ◽

Cited By ~ 28

Author(s):

Cheng Yang ◽

Varsha Kaushal ◽

Sudhir V. Shah ◽

Gur P. Kaushal

Keyword(s):

Epithelial Cells ◽

Cytochrome C ◽

Caspase 3 ◽

Proteasome Inhibitors ◽

Mrna Levels ◽

Dependent Manner ◽

Tubular Epithelial Cells ◽

Renal Tubular Epithelial Cells ◽

Renal Tubular ◽

Induced Apoptosis

Mcl-1 is an antiapoptotic member of the Bcl-2 family that plays an important role in cell survival. We demonstrate that proteasome-dependent regulation of Mcl-1 plays a critical role in renal tubular epithelial cell injury from cisplatin. Protein levels of Mcl-1 rapidly declined in a time-dependent manner following cisplatin treatment of LLC-PK1cells. However, mRNA levels of Mcl-1 were not altered following cisplatin treatment. Expression of other antiapoptotic members of the Bcl-2 family such as Bcl-2 and BclxL was not affected by cisplatin treatment. Cisplatin-induced loss of Mcl-1 occurs at the same time as the mitochondrial release of cytochrome c, activation of caspase-3, and initiation of apoptosis. Treatment of cells with cycloheximide, a protein synthesis inhibitor, revealed rapid turnover of Mcl-1. In addition, treatment with cycloheximide in the presence or absence of cisplatin demonstrated that cisplatin-induced loss of Mcl-1 results from posttranslational degradation rather than transcriptional inhibition. Overexpression of Mcl-1 protected cells from cisplatin-induced caspase-3 activation and apoptosis. Preincubating cells with the proteasome inhibitor MG-132 or lactacystin not only restored cisplatin-induced loss of Mcl-1 but also resulted in an accumulation of Mcl-1 that exceeded basal levels; however, Bcl-2 and BclxL levels did not change in response to MG-132 or lactacystin. The proteasome inhibitors effectively blocked cisplatin-induced mitochondrial release of cytochrome c, caspase-3 activation, and apoptosis. These studies suggest that proteasome regulation of Mcl-1 is crucial in the cisplatin-induced apoptosis via the mitochondrial apoptotic pathway and that Mcl-1 is an important therapeutic target in cisplatin injury to renal tubular epithelial cells.

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