Limits...
Fenretinide induces mitochondrial ROS and inhibits the mitochondrial respiratory chain in neuroblastoma.

Cuperus R, Leen R, Tytgat GA, Caron HN, van Kuilenburg AB - Cell. Mol. Life Sci. (2009)

Bottom Line: ROS induction by fenretinide was of mitochondrial origin, demonstrated by detection of superoxide with MitoSOX, the scavenging effect of the mitochondrial antioxidant MitoQ and reduced ROS production in cells without a functional mitochondrial respiratory chain (Rho zero cells).In digitonin-permeabilized cells, a fenretinide concentration-dependent decrease in ATP synthesis and substrate oxidation was observed, reflecting inhibition of the mitochondrial respiratory chain.Co-incubation of fenretinide with inhibitors of different complexes of the respiratory chain suggested that fenretinide-induced ROS production occurred via complex II.

View Article: PubMed Central - PubMed

Affiliation: Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital, Academic Medical Centre, University of Amsterdam, P.O. Box 22700, 1100 DE, Amsterdam, The Netherlands.

ABSTRACT
Fenretinide induces apoptosis in neuroblastoma by induction of reactive oxygen species (ROS). In this study, we investigated the role of mitochondria in fenretinide-induced cytotoxicity and ROS production in six neuroblastoma cell lines. ROS induction by fenretinide was of mitochondrial origin, demonstrated by detection of superoxide with MitoSOX, the scavenging effect of the mitochondrial antioxidant MitoQ and reduced ROS production in cells without a functional mitochondrial respiratory chain (Rho zero cells). In digitonin-permeabilized cells, a fenretinide concentration-dependent decrease in ATP synthesis and substrate oxidation was observed, reflecting inhibition of the mitochondrial respiratory chain. However, inhibition of the mitochondrial respiratory chain was not required for ROS production. Co-incubation of fenretinide with inhibitors of different complexes of the respiratory chain suggested that fenretinide-induced ROS production occurred via complex II. The cytotoxicity of fenretinide was exerted through the generation of mitochondrial ROS and, at higher concentrations, also through inhibition of the mitochondrial respiratory chain.

Show MeSH

Related in: MedlinePlus

Effect of Trolox on loss of viability in 4HPR-treated cells. SJNB10 cells were incubated with 0–40 μM 4HPR with (grey bars) or without (black bars) 500 μM Trolox for 24 h. Viability was measured using the MTS method and was depicted as percentage of control. Each figure represents the mean ± SD of four experiments
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2824117&req=5

Fig7: Effect of Trolox on loss of viability in 4HPR-treated cells. SJNB10 cells were incubated with 0–40 μM 4HPR with (grey bars) or without (black bars) 500 μM Trolox for 24 h. Viability was measured using the MTS method and was depicted as percentage of control. Each figure represents the mean ± SD of four experiments

Mentions: Co-incubation with 4HPR and CCCP did not result in a decreased ROS production (data not shown). Thus, uncoupling the mitochondrial membrane did not prevent ROS production, which indicates that 4HPR-induced ROS production is not the result of inhibition of complex V of the mitochondrial respiratory chain. Trolox is an antioxidant that scavenged the 4HPR-induced ROS in neuroblastoma [6]. The decrease of the mitochondrial membrane potential induced by 4HPR could not be prevented by Trolox or MitoQ (data not shown) [6]. The activity of the mitochondrial respiratory chain in cells incubated with the combination of 4HPR and Trolox was investigated, and Trolox did not prevent the decrease of aspartate-ATP and malate-ATP (data not shown). In contrast, in cells incubated with low concentrations 4HPR (0–10 μM), the viability loss is attenuated by Trolox. However, when cells were incubated with higher 4HPR concentrations (20–40 μM), the loss of viability could not be fully prevented by Trolox (Fig. 7). These data suggest that the cytotoxicity of 4HPR is exerted through the generation of ROS at low concentrations of 4HPR, whereas inhibition of the mitochondrial respiratory chain might play a role at high concentrations of 4HPR.Fig. 7


Fenretinide induces mitochondrial ROS and inhibits the mitochondrial respiratory chain in neuroblastoma.

Cuperus R, Leen R, Tytgat GA, Caron HN, van Kuilenburg AB - Cell. Mol. Life Sci. (2009)

Effect of Trolox on loss of viability in 4HPR-treated cells. SJNB10 cells were incubated with 0–40 μM 4HPR with (grey bars) or without (black bars) 500 μM Trolox for 24 h. Viability was measured using the MTS method and was depicted as percentage of control. Each figure represents the mean ± SD of four experiments
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2824117&req=5

Fig7: Effect of Trolox on loss of viability in 4HPR-treated cells. SJNB10 cells were incubated with 0–40 μM 4HPR with (grey bars) or without (black bars) 500 μM Trolox for 24 h. Viability was measured using the MTS method and was depicted as percentage of control. Each figure represents the mean ± SD of four experiments
Mentions: Co-incubation with 4HPR and CCCP did not result in a decreased ROS production (data not shown). Thus, uncoupling the mitochondrial membrane did not prevent ROS production, which indicates that 4HPR-induced ROS production is not the result of inhibition of complex V of the mitochondrial respiratory chain. Trolox is an antioxidant that scavenged the 4HPR-induced ROS in neuroblastoma [6]. The decrease of the mitochondrial membrane potential induced by 4HPR could not be prevented by Trolox or MitoQ (data not shown) [6]. The activity of the mitochondrial respiratory chain in cells incubated with the combination of 4HPR and Trolox was investigated, and Trolox did not prevent the decrease of aspartate-ATP and malate-ATP (data not shown). In contrast, in cells incubated with low concentrations 4HPR (0–10 μM), the viability loss is attenuated by Trolox. However, when cells were incubated with higher 4HPR concentrations (20–40 μM), the loss of viability could not be fully prevented by Trolox (Fig. 7). These data suggest that the cytotoxicity of 4HPR is exerted through the generation of ROS at low concentrations of 4HPR, whereas inhibition of the mitochondrial respiratory chain might play a role at high concentrations of 4HPR.Fig. 7

Bottom Line: ROS induction by fenretinide was of mitochondrial origin, demonstrated by detection of superoxide with MitoSOX, the scavenging effect of the mitochondrial antioxidant MitoQ and reduced ROS production in cells without a functional mitochondrial respiratory chain (Rho zero cells).In digitonin-permeabilized cells, a fenretinide concentration-dependent decrease in ATP synthesis and substrate oxidation was observed, reflecting inhibition of the mitochondrial respiratory chain.Co-incubation of fenretinide with inhibitors of different complexes of the respiratory chain suggested that fenretinide-induced ROS production occurred via complex II.

View Article: PubMed Central - PubMed

Affiliation: Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital, Academic Medical Centre, University of Amsterdam, P.O. Box 22700, 1100 DE, Amsterdam, The Netherlands.

ABSTRACT
Fenretinide induces apoptosis in neuroblastoma by induction of reactive oxygen species (ROS). In this study, we investigated the role of mitochondria in fenretinide-induced cytotoxicity and ROS production in six neuroblastoma cell lines. ROS induction by fenretinide was of mitochondrial origin, demonstrated by detection of superoxide with MitoSOX, the scavenging effect of the mitochondrial antioxidant MitoQ and reduced ROS production in cells without a functional mitochondrial respiratory chain (Rho zero cells). In digitonin-permeabilized cells, a fenretinide concentration-dependent decrease in ATP synthesis and substrate oxidation was observed, reflecting inhibition of the mitochondrial respiratory chain. However, inhibition of the mitochondrial respiratory chain was not required for ROS production. Co-incubation of fenretinide with inhibitors of different complexes of the respiratory chain suggested that fenretinide-induced ROS production occurred via complex II. The cytotoxicity of fenretinide was exerted through the generation of mitochondrial ROS and, at higher concentrations, also through inhibition of the mitochondrial respiratory chain.

Show MeSH
Related in: MedlinePlus