Heme Oxygenase-1 Attenuates Cadmium-induced Mitochondrial-caspase 3- Dependent Apoptosis in Human Hepatoma Cell Line
Overview
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Background: Cadmium (Cd) is a well known environmental and industrial toxicant causing damaging effects in numerous organs. In this study, we examined the role of heme oxygenase-1 (HO-1) in modulating the Cd-induced apoptosis in human hepatoma (HepG2) cells after 24 h exposure.
Methods: HepG2 cells were exposed to 5 and 10 μM Cd as CdCl2 for 24 h while other sets of cells were pre-treated with either 10 μM Cobalt protoporphyrin (CoPPIX) or 10 μM Tin protoporphyrin (SnPPIX) for 24 h, or 50 μM Z-DEVD-FMK for 1 h before exposure to 5 and 10 μM CdCl2 for 24 h. Expressions of caspase 3, cytosolic cytochrome c, mitochondrial Bax and anti-apoptotic BCL-xl proteins were assessed by western blot. Intracellular reactive oxygen species (ROS) production was determined using the dihydrofluorescein diacetate (H2DFA) method. Cell viability was assessed by MTT assay, while a flow cytometry method was used to assess the level of apoptosis in the cell populations.
Results: Our results show that there were a significant increase in the expression of cytosolic cytochrome c, mitochondrial Bax protein, and caspase 3 at 5 and 10 μM compared to the control, but these increases were attenuated by the presence of CoPPIX. The presence of SnPPIX significantly enhanced Cd-induced caspase 3 activities. CoPPIX significantly decreased the level of ROS production by 24.6 and 22.2 % in 5 and 10 μM CdCl2, respectively, but SnPPIX caused a significant increase in ROS production in the presence of CdCl2. HepG2 cell viability was also significantly impaired by 13.89 and 32.53 % in the presence of 5 and 10 μM CdCl2, respectively, but the presence of CoPPIX and Z-DEVD-FMK significantly enhanced cell survival, while SnPPIX enhanced Cd-impaired cell viability. The presence of CoPPIX and Z-DEVD-FMK also significantly decreased the population of apoptotic and necrotic cells compared with Cd.
Conclusion: In summary, the present study showed that HO-1 attenuates the Cd-induced caspase 3 dependent pathway of apoptosis in HepG2 cells, probably by modulating Cd-induced oxidative stress.
Buranasudja V, Sanookpan K, Vimolmangkang S, Binalee A, Mika K, Krobthong S Heliyon. 2024; 10(18):e37424.
PMID: 39309955 PMC: 11416483. DOI: 10.1016/j.heliyon.2024.e37424.
Zhang R, Walker L, Wen X, Doherty C, Gorczyca L, Buckley B Reprod Toxicol. 2023; 121:108466.
PMID: 37660740 PMC: 10591833. DOI: 10.1016/j.reprotox.2023.108466.
Shahzadi A, Tariq N, Sonmez H, Waquar S, Zahid A, Javed M Front Chem. 2023; 11:1036478.
PMID: 36936530 PMC: 10016615. DOI: 10.3389/fchem.2023.1036478.
Oxidant- induced preconditioning: A pharmacologic approach for triggering renal 'self defense'.
Zager R Physiol Rep. 2022; 10(20):e15507.
PMID: 36305701 PMC: 9615572. DOI: 10.14814/phy2.15507.
Schneider F, Krieg S, Lindauer U, Stoffel M, Ryang Y Biology (Basel). 2022; 11(2).
PMID: 35205025 PMC: 8869506. DOI: 10.3390/biology11020158.