Oxidative Stress and X-ray Exposure Levels-Dependent Survival and Metabolic Changes in Murine HSPCs.
Melis KarabulutogluRosemary FinnonLourdes Cruz-GarciaMark A HillChristophe BadiePublished in: Antioxidants (Basel, Switzerland) (2021)
Haematopoietic bone marrow cells are amongst the most sensitive to ionizing radiation (IR), initially resulting in cell death or genotoxicity that may later lead to leukaemia development, most frequently Acute Myeloid Leukaemia (AML). The target cells for radiation-induced Acute Myeloid Leukaemia (rAML) are believed to lie in the haematopoietic stem and progenitor cell (HSPC) compartment. Using the inbred strain CBA/Ca as a murine model of rAML, progress has been made in understanding the underlying mechanisms, characterisation of target cell population and responses to IR. Complex regulatory systems maintain haematopoietic homeostasis which may act to modulate the risk of rAML. However, little is currently known about the role of metabolic factors and diet in these regulatory systems and modification of the risk of AML development. This study characterises cellular proliferative and clonogenic potential as well as metabolic changes within murine HSPCs under oxidative stress and X-ray exposure. Ambient oxygen (normoxia; 20.8% O 2 ) levels were found to increase irradiated HSPC-stress, stimulating proliferative activity compared to low oxygen (3% O 2 ) levels. IR exposure has a negative influence on the proliferative capability of HSPCs in a dose-dependent manner (0-2 Gy) and this is more pronounced under a normoxic state. One Gy x-irradiated HSPCs cultured under normoxic conditions displayed a significant increase in oxygen consumption compared to those cultured under low O 2 conditions and to unirradiated HSPCs. Furthermore, mitochondrial analyses revealed a significant increase in mitochondrial DNA (mtDNA) content, mitochondrial mass and membrane potential in a dose-dependent manner under normoxic conditions. Our results demonstrate that both IR and normoxia act as stressors for HSPCs, leading to significant metabolic deregulation and mitochondrial dysfunctionality which may affect long term risks such as leukaemia.
Keyphrases
- oxidative stress
- induced apoptosis
- mitochondrial dna
- bone marrow
- cell cycle arrest
- acute myeloid leukemia
- cell death
- copy number
- ischemia reperfusion injury
- diabetic rats
- endoplasmic reticulum stress
- endothelial cells
- single cell
- high resolution
- transcription factor
- physical activity
- mesenchymal stem cells
- human health
- magnetic resonance imaging
- signaling pathway
- gene expression
- air pollution
- liver failure
- allogeneic hematopoietic stem cell transplantation
- intensive care unit
- immune response
- risk assessment
- computed tomography
- pi k akt
- aortic dissection
- cell therapy
- radiation induced
- climate change
- magnetic resonance
- protein kinase