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Relationship: 2009
Title
Increased, Reactive oxygen species leads to Oxidative Stress
Upstream event
Downstream event
AOPs Referencing Relationship
| AOP Name | Adjacency | Weight of Evidence | Quantitative Understanding | Point of Contact | Author Status | OECD Status |
|---|---|---|---|---|---|---|
| Reactive Oxygen Species (ROS) formation leads to cancer via inflammation pathway | adjacent | High | Low | Evgeniia Kazymova (send email) | Under development: Not open for comment. Do not cite |
Taxonomic Applicability
Sex Applicability
| Sex | Evidence |
|---|---|
| Unspecific | High |
Life Stage Applicability
| Term | Evidence |
|---|---|
| All life stages | High |
Oxidative stress occurs due to the accumulation of reactive oxygen species (ROS). ROS can damage DNA, lipids, and proteins (Shields et al. 2021). Superoxide dismutase is an enzyme in a common cellular defense pathway, in which superoxide dismutase converts superoxide radicals to hydrogen peroxide. When cellular defense mechanisms are unable to mitigate ROS formation from mitochondrial respiration and stressors (biological, chemical, radiation), increased ROS levels cause oxidative stress.
This KER was identified as part of an Environmental Protection Agency effort to represent putative AOPs from peer-reviewed literature which were heretofore unrepresented in the AOP-Wiki. The KER is referenced in publications which were cited in the originating work for the putative AOP from Jeong and Choi (2020).
| ID | Experimental Design | Species | Upstream Observation | Downstream Observation | Citation (first author, year) | Notes |
|---|
| Title | First Author | Biological Plausibility |
Dose Concordance |
Temporal Concordance |
Incidence Concordance |
|---|
Biological Plausibility
Dose Concordance Evidence
Temporal Concordance Evidence
Incidence Concordance Evidence
Uncertainties and Inconsistencies
Free radicals or Reactive oxygen species (ROS) are directly measured. Oxidative stress can be detected through changes in gene expression (ex. superoxide dismutase, catalase, glutathione S-transferase), protein content (ex. glutathione), and enzyme activity (ex. superoxide dismutase, catalase, glutathione peroxidase).
Response-response Relationship
Time-scale
Known Feedforward/Feedback loops influencing this KER
Life Stage: The life stage applicable to this key event relationship is all life stages. Older individuals are more likely to manifest this adverse outcome pathway (adults > juveniles > embryos) due to accumulation of reactive oxygen species.
Sex: This key event relationship applies to both males and females.
Taxonomic: This key event relationship appears to be present broadly, with representative studies including mammals (humans, lab mice, lab rats), teleost fish, and invertebrates (cladocerans, mussels).