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Relationship: 1828
Title
Inhibition, Nuclear factor kappa B (NF-kB) leads to Activation, Caspase 8 pathway
Upstream event
Downstream event
AOPs Referencing Relationship
| AOP Name | Adjacency | Weight of Evidence | Quantitative Understanding | Point of Contact | Author Status | OECD Status |
|---|---|---|---|---|---|---|
| IKK complex inhibition leading to liver injury | adjacent | Moderate | Moderate | Brendan Ferreri-Hanberry (send email) | Under development: Not open for comment. Do not cite |
Taxonomic Applicability
Sex Applicability
Life Stage Applicability
The downstream targets of NFkB are genes involved in cell survival and proliferation. When NFkB is inhibited, less of these cell survival genes will be transcribed, making the cell more susceptible for cell death pathways, like the caspase 8 pathway. (Frederiksson, 2012).In other words, lack of NFkB inhibition will lead to no inhibition of the capase pathway.
| 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
Caspase 8 activation leads to cell death but this is blocked in healthy cells by NFkB (Murphy 2012).
The balance between NfkB activation and cell death is complicated and includes crosstalk between several pathways. For example, not only target genes of NFkB signaling can induce survival, but also RIPK1 signaling with pro caspase8 block necrosis. (Brenner et al. 2015)
(Dondelinger et al. 2015) IKK subunits alpha and beta phosphorylate RIPK1, thereby inducing apoptosis via FADD/caspase-8: IKK inactivation induces cell death via RIPK1. NFkB is indeed inhibited and induces cell death, however, in parallel, RIPK1 dependent cell death is quicker. This pathway is also activated by IKK complex inactivation.