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Relationship: 1748
Title
Decreased, PPARalpha transactivation of gene expression leads to Fatty Acid Beta Oxidation, Decreased
Upstream event
Downstream event
AOPs Referencing Relationship
| AOP Name | Adjacency | Weight of Evidence | Quantitative Understanding | Point of Contact | Author Status | OECD Status |
|---|---|---|---|---|---|---|
| Antagonist binding to PPARα leading to body-weight loss | adjacent | High | High | Agnes Aggy (send email) | Open for citation & comment | WPHA/WNT Endorsed |
Taxonomic Applicability
Sex Applicability
| Sex | Evidence |
|---|---|
| Male | High |
| Female | High |
Life Stage Applicability
| Term | Evidence |
|---|---|
| Adult, reproductively mature | High |
PPARα acts as a positive transcriptional regulator for many of the genes involved in peroxisomal and mitochondrial fatty acid beta oxidation as well as genes involved in the pre- and post-processing of fatty acids in peroxisomal pathways (Desvergne and Wahili 1999, Kersten 2014). Inhibition of PPARα transactivation (KE1) results in decreased transcriptional expression for genes that catalyze the peroxisomal and mitochondrial fatty acid beta oxidation pathways (Desvergne and Wahili 1999, Kersten 2014, Dreyer et al. 1992, Lazarow 1978) by inhibiting expression of the enzymes involved in fatty acid metabolism. The processes involved in both peroxisomal and mitochondrial fatty acid beta-oxidation, are well described in the literature including good coverage of the gene products that catalyze the metabolic reactions (Kersten 2014) with reasonable characterization of metabolic flux (Mannaerts and Van Veldhoven 1993, Desvergne and Wahli 1999), thus the WOE scores for KER were in the medium to medium-high range.
| 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
The KER relationship between the KE, “decreased PPARα transactivation of gene expression” and the KE, “decreased fatty acid beta oxidation” is well supported by the literature (see references above). Few uncertainties remain, and few inconsistencies have been reported.
Unknown.
A large body of research demonstrated that PPARα nuclear signaling directly controls transcriptional expression for genes catalyzing peroxisomal beta-oxidation of very long chain fatty acids (>20C), mitochondrial beta-oxidation of short, medium and long chain fatty acids (<20C), and ketogenesis (as reviewed in Kersten 2014, Evans et al 2004, Desvergne and Wahli 1999, Sanderson et al 2010). The majority of the research described in these reviews was established using gene knock outs, so there is not much dose-response information available describing the KE, “decreased PPARα transactivation of gene expression” -> the KE, “decreased fatty acid beta oxidation”.
Response-response Relationship
Unknown.
Time-scale
Rapid Molecular Interactions.
Known Feedforward/Feedback loops influencing this KER
Unknown.
The relationships described herein have been primarily established in human and rodent models although the processes are fundamental in biology and likely broadly conserved.