ID: h-be9bab57
Hypothesis
PGE2–EP2–cAMP–PKA Axis Displaces Pathological Microglial Memory Traces
Astrocyte-produced PGE2 (via COX2 induction) engages microglial EP2 receptors, elevating cAMP and activating PKA.
🧬 PTGER2 (EP2) → ADCY → cAMP → PRKA (PKA) → SIRT1🩺 neuroinflammation🎯 Composite 68%💱 $0.62▼18.7%proposed
EvidencePending (0%)📖 8 cit🗣 1 debates✓ 8 support✗ 2 oppose
✓ All Quality Gates Passed
🧪 Overview
Astrocyte-produced PGE2 (via COX2 induction) engages microglial EP2 receptors, elevating cAMP and activating PKA. PKA phosphorylates NF-κB p65(S276), altering transcriptional kinetics. Simultaneously, PKA activates SIRT1, which deacetylates H4K16 at trained enhancers, destabilizing the epigenetic memory complex (BET proteins + BRD4). Strong pharmacological tractability due to existing EP2 agonists.
🧬 Mechanism
🧬 Curated Mechanism Pathway
Curated pathway from expert analysis
flowchart TD
A["NAD+ Availability<br/>NAMPT-Dependent"]
B["SIRT1 Activation<br/>NAD+-Dependent Deacetylase"]
C["PGC1alpha Deacetylation<br/>Mitochondrial Gene Activation"]
D["Mitochondrial Biogenesis<br/>Oxidative Phosphorylation"]
E["FOXO Deacetylation<br/>Antioxidant Response"]
F["NF-kB p65 Deacetylation<br/>Inflammation Suppression"]
G["Tau Deacetylation<br/>Proteasomal Clearance"]
H["Neuroprotection<br/>Extended Lifespan"]
A --> B
B --> C
B --> E
B --> F
B --> G
C --> D
D --> H
E --> H
F --> H
G --> H
style A fill:#1a237e,stroke:#4fc3f7,color:#4fc3f7
style H fill:#1b5e20,stroke:#81c784,color:#81c784⚖️ Evidence
⚖️ Evidence Matrix8 supports2 contradicts
Supports
Restoring metabolism of myeloid cells reverses cognitive decline in ageing.
Supports
Cyclooxygenase-1 deletion in 5 × FAD mice protects against microglia-induced neuroinflammation and mitigates cognitive impairment.
Supports
Suppression of inflammation with conditional deletion of the prostaglandin E2 EP2 receptor in macrophages and brain microglia.
Supports
Novel Microglia Cell Line Expressing the Human EP2 Receptor.
Contradicts
PGE2 signaling has complex, often pro-inflammatory roles depending on receptor subtype (EP2 vs EP4)
Contradicts
Systemic COX2 inhibition associated with cardiovascular risks limits therapeutic window
📖 Linked Papers
No linked papers recorded for this hypothesis yet.
🏥 Translation
🧬 3D Protein Structure — PTGER2
No curated PDB or AlphaFold mapping for PTGER2 yet. Search RCSB →
🧠 GTEx v10 Brain ExpressionJSON
Median TPM across 13 brain regions for PTGER2 (EP2) → ADCY → cAMP → PRKA (PKA) → SIRT1 from GTEx v10.
💉 Clinical Trials
No clinical trials data linked to this hypothesis yet.
No curated ClinVar variants loaded for this hypothesis.
Run scripts/backfill_clinvar_variants.py to fetch P/LP/VUS variants.
No DepMap CRISPR Chronos data found for PTGER2 (EP2) → ADCY → cAMP → PRKA (PKA) → SIRT1.
Run python3 scripts/backfill_hypothesis_depmap.py to populate.
🏆 Tournament
🏆 Arenas / Elo
No arena matches recorded yet. Browse Arenas →
📊 Market Indicators
7d Trend
↘
Falling
7d Momentum
▼ 1.6%
Volatility
Medium
0.0371
Events (7d)
3
Price History
▼18.7%💾 Resource Usage
LLM Tokens
13,698
$0.0411
Total Cost
$0.0411
🔮 Predictions
🔎 Predictions vs Observations2 predictions · 0 with recorded observations
| Prediction | Predicted | Observed | Status | Conf |
|---|---|---|---|---|
| IF EP2 agonist treatment is administered to LPS-primed microglia, THEN SIRT1 deacetylase activity will increase by ≥30% and H4K16ac levels at trained enhancers (Il6, Tnf promoters) will decrease by ≥5 | SIRT1 activity assay shows ≥30% increase; ChIP-qPCR reveals ≥50% reduction in H4K16ac at Il6/Tnf trained enhancers; BRD4 ChIP-qPCR shows ≥40% reduced occupancy | — no observation — | pending | 0.60 |
| IF microglial EP2 receptors are activated with a selective agonist (butaprost, 10 μM) for 48 hours following LPS priming (10 ng/ml, 24h), THEN the inflammatory cytokine response (IL-6, TNF-α) to a sec | ≥40% reduction in IL-6 and TNF-α secretion upon restimulation in EP2-agonist-treated primed microglia relative to vehicle controls | — no observation — | pending | 0.65 |
🔮 Falsifiable Predictions (2)
pendingconf 65%
IF microglial EP2 receptors are activated with a selective agonist (butaprost, 10 μM) for 48 hours following LPS priming (10 ng/ml, 24h), THEN the inflammatory cytokine response (IL-6, TNF-α) to a secondary LPS challenge (100 ng/ml, 6h) will be reduced by ≥40% compared to vehicle-treated primed micr
Predicted outcome: ≥40% reduction in IL-6 and TNF-α secretion upon restimulation in EP2-agonist-treated primed microglia relative to vehicle controls
Falsification: No significant reduction (p>0.05) or increase in cytokine secretion after EP2 activation; trained immunity phenotype persists unchanged
pendingconf 60%
IF EP2 agonist treatment is administered to LPS-primed microglia, THEN SIRT1 deacetylase activity will increase by ≥30% and H4K16ac levels at trained enhancers (Il6, Tnf promoters) will decrease by ≥50% within 48 hours, with concurrent destabilization of BRD4 chromatin binding.
Predicted outcome: SIRT1 activity assay shows ≥30% increase; ChIP-qPCR reveals ≥50% reduction in H4K16ac at Il6/Tnf trained enhancers; BRD4 ChIP-qPCR shows ≥40% reduced
Falsification: SIRT1 activity remains unchanged, H4K16ac levels do not decrease, or BRD4 binding is unaffected by EP2 activation—indicating the epigenetic memory displacement mechanism is non-functional
▸Metadatasource: v1_phase_c_backfill · origin_type: gap_debate
| source | v1_phase_c_backfill |
| origin_type | gap_debate |
| _schema_version | 1 |
📊 Evidence Profile
Evidence Balance
+0%
Certainty
0%
Debates
0
Incoming
0
Outgoing
0
0 supporting
0 contradicting
0 neutral
Public annotations (0)Annotate on Hypothes.is →
No public annotations yet.