Which dietary and botanical substances inhibit 15‑hydroxy‑prostaglandin dehydrogenase?

Dietary and Botanical Substances that Inhibit 15-PGDH

Panaxynol, a polyacetylene compound isolated from oriental medicines (including ginseng), is the most well-documented botanical substance that inhibits 15-hydroxyprostaglandin dehydrogenase (15-PGDH), with an IC50 of approximately 25 μM through non-competitive inhibition. 1

Evidence-Based Inhibitors

Botanical Compounds

Panaxynol stands out as the primary botanical inhibitor with direct experimental evidence:

• Isolated from commonly used oriental medicines (particularly ginseng species)
• Demonstrates dose-dependent inhibition at concentrations of 25-200 μM
• Mechanism: Non-competitive inhibition with respect to both NAD+ and prostaglandin E2
• Does not affect prostaglandin synthesis enzymes (COX pathway remains intact)
• Has additional anti-inflammatory and anti-platelet effects 1

Phytophenolic compounds have also been identified as potent 15-PGDH inhibitors, though specific compounds are not detailed in the available evidence 2

Pharmaceutical Compounds with Dietary Relevance

While not strictly "dietary," several compounds with chemopreventive properties that may be found in supplements inhibit 15-PGDH 2:

Green tea catechins (particularly EGCG - epigallocatechin-3-gallate):

• While primarily discussed for AGE inhibition in the evidence, green tea supplements are noted to have antiplatelet effects 3
• EGCG is mentioned as an active ingredient in green tea with biological activity 4

Ciglitazone (a PPAR-gamma agonist):

• Most potent inhibitor identified with IC50 = 2.7 μM
• Non-competitive inhibition with respect to NAD+
• Uncompetitive with respect to PGE2
• Note: This is a pharmaceutical compound, not a dietary substance, but related compounds may exist in botanical sources 2

Clinical Context and Mechanism

Why 15-PGDH inhibition matters:

• 15-PGDH degrades prostaglandin E2 (PGE2), which is protective in multiple tissues
• Inhibiting 15-PGDH increases local PGE2 levels
• This promotes tissue regeneration in cartilage, skeletal muscle, and other organs 5, 6, 7
• May have therapeutic potential for osteoarthritis, ischemic stroke, and contrast-induced kidney injury

Important Caveats

Aspirin paradox: While aspirin inhibits COX enzymes (reducing PGE2 synthesis), the evidence discusses aspirin's effects being potentially enhanced by HPGD (another name for 15-PGDH) expression, which catabolizes PGE2. This suggests a complex interplay where 15-PGDH inhibition could theoretically work synergistically with or against aspirin's effects depending on the tissue context 8

Bleeding risk considerations:

• Green tea supplements containing EGCG can inhibit platelet aggregation 3
• Should be discontinued 1-2 weeks before surgery
• May interact with anticoagulants

Limited human data: Most evidence for dietary/botanical 15-PGDH inhibitors comes from in vitro studies. The clinical efficacy and optimal dosing in humans remain largely unexplored.

Practical Recommendations

For someone seeking dietary/botanical 15-PGDH inhibition:

• Panaxynol-containing products (ginseng preparations) have the strongest direct evidence
• Green tea (particularly high-EGCG preparations) may provide additional benefits through multiple mechanisms
• Avoid concurrent use with anticoagulants or NSAIDs without medical supervision
• Discontinue before surgical procedures

The evidence base for dietary and botanical 15-PGDH inhibitors remains limited compared to synthetic pharmaceutical inhibitors (like SW033291), which show more robust effects in experimental models 9, 5, 6, 7.