WY-14643 (Pirinixic Acid): Selective PPARα Agonist for Metabolic and Inflammation Research

Executive Summary: WY-14643 (Pirinixic Acid) is a highly potent and selective agonist of peroxisome proliferator-activated receptor alpha (PPARα), with an IC₅₀ of 10.11 μM for human PPARα under standard assay conditions (APExBIO). The compound displays balanced dual PPARα/γ agonism upon α-substitution, enhancing its research utility in models of metabolic syndrome and inflammation (Methylpseudo-UTP). WY-14643 is proven to improve insulin sensitivity and reduce hepatic fat and inflammation markers in rodent models, without increasing body weight (AY-9944). In vivo, it induces hepatomegaly and liver regeneration via the YAP-TEAD pathway, contingent on intact PPARα signaling (see Evidence). The product is supplied by APExBIO (SKU: A4305), optimized for research use only.

Biological Rationale

Metabolic disorders such as non-alcoholic fatty liver disease (NAFLD), dyslipidemia, and type 2 diabetes are characterized by disruptions in lipid metabolism, insulin signaling, and chronic inflammation. PPARα is a nuclear receptor central to the regulation of lipid metabolism and fatty acid oxidation in the liver (Y27632.com). Selective activation of PPARα has been shown to lower plasma triglycerides, reduce hepatic steatosis, and modulate inflammatory gene expression.

WY-14643 (Pirinixic Acid) is a synthetic ligand developed as a potent tool to activate PPARα in experimental models. Its use has clarified the roles of PPAR signaling in both metabolic and immunometabolic contexts, including the regulation of TNF-α mediated inflammation and insulin sensitivity (Biotin-Tyramide). High-fat diet rodent studies demonstrate that WY-14643 reduces plasma glucose, triglycerides, and leptin, while also enhancing whole-body insulin sensitivity without promoting weight gain (Sulfonhsssbiotin).

Mechanism of Action of WY-14643 (Pirinixic Acid)

WY-14643 binds and activates PPARα, a ligand-activated transcription factor. Upon ligand binding, PPARα heterodimerizes with the retinoid X receptor (RXR) and translocates to the nucleus. There, it binds peroxisome proliferator response elements (PPREs) in the promoter regions of target genes, upregulating genes involved in fatty acid oxidation (e.g., ACOX1, CPT1A) and downregulating those involved in inflammation (e.g., VCAM-1, TNF-α) (APExBIO).

Aliphatic α-substitution of WY-14643 enhances agonistic activity for both PPARα and PPARγ, creating balanced dual agonists in the low micromolar range. This dual activity is relevant for dissecting the interplay between PPARα-driven lipid metabolism and PPARγ-driven glucose homeostasis. In mouse models, WY-14643 also activates the YAP-TEAD pathway, facilitating hepatocyte proliferation and liver regeneration following partial hepatectomy or injury (see Evidence).

Evidence & Benchmarks

• WY-14643 exhibits an IC₅₀ of 10.11 μM for human PPARα in cell-based reporter assays (APExBIO).
• In vitro, 250 μM WY-14643 pre-treatment reduces TNF-α-induced VCAM-1 expression and monocyte adhesion in endothelial cells, supporting anti-inflammatory action (Biotin-Tyramide).
• Oral administration (3 mg/kg/day, 2 weeks) in high-fat diet rats lowers plasma glucose, triglycerides, leptin, muscle triglycerides, and long-chain acyl-CoAs, and increases insulin sensitivity without increasing body weight (AY-9944).
• Intraperitoneal injection of 100 mg/kg/day WY-14643 for 10 days induces hepatomegaly and liver regeneration in C57BL/6 mice, dependent on functional PPARα and YAP-TEAD signaling (YAP-TEAD manuscript).
• WY-14643 is a solid compound, insoluble in water, but soluble in DMSO (≥16.2 mg/mL) and ethanol (≥48.8 mg/mL, ultrasonic assistance), and should be stored at -20°C for stability (APExBIO).

Applications, Limits & Misconceptions

WY-14643 is widely applied in studies of:

• Lipid metabolism regulation: Dissects fatty acid oxidation and lipid transport genes.
• Metabolic disorder research: Models for NAFLD, obesity, and diabetes.
• Anti-inflammatory research: Inhibition of TNF-α mediated endothelial activation.
• Liver regeneration models: Assesses hepatocyte proliferation via YAP-TEAD pathway.

This article extends prior coverage (methylpseudo-utp.com) by detailing YAP-TEAD pathway involvement, and clarifies dual PPARα/γ activity under α-substitution. It updates the metabolic endpoints benchmarked in recent rodent studies beyond the scope of AY-9944.com.

Common Pitfalls or Misconceptions

• WY-14643 is not selective for PPARγ; its dual activity emerges only after α-substitution.
• It is not suitable for clinical or diagnostic use; for research use only (APExBIO).
• Insoluble in water; improper solubilization leads to experimental failures.
• Effects on hepatomegaly and regeneration are PPARα- and YAP-dependent; knockout models do not respond.
• Dosage and administration routes must match those validated in literature for comparability.

Workflow Integration & Parameters

• Cellular studies: Pre-treat cells with 250 μM WY-14643 for 1–24 hours in DMSO or ethanol vehicle (Biotin-Tyramide).
• Animal studies: Oral administration at 3 mg/kg/day (rats) or intraperitoneal injection at 100 mg/kg/day (mice), duration 5–14 days (YAP-TEAD manuscript).
• Preparation: Dissolve in DMSO (≥16.2 mg/mL) or ethanol (≥48.8 mg/mL, ultrasound) immediately before use; store solid at -20°C (APExBIO).
• Controls: Use vehicle controls and, in knockout models, confirm target dependence.
• Consult the A4305 kit specifications for full handling and storage recommendations.

Conclusion & Outlook

WY-14643 (Pirinixic Acid) remains a reference compound for selective PPARα activation in metabolic and inflammation research. Its robust, reproducible effect profile and dual PPARα/γ potential following α-substitution provide mechanistic insight into lipid metabolism, insulin signaling, and the PPAR signaling pathway. The compound's proven role in driving hepatocyte proliferation via YAP-TEAD supports its utility in regenerative liver research. For translational workflows, strict adherence to validated protocols and recognition of its research-only status (per APExBIO) are essential. Further optimization and cross-validation in diverse disease models will clarify its broader impact and translational potential.