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

Executive Summary: WY-14643 (Pirinixic Acid) is a selective PPARα agonist with an IC50 of 10.11 µM for human PPARα, acting as a dual PPARα/γ agonist in the low micromolar range [APExBIO]. In vivo, 3 mg/kg/day oral administration improves insulin sensitivity and reduces triglycerides in high-fat-fed rats [Ref1]. WY-14643 downregulates VCAM-1 expression in endothelial cells, mitigating TNF-α–induced monocyte adhesion [Ref2]. In mouse models, 100 mg/kg/day intraperitoneal administration induces hepatomegaly and activates liver regeneration through the YAP-TEAD–PPARα pathway [Ref3]. The compound is insoluble in water, but soluble in DMSO (≥16.2 mg/mL) and ethanol (≥48.8 mg/mL, ultrasonic-assisted), and is available as SKU A4305 from APExBIO for research use only [APExBIO].

Biological Rationale

Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear receptor that regulates lipid metabolism, inflammation, and energy homeostasis [Ref1]. PPARα modulates the transcription of genes involved in fatty acid oxidation, lipoprotein assembly, and glucose metabolism. Dysregulation of PPARα is associated with metabolic disorders, non-alcoholic fatty liver disease (NAFLD), and chronic inflammation. Selective PPARα agonists such as WY-14643 are critical tools for dissecting these pathways in preclinical models [Ref3]. Recent findings emphasize the importance of dual PPARα/γ agonists for synergistically targeting metabolic and inflammatory endpoints [Ref2].

Mechanism of Action of WY-14643 (Pirinixic Acid)

WY-14643 (Pirinixic Acid) acts as a high-affinity, selective agonist of PPARα, binding to its ligand-binding domain and promoting heterodimerization with RXRα. This complex binds to peroxisome proliferator response elements (PPREs) in DNA, activating transcription of target genes involved in fatty acid β-oxidation and lipid transport [APExBIO]. The compound also exhibits dual PPARα/γ agonism when aliphatic α-substitution is introduced, enhancing effects on both lipid and glucose homeostasis [Ref1]. In endothelial cells, WY-14643 inhibits TNF-α–induced VCAM-1 expression and monocyte adhesion, indicating anti-inflammatory signaling [Ref2]. In hepatic tissue, activation of PPARα by WY-14643 induces hepatomegaly and liver regeneration via the YAP-TEAD pathway, as validated in murine models [Ref3].

Evidence & Benchmarks

• WY-14643 activates human PPARα with an IC50 of 10.11 µM under standard biochemical assay conditions (37°C, pH 7.4, 1% DMSO) (APExBIO).
• Aliphatic α-substitution leads to balanced dual agonism at PPARα and PPARγ in the low micromolar range, validated in cell-based luciferase reporter assays (Ref1).
• Pretreatment with 250 μM WY-14643 in endothelial cell culture (37°C, 5% CO2, 24 h) significantly reduces TNF-α–induced VCAM-1 expression and monocyte adhesion by >50% (Ref2).
• In high-fat-fed rats, oral WY-14643 at 3 mg/kg/day for 2 weeks decreases plasma glucose, triglycerides, leptin, and liver triglyceride content, with no increase in body weight (Ref1).
• Mouse models receiving intraperitoneal WY-14643 (100 mg/kg/day for 10 days) show increased hepatocyte proliferation (KI67+ cells) and liver mass, mediated by YAP-TEAD pathway activation (Ref3).
• WY-14643 is a solid, water-insoluble compound, soluble in DMSO (≥16.2 mg/mL) and ethanol (≥48.8 mg/mL, ultrasonication), recommended for storage at –20°C (APExBIO).

For a broader discussion of translational and workflow scenarios, see this recent analysis, which focuses on mechanistic insights at the interface of inflammation and metabolic regulation. This article extends previous coverage by clarifying dual PPARα/γ benchmarks and detailing YAP-TEAD–mediated hepatic effects. Additionally, see this review, which emphasizes WY-14643 in tumor microenvironment studies; the current article updates the metabolic and workflow context.

Applications, Limits & Misconceptions

WY-14643 is widely used in preclinical models to dissect the PPAR signaling pathway, metabolic disorder mechanisms, and TNF-α–mediated inflammation. It is suitable for in vitro studies (250 μM typical concentration for human endothelial cells) and in vivo rodent models (oral: 3 mg/kg/day; intraperitoneal: 100 mg/kg/day) [APExBIO]. Its dual PPARα/γ agonism allows examination of overlapping metabolic and inflammatory processes. Applications include:

• Modeling hepatic lipid metabolism, insulin sensitivity, and liver regeneration (YAP-TEAD pathway involvement).
• Evaluating anti-inflammatory mechanisms, such as VCAM-1 regulation and monocyte adhesion.
• Dissecting PPARα and PPARγ cross-talk in metabolic syndrome and cardiovascular disease models.

However, WY-14643 should not be used for diagnostic or therapeutic purposes in humans. Variability in response due to species, tissue context, and compound formulation should be considered. Some misconceptions persist regarding its selectivity and in vivo translation:

Common Pitfalls or Misconceptions

• WY-14643 is not a pan-PPAR agonist; its primary activity is at PPARα, with dual activity only upon specific α-substitution.
• It is not suitable for water-based formulations due to insolubility; DMSO or ethanol (with ultrasonication) is required for dissolution.
• In vivo efficacy and toxicity can vary between species; rodent doses may not extrapolate directly to higher mammals or humans.
• WY-14643 is not approved for clinical, diagnostic, or veterinary applications; it is strictly for laboratory research.
• Observed hepatomegaly with high-dose WY-14643 in mice is YAP-TEAD dependent and not solely a direct PPARα effect.

Workflow Integration & Parameters

For cell-based assays, dissolve WY-14643 in DMSO at ≥16.2 mg/mL, filter sterilize, and dilute to working concentrations (up to 250 μM for endothelial cells). For animal studies, oral dosing at 3 mg/kg/day or intraperitoneal administration at 100 mg/kg/day are supported benchmarks for metabolic and hepatic endpoints, respectively [Ref1]. Prepare fresh solutions or store aliquots at –20°C for short-term use. Avoid repeated freeze-thaw cycles. Monitor for batch-to-batch consistency when sourcing from commercial suppliers such as APExBIO. Adhere to institutional and ethical protocols for animal and cellular experimentation. For additional workflow optimization, refer to this practical guide; this article updates integration benchmarks with recent evidence for dual agonist activity and YAP-TEAD pathway validation.

Conclusion & Outlook

WY-14643 (Pirinixic Acid) remains a premier research tool for dissecting PPARα signaling, lipid and glucose metabolism, and TNF-α–mediated inflammation in cellular and animal models. Its robust dual PPARα/γ agonist profile, well-characterized pharmacology, and validated workflow parameters support broad utility in metabolic disorder and inflammation research. Ongoing studies on the YAP-TEAD pathway and translational endpoints will further refine its applications. For detailed specifications or to procure the A4305 kit, visit the APExBIO WY-14643 product page.