Narrative review explores aryl hydrocarbon receptor's dual role in liver injury and protection

This narrative review synthesizes current knowledge on the aryl hydrocarbon receptor (AhR) in liver injury and disease. The authors describe AhR's dual role: on one hand, its activation contributes to liver damage via mitochondrial dysfunction, oxidative stress, DNA damage, aberrant metabolic activation, hepatocyte apoptosis, steatosis, and inflammatory responses. On the other hand, AhR activation can also produce hepatoprotective effects, including inhibition of hepatic stellate cell activation and fibrogenesis, induction of anti-inflammatory phenotypes in immune cells, and regulation of bile acid and lipid metabolic homeostasis.

As a narrative review, this article does not provide pooled effect sizes, p-values, or confidence intervals. The evidence is drawn from a range of preclinical and mechanistic studies, and the authors do not report specific study populations, sample sizes, or comparators. The review does not include a systematic search methodology or formal quality assessment of included studies.

The authors acknowledge that the field is still evolving, and many questions remain about the context-dependent effects of AhR signaling. They do not report specific limitations of the review itself, such as publication bias or search strategy constraints.

For clinicians, this review offers a theoretical foundation for understanding AhR as a potential therapeutic target in liver disease. However, direct clinical applicability is limited until further research clarifies the conditions under which AhR activation is harmful versus protective, and until AhR-targeted interventions are tested in clinical trials.