Perirenal Fat in Disease Progression: From Inflammatory Mediator to Therapeutic Target
Eiji Kashiwagi
Abstract
Perirenal fat (PRF), the adipose tissue that encases the kidneys, has long been considered a passive energy reservoir and mechanical buffer. However, emerging evidence has identified PRF as a biologically active visceral fat depot that secretes adipocytokines, inflammatory mediators, and other bioactive molecules, and thereby contributes to the pathogenesis and progression of several systemic diseases. PRF is associated with renal cell carcinoma, cardiovascular disease, chronic kidney disease, obesity, and metabolic syndrome. In renal cell carcinoma, PRF thickness correlates positively with tumor stage and negatively with prognosis. In cardiovascular and renal disorders, PRF accumulation is linked to elevated blood pressure and impaired renal function. Furthermore, PRF promotes a pro-inflammatory microenvironment that exacerbates chronic kidney disease and metabolic abnormalities. These findings underscore the clinical relevance of PRF, both as a diagnostic and prognostic marker and a potential target for therapeutic intervention. This review provides a comprehensive overview of the roles of PRF in disease development and progression and emphasizes its emerging significance in clinical practice.