A short treatment with resveratrol after a renal ischaemia–reperfusion injury prevents maladaptive repair and long‐term chronic kidney disease in rats

Acute kidney injury (AKI) often triggers physiological processes aimed at restoring renal function and architecture. However, this response can become maladaptive, leading to nephron loss and fibrosis. Although the therapeutic effects of resveratrol (RSV) are well established, its impact after AKI and for subsequent chronic kidney disease (CKD) remains unclear. This study assessed whether transient administration of RSV following ischaemia–reperfusion injury (IRI) could prevent the progression to CKD. Forty‐one male Wistar rats were assigned randomly to sham surgery, bilateral renal ischaemia for 30 min (IR) or IR+RSV. The RSV treatment commenced 24 h after IRI and continued for 10 days. The rats were studied for either 10 days or 5 months, after which kidney function and structure were evaluated. Mitochondrial homeostasis, oxidant defence and renal inflammation state were also evaluated. Despite having the same severity of AKI, rats receiving RSV for 10 days after IRI exhibited significant improvement in kidney histological injury and reduced inflammation, although renal haemodynamic recovery was less pronounced. Resveratrol effectively prevented the elevation of tubular injury‐related molecules and profibrotic signalling with reduced myofibroblast proliferation. Furthermore, RSV substantially improved the antioxidant response and mitochondrial homeostasis. After 5 months, RSV prevented the transition to CKD, as evidenced by the prevention of progressive proteinuria, renal dysfunction and tubulointerstitial fibrosis. This study demonstrates that a brief treatment with RSV following IRI is enough to prevent maladaptive repair and the development of CKD. Our findings highlight the importance of the early days of reperfusion, indicating that maladaptive responses can be reduced effectively following severe AKI. Key points Physiological processes activated after acute kidney injury (AKI) can lead to maladaptive responses, causing nephron loss and fibrosis. Prophylactic renoprotection with resveratrol (RSV) has been described in experimental AKI, but its impact after AKI and for subsequent chronic kidney disease (CKD) remains unclear. In this study, we found that histological tubular injury persists 10 days after ischaemia–reperfusion injury and contributes to a failed repair phenotype in proximal tubular cells. Short‐term RSV intervention influenced the post‐ischaemic repair response and accelerated tubular recovery by reducing oxidative stress and mitochondr