Growth differentiation factor 11 attenuates sepsis-associated acute kidney injury by reducing inflammation and coagulation via PGC-1α/Nrf2 activation.

BACKGROUND: Patients with sepsis commonly endure severe renal dysfunction and damage, hastening to end-stage renal failure with high mortality, and effective treatment options are currently lacking. Growth differentiation factor 11 (GDF11), belonging to the transforming growth factor beta (TGF-β) superfamily, has shown therapeutic potential for numerous acute and chronic inflammatory conditions. Nevertheless, its function in sepsis-associated acute kidney injury (SAKI) remains unclear. PURPOSE: This study sought to explore GDF11's role in SAKI and determine the signaling pathways it modulates. METHODS: Alterations in GDF11 expression in the kidneys of mice with SAKI were analyzed. The influence of GDF11 knockdown and recombinant GDF11 (rGDF11) supplementation on cecal ligation and puncture (CLP)-induced SAKI in mice was determined. RNA sequencing, Western blot, real-time quantitative polymerase chain reaction (RT-qPCR), and kit assays were performed to explore the underlying mechanisms. RESULTS: Tubular epithelial cells and macrophages in the kidneys of CLP-induced SAKI mice exhibited high levels of GDF11 expression. Moreover, gene silencing of GDF11 using adeno-associated virus (AAV) aggravated renal dysfunction, increased tubular damage, and augmented renal apoptosis in CLP-induced SAKI mice. In contrast, replenishment of rGDF11 significantly mitigated these adverse effects. Further studies indicated that GDF11 stimulated the nuclear factor erythroid 2-related factor 2 (Nrf2)-regulated antioxidative pathways, primarily by inducing the expression of Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), which subsequently decreased excessive inflammation and coagulation. Additionally, these beneficial effects of GDF11 were largely diminished by AAV-mediated PGC-1α knockdown and depletion of Nrf2 in CLP-induced SAKI mice. CONCLUSIONS: In summary, these findings indicate that GDF11 is a potential therapeutic approach for SAKI and highlight the crucial role of PGC-1α/Nrf2 signaling in GDF11-mediated renal protection during SAKI.