# Alpha-1 Antitrypsin Protects Against Cisplatin-Induced Acute Kidney Injury by Restoring Redox and Mitochondrial Homeostasis

## TL;DR

Alpha-1 antitrypsin (AAT) protects the kidneys from cisplatin damage by reducing inflammation, restoring redox balance, and improving mitochondrial function.

## Contribution

This study demonstrates that AAT ameliorates cisplatin-induced acute kidney injury by restoring redox and mitochondrial homeostasis.

## Key findings

- AAT reversed cisplatin-induced renal dysfunction and tubular injury.
- AAT restored redox balance and corrected NOX isoform imbalances.
- AAT improved mitochondrial metabolism and reduced inflammation and apoptosis.

## Abstract

Cisplatin is an effective chemotherapeutic agent, yet its clinical utility is limited by dose-dependent nephrotoxicity. Alpha-1 antitrypsin (AAT) has cytoprotective, anti-inflammatory, and antiapoptotic properties, but its therapeutic potential in cisplatin-induced acute kidney injury (AKI) remains unclear. A murine cisplatin–AKI model was used to evaluate whether AAT (80 mg/kg) ameliorates renal injury. Renal function, oxidative stress, NADPH oxidase (NOX) isoforms, mitochondrial metabolism, inflammatory mediators, apoptosis, and fibrosis-related markers were assessed using biochemical, histological, immunohistochemical, and Western blot analyses. Cisplatin markedly impaired renal function and induced tubular injury; meanwhile, AAT significantly reversed these changes. Cisplatin also induced severe oxidative stress and disrupted the balance of NOX isoforms; AAT restored redox homeostasis. Cisplatin upregulated CPT1A/PDK4 and suppressed CPT2, UCP3, PGC1α, and DRP1, inducing maladaptive mitochondrial changes, indicating impaired β-oxidation and defective mitochondrial dynamics; AAT reversed these alterations, restoring normal mitochondrial metabolism. IL-1β, IL-6R, OPN, and F4/80 expression, recovery of the Bax/Bcl-2 ratio, and MAPK activation were reduced, indicating decreased inflammation and apoptosis; profibrotic markers were also reduced. AAT confers multifaceted protection against cisplatin-induced AKI by restoring redox balance, mitochondrial homeostasis, and inflammatory and apoptotic signaling. These findings support AAT as a promising therapeutic agent for preventing cisplatin nephrotoxicity.