Blockade of TNF after ischemia reperfusion injury ameliorates renal prognosis

Recently, acute kidney injury (AKI) is thought to develop a predisposition toward chronic kidney disease. But the detailed mechanism of the disease progression after AKI is unknown. We made two ischemia-reperfusion injury (IRI) mice models, repaired kidney model and atrophic kidney model, and studied the mechanism that kidney after IRI became atrophy. We found that the atrophy kidney model had two peaks of apoptosis 3 and 14 days after IRI, whereas the repaired kidney model had only one apoptosis peak 3 days after IRI. We showed that the second apoptosis is responsible for the kidney atrophy. Moreover, apoptotic ligands, TNF and FasL were upregulated at the same time of two apoptosis peaks on the atrophic kidney, and blockade of them before IRI prevented kidney from falling into atrophy. Surprisingly, inhibition of the second apoptosis by anti-TNF antibody protected from renal atrophy. We propose that apoptosis might play a major role in AKI progression and blockade of TNF after IRI will be a new therapeutic approach for AKI.

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