Preclinical studies have demonstrated that serum Klotho protein levels are significantly reduced in rat models of AKI, while exogenous Klotho supplementation exhibits renoprotective effects21.This study revealed that traumatic brain injury induces elevated serum Klotho protein levels, yet the defenite mechanisms are still ambiguous due to studies on serum Klotho andTBI are scarce.Interestingly, patients with TBI complicated by AKI exhibited significantly lower Klotho level compared to those without AKI. The gene discussed is KL; the disease is brain injury.