GSK3B and acute kidney injury: To ascertain if impaired Nrf2 response is also present in human AKI to CKD transition and associated with GSK3β hyperactivity as well, we next examined kidney biopsy specimens from patients with progressive CKD that was developed after a documented antecedent episode of AKI due to diverse etiologies, including administration of iodinated radiocontrast media, contraction of the extracellular fluid volume and ingestion of aristolochic acid-containing herbs.