title: Local anesthetics induce human renal cell apoptosis.
abstract: Renal cell apoptosis contributes significantly to the pathogenesis of acute renal failure. Local anesthetics induce apoptosis in neuronal and lymphocytic cell lines. We examined the effects of chronic (48 h) local anesthetic treatment (lidocaine, bupivacaine and tetracaine) on human proximal tubular (HK-2) cells. Apoptosis induction was assessed by detecting poly(ADP)-ribose polymerase fragmentation, caspase activation, terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining, DNA laddering and by cellular morphology. Cell death was quantified by measuring neutral red dye uptake and lactate dehydrogenase released into the cell culture medium. All 3 local anesthetics caused concentration-dependent cell death, induced HK-2 cell apoptosis and potentiated TNF-alpha induced apoptosis. Local anesthetics induced HK-2 cell apoptosis by activation of caspases 3, 6, 7, 8 and 9. ZVAD-fmk, a pan-caspase inhibitor, blocked the local anesthetic induced HK-2 cell apoptosis. Local anesthetics also inhibited the activities of anti-apoptotic kinases protein kinase B (Akt) and extracellular signal regulated mitrogen-activated protein kinase. Local anesthetic's pro-apoptotic effects are independent of sodium channel inhibition as tetrodotoxin, a selective voltage-gated sodium channel blocker, failed to mimic local anesthetic-mediated induction or potentiation of HK-2 cell apoptosis. We conclude that local anesthetics induce human renal cell apoptotic signaling by caspase activation and via inhibition of pro-survival signaling pathways.
authors.affiliation: Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, NY 10032-3784, USA. tl128@columbia.edu
authors.forename: H Thomas
authors.initials: HT
authors.lastname: Lee
authors.forename: Hua
authors.initials: H
authors.lastname: Xu
authors.forename: Cory D
authors.initials: CD
authors.lastname: Siegel
authors.forename: Igor E
authors.initials: IE
authors.lastname: Krichevsky
mesh_terms: D000704:Analysis of Variance; D000779:Anesthetics, Local / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002045:Bupivacaine / Q000494:pharmacology; D002478:Cells, Cultured; D006801:Humans; D015151:Immunoblotting; D020287:In Situ Nick-End Labeling; D007687:Kidney Tubules, Proximal / Q000166:cytology*; D008012:Lidocaine / Q000494:pharmacology; D020928:Mitogen-Activated Protein Kinases / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D013748:Tetracaine / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D000779:Anesthetics, Local; D014409:Tumor Necrosis Factor-alpha; D013748:Tetracaine; D008012:Lidocaine; D020928:Mitogen-Activated Protein Kinases; D002045:Bupivacaine