AMP-activated Protein Kinase (AMPK)-dependent and -independent Pathways Regulate Hypoxic Inhibition of Transepithelial Na+ Transport Across Human Airway Epithelial Cells

Overview

Journal Br J Pharmacol

Publisher Wiley

Specialty Pharmacology

Date 2012 Apr 19

PMID 22509822

Citations 14

Authors

C D Tan

R T Smolenski

M I Harhun

H K Patel

S G Ahmed

K Wanisch

R J Yanez-Munoz

D L Baines

Affiliations

Soon will be listed here.

Abstract

Background And Purpose: Pulmonary transepithelial Na(+) transport is reduced by hypoxia, but in the airway the regulatory mechanisms remain unclear. We investigated the role of AMPK and ROS in the hypoxic regulation of apical amiloride-sensitive Na(+) channels and basolateral Na(+) K(+) ATPase activity.

Experimental Approach: H441 human airway epithelial cells were used to examine the effects of hypoxia on Na(+) transport, AMP : ATP ratio and AMPK activity. Lentiviral constructs were used to modify cellular AMPK abundance and activity; pharmacological agents were used to modify cellular ROS.

Key Results: AMPK was activated by exposure to 3% or 0.2% O(2) for 60 min in cells grown in submerged culture or when fluid (0.1 mL·cm(-2) ) was added to the apical surface of cells grown at the air-liquid interface. Only 0.2% O(2) activated AMPK in cells grown at the air-liquid interface. AMPK activation was associated with elevation of cellular AMP:ATP ratio and activity of the upstream kinase LKB1. Hypoxia inhibited basolateral ouabain-sensitive I(sc) (I(ouabain) ) and apical amiloride-sensitive Na(+) conductance (G(Na+) ). Modification of AMPK activity prevented the effect of hypoxia on I(ouabain) (Na(+) K(+) ATPase) but not apical G(Na+) . Scavenging of superoxide and inhibition of NADPH oxidase prevented the effect of hypoxia on apical G(Na+) (epithelial Na(+) channels).

Conclusions And Implications: Hypoxia activates AMPK-dependent and -independent pathways in airway epithelial cells. Importantly, these pathways differentially regulate apical Na(+) channels and basolateral Na(+) K(+) ATPase activity to decrease transepithelial Na(+) transport. Luminal fluid potentiated the effect of hypoxia and activated AMPK, which could have important consequences in lung disease conditions.

Citing Articles

Submersion and hypoxia inhibit alveolar epithelial Na transport through ERK/NF-κB signaling pathway.

Zhou W, Hou Y, Yu T, Wang T, Ding Y, Nie H Respir Res. 2023; 24(1):117.

PMID: 37095538 PMC: 10127099. DOI: 10.1186/s12931-023-02428-z.

Prospective Application of Ferroptosis in Hypoxic Cells for Tumor Radiotherapy.

Su J, Zhao Q, Zheng Z, Wang H, Bian C, Meng L Antioxidants (Basel). 2022; 11(5).

PMID: 35624785 PMC: 9137794. DOI: 10.3390/antiox11050921.

FSH mediates estradiol synthesis in hypoxic granulosa cells by activating glycolytic metabolism through the HIF-1α-AMPK-GLUT1 signaling pathway.

Wu G, Li C, Tao J, Liu Z, Li X, Zang Z J Biol Chem. 2022; 298(5):101830.

PMID: 35300979 PMC: 9036125. DOI: 10.1016/j.jbc.2022.101830.

AMPK-mTOR Signaling and Cellular Adaptations in Hypoxia.

Chun Y, Kim J Int J Mol Sci. 2021; 22(18).

PMID: 34575924 PMC: 8465282. DOI: 10.3390/ijms22189765.

Protective impact of against γ-irradiation and thioacetamide-induced nephrotoxicity in rats mediated by regulation of micro-RNA 1 and micro-RNA 146a.

Salem A, Ismail A Toxicol Res (Camb). 2021; 10(3):453-466.

PMID: 34141159 PMC: 8201556. DOI: 10.1093/toxres/tfab037.

References

Winder W, Wilson H, Hardie D, Rasmussen B, Hutber C, Call G . Phosphorylation of rat muscle acetyl-CoA carboxylase by AMP-activated protein kinase and protein kinase A. J Appl Physiol (1985). 1997; 82(1):219-25. DOI: 10.1152/jappl.1997.82.1.219. View

Verhoeven A, Woods A, Brennan C, Hawley S, Hardie D, Scott J . The AMP-activated protein kinase gene is highly expressed in rat skeletal muscle. Alternative splicing and tissue distribution of the mRNA. Eur J Biochem. 1995; 228(2):236-43. View

Dada L, Chandel N, Ridge K, Pedemonte C, Bertorello A, Sznajder J . Hypoxia-induced endocytosis of Na,K-ATPase in alveolar epithelial cells is mediated by mitochondrial reactive oxygen species and PKC-zeta. J Clin Invest. 2003; 111(7):1057-64. PMC: 152585. DOI: 10.1172/JCI16826. View

Yanez-Munoz R, Balaggan K, Macneil A, Howe S, Schmidt M, Smith A . Effective gene therapy with nonintegrating lentiviral vectors. Nat Med. 2006; 12(3):348-53. DOI: 10.1038/nm1365. View

Emerling B, Weinberg F, Snyder C, Burgess Z, Mutlu G, Viollet B . Hypoxic activation of AMPK is dependent on mitochondrial ROS but independent of an increase in AMP/ATP ratio. Free Radic Biol Med. 2009; 46(10):1386-91. PMC: 3326346. DOI: 10.1016/j.freeradbiomed.2009.02.019. View

Hawley S, Davison M, Woods A, DAVIES S, Beri R, Carling D . Characterization of the AMP-activated protein kinase kinase from rat liver and identification of threonine 172 as the major site at which it phosphorylates AMP-activated protein kinase. J Biol Chem. 1996; 271(44):27879-87. DOI: 10.1074/jbc.271.44.27879. View

Richard K, Ramminger S, Forsyth L, Burchell A, Wilson S . Thyroid hormone potentiates glucocorticoid-evoked airway Na+ transport without affecting alpha-ENaC transcription. FEBS Lett. 2004; 576(3):339-42. DOI: 10.1016/j.febslet.2004.09.030. View

Harhun M, Gordienko D, Kryshtal D, Pucovsky V, Bolton T . Role of intracellular stores in the regulation of rhythmical [Ca2+]i changes in interstitial cells of Cajal from rabbit portal vein. Cell Calcium. 2006; 40(3):287-98. DOI: 10.1016/j.ceca.2006.04.018. View

Yu L, Bao H, Self J, Eaton D, Helms M . Aldosterone-induced increases in superoxide production counters nitric oxide inhibition of epithelial Na channel activity in A6 distal nephron cells. Am J Physiol Renal Physiol. 2007; 293(5):F1666-77. DOI: 10.1152/ajprenal.00444.2006. View

10.

Althaus M, Fronius M, Buchackert Y, Vadasz I, Clauss W, Seeger W . Carbon monoxide rapidly impairs alveolar fluid clearance by inhibiting epithelial sodium channels. Am J Respir Cell Mol Biol. 2009; 41(6):639-50. DOI: 10.1165/rcmb.2008-0458OC. View

11.

Abramov A, Duchen M . Actions of ionomycin, 4-BrA23187 and a novel electrogenic Ca2+ ionophore on mitochondria in intact cells. Cell Calcium. 2003; 33(2):101-12. DOI: 10.1016/s0143-4160(02)00203-8. View

12.

Xie Z, Dong Y, Zhang M, Cui M, Cohen R, Riek U . Activation of protein kinase C zeta by peroxynitrite regulates LKB1-dependent AMP-activated protein kinase in cultured endothelial cells. J Biol Chem. 2006; 281(10):6366-75. DOI: 10.1074/jbc.M511178200. View

13.

Dada L, Sznajder J . Hypoxic inhibition of alveolar fluid reabsorption. Adv Exp Med Biol. 2008; 618:159-68. DOI: 10.1007/978-0-387-75434-5_12. View

14.

Gusarova G, Trejo H, Dada L, Briva A, Welch L, Hamanaka R . Hypoxia leads to Na,K-ATPase downregulation via Ca(2+) release-activated Ca(2+) channels and AMPK activation. Mol Cell Biol. 2011; 31(17):3546-56. PMC: 3165547. DOI: 10.1128/MCB.05114-11. View

15.

Planes C, Blot-Chabaud M, Matthay M, Couette S, Uchida T, Clerici C . Hypoxia and beta 2-agonists regulate cell surface expression of the epithelial sodium channel in native alveolar epithelial cells. J Biol Chem. 2002; 277(49):47318-24. DOI: 10.1074/jbc.M209158200. View

16.

Dull T, Zufferey R, Kelly M, Mandel R, Nguyen M, Trono D . A third-generation lentivirus vector with a conditional packaging system. J Virol. 1998; 72(11):8463-71. PMC: 110254. DOI: 10.1128/JVI.72.11.8463-8471.1998. View

17.

Planes C, Escoubet B, Blot-Chabaud M, Friedlander G, Farman N, Clerici C . Hypoxia downregulates expression and activity of epithelial sodium channels in rat alveolar epithelial cells. Am J Respir Cell Mol Biol. 1997; 17(4):508-18. DOI: 10.1165/ajrcmb.17.4.2680. View

18.

Ramminger S, Baines D, Olver R, Wilson S . The effects of PO2 upon transepithelial ion transport in fetal rat distal lung epithelial cells. J Physiol. 2000; 524 Pt 2:539-47. PMC: 2269884. DOI: 10.1111/j.1469-7793.2000.t01-1-00539.x. View

19.

Grahame Hardie D, Sakamoto K . AMPK: a key sensor of fuel and energy status in skeletal muscle. Physiology (Bethesda). 2006; 21:48-60. DOI: 10.1152/physiol.00044.2005. View

20.

Wilson W, Hawley S, Hardie D . Glucose repression/derepression in budding yeast: SNF1 protein kinase is activated by phosphorylation under derepressing conditions, and this correlates with a high AMP:ATP ratio. Curr Biol. 1996; 6(11):1426-34. DOI: 10.1016/s0960-9822(96)00747-6. View