Abstract
Background
Downregulation of claudin-5 in the heart is associated with the end-stage heart failure.
However, the underlying mechanism ofclaudin-5 is unclear. Here we investigated the
molecular actions of claudin-5 in perspective of mitochondria in cardiomyocytes to
better understand the role of claudin-5 in cardioprotection during ischemia.
Methods
Myocardial ischemia/reperfusion (I/R; 30 min/24 h) and hypoxia/reoxygenation (H/R;
24 h/4 h) were used in this study. Confocal microscopy and transmission electron microscope
(TEM) were used to observe mitochondrial morphology.
Results
Claudin-5 was detected in murine heart tissue and neonatal rat cardiomyocytes (NRCM).
Its protein level was severely decreased after myocardial I/R or H/R. Confocal microscopy
showedclaudin-5 presented in the mitochondria of NRCM. H/R-induced claudin-5 downregulation
was accompanied by mitochondrial fragmentation. The mitofusin 2 (Mfn2) expressionwas
dramatically decreased while the dynamin-related protein (Drp) 1 expression was significantly
increased after H/R. The TEM indicatedH/R-induced mitochondrial swelling and fission.
Adenoviral claudin-5 overexpression reversed these structural disintegration of mitochondria.
The mitochondria-centered intrinsic pathway of apoptosis triggered by H/R and indicated
by the cytochrome c and cleaved caspase 3 in the cytoplasm of NRCMs was also reduced
by overexpressing claudin-5. Claudin-5 overexpression in mouse heart also significantly
decreased cleaved caspase 3 and the infarct size in ischemic heart with improved systolic
function.
Conclusion
We demonstrated for the first time the presence of claudin-5 in the mitochondria in
cardiomyocytes and provided the firm evidence for the cardioprotective role of claudin-5
in the preservation of mitochondrial dynamics and cell fate against hypoxia- or ischemia-induced
stress.
Résumé
Contexte
Une régulation négative de la claudine-5 dans le cœur est associée à l'insuffisance
cardiaque au stade terminal. Cependant, le mécanisme sous-jacent de la claudine-5
n'est pas clair. Nous avons étudié les mécanismes d'actions moléculaires de la claudine-5
dans les mitochondries des cardiomyocytes afin de mieux comprendre le rôle de la claudine-5
dans la cardioprotection pendant l'ischémie.
Méthodes
L'ischémie/reperfusion (I/R; 30 min/24 h) du myocarde et l'hypoxie/régénération (H/R;
24 h/4 h) ont été appliquées lors de cette étude. La microscopie confocale et la microscopie
électronique en transmission (MET) ont été utilisées pour l'observation de la morphologie
des mitochondries.
Résultats
La claudine-5 a été détectée dans le tissu cardiaque murin et dans les cardiomyocytes
néonataux de rat (CNR). Son niveau d'expression protéique était sévérement diminué
après une I/R du myocarde ou une H/R. La microscopie confocale a montré que la claudine-5
était présente dans les mitochondries des CNR. La régulation négative de la claudine-5
induite par l'H/R s'est accompagnée d'une fragmentation mitochondriale. Le niveau
d'expression de la mitofusine-2 (Mfn2) a considérablement diminué tandis que celui
de la protéine de type dynamine-1 (Drp1) a augmenté de manière significative après
l'H/R. La MET a mis en èvidence le gonflement et la fission des mitochondries induits
par l'H/R. La surexpression de la claudine-5 par infection adénovirale a inversé cette
désintégration structurelle des mitochondries. La voie intrinsèque de l'apoptose au
niveau mitochondrial, déclenchée par l'H/R et indiquée par l'expression du cytochrome
c et de la caspase-3 clivée dans le cytoplasme des CNR, a aussi été réduite lors de
la surexpression de la claudine-5. La surexpression de la claudine-5 dans le cœur
de souris a également diminué de manière significative la caspase-3 à l'état clivé
et la taille de l'infarctus dans le cœur ischémique, avec une amélioration de la fonction
systolique.
Conclusion
Nous avons démontré pour la première fois la présence de la claudine-5 dans les mitochondries
des cardiomyocytes et fourni des preuves solides du rôle cardioprotecteur de la claudine-5
dans la préservation de la dynamique mitochondriale et du devenir des cellules opposées
au stress induit par l'hypoxie ou l'ischémie.
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to Canadian Journal of CardiologyAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Biology of claudins.Am J Physiol Renal Physiol. 2008; 295: F867-F876
- Endothelial adherens junctions control tight junctions by VE-cadherin–mediated upregulation of claudin-5.Nat Cell Biol. 2008; 10: 923-934
- Cerebralcare Granule® attenuates blood-brain barrier disruption after middle cerebral artery occlusion in rats.Exp Neurol. 2012; 237: 453-463
- Hydrocortisone enhances the function of the blood-nerve barrier through the up-regulation of claudin-5.Neurochem Res. 2011; 36: 849-855
- Baicalin reduces the permeability of the blood-brain barrier during hypoxia in vitro by increasing the expression of tight junction proteins in brain microvascular endothelial cells.J Ethnopharmacol. 2012; 141: 714-720
- Claudin-5 as a novel estrogen target in vascular endothelium.Arterioscler Thromb Vasc Biol. 2010; 30: 298-304
- Claudin5 genes encoding tight junction proteins are required for Xenopus heart formation.Dev Growth Differ. 2010; 52: 665-675
- Claudin-5 levels are reduced in human end-stage cardiomyopathy.J Mol Cell Cardiol. 2008; 45: 81-87
- Claudin-5 localizes to the lateral membranes of cardiomyocytes and is altered in utrophin/dystrophin-deficient cardiomyopathic mice.J Mol Cell Cardiol. 2005; 38: 323-332
- Claudin-5 levels are reduced from multiple cell types in human failing hearts and are associated with mislocalization of ephrin-B1.Cardiovasc Pathol. 2015; 24: 160-167
- Sustaining cardiac claudin-5 levels prevents functional hallmarks of cardiomyopathy in a muscular dystrophy mouse model.Mol Ther. 2012; 20: 1378-1383
- Mitochondrial dynamics: an emerging paradigm in ischemia-reperfusion injury.Curr Pharm Des. 2013; 19: 6848-6857
- Mitochondria in heart failure: the emerging role of mitochondrial dynamics.Heart Fail Rev. 2013; 18: 439-456
- Molecular regulation of mitochondrial dynamics in cardiac disease.Biochim Biophys Acta. 2017; 1864: 1260-1273
- Mitochondrial fission/fusion and cardiomyopathy.Curr Opin Genet Dev. 2016; 38: 38-44
- Mitochondrial dynamism and heart disease: changing shape and shaping change.EMBO Mol Med. 2015; 7: 865-877
- Mitochondrial dynamics in heart disease.Biochim Biophys Acta. 2013; 1833: 233-241
- Contribution of claudin-5 to barrier properties in tight junctions of epithelial cells.Cell Tissue Res. 2005; 321: 89-96
- Histamine H2 receptor activation exacerbates myocardial ischemia/reperfusion injury by disturbing mitochondrial and endothelial function.Basic Res Cardiol. 2013; 108: 342
- Mitochondrial p38beta and manganese superoxide dismutase interaction mediated by estrogen in cardiomyocytes.PLoS One. 2014; 9: e85272
- Oestrogen prevents cardiomyocyte apoptosis by suppressing p38α-mediated activation of p53 and by down-regulating p53 inhibition on p38β.Cardiovasc Res. 2011; 89: 119-128
- Attenuation of ER stress prevents post-infarction-induced cardiac rupture and remodeling by modulating both cardiac apoptosis and fibrosis.Chem Biol Interact. 2015; 225: 90-98
- Estrogen protects the female heart from ischemia/reperfusion injury through manganese superoxide dismutase phosphorylation by mitochondrial p38β at threonine 79 and serine 106.PLoS One. 2016; 11e0167761
- Claudin-5 expression in the vasculature of the developing chick embryo.Gene Expr Patterns. 2012; 12: 123-129
- Disruption of fusion results in mitochondrial heterogeneity and dysfunction.J Biol Chem. 2005; 280: 26185-26192
- The role of dynamin-related protein 1, a mediator of mitochondrial fission, in apoptosis.Dev Cell. 2001; 1: 515-525
- The roles of claudin superfamily proteins in paracellular transport.Traffic. 2001; 2: 93-98
- Structural evidence for a new elaborate 3D-organization of the cardiomyocyte lateral membrane in adult mammalian cardiac tissues.Cardiovasc Res. 2019; 115: 1078-1091
- Mitochondrial, sarcoplasmic membrane integrity and protein degradation in heart and skeletal muscle in exercised rats.Comp Biochem Physiol C Toxicol Pharmacol. 2003; 134: 199-206
- Phosphorylation of claudin-3 at threonine 192 by cAMP-dependent protein kinase regulates tight junction barrier function in ovarian cancer cells.J Biol Chem. 2005; 280: 26233-26240
- PKC and PKA phosphorylation affect the subcellular localization of claudin-1 in melanoma cells.Int J Med Sci. 2009; 6: 93-101
- Organization of choroid plexus epithelial and endothelial cell tight junctions and regulation of claudin-1, -2 and -5 expression by protein kinase C.Neuroreport. 2000; 11: 1427-1431
- Mitochondrial fusion is essential for organelle function and cardiac homeostasis.Circ Res. 2011; 109: 1327-1331
- Doxorubicin-induced cardiomyocyte apoptosis: role of mitofusin 2.Int J Biochem Cell Biol. 2017; 88: 55-59
- Mitochondrial fission in apoptosis.Nature reviews. Mol Cell Biol. 2005; 6: 657-663
- Mitochondrial dynamics—mitochondrial fission and fusion in human diseases.N Engl J Med. 2013; 369: 2236-2251
- Acute inhibition of excessive mitochondrial fission after myocardial infarction prevents long-term cardiac dysfunction.J Am Heart Assoc. 2013; 2e000461
- Inhibiting mitochondrial fission protects the heart against ischemia/reperfusion injury.Circulation. 2010; 121: 2012-2022
- Dynamin-related protein 1 (Drp1)–mediated diastolic dysfunction in myocardial ischemia-reperfusion injury: therapeutic benefits of Drp1 inhibition to reduce mitochondrial fission.FASEB J. 2014; 28: 316-326
- Ischemia-induced Drp1 and Fis1–mediated mitochondrial fission and right ventricular dysfunction in pulmonary hypertension.J Mol Med. 2017; 95: 381-393
- Inhibition of dynamin-related protein 1 protects against myocardial ischemia-reperfusion injury in diabetic mice.Cardiovasc Diabetol. 2017; 16: 19
- Dysregulation of Mfn2 and Drp-1 proteins in heart failure.Can J Physiol Pharmacol. 2014; 92: 583-591
- Significance of mitochondrial protein post-translational modifications in pathophysiology of brain injury.Transl Stroke Res. 2018; 9: 223-237
Article info
Publication history
Published online: April 07, 2021
Accepted:
March 29,
2021
Received:
December 18,
2019
Footnotes
See page 1605 for disclosure information.
Identification
Copyright
© 2021 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
