Calpain And Caspase-3 Contribute To Mechanical Ventilation-Induced Diaphragmatic Weakness

Prolonged mechanical ventilation (MV) results in diaphragmatic weakness due to fiber atrophy and contractile dysfunction. Recent work reveals that activation of the proteases calpain and caspase-3 is required for MV-induced diaphragmatic atrophy and contractile dysfunction. However, the mechanism(s) responsible for activation of these proteases remains unknown. To address this issue, we tested the hypothesis that oxidative stress is essential for the activation of calpain and caspase-3 in the diaphragm during MV. Cause-and-effect was established by prevention of MV-induced diaphragmatic oxidative stress using the antioxidant Trolox. Treatment of animals with Trolox prevented MV-induced protein oxidation and lipid peroxidation in the diaphragm. Importantly, the Trolox-mediated protection from MV-induced oxidative stress prevented the activation of calpain and caspase-3 in the diaphragm during MV. Furthermore, the avoidance of MV-induced oxidative stress not only averted the activation of these proteases but also rescued the diaphragm from MV-induced diaphragmatic myofiber atrophy and contractile dysfunction. Collectively, these findings support the prediction that oxidative stress is required for MV-induced activation of calpain and caspase-3 in the diaphragm and are consistent with the concept that antioxidant therapy can retard MV-induced diaphragmatic weakness.

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Toll-like Receptor 4 Signaling in Ventilator-induced Diaphragm Atrophy

Anesthesiology ◽

10.1097/aln.0b013e3182608cc0 ◽

2012 ◽

Vol 117 (2) ◽

pp. 329-338 ◽

Cited By ~ 34

Author(s):

Willem-Jan M. Schellekens ◽

Hieronymus W. H. van Hees ◽

Michiel Vaneker ◽

Marianne Linkels ◽

P. N. Richard Dekhuijzen ◽

...

Keyword(s):

Mechanical Ventilation ◽

Caspase 3 ◽

Toll Like Receptor ◽

Wild Type ◽

Toll Like Receptor 4 ◽

Ubiquitin Proteasome Pathway ◽

Ubiquitin Proteasome ◽

Proteasome Pathway ◽

Diaphragm Atrophy ◽

Deficient Mice

Background Mechanical ventilation induces diaphragm muscle atrophy, which plays a key role in difficult weaning from mechanical ventilation. The signaling pathways involved in ventilator-induced diaphragm atrophy are poorly understood. The current study investigated the role of Toll-like receptor 4 signaling in the development of ventilator-induced diaphragm atrophy. Methods Unventilated animals were selected for control: wild-type (n = 6) and Toll-like receptor 4 deficient mice (n = 6). Mechanical ventilation (8 h): wild-type (n = 8) and Toll-like receptor 4 deficient (n = 7) mice.Myosin heavy chain content, proinflammatory cytokines, proteolytic activity of the ubiquitin-proteasome pathway, caspase-3 activity, and autophagy were measured in the diaphragm. Results Mechanical ventilation reduced myosin content by approximately 50% in diaphragms of wild-type mice (P less than 0.05). In contrast, ventilation of Toll-like receptor 4 deficient mice did not significantly affect diaphragm myosin content. Likewise, mechanical ventilation significantly increased interleukin-6 and keratinocyte-derived chemokine in the diaphragm of wild-type mice, but not in ventilated Toll-like receptor 4 deficient mice. Mechanical ventilation increased diaphragmatic muscle atrophy factor box transcription in both wild-type and Toll-like receptor 4 deficient mice. Other components of the ubiquitin-proteasome pathway and caspase-3 activity were not affected by ventilation of either wild-type mice or Toll-like receptor 4 deficient mice. Mechanical ventilation induced autophagy in diaphragms of ventilated wild-type mice, but not Toll-like receptor 4 deficient mice. Conclusion Toll-like receptor 4 signaling plays an important role in the development of ventilator-induced diaphragm atrophy, most likely through increased expression of cytokines and activation of lysosomal autophagy.

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Calpains play an essential role in mechanical ventilation-induced diaphragmatic weakness and mitochondrial dysfunction

Redox Biology ◽

10.1016/j.redox.2020.101802 ◽

2021 ◽

Vol 38 ◽

pp. 101802

Author(s):

Hayden W. Hyatt ◽

Mustafa Ozdemir ◽

Toshinori Yoshihara ◽

Branden L. Nguyen ◽

Rafael Deminice ◽

...

Keyword(s):

Mechanical Ventilation ◽

Mitochondrial Dysfunction ◽

Essential Role ◽

Diaphragmatic Weakness

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Mechanical ventilation-induced apoptosis in newborn rat lung is mediated via FasL/Fas pathway

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00048.2013 ◽

2013 ◽

Vol 305 (11) ◽

pp. L795-L804 ◽

Cited By ~ 21

Author(s):

Andreas A. Kroon ◽

Veronica DelRiccio ◽

Irene Tseu ◽

Brian P. Kavanagh ◽

Martin Post

Keyword(s):

Mechanical Ventilation ◽

Caspase 3 ◽

Cyclic Stretch ◽

Alveolar Type ◽

Type Ii Cells ◽

Type Ii ◽

Rat Lung ◽

Newborn Rat ◽

Lung Epithelial ◽

Induced Apoptosis

Mechanical ventilation induces pulmonary apoptosis and inhibits alveolar development in preterm infants, but the molecular basis for the apoptotic injury is unknown. The objective was to determine the signaling mechanism(s) of ventilation (stretch)-induced apoptosis in newborn rat lung. Seven-day-old rats were ventilated with room air for 24 h using moderate tidal volumes (8.5 ml/kg). Isolated fetal rat lung epithelial and fibroblast cells were subjected to continuous cyclic stretch (5, 10, or 17% elongation) for up to 12 h. Prolonged ventilation significantly increased the number of apoptotic alveolar type II cells (i.e., terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling and anti-cleaved caspase-3 immunochemistry) and was associated with increased expression of the apoptotic mediator Fas ligand (FasL). Fetal lung epithelial cells, but not fibroblasts, subjected to maximal (i.e., 17%, but not lesser elongation) cyclic stretch exhibited increased apoptosis (i.e., nuclear fragmentation and DNA laddering), which appeared to be mediated via the extrinsic pathway (increased expression of FasL and cleaved caspase-3, -7, and -8). The intrinsic pathway appeared not to be involved [minimal mitochondrial membrane depolarization (JC-1 flow analysis) and no activation of caspase-9]. Universal caspases inhibition and neutralization of FasL abrogated the stretch-induced apoptosis. Prolonged mechanical ventilation induces apoptosis of alveolar type II cells in newborn rats and the mechanism appears to involve activation of the extrinsic death pathway via the FasL/Fas system.

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Xanthine oxidase contributes to mechanical ventilation-induced diaphragmatic oxidative stress and contractile dysfunction

Journal of Applied Physiology ◽

10.1152/japplphysiol.91106.2008 ◽

2009 ◽

Vol 106 (2) ◽

pp. 385-394 ◽

Cited By ~ 67

Author(s):

Melissa A. Whidden ◽

Joseph M. McClung ◽

Darin J. Falk ◽

Matthew B. Hudson ◽

Ashley J. Smuder ◽

...

Keyword(s):

Oxidative Stress ◽

Mechanical Ventilation ◽

Xanthine Oxidase ◽

Prolonged Mechanical Ventilation ◽

Oxidative Injury ◽

Contractile Dysfunction ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Oxidant Production ◽

Diaphragmatic Weakness

Respiratory muscle weakness resulting from both diaphragmatic contractile dysfunction and atrophy has been hypothesized to contribute to the weaning difficulties associated with prolonged mechanical ventilation (MV). While it is clear that oxidative injury contributes to MV-induced diaphragmatic weakness, the source(s) of oxidants in the diaphragm during MV remain unknown. These experiments tested the hypothesis that xanthine oxidase (XO) contributes to MV-induced oxidant production in the rat diaphragm and that oxypurinol, a XO inhibitor, would attenuate MV-induced diaphragmatic oxidative stress, contractile dysfunction, and atrophy. Adult female Sprague-Dawley rats were randomly assigned to one of six experimental groups: 1) control, 2) control with oxypurinol, 3) 12 h of MV, 4) 12 h of MV with oxypurinol, 5) 18 h of MV, or 6) 18 h of MV with oxypurinol. XO activity was significantly elevated in the diaphragm after MV, and oxypurinol administration inhibited this activity and provided protection against MV-induced oxidative stress and contractile dysfunction. Specifically, oxypurinol treatment partially attenuated both protein oxidation and lipid peroxidation in the diaphragm during MV. Further, XO inhibition retarded MV-induced diaphragmatic contractile dysfunction at stimulation frequencies >60 Hz. Collectively, these results suggest that oxidant production by XO contributes to MV-induced oxidative injury and contractile dysfunction in the diaphragm. Nonetheless, the failure of XO inhibition to completely prevent MV-induced diaphragmatic oxidative damage suggests that other sources of oxidant production are active in the diaphragm during prolonged MV.

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Faculty Opinions recommendation of Rapidly progressive diaphragmatic weakness and injury during mechanical ventilation in humans.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.6998956.7201054 ◽

2010 ◽

Author(s):

Christer Sinderby

Keyword(s):

Mechanical Ventilation ◽

Diaphragmatic Weakness

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Caspase activation contributes to endotoxin-induced diaphragm weakness

Journal of Applied Physiology ◽

10.1152/japplphysiol.01288.2005 ◽

2006 ◽

Vol 100 (6) ◽

pp. 1770-1777 ◽

Cited By ~ 62

Author(s):

Gerald S. Supinski ◽

Leigh A. Callahan

Keyword(s):

Caspase 3 ◽

Muscle Force ◽

Caspase Activation ◽

Fluorogenic Substrate ◽

Respiratory Muscle Weakness ◽

Protein Levels ◽

Diaphragmatic Weakness ◽

Caspase Protein ◽

Diaphragm Weakness ◽

Active Caspase

Infections produce significant respiratory muscle weakness, but the mechanisms by which inflammation reduces muscle force remain incompletely understood. Recent work suggests that caspase 3 releases actin and myosin from the contractile protein lattice, so we postulated that infections may reduce skeletal muscle force by activating caspase 3. The present experiments were designed to test this hypothesis by determining 1) diaphragm caspase 3 activation in the diaphragm after endotoxin and 2) the effect of a broad-spectrum caspase inhibitor, Z-Val-Ala-Asp(OCH3)-fluoromethylketone (zVAD-fmk), and a selective caspase 3 inhibitor, N-acetyl-Asp-Glu-Val-Asp-al (DEVD-CHO), on endotoxin-induced diaphragm weakness. Caspase 3 activation was assessed by measuring caspase protein levels and by measuring cleavage of a fluorogenic substrate. Diaphragm force was measured in response to electrical stimulation (1–150 Hz). Caspase-mediated spectrin degradation was assessed by Western blotting. Parameters were compared in mice given saline, endotoxin (12 mg/kg ip), endotoxin plus zVAD-fmk (3 mg/kg iv), zVAD-fmk alone, or endotoxin plus DEVD-CHO (3 mg/kg iv). Endotoxin increased diaphragm active caspase 3 protein ( P < 0.003), increased caspase 3 activity ( P < 0.002), increased diaphragm spectrin degradation ( P < 0.001), and reduced diaphragm force ( P < 0.001). Administration of zVAD-fmk or DEVD-CHO prevented endotoxin-induced weakness (e.g., force in response to 150-Hz stimulation was 23.8 ± 1.4, 12.1 ± 1.3, 23.5 ± 0.8, 22.7 ± 1.3, and 24.4 ± 0.8 N/cm2, respectively, for control, endotoxin, endotoxin plus zVAD-fmk, endotoxin plus DEVD-CHO, and zVAD-fmk alone treated groups, P < 0.001). Caspase inhibitors also prevented spectrin degradation. In conclusion, endotoxin administration elicits significant diaphragm caspase 3 activation and caspase-mediated diaphragmatic weakness.

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