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Kane MS, Juncos JXM, Manzoor S, Grenett M, Oh JY, Pat B, Ahmed MI, Lewis C, Davies JE, Denney TS, McConathy J, Dell’Italia LJ. Gene expression and ultra-structural evidence for metabolic derangement in the primary mitral regurgitation heart. EUROPEAN HEART JOURNAL OPEN 2024; 4:oeae034. [PMID: 38854954 PMCID: PMC11157345 DOI: 10.1093/ehjopen/oeae034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 03/29/2024] [Accepted: 04/22/2024] [Indexed: 06/11/2024]
Abstract
Aims Chronic neurohormonal activation and haemodynamic load cause derangement in the utilization of the myocardial substrate. In this study, we test the hypothesis that the primary mitral regurgitation (PMR) heart shows an altered metabolic gene profile and cardiac ultra-structure consistent with decreased fatty acid and glucose metabolism despite a left ventricular ejection fraction (LVEF) > 60%. Methods and results Metabolic gene expression in right atrial (RA), left atrial (LA), and left ventricular (LV) biopsies from donor hearts (n = 10) and from patients with moderate-to-severe PMR (n = 11) at surgery showed decreased mRNA glucose transporter type 4 (GLUT4), GLUT1, and insulin receptor substrate 2 and increased mRNA hexokinase 2, O-linked N-acetylglucosamine transferase, and O-linked N-acetylglucosaminyl transferase, rate-limiting steps in the hexosamine biosynthetic pathway. Pericardial fluid levels of neuropeptide Y were four-fold higher than simultaneous plasma, indicative of increased sympathetic drive. Quantitative transmission electron microscopy showed glycogen accumulation, glycophagy, increased lipid droplets (LDs), and mitochondrial cristae lysis. These findings are associated with increased mRNA for glycogen synthase kinase 3β, decreased carnitine palmitoyl transferase 2, and fatty acid synthase in PMR vs. normals. Cardiac magnetic resonance and positron emission tomography for 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) uptake showed decreased LV [18F]FDG uptake and increased plasma haemoglobin A1C, free fatty acids, and mitochondrial damage-associated molecular patterns in a separate cohort of patients with stable moderate PMR with an LVEF > 60% (n = 8) vs. normal controls (n = 8). Conclusion The PMR heart has a global ultra-structural and metabolic gene expression pattern of decreased glucose uptake along with increased glycogen and LDs. Further studies must determine whether this presentation is an adaptation or maladaptation in the PMR heart in the clinical evaluation of PMR.
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Affiliation(s)
- Mariame Selma Kane
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
- Birmingham Veterans Affairs Health Care System, 700 South 19th Street, Birmingham, AL 35233, USA
| | - Juan Xavier Masjoan Juncos
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
| | - Shajer Manzoor
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
| | - Maximiliano Grenett
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
| | - Joo-Yeun Oh
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
- Birmingham Veterans Affairs Health Care System, 700 South 19th Street, Birmingham, AL 35233, USA
| | - Betty Pat
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
- Birmingham Veterans Affairs Health Care System, 700 South 19th Street, Birmingham, AL 35233, USA
| | - Mustafa I Ahmed
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
- Division of Thoracic and Cardiovascular Surgery, Department of Surgery, University of Alabama at Birmingham (UAB), 1808 7th Avenue, Birmingham, AL 35294, USA
| | - Clifton Lewis
- Division of Thoracic and Cardiovascular Surgery, Department of Surgery, University of Alabama at Birmingham (UAB), 1808 7th Avenue, Birmingham, AL 35294, USA
| | - James E Davies
- Division of Thoracic and Cardiovascular Surgery, Department of Surgery, University of Alabama at Birmingham (UAB), 1808 7th Avenue, Birmingham, AL 35294, USA
| | - Thomas S Denney
- Samuel Ginn College of Engineering, Auburn University, 345 W Magnolia Ave, Auburn, AL 36849, USA
| | - Jonathan McConathy
- Department of Radiology, University of Albama (UAB), 619 19th Street South, Birmingham, AL 35294, USA
| | - Louis J Dell’Italia
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham (UAB), 1900 University Boulevard, Birmingham, AL 35233, USA
- Birmingham Veterans Affairs Health Care System, 700 South 19th Street, Birmingham, AL 35233, USA
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Manzoor S, Kane MS, Grenett M, Oh JY, Pat B, Lewis C, Davies JE, Steele C, Patel RP, Dell'Italia LJ. Elevated cardiac hemoglobin expression is associated with a pro-oxidative and inflammatory environment in primary mitral regurgitation. Free Radic Biol Med 2023; 208:126-133. [PMID: 37543167 DOI: 10.1016/j.freeradbiomed.2023.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 08/07/2023]
Abstract
BACKGROUND Primary mitral regurgitation (PMR) is associated with oxidative and inflammatory myocardial damage. We reported greater exosome hemoglobin (Hb) in pericardial fluid (PCF) versus plasma, suggesting a cardiac source of Hb. OBJECTIVE Test the hypothesis that Hb is produced in the PMR heart and is associated with increased inflammation. METHODS AND RESULTS Hb gene expression for subunits alpha (HBA) and beta (HBB) was assessed in right atria (RA), left atria (LA) and left ventricular (LV) tissue from donor hearts (n = 10) and PMR patient biopsies at surgery (n = 11). PMR patients (n = 22) had PCF and blood collected for macrophage markers, pro-inflammatory cytokines, and matrix metalloproteinases (MMPs). In-situ hybridization for HBA mRNA and immunohistochemistry for Hb-alpha (Hbα) and Hb-beta (Hbβ) protein was performed on PMR tissue. RESULTS HBA and HBB genes are significantly increased (>4-fold) in RA, LA, and LV in PMR vs. normal hearts. In PMR tissue, HBA mRNA is expressed in both LV cardiomyocytes and interstitial cells by in-situ hybridization; however, Hbα and Hbβ protein is only expressed in interstitial cells by immunohistochemistry. PCF oxyHb is significantly increased over plasma along with low ratios (<1.0) of haptoglobin:oxyHb and hemopexin:heme supporting a highly oxidative environment. Macrophage chemotactic protein-1, tumor necrosis factor-α, interleukin-6, and MMPs are significantly higher in PCF vs. plasma. CONCLUSION There is increased Hb production in the PMR heart coupled with the inflammatory state of the heart, suggests a myocardial vulnerability of further Hb delivery and/or production during cardiac surgery that could adversely affect LV functional recovery.
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Affiliation(s)
- Shajer Manzoor
- Department of Medicine, Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Mariame Selma Kane
- Department of Medicine, Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA; Birmingham Veterans Affairs Health Care System, Birmingham, AL, USA
| | - Maximiliano Grenett
- Department of Medicine, Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA; Birmingham Veterans Affairs Health Care System, Birmingham, AL, USA
| | - Joo-Yeun Oh
- Department of Medicine, Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA; Birmingham Veterans Affairs Health Care System, Birmingham, AL, USA
| | - Betty Pat
- Department of Medicine, Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA; Birmingham Veterans Affairs Health Care System, Birmingham, AL, USA
| | - Clifton Lewis
- Department of Surgery, Division of Thoracic and Cardiovascular Surgery, UAB, USA
| | - James E Davies
- Department of Surgery, Division of Thoracic and Cardiovascular Surgery, UAB, USA
| | - Chad Steele
- Department of Microbiology and Immunology, Tulane University, New Orleans, LA, USA
| | - Rakesh P Patel
- Department of Pathology and Center for Free Radical Biology, UAB, USA
| | - Louis J Dell'Italia
- Department of Medicine, Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA; Birmingham Veterans Affairs Health Care System, Birmingham, AL, USA.
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Dell'Italia LJ, Ahmed MI. Time to Connect Pathophysiology and State-of-the-Art Imaging. JACC Clin Electrophysiol 2023; 9:1717-1718. [PMID: 37648341 DOI: 10.1016/j.jacep.2023.05.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 05/13/2023] [Indexed: 09/01/2023]
Affiliation(s)
- Louis J Dell'Italia
- Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, Alabama, USA; Birmingham Veterans Affairs Health Care System, Birmingham, Alabama, USA.
| | - Mustafa I Ahmed
- Division of Cardiology, University of Alabama at Birmingham (UAB), Birmingham, Alabama, USA
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Zheng J, Li Y, Billor N, Ahmed MI, Fang YHD, Pat B, Denney TS, Dell’Italia LJ. Understanding post-surgical decline in left ventricular function in primary mitral regurgitation using regression and machine learning models. Front Cardiovasc Med 2023; 10:1112797. [PMID: 37153472 PMCID: PMC10160646 DOI: 10.3389/fcvm.2023.1112797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 03/28/2023] [Indexed: 05/09/2023] Open
Abstract
Background Class I echocardiographic guidelines in primary mitral regurgitation (PMR) risks left ventricular ejection fraction (LVEF) < 50% after mitral valve surgery even with pre-surgical LVEF > 60%. There are no models predicting LVEF < 50% after surgery in the complex interplay of increased preload and facilitated ejection in PMR using cardiac magnetic resonance (CMR). Objective Use regression and machine learning models to identify a combination of CMR LV remodeling and function parameters that predict LVEF < 50% after mitral valve surgery. Methods CMR with tissue tagging was performed in 51 pre-surgery PMR patients (median CMR LVEF 64%), 49 asymptomatic (median CMR LVEF 63%), and age-matched controls (median CMR LVEF 64%). To predict post-surgery LVEF < 50%, least absolute shrinkage and selection operator (LASSO), random forest (RF), extreme gradient boosting (XGBoost), and support vector machine (SVM) were developed and validated in pre-surgery PMR patients. Recursive feature elimination and LASSO reduced the number of features and model complexity. Data was split and tested 100 times and models were evaluated via stratified cross validation to avoid overfitting. The final RF model was tested in asymptomatic PMR patients to predict post-surgical LVEF < 50% if they had gone to mitral valve surgery. Results Thirteen pre-surgery PMR had LVEF < 50% after mitral valve surgery. In addition to LVEF (P = 0.005) and LVESD (P = 0.13), LV sphericity index (P = 0.047) and LV mid systolic circumferential strain rate (P = 0.024) were predictors of post-surgery LVEF < 50%. Using these four parameters, logistic regression achieved 77.92% classification accuracy while RF improved the accuracy to 86.17%. This final RF model was applied to asymptomatic PMR and predicted 14 (28.57%) out of 49 would have post-surgery LVEF < 50% if they had mitral valve surgery. Conclusions These preliminary findings call for a longitudinal study to determine whether LV sphericity index and circumferential strain rate, or other combination of parameters, accurately predict post-surgical LVEF in PMR.
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Affiliation(s)
- Jingyi Zheng
- Department of Mathematics and Statistics, Auburn University, Auburn, AL, United States
| | - Yuexin Li
- Department of Mathematics and Statistics, Auburn University, Auburn, AL, United States
| | - Nedret Billor
- Department of Mathematics and Statistics, Auburn University, Auburn, AL, United States
| | - Mustafa I. Ahmed
- Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Yu-Hua Dean Fang
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Betty Pat
- Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, AL, United States
- Birmingham Veterans Affairs Health Care System, Birmingham, AL, United States
| | - Thomas S. Denney
- Department of Electrical and Computer Engineering, Samuel Ginn College of Engineering, Auburn University, Auburn, AL, United States
| | - Louis J. Dell’Italia
- Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, AL, United States
- Birmingham Veterans Affairs Health Care System, Birmingham, AL, United States
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Ahmed MI, Andrikopoulou E, Zheng J, Ulasova E, Pat B, Kelley EE, Powell PC, Denney TS, Lewis C, Davies JE, Darley-Usmar V, Dell’Italia LJ. Interstitial Collagen Loss, Myocardial Remodeling, and Function in Primary Mitral Regurgitation. JACC Basic Transl Sci 2022; 7:973-981. [PMID: 36337921 PMCID: PMC9626893 DOI: 10.1016/j.jacbts.2022.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/27/2022] [Accepted: 04/27/2022] [Indexed: 11/12/2022]
Abstract
The stretch of volume overload in PMR initiates interstitial collagen loss and decrease in LV sphericity index. LV chamber diastolic function is normal whereas LA function, LV twist/volume slope, early LV untwist, and myocardial circumferential strain are impaired. There is increased oxidative stress in the cardiomyocyte with cytoskeletal breakdown and myofibrillar loss in PMR.
Interstitial collagen loss and cardiomyocyte ultrastructural damage accounts for left ventricular (LV) sphericity and decrease in LV twist and circumferential strain. Normal LV diastolic function belies significantly abnormal left atrial (LA) function and early LV diastolic untwist rate. This underscores the complex interplay of LV and LA myocardial remodeling and function in the pathophysiology of primary mitral regurgitation. In this study, we connect LA function with LV systolic and diastolic myocardial remodeling and function using cardiac magnetic resonance tissue tagging in primary mitral regurgitation.
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Butts B, Ahmed MI, Bajaj NS, Cox Powell P, Pat B, Litovsky S, Gupta H, Lloyd SG, Denney TS, Zhang X, Aban I, Sadayappan S, McNamara JW, Watson MJ, Ferrario CM, Collawn JF, Lewis C, Davies JE, Dell'Italia LJ. Reduced Left Atrial Emptying Fraction and Chymase Activation in Pathophysiology of Primary Mitral Regurgitation. JACC Basic Transl Sci 2020; 5:109-122. [PMID: 32140620 PMCID: PMC7046515 DOI: 10.1016/j.jacbts.2019.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/04/2019] [Accepted: 11/04/2019] [Indexed: 11/17/2022]
Abstract
Increasing left atrial (LA) size predicts outcomes in patients with isolated mitral regurgitation (MR). Chymase is plentiful in the human heart and affects extracellular matrix remodeling. Chymase activation correlates to LA fibrosis, LA enlargement, and a decreased total LA emptying fraction in addition to having a potential intracellular role in mediating myofibrillar breakdown in LA myocytes. Because of the unreliability of the left ventricular ejection fraction in predicting outcomes in MR, LA size and the total LA emptying fraction may be more suitable indicators for timing of surgical intervention.
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Affiliation(s)
- Brittany Butts
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
| | - Mustafa I Ahmed
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
| | - Navkaranbir S Bajaj
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
| | - Pamela Cox Powell
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
| | - Betty Pat
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
| | - Silvio Litovsky
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Himanshu Gupta
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Veterans Affairs Medical Center, Birmingham, Alabama
- Department of Cardiology, Valley Health System, Paramus, New Jersey
| | - Steven G Lloyd
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Veterans Affairs Medical Center, Birmingham, Alabama
| | - Thomas S Denney
- Department of Electrical and Computer Engineering, Auburn University School of Engineering, Auburn, Alabama
| | - Xiaoxia Zhang
- Department of Electrical and Computer Engineering, Auburn University School of Engineering, Auburn, Alabama
| | - Inmaculada Aban
- Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama
| | - Sakthivel Sadayappan
- Division of Cardiovascular Disease, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - James W McNamara
- Division of Cardiovascular Disease, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Michael J Watson
- Division of Cardiothoracic Surgery, Department of Surgery, Duke University, Durham, North Carolina
| | - Carlos M Ferrario
- Department of Surgery, Wake Forest University Health Science Center, Winston-Salem, North Carolina
| | - James F Collawn
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Clifton Lewis
- Department of Surgery, Division of Thoracic and Cardiovascular Surgery, University of Alabama at Birmingham, Birmingham, Alabama
| | - James E Davies
- Department of Surgery, Division of Thoracic and Cardiovascular Surgery, University of Alabama at Birmingham, Birmingham, Alabama
| | - Louis J Dell'Italia
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Veterans Affairs Medical Center, Birmingham, Alabama
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Global longitudinal strain: is it a superior assessment method for left ventricular function in patients with chronic mitral regurgitation undergoing mitral valve replacement? Indian J Thorac Cardiovasc Surg 2019; 36:119-126. [PMID: 33061110 DOI: 10.1007/s12055-019-00854-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/27/2019] [Accepted: 07/18/2019] [Indexed: 12/14/2022] Open
Abstract
Purpose Left ventricular ejection fraction may remain normal or even higher despite significant impairment of contractility in cases of mitral regurgitation. The aim of this study is to evaluate the changes in left ventricular function after mitral valve replacement and to study the role of global longitudinal strain in detecting early left ventricular dysfunction using speckle tracking. Method Study involved 31 patients who underwent mitral valve replacement for mitral regurgitation. Patient's preoperative and postoperative echocardiography (conventional parameters and global longitudinal strain) and other parameters like functional status, radiological findings, and electrocardiogram were recorded to evaluate left ventricular function. Results All patients presented in advanced stage with New York heart association class III (67.7%) and IV (32.3%). There was significant decline in left ventricular ejection fraction (with the mean value from 64.58 to 40.13%) and global longitudinal strain (- 15.57 ± 4.98to - 8.97) in the immediate postoperative period (~ 7 days). However, there was a rise in both left ventricular ejection fraction (mean 52.48%) and in global longitudinal strain (mean - 14.44 ± 3.67) at 3 months. Left ventricular and atrial size decreased significantly immediately after surgery, which further declined at 3 months. We also found that patients who attained a left ventricular ejection fraction of > 50% in postoperative period had better left ventricular ejection fraction and global longitudinal strain preoperatively. In addition, they had smaller cardiac size and milder pulmonary hypertension comparatively. Conclusions Mitral valve replacement in mitral regurgitation results in decline in left ventricular function immediately after surgery. In patients with chronic mitral regurgitation, left ventricular ejection fraction is fallacious and global longitudinal strain can be an important tool to assess left ventricular ejection fraction.
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Guichard JL, Rogowski M, Agnetti G, Fu L, Powell P, Wei CC, Collawn J, Dell'Italia LJ. Desmin loss and mitochondrial damage precede left ventricular systolic failure in volume overload heart failure. Am J Physiol Heart Circ Physiol 2017; 313:H32-H45. [PMID: 28455287 PMCID: PMC5538858 DOI: 10.1152/ajpheart.00027.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/27/2017] [Accepted: 04/10/2017] [Indexed: 01/10/2023]
Abstract
Heart failure due to chronic volume overload (VO) in rats and humans is characterized by disorganization of the cardiomyocyte desmin/mitochondrial network. Here, we tested the hypothesis that desmin breakdown is an early and continuous process throughout VO. Male Sprague-Dawley rats had aortocaval fistula (ACF) or sham surgery and were examined 24 h and 4 and 12 wk later. Desmin/mitochondrial ultrastructure was examined by transmission electron microscopy (TEM) and immunohistochemistry (IHC). Protein and kinome analysis were performed in isolated cardiomyocytes, and desmin cleavage was assessed by mass spectrometry in left ventricular (LV) tissue. Echocardiography demonstrated a 40% decrease in the LV mass-to-volume ratio with spherical remodeling at 4 wk with ACF and LV systolic dysfunction at 12 wk. Starting at 24 h and continuing to 4 and 12 wk, with ACF there is TEM evidence of extensive mitochondrial clustering, IHC evidence of disorganization associated with desmin breakdown, and desmin protein cleavage verified by Western blot analysis and mass spectrometry. IHC results revealed that ACF cardiomyocytes at 4 and 12 wk had perinuclear translocation of αB-crystallin from the Z disk with increased α, β-unsaturated aldehyde 4-hydroxynonelal. Use of protein markers with verification by TUNEL staining and kinome analysis revealed an absence of cardiomyocyte apoptosis at 4 and 12 wk of ACF. Significant increases in protein indicators of mitophagy were countered by a sixfold increase in p62/sequestosome-1, which is indicative of an inability to complete autophagy. An early and continuous disruption of the desmin/mitochondrial architecture, accompanied by oxidative stress and inhibition of apoptosis and mitophagy, suggests its causal role in LV dilatation and systolic dysfunction in VO.NEW & NOTEWORTHY This study provides new evidence of early onset (24 h) and continuous (4-12 wk) desmin misarrangement and disruption of the normal sarcomeric and mitochondrial architecture throughout the progression of volume overload heart failure, suggesting a causal link between desmin cleavage and mitochondrial disorganization and damage.
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Affiliation(s)
- Jason L Guichard
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama.,Center for Heart Failure Research, University of Alabama at Birmingham, Birmingham, Alabama
| | - Michael Rogowski
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama.,Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Giulio Agnetti
- Division of Cardiology, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland.,Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy; and
| | - Lianwu Fu
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Pamela Powell
- Department of Veterans Affairs Medical Center, Birmingham, Alabama
| | - Chih-Chang Wei
- Center for Heart Failure Research, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Veterans Affairs Medical Center, Birmingham, Alabama
| | - James Collawn
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Louis J Dell'Italia
- Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama; .,Center for Heart Failure Research, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Veterans Affairs Medical Center, Birmingham, Alabama
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