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1.
Free Radic Biol Med ; 208: 700-707, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37748718

ABSTRACT

INTRODUCTION: Calpain overexpression is implicated in mitochondrial damage leading to tissue oxidative stress and myocardial ischemic injury. The aim of this study was to determine the effects of calpain inhibition (CI) on mitochondrial impairment and oxidative stress in a swine model of chronic myocardial ischemia and metabolic syndrome. METHODS: Yorkshire swine were fed a high-fat diet for 4 weeks to induce metabolic syndrome then underwent placement of an ameroid constrictor to the left circumflex artery. Three weeks later, animals received: no drug (control, "CON"; n= 7); a low-dose calpain inhibitor (0.12 mg/kg; "LCI", n= 7); or high-dose calpain inhibitor (0.25 mg/kg; "HCI", n=7). Treatment continued for 5 weeks, followed by tissue harvest. Cardiac tissue was assayed for protein carbonyl content, as well as antioxidant and mitochondrial protein expression. Reactive oxygen species (ROS) and mitochondrial respiration was measured in H9c2 cells following exposure to normoxia or hypoxia (1%) for 24 h with or without CI. RESULTS: In ischemic myocardial tissue, CI was associated with decreased total oxidative stress compared to control. CI was also associated with increased expression of mitochondrial proteins superoxide dismutase 1, SDHA, and pyruvate dehydrogenase compared to control. 100 nM of calpain inhibitor decreased ROS levels and respiration in both normoxic and hypoxic H9c2 cardiomyoblasts. CONCLUSIONS: In the setting of metabolic syndrome, CI improves oxidative stress in chronically ischemic myocardial tissue. Decreased oxidative stress may be via modulation of mitochondrial proteins involved in free radical scavenging and production.


Subject(s)
Metabolic Syndrome , Myocardial Ischemia , Swine , Animals , Myocardium/metabolism , Calpain/genetics , Calpain/metabolism , Calpain/pharmacology , Metabolic Syndrome/metabolism , Reactive Oxygen Species/metabolism , Protein Carbonylation , Myocardial Ischemia/drug therapy , Myocardial Ischemia/metabolism , Oxidative Stress , Mitochondrial Proteins/metabolism , Disease Models, Animal
3.
Int J Mol Sci ; 24(3)2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36768399

ABSTRACT

We have previously shown that normoxia serum-starved extracellular vesicle (EV) therapy improves myocardial function, perfusion, and angiogenesis in a swine model of chronic myocardial ischemia. Hypoxia-modified EVs have increased abundance of anti-oxidant, pro-angiogenic, and pro-survival proteins. The purpose of this study is to investigate the differential effects of normoxia serum-starved EVs and hypoxia-modified EVs on myocardial function, perfusion, and microvascular density in chronically ischemic myocardium. Yorkshire swine underwent placement of an ameroid constrictor to the left circumflex artery to induce chronic myocardial ischemia. Two weeks later, the pigs underwent intramyocardial injection of either normoxia serum-starved EVs (NOR, n = 10) or hypoxia-modified EVs (HYP, n = 7). Five weeks later, pigs were euthanized, and ischemic myocardium was harvested. Hypoxia EV treatment was associated with improved contractility compared to NOR, as well as improved capillary density, without changes in arteriolar density. There were trends towards improved perfusion at rest and during pacing in the HYP group compared to NOR. Ischemic myocardium in the HYP group had increased pro-angiogenic Akt and ERK signaling and decreased expression of anti-angiogenic markers compared to the NOR group. In the setting of chronic myocardial ischemia, hypoxia-modified EVs may enhance contractility, capillary density, and angiogenic signaling pathways compared to normoxia serum-starved EVs.


Subject(s)
Extracellular Vesicles , Myocardial Ischemia , Swine , Animals , Neovascularization, Physiologic , Coronary Circulation , Myocardial Ischemia/metabolism , Myocardium/metabolism , Hypoxia/metabolism , Perfusion , Extracellular Vesicles/metabolism , Disease Models, Animal
4.
J Thorac Cardiovasc Surg ; 163(1): e11-e27, 2022 01.
Article in English | MEDLINE | ID: mdl-32359903

ABSTRACT

OBJECTIVES: Calpain activation during ischemia is known to play critical roles in myocardial remodeling. We hypothesize that calpain inhibition (CI) may serve to reverse and/or prevent fibrosis in chronically ischemic myocardium. METHODS: Yorkshire swine were fed a high-cholesterol diet for 4 weeks followed by placement of an ameroid constrictor on the left circumflex artery to induce myocardial ischemia. 3 weeks later, animals received either: no drug; high-cholesterol control group (CON; n = 8); low-dose CI (0.12 mg/kg; LCI, n = 9); or high-dose CI (0.25 mg/kg; HCI, n = 8). The high-cholesterol diet and CI were continued for 5 weeks, after which myocardial tissue was harvested. Tissue samples were analyzed by western blot for changes in protein content. RESULTS: In the setting of hypercholesterolemia and chronic myocardial ischemia, CI decreased the expression of collagen in ischemic and nonischemic myocardial tissue. This reduced collagen content was associated with a corresponding decrease in Jak/STAT/MCP-1 signaling pathway, suggesting a role for Jak 2 signaling in calpain activity. CI also decreases the expression of focal adhesion proteins (vinculin) and stabilizes the expression of cytoskeletal and structural proteins (N-cadherin, α-fodrin, desmin, vimentin, filamin, troponin-I). CI had no significant effect on metabolic and hemodynamic parameters. CONCLUSIONS: Calpain inhibition may be a beneficial medical therapy to decrease collagen formation in patients with coronary artery disease and associated comorbidities.


Subject(s)
Calpain/metabolism , Collagen , Glycoproteins/pharmacology , Myocardial Ischemia/metabolism , Myocardium , Ventricular Remodeling , Animals , Chemokine CCL2/metabolism , Collagen/biosynthesis , Collagen/metabolism , Coronary Artery Disease/drug therapy , Coronary Artery Disease/metabolism , Disease Models, Animal , Fibrosis/etiology , Fibrosis/metabolism , Fibrosis/prevention & control , Hypercholesterolemia/metabolism , Janus Kinase 2/metabolism , Myocardium/metabolism , Myocardium/pathology , STAT Transcription Factors/metabolism , Signal Transduction/drug effects , Swine , Ventricular Remodeling/drug effects , Ventricular Remodeling/physiology
5.
J Am Heart Assoc ; 10(4): e017437, 2021 02 16.
Article in English | MEDLINE | ID: mdl-33559477

ABSTRACT

Background Mesenchymal stem cell-derived extracellular vesicles (EVs) promote angiogenesis in the ischemic myocardium. This study examines the difference in vascular density, myocardial perfusion, molecular signaling, and gene expression between normal diet (ND) and high fat diet (HFD) groups at baseline and following intramyocardial injection of EVs. Methods and Results Intact male Yorkshire swine fed either an ND (n=17) or HFD (n=14) underwent placement of an ameroid constrictor on the left circumflex coronary artery. Subsequently, animals received either intramyocardial injection of vehicle-saline as controls; (ND-controls n=7, HFD-controls, n=6) or EVs; (ND-EVs n=10, HFD-EVs n=8) into the ischemic territory. Five weeks later, myocardial function, perfusion, vascular density, cell signaling, and gene expression were examined. EVs improved indices of myocardial contractile function, myocardial perfusion, and arteriogenesis in both dietary cohorts. Interestingly, quantification of alpha smooth muscle actin demonstrated higher basal arteriolar density in HFD swine compared with their ND counterparts; whereas EVs were associated with increased CD31-labeled endothelial cell density only in the ND tissue, which approached significance. Levels of total endothelial nitric oxide synthase, FOXO1 (forkhead box protein O1) , transforming growth factor-ß, phosphorylated VEGFR2 (vascular endothelial growth factor receptor 2), and phosphorylated MAPK ERK1/ERK2 (mitogen-activated protein kinase) were higher in ischemic myocardial lysates from ND-controls compared with HFD-controls. Conversely, HFD-control tissue showed increased expression of phosphorylated endothelial nitric oxide synthase, phosphorylated FOXO1, VEGFR2, and MAPK ERK1/ERK2 with respect to ND-controls. Preliminary gene expression studies indicate differential modulation of transcriptional activity by EVs between the 2 dietary cohorts. Conclusions HFD produces a profound metabolic disorder that dysregulates the molecular mechanisms of collateral vessel formation in the ischemic myocardium, which may hinder the therapeutic angiogenic effects of EVs.


Subject(s)
Angiogenesis Inducing Agents/pharmacology , Coronary Circulation/physiology , Coronary Vessels/diagnostic imaging , Diet, High-Fat/adverse effects , Extracellular Vesicles/pathology , Myocardial Ischemia/etiology , Myocardium/metabolism , Animals , Chronic Disease , Coronary Circulation/drug effects , Coronary Vessels/physiopathology , Disease Models, Animal , Male , Myocardial Ischemia/diagnosis , Myocardial Ischemia/metabolism , Myocardium/pathology , Neovascularization, Pathologic/diagnosis , Neovascularization, Pathologic/etiology , Neovascularization, Pathologic/metabolism , Phosphorylation , Swine
6.
PLoS One ; 15(9): e0238879, 2020.
Article in English | MEDLINE | ID: mdl-32915887

ABSTRACT

BACKGROUND: Mesenchymal stem cell-derived extracellular vesicles (EVs) appear to be a very exciting treatment option for heart disease. Here, we used a swine model of chronic myocardial ischemia to evaluate the efficacy of a less-invasive method of injection of EVs via a peripheral intravenous route. METHODS: Sixteen Yorkshire swine underwent placement of an ameroid constrictor on the left circumflex (LCx) artery at age 11 weeks to induce chronic myocardial ischemia. Two weeks later, they were divided into two groups: control (CON; n = 8), and intravenous injection of EVs (EVIV; n = 8). At 18 weeks of age, animals underwent final analysis and euthanasia. The chronically ischemic myocardium (LCx territory) was harvested for analysis. RESULTS: Intravenous injection (IV) of EVs induced several pro-angiogenic markers such as MAPK, JNK but not Akt. Whereas IV injections of EVs decreased VEGFR2 expression and inhibited apoptotic signaling (caspase 3), they increased expression of VEGFR1 that is believed to be anti-angiogenic. Injection of EVs did not result in an increase in vessel density and blood flow when compared to the control group. CONCLUSIONS: Although IV injection of EVs upregulated several pro-angiogenic signaling pathways, it failed to induce changes in vascular density in the chronically ischemic myocardium. Thus, a lack of increase in vascular density at the doses tested failed to elicit a functional response in ischemic myocardium.


Subject(s)
Disease Models, Animal , Extracellular Vesicles/transplantation , Mesenchymal Stem Cells/cytology , Myocardial Ischemia/therapy , Neovascularization, Physiologic , Animals , Apoptosis , Chronic Disease , Coronary Circulation , Hemodynamics , Humans , Male , Swine
7.
Surgery ; 168(1): 147-154, 2020 07.
Article in English | MEDLINE | ID: mdl-32178865

ABSTRACT

BACKGROUND: Cardiopulmonary bypass may be associated with postoperative neurocognitive dysfunction; however, risk factors have not been clearly identified. We hypothesize that lower hematocrit levels are correlated with postoperative neurocognitive dysfunction. METHODS: A total of 30 patients underwent cardiac operations utilizing cardiopulmonary bypass and screening for neurocognitive dysfunction preoperatively and on postoperative day 4. Patients were analyzed according to hematocrit preoperatively, 6 hours postoperatively, and on postoperative day 4, and whether they received intra or postoperative transfusions of packed red blood cells. Neurocognitive data is presented as a difference in Repeatable Battery for the Assessment of Neuropsychological Status standardized score from baseline to postoperative day 4 and analyzed by unpaired two-tailed Spearman test and unpaired Mann-Whitney U test. RESULTS: There was a significant correlation between patients with lower hematocrit before surgery and a decline in neurocognitive function at postoperative day 4 (P < .05). All patients experienced a decrease in hematocrit during their hospital stay, but the hematocrit 6 hours postoperatively and postoperative day 4 did not impact cognition. Receiving a transfusion was also not associated with neurocognitive dysfunction. Patients with low hematocrit preoperatively had a consistently lower hematocrit throughout their stay. Prolonged total length of stay was also significantly associated with neurocognitive decline. CONCLUSION: A lower preoperative hematocrit and prolonged length of hospital stay are correlated with neurocognitive decline after cardiac surgery utilizing cardiopulmonary bypass.


Subject(s)
Anemia/complications , Cardiopulmonary Bypass/adverse effects , Neurocognitive Disorders/etiology , Postoperative Complications/etiology , Aged , Blood Transfusion, Autologous , Cardiac Surgical Procedures , Female , Hematocrit , Humans , Length of Stay , Male , Middle Aged , Prospective Studies
8.
J Am Heart Assoc ; 8(15): e012617, 2019 08 06.
Article in English | MEDLINE | ID: mdl-31354010

ABSTRACT

Background Ischemic heart disease continues to be a leading cause of mortality in patients. Extracellular vesicles (EVs) provide a potential for treatment that may induce collateral vessel growth to increase myocardial perfusion. Methods and Results Nineteen male Yorkshire pigs were given a high-fat diet for 4 weeks, then underwent placement of an ameroid constrictor on the left circumflex artery to induce chronic myocardial ischemia. Two weeks later, the pigs received either intramyocardial vehicle (n=6), EVs (high-fat diet with myocardial EV injection [HVM]; n=8), or HVM and calpain inhibition (n=5). Five weeks later, myocardial function, perfusion, coronary vascular density, and cell signaling were examined. Perfusion in the collateral-dependent myocardium was increased during rapid ventricular pacing in the HVM group in both nonischemic (P=0.04) and ischemic areas of the ventricle (P=0.05). Cardiac output and stroke volume were significantly improved in the HVM group compared with the control group during ventricular pacing (P=0.006). Increased arteriolar density was seen in the HVM group in both nonischemic and ischemic myocardium (P=0.003 for both). However, no significant changes in the capillary density were observed between the control, HVM, and HVM and calpain inhibition groups (P=0.07). The group that received EVs with oral calpain inhibition had neither increased vessel density (P>0.99) nor improvement in blood flow or cardiac function (P=0.48) when compared with the control group. Conclusions These findings suggest that EVs promote angiogenesis in areas of chronic myocardial ischemia and improve cardiac function under conditions of diet-induced metabolic syndrome.


Subject(s)
Extracellular Vesicles/physiology , Metabolic Syndrome/complications , Myocardial Ischemia/complications , Myocardial Ischemia/therapy , Neovascularization, Physiologic , Animals , Chronic Disease , Disease Models, Animal , Male , Swine
9.
J Am Heart Assoc ; 7(12)2018 06 12.
Article in English | MEDLINE | ID: mdl-29895586

ABSTRACT

BACKGROUND: Mesenchymal stem cell-derived extracellular vesicles (EVs) are believed to be cardioprotective in myocardial infarct. The objective of this study was to examine the effects of human mesenchymal cell-derived EV injection on cardiac function, myocardial blood flow, and vessel density in the setting of chronic myocardial ischemia. METHODS AND RESULTS: Twenty-three Yorkshire swine underwent placement of an ameroid constrictor on their left circumflex artery. Two weeks later, the animals were split into 2 groups: the control group (CON; n=7) and the EV myocardial injection group (MVM; n=10). The MVM group underwent myocardial injection of 50 µg of EVs in 2 mL 0.9% saline into the ischemic myocardium. Five weeks later, the pigs underwent a harvest procedure, and the left ventricular myocardium was analyzed. Absolute blood flow and the ischemic/nonischemic myocardial perfusion ratio were increased in the ischemic myocardium in the MVM group compared with the CON group. Pigs in the MVM group had increased capillary and arteriolar density in the ischemic myocardial tissue compared with CON pigs. There was an increase in expression of the phospho-mitogen-activated protein kinase/mitogen-activated protein kinase ratio, the phospho-endothelial nitric oxide synthase/endothelial nitric oxide synthase ratio, and total protein kinase B in the MVM group compared with CON. There was an increase in cardiac output and stroke volume in the MVM group compared with CON. CONCLUSIONS: In the setting of chronic myocardial ischemia, myocardial injection of human mesenchymal cell-derived EVs increases blood flow to ischemic myocardial tissue by induction of capillary and arteriolar growth via activation of the protein kinase B/endothelial nitric oxide synthase and mitogen-activated protein kinase signaling pathways resulting in increased cardiac output and stroke volume.


Subject(s)
Coronary Circulation , Extracellular Vesicles/transplantation , Hemodynamics , Mesenchymal Stem Cell Transplantation/methods , Myocardial Ischemia/therapy , Neovascularization, Physiologic , Ventricular Function, Left , Animals , Cells, Cultured , Disease Models, Animal , Extracellular Vesicles/metabolism , Humans , Mitogen-Activated Protein Kinases/metabolism , Myocardial Ischemia/metabolism , Myocardial Ischemia/pathology , Myocardial Ischemia/physiopathology , Myocardium/metabolism , Myocardium/pathology , Nitric Oxide Synthase Type III/metabolism , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Recovery of Function , Signal Transduction , Sus scrofa
10.
J Thorac Cardiovasc Surg ; 155(6): 2492-2503, 2018 06.
Article in English | MEDLINE | ID: mdl-29523407

ABSTRACT

OBJECTIVES: Glycogen synthase kinase 3ß (GSK-3ß) inhibition has been reported to increase microvascular density and improve myocardial blood flow in a porcine model of chronic myocardial ischemia and metabolic syndrome. Inhibition of GSK-3ß can also be cardioprotective by modulating fibrosis signaling and mitochondrial-induced apoptosis. We hypothesized GSK-3ß inhibition would have a beneficial effect on myocardial fibrosis and oxidative stress in a porcine model of chronic myocardial ischemia and metabolic syndrome. METHODS: Pigs were fed a high fat diet for 4 weeks followed by placement of an ameroid constrictor to the left circumflex coronary artery. Three weeks later animals received either no drug or a GSK-3ß inhibitor. The diets and placebo/GSK-3ß inhibition were continued for an additional 5 weeks, the pigs were then euthanized, and the myocardial tissue was harvested. Collagen expression was analyzed via Picrosirius staining. Oxidative stress was analyzed via Oxyblot analysis. Protein expression was analyzed via Western blot. RESULTS: GSK-3ß inhibition was associated with decreased collagen expression and oxidative stress in the ischemic and nonischemic myocardial tissue compared with control. There was a decrease in profibrotic proteins transforming growth factor-ß, p-SMAD2/3, and matrix metalloproteinase-9, and in proapoptotic and oxidative stress proteins, apoptosis inducing factor, the cleaved caspase 3/caspase 3 protein ratio and phosphorylated myeloid cell leukemia sequence-1 in the GSK-3ß inhibited group compared with the control. CONCLUSIONS: In the setting of metabolic syndrome and chronic myocardial ischemia, inhibition of GSK-3ß decreases collagen formation and oxidative stress in myocardial tissue. GSK-3ß inhibition might be having this beneficial effect by downregulating transforming growth factor-ß/SMAD2/3 signaling and decreasing mitochondrial induced cellular stress.


Subject(s)
Glycogen Synthase Kinase 3 beta/antagonists & inhibitors , Mitochondria/physiology , Myocardial Ischemia/physiopathology , Oxidative Stress/physiology , Animals , Apoptosis/drug effects , Apoptosis/physiology , Collagen/metabolism , Diet, High-Fat , Glycogen Synthase Kinase 3 beta/metabolism , Metabolic Syndrome/metabolism , Mitochondria/drug effects , Myocardial Ischemia/metabolism , Myocardium/chemistry , Myocardium/enzymology , Myocardium/metabolism , Oxidative Stress/drug effects , Protein Kinase Inhibitors/pharmacology , Swine
11.
J Nat Sci ; 3(6)2017 Jun.
Article in English | MEDLINE | ID: mdl-28758150

ABSTRACT

Cardiac surgery with cardiopulmonary bypass and cardioplegic arrest is associated with injury to the vasculature and microcirculation leading to coronary microvascular dysfunction, permeability changes and cardiac dysfunction. In the setting of cardiopulmonary bypass with cardioplegia, poorly-controlled diabetes is associated with significant changes in endothelium-dependent and independent vascular dysfunction, vascular reactivity, vascular permeability, protein expression, cell death, coronary/peripheral microcirculation and reduced vasomotor tone leading to hypotension and impaired endothelial function. The gene expression profiles after cardiopulmonary bypass with cardioplegic arrest is quantitatively and qualitatively different in patients with diabetes. Gene expression profiling capitalizing on the differences between patients with and without diabetes is a good place to identify potential medical targets.

12.
Coron Artery Dis ; 28(7): 605-613, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28678145

ABSTRACT

Coronary artery disease (CAD) is the number one cause of death among men and women in the USA. Genetic predisposition and environmental factors lead to the development of atherosclerotic plaques in the vessel walls of the coronary arteries, resulting in decreased myocardial perfusion. Treatment includes a combination of revascularization procedures and medical therapy. Because of the high surgical risk of many of the patients undergoing revascularization procedures, medical therapies to reduce ischemic disease are an area of active research. Small molecule, cytokine, endothelial progenitor cell, stem cell, gene, and mechanical therapies show promise in increasing the collateral growth of blood vessels, thereby reducing myocardial ischemia.


Subject(s)
Angiogenesis Inducing Agents/therapeutic use , Coronary Artery Disease/therapy , Coronary Vessels/drug effects , Genetic Therapy/methods , Neovascularization, Physiologic/drug effects , Stem Cell Transplantation/methods , Angiogenesis Inducing Agents/adverse effects , Animals , Collateral Circulation/drug effects , Coronary Artery Disease/genetics , Coronary Artery Disease/metabolism , Coronary Artery Disease/physiopathology , Coronary Circulation/drug effects , Coronary Vessels/metabolism , Coronary Vessels/pathology , Coronary Vessels/physiopathology , Genetic Therapy/adverse effects , Humans , Molecular Targeted Therapy , Neovascularization, Physiologic/genetics , Recovery of Function , Signal Transduction/drug effects , Stem Cell Transplantation/adverse effects , Treatment Outcome
13.
Surgery ; 162(3): 680-687, 2017 09.
Article in English | MEDLINE | ID: mdl-28602493

ABSTRACT

BACKGROUND: Moderate alcohol consumption is cardioprotective but the mechanism of action remains unclear. Nuclear factor κ-B regulates the expression of genes involved in inflammation, stress, and apoptosis. We used a swine model of diet-induced metabolic syndrome to investigate the effects of red wine and vodka on nuclear factor κ-B signaling and cytokine activity in chronically ischemic myocardium. METHODS: Yorkshire swine were given a high-fat diet for 4 weeks; an ameroid constrictor was then placed on the left circumflex artery. The high-fat diet was continued and the swine were divided into 3 groups for 7 weeks: hypercholesterolemic diet alone (control, n = 8), hypercholesterolemic diet with vodka (vodka, n = 8), and hypercholesterolemic diet with wine (wine, n = 8). Ischemic myocardium was analyzed by Western blot and cytokine array. RESULTS: Administration of alcohol was associated with decreased expression of inhibitor of κ-B kinase complex α, inhibitor of κ-B kinase complex ß, and phosphorylated inhibitor of κ-B ß in the ischemic myocardium compared with the control group. Alcohol administration demonstrated an increase in nuclear factor κ-B in the ischemic myocardium. Both wine and vodka demonstrated a significant decrease in leptin, interleukin-1α, IL-13, IL-15, and interferon-γ. Vodka demonstrated a significant decrease in phosphorylated BCL-2 and caspase-9. CONCLUSION: In ischemic myocardium, alcohol modulates the nuclear factor κ-B pathway, which may contribute to the adaptive response of tissues to the stress of ischemia. Furthermore, both wine and vodka decreased multiple proinflammatory cytokines. This study provides a mechanism by which alcohol may be cardioprotective in ischemic myocardium.


Subject(s)
Chemokines/metabolism , Ethanol/administration & dosage , Interleukins/metabolism , Myocardial Ischemia/pathology , Myocardial Ischemia/prevention & control , Animals , Biomarkers/metabolism , Biopsy, Needle , Blotting, Western , Diet, High-Fat , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Immunohistochemistry , Leptin/metabolism , Male , Protein Serine-Threonine Kinases/metabolism , Random Allocation , Sensitivity and Specificity , Swine , Wine , NF-kappaB-Inducing Kinase
14.
Ann Thorac Surg ; 104(2): 431-435, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28527963

ABSTRACT

BACKGROUND: Spontaneous pneumomediastinum (SPM) is classified as free air in the mediastinum in the absence of any precipitating cause. It is relatively uncommon, and the clinical significance and risk associated with SPM is not well understood and has not been widely documented in the literature. Our goals were to determine the outcomes of patients who presented with SPM and to determine predictors of severe pathology associated with SPM. METHODS: From 2004 through 2013, a retrospective review was conducted of patients who presented with SPM to our institution. Patient demographics, comorbidities, laboratory tests, and esophageal perforation were recorded. RESULTS: In all, 249 patients were discovered to have SPM on chest radiograph or computed tomography scan. Mean age was 38.7 years (range, 17 to 81). Sixty-one percent of patients (151 of 249) were male. Ten percent of all patients (24 of 249) were ultimately discovered to have esophageal perforation, determined by upper endoscopy, upper gastrointestinal series, or intraoperatively during emergent surgery. Age (p < 0.01), pleural effusion (p < 0.01), and elevated white blood cell count (p < 0.01) were the only significant risk factors for esophageal perforation on multivariate analysis. CONCLUSIONS: Spontaneous pneumomediastinum is usually associated with a benign clinical course. Risk factors for esophageal perforation in these patients include age, elevated white blood cell count, and a pleural effusion. In the absence of abnormal laboratory values or associated radiologic findings, the majority of patients with SPM may be safely observed without the need for further diagnostic testing.


Subject(s)
Esophageal Perforation/complications , Gastroscopy/adverse effects , Mediastinal Emphysema/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Esophageal Perforation/diagnosis , Female , Follow-Up Studies , Humans , Male , Mediastinal Emphysema/etiology , Mediastinum/injuries , Middle Aged , Radiography, Thoracic , Retrospective Studies , Risk Factors , Tomography, X-Ray Computed , Young Adult
15.
Clin Med Res (N Y) ; 6(6): 173-176, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29683136

ABSTRACT

Perioperative glucose control is highly important, particularly for patients undergoing cardiac surgery. Variable glucose levels before, during and after cardiac surgery lead to increased post-operative complications and patient mortality. [1] Current methods for intensive monitoring and treating hyperglycemia in the Intensive Care Unit (ICU) usually involve hourly glucose monitoring and continuous intravenous insulin infusions. With the advent of more accurate subcutaneous glucose monitoring systems, the role of improved glucose control with newer systems deserves consideration for widespread adoption.

16.
JACC Basic Transl Sci ; 2(3): 328-334, 2017 Jun.
Article in English | MEDLINE | ID: mdl-30062152

ABSTRACT

Taking a solution for a clinical unmet need from a mere idea to a profitable medical device company is a long and complex process. After developing a prototype solution, the physician-inventor must quickly file a patent to protect his or her intellectual property. After the patent is secured, the first major business decision arrives: should the inventor sell the patent or maintain ownership? If the inventor decides to maintain ownership, he or she will face a series of hurdles from obtaining additional funding to device development, and ultimately, commercialization and marketing of the product. Although this process is daunting at first glance, and physicians certainly face unique challenges in this endeavor, clinicians are uniquely and strategically positioned to identify clinical unmet needs and, therefore, have the ability to fundamentally transform the way we treat our patients.

17.
Surgery ; 161(5): 1394-1404, 2017 05.
Article in English | MEDLINE | ID: mdl-28024857

ABSTRACT

BACKGROUND: Emerging data suggest a link between calpain activation and the enhanced inflammatory response of the cardiovascular system. We hypothesize that calpain activation associates with altered inflammatory protein expression in correlation with the proinflammatory profile of the myocardium. Our pig hypercholesterolemic model with chronic myocardial ischemia was treated with calpain inhibitors to establish their potential to improve cardiac function. METHODS: Yorkshire swine, fed a high cholesterol diet for 4 weeks then underwent placement of an ameroid constrictor on the left circumflex artery. Two weeks later, animals received either no drug (high-cholesterol control group, n = 8), a low dose of calpain inhibitors (0.12 mg/kg, n = 9), or a high dose of calpain inhibitors (0.25 mg/kg; n = 8). The high-cholesterol diet and calpain inhibitors were continued for 5 weeks, after which the pig was euthanized. The left ventricular myocardial tissue (ischemic and nonischemic) was harvested and analyzed for inflammatory protein expression. Data were statistically analyzed via the Kruskal-Wallis and Dunn post hoc test. RESULTS: Calpain inhibitor treatment coincides with increased expression of IKB-α and decreased expression of macrophages, NFkB, IL-1, and tumor necrosis factor (TNF)-α in the ischemic myocardial tissue as compared with the control group. An NFkB array revealed decreased expression of IRF5, JNK1/2, JNK2, CD18, NFkB p65, c-Rel, Sharpin, TNF R1, TNF R2, and DR5 in the ischemic myocardium of the group treated with a high dose of calpain inhibitors compared with the control. CONCLUSION: Calpain activation in metabolic syndrome is a potential contributor to cardiac dysfunction in metabolic disorders with ischemic background. We suggest that calpain inhibition downregulates NFkB signaling in the vessel walls, which might be useful for improving myocardial blood flow in ischemic conditions.


Subject(s)
Cysteine Proteinase Inhibitors/therapeutic use , Glycoproteins/therapeutic use , Myocardial Ischemia/drug therapy , Myocardial Ischemia/metabolism , Animals , Chronic Disease , Cytokines/metabolism , Disease Models, Animal , Inflammation Mediators/metabolism , Swine
18.
J Thorac Cardiovasc Surg ; 153(2): 342-357, 2017 02.
Article in English | MEDLINE | ID: mdl-27986275

ABSTRACT

BACKGROUND: Calpain inhibition has an enhancing effect on myocardial perfusion and improves myocardial density by inhibiting glycogen synthase kinase 3ß (GSK-3ß) and up-regulating downstream signaling pathways, including the insulin/PI3K and WNT/ß-catenin pathways, in a pig model of chronic myocardial ischemia in the setting of metabolic syndrome. METHODS: Pigs were fed a high-fat diet for 4 weeks, then underwent placement of an ameroid constrictor to the left circumflex artery. Three weeks later, the animals received no drug (high-cholesterol controls [HCC]), a high-dose calpain inhibitor (HCI), a low-dose calpain inhibitor (LCI), or a GSK-3ß inhibitor (GSK-3ßI). The diets and drug regimens were continued for 5 weeks and the myocardial tissue was harvested. RESULTS: Calpain and GSK-3ß inhibition caused an increase in myocardial perfusion ratios at rest and during pacing compared with controls. Pigs in the LCI and HCI groups had increased vessel density in the ischemic myocardium, and pigs in the GSK-3ßI group had increased vessel density in the ischemic and nonischemic myocardium compared with the HCC group. Calpain inhibition modulates proteins involved in the insulin/PI3K and WNT/ß-catenin pathways. Quantitative proteomics revealed that calpain and GSK-3ß inhibition significantly modulated the expression of proteins enriched in cytoskeletal regulation, metabolism, respiration, and calcium-binding pathways. CONCLUSIONS: In the setting of metabolic syndrome, calpain or GSK-3ß inhibition increases vessel density in both ischemic and nonischemic myocardial tissue. Calpain inhibition may exert these effects through the inhibition of GSK-3ß and up-regulation of downstream signaling pathways, including the insulin/PI3K and WNT/ß-catenin pathways.


Subject(s)
Glycogen Synthase Kinase 3 beta/metabolism , Glycoproteins/pharmacology , Metabolic Syndrome/metabolism , Myocardial Ischemia/metabolism , Myocardium/metabolism , Oxidative Stress , Proteomics/methods , Animals , Apoptosis , Coronary Circulation , Coronary Vessels/physiopathology , Disease Models, Animal , Immunohistochemistry , Metabolic Syndrome/complications , Myocardial Ischemia/etiology , Myocardial Ischemia/pathology , Myocardium/pathology , Signal Transduction , Swine
19.
J Nat Sci ; 2(9)2016.
Article in English | MEDLINE | ID: mdl-27747292

ABSTRACT

Calpains are a 15-member class of calcium activated nonlysosomal neutral proteases which are involved in a broad range of cellular function. Calpains are usually localized to the cytosol and within mitochondria. Calpastatin is an endogenous protein that specifically binds to and inhibits calpain. Overactivation of calpain has been implicated in a number of disease processes of the brain, eyes, heart, lungs, pancreas, kidneys, vascular system and skeletal muscle. Therefore, calpain may serve as a potential therapeutic target for a wide variety of disease processes. This review briefly outlines the current literature regarding the involvement of calpain overactivation in the pathogenesis of almost every organ in the body.

20.
World J Gastrointest Surg ; 8(8): 545-55, 2016 Aug 27.
Article in English | MEDLINE | ID: mdl-27648158

ABSTRACT

Gastric outlet obstruction (GOO) is a common problem associated with advanced malignancies of the upper gastrointestinal tract. Palliative treatment of patients' symptoms who present with GOO is an important aspect of their care. Surgical palliation of malignancy is defined as a procedure performed with the intention of relieving symptoms caused by an advanced malignancy or improving quality of life. Palliative treatment for GOO includes operative (open and laparoscopic gastrojejunostomy) and non-operative (endoscopic stenting) options. The performance status and medical condition of the patient, the extent of the cancer, the patients prognosis, the availability of a curative procedure, the natural history of symptoms of the disease (primary and secondary), the durability of the procedure, and the quality of life and life expectancy of the patient should always be considered when choosing treatment for any patient with advanced malignancy. Gastrojejunostomy appears to be associated with better long term symptom relief while stenting appears to be associated with lower immediate procedure related morbidity.

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