Inflammation and a metabolic shift from oxidative metabolism to glycolysis are common in the ischemic heart, the latter partly controlled by pyruvate kinase (muscle, PKM). We previously identified alternative splicing promoting the PKM2 isoform after myocardial infarction (MI). We examined the role of PKM2 physiological upregulation after MI, modeled by ligation of the left anterior descending coronary artery, using global PKM2 knockout (PKM2) mice.
View Article and Find Full Text PDFCRISPR-Cas9-based genome editing technologies, such as base editing, have the potential for clinical translation, but delivering nucleic acids into target cells is a major obstacle. Viral vectors are widely used but come with safety concerns, while current non-viral methods are limited by low transfection efficiency. Here we describe a new method to deliver CRISPR-Cas9 base editing vectors to the mouse liver using focused ultrasound targeted microbubble destruction (FUTMD).
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
December 2022
Many anticancer therapies cause serious cardiovascular complications that degrade quality of life and cause early mortality in treated patients. Specifically, doxorubicin is known as an effective anticancer agent that causes cardiomyopathy in treated patients. There has been growing interest in defining the role of endothelial cells in cardiac damage by doxorubicin.
View Article and Find Full Text PDFBackground: The GenTAC (Genetically Triggered Thoracic Aortic Aneurysm and Cardiovascular Conditions) Registry enrolled patients with genetic aortopathies between 2007 and 2016.
Objectives: The purpose of this study was to compare age distribution and probability of elective surgery for proximal aortic aneurysm, any dissection surgery, and cardiovascular mortality among aortopathy etiologies.
Methods: The GenTAC study had a retrospective/prospective design.
The heart forms early in development and delivers oxygenated blood to the rest of the embryo. After birth, the heart requires kilograms of ATP each day to support contractility for the circulation. Cardiac metabolism is omnivorous, utilizing multiple substrates and metabolic pathways to produce this energy.
View Article and Find Full Text PDFIschemic heart disease is a leading cause of heart failure and hypoxia inducible factor 1 (HIF1) is a key transcription factor in the response to hypoxic injury. Our lab has developed a mouse model in which a mutated, oxygen-stable form of HIF1α (HIF-PPN) can be inducibly expressed in cardiomyocytes. We observed rapid cardiac dilation and loss of contractility in these mice due to lower expression of excitation-contraction coupling genes and reduced calcium flux.
View Article and Find Full Text PDFWe compared focused and unfocused ultrasound-targeted microbubble destruction (UTMD) for delivery of reporter plasmids to the liver and heart in mice. Optimal hepatic expression was seen with double-depth targeting at 5 and 13 mm in vivo, incorporating a low pulse repetition frequency and short pulse duration. Reporter expression was similar, but the transfection patterns were distinct, with intense foci of transfection using focused UTMD (F-UTMD).
View Article and Find Full Text PDFMicroRNAs (miRNAs) are powerful regulators of protein expression. Many play important roles in cardiac development and disease. While several miRNAs and targets have been well characterized, the abundance of miRNAs and the numerous potential targets for each suggest that the vast majority of these interactions have yet to be described.
View Article and Find Full Text PDFKawasaki disease (KD) is the leading cause of acquired pediatric heart disease in the developed world as 25-30% of untreated patients and at least 5% of treated patients will develop irreversible coronary artery lesions (CAL). Pentraxin-3 (PTX-3) has been well-studied in inflammatory diseases, particularly in cardiovascular diseases associated with vascular endothelial dysfunction. We hypothesized that PTX-3 plays an important role in the development of KD-associated CAL and investigated the circulating levels of PTX-3 in the serum of KD patients.
View Article and Find Full Text PDFBackground: We examined how expanding electrocardiographic trait genome-wide association studies to include ancestrally diverse populations, prioritize more precise phenotypic measures, and evaluate evidence for shared genetic effects enabled the detection and characterization of loci.
Methods: We decomposed 10 seconds, 12-lead electrocardiograms from 34 668 multi-ethnic participants (15% Black; 30% Hispanic/Latino) into 6 contiguous, physiologically distinct (P wave, PR segment, QRS interval, ST segment, T wave, and TP segment) and 2 composite, conventional (PR interval and QT interval) interval scale traits and conducted multivariable-adjusted, trait-specific univariate genome-wide association studies using 1000-G imputed single-nucleotide polymorphisms. Evidence of shared genetic effects was evaluated by aggregating meta-analyzed univariate results across the 6 continuous electrocardiographic traits using the combined phenotype adaptive sum of powered scores test.
In this study, we created a mouse model of methamphetamine cardiomyopathy that reproduces the chronic, progressive dosing commonly encountered in addicted subjects. We gradually increased the quantity of methamphetamine given to C57Bl/6 mice from 5 to 40 mg/kg over 2 or 5 months during two study periods. At the fifth month, heart weight was increased, echocardiograms showed a dilated cardiomyopathy and survival was lower in males, with less effect in females.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
March 2019
The principal regulator of cellular response to low oxygen is hypoxia-inducible factor (HIF)-1, which is stabilized in several forms of heart failure. Our laboratory developed a mouse strain in which a stable form of HIF-1 can be inducibly expressed in cardiomyocytes. Strikingly, these mice show a rapid decrease in cardiac contractility and a rapid loss of SERCA2 protein, which is also seen in heart failure.
View Article and Find Full Text PDFBackground: It has been reported that women have higher 30-day readmission rates than men after acute coronary syndrome (ACS). However, readmission after percutaneous coronary intervention (PCI) for ACS is a distinct subset of patients in whom gender differences have not been adequately studied.
Methods: Hawaii statewide hospitalization data from 2010 to 2015 were assessed to compare gender differences in 30-day readmission rates among patients hospitalized with ACS who underwent PCI during the index hospitalization.
Aims: Hypoxia-inducible factor-1 alpha (HIF-1α) is a key transcription factor responsible for the induction of genes that facilitate adaptation to hypoxia. To study HIF-1 signalling in the heart, we developed a mouse model in which an oxygen-stable form of HIF-1α can be inducibly expressed in cardiac myocytes, under the regulation of tetracycline.
Methods And Results: Remarkably, expression of the transgene in mice generated two distinct phenotypes.
Alternative splicing of RNA is an underexplored area of transcriptional response. We expect that early changes in alternatively spliced genes may be important for responses to cardiac injury. Hypoxia inducible factor 1 (HIF1) is a key transcription factor that rapidly responds to loss of oxygen through alteration of metabolism and angiogenesis.
View Article and Find Full Text PDFBackground: Kawasaki disease (KD) is the most common acquired heart disease in children of the developed world, and triggers progressive coronary artery lesions (CAL) in 30% of cases if left untreated. Despite standard anti-inflammatory treatment for KD, CAL (dilation or aneurysm) still occurs in 5-10% of children, increasing their risk for fatal coronary artery complications. CAL is mediated by enhanced matrix metalloproteinase activity and elastin breakdown induced by the inflammatory process in the coronary artery wall.
View Article and Find Full Text PDFBackground: Unicuspid aortic valve (UAV) is a rare disorder, often difficult to distinguish from bicuspid aortic valve (BAV). BAV and UAV share valve pathology such as the presence of a raphe, leaflet fusion, aortic stenosis, aortic regurgitation, and/or ascending aortic dilatation, but a comprehensive echocardiographic comparison of patients with UAV and BAV has not been previously performed.
Methods: We investigated UAV and BAV patients at an early stage of disease included in GenTAC, a national registry of genetically related aortic aneurysms and associated cardiac conditions.
This study analyzed the impact of sex, hemodynamic profile, and valve fusion pattern on aortopathy associated with bicuspid aortic valve (BAV). The National Heart Lung and Blood Institute-sponsored National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC) provided comprehensive information on a large population of well-characterized patients with BAV. Of 969 enrolled patients with BAV, 551 (57%, 77% male) had already undergone valvular and/or aortic surgery.
View Article and Find Full Text PDFBackground: The associations of age and sex with phenotypic features of Marfan syndrome have not been systematically examined in a large cohort of both children and adults.
Methods And Results: We evaluated 789 Marfan patients enrolled in the National Heart, Lung, and Blood Institute GenTAC (Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions) Registry (53% male; mean age 31 [range: 1-86 years]). Females aged ≥15 and males aged ≥16 years were considered adults based on average age of skeletal maturity.
Hawaii J Med Public Health
April 2017
Statins are lipid-lowering medications used for primary and secondary prevention of atherosclerotic disease and represent a substantial portion of drug costs in the United States. A better understanding of prescribing patterns and drug costs should lead to more rational utilization and help constrain health care expenditures in the United States. The 2013 Medicare Provider Utilization and Payment Data: Part D Prescriber Public Use File for the State of Hawai'i was analyzed.
View Article and Find Full Text PDFHeart Rhythm
April 2017
The electrocardiographic QRS duration, a measure of ventricular depolarization and conduction, is associated with cardiovascular mortality. While single nucleotide polymorphisms (SNPs) associated with QRS duration have been identified at 22 loci in populations of European descent, the genetic architecture of QRS duration in non-European populations is largely unknown. We therefore performed a genome-wide association study (GWAS) meta-analysis of QRS duration in 13,031 African Americans from ten cohorts and a transethnic GWAS meta-analysis with additional results from populations of European descent.
View Article and Find Full Text PDFBackground: The risk of aortic complications associated with pregnancy in women with Marfan syndrome (MFS) is not fully understood.
Methods And Results: MFS women participating in the large National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC) were evaluated. Among 184 women with MFS in whom pregnancy information was available, 94 (51%) had a total of 227 pregnancies.