Introduction: Nonclinical evaluation of the cardiovascular effects of novel chemical or biological entities (NCE, NBEs) is crucial for supporting first-in-human clinical trials. One important aspect of these evaluations is the assessment of potential QT/QTc prolongation risk, as drug-induced QT prolongation can have catastrophic effects. The recent publication of E14/S7B Q&As allows for the situational incorporation of nonclinical QTc data as part of an integrated risk assessment for a Thorough QT (TQT) waiver application provided certain best practice criteria are met.
View Article and Find Full Text PDFThe pathogenesis of coronary lesion development is a multi-factorial process involving a number of different cell types and covariates, and injury and dysfunction of the vascular endothelium is an important marker and likely participant in the initiation and/or progression of most forms of heart disease. In addition to chronic dysfunction of endothelial responses in patients with established heart disease, there is evidence that 'acute insults' can cause measurable dysfunction in vascular response in humans (drug toxicities, hypoxia, high fat meal). Such repeated acute insults may contribute to disease risk in otherwise healthy individuals or promote disease progression in established patients.
View Article and Find Full Text PDFCardiovascular disease is an important complication of human immunodeficiency virus/acquired immune deficiency syndrome (AIDS), but the mechanism(s) involved are poorly understood. Although co-infecting pathogens have been implicated as an important factor in AIDS progression, no studies have investigated these interactions in cardiac tissue. We recently demonstrated that the murine AIDS model (LPBM5 retroviral infection) mimics human immunodeficiency virus-related cardiac dysfunction and pathology.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
October 2005
Increased life expectancy of human immunodeficiency virus (HIV)-positive patients has led to evidence of complications apparently not directly related to immunodeficiency or opportunistic infection, including increased cardiovascular risk. We tested the hypothesis that vascular dysfunction occurs in the murine acquired immune deficiency syndrome (AIDS) model and evaluated potential mechanisms in murine AIDS tissues and relevant human HIV/AIDS vascular tissues. We also investigated endothelial activation and/or endothelial protein nitration and their association with time-dependent vascular dysfunction.
View Article and Find Full Text PDFRecent advances in antiretroviral therapies have enhanced survival of HIV/AIDS patients, but cardiovascular complications have emerged as important issues in this growing patient population. Although the antiviral drug therapies apparently yield cardiac and/or vascular toxicities themselves, several other factors associated with HIV pathogenesis have also been implicated. This brief review provides an overview of the significance and complexities of HIV/ AIDS-related cardiovascular complications and addresses some important mechanistic aspects that may contribute to this important clinical problem.
View Article and Find Full Text PDFHIV-protease inhibitor (HIV-PI) drugs are critical for highly active antiretroviral therapy (HAART) efficacy, but several recent reports have suggested that metabolic and/or cardiovascular toxicities are associated with these drugs. Given the importance of the HIV-PI drug class and the widespread and chronic use of these agents in an expanding patient population, further understanding of this potential drug toxicity is imperative. Here, we investigated a role for direct endothelial toxicity induced by saquinavir (SAQ), the first HIV-PI drug marketed in the United States and still an important component of HAART therapies.
View Article and Find Full Text PDFObjective: Cardiomyopathy and other vascular complications are now recognized as significant components of HIV/AIDS pathogenesis. Although the mechanisms involved in cardiomyopathy are poorly defined, a role for direct retroviral action and/or focal infiltration of activated immune cells have been postulated. Here we investigated mechanisms in retrovirus associated cardiomyopathy using a well-defined mouse model of acquired immunodeficiency.
View Article and Find Full Text PDFMurine models offer potential insights regarding human cardiac disease, but efficient and reliable methods for phenotype evaluation are necessary. We employed non-invasive electrocardiography (ECG) in mice, investigating statistical reliability of these parameters with respect to anesthetic and animal age. Mice (C57BL/6, 8 or 48 weeks) were anesthetized by ketamine/xylazine (K/X, 80/10 mg/kg ip) or by inhalation anesthetic (halothane, HAL; sevoflurane, SEV) and 6 lead ECGs were recorded.
View Article and Find Full Text PDF