Adverse birth outcomes are common in HIV-positive pregnant women receiving combination antiretroviral therapy (cART), especially when cART is initiated in early pregnancy. The mechanisms remain poorly understood. Using a mouse model we demonstrate that protease inhibitor based-cART exposure beginning on day 1 of pregnancy was associated with a pro-angiogenic/pro-branching shift in the placenta driven by lower Flt-1 levels and higher Gcm-1 expression. Micro-CT imaging revealed an increase in the number of arterioles in cART-treated placentas, which correlated with fetal growth restriction. Delaying initiation of cART, or supplementing cART-treated mice with progesterone, prevented the pro-angiogenic/pro-branching shift and the associated placenta vascular changes. In agreement with our mouse findings, we observed an increase in the number of terminal-villi capillaries in placentas from HIV-positive cART-exposed women compared to HIV-negative controls. Capillary number was inversely correlated to maternal progesterone levels. Our study provides evidence that cART exposure during pregnancy influences placenta vascular formation that may in turn contribute to fetal growth restriction. Our findings highlight the need for closer investigation of the placenta in HIV-positive pregnancies, particularly for pregnancies exposed to cART from conception, and suggest that progesterone supplementation could be investigated as a possible intervention to improve placenta function in HIV-positive pregnant women.

A therosclerosis is the main underlying pathology of cardiovascular disease, which accounts for the majority of deaths in developed nations.1 Myeloid lineage cells are critical mediators in the development of atherosclerosis and account for the majority of a lesion's cellular bulk.2 Within the atherosclerotic lesion, macrophages phagocytose modified lipid particles becoming lipid engorged foam cells. Foam cells exacerbate disease progression through the secretion of proinflammatory cytokines and growth factors. In advanced lesions, foam cells undergo apoptosis leading to the formation of a lipid-rich, acellular, and highly thrombotic necrotic core. The underlying molecular mechanisms that regulate myeloid cell behavior during atherosclerosis remain poorly defined.Increasing evidence suggests that myeloid cell subpopulations are heterogeneous and have distinctive phenotypes that play unique roles in disease states. Macrophages are often broadly classified as having a classical (M1) or an alternative (M2) phenotype. M1 macrophages, elicited by toll-like receptor or interferon-γ receptor stimulation, are the most prominent macrophages at sites of inflammation and exacerbate the inflammatory response through the secretion of proinflammatory cytokines and chemoatractants.3,4 M1 macrophages promote atherosclerotic lesion development and complexity.5-7 M2 macrophages patrol tissue, perform reparative and immunoregulatory functions, efferocytose debris, and are antiatherogenic. 3,4,8 Other macrophage subtypes have been identified in atherosclerotic lesions, including M4, Mox, and Mhem; however, their roles are less well characterized. 3,5,9,10 Our understanding of the cellular signaling networks that regulate macrophage polarization in the context of atherosclerosis and the relative contribution of each phenotype to the progression and development of atherosclerosis is limited.Glycogen synthase kinase (GSK)-3 α and β are homologous serine/threonine kinases encoded by separate genes. 11GSK3α and GSK3β share 98% amino acid homology within their kinase domain but only 36% homology in the C-terminal domain. GSK3α (51 kDa) is 5 kDa larger than GSK3β (46 kDa) because of an N-terminal glycine-rich domain with an © 2015 American Heart Association, Inc. Objective-Glycogen synthase kinase (GSK)-3α/β has been implicated in the pathogenesis of diabetes mellitus, cancer, Alzheimer, and atherosclerosis. The tissue-and homolog-specific functions of GSK3α and β in atherosclerosis are unknown. This study examines the effect of hepatocyte or myeloid cell deletion of GSK3α or GSK3β on atherosclerosis in low-density lipoprotein receptor (LDLR) −/− mice. Approach and Results-We ablated GSK3α or GSK3β expression in hepatic or myeloid cells of LDLR −/− mice, and mice were fed a high-fat diet for 10 weeks. GSK3α or GSK3β deficiency in hepatic or myeloid cells did not affect metabolic parameters, including plasma lipid levels. Hepatic deletion of GSK3α or GSK3β did not affect the development of atherosclerosis or hepatic lipid content. Myeloid ...

Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have been developed to facilitate the study of the molecular and cellular pathophysiology of this disease. In this manuscript we describe specific techniques for the quantification and characterization of atherosclerotic lesions in the murine aortic sinus and ascending aorta. The advantage of this procedure is that it provides an accurate measurement of the cross-sectional area and total volume of the lesion, which can be used to compare atherosclerotic progression across different treatment groups. This is possible through the use of the valve leaflets as an anatomical landmark, together with careful adjustment of the sectioning angle. We also describe basic staining methods that can be used to begin to characterize atherosclerotic progression. These can be further modified to investigate antigens of specific interest to the researcher. The described techniques are generally applicable to a wide variety of existing and newly created dietary and genetically-induced models of atherogenesis. Video LinkThe video component of this article can be found at