Wednesday, December 7, 2022
12/7/2022
PROJECT SUMMARY Exposure to early life stress (ELS) often is accompanied by adverse health outcomes earlier in adulthood and with more severity such as in the case of Systemic Lupus Erythamateous (SLE), an autoimmune disease. The risk for autoimmunity and cardiovascular disease (CVD) increases with ELS exposure and CVD is the predominant cause for early mortality in SLE patients. This project addresses the gap in knowledge of why coexistence with ELS is associated with higher prevalence and heart disease in SLE. In the case of SLE— despite reports linking worsened disease activity in patients with ELS—there have been no studies in preclinical rodent models of SLE in conjunction with ELS. Several investigations demonstrate that ELS is associated with a pro-inflammatory phenotype and vascular dysfunction. In our mouse model of ELS, maternal separation with early weaning (MSEW), we observed aortic endothelial dysfunction dependent on superoxide and increased numbers of F4/80+ macrophages, an innate immune cell, in the adventitia of the aorta. In addition, vessel dysfunction and aortic stiffness is exaggerated in MSEW mice subjected to pristane induction of SLE. We expect impairment in vascular function is due to proinflammatory macrophage presence in MSEW animals. Preliminary data shows mitochondrial dysfunction is present in MSEW mice indicating the superoxide impacting endothelial dysfunction may be mitochondrial derived. Thus, our overall hypothesis states that ELS accentuates the development and severity of aortic disease in a mouse model of SLE through mitochondrial-derived superoxide production and activated pro-inflammatory macrophages. This project is designed with two specific aims. First, we will determine if macrophages mediate development of aortic disease in ELS. We will use flow cytometry and RNA sequencing to determine immune activation differences between MSEW and control mice. We then will determine if absence of macrophages in vivo prevents MSEW vascular dysfunction compared to controls. Second, studies will address if ELS mediates enhanced development of aortic disease in SLE through mitochondrial superoxide production. The pristane-induced model of SLE will be used in conjunction with the MSEW protocol to determine if oxidative stress, previously linked to SLE-mediated hypertension, is accelerated by ELS. Experiments will examine markers for CVD in SLE using telemetry and vascular reactivity after ELS. We will also measure CVD and disease after blocking mitochondrial superoxide by MitoTEMPOL. We expect to see (i)elevated inflammatory macrophages that, when absent, reduce vascular dysfunction and (ii)a greater CVD burden in MSEW SLE mice reduced by MitoTEMPOL treatment. This project is critical to begin to understand the mechanistic relationship of ELS in SLE as well as crucial for studying immune driven diseases with CVD complications. ELS is associated with adverse health outcomes in a variety of diseases. Advances in the ELS field are essential to developing relevant and accessible intervention and prevention strategies for patients. Our studies provide two potentially complementary pathways for ELS-driven CVD.
HHS’ Tracking Accountability in Government Grants System (TAGGS) website provides access to detailed descriptions of grants, loans, aggregated direct payments and other types of financial assistance awarded by the HHS Operating Divisions (OPDIVs) and the Office of the Secretary Staff Divisions (STAFFDIVs).
