In Vivo Magnetic Resonance Imaging-Based Detection of Heterogeneous Endothelial Response in Thoracic and Abdominal Aorta to Short-Term High-Fat Diet Ascribed to Differences in Perivascular Adipose Tissue in Mice
JOURNAL OF THE AMERICAN HEART ASSOCIATION
Authors: Bar, Anna; Kieronska-Rudek, Anna; Proniewski, Bartosz; Suraj-Prazmowska, Joanna; Czamara, Krzysztof; Marczyk, Brygida; Matyjaszczyk-Gwarda, Karolina; Jasztal, Agnieszka; Kus, Edyta; Majka, Zuzanna; Kaczor, Agnieszka; Kurpinska, Anna; Walczak, Maria; Pieterman, Elsbet J.; Princen, Hans M. G.; Chlopicki, Stefan
Abstract
Background Long-term feeding with a high-fat diet (HFD) induces endothelial dysfunction in mice, but early HFD-induced effects on endothelium have not been well characterized. Methods and Results Using an magnetic resonance imaging-based methodology that allows characterization of endothelial function in vivo, we demonstrated that short-term (2 weeks) feeding with a HFD to C57BL/6 mice or to E3L.CETP mice resulted in the impairment of acetylcholine-induced response in the abdominal aorta (AA), whereas, in the thoracic aorta (TA), the acetylcholine-induced response was largely preserved. Similarly, HFD resulted in arterial stiffness in the AA, but not in the TA. The difference in HFD-induced response was ascribed to distinct characteristics of perivascular adipose tissue in the TA and AA, related to brown- and white-like adipose tissue, respectively, as assessed by histology, immunohistochemistry, and Raman spectroscopy. In contrast, short-term HFD-induced endothelial dysfunction could not be linked to systemic insulin resistance, changes in plasma concentration of nitrite, or concentration of biomarkers of glycocalyx disruption (syndecan-1 and endocan), endothelial inflammation (soluble form of vascular cell adhesion molecule 1, soluble form of intercellular adhesion molecule 1 and soluble form of E-selectin), endothelial permeability (soluble form of fms-like tyrosine kinase 1 and angiopoietin 2), and hemostasis (tissue plasminogen activator and plasminogen activator inhibitor 1). Conclusions Short-term feeding with a HFD induces endothelial dysfunction in the AA but not in the TA, which could be ascribed to a differential response of perivascular adipose tissue to a HFD in the AA versus TA. Importantly, early endothelial dysfunction in the AA is not linked to elevation of classical systemic biomarkers of endothelial dysfunction.
The Presence of Survivin on B Cells from Myasthenia Gravis Patients and the Potential of an Antibody to a Modified Survivin Peptide to Alleviate Weakness in an Animal Model
JOURNAL OF IMMUNOLOGY
Authors: Zhang, Xiangyang; Ciesielski, Michael; Fenstermaker, Robert A.; Kaminski, Henry J.; Kusner, Linda L.
Abstract
Myasthenia gravis (MG) is an autoimmune disease in which Abs target neuromuscular junction proteins, in particular the acetylcholine receptor. We previously identified the antiapoptotic protein survivin in the autoreactive B cells and plasma cells of MG patients. To further define the role of survivin in MG, we have assessed PBMCs from 29 patients with MG and 15 controls. We confirmed the increased expression of survivin in CD20(+) lymphocytes from MG patients compared with controls. Furthermore, the CD20(+) population of cells from MG patients contained a higher percentage of extracellular survivin compared with controls. The analysis of CD4(+) cells showed an increased percentage of intracellular survivin in MG patients compared with controls, whereas the extracellular survivin CD4(+) percentage was unaffected. In an experimental mouse model of MG, we assessed the therapeutic potential of an Ab raised to a modified survivin peptide but cross-reactive to survivin. Ab treatment reduced disease severity, lowered acetylcholine receptor-specific Abs, and decreased CD19(+) survivin(+) splenocytes. The ability to target survivin through Ab recognition of autoreactive cells offers the potential for a highly specific therapeutic agent for MG.