BACKGROUND: Epstein-Barr (EB) virus infection stimulates the production of vascular endothelial growth factor (VEGF), which contributes to the progression of angiogenesis. Angiogenesis plays an important role in the development of atherosclerosis. Since serum anti-early antigen EB virus IgG (EBV EA-IgG) titer is a sign of active EB virus infection, EBV EA-IgG titer could be associated with atherosclerosis. The number of minor (T) alleles in VEGF polymorphism rs3025039 has been reported to be inversely associated with serum VEGF concentration, suggesting that rs3025039 might have a strong influence on the association between EBV EA-IgG titer and atherosclerosis. By focusing on the role of VEGF in the development of atherosclerosis, this study aimed to investigate the association between active EB virus infection and atherosclerosis. METHODS: A cross-sectional study of 2,661 older Japanese individuals aged 60-89 years who participated in annual health check-ups during 2017-2019 was conducted. Logistic regression was used to evaluate the association between EBV EA-IgG titer and atherosclerosis in relation to rs3025039 genotype. The influence of rs3025039 (T) allele carrier status on the association between EBV EA-IgG titer and atherosclerosis was also evaluated by using logistic regression. RESULTS: Among rs3025039 CC-homozygotes, with the lowest EBV EA-IgG titer tertile as the reference, the multivariable odds ratio (95% confidence interval) was 1.11 (0.82, 1.50) for the medium tertile and 1.07 (0.78, 1.47) for the high tertile. Among rs3025039 (T) allele carriers, the corresponding values were 1.44 (0.88, 2.36) and 1.88 (1.15, 3.05), respectively. There was a significant interaction between rs3025039 (T) allele carrier status and the association between EBV EA-IgG titer and atherosclerosis (adjusted p = 0.0497). CONCLUSION EBV EA-IgG titer was significantly positively associated with atherosclerosis only among participants who are genetically less likely to have progressive angiogenesis. An angiogenesis-related genetic factor was revealed as a determinant of the association between EBV EA-IgG titer and atherosclerosis. These findings introduce a novel concept that could explain the association between viral infection and atherosclerosis.
Humans ; Aged ; Male ; Middle Aged ; Female ; Japan/epidemiology* ; Atherosclerosis/virology* ; Aged, 80 and over ; Vascular Endothelial Growth Factor A/genetics* ; Epstein-Barr Virus Infections/virology* ; Polymorphism, Single Nucleotide ; Cross-Sectional Studies ; Herpesvirus 4, Human ; Antigens, Viral/immunology* ; Antibodies, Viral/blood* ; Immunoglobulin G/blood* ; Genotype ; East Asian People

PURPOSE: Apoptosis of vascular endothelial cells is a type of endothelial damage that is associated with the pathogenesis of cardiovascular diseases such as atherosclerosis. Heterotrimeric GTP-binding proteins (G proteins), including the alpha 12 subunit of G protein (Galpha12), have been found to modulate cellular proliferation, differentiation, and apoptosis of numerous cell types. However, the role of Galpha12 in the regulation of apoptosis of vascular cells has not been elucidated. We investigated the role of Galpha12 in serum withdrawal-induced apoptosis of human umbilical vein endothelial cells (HUVECs) and its underlying mechanisms. MATERIALS AND METHODS: HUVECs were transfected with Galpha12 small-interfering RNA (siRNA) to knockdown the endogenous Galpha12 expression and were serum-deprived for 6 h to induce apoptosis. The apoptosis of HUVECs were assessed by Western blotting and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expressions of microRNAs were analyzed by quantitative real-time PCR. RESULTS: Knockdown of Galpha12 with siRNA augmented the serum withdrawal-induced apoptosis of HUVECs and markedly repressed the expression of microRNA-155 (miR-155). Serum withdrawal-induced apoptosis of HUVECs was inhibited by the overexpression of miR-155 and increased significantly due to the inhibition of miR-155. Notably, the elevation of miR-155 expression prevented increased apoptosis of Galpha12-deficient HUVECs. CONCLUSION: From these results, we conclude that Galpha12 protects HUVECs from serum withdrawal-induced apoptosis by retaining miR-155 expression. This suggests that Galpha12 might play a protective role in vascular endothelial cells by regulating the expression of microRNAs.
*Apoptosis ; Atherosclerosis/*blood/genetics/immunology ; Cell Proliferation ; Endothelial Cells/*metabolism ; GTP-Binding Protein alpha Subunits, G12-G13/*genetics ; Gene Expression Profiling ; Gene Expression Regulation ; Human Umbilical Vein Endothelial Cells/cytology ; Humans ; MicroRNAs/*metabolism ; Protective Agents ; *RNA, Small Interfering ; Real-Time Polymerase Chain Reaction ; *Transfection

OBJECTIVETo establish a uremic apolipoprotein E knockout (apoE-/-) mouse model and explore the relationship between accelerated atherosclerosis and Treg/Teff balance.

METHODSUsing apoE-/- mice with C57BL/6J background, uremic apoE-/- mice were created by electrocautery of the right kidney and nephrectomy of the left, and the control apoE-/- mice received a sham-operation. Two weeks after inducing uremia, the renal function of the mice were evaluated to assess the validity of the model. Ten weeks after the operation, blood samples were obtained from the mice to assess the renal function and serum total cholesterol (TCH); the serum concentrations of transforming growth factor-beta(1) (TGF-beta(1)) and interferon-gamma (IFN-gamma) were detected by ELISA, and CD4(+)CD25(+)Foxp3(+)Treg ratio in the spleen was determined by flow cytometry. RT-PCR was used to detect the expression of Foxp3 and IFN-gamma mRNA in the aorta, and oil red O staining used to investigate the relative atherosclerotic area on the frozen sections of the aortic root. The correlation between the renal function parameters and Treg quantity was analyzed.

RESULTSRenal function detection confirmed successful establishment of the uremic apoE-/- mouse model. Ten weeks after the operation, the relative atherosclerotic plaque area in the aortic root plaque increased significantly, the spleen Treg ratio decreased, the serum concentrations of TGF-beta(1) decreased and IFN-gamma and TCH increased, the expression of aortic Foxp3 mRNA decreased and IFN-gamma mRNA increased as compared with those in the control apoE-/- mice. A significant inverse correlation was found between the renal function parameters and Treg quantity in uremic apoE-/- mice.

CONCLUSIONIn uremic apoE-/- mice, accelerated aortic atherosclerosis is correlated to the T cell subset (Treg/Teff) imbalance shown by decreased quantity and impaired function of Treg and enhanced activity of Teff.

Animals ; Aorta ; pathology ; Apolipoproteins E ; genetics ; Atherosclerosis ; complications ; immunology ; pathology ; Cholesterol ; blood ; Disease Progression ; Female ; Forkhead Transcription Factors ; metabolism ; Gene Knockout Techniques ; Interferon-gamma ; blood ; metabolism ; Male ; Mice ; Random Allocation ; T-Lymphocyte Subsets ; immunology ; T-Lymphocytes, Regulatory ; immunology ; Transforming Growth Factor beta1 ; blood ; Uremia ; complications ; genetics ; immunology

It has been hypothesized that blood infusion of reconstituted HDL (rHDL) is a possible therapeutic strategy for the treatment of coronary artery disese. To compare short-term anti-inflammatory activity of wildtype (WT) apoA-I and point mutants, each rHDL containing WT, V156K, or R173C was infused into apo-E deficient atherosclerotic mice. Each rHDL was injected via the tail vein at a dosage of 120 mg/kg of body weight in 0.4 ml of tris-buffered saline (TBS), and blood was then collected at 24 and 48 h post-injection. Although regression activity was observed in each of the rHDL infused groups, a 30% reduction in the lipid-stained area of the aortic sinus was observed in the V156K and R173C-rHDL groups when compared to that of the WT-rHDL group, and this reduction was well correlated with an approximately 60% reduction in the accumulation of macrophages in the lesion area. Additionally, the groups that received the V156K and R173C-rHDL treatments showed smaller increases in the GOT, GPT, interleukin-6, myeloperoxidase (MPO) and lipid hydroperoxide (LPO) serum levels than those that received the WT-rHDL treatment. In addition, the strongest serum paraoxonase and ferric reducing ability was observed in the V156K and R173C-rHDL groups. In vitro nitration and chlorination of apoA-I by MPO treatment revealed that V156K-rHDL and R173C-rHDL were less susceptible to chlorination. Furthermore, rHDL treatment inhibited cellular uptake of oxidized LDL by macrophage cells and the production of proatherogenic species in culture media. In conclusion, blood infusions of the rHDLs exerted in vivo regression activity with anti-inflammatory and antioxidant activity in apo-E deficient mice and THP-1 cells, especially in those that were treated with V156K and R173C apoA-I.
Animals ; Anti-Inflammatory Agents/immunology/*therapeutic use ; Apolipoprotein A-I/blood/genetics/immunology/*therapeutic use ; Apolipoproteins E/genetics ; Aryldialkylphosphatase/blood/metabolism ; Atherosclerosis/*drug therapy ; Cell Line ; Cell Membrane Permeability ; Cholesterol/blood/metabolism ; Humans ; Lipoproteins, HDL/genetics/immunology/*therapeutic use ; Lipoproteins, LDL/metabolism ; Macrophages/cytology ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Oxidation-Reduction/*drug effects ; Peroxidase/blood/metabolism ; Point Mutation