Recombinant Interleukin-19 Suppresses the Formation and Progression of Experimental Abdominal Aortic Aneurysms.

Background Interleukin-19 is an immunosuppressive cytokine produced by immune and nonimmune cells, but its role in abdominal aortic aneurysm (AAA) pathogenesis is not known. This study aimed to investigate interleukin-19 expression in, and influences on, the formation and progression of experimental AAAs. Methods and Results Human specimens were obtained at aneurysm repair surgery or from transplant donors. Experimental AAAs were created in 10- to 12-week-old male mice via intra-aortic elastase infusion. Influence and potential mechanisms of interleukin-19 treatment on AAAs were assessed via ultrasonography, histopathology, flow cytometry, and gene expression profiling. Immunohistochemistry revealed augmented interleukin-19 expression in both human and experimental AAAs. In mice, interleukin-19 treatment before AAA initiation via elastase infusion suppressed aneurysm formation and progression, with attenuation of medial elastin degradation, smooth-muscle depletion, leukocyte infiltration, neoangiogenesis, and matrix metalloproteinase 2 and 9 expression. Initiation of interleukin-19 treatment after AAA creation limited further aneurysmal degeneration. In additional experiments, interleukin-19 treatment inhibited murine macrophage recruitment following intraperitoneal thioglycolate injection. In classically or alternatively activated macrophages in vitro, interleukin-19 downregulated mRNA expression of inducible nitric oxide synthase, chemokine C-C motif ligand 2, and metalloproteinases 2 and 9 without apparent effect on cytokine-expressing helper or cytotoxic T-cell differentiation, nor regulatory T cellularity, in the aneurysmal aorta or spleen of interleukin-19-treated mice. Interleukin-19 also suppressed AAAs created via angiotensin II infusion in hyperlipidemic mice. Conclusions Based on human evidence and experimental modeling observations, interleukin-19 may influence the development and progression of AAAs.

Production of a High-affinity Monoclonal Antibody Reactive with Folate Receptors Alpha and Beta.

Folate receptors α (FRα) and ß (FRß) are two isoforms of the cell surface glycoprotein that binds folate. The expression of FRα is rare in normal cells and elevated in cancer cells. Thus, FRα-based tumor-targeted therapy has been a focus area of laboratory research and clinical trials. Recently, it was shown that a significant fraction of tumor-associated macrophages expresses FRß and that these cells can enhance tumor growth. Although FRα and FRß share 70% identity in their deduced amino acid sequence, a monoclonal antibody (MAb) reactive with both receptors has not been developed. A MAb that can target both FRα-expressing cancer cells and FRß-expressing tumor-associated macrophages may provide a more potent therapeutic tool for cancer than individual anti-FRα or anti-FRß MAbs. In this study, we developed a MAb that recognizes both FRα and FRß (anti-FRαß). The anti-FRαß specifically stained trophoblasts and macrophages from human placenta, synovial macrophages from rheumatoid arthritis patient, liver macrophages from cynomolgus monkey and common marmoset, and cancer cells and tumor-associated macrophages from ovary and lung carcinomas. Surface plasmon resonance showed that the anti-FRαß bound to soluble forms of the FRα and FRß proteins with high affinity (KD=6.26×10(-9) M and 4.33×10(-9) M, respectively). In vitro functional analysis of the anti-FRαß showed that this MAb mediates complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, and antibody-dependent cellular phagocytosis of FRα-expressing and FRß-expressing cell lines. The anti-FRαß MAb is a promising therapeutic candidate for cancers in which macrophages promote tumor progression.

Novel Therapy for Atherosclerosis Using Recombinant Immunotoxin Against Folate Receptor ß-Expressing Macrophages.

BACKGROUND: Folate receptor ß (FRß) is induced during macrophage activation. A recombinant immunotoxin consisting of the truncated Pseudomonas exotoxin A (PE38) conjugated to an anti-FRß antibody (anti-FRß-PE38) has been reported to kill activated macrophages in inflammatory diseases. To elucidate the effect of an immunotoxin targeting FRß on atherosclerosis, we determined the presence of FRß-expressing macrophages in atherosclerotic lesions and administered the FRß immunotoxin in apolipoprotein E-deficient mice. METHODS AND RESULTS: The FRß-expressing macrophages were observed in atherosclerotic lesions of apolipoprotein E-deficient mice. At 15 or 35 weeks of age, the apolipoprotein E-deficient mice were divided into 3 groups and were intravenously administered 0.1 mg/kg of anti-FRß-PE38 (immunotoxin group), 0.1 mg/kg of PE38 (toxin group), or 0.1 mL of saline (control group) every 3 days, for a total of 5 times for each age group. The mice were analyzed at 21 or 41 weeks of age. Treatment with the immunotoxin resulted in 31% and 22% reductions in atherosclerotic lesions of the 21- and 41-week-old mice, respectively (P<0.05). Administration of immunotoxin reduced the numbers of FRß- and tumor necrosis factor-α-expressing macrophages, reduced cell proliferation, and increased the number of apoptotic cells (P<0.05). Real-time polymerase chain reaction demonstrated that the expression of FRß and tumor necrosis factor-α mRNA was significantly decreased in the immunotoxin group (P<0.05). CONCLUSIONS: These results suggest that FRß-expressing macrophages exist in the atherosclerotic lesions of apolipoprotein E-deficient mice and that FRß immunotoxin administration reduces the progression of atherosclerotic lesions in younger and older individuals. The recombinant FRß immunotoxin targeting activated macrophages could provide a novel therapeutic tool for atherosclerosis. (J Am Heart Assoc. 2012;1:e003079 doi: 10.1161/JAHA.112.003079.).

Waon therapy upregulates Hsp90 and leads to angiogenesis through the Akt-endothelial nitric oxide synthase pathway in mouse hindlimb ischemia.

BACKGROUND: Thermal therapy, namely Waon therapy, has previously been reported to regulate nitric oxide (NO) and endothelial NO synthase (eNOS) and augment ischemia-induced angiogenesis in mice and improve limb ischemia in patients with peripheral artery disease. The aim of this study was to clarify the precise mechanism by which Waon therapy augments angiogenesis in mice with hindlimb ischemia. METHODS AND RESULTS: Unilateral hindlimb ischemia was induced in apolipoprotein E-deficient mice and Waon therapy was performed for 5 weeks. Heat shock protein 90 (Hsp90), phosphorylated-Akt, and phosphorylated-eNOS were detected in arterial endothelial cells of ischemic hindlimbs and all were upregulated by Waon therapy compared to controls. Waon therapy also increased serum concentrations of nitrite and nitrate. Capillary density and the ischemic limb/normal side blood perfusion ratio monitored by laser Doppler perfusion imaging in the Waon therapy group were significantly increased beyond those in the control group. The effect of Waon therapy on angiogenesis through the activation of the Hsp90/Akt/eNOS pathway was attenuated by the administration of a Hsp90 inhibitor. CONCLUSIONS: It is suggested that Waon therapy upregulates Hsp90, which contributes to the activation of the Akt/eNOS/NO pathway, and induces angiogenesis in mice with hindlimb ischemia.

Effects of valsartan on fibrinolysis in hypertensive patients with metabolic syndrome.

BACKGROUND: The purpose of this study was to analyze the effect of valsartan on abnormal adipocyte metabolism and prothrombotic state in hypertensive patients with metabolic syndrome (MetS). METHODS AND RESULTS: We conducted a multicenter, prospective, randomized, parallel-group controlled trial in 150 hypertensive patients with MetS. They were randomly assigned to receive either 80-160 mg valsartan per day (valsartan group, n=79) or other conventional treatment without a renin-angiotensin system (RAS) inhibitor (non-RAS inhibitor group, n=71). After 1 year, there were no significant differences between the 2 groups in the changes in systolic and diastolic blood pressures (valsartan: 153±15/86±15 to 138±16/77±12 mmHg; non-RAS inhibitor: 150±14/82±15 to 137±15/76±10 mmHg). There was a significant difference in the change in the levels of plasminogen activator inhibitor-1 (PAI-1) between the 2 groups after 1 year (valsartan: 3.7±3.2 ng/ml; non-RAS inhibitor: 5.8±3.3 ng/ml, P=0.04). There was no significant difference between groups in the change in the concentration of adiponectin after 1 year (valsartan: 0.3±0.4 µg/ml; non-RAS inhibitor: 0.9±0.4 µg/ml, P=0.22). The animal study showed aortic PAI-1 protein expression was reduced in double knockout mice of angiotensin II type 1a receptor and apolipoprotein E (apoE) compared with the apoE knockout mice. CONCLUSIONS: Valsartan reduced plasma PAI-1 levels compared to non-RAS inhibitor in hypertensive patients with MetS, which suggests it may be useful for improving fibrinolytic function.

Comparative study of therapeutic effects of short- and long-acting loop diuretics in outpatients with chronic heart failure (COLD-CHF).

BACKGROUND: Loop diuretics have two different classes with different duration of activity: short-acting such as furosemide (duration of activity, 6h) and long-acting such as azosemide (duration of activity, 10-12h). We conducted a multicenter, randomized, controlled trial in order to compare the therapeutic effects of azosemide, a long-acting loop diuretic, and furosemide, a short-acting one, on neurohumoral factors and cardiac function in outpatients with chronic heart failure (CHF). METHODS: We enrolled 98 patients with CHF who were receiving furosemide and an angiotensin-converting enzyme inhibitor, and they were randomly divided into furosemide (n=49) and azosemide (n=49) groups. The furosemide group continued furosemide at the same dosage, and the azosemide group switched from furosemide to azosemide. At baseline and after 3 months, we measured body weight, and levels of brain natriuretic peptide (BNP), atrial natriuretic peptide (ANP), norepinephrine, active renin, creatinine, blood urea nitrogen, sodium, potassium, and hematocrit. Chest X-ray and echocardiography were also performed. RESULTS: Body weight and plasma levels of BNP and ANP significantly decreased after 3 months in the azosemide group compared to the furosemide group. There were no significant differences in changes of levels of creatinine, blood urea nitrogen, sodium, potassium, hematocrit, norepinephrine, and active renin after 3 months between the furosemide and azosemide groups. Echocardiography and chest X-ray did not demonstrate significant differences between the two groups. CONCLUSIONS: Long-acting azosemide is suggested to be useful for the improvement of neurohumoral factors compared with short-acting furosemide in patients with CHF.

Loss of clusterin limits atherosclerosis in apolipoprotein E-deficient mice via reduced expression of Egr-1 and TNF-α.

AIM: Whether clusterin/apolipoprotein J is antiatherogenic or proatherogenic is controversial. We reported that clusterin was markedly induced in media and neointima after vascular injury and that reduced clusterin expression reduced the proliferation of vascular smooth muscle cells (VSMCs), which induced G1 arrest via p53 and p21. The purpose of this study was to investigate the physiological function of clusterin in atherosclerosis using double-knockout mice (D-KO) of apolipoprotein E-deficient mice (apoE-KO) and clusterin-deficient mice (CLU-KO). METHODS AND RESULTS: Atherosclerotic lesions in the aortic root were quantitated at 20 weeks of age. Atherosclerotic lesions of D-KO were significantly smaller than those of apoE-KO (D-KO: 0.176±0.078 mm(2) vs. apoE-KO: 0.365±0.164 mm(2), p< 0.001). To identify underlying atherosclerotic mechanisms that were blocked by loss of clusterin, we performed immunohistochemical analysis of Egr-1. Egr-1 immunoreactivity in the nuclei of VSMCs in atherosclerotic lesions of apoE-KO was upregulated, whereas it was not in D-KO lesions. Western blotting demonstrated that the expression levels of Egr-1 and TNF-α in the D-KO were significantly lower than those in the apoE-KO. When VSMCs and macrophages were obtained from D-KO and apoE-KO, Western blotting showed that the expression levels of Egr-1 and TNF-α in VSMCs and macrophages of D-KO were significantly lower than those of apoE-KO. CONCLUSION: Loss of clusterin strongly suppressed apoE-KO-induced atherosclerotic lesions at a step prior to the expression of Egr-1 and TNF-α, suggesting that clusterin is a candidate for an antiatherogenic target.

Deficiency of clusterin inhibits neointimal hyperplasia after vascular injury.

AIM: Increased clusterin mRNA and protein levels have been detected in various tissues undergoing stress, and we previously reported that clusterin is markedly induced in media and neointima following vascular injury. The present study therefore investigated the impact of clusterin on neointimal hyperplasia following vascular injury. METHODS AND RESULTS: As compared with wild-type mice, clusterin knockout mice (clusterin-KO) demonstrated a significant decrease of the intima/media ratio 4 weeks after cuff placement. Immunohistochemical analysis of injured femoral arteries in clusterin-KO demonstrated the accumulation of p53 in nuclei of neointimal vascular smooth muscle cells (VSMCs). Moreover, VSMCs from either clusterin-KO or rat VSMCs treated with clusterin-short-interfering (si) RNA subjected to static stretch exhibited significantly increased p53 and p21, and increased G1 cell cycle arrest as indicated by flow cytometry compared with VSMCs from wild-type mice. CONCLUSION: Reduced clusterin expression reduced the proliferation of VSMCs and induced G1 arrest via p53 and p21. Clusterin therefore represents a promising molecular target to limit restenosis after coronary intervention.