Comparison of Prostate Biopsy with or without Prebiopsy Multiparametric Magnetic Resonance Imaging for Prostate Cancer Detection: An Observational Cohort Study.

PURPOSE: We hypothesized that 1) introducing prebiopsy multiparametric magnetic resonance imaging would increase the diagnostic yield of transrectal prostate biopsy and 2) this would inform recommendations regarding systematic transrectal prostate biopsy in the setting of negative prebiopsy multiparametric magnetic resonance imaging. MATERIALS AND METHODS: A total of 997 biopsy naïve patients underwent transrectal prostate biopsy alone to June 2016 (cohort 1) and thereafter 792 underwent transrectal prostate biopsy following prebiopsy multiparametric magnetic resonance imaging (cohort 2). Patients with lesions on prebiopsy multiparametric magnetic resonance imaging underwent cognitive targeted plus systematic transrectal prostate biopsy. Patients without lesions underwent systematic transrectal prostate biopsy. RESULTS: Cohort 2 comprised younger men (age 68 vs 69 years, p = 0.01) with lower prostate specific antigen (7.6 vs 7.9 ng/ml, p = 0.024) and smaller prostate volume (56.1 vs 62 cc, p = 0.006). In cohort 2 vs cohort 1 there was no increase in overall prostate cancer detection (57.6% vs 56.7%, p = 0.701), the Gleason Grade Group or the number of positive cores (each p >0.05). Increased multifocal prostatic intraepithelial neoplasia, maximum prostate cancer core length (5 mm or greater vs less than 5 mm) and radical surgery/high intensity focused ultrasound (each p <0.05) were observed in cohort 2. For Gleason Grade Group 2-5 prostate cancer negative prebiopsy multiparametric magnetic resonance imaging had 88.1% sensitivity, 59.8% specificity, 67.8% positive predictive value and 84% negative predictive value. For negative prebiopsy multiparametric magnetic resonance images a prostate specific antigen density cutoff of 0.15 ng/ml2 or greater increased clinically significant prostate cancer detection only if the latter was defined as Gleason Grade Group 3-5 disease and/or tumor length 6 mm or greater. CONCLUSIONS: Introducing prebiopsy multiparametric magnetic resonance imaging in our clinical setting increased the diagnostic yield of prostate cancer per biopsy core. Not performing a systematic transrectal prostate biopsy when prebiopsy multiparametric magnetic resonance imaging was negative would have led to under detection of 15.1% of Gleason Grade Group 2 or greater prostate cancer cases (approximately 1 in 6).

Laparoscopic high-intensity focused ultrasound for renal tumours: a proof of concept study.

UNLABELLED: Study Type--Therapy (case series) Level of Evidence What's known on the subject? and What does the study add? Renal cancer is increasingly diagnosed when tumours are small and asymptomatic, during routine abdominal imaging. Whilst surgery is an effective and potentially curative option, it carries a significant risk of complications. Recent work suggests that thermally ablative therapies (RFA, cryotherapy, HIFU) may be suitable minimally invasive treatment options in selected patients. The success of extracorporeal HIFU has been limited by the abdominal wall and rib-cage limiting energy delivery. For this study, a purpose-built laparoscopic HIFU probe was designed to allow direct application of the transducer to the tumour surface, thus facilitating tumour destruction. Successful and accurate tumour destruction was demonstrated, paving the way for further clinical trials, subject to device modifications. OBJECTIVE: • To test and establish clinical proof of concept for a laparoscopic high-intensity focused ultrasound (HIFU) device that facilitates delivery of ultrasound by direct application of a probe to the tumour surface. PATIENTS AND METHODS: • Twelve patients with renal tumours were treated with laparoscopic HIFU using a newly designed probe inserted via an 18-mm laparoscopic port. • HIFU treatment was targeted at a pre-defined proportion of the tumour and immediate laparoscopic partial or radical nephrectomy was then performed. RESULTS: • No tumour ablation was seen in the first five patients which made modifications in the treatment protocol necessary. After this, definite histological evidence of ablation was seen in the remaining seven patients. • The ablated zones were within the targeted area in all patients and no intra-lesional skipping was seen. • Subcapsular skipping was seen at the probe-tumour interface in two patients with viable tumour cells seen at microscopy. • One patient did not undergo surgical extirpation; subsequent biopsy revealed no viable tumour cells. • There were no intraoperative or postoperative complications directly related to HIFU therapy and patients have reached a mean (range) follow-up of 15 (8-24) months with no evidence of metastatic disease or late complications. CONCLUSIONS: • Tumour ablation with laparoscopic HIFU is feasible. • Homogenous ablation can be achieved with no vital tissue within the targeted zone. • The technique is associated with low morbidity and may have a role in the definitive management of small tumours.

Tumour Seeding in the Tract of Percutaneous Renal Tumour Biopsy: A Report on Seven Cases from a UK Tertiary Referral Centre.

The role of percutaneous renal tumour biopsy (RTB) in the management of radiological indeterminate renal masses is long established. Patients with small renal masses who have biopsy-proven renal cell carcinoma (RCC) may be offered surgery, ablative therapy, or active surveillance, and RTB can provide diagnostic tissue from patients with metastatic disease who might benefit from systemic therapy. Current guidelines suggest that tumour seeding along the needle tract is anecdotal, but several cases have been reported recently, although some have been associated with lack of a coaxial sheath. We report on seven patients who underwent surgical resection of RCC in our tertiary referral institution following diagnostic RTB between 2014 and 2017 for whom RTB tract seeding by tumour was identified on histological examination of the resection specimen. One of these patients subsequently developed local tumour recurrence at the site of the previous biopsy.

Novel P2Y12 adenosine diphosphate receptor antagonists for inhibition of platelet aggregation (II): pharmacodynamic and pharmacokinetic characterization.

Antiplatelet drugs are used to prevent aberrant platelet activation in pathophysiologic conditions such as myocardial infarction and ischemic stroke. The key role that ADP plays in this process has led to the development of antiplatelet drugs that target the P2Y12 receptor. The aim of this study was to characterize the pharmacodynamic (PD) and pharmacokinetic (PK) properties of the novel P2Y12 receptor antagonists, BX 667 and BX 048. BX 667 blocks ADP-induced platelet aggregation in human, dog and rat blood (IC50=97, 317 and 3000 nM respectively). BX 667 had nominal effects on collagen-induced aggregation and weakly inhibited arachidonic acid-induced aggregation. BX 667 has an active metabolite, BX 048, that also potently inhibits ADP-induced aggregation (IC50=290 nM) in human blood. BX 667 was shown to have high oral bioavailability in both dog and rat unlike BX 048. Administration of BX 667 resulted in a rapid and sustained inhibition of platelet aggregation where the extent and duration of platelet inhibition was directly proportional to circulating plasma levels. This report describes the PK/PD properties of BX 667 showing that it has the properties required for a potential antiplatelet therapeutic agent.

Novel P2Y12 adenosine diphosphate receptor antagonists for inhibition of platelet aggregation (I): in vitro effects on platelets.

ADP plays a key role in platelet aggregation which has led to the development of antiplatelet drugs that target the P2Y12 receptor. The aim of this study was to characterize the effects of two novel P2Y12 receptor antagonists, BX 667 and its active metabolite BX 048, on platelets. BX 667 and BX 048 block the binding of 2MeSADP to platelets and antagonize ADP-induced platelet aggregation in human, dog and rat washed platelets. Both compounds were shown to be reversible inhibitors of platelet aggregation. BX 048 prevents the decrease in cAMP induced by treatment of platelets with ADP. The specificity of BX 667 and BX 048 was demonstrated against cell lines expressing P2Y1 and P2Y6 as well as against a panel of receptors and enzymes. Taken all together these data show that both BX 048 and BX 667 are potent P2Y12 antagonists with high specificity which, in the accompanying paper are demonstrated to behave predictably in vivo.

A dual-labeling method to quantify unscheduled DNA synthesis in primary cells.

Unscheduled DNA synthesis (UDS) has been used as an endpoint for measuring DNA damage in vitro and in vivo. Determination of UDS is regarded as a reliable genotoxicity assay by regulatory agencies including US FDA and EPA. In this study, we have developed an improved UDS assay to detect DNA damage and repair processes upon chemical exposure. We utilized a dual-labeling procedure in which fluorescent DAPI stained nuclei of live cells and [(3)H]thymidine labeled cells undergoing new DNA synthesis. The occurrence of UDS in cells was quantified by either manual nucleus counting or net intensity approaches. This assay was validated by testing known genotoxic compounds 2-acetylaminofluorene (2-AAF), ethylmethanesulfonate (EMS), and N-nitrosodimethylamine (NDL) in primary rat hepatocytes as well as in confluent human mammary epithelial cells. In addition, fluorescent labeling of nuclei DNA helped to distinguish apoptotic cells from non-apoptotic cells. Chemical effects on cell functions were also examined by conducting the cytotoxicity assay along with the UDS assay. To conclude, the dual-labeling UDS assay offers advantages of reduced subjective bias, increasing sensitivity and reproducibility. The assay is suitable for testing compounds in higher capacity format with much less compound needed.

Changing Practice Evaluation-Stage 1 Seminoma: Outcomes With Adjuvant Treatment Versus Surveillance: Risk Factors for Recurrence and Optimizing Follow-up Protocols-Experience From a Supraregional Center.

BACKGROUND: Stage 1 seminoma is frequently cured by radical orchiectomy; however, the management strategies after this diagnosis vary in terms of the use of adjuvant treatment and the nature of the follow-up protocols. We analyzed stage 1 seminomas treated in the Thames Valley Cancer Network for outcomes to determine whether any factors are predictive of recurrence. We also studied relapses to determine the optimal follow-up schedule and protocol. MATERIALS AND METHODS: Data were obtained from centers within the Thames Valley Cancer Network for a 12-year period from 2004 to 2016. We identified 501 patients with stage 1 seminoma. RESULTS: Relapses occurred in 6.2% of the patients receiving adjuvant treatment and 6.1% of those who did not. The only statistically significant predictive factor identified for relapse was rete testis invasion, and the risk was greater when only stromal rete invasion was included, rather than pagetoid as well. A trend was seen toward an increased risk with increased tumor size, but the difference was not statistically significant. Recurrences developed within the first 2 years after surgery in nearly 75% of cases and were identified through surveillance computed tomography scans in 54.8% of the patients. All relapses were treated curatively. CONCLUSION: Active surveillance leads to excellent outcomes for stage 1 seminoma; however, adjuvant treatment should be reserved for those with high-risk disease. Follow-up schedules should include computed tomography imaging during the first 3 years, long-term measurement of tumor markers, and mechanisms for patients to be seen promptly should symptoms of tumor recurrence occur.

Thiophene-anthranilamides as highly potent and orally available factor Xa inhibitors.

There remains a high unmet medical need for a safe oral therapy for thrombotic disorders. The serine protease factor Xa (fXa), with its central role in the coagulation cascade, is among the more promising targets for anticoagulant therapy and has been the subject of intensive drug discovery efforts. Investigation of a hit from high-throughput screening identified a series of thiophene-substituted anthranilamides as potent nonamidine fXa inhibitors. Lead optimization by incorporation of hydrophilic groups led to the discovery of compounds with picomolar inhibitory potency and micromolar in vitro anticoagulant activity. Based on their high potency, selectivity, oral pharmacokinetics, and efficacy in a rat venous stasis model of thrombosis, compounds ZK 814048 (10b), ZK 810388 (13a), and ZK 813039 (17m) were advanced into development.

A novel inhibitor of activated thrombin activatable fibrinolysis inhibitor (TAFIa) - part II: enhancement of both exogenous and endogenous fibrinolysis in animal models of thrombosis.

We have discovered a novel small-molecule TAFIa inhibitor, BX 528, which is potent, highly selective against other carboxypeptidases and safe. The present study was to determine if BX 528 can enhance exogenous and endogenous thrombolysis in four different animal models. In the first three models, a thrombus was induced by FeCl (2) (dogs) or laser (rats) injury of the femoral artery, or formed ex vivo and implanted in the jugular vein in rabbits. A low dose of exogenous t-PA was given to induce a low-level thrombolysis on an established thrombus. Co-treatment with BX 528 further enhanced the thrombolytic effects induced by the exogenous t-PA and, thus, reduced thrombosis in all three animal models. In a second rat model, fibrin deposition in the lungs was induced by batroxobin, which was spontaneously resolved in 30 minutes due to the activation of endogenous fibrinolysis. Pre-treatment with lipopolysaccharide (LPS) attenuated this spontaneous fibrinolysis. Co-treatment with 10 mg/kg BX 528 prevented the LPS-induced attenuation of endogenous fibrinolysis. Thus, these studies demonstrated that inhibition of TAFIa by BX 528, our newly discovered small-molecule TAFIa inhibitor, enhanced both the exogenous (induced by a low dose of t-PA) and endogenous (LPS-induced resistance) thrombolysis without increasing the bleeding risk in four different animal models of thrombosis in different species (rat, dog and rabbit) employing different thrombogenic stimuli (FeCl (2) , laser, ex vivo and batroxobin) to induce thrombus formation in different tissues (artery, vein and lung microcirculation).

A novel P2Y(12) adenosine diphosphate receptor antagonist that inhibits platelet aggregation and thrombus formation in rat and dog models.

Irreversible platelet inhibitors, such as aspirin and clopidogrel, have limited anti-thrombotic efficacy in the clinic due to their bleeding risk. We have developed an orally active reversible P2Y(12) receptor antagonist, BX 667. The aim of this study was to determine if the reversible antagonist BX 667 had a greater therapeutic index than the irreversible P2Y(12) receptor antagonist clopidogrel. Since BX 667 is rapidly converted to its active metabolite BX 048 in rats, we first injected BX 048 intravenously (iv) in a rat arterial venous (A-V) shunt model of thrombosis. BX 048 dose- and concentration-dependently attenuated thrombosis. When administered orally, BX 667 and clopidogrel had similar efficacy, but BX 667 caused less bleeding than clopidogrel. In a rat model of a platelet-rich thrombus induced by vessel injury with FeCl(2), both BX 667 and clopidogrel exhibited higher levels of thrombus inhibition after oral administration compared to their potency in the A-V shunt model. Again, BX 667 caused less bleeding than clopidogrel. In a dog cyclic flow model, iv injection of either BX 667 or clopidogrel dose-dependently reduced thrombus formation with lower bleeding for BX 667 than clopidogrel. Inhibition of thrombosis was highly correlated with inhibition of ADP-induced platelet aggregation in these animal models. In dogs pre-treated with aspirin, BX 667 maintained its wider therapeutic index, measured by inhibition of platelet aggregation over bleeding, compared to the aspirin-clopidogrel combination. These data demonstrate that the reversible P2Y(12) receptor antagonist, BX 667, has a wider therapeutic index than clopidogrel in experimental models of thrombosis.

Monocyte chemoattractant protein-1 or macrophage inflammatory protein-1alpha deficiency does not affect angiotensin II-induced intimal hyperplasia in carotid artery ligation model.

BACKGROUND: Angiotensin II (Ang II) promotes atherosclerotic vascular diseases, in which proinflammatory and proliferative effects play a major pathogenic role. Ang II up-regulates chemokines, such as monocyte chemoattractant protein (MCP)-1 and macrophage inflammatory protein (MIP)-1alpha, which are important pro-inflammatory factors mediating infiltration of inflammatory cells into atherosclerotic lesion. The aim of the present study was to determine whether the presence of MCP-1 or MIP-1alpha is essential in Ang II-induced intimal hyperplasia in the carotid artery ligation model. METHODS: Six-month-old male C57BL/6-, MCP-1-, or MIP-1alpha-deficient mice underwent ligation of the common left carotid artery and were randomly assigned to receive either vehicle or Ang II (1.4 mg kg(-1) day(-1)) via a subcutaneously implanted osmotic infusion pump (model 2004, Alzet) for 4 weeks. RESULTS: Ang II not only increased MCP-1 and MIP-1alpha production but also enhanced neo-intimal formation, media thickness, and adventitia development in the ligated carotid arteries in C57BL/6 mice. However, MCP-1 or MIP-1alpha deficiency failed to affect intimal hyperplasia in vascular remodeling. CONCLUSION: These results indicate that MCP-1 or MIP-1alpha may not be essential in mediating the proliferative effects of Ang II, a major pathological changes in intimal hyperplasia in the carotid artery ligation model.

Endothelial NO synthase deficiency promotes smooth muscle progenitor cells in association with upregulation of stromal cell-derived factor-1alpha in a mouse model of carotid artery ligation.

BACKGROUND: Endothelial NO deficiency (endothelial NO synthase [eNOS]-knockout [KO]) enhanced smooth muscle cell (SMC)-rich neointimal lesion formation in a mouse model of carotid artery ligation (CAL). Recent evidence indicated that stromal cell-derived factor-1alpha (SDF-1alpha)-mediated recruitment of circulating SMC progenitor cells substantially contributed to the SMC-rich neointimal hyperplasia induced by vascular injury. The goal of this study was to investigate the effects of eNOS deficiency on the expression of SDF-1alpha and mobilization of circulating SMC progenitor cells in CAL model. METHODS AND RESULTS: Two- to 3-month-old C57BL/6J wild-type (WT) and eNOS-KO mice were evaluated 1, 2, or 4 weeks after CAL. CAL-induced expression of SDF-1alpha, as detected by immunohistochemical staining and further quantified by ELISA in the ligated carotid arteries, was moderate and transient with a peak at 1 week in WT mice. SDF-1alpha expression was significantly higher at 1 week and persisted through 2 weeks in eNOS-KO mice. CAL was associated with increased circulating stem cell antigen-1(+) (Sca-1(+))/c-Kit(-)/Lin- cells (interpreted as SMC progenitor cells), which peaked at 1 week in WT mice. This effect was also significantly greater and longer-lasting in eNOS-KO than WT mice. The number of circulating Sca-1(+)/c-Kit(-)/Lin- cells was positively correlated with the expression of SDF-1alpha but not vascular endothelial growth factor in the ligated carotid arteries. Furthermore, immunostaining showed abundant Sca-1-positive cells in the adventitia of the 1-week ligated carotid arteries from eNOS-KO mice but not in WT mice. We also determined that eNOS deficiency enhanced CAL-induced intimal cell proliferation in the ligated arteries as detected by proliferating cell nuclear antigen staining but did not induce cell apoptosis as detected by staining for active caspase-3. CONCLUSIONS: Our results indicate that eNOS deficiency exacerbates CAL-induced expression of SDF-1alpha and its receptor CXCR4. This is correlated with an increase in Sca-1(+) cells in peripheral blood and adventitia, which may contribute to vascular remodeling and SMC-rich neointimal lesion formation. This suggests that constitutive eNOS inhibits SDF-1alpha expression and provides an important vasculoprotective mechanism for intact endothelium to limit SMC proliferation and recruitment in response to vascular injury.

Cell-based assays for profiling activity and safety properties of cancer drugs.

INTRODUCTION: Our goal was to establish versatile and high capacity assays to characterize activity and toxicity of chemotherapeutics. The major anti-cancer activity indicators of these agents included inhibition of proliferation and induction of apoptosis to cancer cells. In addition, cytotoxicity and myelosuppressive activity to normal cells were parameters to evaluate toxicity of these drugs. METHODS: Using a panel of cell-based assay systems, we investigated activity and toxicity properties of selected cancer drugs. Drug effects on a number of normal and cancer cell types from human origin were evaluated. RESULTS: Topoisomerase inhibitors (camptothecin, doxorubicin and etoposide) and microtubule inhibitors (colchicine and paclitaxel) showed anti-proliferation activity and induced apoptosis in MDA-231 cancer cells. Except for doxorubicin, these drugs had relatively low toxicity to normal cells because the dosage required for cytotoxicity EC(50) was >200-folds higher than the dosage for anti-proliferation EC(50) in cancer cells (MDA-231, HL60). However, these drugs were potent inducers of myelotoxicity in human bone marrow progenitor cells. In comparison, the DNA alkylating agents (cisplatin and carboplatin) were less potent proliferation inhibitors (EC(50)>10 microM) in MDA-231 cells and they were also less myelosuppressive. DISCUSSION: Using marketed drugs as examples, our study established a multiple assay platform for profiling in vitro properties of cancer drugs. In drug discovery, such a platform will help to expedite lead selection at early stage.

Human primary renal cells as a model for toxicity assessment of chemo-therapeutic drugs.

Chemo-therapeutic drugs act on cancerous and normal cells non-selectively and often cause organ impairments during treatment. Improving safety or reducing toxicity becomes an important challenge for developing better anticancer drugs. In the present study, effects of selected anticancer drugs (camptothecin, doxorubicin, colchicine, paclitaxel, cisplatin, and carboplatin) on cell viability and proliferation was investigated. The anti-proliferative activity of each drug on cancer cells (human hepatoma HepG2) and human primary renal proximal tubule cells (hRPTECs and LLC-PK1) was determined with the [(3)H]thymidine incorporation assay. Results indicated all six drugs blocked cell proliferation in cancer and normal cells. When the anti-proliferation potency was ranked in hRPTECs based on EC50 values, camptothecin is the most potent, followed by doxorubicin, paclitaxel, colchicine, cisplatin and carboplatin. Cytotoxicity of drugs to hRPTECs was assessed with the ATP bioluminescence assay. Doxorubicin and cisplatin were known to induce nephrotoxicity in vivo and they were indeed cytotoxic to hRPTECs in our study with EC50 values at 11.2 and 39.6 microM. All other drugs are not cytotoxic in the concentrations tested. These drugs typically displayed separation of EC50s between potency (anti-proliferation) and cytotoxicity. The dose separation provides a concentration range for each drug to act on cell proliferation without induction of significant cytotoxicity. Our results suggest that hRPTEC system can serve as an in vitro model for assessing potential nephrotoxicity of chemo-therapeutic drugs.

Is Erectile Dysfunction an Example of Abnormal Endothelial Function?

Erectile dysfunction (ED) affects approximately half of men during middle age. Erectile dysfunction is often an early symptom of systemic vascular disease, which may precipitate significant cardiac events. The pathophysiology of ED and cardiovascular disease is closely linked. Endothelial dysfunction occurs at an early stage in ED and cardiovascular disease (CVD). In normal conditions, nitric oxide dependent and independent mechanisms regulate penile vascular tone ensuring an appropriate balance of vasoconstriction and vasodilatation. A normal endothelium is responsible for mediating the effect of pro-erectile mediators derived from the endothelium and is critical in normal erectile function. Endothelial dysfunction disrupts the homeostatic mechanisms responsible for regulation of smooth muscle contraction and penile vascular tone. Reduced bioavailability of nitric oxide (NO) occurs as a response to endothelial damage. Phosphodiesterases further degrade levels of cyclic guanosine monophosphate (cGMP) and impair smooth muscle relaxation and erectile function. A number of endothelium derived NO independent mediators of erectile function have been described and are known to contribute to ED in the presence of endothelial damage. This review provides an up to date analysis of the role of the endothelium in ED describing the pathways involved and how these represent current and potential therapeutic targets.

Enalapril attenuates angiotensin II-induced atherosclerosis and vascular inflammation.

Angiotensin converting enzyme (ACE) inhibitors prevent a wide variety of key events underlying atherogenesis. Whether these actions depend solely on reduction of angiotensin II (Ang II) generation is still to be determined. This study was undertaken to determine whether enalapril, an ACE inhibitor, prevents atherosclerosis and vascular inflammation induced by Ang II in apolipoprotein E-deficient (apoE-KO) mice. Subcutaneous infusion of Ang II (1.44 mg/(kg day)) for 4 weeks increased blood pressure and accelerated atherosclerosis development in the carotid arteries. The expression of the endothelial adhesion molecules E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), as well as the chemokines monocyte chemotactic protein-1 (MCP-1) and macrophage-colony stimulating factor (M-CSF) was up-regulated in the aortas of Ang II-treated mice. Enalapril co-treatment (25 mg/(kg day), in drinking water) prevented the development of atherosclerosis without affecting blood pressure or circulating cholesterol. In addition to preventing the Ang II-induced over-expression of adhesion molecules and chemokines in the aorta, enalapril up-regulated the expression of peroxisome proliferator-activated receptors (PPARs)-alpha and -gamma, potential anti-inflammatory transcription factors. In the aortic arch, a lesion-prone site, the co-treatment with enalapril reduced the percentage of arterial wall occupied by macrophages and foam cells, medial sclerosis and elastin reduplication. Together, these data suggest an important role for Ang II-independent mechanisms in the antiatherogenic and anti-inflammatory effects of ACE inhibitors.

17 Beta-estradiol attenuates development of angiotensin II-induced aortic abdominal aneurysm in apolipoprotein E-deficient mice.

OBJECTIVE: Angiotensin II (Ang II) promotes vascular inflammation, accelerates atherosclerosis, and induces abdominal aortic aneurysm (AAA). These changes were associated with activation of nuclear factor (NF)-kappaB-mediated induction of proinflammatory genes. The incidence of AAA in this model was higher in male than in female mice, and the vascular effects of estrogen may be associated with anti-inflammatory actions. The present study was undertaken to test the hypothesis that estrogen can attenuate Ang II-induced AAA in apolipoprotein E-deficient mice via its anti-inflammatory mechanism. METHODS AND RESULTS: Infusion of Ang II (1.44 mg/kg per d for 1 month) induced AAA in 90% of the animals (n=20) with an expansion of the suprarenal aorta (diameter 1.9+/-0.14 mm versus <1 mm in normal mice). In mice treated with 17beta-estradiol (E2, 0.25-mg subcutaneous pellets), Ang II induced AAA only in 42% of the animals (n=19) with a significant reduction of average diameters of the suprarenal aorta (1.5+/-0.14 mm). E2 also decreased the expressions of intracellular adhesion molecule-1, vascular cellular adhesion molecule-1, E-selectin, monocyte chemotactic protein-1, and macrophage-colony stimulating factor in the aorta. CONCLUSIONS: These data suggest that attenuation of AAA by E2 is associated with inhibition of proinflammatory gene expression.

Noninvasive measurement of abdominal aortic aneurysms in intact mice by a high-frequency ultrasound imaging system.

Mouse models of abdominal aortic aneurysm (AAA) have been commonly used in many laboratories for studying molecular mechanisms of AAA formation and development, as well as for testing novel therapeutic agents in the treatment of AAA. However, because of the small size of the animal, the quantification and characterization of AAA development and progress is difficult, time-consuming and requires the sacrifice of the experimental animals. We report here a noninvasive method to detect and measure AAA in mice using a high-frequency ultrasound (US) imaging system specifically designed for microimaging of the mice (Vevo 660; VisualSonics, Toronto, ONT, Canada). A total of 21 male apolipoprotein-E-deficient mice were chronically infused with angiotensin II (1.44 mg/kg daily) for 28 days to induce AAA formation. A 2-D echo image of the abdominal aorta was acquired at longitudinal and transverse planes, followed immediately by post mortem dissection of the abdominal aorta for direct measurements. The US images clearly showed a bulge-like expansion localized specifically in the suprarenal region of the abdominal aorta, with a shape strikingly similar to that of the aorta dissected post mortem. In addition, the US images can also provide measurements of the luminal diameter and wall thickness of the abdominal aorta. The average dimensions of the abdominal aorta were not significantly different between the US and post mortem measurements, nor between the transverse and longitudinal US images. The different types of the measurements are also highly correlated with each other, with a linear correlation (r) between 0.7 and 0.9. Thus, we have established and validated a novel application to noninvasively measure AAA development and progress in a mouse model using a high-frequency US imaging system that has the advantages of low cost, rapid imaging speed, reproducibility and high resolution, and makes repeated monitoring of the progress of AAA development over a time-course possible.