A case-control comparison of acute-phase peripheral blood gene expression in participants diagnosed with minor ischaemic stroke or stroke mimics.

BACKGROUND: Past studies suggest that there are changes in peripheral blood cell gene expression in response to ischaemic stroke; however, the specific changes which occur during the acute phase are poorly characterised. The current study aimed to identify peripheral blood cell genes specifically associated with the early response to ischaemic stroke using whole blood samples collected from participants diagnosed with ischaemic stroke (n = 29) or stroke mimics (n = 27) following emergency presentation to hospital. Long non-coding RNA (lncRNA), mRNA and micro-RNA (miRNA) abundance was measured by RNA-seq, and the consensusDE package was used to identify genes which were differentially expressed between groups. A sensitivity analysis excluding two participants with metastatic disease was also conducted. RESULTS: The mean time from symptom onset to blood collection was 2.6 h. Most strokes were mild (median NIH stroke scale score 2.0). Ten mRNAs (all down-regulated in samples provided by patients experiencing ischaemic stroke) and 30 miRNAs (14 over-expressed and 16 under-expressed in participants with ischaemic stroke) were significantly different between groups in the whole cohort and sensitivity analyses. No significant over-representation of gene ontology categories by the differentially expressed genes was observed. Random forest analysis suggested a panel of differentially expressed genes (ADGRG7 and miRNAs 96, 532, 6766, 6798 and 6804) as potential ischaemic stroke biomarkers, although modelling analyses demonstrated that these genes had poor diagnostic performance. CONCLUSIONS: This study provides evidence suggesting that the early response to minor ischaemic stroke is predominantly reflected by changes in the expression of miRNAs in peripheral blood cells. Further work in independent cohorts particularly in patients with more severe stroke is needed to validate these findings and investigate their clinical relevance.

Evaluation of quantitative biomarkers of aging in human PBMCs.

Functional decline with age contributes significantly to the burden of disease in developed countries. There is growing interest in the development of therapeutic interventions which slow or even reverse aging. Time and cost constraints prohibit the testing of a large number of interventions for health and lifespan extension in model organisms. Cell-based models of aging could enable high throughput testing of potential interventions. Despite extensive reports in the literature of cell properties that correlate with donor age, few are robustly observed across different laboratories. This casts doubt on the extent that aging signatures are captured in cultured cells. We tested molecular changes previously reported to correlate with donor age in peripheral blood mononuclear cells (PBMCs) and evaluated their suitability for inclusion in a panel of functional aging measures. The tested measures spanned several pathways implicated in aging including epigenetic changes, apoptosis, proteostasis, and intracellular communication. Surprisingly, only two markers correlated with donor age. DNA methylation age accurately predicted donor age confirming this is a robust aging biomarker. Additionally, the apoptotic marker CD95 correlated with donor age but only within subsets of PBMCs. To demonstrate cellular rejuvenation in response to a treatment will require integration of multiple read-outs of cell function. However, building a panel of measures to detect aging in cells is challenging and further research is needed to identify robust predictors of age in humans.

Association Between Serum MicroRNAs and Abdominal Aortic Aneurysm Diagnosis and Growth.

OBJECTIVE: This study aimed to examine the association between serum microRNAs (miRNAs) and diagnosis and growth of abdominal aortic aneurysm (AAA), and to test their diagnostic and prognostic value. METHODS: The expression levels of 800 miRNA tags were assessed in 108 patients with AAA, 12 age and sex matched healthy controls (HCs), and 12 patients with peripheral artery disease (PAD) using NanoString technology. Findings were assessed in an independent sample of 66 patients with AAA and 29 age and sex matched HCs by reverse transcriptase polymerase chain reaction. AAA growth was assessed by a median of three (interquartile range [IQR] 2, 3) repeat ultrasound scans over a median follow up of 1.1 (IQR 1.0, 2.0) years. The association between the miRNA and AAA diagnosis and growth was examined by regression and linear mixed effects analyses. The diagnostic and prognostic potential of the miRNAs were examined using area under the receiver operator characteristic curve (AUC), net re-classification index (NRI), and Cox hazard analyses. RESULTS: In comparison with HCs, a model combining clinical risk factors, let-7b-5p and miR-548n had an AUC of 98.0% (95% confidence interval [CI] 95.6 - 100.0; p = .003) for diagnosing AAA, which was a significant improvement over clinical risk factors alone (NRI 1.74; 95% CI 1.61 - 1.87; p < .001). Compared with PAD, a model combining clinical risk factors and miR-548n had an AUC of 99.6% (95% CI 98.9 - 100.0, p = .037) for diagnosing AAA, which was a significant improvement over clinical risk factors alone (NRI 1.79, 95% CI 1.68 - 1.91; p < .001). In the longitudinal cohort, none of the miRNAs were able to predict the likelihood of reaching surgical threshold diameter better than clinical risk factors alone. CONCLUSION: Serum let-7b-5p and miR548n significantly improved the ability to diagnose AAA. None of the miRNAs had independent prognosis value in predicting AAA growth.

Serum angiopoietin-1 concentration does not distinguish patients with ischaemic stroke from those presenting to hospital with ischaemic stroke mimics.

BACKGROUND: A previous study found that circulating angiopoietin-1 (angpt-1) concentrations were significantly lower in patients who had a recent ischaemic stroke compared to healthy controls. The primary aim of this study was to assess whether serum angpt-1 could be used as a diagnostic test of ischemic stroke in patients presenting to hospital as an emergency. Exploratory analyses investigated the association of proteins functionally related to angpt-1 (angpt-2, Tie-2, matrix metalloproteinase-9 and vascular endothelial growth factors A, C and D) with ischaemic stroke diagnosis. METHODS: Patients presenting to Townsville University Hospital for emergency assessment of stroke-like symptoms were consecutively recruited and provided a blood sample. After assessment by a consultant neurologist, patients were grouped into those who did, or did not have ischaemic stroke. The potential for serum angpt-1 to diagnose ischaemic stroke was assessed using receiver operator characteristic (ROC) curves. Cross-sectional analyses appraised inter-group differences in the serum concentration of other proteins. RESULTS: One-hundred and twenty-six patients presenting to Townsville University Hospital for emergency assessment of stroke-like symptoms were recruited (median time from symptom onset to hospital presentation: 2.6 (inter-quartile range: 1.2-4.6) hours). Serum angpt-1 had poor ability to diagnose ischaemic stroke in analyses using the whole cohort, or in sensitivity analyses (area under the ROC curve 0.51 (95% CI: 0.41-0.62) and 0.52 (95% CI: 0.39-0.64), respectively). No associations of serum angpt-1 concentration with ischaemic stroke severity, symptom duration or aetiology were observed. Serum concentrations of the other assessed proteins did not differ between patient groups. CONCLUSIONS: Serum angpt-1 concentration is unlikely to be useful for emergency diagnosis of ischaemic stroke.

Colchicine Does Not Reduce Abdominal Aortic Aneurysm Growth in a Mouse Model.

Background and Aims: The nacht domain, leucine-rich repeat, and pyrin domain-containing protein 3 (NLRP3) inflammasome is upregulated in human abdominal aortic aneurysm (AAA), but its pathogenic role is unclear. The aims of this study were firstly to examine whether the inflammasome was upregulated in a mouse model of AAA and secondly to test whether the inflammasome inhibitor colchicine limited AAA growth. Methods: AAA was induced in eight-week-old male C57BL6/J mice with topical application of elastase to the infrarenal aorta and oral 3-aminopropionitrile (E-BAPN). For aim one, inflammasome activation, abdominal aortic diameter, and rupture were compared between mice with AAA and sham controls. For aim two, 3 weeks after AAA induction, mice were randomly allocated to receive colchicine (n = 28, 0.2 mg/kg/d) or vehicle control (n = 29). The primary outcome was the rate of maximum aortic diameter increase measured by ultrasound over 13 weeks. Results: There was upregulation of NLRP3 markers interleukin- (IL-) 1ß (median, IQR; 15.67, 7.11-22.60 pg/mg protein versus 6.87, 4.54-11.60 pg/mg protein, p = .048) and caspase-1 (109, 83-155 relative luminosity units (RLU) versus 45, 38-65 RLU, p < .001) in AAA samples compared to controls. Aortic diameter increase over 80 days (mean difference, MD, 4.3 mm, 95% CI 3.3, 5.3, p < .001) was significantly greater in mice in which aneurysms were induced compared to sham controls. Colchicine did not significantly limit aortic diameter increase over 80 days (MD -0.1 mm, 95% CI -1.1, 0.86, p = .922). Conclusions: The inflammasome was activated in this mouse model of AAA; however, daily oral administration of colchicine did not limit AAA growth.

Association of Diagnosis of Depression and Small Abdominal Aortic Aneurysm Growth.

BACKGROUND: Depression is associated with an increased risk of cardiovascular events but its association with abdominal aortic aneurysm (AAA) progression is unknown. This study examined if a diagnosis of depression was association with more rapid AAA growth. METHODS: Patients with small AAA measuring between 30 and 50 mm were recruited from surveillance programs at 4 Australian centres. Maximum AAA diameter was measured by ultrasound imaging using a standardised and reproducible protocol to monitor AAA growth. Depression was defined from medical records of treatment for depression at recruitment. Linear mixed effects modelling was performed to examine the independent association of depression with AAA growth. A propensity matched sub-analysis was performed. RESULTS: A total of 574 participants were included of whom 73 (12.7%) were diagnosed with depression. Participants were followed with a median of 3 (Inter-quartile range (IQR): 2, 5) ultrasound scans for a median of 2.1 (IQR: 1.1, 3.5) years. The unadjusted model suggested that annual AAA growth was non-significantly reduced (mean difference: -0.3 mm/year; 95% confidence interval (CI): -0.7, 0.2; P = 0.26) in participants with a diagnosis of depression compared to other participants. After adjustment for covariates, depression was not significantly associated with AAA growth (mean difference: -0.3 mm/year; 95% CI: -0.8, 0.2; P = 0.27). Findings were similar in the propensity matched sub-analysis. Sensitivity analyses investigating the impact of initial AAA diameter and follow up on the association of depression with AAA growth found no interaction. CONCLUSIONS: This study suggested that depression was not associated with faster AAA growth.

Immunosuppressive drugs for nontransplant comorbidities are not associated with abdominal aortic aneurysm growth.

Background: In the present study, we examined the association of immunosuppressant drug prescriptions with the growth of small abdominal aortic aneurysms (AAAs). Methods: Participants with an AAA measuring between 30 and 50 mm were recruited from four Australian centers. AAA growth was monitored by ultrasound. The immunosuppressant drugs included conventional disease-modifying antirheumatic drugs (eg, methotrexate, sulfasalazine, leflunomide), steroids, hydroxychloroquine, other immunosuppressant drugs (eg, cyclosporine, azacitidine), or a combination of these drugs. Linear mixed effects modeling was performed to examine the independent association of an immunosuppressant prescription with AAA growth. A subanalysis examined the association of steroids with AAA growth. Results: Of the 621 patients, 34 (5.3%) had been prescribed at least one (n = 26) or more (n = 8) immunosuppressant drug and had been followed up for a median period of 2.1 years (interquartile range, 1.1-3.5 years), with a median of three ultrasound scans (interquartile range, two to five ultrasound scans). No significant difference was found in AAA growth when stratified by a prescription of immunosuppressant drugs on either unadjusted (mean difference, 0.2 mm/y; 95% confidence interval [CI], -0.4 to 0.7; P = .589) or risk factor-adjusted (mean difference, 0.2 mm/y; 95% CI, -0.3 to 0.7; P = .369) analyses. The findings were similar for the unadjusted (mean difference, 0.0 mm/y; 95% CI, -0.7 to 0.7; P = .980) and risk factor-adjusted (mean difference, 0.1 mm/y; 95% CI, -0.6 to 0.7; P = .886) subanalyses focused on steroid use. Conclusions: The results from this study suggest that AAA growth is not affected by immunosuppressant drug prescription. Studies with larger sample sizes are needed before reliable conclusions can be drawn.

A Systematic Review and Meta-Analysis of the Effect of Pentagalloyl Glucose Administration on Aortic Expansion in Animal Models.

BACKGROUND: The aim of this systematic review was to pool evidence from studies testing if pentagalloyl glucose (PGG) limited aortic expansion in animal models of abdominal aortic aneurysm (AAA). METHODS: The review was conducted according to the PRISMA guidelines and registered with PROSPERO. The primary outcome was aortic expansion assessed by direct measurement. Secondary outcomes included aortic expansion measured by ultrasound and aortic diameter at study completion. Sub analyses examined the effect of PGG delivery in specific forms (nanoparticles, periadventitial or intraluminal), and at different times (from the start of AAA induction or when AAA was established), and tested in different animals (pigs, rats and mice) and AAA models (calcium chloride, periadventitial, intraluminal elastase or angiotensin II). Meta-analyses were performed using Mantel-Haenszel's methods with random effect models and reported as mean difference (MD) and 95% confidence intervals (CIs). Risk of bias was assessed with a customized tool. RESULTS: Eleven studies reported in eight publications involving 214 animals were included. PGG significantly reduced aortic expansion measured by direct observation (MD: -66.35%; 95% CI: -108.44, -24.27; p = 0.002) but not ultrasound (MD: -32.91%; 95% CI: -75.16, 9.33; p = 0.127). PGG delivered intravenously within nanoparticles significantly reduced aortic expansion, measured by both direct observation (MD: -116.41%; 95% CI: -132.20, -100.62; p < 0.001) and ultrasound (MD: -98.40%; 95% CI: -113.99, -82.81; p < 0.001). In studies measuring aortic expansion by direct observation, PGG administered topically to the adventitia of the aorta (MD: -28.41%; 95% CI -46.57, -10.25; p = 0.002), studied in rats (MD: -56.61%; 95% CI: -101.76, -11.46; p = 0.014), within the calcium chloride model (MD: -56.61%; 95% CI: -101.76, -11.46; p = 0.014) and tested in established AAAs (MD: -90.36; 95% CI: -135.82, -44.89; p < 0.001), significantly reduced aortic expansion. The findings of other analyses were not significant. The risk of bias of all studies was high. CONCLUSION: There is inconsistent low-quality evidence that PGG inhibits aortic expansion in animal models.

Editor's Choice - Association Between Metformin Prescription and Abdominal Aortic Aneurysm Growth and Clinical Events: a Systematic Review and Meta-Analysis.

OBJECTIVE: A meta-analysis of the association between metformin prescription and abdominal aortic aneurysm (AAA) growth and events (rupture or surgical repair) was performed. METHODS: Open source databases were searched for observational studies reporting the association between metformin prescription and AAA growth or events. Meta-analyses were performed using random effects models. The risk of bias of included studies was assessed using a quality assessment tool developed in a previous systematic review. Sensitivity analyses restricted to people with diabetes, leave one out analyses, and an individual patient risk factor adjusted sub-analysis were performed. Funnel plots assessed reporting bias. RESULTS: Eight studies comprising 153 553 patients were included, of whom 35 240 were and 118 313 were not prescribed metformin. Pooled weighted mean (± standard deviation) AAA growth was significantly reduced in patients prescribed metformin (0.9 ± 0.4 mm/year) compared with those not receiving the medication (1.8 ± 0.4 mm/year; weighted mean difference [WMD] 0.8 mm/year, 95% confidence interval [CI] 0.5 - 1.1; p < .001; I2 = 89%). Leave one out analysis suggested that the significance of findings did not change after removal of individual studies. A sub-analysis within people with diabetes suggested that metformin reduced AAA growth (WMD 0.7 mm/year, 95% CI 0.3 - 1.0). Metformin prescription was associated with a reduced risk of AAA events (risk ratio 0.6, 95% CI 0.4 - 0.9, p = .028). Three, four, and one studies had low, moderate, and high risk of bias, respectively. Individual patient data analysis suggested that metformin prescription slowed annual AAA growth by 0.5 mm/year (95% CI 0.2 - 0.7). The GRADE summary suggested that the certainty of evidence that metformin limited AAA growth and prevented AAA events was very low. CONCLUSION: Observational studies suggest that metformin prescription is associated with a clinically important significant reduction in both growth and clinically relevant events in people with AAA. These findings support the need for randomised trials to examine the benefit of metformin.

Symptomatic Bradycardia in Covid-19 Hospitalized Patients: A Case Series.

SARS COV-2 infection has become a global threat. Cardiovascular manifestations associated with Covid-19 have been noted in several publications, and bradycardia related to Covid-19 is a commonly reported complication. This study reports six serial cases of bradycardia attributable to Covid-19; four of them developed complete atrioventricular block. These patients experienced clinical symptoms related to bradycardia and initially required permanent pacemaker implantation. However, one patient did not require permanent pacing later on due to spontaneous conversion to sinus rhythm. In comparison, the other two patients who developed transient sinus bradycardia experienced a self-limiting condition during their hospitalization period without requiring any cardiac pacing device or medication to increase heart rate. Complete atrioventricular block and transient sinus bradycardia in these patients, despite not having any history of bradycardia, might be due to complex processes in the systemic inflammatory response in Covid-19. Cardiac monitoring, hemodynamic evaluation, and strategy for permanent pacemaker in these patients should be treated on a case-by-case basis.

Network Meta-Analysis Comparing the Outcomes of Treatments for Intermittent Claudication Tested in Randomized Controlled Trials.

Background No network meta-analysis has considered the relative efficacy of cilostazol, home exercise therapy, supervised exercise therapy (SET), endovascular revascularization (ER), and ER plus SET (ER+SET) in improving maximum walking distance (MWD) over short- (<1 year), moderate- (1 to <2 years), and long-term (≥2 years) follow-up in people with intermittent claudication. Methods and Results A systematic literature search was performed to identify randomized controlled trials testing 1 or more of these 5 treatments according to Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. The primary outcome was improvement in MWD assessed by a standardized treadmill test. Secondary outcomes were adverse events and health-related quality of life. Network meta-analysis was performed using the gemtc R statistical package. The Cochrane collaborative tool was used to assess risk of bias. Forty-six trials involving 4256 patients were included. At short-term follow-up, home exercise therapy (mean difference [MD], 89.4 m; 95% credible interval [CrI], 20.9-157.7), SET (MD, 186.8 m; 95% CrI, 136.4-237.6), and ER+SET (MD, 326.3 m; 95% CrI, 222.6-430.6), but not ER (MD, 82.5 m; 95% CrI, -2.4 to 168.2) and cilostazol (MD, 71.1 m; 95% CrI, -24.6 to 167.9), significantly improved MWD (in meters) compared with controls. At moderate-term follow-up, SET (MD, 201.1; 95% CrI, 89.8-318.3) and ER+SET (MD, 368.5; 95% CrI, 195.3-546.9), but not home exercise therapy (MD, 99.4; 95% CrI, -174.0 to 374.9) or ER (MD, 84.2; 95% CrI, -35.3 to 206.4), significantly improved MWD (in meters) compared to controls. At long-term follow-up, none of the tested treatments significantly improved MWD compared to controls. Adverse events and quality of life were reported inconsistently and could not be meta-analyzed. Risk of bias was low, moderate, and high in 4, 24, and 18 trials respectively. Conclusions This network meta-analysis suggested that SET and ER+SET are effective at improving MWD over the moderate term (<2 year) but not beyond this. Durable treatments for intermittent claudication are needed.

Effect of disease modifying anti-rheumatic drugs on major cardiovascular events: a meta-analysis of randomized controlled trials.

Disease modifying anti-rheumatic drugs (DMARDs) were developed to treat joint inflammation. There is growing evidence that anti-inflammatory drugs prevent major cardiovascular events (MACE). The aim of this systematic review and meta-analysis was to examine whether DMARDs reduce the risk of MACE. A systematic literature search was performed to identify randomized controlled trials (RCTs) testing the effect of DMARDs on cardiovascular events. The primary outcome was MACE defined as the first occurrence of non-fatal myocardial infarction (MI), non-fatal stroke or cardiovascular death. Secondary outcomes were myocardial infarction or stroke alone and all-cause mortality. Safety was assessed by fatal or life threatening infection. Meta-analyses were performed using random effect models and reported as risk ratios (RR) and 95% confidence intervals (CI). Study quality and publication bias were assessed using the Cochrane Collaboration's tool for assessing risk of bias and funnel plots. Twelve RCTs involving 18,056 participants testing three different DMARDs subclasses (Tumor Necrosis Factor inhibitors-4 trials; Janus Kinase inhibitors-5 trials; Interleukin inhibitors-3 trials) were included. Meta-analysis suggested that none of the DMARD subclasses had any effect on MACE, MI alone, stroke alone, risk of fatal or life threatening infection or death. Risk of bias was high, low and unclear in five, six and one studies respectively. Funnel plots suggested a low possibility of publication bias. This meta-analysis suggests that DMARDs do not affect the incidence of MACE. More trials are needed for firm conclusions.

Systematic Review and Meta-Analysis of Interventions to Slow Progression of Abdominal Aortic Aneurysm in Mouse Models.

[Figure: see text].

Animal models of ischemic limb ulcers: a systematic review and meta-analysis.

The aims of this systematic review were to assess the clinical relevance and quality of previously published animal models of ischemic ulceration and examine the available evidence for interventions improving ulcer healing in these models. Publicly available databases were searched for original studies investigating the effect of limb ischemia on wound healing in animal models. The quality of studies was assessed using two tools based on the Animal research: Reporting of In Vivo Experiments (ARRIVE) guidelines and the clinical relevance of the models. A total of 640 wounds (ischemic=314; non-ischemic=326) were assessed in 252 animals (92 mice, 140 rats, 20 rabbits) from 7 studies. Meta-analyses showed that wound healing was consistently delayed by ischemia at all time-points examined (day-7 standard median difference (SMD) 5.36, 95% CI 3.67 to 7.05; day-14 SMD 4.50, 95% CI 2.90 to 6.10 and day-21 SMD 2.53, 95% CI 1.25 to 3.80). No significant difference in wound healing was observed between 32 diabetic and 32 non-diabetic animals with ischemic wounds. Many studies lacked methods to reduce bias, such as outcome assessors blinded to group allocation and sample size calculations and clinically relevant model characteristics, such as use of older animals and a peripheral location of the wound. Five different interventions were reported to improve wound healing in these models. The impaired wound healing associated with limb ischemia can be modeled in a variety of different animals. Improvements in study design could increase clinical relevance, reduce bias and aid the discovery of translatable therapies.

Systematic review and meta-analysis of mouse models of diabetes-associated ulcers.

Mouse models are frequently used to study diabetes-associated ulcers, however, whether these models accurately simulate impaired wound healing has not been thoroughly investigated. This systematic review aimed to determine whether wound healing is impaired in mouse models of diabetes and assess the quality of the past research. A systematic literature search was performed of publicly available databases to identify original articles examining wound healing in mouse models of diabetes. A meta-analysis was performed to examine the effect of diabetes on wound healing rate using random effect models. A meta-regression was performed to examine the effect of diabetes duration on wound healing impairment. The quality of the included studies was also assessed using two newly developed tools. 77 studies using eight different models of diabetes within 678 non-diabetic and 720 diabetic mice were included. Meta-analysis showed that wound healing was impaired in all eight models. Meta-regression suggested that longer duration of diabetes prior to wound induction was correlated with greater degree of wound healing impairment. Pairwise comparisons suggested that non-obese diabetic mice exhibited more severe wound healing impairment compared with db/db mice, streptozotocin-induced diabetic mice or high-fat fed mice at an intermediate stage of wound healing (p<0.01). Quality assessment suggested that the prior research frequently lacked incorporation of key clinically relevant characteristics. This systematic review suggested that impaired wound healing can be simulated in many different mouse models of diabetes but these require further refinement to become more clinically relevant.

A volume-pressure tail cuff method for hemodynamic parameters: Comparison of restraint and light isoflurane anesthesia in normotensive male Lewis rats.

INTRODUCTION: A volume-pressure sensor and tail-cuff method for monitoring blood pressure is non-invasive and inexpensive. This method requires animals to be restrained or subjected to anesthesia, but comparative effects of these manipulations on hemodynamic parameters have not been documented. METHODS: Using a volume-pressure sensor and tail-cuff, we serially measured blood pressure and heart rate in normotensive adult male Lewis rats after light isoflurane-induced anesthesia (5% induction, 1% maintenance) and, following untrained restraint. Blood pressure was recorded until the acquisition of three complete measurements without the range of replicate mean arterial pressures exceeding 15 mmHg (steady-state). RESULTS: Averages for the entire series of consecutive measurements indicated that restraint yielded significantly higher systolic and diastolic blood pressure than anesthesia (P < .05), but heart rate was not affected. Following stabilization at steady-state, there were no significant differences in intra- or inter-day hemodynamic values between the restraint and isoflurane groups. The inter-day coefficient of variation for systolic pressure was 13-23% for isoflurane and 9-14% for restraint. Bland-Altman analysis showed wide limits of agreement (±59 mmHg systolic; ±49 mmHg diastolic pressure) between restraint and isoflurane measurements. DISCUSSION: Isoflurane caused more variability but there was agreement in BP evaluation by the isoflurane and restraint methods. Using the VPR system, light isoflurane-induced anesthesia and restraint could effectively be used to screen and quantify overt changes in hemodynamic parameters for cardiovascular research utilizing laboratory rodents.

Helminth-based therapies for rheumatoid arthritis: A systematic review and meta-analysis.

OBJECTIVE: Proteins from parasitic worms have been posed as novel therapies for rheumatoid arthritis (RA) and other auto-inflammatory diseases. However, with so many potential therapeutics, it is important that drug discovery be based on the specific phyla or species which show the most promising effects. Therefore, the aim of this systematic review and meta-analysis was to evaluate the reported effects of helminthic secretory proteins and derivative therapy on RA in an animal model. METHODS: Medline, Scopus and Web of Science were searched to identify studies evaluating helminthic therapy in the collagen-induced arthritis model of RA. A meta-analysis was undertaken to determine the overall effect of the proteins. Subgroup analyses were also undertaken to investigate individual treatments. RESULTS: Seven articles were included in the analysis. Overall, helminthic therapy significantly reduced arthritis score (SMD -1.193, 95% CI -1.525, -0.860). Subgroup analyses found a significant reduction in arthritis score following treatment with helminth protein ES-62 (SMD -1.186, 95% CI -1.633, -0.738) and phosphorylcholine-based treatment (SMD -0.997, 95% CI -1.423, -0.571). Subgroup analyses found ES-62 treatment significantly decreased IFN-γ levels (SMD -1.611, 95% CI -2.734, -0.487) and significantly increased levels of IL-10 (SMD 0.946, 95% CI 0.127, 1.765). CONCLUSIONS: Therapeutics from parasitic worms are a promising avenue for drug discovery, especially with all included studies reporting a significant improvement in arthritis score. Based on pooled data presented in this study, the nematode Acanthocheilonema viteae seems to be of particular interest for therapeutics.

A diet enriched with tree nuts reduces severity of atherosclerosis but not abdominal aneurysm in angiotensin II-infused apolipoprotein E deficient mice.

BACKGROUND AND AIMS: Diets enriched with tree nuts have been demonstrated to reduce the risk of atherosclerosis-related cardiovascular events. Abdominal aortic aneurysm (AAA) shares common risk factors with atherosclerosis and AAA patients commonly have atherosclerosis related cardiovascular events. AAA has some distinct pathological and clinical characteristics to those of atherosclerosis. No previous study has examined the effect of a diet enriched with tree nuts on experimental or clinical AAA. This study investigated the effect of a diet enriched with tree nuts on the development and severity of AAA within an experimental rodent model. METHODS: Male apolipoprotein E deficient mice were allocated to a diet enriched with tree nuts or control diet for 56 days (n = 17 per group). After 28 days, all mice were infused with angiotensin II whilst being maintained on their respective diets. The primary outcome was AAA severity assessed by the supra-renal aortic diameter, measured by ultrasound and ex vivo morphometric analysis. The severity of atherosclerosis was assessed by computer-aided analysis of Sudan IV stained aortic arches and sections of brachiocephalic arteries prepared with Van Gieson's stain. RESULTS: The diet enriched with tree nuts did not influence aortic diameter or aortic rupture incidence. Mice receiving the diet enriched with tree nuts had significantly less atherosclerosis within the brachiocephalic artery (p = 0.033) but not in the aortic arch. CONCLUSIONS: This experimental study suggests that a diet enriched with tree nuts does not reduce the severity of AAA, but does reduce the severity of atherosclerosis within the brachiocephalic artery. The study was not powered to identify a moderate effect of the diet on the primary outcome and therefore this cannot be excluded.

Flavonols reduce aortic atherosclerosis lesion area in apolipoprotein E deficient mice: A systematic review and meta-analysis.

Diets rich in flavonoids have been reported to have beneficial effects in the primary prevention of cardiovascular events. There are limited data, however, on the cardiovascular benefits of purified flavonoids. The aim of this systematic review and meta-analysis was to examine the reported effects of isolated flavonoids on aortic atherosclerosis in a mouse model. Medline, Pubmed, Science direct and Web of Science were searched to identify studies which examined the effect of isolated flavonoids on aortic atherosclerosis in apolipoprotein E deficient mice. A meta-analysis was performed to determine the overall effect of the flavonoids, and sub-analyses were performed to compare the effects of the flavonols and flavan-3-ols. Eleven studies, which examined a total of 208 mice receiving a flavonoid and 126 control mice, were included. Overall the flavonoids significantly reduced aortic atherosclerosis (SMD 1.10, 95% CI 0.69, 1.51). Of the 18 flavonoid interventions examined 12 were flavonols and 3 were flavan-3-ols. Sub-analyses suggested that the flavonols (SMD 1.31, 95% CI 0.66, 1.91) but not the flavan-3-ols (SMD 0.33, 95% CI -0.19, 0.85) significantly decreased atherosclerosis area. Of the eleven studies, only one examined histological markers of atherosclerosis plaque stability. Most studies did not report blinding of outcome assessors or reproducibility of the primary outcome, and did not justify the sample size used and flavonoid dose administered. Based on the included studies, the flavonols appear to be the most effective flavonoids for reducing aortic atherosclerotic lesion area in apolipoprotein E deficient mice.