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Chronic inflammation exacerbates the cardiovascular complications of diabetes. Complement activation plays an important role in the inflammatory response and is known to be involved in ischemia-reperfusion (I/R) injury in the nondiabetic heart. The purpose of this study was to determine if increased complement deposition explains, in part, the increased severity of neutrophil-mediated I/R injury in the type 2 diabetic heart. Nondiabetic Zucker lean control (ZLC) and Zucker diabetic fatty (ZDF) rats underwent 30 min of coronary artery occlusion followed by 120 min of reperfusion. Another group of ZDF rats was treated with the complement inhibitor FUT-175 before reperfusion. Left ventricular (LV) tissue samples were stained for complement deposition and neutrophil accumulation following reperfusion. We found significantly more complement deposition in the ZDF LV compared with the ZLC (P < 0.05), and complement deposition was associated with significantly greater neutrophil accumulation. In whole blood samples taken preischemia and at 120 min reperfusion, neutrophils exhibited significantly more CD11b expression in the ZDF group compared with the ZLC group (P < 0.05). Furthermore, intracellular adhesion molecule (ICAM)-1 expression following I/R was increased significantly in ZDF hearts compared with ZLC hearts (P < 0.001). These results indicate that, in the ZDF heart, increased ICAM-1 and polymorphonuclear neutrophil (PMN) CD11b expression play a role in increasing PMN accumulation following I/R. The infarct size of the ZDF was significantly greater than ZLC (P < 0.05), and treatment with FUT-175 significantly decreased infarct size, complement deposition, and PMN accumulation in the diabetic heart. These findings indicate an exacerbated inflammatory response in the type 2 diabetic heart that contributes to the increased tissue injury observed following ischemia and reperfusion. myocardial ischemia-reperfusion; FUT-175; inflammation; neutrophil accumulation; CD11b/CD18

Abstract Background More than seventeen million Americans are afflicted with diabetes and these people have four times the rate of coronary heart disease (CHD) as non-diabetics. Furthermore, diabetic women have a 3.8 fold greater risk for CHD compared to diabetic men. Little is known why diabetic women are at an increased risk for CHD. It is possible that diabetic women with cardiovascular disease (CVD) have a greater inflammatory response resulting in an increased platelet neutrophil conjugate formation than diabetic men with CVD or non-diabetic women with CVD. This study tested the hypothesis that platelet-neutrophil conjugates, which are associated with several cardiovascular diseases, are increased in diabetic women with CVD compared to diabetic men with CVD and non-diabetic women with CVD. Methods Platelet-neutrophil conjugates were quantified by flow cytometry. The primary method is through direct binding of the neutrophil PSGL-1 receptor with P-selectin expressed on the platelet. Results In this study, we found when the blood was stimulated with PAF (platelet activating factor), diabetic women without CVD demonstrated an increase in platelet-neutrophil conjugates compared to diabetic women with CVD and non-diabetic women with CVD (% conjugates: 63.3 ± 5.2 vs 46.8 ± 4.3 vs 48.6 ± 3.4, p < 0.05). The stimulation ratio was significantly increased in diabetic and non-diabetic women with CVD in comparison to diabetic men with CVD (ratio: 3.3 ± 0.4 vs 3.3 ± 0.3 vs 2.1 ± 0.3, p < 0.05). Conclusion These results suggest that platelets and neutrophils in diabetic women have a greater potential for activation compared to diabetic men and may contribute to thrombosis/inflammation and the greater severity of coronary heart disease observed in diabetic women as compared to diabetic men.

Blood coagulation is the most significant complication of vascular biomaterials. A straightforward, sensitive, and standard measure of the compatibility of these materials with whole blood (hemocompatibility) is necessary to avoid coagulation. Current techniques used quantify only individual clotting components and are poor predictors of coagulation. The thromboelastograph (TEG) provides a measure of overall clot formation from whole blood. Although TEG is very common in clinical settings, its application to biomaterials is limited partly due to difficulty in sample preparation. In this protocol, whole blood samples are incubated with (1) biomaterials (tube with clamped ends) and (2) endothelial cells cultured on biomaterial surfaces (12-well plate) under controlled shearing conditions (10 rpm on rocker, at 37°C), and then the blood is transferred to the TEG to measure clot formation. TEG clearly discriminates among the R-times (time until initial clot formation) of expanded poly(tetrafluoroethylene), poly(urethane), and Tygon tubing. Marked differences in R-time are also seen when endothelial cells are cultured on various extracellular matrix proteins and proteoglycans. Thus, R-time provides a robust metric of overall thrombogenicity of biomaterials, and these procedures provide a standardized method for TEG to facilitate direct comparison among candidate biomaterials undergoing in-vitro testing. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012. [ABSTRACT FROM AUTHOR]

Aims: Neutrophil adhesion molecule CD11b and reactive oxygen species (ROS) are neutrophil activation markers for evaluating the functional activity of neutrophils. The aim of this study was to determine if neutrophils are activated in murine AIDS and/or chronic ethanol consumption and if neutrophil CD11b expression and ROS production vary when progressive retrovims infection occurs. Methods: Four groups were studied: control, murine AIDS, ethanol and ethanol plus murine AIDS. Neutrophil activation was assessed by CD11b expression and ROS production using flow cytometry. Results: We found that neutrophils lost their responsiveness to fMLP due to retrovirus or ethanol exposure. In the murine AIDS group, neutrophil CD11b expression was up-regulated along with a significant increase in ROS after 1 month of retroviral infection. After 2 months, neutrophil CD11b and ROS decreased. However, neutrophil CD11b expression further increased after 3 months. In the ethanol consumption group, neutrophil CD11b expression was down-regulated after 2 months, whereas ROS production increased in the first and third months. In the murine AIDS plus ethanol group, there were significant increases in both ROS and CD11b expression during the 3-month observation period. Conclusions: These findings suggest that neutrophil function is impaired by LP-BM5 retrovirus infection and/or chronic ethanol consumption. The pattern of neutrophil CD11b expression and ROS production might help to predict the stage of murine AIDS. Ethanol may further compromise neutrophil function in AIDS. [ABSTRACT FROM AUTHOR]

Background: More than seventeen million Americans are afflicted with diabetes and these people have four times the rate of coronary heart disease (CHD) as non-diabetics. Furthermore, diabetic women have a 3.8 fold greater risk for CHD compared to diabetic men. Little is known why diabetic women are at an increased risk for CHD. It is possible that diabetic women with cardiovascular disease (CVD) have a greater inflammatory response resulting in an increased platelet neutrophil conjugate formation than diabetic men with CVD or non-diabetic women with CVD. This study tested the hypothesis that platelet-neutrophil conjugates, which are associated with several cardiovascular diseases, are increased in diabetic women with CVD compared to diabetic men with CVD and non-diabetic women with CVD. Methods: Platelet-neutrophil conjugates were quantified by flow cytometry. The primary method is through direct binding of the neutrophil PSGL-1 receptor with P-selectin expressed on the platelet. Results: In this study, we found when the blood was stimulated with PAF (platelet activating factor), diabetic women without CVD demonstrated an increase in platelet-neutrophil conjugates compared to diabetic women with CVD and non-diabetic women with CVD (% conjugates: 63.3 ± 5.2 vs 46.8 ± 4.3 vs 48.6 ± 3.4, p < 0.05). The stimulation ratio was significantly increased in diabetic and non-diabetic women with CVD in comparison to diabetic men with CVD (ratio: 3.3 ± 0.4 vs 3.3 ± 0.3 vs 2.1 ± 0.3, p < 0.05). Conclusion: These results suggest that platelets and neutrophils in diabetic women have a greater potential for activation compared to diabetic men and may contribute to thrombosis/inflammation and the greater severity of coronary heart disease observed in diabetic women as compared to diabetic men. [ABSTRACT FROM AUTHOR]

Aims: Abnormal platelet counts have been noticed in acquired immune deficiency syndrome (AIDS) patients. However, the actual state of platelets in AIDS is unclear. We hypothesize that platelets are activated and platelet-derived microparticles increase in murine AIDS. Methods: To elucidate the ethanol effects on platelets in murine AIDS, we studied four groups: control, routine AIDS, ethanol, and ethanol plus murine AIDS. Platelet CD62p as a platelet activation marker and CD61[sup +] microparticles as platelet microparticles (PMPs) were measured by flow cytometry. Results: Platelets were significantly activated in mice with murine AIDS and chronic ethanol consumption. Increased platelet CD62p expression and increased PMPs were most pronounced in advanced stages of murine AIDS. Chronic ethanol consumption persistently enhanced platelet activation and PMP formation. Conclusions: Elevated platelet CD62p and PMPs may represent a pro-thrombotic status that have important pathological consequences. [ABSTRACT FROM AUTHOR]

Aims: The severity of cardiovascular complications in acquired immune deficiency syndrome (AIDS) patients may be associated with acute ischaemia-reperfusion injury. Epidemiological studies suggest that moderate ethanol consumption has myocardial protective effects. However, it is unknown if chronic ethanol consumption benefits acute myocardial ischaemia-reperfusion injury in AIDS. The aim of this study was to determine if chronic ethanol consumption modulates myocardial ischaemia-reperfusion injury in murine AIDS. Methods: Four groups were studied: control, murine AIDS, ethanol, and ethanol plus murine AIDS. All mice were subjected to 30 min of left anterior descending branch (LAD) occlusion and 120 min of reperfusion. Results: We found that the survival from an acute myocardial infarction was reduced in advanced-stage murine AIDS mice. Although early-stage murine AIDS hearts did survive in acute myocardial infarction, the infarct size was significantly larger. Chronic ethanol consumption significantly decreased infarct size compared to the control group. Chronic ethanol consumption also improved the survival of murine AIDS mice from an acute myocardial infarction. However, chronic ethanol consumption did not significantly reduce infarct size in murine AIDS. Conclusions: Our results indicate that multiple deleterious effects may enhance acute ischaemia-reperfusion injury in murine AIDS. The beneficial effects of chronic ethanol consumption in myocardial ischaemia-reperfusion injury may be due to modulation of neutrophil adhesion molecule expression and cytokine secretion. [ABSTRACT FROM AUTHOR]

— Background and Aims: The cardiovascular complications of AIDS are serious. However, the underlying mechanisms are unclear. Less is known about how ethanol affects the coronary microcirculation in individuals with AIDS. The aim of this study was to assess the integrity of the coronary microcirculation in murine AIDS mice in the presence or absence of chronic ethanol consumption. Methods: Four groups were studied: control, murine AIDS, ethanol and ethanol plus murine AIDS. Mouse hearts were prepared for direct visualization of the coronary microcirculation and quantification of trans-coronary macromolecular leakage. Hearts were isolated and perfused with diluted rat blood containing fluorescein isothiocyanate–albumin (FITC–BSA). Coronary vessels were observed using intravital fluorescence microscopy after 5, 15 and 25 min of perfusion. The mean luminosity of outside/inside coronary vessels (O/I ratio) was used to quantify FITC–BSA leakage. Results: We found that the mean O/I ratio for the murine AIDS group was significantly greater than in the control group and also significantly increased during the perfusion period. Chronic ethanol consumption did not alter coronary permeability to macromolecules, but improved the coronary haemodynamics in murine AIDS. Conclusions: These findings suggest that murine AIDS impairs the structural and functional coronary endothelium, and moderate ethanol consumption modulates the function of the coronary microcirculation. [ABSTRACT FROM PUBLISHER]

Cardiovascular complications account for the majority of morbidity and mortality among patients with diabetes. Myocardial infarctions are more severe in people with diabetes, and the mechanisms of this excess injury are not clearly understood. Glucagon-like peptide-1 (GLP-1) is an incretin with pleiotrophic effects, including glucose regulation and anti-apoptotic protection of some tissues, and is known to be deficient in type 2 diabetes. GLP-1 has been shown to decrease cardiac ischemia-reperfusion injury in rats in vivo when given as a preconditioning agent (prior to ischemia), and in isolated hearts when given as a preconditioning or postonditioning agent (immediately after ischemia). Due to the unpredictable nature of ischemic events in human heart disease, a low-risk agent that can confer cardioprotection when given during or immediately after ischemia would be an important therapeutic agent, and would provide a novel method of decreasing the burden of cardiovascular disease in diabetes. The aim of the present study was to determine if GLP-1, given during the reperfusion period after myocardial ischemia in vivo, decreases myocardial infarct size. Male Sprague-Dawley rats, 3 months of age (n = 5), were subjected to 30 minutes of ischemia followed by 120 minutes of reperfusion. The experimental protocol consisted of a window thoracotomy with occlusion of the left anterior descending coronary artery. Recombinant human GLP-1 (30 pmol/kg/min) was infused intravenously, beginning at the end of the occlusion period and continuing throughout reperfusion. Age-matched control animals (n = 4) were subjected to the same experimental protocol. The endpoint was the measurement of infarct size (stained with TTC) within the risk zone (stained with Trypan blue), expressed as a percentage of the area at risk (I/AAR%). Infarct size was significantly decreased (17% vs. 74% in controls, p< 0.05) in the animals treated with GLP-1 during reperfusion. These data suggest that treatment with GLP-1 can provide myocardial protection, even when given in vivo after the ischemic event. Further study is necessary to determine the mechanisms behind this protection, as well as the efficacy of myocardial postconditioning with GLP-1 in diabetic animals. [ABSTRACT FROM AUTHOR]

Diabetic patients have significantly more severe and fatal heart attacks than non-diabetic patients. In fact, cardiovascular disease is the leading cause of death among people with diabetes, accounting for two-thirds to three-fourths of all diabetes-related deaths. Inflammation may exacerbate ischemic heart disease, yet the mechanisms are not clear. Our lab has previously demonstrated that neutrophil trapping and sequestration in the microcirculation plays a significant role in ischemia/reperfusion (I/R) injury. The effects of neutrophil accumulation are not solely confined to mechanical plugging, the so-called "no-reflow" phenomenon. Neutrophils produce oxidants and pro-inflammatory cytokines that can enhance tissue injury. The purpose of this study was to determine if the severity of myocardial infarction in the type 2 diabetic heart is associated with neutrophil accumulation. Non-diabetic Zucker Lean Control (ZLC) and Zucker Diabetic Fatty (ZDF) rats underwent left anterior descending (LAD) coronary artery occlusion for 30min followed by 120min of reperfusion. Blood was sampled from the femoral artery pre-ischemia and incubated with a FITC-conjugated anti-CD11b antibody for detection of activated neutrophils using a FACSCaliber flow cytometer. At the end of reperfusion, cardiac tissue samples were freeze-fixed, sectioned, and stained for neutrophils using Napthol ASD Chloroacetate Esterase. There was significantly greater CD11b expression on ZDF neutrophils compared to their lean controls (ZLC: 9.3 ± 1.1 TFI, ZDF: 17.1 ± 1.9 TFI; p < 0.05), suggesting that neutrophils from diabetic blood are in a "primed" state. Indeed, there was significantly greater neutrophil accumulation in the post-ischemic left ventricle of the ZDF compared to the ZLC (ZLC: 53.0 ± 9.4; ZDF: 96.8 ± 16.4; p < 0.05). These results parallel infarct size measurements in which the infarct-to-AAR percentage of the ZDF was significantly greater than control (ZLC: 25.7% I/AAR; ZDF: 56.9% I/AAR; p < 0.05). These findings indicate that increased neutrophil accumulation in the left ventricle of the ZDF heart following I/R may result from pre-activation of diabetic neutrophils and may contribute to the increased myocardial injury observed in type 2 diabetes. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated an association of particulate matter (PM) exposure and cardiovascular (CV) complications. However, the mechanisms of PM-induced CV complications are not clear. Because coarse PM is often associated with lipopolysaccharide (LPS), we investigated if coarse PM (≤10 µm mean aerodynamic diameter) combined with LPS would induce pulmonary and systemic inflammation. C57BL/6J mice were intratracheally instilled with 100µl of saline, PM (200µg), LPS (100µg), or PM+LPS. Eighteen hours later, pulmonary and systemic inflammation were assessed by the measurement of proinflammatory cytokines TNF-α and IL-6 in lung homogenate and plasma, We found that pulmonary TNF-α and IL-6 were significantly different among the PM, LPS, and PM+LPS groups, where the latter group had the greatest concentration. There were no differences in plasma TNF-α among the groups. However, plasma IL-6 was significantly greater in the PM+LPS group, but not in the LPS group, compared to the PM group. Our results demonstrate that the PM+LPS group elicited the greatest response in pulmonary and systemic inflammation. These findings indicate that the combination of coarse PM and LPS causes a systemic inflammatory response which may aggravate the CV complications of air pollution. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, unexpected activity patterns emerged among Yucatan mini-swine models for heart failure and atrial fibrillation. As part of our laboratory research, we tracked activity data by FitBark™ collars that the Yucatan mini-swine wore. Previously, staff engaged with the swine daily, such as applying lotion and conducting 6-min treadmill runs. However, pandemic restrictions reduced interaction to 1 or 2 times a week, often for less than 10 min each session. Contrary to expectations, there was a significant increase in the swine's activity levels during these minimal interaction periods. After cleaning, moisturizing, weighing, and FitBark data collection, staff engaged with the swine through feeding and play. Three time frames were analyzed: prepandemic, pandemic, and reentry. Prepandemic and reentry periods involved daily 15-min interactions with 2 staff members per swine to maintain cleanliness and health. During the pandemic, interaction was reduced to 1 or 2 times weekly. The hours between 1000 and 1400 were designated as 'passive activity', representing the swines' isolated behavior, unaffected by staff interaction. The chronic heart failure swine ( n = 3) had an average passive activity area under the curve prepandemic value of 47.23 ± 2.52 compared with pandemic 57.09 ± 2.90, pandemic 57.09 ± 2.90 compared with reentry 50.44 ± 1.61, and prepandemic compared with reentry. The atrial fibrillation swine ( n = 3) had an average passive activity area under the curve minimal interaction (mimicking pandemic) value of 59.27 ± 6.67 compared with interaction (mimicking prepandemic or reentry) 37.63 ± 1.74. The heightened activity levels during minimal interaction suggest physiologic and psychologic changes in the animals due to reduced socialization. This highlights the importance of enrichment and interaction in research animals and underscores the broader impact of the COVID-19 pandemic on research outcomes. These findings could also shed light on the effects of the pandemic on human behavior.

Aims: Neutrophil adhesion molecule CD11b and reactive oxygen species (ROS) are neutrophil activation markers for evaluating the functional activity of neutrophils. The aim of this study was to determine if neutrophils are activated in murine AIDS and/or chronic ethanol consumption and if neutrophil CD11b expression and ROS production vary when progressive retrovirus infection occurs., Methods: Four groups were studied: control, murine AIDS, ethanol and ethanol plus murine AIDS. Neutrophil activation was assessed by CD11b expression and ROS production using flow cytometry., Results: We found that neutrophils lost their responsiveness to fMLP due to retrovirus or ethanol exposure. In the murine AIDS group, neutrophil CD11b expression was up-regulated along with a significant increase in ROS after 1 month of retroviral infection. After 2 months, neutrophil CD11b and ROS decreased. However, neutrophil CD11b expression further increased after 3 months. In the ethanol consumption group, neutrophil CD11b expression was down-regulated after 2 months, whereas ROS production increased in the first and third months. In the murine AIDS plus ethanol group, there were significant increases in both ROS and CD11b expression during the 3-month observation period., Conclusions: These findings suggest that neutrophil function is impaired by LP-BM5 retrovirus infection and/or chronic ethanol consumption. The pattern of neutrophil CD11b expression and ROS production might help to predict the stage of murine AIDS. Ethanol may further compromise neutrophil function in AIDS.