Abstract 179: Targeted Inhibition of Plasminogen Activator Inhibitor-1 Attenuates Weight Gain and Prevents Vascular Dysfunction Following a High Fat Diet

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Sadiya S Khan ◽  
Alexander Mackie ◽  
Lauren Beussink-Nelson ◽  
Christine E Kamide ◽  
Anne S Henkel ◽  
...  

Introduction: Elevated plasminogen activator inhibitor-1 (PAI-1) is associated with obesity, but there is controversy whether PAI-1 causes or is a consequence of obesity. We sought to determine whether targeted PAI-1 inhibition with a novel small molecule antagonist (TM5441) alters the development of obesity and/or obesity-induced vascular dysfunction in a diet-induced obesity model. Methods and Results: C57BL/6J mice were fed control, high fat diet (HFD), or high fat diet with TM5441 (HFD+TM5441) for 12 weeks. The HFD had marked weight gain (77±5%) as compared with control (32±2%). TM5441 significantly attenuated weight gain (49±8%, p=0.0075, Figure). HFD-induced hepatic triglyceride accumulation was attenuated by TM5441 (116±31 vs. 76±35 mg trig/g liver, p=0.03). Energy expenditure was reduced in the HFD compared to control (11.1±0.4 vs. 12.9±0.4 kcal/h/kg, p=0.005). However, HFD+TM5441 maintained a level of energy expenditure that was similar to control (13.2±0.6 kcal/h/kg, p=NS). The HFD group demonstrated higher systolic and diastolic blood pressure (141±3; 112±3 mm Hg) compared with control (122±7, 94±8; P<0.05 for both), while administration of TM5441 prevented diet-associated increase (120±6; 93±7 mm Hg, p=NS compared to control) at week 12. Pressure myography of mesenteric arteries in the HFD showed a significant rightward shift in the constrictor response to phenylephrine as compared to control (EC50: 14.5uM vs. 25.1uM, p=0.002). The HFD+TM5441 was similar to control (p=NS). Conclusions: Inhibition of PAI-1 with TM5441 attenuates weight gain, enhances energy expenditure, and prevents obesity-related vascular dysfunction in a murine model of obesity.

PPAR Research ◽  
2009 ◽  
Vol 2009 ◽  
pp. 1-13 ◽  
Author(s):  
Jennifer C. Carter ◽  
Frank C. Church

Breast cancer is the most prominent cancer among females in the United States. There are a number of risk factors associated with development of breast cancer, including consumption of a high-fat diet and obesity. Plasminogen activator inhibitor-1 (PAI-1) is a cytokine upregulated in obesity whose expression is correlated with a poor prognosis in breast cancer. As a key mediator of adipogenesis and regulator of adipokine production, peroxisome proliferator-activated receptor-γ(PPAR-γ) is involved in PAI-1 expression from adipose tissue. We summarize the current knowledge linking PPAR-γand PAI-1 expression to high-fat diet and obesity in the risk of breast cancer.


2005 ◽  
Vol 93 (05) ◽  
pp. 816-819 ◽  
Author(s):  
Roger Lijnen

SummaryPlasminogen activator inhibitor-1 (PAI-1) is the main physiological inhibitor of tissue-type (t-PA) and urokinase-type (u-PA) plasminogen activator. Recent studies in murine models have yielded apparently conflicting data on a potential role of PAI-1 in adipose tissue development and obesity. To reinvestigate this issue, we have rederived PAI-1 deficient (PAI-1-/-) and wild-type (WT) mice and generated true littermates in a 81.25% C57Bl/6: 18.75% 129 SV genetic background. Male 5-week-old PAI-1-/- and WT mice were kept on a high fat diet (20.1 kJ/g) for 15 weeks. Body weight gain was comparable for both genotypes, and at the time of sacrifice total body weights (39 ± 1.1 versus 41 ± 1.2 g) as well as the weights of subcutaneous (SC, 1,520 ± 110 versus 1,480 ± 110 mg) adipose tissue were not significantly different. In contrast, the gonadal (GON, 1,900 ± 43 versus 1,510 ± 86 mg, p < 0.005) tissue mass was larger in PAI-1-/- mice. Plasma levels of insulin, leptin, glucose, triglycerides, total, HDL and LDL cholesterol were comparable for both genotypes. Immunohisto-chemical analysis of SC and GON adipose tissues did not reveal differences in adipocyte size or number between both genotypes, whereas blood vessel density was also comparable for GON fat but lower in SC fat of WT mice. Thus, this study in littermate mice on high fat diet did not reveal an effect of PAI-1 deficiency on body weight, and a differential effect on SC and GON adipose tissue.


2008 ◽  
Vol 283 (20) ◽  
pp. 13538-13548 ◽  
Author(s):  
Charmi Shah ◽  
Guang Yang ◽  
Ian Lee ◽  
Jacek Bielawski ◽  
Yusuf A. Hannun ◽  
...  

2005 ◽  
Vol 173 (4S) ◽  
pp. 255-255 ◽  
Author(s):  
Hugo H. Davila ◽  
Thomas R. Magee ◽  
Freddy Zuniga ◽  
Jacob Rajfer ◽  
Nestor F. GonzalezCadavid

1999 ◽  
Vol 82 (07) ◽  
pp. 104-108 ◽  
Author(s):  
Franck Paganelli ◽  
Marie Christine Alessi ◽  
Pierre Morange ◽  
Jean Michel Maixent ◽  
Samuel Lévy ◽  
...  

Summary Background: Type 1 plasminogen activator inhibitor (PAI-1) is considered to be risk factor for acute myocardial infarction (AMI). A rebound of circulating PAI-1 has been reported after rt-PA administration. We investigated the relationships between PAI-1 levels before and after thrombolytic therapy with streptokinase (SK) as compared to rt-PA and the patency of infarct-related arteries. Methods and Results: Fifty five consecutive patients with acute MI were randomized to strep-tokinase or rt-PA. The plasma PAI-1 levels were studied before and serially within 24 h after thrombolytic administration. Vessel patency was assessed by an angiogram at 5 ± 1days. The PAI-1 levels increased significantly with both rt-PA and SK as shown by the levels obtained from a control group of 10 patients treated with coronary angioplasty alone. However, the area under the PAI-1 curve was significantly higher with SK than with rt-PA (p <0.01) and the plasma PAI-1 levels peaked later with SK than with rt-PA (18 h versus 3 h respectively). Conversely to PAI-1 levels on admission, the PAI-1 levels after thrombolysis were related to vessel patency. Plasma PAI-1 levels 6 and 18 h after SK therapy and the area under the PAI-1 curve were significantly higher in patients with occluded arteries (p <0.002, p <0.04 and p <0.05 respectively).The same tendency was observed in the t-PA group without reaching significance. Conclusions: This study showed that the PAI-1 level increase is more pronounced after SK treatment than after t-PA treatment. There is a relationship between increased PAI-1 levels after thrombolytic therapy and poor patency. Therapeutic approaches aimed at quenching PAI-1 activity after thrombolysis might be of interest to improve the efficacy of thrombolytic therapy for acute myocardial infarction.


1988 ◽  
Vol 59 (02) ◽  
pp. 299-303 ◽  
Author(s):  
Grazia Nicoloso ◽  
Jacques Hauert ◽  
Egbert K O Kruithof ◽  
Guy Van Melle ◽  
Fedor Bachmann

SummaryWe analyzed fibrinolytic parameters in 20 healthy men and 20 healthy women, aged from 25 to 59, before and after 10 and 20 min venous occlusion. The 10 min post-occlusion fibrinolytic activity measured directly in diluted unfractionated plasma by a highly sensitive 125I-fibrin plate assay correlated well with the activity of euglobulins determined by the classical fibrin plate assay (r = 0.729), but pre-stasis activities determined with these two methods did not correlate (r = 0.084). The enhancement of fibrinolytic activity after venous occlusion was mainly due to an increase of t-PA in the occluded vessels (4-fold increase t-PA antigen after 10 min and 8-fold after 20 min venous occlusion). Plasminogen activator inhibitor (PAI) activity and plasminogen activator inhibitor 1 (PAI-1)1 antigen levels at rest showed considerable dispersion ranging from 1.9 to 12.4 U/ml, respectively 6.9 to 77 ng/ml. A significant increase of PAI-1 antigen levels was observed after 10 and 20 min venous occlusion. At rest no correlation was found between PAI activity or PAI-1 antigen levels and the fibrinolytic activity measured by 125I-FPA. However, a high level of PAI-1 at rest was associated with a high prestasis antigen level of t-PA and a low fibrinolytic response after 10 min of venous stasis. Since the fibrinolytic response inversely correlated with PAI activity at rest, we conclude that its degree depends mainly on the presence of free PAI.


1992 ◽  
Vol 68 (05) ◽  
pp. 486-494 ◽  
Author(s):  
Malou Philips ◽  
Anne-Grethe Juul ◽  
Johan Selmer ◽  
Bent Lind ◽  
Sixtus Thorsen

SummaryA new assay for functional plasminogen activator inhibitor 1 (PAI-1) in plasma was developed. The assay is based on the quantitative conversion of PAI-1 to urokinase-type plasminogen activator (u-PA)-PAI-l complex the concentration of which is then determined by an ELISA employing monoclonal anti-PAI-1 as catching antibody and monoclonal anti-u-PA as detecting antibody. The assay exhibits high sensitivity, specificity, accuracy, and precision. The level of functional PAI-1, tissue-type plasminogen activator (t-PA) activity and t-PA-PAI-1 complex was measured in normal subjects and in patients with venous thromboembolism in a silent phase. Blood collection procedures and calibration of the respective assays were rigorously standardized. It was found that the patients had a decreased fibrinolytic capacity. This could be ascribed to high plasma levels of PAI-1. The release of t-PA during venous occlusion of an arm for 10 min expressed as the increase in t-PA + t-PA-PAI-1 complex exhibited great variation and no significant difference could be demonstrated between the patients with a thrombotic tendency and the normal subjects.


Sign in / Sign up

Export Citation Format

Share Document