pai-039 and Body-Weight

The effect of a novel small molecule plasminogen activator inhibitor (PAI-1) inhibitor on adipose tissue physiology was investigated.. In human preadipocyte cultures, PAI-039 inhibited both basal and glucose-stimulated increases in active PAI-1 antigen, yet had no effect on PAI-1 mRNA, suggesting a direct inactivation of PAI-1. Differentiation of human preadipocytes to adipocytes was associated with leptin synthesis, which was significantly reduced in the presence of PAI-039, together with an atypical adipocyte morphology characterized by a reduction in the size and number of lipid containing vesicles. In a model of diet-induced obesity, pair-fed C57 Bl/6 mice administered PAI-039 in a high-fat diet exhibited a dose-dependent reduction in body weight, epididymal adipose tissue weight, adipocyte volume, and circulating plasma active PAI-1. Plasma glucose, triglycerides, and leptin were also significantly reduced in drug-treated mice, and concentrations of PAI-039 associated with these physiological effects were near the in vitro IC50 for the inhibition of PAI-1.. Our results indicate that a small molecule inactivator of PAI-1 can neutralize glucose-stimulated increases in PAI-1 in human preadipocyte cultures, reduce adipocyte differentiation, and prevent the development of diet-induced obesity. These data suggest the pharmacological inhibition of PAI-1 could be beneficial in diseases associated with expansion of adipose tissue mass.

Topics: Acetates; Adipocytes; Adipose Tissue; Adult; Animals; Body Weight; Cell Count; Cell Differentiation; Cells, Cultured; Female; Glucose; Humans; Indoleacetic Acids; Indoles; Mice; Mice, Inbred C57BL; Organ Size; Plasminogen Activator Inhibitor 1; Stem Cells

To investigate the effect of tiplaxtinin, designed as a synthetic inhibitor of plasminogen activator inhibitor-1 (PAI-1), on obesity, male C57Bl/6 mice (13-14 weeks old) were kept on a high-fat diet (20.1 kJ/g) for four weeks without or with addition of tiplaxtinin (PAI-039) at a dose of 2 mg/g food. At the time of sacrifice, body weights were significantly lower in the inhibitor-treated mice (p < 0.0005). The weights of the isolated subcutaneous and gonadal fat deposits were also significantly lower (both p < 0.0005), associated with adipocyte hypotrophy. Inhibitor-treated adipose tissues displayed similar blood vessel size, but a higher blood vessel density. Fasting glucose and insulin levels, as well as glucose-tolerance tests were not significantly affected by the inhibitor treatment, whereas plasma triglyceride levels were significantly reduced (p = 0.02) and LDL-cholesterol levels significantly enhanced (p = 0.0002). Insulin-tolerance tests revealed significantly lower glucose levels at the end of the test in the inhibitor treated mice (p = 0.03). Thus, in this model of diet-induced obesity in mice administration of tiplaxtinin resulted in impaired adipose tissue development.

Topics: Adipose Tissue; Animals; Anti-Obesity Agents; Blood Glucose; Body Weight; Dietary Fats; Disease Models, Animal; Energy Intake; Fibrinolysis; Glucose Tolerance Test; Indoleacetic Acids; Insulin; Lipids; Male; Mice; Mice, Inbred C57BL; Neovascularization, Pathologic; Obesity; Organ Size; Plasminogen Activator Inhibitor 1; Time Factors

To investigate the role of plasminogen activator inhibitor-1 (PAI-1) in adipose tissue development and insulin metabolism.. Aged male wild-type (WT) or transgenic mice with adipose tissue overexpression of PAI-1 (45-55 weeks) in 50% C57Bl/6: 50% Friend Virus B-strain (FVB) genetic background, kept on normal chow, were used without or with administration of a synthetic low molecular weight PAI-1 inhibitor (PAI-039) to the food (1 mg g(-1)) for 4 weeks.. The PAI-1 transgenic mice showed somewhat lower body weight and adipose tissue mass than WT mice, whereas fasting insulin levels were higher. Glucose and insulin tolerance tests did not reveal significant differences between both genotypes. Addition of PAI-039 to the food did not significantly affect total body fat, weight of the isolated s.c. and gonadal fat territories or their adipocyte size and blood vessel composition in either genotype. Fasting glucose levels and glucose tolerance tests were, for both genotypes, comparable with those without inhibitor treatment. Insulin levels and insulin tolerance tests in WT, but not in PAI-1 transgenic mice, suggested a higher insulin sensitivity after inhibitor treatment (insulin level 30 min after glucose injection of 2.0 +/- 0.17 ng mL(-1) vs. 3.2 +/- 0.48 ng mL(-1) without inhibitor treatment; P = 0.028).. In this model, overexpression of PAI-1 moderately impaired adipose tissue formation without affecting glucose or insulin tolerance. Administration of a synthetic PAI-1 inhibitor for 4 weeks did not affect adipose tissue development in WT or PAI-1 transgenic mice, but induced a higher insulin sensitivity in WT mice.

Topics: Acetates; Adipose Tissue; Animals; Body Composition; Body Weight; Indoleacetic Acids; Indoles; Insulin; Insulin Resistance; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Plasminogen Activator Inhibitor 1