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Published on: July 21, 2017
Inhibition of PAI-1 Promotes Lipolysis and Enhances Weight Loss in Obese Mice
Joshua A Levine1, Shantel Olivares1,2, Toshio Miyata3
1Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
Objective:
This study investigates the therapeutic potential of a small molecule inhibitor of plasminogen activator inhibitor-1 (PAI-1), TM5441, in reversing diet-induced obesity in mice.
Methods:
Wild-type C57BL/6J mice were fed a high-fat high-sugar (HFHS) diet for 8 weeks to induce obesity. After the first 8 weeks, TM5441 was added to the diet for an additional 8 weeks. In order to determine the efficacy of PAI-1 inhibition in conjunction with dietary modification, mice were fed an HFHS diet for 8 weeks to induce obesity and were then switched to a low-fat diet with or without TM5441 for an additional 2 to 8 weeks.
Results:
Obese mice showed weight reduction and significant improvement in hepatic steatosis when TM5441 was added to the HFHS diet. Obese mice that were treated with TM5441 in conjunction with dietary modification showed enhanced weight loss and a more rapid reversal of hepatic steatosis compared with obese mice treated with dietary modification alone. The enhanced weight loss among mice treated with TM5441 was associated with increased adipose tissue expression of adipose triglyceride lipase, phosphorylated hormone-sensitive lipase, and phosphorylated perilipin-1 as well as induction of adipose tissue lipolysis.
Conclusions:
Pharmacologic PAI-1 inhibition stimulates adipose tissue lipolysis and enhances weight loss in obese mice.
Insights
A novel inhibitor of plasminogen activator inhibitor-1 (PAI-1), TM5441, effectively reduced weight and improved liver health in obese mice. This small molecule enhances adipose tissue lipolysis, offering a new therapeutic avenue for obesity treatment.
Area of Science:
- Metabolic research
- Pharmacology
- Obesity studies
Background:
- Diet-induced obesity is a growing health concern.
- Plasminogen activator inhibitor-1 (PAI-1) plays a role in metabolic dysfunction.
- Small molecule inhibitors offer targeted therapeutic potential.
Purpose of the Study:
- To investigate the therapeutic efficacy of TM5441, a PAI-1 inhibitor, in reversing diet-induced obesity in mice.
- To assess the impact of TM5441 on weight reduction and hepatic steatosis.
- To explore the mechanisms underlying TM5441's effects on adipose tissue.
Main Methods:
- Obesity was induced in C57BL/6J mice using a high-fat high-sugar (HFHS) diet for 8 weeks.
- TM5441 was administered orally via diet for an additional 8 weeks, either with the HFHS diet or a low-fat diet.
- Key indicators of weight, hepatic steatosis, and adipose tissue lipolysis were measured.
Main Results:
- TM5441 treatment led to significant weight reduction and improved hepatic steatosis in obese mice.
- Combined TM5441 and dietary modification resulted in enhanced weight loss and faster reversal of hepatic steatosis.
- Weight loss was associated with increased adipose triglyceride lipase and enhanced adipose tissue lipolysis.
Conclusions:
- Pharmacologic inhibition of PAI-1 with TM5441 stimulates adipose tissue lipolysis.
- TM5441 effectively enhances weight loss in obese mouse models.
- This study highlights PAI-1 inhibition as a promising strategy for obesity management.
