1-trifluoromethoxyphenyl-3(1-propionylpiperidin-4-yl) urea (TPPU), a soluble epoxide hydrolase inhibitor attenuates high fat diet-induced cardiovascular and metabolic disorders in rats

OBJECTIVE: Obesity was induced in rats by feeding on a high fat diet (HFD), 60% w/w cholesterol, 20% w/w carbohydrates, and 20% w/w proteins for two months. MATERIALS AND METHODS: Animals were fed on a HFD and treated concurrently with a single daily dose of vehicle or TPPU (2 mg/kg p.o) for two months. Body weights, blood pressure, and biochemical investigations of all animals were registered at 0, 1, and 2 months of the experimental period. RESULTS: Vehicle-treated rats fed on a HFD had a considerable increase in body weight compared to age-matched control animals fed on a regular diet (regular diet; 311.40 +/- 9.60 vs. HFD; 446 +/- 12.67). The body weight of rats fed on a HFD and concurrently treated with 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4yl) urea (TPPU; 2 mg/kg p.o) daily for two months was significantly decreased (p<0.01). A significant (p<0.01) increase in the systolic blood pressure of animals and vascular dysfunction with blunted relaxant response to acetylcholine and sodium nitroprusside was evident in vehicle-treated animals fed on a HFD compared to control rats fed on a regular diet. These HFD-induced disorders were markedly attenuated in animals fed on a HFD and treated concurrently with a single daily dose of TPPU (2 mg/kg p.o). HFD diet-induced deleterious metabolic changes were prevented with concurrent administration of TPPU (2 mg/kg p.o). TPPU treatment decreased the HDF-induced increase in plasma creatinine levels (p<0.001) in rats. The adiponectin levels were decreased (p<0.001) in vehicle-treated rats fed on HFD for two months compared to control rats fed on a normal diet ( p<0.001). Adiponectin levels were significantly (p<0.001) increased in rats fed on HFD and treated concurrently with TPPU (2 mg/ kg p.o). HFD diet caused a marked increase in plasma leptin levels of animals which were significantly decreased in animals fed on a HFD and treated concurrently with TPPU for two months. Obese animals exhibited increased levels of plasma insulin compared to control animals fed on a regular diet which were significantly suppressed (p<0.001) by TPPU treatment. In the current investigation, TPPU treatment had a favorable impact on the levels of other metabolic parameters such as plasma cholesterol, triglycerides (TGs), low density lipoproteins (LDLs), and high density lipoproteins (HDL). HFD caused a profound increase in the serum liver enzymes, the effect was reversed by treatment of animals with TPPU (2 mg/kg p.o). CONCLUSIONS: The findings of our current study indicate the promising therapeutic potential of TPPU as a new drug candidate to manage obesity-induced cardiovascular and metabolic disorders. Soluble epoxide hydrolase inhibitors such as TPPU could prevent HFD-induced obesity and related cardiovascular and metabolic complications.