A new agonist for peroxisome proliferation-activated receptor γ (PPARγ), fraglide-1 from zhenjiang fragrant vinegar: Screening and characterization based on cell culture experiments

Abstract

Zhenjiang fragrant vinegar (Kozu) is a black rice vinegar that has been used as a traditional Chinese medicine and has various health benefits, including anti-obesity effects. In the present study, using luciferase reporter assays of PPARγ promoter activity, a novel ingredient from 8-year-old Kozu, 5-hydroxy-4-phenyl-butenolide, was isolated. The newly found agonist was named as “Fraglide-1”. Moreover, in subsequent experiments, it was confirmed that fraglide-1 was an PPARγ agonist and it could increase expression level of the uncoupling protein (UCP)-1. Fraglide-1 was chemically synthesized and it was verified that expression of the PPARγ was increased in dose dependent manner. Although Kozu has been consumed globally as a functional food for thousands of years, the mechanisms behind its health effects have not been characterized. The active ingredient of Kozu was successfully found and the results unraveled a longtime mystery about Kozu for its beneficial health effect.