The aim of our study was to determine the PPARγ agonism and hypoglycemic activity of natural phenolics isolated from Paulownia tomentosa and Morus alba. We started with a molecular docking preselection, followed by in vitro cell culture assays, such as PPARγ luciferase reporter gene assay and PPARγ protein expression by Western blot analysis. The ability of the selected compounds to induce GLUT4 translocation in cell culture and lower blood glucose levels in chicken embryos was also determined. Among the thirty-six plant phenolic compounds, moracin M showed the highest hypoglycemic effect in an in ovo experiment (7.33 ± 2.37%), followed by mulberrofuran Y (3.84 ± 1.34%) and diplacone (3.69 ± 1.37%). Neither moracin M nor mulberrofuran Y showed a clear effect on the enhancement of GLUT4 translocation or agonism on PPARγ, while diplacone succeeded in both (3.62 ± 0.16% and 2.4-fold ± 0.2, respectively). Thus, we believe that the compounds moracin M, mulberrofuran Y, and diplacone are suitable for further experiments to elucidate their mechanisms of action.

Center of Excellence Food Technology and Nutrition University of Applied Sciences Upper Austria 4600 Wels Austria

Department of Molecular Pharmacy Masaryk University 612 00 Brno Czech Republic

Department of Natural Drugs Masaryk University 612 00 Brno Czech Republic

Department of Pharmaceutical Sciences University of Vienna A 1090 Vienna Austria

FFoQSI GmbH Austrian Competence Centre for Feed and Food Quality Safety and Innovation 3430 Tulln Austria

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