Blood collection and analysis
For plasma glucose measurements, blood samples were collected in tubes containing sodium fluoride-EDTA (Venoject 2, Terumo Corporation, Tokyo, Japan) and stored at 4 °C for later analysis. For plasma insulin, total PYY, and glycerol measurements, venous blood samples were collected in dipotassium salt-EDTA tubes (Venoject 2, Terumo Corporation, Tokyo, Japan) and were centrifuged immediately at 1861 