Potato extract (Potein) suppresses food intake in rats through inhibition of luminal trypsin activity and direct stimulation of cholecystokinin secretion from enteroendocrine cells

J Agric Food Chem. 2011 Sep 14;59(17):9491-6. doi: 10.1021/jf200988f. Epub 2011 Aug 16.

Abstract

Dietary proteins and trypsin inhibitors are known to stimulate the secretion of the satiety hormone cholecystokinin (CCK). A potato extract (Potein) contains 60% carbohydrate and 20% protein including trypsin inhibitory proteins. In this study, we examined whether Potein suppresses food intake in rats and whether it directly stimulates CCK secretion in enteroendocrine cells. In fasted rats, food consumption was measured up to 6 h after the oral administration of Potein or soybean trypsin inhibitor (SBTI). CCK-releasing activities of Potein and SBTI were examined in the murine CCK-producing cell line STC-1. Potein inhibited the trypsin activity in vitro with a potency 20-fold lower than that of SBTI. Oral administration of Potein dose-dependently suppressed food intake for 1-6 h. Potein, but not the SBTI, dose-dependently induced CCK secretion in STC-1 cells. These results suggest that Potein suppresses food intake through the CCK secretion induced by direct stimulation on enteroendocrine cells and through inhibition of luminal trypsin.

MeSH terms

  • Animals
  • Cell Line
  • Cholecystokinin / metabolism*
  • Eating / drug effects*
  • Enteroendocrine Cells / drug effects*
  • Enteroendocrine Cells / metabolism
  • Male
  • Plant Extracts / pharmacology
  • Plant Proteins / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Satiation / drug effects
  • Solanum tuberosum / chemistry*
  • Trypsin Inhibitors / pharmacology*

Substances

  • Plant Extracts
  • Plant Proteins
  • Trypsin Inhibitors
  • Cholecystokinin