Glyceollins, one of the phytoalexins derived from soybeans under fungal stress, enhance insulin sensitivity and exert insulinotropic actions.
Glyceollins are a category of phytoalexins that are produced by soybeans under fungal stress, but their effects on glucose homeostasis remain unknown. We hypothesized that glyceollins play an important role in glucose homeostasis by regulating glucose utilization in adipocytes and improving beta-cell function and survival. Glyceollins improved insulin-stimulated glucose uptake in 3T3-L1 adipocytes without activating the peroxisome proliferator-activated receptor-gamma agonist. They decreased triacylglycerol accumulation in adipocytes. In addition, glyceollins slightly improved glucose-stimulated insulin secretion without palmitate treatment in Min6 cells, and they potentiated insulinotropic actions when 500 microM palmitate was used to induce beta-cell dysfunction. This was associated with decreased beta-cell apoptosis because of the attenuation of endoplasmic reticulum stress, as determined by mRNA levels of XBP-1, ATF-4, ATF-6, and CHOP. Glyceollins also potentiated GLP-1 secretion to enhance insulinotropic actions in enteroendocrine cells. In conclusion, glyceollins help normalize glucose homeostasis by potentiating beta-cell function and survival and improving glucose utilization in adipocytes.
Park
Sunmin
S
Department of Food and Nutrition, Obesity/Diabetes Center, College of Science, Natural Hoseo University, Asan 336-795, Korea. smpark@hoseo.edu
Ahn
Il Sung
IS
Kim
Jeong Hwan
JH
Lee
Mee Ryung
MR
Kim
Jong Sang
JS
Kim
Hyo Jung
HJ
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D005947:Glucose / Q000378:metabolism; D007328:Insulin / Q000378:metabolism*; D050417:Insulin-Secreting Cells / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D010936:Plant Extracts / Q000494:pharmacology*; D036343:Pterocarpans / Q000494:pharmacology*; D012233:Rhizopus / Q000502:physiology; D013025:Glycine max / Q000737:chemistry* / Q000382:microbiology*
D007328:Insulin; D010936:Plant Extracts; D036343:Pterocarpans; C017343:glyceollin; D005947:Glucose