Glucometabolic Response to Walnut (Juglans regia L.) Supplementation During Gestation and/or Lactation in Offspring of Sprague-Dawley Rats

Background and Objective: Walnut (WN) (Juglans regia L.) has been reported to be the most widely planted tree nut worldwide. It is consistently referred to as the white WN, Persian WN, common WN or English WN. This study explored the impact of WN (Juglans regia L.) supplementation during gestation and/or lactation on glucose equilibrium in offspring of dams. Materials and Methods: Eighteen pregnant female and 12 male Sprague-Dawley rats were used in this study and fed either a basic diet or WN supplementation (WS). The gestating rats were exposed to WS up to parturition (gestational WN supplementation, GWS), or from parturition to day 21 after birth (lactation WN supplementation, LWS) or for a term covering both (GL WN supplementation, WN). At day 63 after birth, a blood specimen was collected for assay of fasting glucometabolic parameters. Results: Fasting serum glucose (FSG), fasting serum insulin (FSI) and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) p<0.05 remarkably reduced in GWS and GLWS with a noticeable increase p<0.05 in LWS matched with control. Skeletal glycogen content noticeable increase of p<0.05 in GWS and a noticeable downturn in LWS and GLWS p<0.05 while hepatic glycogen content showed a noticeable downturn p<0.05 in GWS and LWS matched with CONT. Intestinal and pancreatic alpha-amylase and alpha-glucosidase produced a remarkably reduced p<0.05 in GWS, LWS and GLWS matched with CONT. Conclusion: The exposure to a walnut-enriched diet during pregnancy and/or lactation improved glucose metabolism, as reflected in reduced insulin resistance and down-regulation of alpha-amylase and alpha-glucosidase.