Effects of whey protein concentrate and hydrolyzed whey/egg protein blends on post‐prandial markers of adipose tissue lipolysis in rats (LB440)

We examined how gavage‐feeding the following dietary proteins (10 human eq. g dissolved in 1 ml of water) acutely affected omental (OMAT) and inguinal/subcutaneous (SQ) adipose tissue lipolysis markers: a) 80% whey protein concentrate (WPC, n = 15); b) 70% hydrolyzed whey + 30% hydrolyzed egg albumin (70W/30E, n = 15); c) 50W/50E (n = 15); d) 30W/70E (n = 15); and e) 1 ml of water with no protein (fasted, n = 14). 70W/30W feeding increased SQ fat phosphorylated hormone‐sensitive lipase (p‐HSL) 3.1‐fold compared to fasting and 1.9‐4.4‐fold compared to all other test proteins 180 min post feeding (p < 0.05). WPC, 70W/30E and 50W/50E feedings increased OMAT p‐HSL 3.8‐6.5‐fold 180 min post‐feeding compared to fasted rats (p < 0.05). WPC and 70W/30E feedings depressed serum free fatty acids 90 min post‐feeding compared to fasting and other test proteins (p < 0.05), but this was normalized by 180 min post‐feeding. Interestingly, 70W/30E and 50W/50E feedings tended to increase SQ fat PGC1‐α mRNA 180 min post‐feeding compared to fasting rats (2.3‐2.4‐fold, p < 0.10), and 50W/50E significantly increased Ucp3 mRNA 180 min post‐feeding compared to all other test proteins as well as fasting (~2.0 fold, p < 0.05). In summary, despite a transient 90‐min post feeding depression in serum FFAs with 70W/30E feeding, solutions with 50% and 70% hydrolyzed whey increased select tissue markers of lipolysis and thermogenesis 180 min post‐feeding. Source of Research Support: 4LIFE Research, Inc.