Dietary delivery of glycomacropeptide within the whey protein matrix is not effective in mitigating tissue ceramide deposition and obesity in high fat fed mice

• Published in: Journal of dairy science 2023-09, Vol.107 (2), p.669-682
• Main Authors: de Hart, Naomi M M P, Petrocelli, Jonathan J, Nicholson, Rebekah J, Yee, Elena M, van Onselen, Lisha, Lang, Marisa J, Bourrant, Paul-Emile, Ferrara, Patrick J, Bastian, Eric D, Ward, Loren S, Petersen, Brent L, Drummond, Micah J
• Format: Article
• Language: English
• ISSN: 1525-3198; 0022-0302; 1525-3198
• DOI: 10.3168/jds.2023-23914

Obesity is often accompanied by heightened circulating and tissue inflammation along with an increase in sphingolipids (e.g., ceramides) in metabolically active and insulin-sensitive organs. Whey protein isolate (WPI) has been shown to decrease inflammation and increase insulin sensitivity when given during a high-fat diet (HFD) intervention in rodents. The whey protein bioactive peptide glycomacropeptide (GMP) has also been linked to having anti-inflammatory properties and regulating lipogenesis. Therefore, the purpose of the study was to determine the effect of dietary GMP within the whey protein matrix on tissue inflammation, adiposity, and tissue ceramide accumulation in an obesogenic rodent model. Young adult male mice (10 weeks old) underwent a 10-wk 60% HFD intervention. GMP was absent in the control low-fat diet and HFD WPI (-GMP) groups. HFD WPI (1xGMP) contained a standard amount of GMP while HFD WPI (2xGMP) had double the amount. We observed no differences in weight gain or reductions in adiposity when comparing the GMP groups to HFD WPI (-GMP). Similarly, insulin resistance and glucose intolerance were not offset with GMP, and skeletal muscle and liver tissue ceramide content was unaltered with the GMP intervention. In contrast, the additional amount of GMP (2xGMP) might adversely affect tissue obesity-related pathologies. Together, dietary GMP given in a whey protein matrix during a HFD intervention does not alter weight gain, insulin resistance, glucose intolerance, and sphingolipid accumulation in the liver and skeletal muscle.Obesity is often accompanied by heightened circulating and tissue inflammation along with an increase in sphingolipids (e.g., ceramides) in metabolically active and insulin-sensitive organs. Whey protein isolate (WPI) has been shown to decrease inflammation and increase insulin sensitivity when given during a high-fat diet (HFD) intervention in rodents. The whey protein bioactive peptide glycomacropeptide (GMP) has also been linked to having anti-inflammatory properties and regulating lipogenesis. Therefore, the purpose of the study was to determine the effect of dietary GMP within the whey protein matrix on tissue inflammation, adiposity, and tissue ceramide accumulation in an obesogenic rodent model. Young adult male mice (10 weeks old) underwent a 10-wk 60% HFD intervention. GMP was absent in the control low-fat diet and HFD WPI (-GMP) groups. HFD WPI (1xGMP) contained a standard amount of GMP while HFD WPI (2xGMP)