Attenuating effect of casein glycomacropeptide on proliferation, differentiation, and lipid accumulation of in vitro Sprague-Dawley rat preadipocytes

Abstract

Food components with the ability to suppress preadipocyte proliferation and intracellular lipid accumulation may be helpful in the prevention of obesity, which is a worldwide health concern. Casein glycomacropeptide (GMP), which has pronounced gastric inhibitory activity, could potentially possess fat synthesis inhibition properties and an obesity-alleviating capacity. The objective of the present study was to investigate the effect of GMP on the proliferation and differentiation of preadipocytes as well as triglyceride accumulation and glycerol-3-phosphate dehydrogenase activity in preadipocytes isolated from Sprague-Dawley rats. Different dosages (0, 0.31, 0.625, 1.25, 2.5, and 5.0 mg/mL) of GMP were co-incubated with preadipocytes. The proliferation activity of preadipocytes significantly decreased in the GMP-treated group compared with that of the control group without GMP supplementation. The GMP exhibited an inhibitory effect against preadipocyte proliferation in a dose-dependent manner; the maximal antiproliferative effect was obtained with 2.5 mg/mL. The GMP also attenuated differentiation, as revealed by decreased lipid content, and the effect was more pronounced when cells were treated with GMP before or at the beginning of differentiation induction than at later stages of cell differentiation. Cultured preadipocytes treated with GMP accumulated fewer triglycerides and had lower glycerol-3-phosphate dehydrogenase activity than did the control cells without GMP supplementation. In conclusion, GMP can inhibit the proliferation, differentiation, and lipid accumulation of preadipocytes in vitro.

Whey Peptides Stimulate Differentiation and Lipid Metabolism in Adipocytes and Ameliorate Lipotoxicity-Induced Insulin Resistance in Muscle Cells

“…Previous studies showed mixed effects of milk peptides on PPARγ activation. Peptides from casein glycomacropeptides or tuna fish decreased PPARγ protein levels and lipid accumulation in primary rat and 3T3-L1 preadipocytes, respectively [42,43]. Conversely, Chakrabarti and Wu [18] showed that synthetic lactotripeptides, IPP and VPP, originally resulting from casein digestion during fermentation, upregulate PPARγ levels and lipid storage in 3T3-F442A cells.…”

Endotoxin-Binding Peptides Derived from Casein Glycomacropeptide Inhibit Lipopolysaccharide-Stimulated Inflammatory Responses via Blockade of NF-κB activation in macrophages

“…Casein glycomacropeptide (GMP), which is a casein-derived whey peptide, deserves much interest for its proposed biological activities, such as inhibiting intestinal bacterial adhesion and inhibition from binding of cholera toxin (CT) to Chinese hamster ovary (CHO)-K1 cells [ 19 , 20 ]. Our previous studies have demonstrated that GMP supplementation efficiently suppresses the proliferation, differentiation and lipid accumulation of in vitro pre-adipocytes [ 21 ]. GMP can also reduce plasma total cholesterol and slightly ameliorate the inflammatory state in obese rats [ 22 ].…”

Casein glycomacropeptide‐derived peptide IPPKKNQDKTE ameliorates high glucose‐induced insulin resistance in HepG2 cells via activation of AMPK signaling

“…Glycomacropeptide (GMP), a κ‐casein‐derived macropeptide f(106–169) comprised of 64 amino acids, has been reported to possess many bioactivities, such as reducing weight gain, decreasing cardiovascular disease risk markers, and improving intestinal flora . In our previous study, GMP reduces body weight of obese Sprague‐Dawley (SD) rats induced by high‐fat diet, and inhibits proliferation and differentiation of preadipocytes isolated from SD rats in vitro . Furthermore, our study shows that papain‐generated peptides from GMP suppress lipopolysaccharide‐induced inflammatory response in murine RAW 264.7 macrophages, and protect macrophages from hydrogen peroxide‐induced oxidative stress .…”