Whey protein and soy protein prevent obesity by upregulating uncoupling protein 1 to activate brown adipose tissue and promote white adipose tissue browning in high-fat diet-fed mice

Abstract

There are inconsistent conclusions regarding the effect of whey protein and soy protein supplementation on obesity, and the underlying mechanisms of a high-protein diet for weight loss remain to be...

Soy protein compared with whey protein ameliorates insulin resistance by regulating lipid metabolism, AMPK/mTOR pathway and gut microbiota in high-fat diet-fed mice

“…The ingredients of the experimental diets have been reported in our previous study. 14 After feeding for 12 weeks, all mice were fasted for 12 hours and anesthetized with 3% sodium pentobarbital via intraperitoneal injection, and blood was obtained through enucleating the eyeball. Then, the mice were sacrificed by cervical dislocation.…”

“…Our previous study reported the result of the ITT, indicating that SPI could better improve insulin sensitivity relative to WPI. 14 Effect of WPI and SPI on weight of the liver and gastrocnemius muscle Macroscopic observation indicated that the livers of the SPI groups were more bright red in color compared with the WPI groups (Fig. 1A).…”

“…HOMA-IR = FBG (mmol L −1 ) × FINS (μIU mL −1 )/22.5; HOMA-IS = 1/HOMA-IR. 14,28 Histopathology Fresh liver tissues obtained from the same site of the liver were quickly put into 4% paraformaldehyde for 24 hours at room temperature, and then these fixed liver tissues were embedded and sectioned (thickness 6 μm). These sections were stained with Oil Red O and hematoxylin and eosin (H&E).…”

“…5 AMPK is a central regulator of energy homeostasis, and its activation can upregulate the IRS-1/PI3K/AKT signaling pathway. 14,18 mTOR is considered to be a sensor of ambient amino acid concentration, and S6 kinase 1 (S6K1) is its downstream target. 46 It is well known that BCAAs can activate mTOR and S6K1.…”

“…12 In addition, our previous study found that whey protein could prevent obesity better compared with soy protein, while whey protein supplementation significantly elevated the areas under the curve (AUC) of the insulin tolerance test (ITT) and serum concentrations of ALT and AST compared with soy protein, indicating that the anti-obesity effect of whey protein might be independent of its anti-insulin resistance (IR) effect. 14 Thus, the impact of whey protein and soy protein on IR needs to be further investigated.…”