Diets Containing Egg or Whey Protein and Inulin Fiber Improve Energy Balance and Modulate Gut Microbiota in Exercising Obese Rats

Abstract

Scope: Dietary protein, prebiotic fiber, and exercise individually have been shown to aid in weight loss; however less is known of their combined effects on energy balance. The effects of diets high in protein and fiber, with exercise, on energy balance, hormones, and gut microbiota, were determined. Methods and Results: Obese male rats were fed high-fat diets with high protein and fiber contents from egg protein and cellulose, egg protein and inulin, whey protein and cellulose, or whey protein and inulin, together with treadmill exercise. We found that inulin enriched diets decreased energy intake and respiratory quotient (RQ), increased energy expenditure (EE), and upregulated transcripts for cholecystokinin (CCK), peptide YY, and proglucagon in distal gut. Notably, CCK1-receptor blockade attenuated the hypophagic effects of diets and in particular whey-inulin diet, and 𝜷-adrenergic blockade reduced EE across all diets. Egg-cellulose, egg-inulin, and whey-inulin diets decreased weight gain, adiposity, and hepatic lipidosis; decreased lipogenic transcripts, improved glycemic control, and upregulated hepatic glucose metabolism transcripts; and decreased plasma insulin and leptin. Importantly, diet was linked to altered gut microbial composition and plasma metabolomics, and a subset of predicted metagenome pathways and plasma metabolites significantly correlated, with plasma butyric acid the most strongly associated to metagenome function. Conclusion: Combination of dietary egg or whey protein with inulin and exercise improved energy balance, glucose metabolism, upregulated anorectic hormones, and selectively modulated gut microbiota and plasma metabolites.

Dietary approaches for normalizing dysbiosis induced by high-fat, obesogenic diets

“…This experiment then evaluated the additional beneficial effects dietary fiber could have in exercising rats. The results showed that both inulin-containing diets decreased food intake and weight gain and improved glycemic control more so than cellulose-containing diets, and this was similar to previous work in nonexercised rats [47 ▪ ]. Diet type explained 46% of the total variation in cecal microbiota composition, and plasma butyric acid, a short-chain fatty acid, was the plasma metabolite that was most strongly associated with the predicted functional pathways identified from metagenomic sequencing [47 ▪ ].…”

“…Several studies have been investigating inulin, a soluble fiber, as a potential dietary supplement to alleviate the sequelae of high fat diets and obesity. A combination of egg or whey protein with either cellulose (insoluble fiber) or inulin (soluble fiber) was evaluated for improving weight gain and obesity-associated metabolic alterations in in obese rats fed high fat diets and exercised on a treadmill [47 ▪ ]. This experiment then evaluated the additional beneficial effects dietary fiber could have in exercising rats.…”

Potential Benefits of Egg White Proteins and Their Derived Peptides in the Regulation of the Intestinal Barrier and Gut Microbiota: A Comprehensive Review

“…Feeding 750 mg/kg of EWP hydrolysate to obese rats significantly reduced the relative abundance of Lactobacillus and decreased lactate content . When obese rats were fed insulin and EWP together, the SCFA level in their bodies also increased . Feeding ovotransferrin-derived peptides IRW and IQW to obese mice decreased F/B values but did not affect the relative abundance of Actinobacteriota, Proteobacterota, and Deferribacterota …”

“…129 When obese rats were fed insulin and EWP together, the SCFA level in their bodies also increased. 130 Feeding ovotransferrin-derived peptides IRW and IQW to obese mice decreased F/B values but did not…”

Cross-Talk Between Gut Microbiota and Adipose Tissues in Obesity and Related Metabolic Diseases

“…A growing body of evidence suggests that the gut microbiota is a bridge to connect the external environment and the host homeostasis. On the one hand, the composition of gut microbiota can be affected by region (20), race/ethnicity (21), diet (22)(23)(24), and host genetics (6). For example, geographical location has been suggested to be closely associated with gut microbiota variation (20), and race/ethnicity (22) or its correlates such as diet and socioeconomic status have important influences on gut microbiota.…”