Effects Of Potato On The Gut Microbiota And Metabolic Phenotype In Diet-induced Obese Mice

Obesity is a health issue that threatens the whole world,obese individuals are characterized by excessive fat accumulation with multiple symptoms including insulin resistance,hyperlipidemia and chronic systemic inflammation.The occurrence and development of obesity is closely related with gut microbiota.With a high nutritional value,potato components are proved beneficial to human health.Resistant starch,fiber,phenols and protein derived from potato can regulate glucose and lipid metabolism,thus,potato may contribute to the recovery from obesity.However,whether potato can modulate the gut microbiota,influence the obesity-related metabolic parameters and the relationship between gut microbiota and metabolic effects induced by potato remain unstudied.This study compared the effects of corn starch,raw potato flour and raw wheat flour on the metabolism and gut microbiota in diet-induced obese mice.Further,the effects of heat-treated potato flour on obesity phenotype and gut microbiota were investigated as well.First,we designed a dietary intervention on diet-induced obese mice with normal chow,raw potato diet and raw wheat diet respectively,monitored the obesity-associated metabolic parameters and analyzed the changes in the gut microbiota and correlate them with the parameters.After the seven-weeks' dietary intervention,mice fed with normal chow,raw potato diet and raw wheat diet exhibited 12.58%,27.08% and 16.45%weight loss,respectively.The weight of the visceral fat of mice fed with raw potato diet was significantly lower than those of the other groups,indicating that potato diet is beneficial for fat reduction.Moreover,raw potato reduced the systemic inflammation in mice.The caecal butyric acid and propionic acid of mice fed with raw potato diet were significantly higher than other groups,demonstrating that raw potato changed the microbial metabolites.Analysis of the sequencing data revealed that raw potato remarkedly decreased the ? diversity of the gut microbiota and changed the gut microbiota structure.Correlations among the 203 ASVs that occurred in more than 20% samples were calculated using Spar CC and ASVs were then clustered into 23 CAGs,20 of which were significantly correlated with the metabolic parameters of mice.CAGs 5 and 7,enriched by raw potato,were positively correlated with the recovery from obesity,most members from which were short chain fatty acids producing bacteria,including Bifidobacterium,Bacteroides,Faecalibacterium,Intestinimonas and Ruminiclostridium.Therefore,raw potato enriched the beneficial bacteria like SCFA-producing bacteria and thus contributed to the host health.Since the cooking process impacted the structure of potato starch and thus influenced the metabolic effects of potato,and potatoes were usually consumed after cooking,we also investigated the effects of processed potato on in obesity-related metabolism and gut microbiota structure in diet-induced mice.We conducted a seven-weeks' dietary intervention with the heat-treated potato diet in the diet-induced obese mice,measuring the glucose and lipid metabolic parameters,analyzing the gut microbiota changes and correlating these changes with metabolic parameters.The heat-treated potato intervention led to a 16.1% weight loss and liver,pancreas and adipose tissue weight loss.Glucose and lipid metabolism all exhibited recovery trend and no significant difference with the mice fed with normal chow diet.Analysis of the sequencing data indicated that potato intervention reduced the ? diversity of the gut microbiota and changed the gut microbiota structure.A total of 23 key ASVs responding to the potato intervention were selected by the Random Forest model,among which 6 were enriched by the heat-treated potato intervention and9 key ASVs were significantly correlated with the changes of metabolic parameters including body weight,fat mass,insulin.To conclude,raw potato enriched the SCFA-producing bacteria and improved the obesity phenotype,and they were obviously correlated.Moreover,heat-treated potato facilitated the recovery of glucose and lipid homeostasis in obese mice,which were significantly correlated with the modulation of the gut microbiota.Consequently,potato might become a good staple alternative in the future and functional foods made from potato could be envisioned to prevent obesity-related metabolic syndrome via the intervention of gut microbiota.