Effects Of Chenpi On Obesity And Gut Microbiota In Mice Fed With High Fat Diet

Chenpi is a kind of dried citrus peel from Citrus reticulata.It is rich in flavonoids and volatile oil.It is a medicinal material with the same origin of medicine and food.It is often used to treat dyspepsia and respiratory inflammation.In recent years,researchs on the effect of chenpi on weight loss and lipid-lowering were increasing.Through 16S rRNA high-throughput sequencing and non targeted metabolomics technology,this study discussed the physiological and biochemical effects of chenpi on obese mice fed with high-fat diet from three perspectives:chenpi composition,chenpi feeding form and the storage years of chenpi,discussed the relationship between chenpi composition and year in the effect of chenpi on weight loss and lipid reduction,and elaborated the relationshiP between gut microbiota and the effect on weight loss and lipid reduction.Firstly,the composition differences and changes of volatile oil and flavonoids of chenpi in different years(3,5 and 10 years)were measured.Then different forms of chenpi(chenpi powder and chenpi decoction)were used to feed mice,and effects on fat accumulation,antioxidant capacity,gut microbiota and short chain fatty acids(SCFAs)were observed to determine which form of chenpi feeding can have better effect on weight loss and lipid reduction.Then,the high-fat obese mice model was established.Taking the normal diet as the control and chenpi as the positive group.Chenpi in different years was added to the diet.After 13 weeks of feeding,the weight,food intake,relative weight of adipose tissues and liver,serum biochemical indexes,anti-inflammatory and antioxidant indexes were recorded.Histopathological observation and other methods were used to study the different inhibitory effects of chenpi on lipid deposition and obesity in obese mice in different years,and 16S rRNA high-throughput sequencing technology was used to analyze the effect of chenpi on intestinal flora in mice,so as to explore the relationship between intestinal microorganisms and lipid-lowering effect of chenpi.The main conclusions are as follows:(1)The results of solid phase microextraction combined with gas chromatography-mass spectrometry and metabolomics showed that the main volatile oil components of chenpi were D-limonene,anthranilic acid and carvacrol.Thymol,phenol and(-)-spathulenol are unique to chenpi for ten years.Substances such as D-limonene,anthranilic acid,p-cymene andy-terpinene decreased gradually with the increase of years.Carvacrol、α-Farnesene and α-Terpineol and other substances increased first and then decreased with the increase of storage year.There were significant differences in flavonoids in three groups of chenpi in different years.The contents of naringin and isolimonin increased with the increase of chenpi years.The content of quercetin decreased first and then increased,and the content of limonin increased first and then decreased.Metabonomics shows that there are great differences in metabolites between groups.KEGG metabolic pathway analysis shows that the biosynthesis pathway of secondary metabolites is the most enriched pathway involved in the differential metabolites of chenpi,and the biosynthesis of flavonoids and amino acids are also the main pathways.The volatile oil and flavonoids contained in chenpi will change with time,so there are differences in the effects of weight loss and lipid reduction.(2)Chenpi powder can significantly reduce the weight of abdominal adipose tissue,subcutaneous adipose tissue and the level of serum triglyceride(TG).At a deeper level,chenpi powder significantly increased the proportion of Bacteroidetes and Firmicutes,and increased the abundance of Muribaculaceae and Muribaculum in the intestinal microbiota,but it was not significant.The contents of acetic acid,valeric acid and butyric acid in chenpi powder grouP increased slightly,but there was not significant.Chenpi decoction can reduce perirenal adipose tissue and has good antioxidant activity,but has little effect on intestinal flora.The decoction of chenpi had no significant effect on the content of SCFAs.The results showed that chenpi powder was better than chenpi decoction in weight loss and lipid reduction.(3)Chenpi can effectively reduce white fat deposition,increase brown adipose tissue,and reduce the content of serum TG in obese mice.After chenpi treatment,the content of high-density lipoprotein increased significantly,low-density lipoprotein(LDL)、total cholesterol(TC)and triglyceride decreased significantly.The levels of serum TC and LDL in chenpi grouP decreased most significantly in the TEN-group.The antioxidant effect of chenpi in different years was different,and the antioxidant effect of chenpi in three years was better.With the increase of time,chenpi showed better anti-inflammatory and anti obesity effects.Chenpi can reduce the level of serum inflammatory factor IL-1β、IL-6、TNFa and lipopolysaccharide(LPS)content.Chenpi can change the abundance and composition of intestinal flora in obese mice.It can increase the ratio of Bacteroidetes to Firmicutes and the abundance of Allobaculum and Muribaculaceae.The effect of reducing fat and reducing weight of chenpi is related to its year.Compared with three-year chenpi,five-year and ten-year chenpi has better effect on inhibiting fat deposition and regulating intestinal microorganisms.This study found that chenpi can effectively regulate the imbalance of gut microbiota caused by high-fat diet to achieve its role in weight loss and lipid reduction,and can also play the role of anti-oxidation and anti-inflammatory to improve the bad impacts of obesity.Chenpi in the longer the aging age has better the effect of chenpi on weight loss and lipid reduction,but the antioxidant performance has little to do with the age of chenpi,which provides a basis for the application of chenpi as a weight loss food in the food industry.