Effects Of Parabacteroides Distasonis From Macaca Fascicularis On Hyperlipidemia

Hyperlipidemia(HLP)is a key risk factor for cardiovascular disease(CVD),and its incidence is increasing year by year.High sugar and high fat(HSHF)diet is one of the important leading causes of HLP.The role of gut microbiota in HLP is gradually being recognized.Howerver,by far,the majority of HLP-related animal model research has been conducted in rodent models.Given the dramatical differences in genetic background and gut microbiota composition between rodents and primates including humans,in contrast,non-human primate(NHP)models provide a unique tool to understand the relationship between HLP and gut microbiota.In the current study,HLP models were induced in Macaca fascicularis and mice by an HSHF diet.In this study,the adult male Macaca fascicularis were divided into an HSHF diet-induced group(HSHF group,N=7)and a normal diet group(Control group,N=6).The Macaca fascicularis in the HSHF group were fed an HSHF diet for 7 months.The peripheral blood of Macaca fascicularis was collected to detect the levels of serum lipids and fatty acids(FA)in the 0th(before induction)and 7th months of the dietary intervention.The results showed that total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C)and FA in the serum of Macaca fascicularis increased significantly,indicating that the HSHF diet-induced the HLP of Macaca fascicularis.Transcriptome sequencing of peripheral blood leukocytes of Macaca fascicularis showed that the innate immunity and inflammatory pathways of HLP Macaca fascicularis were significantly up-regulated,indicating that HSHF diet induced immune-inflammatory responses in Macaca fascicularis.The feces of Macaca fascicularis were collected for metagenomic sequencing.The results showed that the gut microbiota of HLP Macaca fascicularis was significantly different from normal Macaca fascicularis.Abundances bacteria negatively correlated with TC and LDL-C such as Lactobacillus johnsonii,Lactobacillus reuteri and Lactobacillus mucosae were significantly decreased,While abundances of bacteria positively correlated with TC and LDL-C such as Bacteroides unifomis,Alistipes senegalw,and especially Parabacteroides distasonis(P.distasonis)were significantly increased in the gut microbiota of HLP Macaca fascicularis.In order to further verify the effect of gut microbiota on HLP,C57BL/6J mice were fed the HSHF diet for 8weeks to induce HLP.The levels of TC and LDL-C in the plasma were significantly increased in HSHF diet-induced HLP mice.To verify the effect of changes in the gut microbiota of Macaca fascicularis on the HLP of host,fecal microbiota of HLP Macaca fascicularis was collected and transplanted into HSHF diet-induced HLP mice.Blood lipids profiles and inflammatory markers in mice were measured.The results showed that transplantation of fecal microbiota(FMT)from HLP Macaca fascicularis aggravated dyslipidemia and inflammatory response in HLP mice by increasing levels of TC,LDL-C,Tnf-α and LPS in the plasma.16 S r RNA gene high-throughput sequencing of mouse cecal contents showed that FMT aggravated the gut microbiota dysbiosis in HLP mice,mainly including increased abundance of potentially harmful bacteria such as Fusobacterium and Bacteroides,and decreased abundance of potentially beneficial bacteria such as Eubacterium,Akkermansia and Lactobacillus.Notably,the abundance of P.distasonis in the gut microbiota of HLP Macaca fascicularis and HLP mice was significantly increased and correlated with blood lipid levels.In order to further verify the effect of P.distasonis on HLP development,P.distasonis was isolated from the fecal sample from HLP Macaca fascicularis and mono-innoculated into HSHF diet-induced HLP mice.Blood lipids analysis showed that the mono-innoculation of P.distasonis increased the plasma TC and LDL-C levels in HLP mice.16 S r RNA gene high-throughput sequencing showed that the mono-innoculation of P.distasonis increased the abundance of potentially harmful bacteria such as Oscillibacter and Alistipe in cecal microbiota.To study the effect of P.distasonis on the metabolome of mouse cecum and plasma,metabolomic analysis of mouse plasma and cecal contents was conducted using gas chromatography-mass spectrometry(GC-MS).The metabolomic results showed that lysophosphatidylcholine(LPC)and phosphatidylcholine(PC)were two major common differential metabolites shared by the plasma and cecal content.In general,the following three conclusions can be drawn in this study:(1)HSHF diet-induced HLP in Macaca fascicularis,was accompanied by up-regulated inflammatory and innate immune pathways in peripheral blood leukocytes and gut microbiota dysbiosis.(2)Fecal microbiota transplantation from HLP Macaca fascicularis to mice further aggravated dyslipidemia,inflammatory response and gut microbiota in the HLP mice.(3)Mono-innoculation of P.distasonis also aggravated dyslipidemia and gut microbiota dysbiosis in HLP mice,and contribute to the development of HLP by changing the lipid metabolite profiles of the host’s gut and blood,and increasing the production of PC and LPC.