A Comparative Study Of Intestinal Flora And Its Metabolites Short-chain Fatty Acid And Injury Markers Of Intestinal Mucosal In HIV-infected And Healthy Subjects

Objective: AIDS is a common sexually transmitted disease,the HIV virus infection can cause serious deficiency of cellular immune,lead to a variety of opportunistic infections and is seriously harm to human health.Under normal circumstances,there is a symbiotic relationship between the body and the microorganism,intestinal microflora and metabolites play an important role in the digestion and absorption of nutrients to maintain the normal physiologic function of the intestine,regulating immune and other vital life activities.Most of the patients with AIDS will appear chronic diarrhea,abdominal pain and other gastrointestinal symptoms.Studies have shown that it may be associated with intestinal mucosal injury,intestinal flora translocation,intestinal micro-ecological imbalance and other pathological mechanisms,but specific mechanism is not clear.In this study,we select HIV patients who have not yet developed to AIDS,and observe their intestinal microecology and intestinal mucosal injury,and explore whether their intestinal microecology is related to intestinal mucosal injury and cellular immune status.We will focus on the following aspects of the study 1.Compare intestinal flora and its important metabolites short-chain fatty acids of HIV infection and healthy control group;2.Compare injury markers of Intestinal mucosal of HIV infection and healthy control group;3.analyze whether intestinal flora ?short-chain fatty acids and injury markers of intestinal mucosal have the correlations;4.analyze whether intestinal flora?short-chain fatty acids and CD4 +,CD8 + T cell,CD4 / CD8 ratio of HIV patients have the correlations.Through this experiment,we can improve the mechanism of intestinal mucosal injury caused by HIV infection and get good measures that intestinal microecology-related treatments are used to cure the AIDS patients.Methods: Fifteen cases of HIV patients from the Infectious Diseases Hospital and 10 cases of healthy persons were selected.All the subjects were given informed consent before the experiment.The experiment was agreed by the Sichuan Provincial People's Hospital Ethics Committee.The collected stool specimens were saved in-80 ?deep freezer.The differences of intestinal flora between the two groups were analyzed by high-throughput sequencing;and the differences of short chain fatty acid between the two groups were analyzed by gas chromatography-mass spectrometry(GC-MS).The concentration of I-FABP and D-lactate of blood samples between the two groups were analyzed by enzyme-linked immunosorbent assay(ELISA);and the amount of CD4 +,CD8 + T cells and CD4 / CD8 ratio of HIV patients were measured by flow cytometry(FUM).Finally,we use Mann-Whitney test,t test analysis of SPSS19.0 statistical software to analyze the differences of bacterial species or OTUs;and use the Person method to analyze the correlation,(P <0.05 suggest differences were statistically significant).Result: 1.Results of intestinal flora: Compared with the healthy control group,there were no significant differences at the level of Phylum,for example:Bacteroidetes?Firmicutes?Proteobacter ?Fusobacteria?Actinobacteria.At the level of Class,Negativicutes was significantly increased.At the level of Family,Rikenellaceae and Microbacteriaceae were significantly decreased,and Moraxellaceae was significantly increased.At the level of Genus,Roseburia?Lachnospiraceae?Alistipes?Ruminococcaceae were significantly decreased;Psychrobacter was significantly increased.2.Short-chain fatty acid quantitative results: Compared with the healthy control group,butyric acid and valeric acid were significantly reduced in HIV infection group.3.Injury markers of Intestinal mucosal: Compared with the healthy control group,the concentration of injury markers I-FABP and D-lactic of intestinal mucosal have no significant difference.4.Cellular immunity: the count of CD4 + T cells in HIV-infected patients were greater than 200 / ?L,CD8 + T cells were increased,and CD4 / CD8 ratio were decreased,which was consistent with the cellular immune status of HIV infected patients.5.The correlation between intestinal microflora and butyric acid and valeric acid: At the level of the Family,the concentration of butyric acid was positively correlated with Rikenellaceae and Ruminococcaceae.The concentration of valeric acid was positively correlated with Rikenellaceae,Peptococcaceae and Ruminococcaceae.At the level of the Genus,the concentration of butyric acid was positively correlated with the Alistipes,Roseburia,Blautia,Lachnospiraceae UCG-005,Lachnospiraceae FCS020 group,Ruminococcaceae UCG-003,Ruminococcus 1.The concentration of valeric acid is positively correlated with the Alistipes,Eubacterium coprostanoligenes group,Ruminococcaceae UCG-002,Ruminococcaceae UCG-003,Ruminococcaceae NK4A214 group,Ruminococcaceae 1,Eubacterium ruminantium group,Peptococcus.6.The correlation between CD4 +,CD8 + T cells,CD4 / CD8 ratio and intestinal flora : No intestinal flora was correlated with CD4 + T cells.CD8 + T cells were positively correlated with:Oxalobacer,Undibacterium,Burkholderia,Achromobacter,Ramlibacter,Proteobacteria,Sphingobacteria.7.The correlation between short-chain fatty acids and CD4 +,CD8 + T cells,CD4 / CD8 ratios :CD4 + T cells,CD4 / CD8 ratio were negatively correlated with acetic acid,CD8 + T cells were positively correlated with valeric acid.Conclusion: 1.Although HIV-infected patients have not developed to AIDS,important protected factors of their intestinal tract have been reduced,damaged factors have been increased.Changes in intestinal microecology indicate that the intestinal health will gradually developed to impaired state,which is related with the significant decrease of Roseburia ?Lachnospiraceae ? Alistipes ? Ruminococcaceae ? Rikenellaceae and increase of Psychrobacter ?Moraxellaceae.2.The increase of Moraxellaceae and Psychrobacter in the intestinal tract suggest that it may be closely related to the microbia translocation and lead to sustained inflammatory response and worse the development of HIV infection.3.The amount of T lymphocytes in HIV-infected patients who have not yet developed to AIDS are not associated with intestinal microflora.4.The relationship between short-chain fatty acids in HIV infection patients and cellular immune need to continued research.