Study On The Interaction Of Intestinal Microflora And Inflammatory Cytokines In Drug Na?ve First Episode Schizophrenia Patients

Objectives1.To investigate the changes of intestinal microflora in drug na?ve first episode schizophrenia patients, and explore the possible role of intestinal microflora proportion on the pathogenesis of schizophrenia.2. To observe the changes of cytokines in drug na?ve first episode schizophrenia patients, and understand the immune status of schizophrenia.3. To analyze the relevance of the intestinal microflora and inflammatory cytokines, serum glucose and lipid metabolism, and further investigate possible mechanisms of intestinal microflora in the pathogenesis of schizophrenia. Methods1. From December in 2013 to October in 2014, 36 experimenters were recruited from the department of psychiatry of the First Affiliated Hospital of Zhengzhou University and 30 healthy control subjects were enrolled in the study. All patients enrolled were obtained detailed history, physical examination and psychiatric examination, and were collected clinical data, and were assessed by Positive and Negative Symptoms Scale(PANSS), and were measured the height, weight, counting body mass index(BMI).2. Serum glucose levels were measured by glucose oxidase method; serum cholesterol, triglyceride, high density lipoprotein and low density lipoprotein levels were measured by enzymatic colorimetric assay; cytokines IL-1β, IL-6, TNF-α levels were determined by enzyme linked immunosorbent assay(ELISA).3. Extraction of total DNA from fecal bacteria: DNAs were extracted according to the QIAamp stool mini kit instructions, and DNA concentrations were measured by ultraviolet spectrophotometer.4. To analyze the absolute quantification of fecal Bifidobacterium, Lactobacillus, and Bacteroides by the method of real-time fluorescent quantitative PCR: according to the 16 Sr RNA gene sequences, design the species specific primers, amply the routine PCR and purify and recycle PCR products, construct standard plasmid. Applying SYBR Green I fluorescent dye, analyze the gradient dilution of the standards and samples, establish standard curve, and analyze the absolute quantification of fecal Bifidobacterium, Lactobacillus, and Bacteroides.5. The statistical software SPSS 19.0 was used to analyze experimental data. Normal distribution of measurement data were tested using the Kolmogorov-Smirnov single sample. The values were presented with mean and standard deviation. The two groups’ parameters were compared using Independent- Samples T Test. If they do not obey the normal distribution, the data were presented with the median. The two groups’ parameters were compared using non parametric Mann-Whitney U test. Correlations between the intestinal bacteria and glucose, lipid metabolism and inflammatory factors were analyzed by Pearson correlation analysis when the data fit the normal distribution; while using Spearman correlation analysis when do not meet the normal distribution. Count data were compared by using chi-square test. The bilateral P<0.05 were considered statistically significant. Results1. There were no significant differences between case group and control group in age, education level, gender and smoking history(P >0.05).2. There were no significant differences in the two groups in BMI, blood glucose, cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein(P >0.05).3. Serum IL-1β, IL-6, TNF-α levels in schizophrenia patients(52.89±13.75、33.47±14.04、46.61±17.74) ng/L were significantly higher than those in healthy control subjects(22.42±10.97、14.87±6.45、28.70±13.33) ng/L(P <0.05).4. The numbers of fecal Bifidobacterium in schizophrenia patients(6.97±0.75) lg copies/g wet fecals were lower than those in healthy control subjects(7.87±0.68) lg copies/g wet fecals(P<0.001); the contents of Lactobacillus had no statistical significance(P=0.131);the numbers of fecal Bacteroides in schizophrenia patients(8.72±1.32) lg copies/g wet fecals were higher than those in healthy control subjects(7.53±1.62)lg copies/g wet fecals(P<0.05); the intestinal Lactobacillus/Bacteroides ratio in case group(1.01 + 0.21) was less than that of control group(1.24 + 0.33)(P<0.05); and the intestinal Bifidobacterium/ Bacteroides ratio(0.82 + 0.17) was less than that of the control group(1.11 + 0.31)(P<0.05).5. Correlation analysis showed that there were no correlations between the copy numbers of fecal Bifidobacterium, Lactobacillus and Bacteroides and FPG、TC、TG、HDL-C、LDL-C、IL-1β、IL-6、TNF-α and BMI(P>0.05); there were no correlations between the intestinal Lactobacillus/Bacteroides ratio and the intestinal Bifidobacterium/Bacteroides ratio in case group and inflammatory cytokines and PANSS positive points, negative points, general pathologic points and the total scores(P >0.05). Conclusions1. The first-episode schizophrenia patients exist intestinal flora disorder and intestinal flora proportion imbalance, suggesting the imbalance of intestinal flora proportion may be involved in the pathogenesis of schizophrenia.2. The first-episode schizophrenia patients exist immune disorder mediated by cytokines, inflammatory cytokines IL-1β、IL-6、TNF-α were higher than normal humans.3. There were no direct correlations between the copy numbers of fecal Bifidobacterium, Lactobacillus and Bacteroides and blood glucose, lipid metabolism and serum inflammatory cytokines in schizophrenia patients, and there were no significant correlations between the imbalance of intestinal flora proportion and inflammatory cytokines and the PANSS total scores.