Study On The Changes Of Intestinal Microflora In Children With Epilepsy Based On 16S RRNA

OBJECTIVES:（1）To study the differences in gut flora between children with epilepsy and healthy children.（2）To investigate the relationship between certain specific flora and epilepsy.METHODS:Stool specimens from children with first diagnosed epilepsy and not on antiepileptic drugs who were hospitalized in the inpatient department of pediatrics Foshan Maternal and Child Health Hospital affiliated to Southern Medical University from July 1,2021 to October 31,2022,as well as healthy children（some of whom were healthy children of the hospital’s employees）who were routinely examined by the child health department of the hospital,were collected,and total DNA was extracted and then amplified by 16SrRNA sequencing technology was used to identify microbial species,and the differences in intestinal flora were analyzed using bioinformatics methods.SPSS26.0 software was used to statistically assess the experimental data.RESULTS:（1）In terms of alpha diversity,the faith pd index of the epileptic children group was 31.70 ± 14.98,the Chao1 index was 270.99 ± 152.94,the observed features index was 270.42±152.50,the Shannon index was 4.47±1.26,and the Simpson index was 0.89（0.79,0.94）,and 26.54±8.73,223.49±105.77,223.07±105.50,4.10±0.83,0.85（0.79,0.90）in the healthy children group,respectively,and only the difference in the faith pd index was statistically significant in both groups（P=0.042）.（2）In terms of β-diversity,the differences in Bray Curtis index,Unweighted Unifrac index and Weighted Unifrac index were statistically significant（p-values 0.006,0.034,0.007,respectively）.Principal component analysis showed that the degree of explanation of the first principal component was 14.910%,the degree of explanation of the second principal component was 7.431%,and the degree of explanation of the third principal component was 6.390%,with statistically significant differences in the compositional structure（F=2.208;P=0.005）.（3）The structure of the intestinal flora was disturbed in the group of children with epilepsy compared to the healthy controls.At the phylum level,the abundance of the thick-walled phylum was significantly enriched in the epilepsy case group（P=0.023）and the phylum Aspergillus in the healthy control group（P=0.023）;at the phylum level,the abundance of the phylum C.aspergillus was significantly higher in the healthy control group than in the epilepsy case group（P=0.040）;at the family level and genus level,the family Veronaceae and the genus Megacoccus were significantly enriched in the epilepsy children group（P value:0.048,0.0006）.（4）The healthy control group was significantly enriched in human disease,cellular processes,environmental information processing,membrane transport,and cell colony-prokaryotic pathways,while the epileptic group was significantly enriched in metabolic and alanine,aspartate,and glutamate metabolic pathways（P<0.05 for all）.（5）Then,we analyzed the intestinal flora of children with ≥4 and<4 seizures within the epilepsy group,and the chaol and observedfeatures indices of the intestinal flora of children with<4 seizures were higher than those of children with≥4 seizures（all P values<0.05）.（6）The Bray Curtis index and Unweighted Unifrac index in β-diversity were statistically significant（P value 0.001 and 0.005,respectively）,and the results of principal component analysis showed that the first principal component explained 16.340%,the second principal component explained 7.575%,and the third principal component explained 6.349%in both groups.The difference in the composition structure was statistically significant（F=2.305;P=0.003）.（7）At all levels of intestinal flora,the group of children with epilepsy with<4 seizures had thick-walled bacilli and the phylum TM7,Clostridia,Erysipelotrichia,TM7₃ Clostridiales,Lachnospiraceae,Blaut Blautia,Ruminococcus,and Coprococcus,and Pseudomonadales and Pseudomonadaceae were significantly enriched in the group of children with epilepsy with ≥4 seizures（all P values<0.05）.The L-isoleucine and L-glutamine biosynthetic pathways were reduced in the group with≥4 seizures compared to the group with<4 seizures.CONCLUSIONS:（1）Compared with the healthy children group,the epileptic children group has an increase in pathogenic bacteria and a decrease in potential beneficial bacteria.The metabolic pathways of alanine,asiatic acid and glutamine acid are significantly enriched.The distribution of intestinal bacteria in different seizure frequency groups is also different,and there is different degrees of biosynthesis damage.（2）The group of children with epilepsy is more abundant in Veronicaceae and macrococci than the group of healthy children,and these two kinds of bacteria may be linked to the onset of epilepsy.