Lactobacillus In Promoting Gastrointestinal Motility In Rats With Severe Head Injury

Objective: Gastrointestinal motility disturbance (GMD) is the most common complication of severe head injury (SHI). It is characterized by lower esophageal sphincter tone, gastrointestinal motility inhibition, etc, cause vomiting, pain and distention even aspiration pneumonia, severe malnutrition, sepsis and multiple organ dysfunction, which leads to clinical patients intolerate in early enteral nutrition. Lactobacillus is an important component of probiotics. It can fermente carbohydrates into a lot of lactic acid and acetic acid. Prebiotics can selectively stimulate the growth of intestinal bacteria, including Dietary fiber, pectin and fructooligosaccharides, etc. Many studies have shown that lactobacillus and synbiotics (mixture by probiotics and prebiotics) are benefit to gastrointestinal function, such as adjusting the balance of intestinal flora, promoting the proliferation of intestinal epithelial cell, inhibiting intestinal inflammation, maintening intestinal barrier integrity, reducing incidence of endotoxin and sepsis. To date, lactobacillus and synbiotics have been widely used to improve the GMD caused by functional dyspepsia, or nfection, or irritable bowel syndrome, etc. However, few works have done on the its'effect on GMD after SHI. Therefore, we conducted this experimental study to find out whether lactobacillus and synbiotics can improve gastrointestinal motility disturbance after SHI.Methods: The SHI rats model was established by air percussion, and randomly divided into three treatment groups (group A, B and C), wo also set a control group without head injury, named group D. group A and D received the standard enteral diet TRENSINE(SANJIU Co. Ltd., Guangdong, China);group B received TRENSINE plus Lactobacillus(including Pediacoccus pentoseceus, Lactococcus raffinolactis, Lactobacillus paracasei subsp paracasei, Lactobacillus plantarum). group C received TRENSINE plus synbiotics(including L. plantarum, Lactobacillus casei, Lactococcus, Pediococcus pentosaceus,and four fermantable fibres: betaglucan, inulin, pectin, resistant starch). Group D without head injury (sham-operated) received the standard enteral diet TRENSINE. group A, B, C, D were fed enteral nutrition (125kcal/kg body weight per day) by gastric irrigation, Lactobacillus (3.2×1010cfu/kg body weight per day per rat)were added to the enteral nutrition in group B; Lactobacillus (3.2×1010cfu/kg body weight per day per rat) and fermantable fibres(480mg/kg body weight per day per rat) were added to the enteral nutrition in group C. The blood, gastric mucosa, gastrointestinal and tissue were collected for analysis on days1, 3and 7 after SHI.Results:1. Change in rats'gastric emptyingSHI induced an increase in relative residual rates of gastric stain on the first day (A vs D, P <0.01, B, C vs D, P <0.05). On the third day after SHI, group B and C (but not A) had reached that in group D (B,C vs D, P> 0.05,A vs D, P <0.05); The gastric emptying was faster in group B than in group A(B vs A, P <0.05).group A reached that group D on the seventh after SHI(A vs D,P> 0.05).2. Change in rats'intestinal transitSHI induced a decrease in rats'intestinal transit on the first day (A, C vs D, P <0.01, B vs D, P<0.05). On the third day after SHI, group B (but not A and C) had reached that in group D(B vs D, P> 0.05,A,C vs D, P <0.01, P <0.05);The intestinal transit was faster in group B and C than in group A(B,C vs A, P <0.01, P <0.05). Group A reached that group D on the seventh after SHI (A vs D, P> 0.05).3. Change in MTL level in rats'plasma and gastrointestinal tissue3.1 Plasma MTL levelSHI induced an increase in plasma MTL level on the first day (A vs D, P<0.01, B, C vs D, P<0.05). On the third day after SHI, both group B and C (but not A) had reached that in group D (B, C vs D, P> 0.05, A vs D, P<0.01); The level of plasma MTL was lower in group B than in group A (B vs A, P<0.05).group A reached that group D on the seventh after SHI (A vs D, P> 0.05).3.2 Gastric antrum MTL levelSHI induced an increase in gastric antrum MTL level on the first day (A, B, C vs D, P <0.05). On the third day after SHI, group B (but not A and C) had reached that in group D (B vs D, P>0.05, A, C vs D, P<0.05).group A and C reached that group D on the seventh after SHI (A, C vs D,P>0.05). 3.3 Jeunal tissue MTL levelSHI induced a increase in jeunal tissue MTL level on the first day (A, B, C vs D, P <0.01). On the third day after SHI, The level of jeunal tissue MTL in group A,B,C still higher than in group D(B vs D,P<0.05, A,C vs D, P<0.01).group A,B,C reached that group D on the seventh after SHI(A,B,C vs D,P>0.05).4. Change in CGRP levels in rats'plasma and gastrointestinal tissue4.1 Plasma CGRP levelSHI induced an increase in levels on the first day (A, C vs D, P<0.01, B vs D, P<0.05). On the third day after SHI, group B and C (but not A) had reached that in group D (B, C vs D, P>0.05, A vs D, P<0.05). The level of plasma CGRP in group B was higher than in group A (B vs A, P<0.05).group A reached that group D on the seventh after SHI (A vs D, P>0.05).4.2 Gastric antrum tissue CGRP levelSHI induced an increase in gastric antrum CGRP levels on the first day (A, B vs D, P<0.05, C vs D, P<0.01). On the third day after SHI, group B and C (but not A) had reached that in group D (B, C vs D, P>0.05, A vs D, P<0.05). The level of gastric antrum CGRP in group B was higher than in group A (B vs A, P<0.05).group A reached that group D on the seventh after SHI (A vs D, P>0.05).4.3 Jeunal tissue CGRP levelSHI induced a increase in jeunal tissue CGRP levels on the first day (Avs D, P<0.01, B, C vs D, P<0.05). On the third day after SHI, g jeunal tissue roup B and C (but not A) had reached that in group D (B, C vs D, P>0.05, A vs D, P<0.05). The level of jeunal tissue CGRP in group B was higher than in group A (B vs A, P<0.05).group A reached that group D on the seventh after SHI (A vs D, P>0.05).5. Stomach floraDGGE analysis showed there was little bacteria in group D. SHI could disturb the balance of rats gastric microflora, and lead to pathogenic bacteria overgrowth. On the first day after SHI, The number of bacteria increased remarkably in group A,B and C, changes happened of intragastric advantage bacteria in group B. but there was no difference about richness, diversity and evenness of total bacteria in group A,B and C(P> 0.05).On the third day after SHI, the number of bacteria decreased in group A, B and C. Intragastric advantage bacteria changes also could be seen in group B. After analysis, the richness and diversity of total bacteria decreased remarkably (B vs A, C, P <0.01), but there was no difference about the evenness of total bacteria in group A, B and C(P> 0.05).On the seventh day after SHI, the number of bacteria also decreased in group A,B and C, especially in group B. DGGE analysis indicated that the richness and diversity of total bacteria in group C increased remarkably(C vs B,A, P<0.01). But there was no difference about the evenness of total bacteria in group A, B and C (P> 0.05).6. Weight lossWeight loss decreased remarkably one week after SHI and was not corrected by lactobacillus and synbiotics. There were no statistical difference among group A, B and C (P> 0.05).Conclusion:1.SHI induced delayed gastric emptying and intestinal transit decreased. Enteral nutrition, Lactobacillus and Synbiotics could accelerate gastric residual pigment discharge and improve intestinal transit rate.2.The improvement of gastric emptying rate and small intestinal transit capacity, Group lactobacillus is better than group enteral nutrition and synbiotics. On the third day after SHI, gastrointestinal motility in group lactobacillus had recovered mainly.3.Lactobacillus can inhibit gastric pathogenic bacteria reproduction after SHI. After injury 7d, the number of gastric pathogenic bacteria in group lactobacillus was significantly less than group synbiotics.4.Lactobacillus and synbiotics in combination with enteral nutrition can reduce rats'plasma, gastrointestinal tissue MTL and CGRP level after SHI. Group lactobacillus is better than group enteral nutrition and synbiotics, group synbiotics is better than group enteral nutrition.