Probiotics: Shaping the gut immunological responses

Probiotics are live microorganisms exerting beneficial effects on the host’s health when administered in adequate amounts.Among the most popular and adequately studied probiotics are bacteria from the families Lactobacillaceae,Bifidobacteriaceae and yeasts.Most of them have been shown,both in vitro and in vivo studies of intestinal inflammation models,to provide favorable results by means of improving the gut microbiota composition,promoting the wound healing process and shaping the immunological responses.Chronic intestinal conditions,such as inflammatory bowel diseases(IBD),are characterized by an imbalance in microbiota composition,with decreased diversity,and by relapsing and persisting inflammation,which may lead to mucosal damage.Although the results of the clinical studies investigating the effect of probiotics on patients with IBD are still controversial,it is without doubt that these microorganisms and their metabolites,now named postbiotics,have a positive influence on both the host’s microbiota and the immune system,and ultimately alter the topical tissue microenvironment.This influence is achieved through three axes:(1)By dis-placement of potential pathogens via competitive exclusion;(2)by offering protection to the host through the secretion of various defensive mediators;and(3)by supplying the host with essential nutrients.We will analyze and discuss almost all the in vitro and in vivo studies of the past 2 years dealing with the possible favorable effects of certain probiotic genus on gut immunological responses,highlighting which species are the most beneficial against intestinal inflammation.

The protective role of prebiotics and probiotics on diarrhea and gut damage in the rotavirus-infected piglets

Rotavirus is one of the pathogenic causes that induce diarrhea in young animals, especially piglets, worldwide. However, nowadays, there is no specific drug available to treat the disease, and the related vaccines have no obvious efficiency in some countries. Via analyzing the pathogenesis of rotavirus, it inducing diarrhea is mainly due to disturb enteric nervous system, destroy gut mucosal integrity, induce intracellular electrolyte imbalance, and impair gut microbiota and immunity. Many studies have already proved that prebiotics and probiotics can mitigate the damage and diarrhea induced by rotavirus infection in hosts. Based on these, the current review summarizes and discusses the effects and mechanisms of prebiotics and probiotics on rotavirus-induced diarrhea in piglets. This information will highlight the basis for the swine production utilization of prebiotics and probiotics in the prevention or treatment of rotavirus infection in the future.

A Comprehensive Analysis of Efficacy and Safety of Probiotics in Inflammatory Bowel Disease

Introduction: Inflammatory bowel disease (IBD) affects approximately 7 million people worldwide. In the U.S. alone, per the CDC, 1.3% of adults, which is approximately 3,000,000 people, are diagnosed with inflammatory bowel disease-either, Crohn’s disease, or ulcerative colitis. The estimated cost of treatment can be close to $23,000 annually, with treatment regimens comprising biologic agents and anti-inflammatory therapies. Probiotics have recently gathered interest as a low-cost additional therapy option that, in addition to the current regimen of IBD management, allows for reductions in rates of IBD flare-ups by significantly reducing the number of emergency room visits and avoiding the need to constantly escalate treatment by addition of biologic agents in achieving remission. The Analysis Goal: Our research project aimed to see if there was a significant difference in the addition of probiotics to standard therapy in inflammatory bowel disease by comparing existing research studies and trials. We analyzed RCTs published in PubMed to assess the efficacy and safety of probiotics in patients with IBD in preventing frequent disease flare-ups and reducing the cost of care. Research Methods: We did a comparative analysis of available RCTs using a PubMed search and included studies that researched the addition of probiotic strains in patients with IBD (ulcerative colitis and Crohn’s disease). After reviewing the inclusion and exclusion criteria, the trials selected for analysis were reviewed by two independent reviewers. Results: We analyzed 21 RCTs, and 16 RCTs (76.2%) showed that probiotics are an effective therapy for IBD, inducing remission and reducing flare-up rates in patients on a standard treatment regimen. Conclusion: Probiotics given in combination with standard therapy in IBD are effective in decreasing disease activity rates and reducing remission rates. No significant adverse reactions to probiotics were noticed.

A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

Background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public alike.There has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut microbiota.However,compared to other ergogenic aids and dietary supplements,probiotics present unique study challenges.The objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active individuals.Methods:Four databases(MEDLINE,CINAHL,Cochrane CENTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active individuals.An intervention with probiotics and inclusion of a control and/or placebo group were essential.Only peer-reviewed articles in English were considered,and there were no date restrictions.Results were extracted and presented in tabular form to detail study protocols,characteristics,and outcomes.Bias in randomized controlled trials was determined with the RoB 2.0 tool.Results:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over design.Approximately half the studies used a single probiotic and the other half a multi-strain preparation.The probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 days.Fewer than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut microbiota.The sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated females.Low-level adverse events were reported in only 2 studies,although the methodology of reporting varied widely.The risk of bias was generally low,although details on randomization were lacking in some studies.Conclusion:There is a substantial body of research on the effects of prob iotic supplementation in healthy athletes and physically active individuals.Considerable heterogeneity in probiotic selection and dosage as well as outcome measures has made clinical and mechanistic interpretation challenging for both health care practitioners and researchers.Attention to issues of randomization of participants,treatments and interventions,selection of outcomes,demographics,and reporting of adverse events will facilitate more trustworthy interpretation of probiotic study results and inform evidence-based guidelines.

Research advances on encapsulation of probiotics with nanomaterials and their repair mechanisms on intestinal barriers

Probiotics participate in various physiological activities and contribute to body health.However,their viability and bioefficacy are adversely affected by gastrointestinal harsh conditions,such as gastric acid,bile salts and various enzymes.Fortunately,encapsulation based on various nanomaterials shows tremendous potential to protect probiotics.In this review,we introduced some novel encapsulation technologies involving nanomaterials in view of predesigned stability and viability,selective adhesion,smart release and colonization,and efficacy exertion of encapsulated probiotics.Furthermore,the interactions between encapsulated probiotics and the gastrointestinal tract were summarized and analyzed,with highlighting the regulatory mechanisms of encapsulated probiotics on intestinal mechanical barrier,chemical barrier,biological barrier and immune barrier.This review would benefit the food and pharmaceutical industries in preparation and utilization of multifunctional encapsulated probiotics.

Function and Application Progress of Probiotics in Food

Probiotics have a long history of use in human production and life.With the gradual deepening of the research on the functions of probiotics,their various nutritional and health benefits for the human body have also become increasingly clear.Existing research shows that probiotics can regulate intestinal flora,and improve immunity and even the symptoms of some diseases.Therefore,in the food industry,the application of probiotics from traditional fermented foods to functional foods has become more and more extensive.In this paper,the research progress of nutritional function and application of probiotics in food at home and abroad was reviewed,in order to provide some reference for the safe application of probiotics in food.

Effects of oral probiotics on inflammation and intestinal function in adult patients after appendectomy:Randomized controlled trial

BACKGROUND Appendectomy is an acute abdominal surgery that is often accompanied by severe abdominal inflammation.Oral probiotics are one of the postoperative treatments for rapid rehabilitation.However,there is a lack of prospective studies on this topic after appendectomy.AIM To investigate whether the postoperative probiotics can modulate the inflammatory response and restore intestinal function in patients following appendectomy.METHODS This was a prospective,randomized trial.A total of 60 emergency patients were randomly divided into a control group(n=30)and a probiotic group(n=30).Patients in the control group started to drink some water the first day after surgery,and those in the probiotic group were given water supplemented with Bacillus licheniformis capsules for 5 consecutive days postsurgery.The indices of inflammation and postoperative conditions were recorded,and the data were analyzed with RStudio 4.3.2 software.RESULTS A total of 60 participants were included.Compared with those in the control group,the C-reactive protein(CRP),interleukin 6 and procalcitonin(PCT)levels were significantly lower in the probiotic group at 2 d after surgery(P=2.224e-05,P=0.037,and P=0.002,respectively,all P<0.05).This trend persisted at day 5 post-surgery,with CRP and PCT levels remaining significantly lower in the probiotic group(P=0.001 and P=0.043,both P<0.05).Furthermore,probiotics0.028,both P<0.05).CONCLUSION Postoperative oral administration of probiotics may modulate the gut microbiota,benefit the recovery of the early inflammatory response,and subsequently enhance recovery after appendectomy.

Effects of Compound Probiotics on Growth Performance and Intestinal Flora of Kunming Mice

[Objectives]This study was conducted to investigate the effects of adding compound probiotics on the growth performance and intestinal flora of Kunming mice.[Methods]Twelve healthy 2-week-old Kunming male mice with body weight of(11.09±0.43)g were selected.They were randomly divided into two treatment groups,namely blank control group(NC)and compound probiotics group(CB+LR+BS),with six mice in each group.The two groups were fed with commercial basal diet,and the compound probiotic experimental group was fed with basal diet supplemented with compound probiotics,in which the contents of Clostridium butyricum spores,Lactobacillus reuteri and Bacillus subtilis spores were 1×1010,1×1011 and 1×1010 CUF/kg,respectively.The body weight,feed intake and water intake of mice were counted every 4 d,and the experimental period was 13 d.On the 13 th day,the cecal contents of the mice were collected for analysis.[Results]There was no significant change in body weight and feed intake when compound probiotics were added to the diet.However,the addition of compound probiotics reduced the abundance of harmful bacteria such as Escherichia coli,urease-negative Helicobacter typhlonius and Salmonella enterica,while increasing the abundance of beneficial bacteria such as Anaerostipes hadrus,and the contents of IgG and IgM increased significantly(P<0.05).[Conclusions]In summary,the addition of compound probiotics could significantly improve the structure of intestinal microbial flora,increase the quantity of beneficial bacteria,reduce the quantity of harmful bacteria,and improve the immune function of mice.

Effects of A Multi-Enzyme Complex or Probiotic Supplementation on Performance and Nutrient Digestibility of Broiler Chicks

This experiment was conducted to determine whether the performance of broilers fed diets based on corn and soybean meal could be enhanced with enzymes or probiotics. A total of 120 male broilers, three days of age, were assigned to one of four treatments in a completely randomized design, and housed in groups of five with six cages per treatment. The control diet was based on corn and soybean meal while the three experimental diets consisted of the basal diet supplemented with 0.1% of enzyme I, enzyme II, or probiotic. Enzyme I provided α-galactosidase and fl-mannanase, while enzyme II provided protease, amylase, α-galactosidase, xylanase, and cellulase. The probiotic was composed of Bacillus coagulance, Bacillus lichenformis , Bacillus subtilis , and Clostridium butyricum. Over the 28 day experiment, the weight gain of birds fed the probiotic treatment was superior （P = 0.03 ） to the control, while gains for the enzyme treatments were intermediate to those of the control and probiotic. Feed intake and feed conversion did not differ among treatments （P 〉 0.05 ）. Ammonia production was significantly （ P 〈 0.01 ） higher in the control compared with either of the enzyme or probiotic treatments. Compared with the control, supplementation with enzyme H significantly reduced the digestibility of arginine, isoleucine, and lysine （P 〈 0.05 ）. In contrast, the digestibility of energy was higher （P 〈 0.01 ） for birds supplemented with enzyme II than the control. Digestibility coeffi- cients did not differ for any other parameter with the exception of energy which was significantly higher for birds fed the probiotic treatment than the control （P 〈 0.01 ）. In summary, the performance of broilers was significantly enhanced by the addition of a probiotic to the diet. However, under the conditions of this experi- ment, supplementation with a multi-enzyme complex containing either α-galactosidase and fl-mannanase or the combination of protease, amylase, galactosidase, xylanase, and cellulase failed to improve broiler performance.

Research progress on the mechanism of exercise fatigue and the role of probiotics in counteracting it

Exercise fatigue is a physiological phenomenon where the body cannot maintain a specific level after being stimulated by excessive exercise.Its five main theories include“energy depletion”,“accumulation of metabolites”,“homeostasis disorder of the internal environment”,“free radicals”,and“central nervous system protection inhibition”.The imbalance of intestinal flora caused by vigorous exercise can further lead to fatigue.Therefore,maintaining healthy intestinal flora is crucial for athlete health and performance.Recent studies have demonstrated that probiotics can regulate intestinal flora and alleviate exercise fatigue;however,there are no systematic reviews on the anti-fatigue effects of probiotics.Based on the mechanisms of exercise-induced fatigue,this article summarizes the effects and mechanisms by which probiotics combat exercise fatigue,aiming to provide research ideas for the development of probiotics that prevent exercise fatigue.

Clinical Evaluation of Enteral Nutrition+Probiotics in the Treatment of Gastrointestinal Dysfunction After Severe Traumatic Brain Injury

Objective:To evaluate the therapeutic effect of enteral nutrition+probiotics in patients with gastrointestinal dysfunction after severe craniocerebral injury.Methods:From September 2018 to February 2023,80 patients(20-82 years old)with gastrointestinal dysfunction who were admitted to the Intensive Care Unit at the Third People’s Hospital of Xining were included in the study.Their primary condition was severe craniocerebral injury,and all of them received conventional symptomatic treatment.Group A received enteral nutrition+probiotic therapy,whereas group B received enteral nutrition only.The differences in the following indicators were compared before and after treatment:nutritional and biochemical indicators,gastrointestinal function indicators,Glasgow Coma Scale(GCS),Sequential Organ Failure Assessment(SOFA),APACHE II score,serum procalcitonin(PCT),neutrophil(N)ratio,and C reactive protein(CRP).Result:The nutritional and biochemical indicators in group A were higher than those in group B,P<0.05;the time to first passage of flatus,time to first passage of stool,and bowel sound recovery time in group A were shorter than those in group B,P<0.05;the GCS of group A was higher than that of group B,P<0.05;the SOFA and APACHEⅡscores of group A were not different from those of group B,P>0.05;and the PCT,N ratio,and CRP levels of group A were lower than those of group B,P<0.05.Conclusion:In patients with gastrointestinal dysfunction after severe craniocerebral injury,enteral nutrition+probiotic therapy is highly effective and feasible,as it can optimize various nutritional indicators,shorten the gastrointestinal function recovery time,and reduce the body’s stress response.

Effect of Early Enteral Nutrition Combined with Probiotics on the Nutritional Status of Patients with Severe Craniocerebral Injury

Objective:To observe the effect of early enteral nutrition combined with probiotics on the nutritional status of patients with severe craniocerebral injury.Methods:Thirty-five patients with severe craniocerebral injury were divided into the study group(17 patients)and the control group(18 patients)according to the method of a randomized numerical table;both groups of patients started enteral nutrition via nasogastric tube within 24–48 hours after admission to the hospital,and probiotics were given in addition to the study group.Hemoglobin,total plasma protein,albumin,prealbumin,cholinesterase,fasting blood glucose,and other indexes were monitored before and early morning after enteral nutrition support,and upper arm circumference(AC),triceps skinfold thickness(TSF),and upper arm muscle circumference(AMC)were measured,and gastrointestinal response and time to first defecation of the patients were observed and compared with GCS score.Results:The hemoglobin,serum albumin,prealbumin,cholinesterase,and total plasma protein levels in the study group were significantly higher and fasting blood glucose levels were significantly lower than those in the control group after treatment(P<0.05).The incidence of reflux and constipation in the study group was lower than that in the control group,and the time to first defecation was shorter than that in the control group(P<0.05).After treatment,AC,TSF,and AMC were higher in the study group than in the control group(P<0.05).GCS scores were significantly higher in both groups after treatment,but the trend was more pronounced in the study group(P<0.05).Conclusion:Compared with simple enteral nutrition,enteral nutrition combined with probiotics can better correct metabolic disorders after heavy craniocerebral injury and improve the nutritional status of patients.

Effects of Compound Probiotics on Intestine and Intestinal Aeromonas hydrophila of Fish

[Objective] This study was conducted to develop compound probiotics that can be used as the alternatives of chemical drugs and antibiotics in aquaculture. [Method] Different concentrations of EM （effective microorganisms） and Bacillus amyloliquefaciens were mixed at a ratio of 1：1, and sprayed on fish feed. The growth of intestinal villi of the fishes that had been fed with the feed mixed with compound probiotics for three months was observed; meanwhile, the content of in- testinal Aeromonas hydrophila was detected by real-time quantitative PCR. ｜Result] The compound probiotics promoted the development of intestinal villi, and inhibited the growth of A. hydrophila, and the effects were also concentration dependent. However, the compound probiotics did not increase the thickness of the intestinal serous layer, muscular layer and submucosal layer. [Conclusion] The compound probiotics we prepared can be used and popularized in aquiculture as it can inhibit the growth of A. hydrophila.

Effects of Probiotics on Growth Performance and Blood Biochemical Indexes of Cherry Valley Ducks

In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight （P〈0.05） of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood （P〈0.05） and reduce the creatinine content and total cholesterol content in Cherry Valley ducks （P〉0.05）; at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic.

Effects of Different Concentrations of Homologous Probiotics on Small Intestinal Mucosa Structure of 42-day-old Broilers

In the study, the methods of applied histology and histochemistry were used to determine intestinal villus length, crypt depth, the ratio of intestinal villus length to crypt depth, mucous membrane thickness and intestinal wall thickness of duodenum, jejunum and ileum of 42-day-old broilers, so as to study the effects of different conncentrations of homologous probiottcs on small intestinal mucosa struc- ture of the broilers. The results showed that the effect of 0.3% probiotics on small intestine mucosal structures was the best, such as the length of intestinal villus was the longest, the ratio of villus length to crypt depth was the largest, the thins of mucous membrane and intestinal wall was the thickest. These showed that 0,3% probiotics had best effect on improving and enhancing the digestion-absorption func- tion of the small intestine of the broilers.

Probiotics in Helicobacter pylori eradication therapy: A systematic review and meta-analysis

AIM: To summarize the evidence from randomized controlled trials(RCTs) regarding the effect of probiotics by using a meta-analytic approach.METHODS: In July 2013, we searched PubM ed, EMBASE, Ovid, the Cochrane Library, and three Chinese databases(Chinese Biomedical Literature Database, Chinese Medical Current Content, and Chinese Scientific Journals database) to identify relevant RCTs.We included RCTs investigating the effect of a combination of probiotics and standard therapy(probiotics group) with standard therapy alone(control group).Risk ratios(RRs) were used to measure the effect of probiotics plus standard therapy on Helicobacter pylori(H.pylori) eradication rates, adverse events, and patient compliance using a random-effect model.RESULTS: We included data on 6997 participants from 45 RCTs, the overall eradication rates of the probiotic group and the control group were 82.31% and 72.08%, respectively.We noted that the use of probiotics plus standard therapy was associated with an increased eradication rate by per-protocol set analysis(RR = 1.11; 95%CI: 1.08-1.15; P < 0.001) or intention-totreat analysis(RR = 1.13; 95%CI: 1.10-1.16; P < 0.001).Furthermore, the incidence of adverse events was 21.44% in the probiotics group and 36.27% in the control group, and it was found that the probiotics plus standard therapy significantly reduced the risk of adverse events(RR = 0.59; 95%CI: 0.48-0.71; P < 0.001), which demonstrated a favorable effect of probiotics in reducing adverse events associated with H.pylori eradication therapy.The specific reduction in adverse events ranged from 30% to 59%, and this reduction was statistically significant.Finally, probiotics plus standard therapy had little or no effect on patient compliance(RR = 0.98; 95%CI: 0.68-1.39; P = 0.889).CONCLUSION: The use of probiotics plus standard therapy was associated with an increase in the H.pylori eradication rate, and a reduction in adverse events resulting from treatment in the general population.However, this therapy did not improve patient compliance.

Are probiotics useful in Helicobacter pylori eradication?

Helicobacter pylori(H. pylori) is considered an etiologic factor for the development of peptic ulcer disease,gastric adenocarcinoma, and MALT lymphoma.Therapeutic schemes to eradicate the bacteria are based on double antibiotic therapy and proton pump inhibitor. Despite many therapeutic improvements in H. pylori eradication treatment, it is still associated with high infection rate also in developed countries.Bacterial resistance and adverse events occurrence are among most frequent causes for anti- H. pylori treatment failure. Several studies have reported that certain probiotic strains can exhibit inhibitory activity against H. pylori bacteria. In addition, some probiotic strains can reduce the occurrence of side effects due to antibiotic therapy and consequently increase the H.pylori eradication rate. The results of the prospective double-blind placebo-controlled studies suggest that specific probiotics, such as S. boulardii and L.johnsonni La1 probably can diminish the bacterial load,but not completely eradicate the H. pylori bacteria.Furthermore, it seems that supplementation with S. boulardii is a useful concomitant therapy in the standard H. pylori eradication treatment protocol and most probably increases eradication rate. L. reuteri is equally effective, but more positive studies are needed. Finally, probiotic strains, such as S. boulardii,L. reuteri and L. GG, decrease gastrointestinal antibiotic associated adverse effects.

Relationship between intestinal microbiota and ulcerative colitis:Mechanisms and clinical application of probiotics and fecal microbiota transplantation

Ulcerative colitis(UC) is an inflammatory disease that mainly affects the colon and rectum. It is believed that genetic factors, host immune system disorders, intestinal microbiota dysbiosis, and environmental factors contribute to the pathogenesis of UC. however, studies on the role of intestinal microbiota in the pathogenesis of UC have been inconclusive. Studies have shown that probiotics improve intestinal mucosa barrier function and immune system function and promote secretion of anti-inflammatory factors, thereby inhibiting the growth of harmful bacteria in the intestine. Fecal microbiota transplantation(FMT) can reduce bowel permeability and thus the severity of disease by increasing the production of short-chain fatty acids, especially butyrate, which help maintain the integrity of the epithelial barrier. FMT can also restore immune dysbiosis by inhibiting Th1 differentiation, activity of T cells, leukocyte adhesion, and production of inflammatory factors. Probiotics and FMT are being increasingly used to treat UC, but their use is controversial because of uncertain efficacy. Here, we briefly review the role of intestinal microbiota in thepathogenesis and treatment of UC.

Systematic review of randomised controlled trials:Probiotics for functional constipation

AIM:To systematically evaluate and update evidence on the efficacy and safety of probiotic supplementation for the treatment of constipation. METHODS:The MEDLINE,EMBASE,CINAHL,and Cochrane Library databases were searched in May 2009 for randomised controlled trials(RCTs)performed in paediatric or adult populations related to the study aim. RESULTS:We included five RCTs with a total of 377 subjects(194 in the experimental group and 183 in the control group).The participants were adults (three RCTs,n=266)and children(two RCTs,n= 111)with constipation.In adults,data suggests a favourable effect of treatment with Bifidobacterium lactis DN-173 010,Lactobacillus casei Shirota,and Escherichia coli Nissle 1917 on defecation frequency and stool consistency.In children,L.casei rhamnosusLcr35,but not L.rhamnosus GG,showed a beneficial effect. CONCLUSION:Until more data are available,we believe the use of probiotics for the treatment of constipation condition should be considered investigational.

Remission induction and maintenance effect of probiotics on ulcerative colitis: A meta-analysis

AIM:To evaluate the induction of remission and main-tenance effects of probiotics for ulcerative colitis.METHODS: Information was retrieved from MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. The induction of remission and promotion of mainte-nance were compared between probiotics treatment and non-probiotics treatment in ulcerative colitis.RESULTS: Thirteen randomized controlled studies met the selection criteria. Seven studies evaluated the remission rate, and eight studies estimated the recur-rence rate; two studies evaluated both remission and recurrence rates. Compared with the non-probiotics group, the remission rate for ulcerative colitis patients who received probiotics was 1.35 (95% CI: 0.98-1.85). Compared with the placebo group, the remission rate of ulcerative colitis who received probiotics was 2.00 (95% CI: 1.35-2.96). During the course of treatment, in patients who received probiotics for less than 12 mo compared with the group treated by non-probiotics, the remission rate of ulcerative colitis was 1.36 (95% CI: 1.07-1.73). Compared with the non-probioticsgroup, the recurrence rate of ulcerative colitis patients who received probiotics was 0.69 (95% CI: 2.47-1.01). In the mild to moderate group who received probiotics, compared to the group who did not receive probiotics, the recurrence rate was 0.25 (95% CI: 0.12-0.51). The group who received Bifidobacterium bifidum treatment had a recurrence rate of 0.25 (95% CI: 0.12-0.50) compared with the non-probiotics group.CONCLUSION: Probiotic treatment was more effec-tive than placebo in maintaining remission in ulcerative colitis.