Prevention and treatment of antibiotics-associated adverse effects through the use of probiotics: A review

BACKGROUND

The human gut hosts a diverse microbial community, essential for maintaining overall health. However, antibiotics, commonly prescribed for infections, can disrupt this delicate balance, leading to antibiotic-associated diarrhea, inflammatory bowel disease, obesity, and even neurological disorders. Recognizing this, probiotics have emerged as a promising strategy to counteract these adverse effects.

AIM OF REVIEW

This review aims to offer a comprehensive overview of the latest evidence concerning the utilization of probiotics in managing antibiotic-associated side effects.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Probiotics play a crucial role in preserving gut homeostasis, regulating intestinal function and metabolism, and modulating the host immune system. These mechanisms serve to effectively alleviate antibiotic-associated adverse effects and enhance overall well-being.

Clinical impact of diarrhea during enteral feeding after esophagectomy

BACKGROUND

Enteral feeding (EF) is recommended to enhance nutritional status after esophagectomy; however, diarrhea is a common complication of EF. We investigated the clinical and prognostic impact of diarrhea during EF after esophagectomy.

METHODS

One hundred and fifty-two patients who underwent transthoracic esophagectomy were enrolled. The King's stool chart was used for stool characterization. The short- and long-term outcomes were compared between a non-diarrhea (Group N) and diarrhea group (Group D).

RESULTS

A higher dysphagia score (≥ 1) was observed more frequently in Group D than in Group N (45.7% vs. 19.8%, p = 0.002). Deterioration of serum total protein, serum albumin, serum cholinesterase, and the prognostic nutritional index after esophagectomy was greater in Group D than in Group N (p = 0.003, 0.004, 0.014, and 0.001, respectively). Patients in Group D had significantly worse overall survival (OS) and recurrence-free survival (RFS) than those in Group N (median survival time (MST): OS, 21.9 vs. 30.6 months, p = 0.001; RFS, 12.4 vs. 27.7 months, p < 0.001). In stratified analysis due to age, although there was no difference in OS with or without diarrhea in young patients (MST: 24.1 months in a diarrhea group vs. 33.6 months in a non-diarrhea group, p = 0.218), patients in a diarrhea group had significantly worse OS than those in a non-diarrhea group in elderly patients (MST: 17.8 months vs. 27.9 months, p < 0.001).

CONCLUSIONS

Diarrhea during EF can put elderly patients at risk of postoperative malnutrition and a poor prognosis after esophagectomy.

Role of probiotics in preventing Clostridioides difficile infection in older adults: an integrative review

Clostridioides difficile infection (CDI) is the leading cause of healthcare-associated diarrhea. This infection can particularly affect older adults, the most susceptible to CDI. Currently, the standard therapeutic measure is antibiotic therapy, which in turn increases the risk of recurrence of the infection by its collateral damage to the patient's microbiota. Probiotics are live microorganisms capable of maintaining balance in the intestinal microbiota. This study aims to perform an integrative review of the protective benefit of probiotics in CDI and diarrhea associated with C. difficile. The PubMed, Scopus, and Web of Science databases, the 10-year time cutoff, and the Prism Flow diagram were used for data collection. We observed no consensus among the studies; however, three of the seven evaluated studies demonstrated that the use of probiotics in older adults could contribute to reducing the incidence of hospital-onset CDI. We also found that the studies evaluated a wide variety of microorganisms, particularly Saccharomyces boulardii, associated with beneficial effects. More research is needed to understand the successful use of probiotics in the prevention of CDI in hospitalized older adults receiving antibiotics.

Clinical efficacy of probiotics in prevention of infectious diseases among hospitalized patients in ICU and non-ICU wards in clinical randomized trials: A systematic review

Background and Aims

The present study aimed to review probiotics' clinical efficacy in preventing infectious diseases among hospitalized patients in ICU and non-ICU wards.

Methods

A search of Medline, EMBASE, The Cochrane Library, Science Direct, Open Grey, and Google Scholar was conducted for eligible publications from 2002 to 2020 following the requirements outlined in the PRISMA guideline. The search strategy was based on the combination of the following terms: "probiotics," "prebiotics," "synbiotics," and "cross-infection." The logical operators "AND" (or the equivalent operator for the databases) and "OR" (e.g., probiotics OR prebiotics OR synbiotics) were used.

Results

The results indicated that the probiotic consumption caused a significant reduction in antibiotic-associated diarrhea (AAD) and Clostridioides difficile infection (CDI) in 2/8 randomized clinical trials (RCTs) investigating AAD/CDI. Also, 5/12 clinical trials highlighted the considerable effects of probiotics on the reduction or prevention of ventilator associated pneumoniae (VAP), so the mean prevalence of VAP was lower in the probiotic group than in the placebo group. The total rate of nosocomial infections among preterm infants was nonsignificantly higher in the probiotic group compared to the control group.

Conclusion

This systematic review shows that the administration of probiotics has moderate preventive or mitigating effects on the occurrence of VAP in ICU patients, CDI, AAD, and nosocomial infections among children. Consequently, applying antibiotics along with the proper probiotic species can be advantageous.

Gut microbiota diversity of hospitalized older adult patients with and without antibiotic-associated diarrhea

BACKGROUND

The incidence of antibiotic-related diarrhea (AAD) is high in older adults.

AIM

To examine the gut microbiota changes in older adults who received antibiotics to identify the microbial signatures associated with antibiotic use and AAD.

METHODS

A nested prospective observational cohort study was conducted between December 2019 and June 2021 in patients ≥ 65 years old at Huashan Hospital affiliated with Fudan University. The patients were grouped as antibiotic-treated (HA group) and no antibiotics (HC group); the HA group was subdivided as with vs. without AAD. Fecal samples were collected at admission (i.e., before eventual antibiotics) and after 7 days.

RESULT

Thirty-eight and 19 participants were included in the HA and HC groups. There were significant differences in gut microbiota between the HA after antibiotics vs. HC groups, with a higher Firmicutes/Bacteroidetes ratio. Before antibiotics in the HA group, the relative abundances of Akkermansia and Alistipes were lower in the AAD subgroup than the no-AAD subgroup, while the relative abundance of Actinomyces was higher. After antibiotics in the HA group, specific bacterial species were decreased in the AAD subgroup compared with the no-AAD subgroup. Among HA participants without probiotics, the abundance of Akkermansia in the patients without AAD was higher than in the patients with AAD at baseline (P = 0.007).

CONCLUSION

Patients with or without AAD have different gut microbiota compositions before antibiotics. Antibiotics can lead to dysbiosis, with a decrease in beneficial bacteria and an increase in Enterococcus.

The Role of Probiotics and Their Metabolites in the Treatment of Depression

Depression is a common and complex mental and emotional disorder that causes disability, morbidity, and quite often mortality around the world. Depression is closely related to several physical and metabolic conditions causing metabolic depression. Studies have indicated that there is a relationship between the intestinal microbiota and the brain, known as the gut–brain axis. While this microbiota–gut–brain connection is disturbed, dysfunctions of the brain, immune system, endocrine system, and gastrointestinal tract occur. Numerous studies show that intestinal dysbiosis characterized by abnormal microbiota and dysfunction of the microbiota–gut–brain axis could be a direct cause of mental and emotional disorders. Traditional treatment of depression includes psychotherapy and pharmacotherapy, and it mainly targets the brain. However, restoration of the intestinal microbiota and functions of the gut–brain axis via using probiotics, their metabolites, prebiotics, and healthy diet may alleviate depressive symptoms. Administration of probiotics labeled as psychobiotics and their metabolites as metabiotics, especially as an adjuvant to antidepressants, improves mental disorders. It is a new approach to the prevention, management, and treatment of mental and emotional illnesses, particularly major depressive disorder and metabolic depression. For the effectiveness of antidepressant therapy, psychobiotics should be administered at a dose higher than 1 billion CFU/day for at least 8 weeks.

Effect of Lactobacillus plantarum P9 on defecation, quality of life and gut microbiome in individuals with chronic diarrhoea: Protocol for a randomized, double-blind, placebo-controlled clinical trial

Background

Probiotics may be an ideal choice for these patients, given it can improve the defecation and quality of life of individuals with chronic diarrhoea. However, evidence-based medical research is still limited to support its use as a diarrhoea agent.

Method

A randomized, double-blind, placebo-controlled clinical trial is designed to pinpoint the efficiency and possible action modes of probiotics for chronic diarrhoea. 200 eligible volunteers with chronic diarrhoea are randomly assigned to a probiotic group (orally taking Lactobacillus plantarum p9 probiotics powder) or a placebo group. Except an independent project administrator who will be responsible for unblinding, the other researchers are blinded. Primary outcome is diarrhoea severity score, and secondary outcomes include weekly mean frequency of defecation, weekly mean stool appearance score, weekly mean stool urgency score, emotional state score, gut microbiome, and faecal metabolome. Each outcome measure will be assessed at the timepoints of pre-administration (day 0), administration (day 14 and/or 28), and post-administration (day 42) to identity inter- and intra-groups differences. Adverse events will be recorded to evaluate the safety of L. plantarum p9.

Discussion

The study protocol will provide high-quality evidence for the use of probiotics as a diarrhoea agent when it is strictly conducted out, providing evidence regarding whether and to what extent L. plantarum p9 can improve the defecation and well-being of individuals with chronic diarrhoea.

Trial registration

Chinese Clinical Trial Registry (ChiCTR) (NO. ChiCTR2000038410). Registered on November 22, 2020, https://www.chictr.org.cn/showproj.aspx?proj=56542.

Nutrition, Immunosenescence, and Infectious Disease: An Overview of the Scientific Evidence on Micronutrients and on Modulation of the Gut Microbiota

The immune system is key to host defense against pathogenic organisms. Aging is associated with changes in the immune system, with a decline in protective components (immunosenescence), increasing susceptibility to infectious disease, and a chronic elevation in low-grade inflammation (inflammaging), increasing the risk of multiple noncommunicable diseases. Nutrition is a determinant of immune cell function and of the gut microbiota. In turn, the gut microbiota shapes and controls the immune and inflammatory responses. Many older people show changes in the gut microbiota. Age-related changes in immune competence, low-grade inflammation, and gut dysbiosis may be interlinked and may relate, at least in part, to age-related changes in nutrition. A number of micronutrients (vitamins C, D, and E and zinc and selenium) play roles in supporting the function of many immune cell types. Some trials report that providing these micronutrients as individual supplements can reverse immune deficits in older people and/or in those with insufficient intakes. There is inconsistent evidence that this will reduce the risk or severity of infections including respiratory infections. Probiotic, prebiotic, or synbiotic strategies that modulate the gut microbiota, especially by promoting the colonization of lactobacilli and bifidobacteria, have been demonstrated to modulate some immune and inflammatory biomarkers in older people and, in some cases, to reduce the risk and severity of gastrointestinal and respiratory infections, although, again, the evidence is inconsistent. Further research with well-designed and well-powered trials in at-risk older populations is required to be more certain about the role of micronutrients and of strategies that modify the gut microbiota-host relationship in protecting against infection, especially respiratory infection.

Gastrointestinal Microbiome and Multiple Health Outcomes: Umbrella Review

In recent years, there has been growing concern about the impact of the gastrointestinal microbiome on human health outcomes. To clarify the evidence for a link between the gastrointestinal microbiome and a variety of health outcomes in humans, we conducted an all-encompassing review of meta-analyses and systematic reviews that included 195 meta-analyses containing 950 unique health outcomes. The gastrointestinal microbiome is related to mortality, gastrointestinal disease, immune and metabolic outcomes, neurological and psychiatric outcomes, maternal and infant outcomes, and other outcomes. Existing interventions for intestinal microbiota (such as probiotics, fecal microbiota transplant, etc.) are generally safe and beneficial to a variety of human health outcomes, but the quality of evidence is not high, and more detailed and well-designed randomized controlled trials are necessary.

Early use of probiotics might prevent antibiotic-associated diarrhea in elderly (>65 years): a systematic review and meta-analysis

Background

Antibiotic-associated diarrhea (AAD) is diarrhea associated with consuming antibiotics that cannot be explained by other causes. AAD prolongs admission time and increases mortality and financial costs. Elderly individuals are more prone to receive antibiotic treatment and develop AAD. The finding that living probiotic microorganisms decrease AAD incidence in adults (<65 years) has been clarified. However, it is controversial among elderly individuals.

Methods

We aimed to explore whether probiotics could prevent AAD in elderly individuals. We searched three electronic databases (PubMed, EMBASE, and The Cochrane Library), and two reviewers independently screened and assessed the studies. RevMan5.4 software was used to perform a meta-analysis according to the PRISMA guidelines.

Results

Eight RCTs of 4691 participants were included. We excluded two large studies because probiotics were used 48 hours after the first dose of antibiotics, and there was no effect. Subgroup analysis of 6 RCTs showed that probiotics given within two days of antibiotic treatment produced a lower AAD prevalence rate in elderly individuals.

Conclusion

We recommend that elderly individuals could be routinely distributed probiotics to prevent AAD development when receiving antibiotic treatment.

Trial registration

The review was not registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03257-3.

Probiotics for the prevention of antibiotic-associated diarrhoea: a systematic review and meta-analysis

OBJECTIVE

To evaluate existing evidence for the use of probiotics in preventing antibiotic-associated diarrhoea (AAD) in adults.

DESIGN

Systematic review and meta-analysis of randomised controlled trials (RCTs).

DATA SOURCES

We performed a literature search of the electronic databases CINAHL Plus, EMBASE, MEDLINE (Ovid) and Web of Science from database inception to May 2021 as well as hand searching of trial registries and reference lists of related reviews.

STUDY SELECTION

Two reviewers identified whether RCTs met the following inclusion criteria: adult population to whom antibiotics were administered; a probiotic intervention; a placebo, alternative dose, alternative probiotic strain or no treatment control; and incidence of AAD as the outcome.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently collected data and assessed risk of bias using preconstructed data extraction forms. We used a random effects model for all analyses. Subgroup analyses were performed to evaluate species-specific and dose-specific response.

RESULTS

Forty-two studies (11,305 participants) were included in this review. The pooled analysis suggests that co-administration of probiotics with antibiotics reduces the risk of AAD in adults by 37% (risk ratio (RR)=0.63 (95% CI 0.54 to 0.73), p<0.00001). The overall quality of the evidence using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) criteria was found to be moderate. In subgroup analyses, high dose compared with low dose of the same probiotic demonstrated a positive protective effect (RR 0.54 (95% CI 0.38 to 0.76), p<0.01), and only certain species, mainly of the lactobacillus and bifidobacteria genera, were found to be effective. Studies with a low baseline AAD risk did not show any difference in risk but studies with moderate or high baseline AAD risk demonstrated a significant risk reduction.

CONCLUSIONS

Probiotics are effective for preventing AAD. Secondary analyses of higher dosages and certain species have shown increased effectiveness. Our results may not be applicable in clinical scenarios of lower baseline AAD risk.

Is Regular Probiotic Practice Safe for Management of Sepsis?

For decades, the gut has been thought to play an important role in sepsis pathogenesis. Sepsis is a serious life-threatening, chronic condition of an infection caused by dysregulated host immune response in most of the intensive care unit patients. Probiotics have dual roles in polymicrobial sepsis i.e. probiotics may induce sepsis in many cases and may prevent its prognosis in many cases. Experimental evidence from both pre-clinical and clinical studies have demonstrated that probiotic therapy ameliorates various inflammatory mediators such as tumor necrosis factor, interleukin-10 (IL-10), IL-6, etc., in septicemia. In addition, probiotic use was also found to reduce the severity of pathological conditions associated with irritable bowel disorder and prevent development of endocarditis in septicemia. On contrary, probiotic therapy in neonatal and athymic adult mice fail to provide any beneficial effects on mortality and sepsis-induced inflammation. Importantly, in few clinical trials probiotic use was found to aggravate sepsis by promoting inflammatory cascade rather than suppressing it. This review discusses various studies regarding the beneficial or harmful effects associated with probiotic therapy in sepsis.

The Prevalence of Gastrointestinal Symptoms, Abnormal Liver Function, Digestive System Disease and Liver Disease in COVID-19 Infection: A Systematic Review and Meta-Analysis

BACKGROUND

The worldwide outbreak of COVID-19 infected millions of people. Some patients had gastrointestinal (GI) symptoms, abnormal liver function, digestive system disease and liver disease.

AIM

To investigate the prevalence of GI symptoms, abnormal liver function, digestive system disease and liver disease in patients with COVID-19 by a systematic review and meta-analysis.

METHODS

We searched PubMed, Ovid Embase, Medline, and 2 Chinese databases. Primary outcomes were the prevalence of GI symptoms, abnormal liver function, digestive system disease, and liver disease. Different studies were included in different subset analysis. These outcomes were estimated with proportions, odds ratio, 95% confidence interval (CI) and P-value by Stata SE 15.1.

RESULTS

Thirty-one studies involving 4682 patients were included. The most significant GI symptoms were diarrhea (0.08, 95% CI: 0.06-0.11) and anorexia (0.17, 95% CI: 0.06-0.27). The most significant abnormal liver function was increased alanine aminotransferase (ALT) (0.25, 95% CI: 0.16-0.33). A total of 5% of the patients had digestive system disease (95% CI: 0.02-0.08). A total of 3% of the patients had liver disease (95% CI: 0.02-0.05). The prevalence of nausea and vomiting, diarrhea, abnormal liver function, digestive system disease, and liver disease was higher in Wuhan group. The prevalence of diarrhea was higher in non-China group. Patients in severe/intensive care unit group were more likely to have diarrhea, anorexia, abdominal pain increased aspartate aminotransferase, and increased ALT.

CONCLUSION

The most significant GI symptoms were anorexia and diarrhea. The most significant abnormal liver function was increased ALT. Severe patients were more likely to have GI symptoms and abnormal liver function.

The prospects of employing probiotics in combating COVID-19

Unanticipated pathogenic risk and emerging transmittable diseases can result from interspecies exchanges of viruses among animals and humans. The emergence of the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causing coronavirus disease-19 (COVID-19) pandemic has recently exemplified this mechanism. Cough, fever, fatigue, headache, sputum production, hemoptysis, dyspnea, diarrhea, and gastrointestinal disorders are the characteristic features of the disease. The most prevalent and serious manifestation of the infection tends to be pneumonia. The new strains of SARS-CoV-2 with more infectivity have been emerging at regular intervals. There is currently no World Health Organization-approved particular drug for COVID-19. Besides, developing novel antivirals would take much time. Thus, repurposing the application of natural products can provide alternatives and can facilitate medication against COVID-19 as well as can slow down the aggressive progression of the disease before the arrival of approved drugs. Probiotics have long been known for their positive effects on the gut microbiome and impact on immune responses. Particularly, their involvement against viral diseases, especially those of the upper and lower respiratory tract, is of current interest for their prospective application against COVID-19. In this review, we comprehensively address the mode of action of probiotics and their possible intervention against coronavirus diseases correlating with their efficacy against viral diseases. In this regard, we explored recently published relevant research and review articles in MEDLINE/PubMed related to COVID-19 and the effects of probiotics on viral infections.

Probiotics Modulate Intestinal Motility and Inflammation in Zebrafish Models

This study was aimed to assess effects of three strains of probiotics Lactobacillus acidophilus NCFM, Lactobacillus rhamnosus HN001, and Bifidobacterium animalis subsp. lactis Bi-07 on the intestinal motility and inflammation in the zebrafish models. The intestinal motility model was established using 5 days postfertilization (dpf) zebrafish administered with a fluorescent dye Nile red at 10 ng/mL for 16 h, followed by probiotics treatment for 24 h and the intestinal motility was inversely proportional to the intestinal fluorescence intensity that was quantitatively measured by image analysis. The intestinal inflammation was induced by treating 3 dpf neutrophil fluorescent zebrafish with 0.0125% of trinitrobenzenesulfonic acid for 48 h. Probiotics were administered at low, moderate, and high concentrations determined based on maximum tolerable concentration through soaking. All three strains of probiotics promoted intestinal movement, of which B. animalis subsp. lactis Bi-07 was most potent at lower concentrations. L. rhamnosus HN001 and B. animalis subsp. lactis Bi-07 had the therapeutic effects on the intestinal inflammation and the inflammation-associated mucosal damage recovery. The anti-inflammatory mechanisms of L. rhamnosus HN001 was related to both reduce inflammatory factor interleukin-6 (IL-6) and restored tissue repair factor transforming growth factor-β-1 (TGFβ-1); whereas B. animalis subsp. lactis Bi-07 was probably only associated with TGFβ-1 elevation. Using larval zebrafish models for probiotics screening and assessment would speed up product research and development and improve products' efficacy and quality.

Gut microbiota and old age: Modulating factors and interventions for healthy longevity

Our gut microbiota is a complex and dynamic ecosystem with a paramount role in shaping our metabolic and immunological functions. Recent research suggests that aging may negatively affect the composition, diversity, and function of our microbiota mainly due to alterations in diet and immunologic reactivity (i.e. immunosenescence), and increased incidence of certain diseases and, therefore, increased exposure to certain medication (e.g. antibiotics, proton pump inhibitors). In turn, this aging-related gut dysbiosis may contribute to the initiation and/or progress of other metabolic diseases, and consequently, to a decrease in healthy longevity. On the positive side, promising therapeutic interventions, such as diet supplementation with prebiotics, probiotics and synbiotics, or fecal microbiota transplantation, aimed to counteract these aging-related deleterious consequences, could improve our health, and extend our healthy lifespan. In this context, the current review aims to assess the latest progress in identifying the key elements affecting the gut microbiota of the older adults and their mechanism of action, and the effectiveness of the therapeutic interventions aimed at restoring the diversity and healthy functions of the gut microbiota in older individuals.

Prevention of Clostridium difficile Infection and Associated Diarrhea: An Unsolved Problem

For many years, it has been known that Clostridium difficile (CD) is the primary cause of health-care-associated infectious diarrhea, afflicting approximately 1% of hospitalized patients. CD may be simply carried or lead to a mild disease, but in a relevant number of patients, it can cause a very severe, potentially fatal, disease. In this narrative review, the present possibilities of CD infection (CDI) prevention will be discussed. Interventions usually recommended for infection control and prevention can be effective in reducing CDI incidence. However, in order to overcome limitations of these measures and reduce the risk of new CDI episodes, novel strategies have been developed. As most of the cases of CDI follow antibiotic use, attempts to rationalize antibiotic prescriptions have been implemented. Moreover, to reconstitute normal gut microbiota composition and suppress CD colonization in patients given antimicrobial drugs, administration of probiotics has been suggested. Finally, active and passive immunization has been studied. Vaccines containing inactivated CD toxins or components of CD spores have been studied. Passive immunization with monoclonal antibodies against CD toxins or the administration of hyperimmune whey derived from colostrum or breast milk from immunized cows has been tried. However, most advanced methods have significant limitations as they cannot prevent colonization and development of primary CDI. Only the availability of vaccines able to face these problems can allow a resolutive approach to the total burden due to this pathogen.

When to use probiotics in luminal gastrointestinal disorders?

PURPOSE OF REVIEW

With the growing popularity and commercialization of probiotics, it is important to understand the implications of existing randomized controlled trials and their applicability in the clinical setting to treat luminal gastrointestinal diseases.

RECENT FINDINGS

Probiotics may be useful in the prevention of antibiotic-associated diarrhea, prevention of Clostridioides difficile infection and eradication of Helicobacter pylori. Some evidence supports the use of probiotics in the treatment of ulcerative colitis, prevention and treatment of pouchitis and irritable bowel syndrome. Caution has to be exercised in immunocompromised and critically ill individuals. New society guidelines do not encourage probiotic use in gastrointestinal disorders with the exception of premature infants to prevent necrotizing enterocolitis.

SUMMARY

Despite burgeoning body of literature and wide acceptance by the public, a thorough understanding of efficacy and safety of probiotics is lacking. Uniform dosage, standardized clinical end points, personalization based on host microbial profile and longer duration of follow-up on the research front may help in the future in appropriate positioning of probiotics in health and disease.

Flavonoid-Rich Orange Juice Intake and Altered Gut Microbiome in Young Adults with Depressive Symptom: A Randomized Controlled Study

Depression is not just a general mental health problem but a serious medical illness that can worsen without treatment. The gut microbiome plays a major role in the two-way communication system between the intestines and brain. The current study examined the effects of flavonoids on depression by observing the changes in the gut microbiome and depressive symptoms of young participants consuming flavonoid-rich orange juice. The depressive symptom was assessed using the Center for Epidemiological Studies Depression Scale (CES-D), a psychiatric screening tool used to detect preexisting mental disorders. The study population was randomly divided into two groups: the flavonoid-rich orange juice (FR) and an equicaloric flavonoid-low orange cordial (FL) group. For 8 weeks, participants consumed FR (serving a daily 380 mL, 600 ± 5.4 mg flavonoids) or FL (serving a daily 380 mL, 108 ± 2.6 mg flavonoids). In total, 80 fecal samples from 40 participants (mean age, 21.83 years) were sequenced. Regarding depression, we observed positive correlations between brain-derived neurotrophic factor (BDNF) and the Lachnospiraceae family (Lachnospiraceae_uc and Murimonas) before flavonoid orange juice treatment. Most notably, the abundance of the Lachnospiraceae family (Lachnospiraceae_uc, Eubacterium_g4, Roseburia_uc, Coprococcus_g2_uc, Agathobacter_uc) increased after FR treatment compared to that after FL treatment. We also validated the presence of unclassified Lachnospiraceae through sensitive real-time quantitative polymerase chain reaction using stool samples from participants before and after flavonoid treatment. Our results provide novel interventional evidence that alteration in the microbiome due to flavonoid treatment is related to a potential improvement in depression in young adults.

Nutrition, immunity and COVID-19

The immune system protects the host from pathogenic organisms (bacteria, viruses, fungi, parasites). To deal with this array of threats, the immune system has evolved to include a myriad of specialised cell types, communicating molecules and functional responses. The immune system is always active, carrying out surveillance, but its activity is enhanced if an individual becomes infected. This heightened activity is accompanied by an increased rate of metabolism, requiring energy sources, substrates for biosynthesis and regulatory molecules, which are all ultimately derived from the diet. A number of vitamins (A, B₆, B₁₂, folate, C, D and E) and trace elements (zinc, copper, selenium, iron) have been demonstrated to have key roles in supporting the human immune system and reducing risk of infections. Other essential nutrients including other vitamins and trace elements, amino acids and fatty acids are also important. Each of the nutrients named above has roles in supporting antibacterial and antiviral defence, but zinc and selenium seem to be particularly important for the latter. It would seem prudent for individuals to consume sufficient amounts of essential nutrients to support their immune system to help them deal with pathogens should they become infected. The gut microbiota plays a role in educating and regulating the immune system. Gut dysbiosis is a feature of disease including many infectious diseases and has been described in COVID-19. Dietary approaches to achieve a healthy microbiota can also benefit the immune system. Severe infection of the respiratory epithelium can lead to acute respiratory distress syndrome (ARDS), characterised by excessive and damaging host inflammation, termed a cytokine storm. This is seen in cases of severe COVID-19. There is evidence from ARDS in other settings that the cytokine storm can be controlled by n-3 fatty acids, possibly through their metabolism to specialised pro-resolving mediators.

The Gut Microbiota and Its Implication in the Development of Atherosclerosis and Related Cardiovascular Diseases

The importance of gut microbiota in health and disease is being highlighted by numerous research groups worldwide. Atherosclerosis, the leading cause of heart disease and stroke, is responsible for about 50% of all cardiovascular deaths. Recently, gut dysbiosis has been identified as a remarkable factor to be considered in the pathogenesis of cardiovascular diseases (CVDs). In this review, we briefly discuss how external factors such as dietary and physical activity habits influence host-microbiota and atherogenesis, the potential mechanisms of the influence of gut microbiota in host blood pressure and the alterations in the prevalence of those bacterial genera affecting vascular tone and the development of hypertension. We will also be examining the microbiota as a therapeutic target in the prevention of CVDs and the beneficial mechanisms of probiotic administration related to cardiovascular risks. All these new insights might lead to novel analysis and CVD therapeutics based on the microbiota.

Microbiota modulation-based therapy for luminal GI disorders: current applications of probiotics and fecal microbiota transplantation

Introduction: Alteration in the intestinal microbiota also termed as intestinal dysbiosis has been demonstrated in numerous gastrointestinal disorders linked to aberrant immune processes, acquisition of pathogenic organisms and often administration of antibiotics. Restoration of microbiota through probiotics and fecal microbiota transplantation (FMT) has gained tremendous popularity among researchers in the prevention and treatment of gastrointestinal diseases.Areas covered: In this review, studies testing the safety and efficacy of probiotics and FMT for the treatment of various infectious and inflammatory luminal gastrointestinal diseases are reviewed. Randomized control studies are given priority while important uncontrolled studies are also highlighted.Expert opinion: Probiotics have demonstrated efficacy in the prevention of antibiotic-associated diarrhea and in the eradication of Helicobacter pylori infection. Their utility in the primary and secondary prevention of Clostridioides difficile infection is debatable. The future of medicine should bring forth a personalized approach to probiotic use. FMT has revolutionized the treatment of recurrent CDI as well as severe and fulminant CDI. At the same time, it has galvanized gut microbiota research in the last decade. While FMT in ulcerative colitis appears promising, further studies on the durability and long-term safety are needed before it can be recommended in clinical practice.

Probiotic Yogurt for the Prevention of Antibiotic-associated Diarrhea in Adults: A Randomized Double-blind Placebo-controlled Trial

GOAL

To evaluate the effect of yogurt supplemented with probiotic bacteria on the prevention of antibiotic-associated diarrhea (AAD) in hospitalized patients.

BACKGROUND

Diarrhea following antibiotic administration is a frequent clinical problem. The usefulness of probiotics for the prevention of AAD in the hospitalized adult population remains unclear.

STUDY

A randomized, double-blind, placebo-controlled clinical trial was conducted in hospitalized patients who started antibiotic treatment. Patients were randomized (2:2:1) to receive a daily amount of 200 mL of placebo-yogurt (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus), 200 mL of probiotic yogurt (previous plus Lactobacillus acidophilus La-5, Bifidobacterium animalis subsp. lactis Bb-12 and Lactobacillus casei subsp. casei Lc-01 or no yogurt (unblinded control) within 48 hours of beginning the antibiotic therapy and up to 5 days after stopping the antibiotic. Patients were followed up with for 1 month to determine occurrence of diarrhea.

RESULTS

We included 314 patients, mean age 76 years. The rate of diarrhea was 23.0% in the probiotic group versus 17.6% in the placebo group, absolute risk reduction -5.35% (95% confidence interval, -15.4% to 4.7%; P=0.30). Rate of diarrhea was similar in the unblinded external control and in the blinded study groups combined (20.9% vs. 20.2% respectively; P=0.91). There was no difference in the duration of diarrhea, maximum number of bowel movements or prolonged admission because of diarrhea among the groups. All-cause mortality did not differ between groups.

CONCLUSIONS

The combined probiotic strains LA-5, BB-12, and LC-01 do not have an effect in the prevention of AAD in hospitalized patients.

Rescue fecal microbiota transplantation for antibiotic-associated diarrhea in critically ill patients

BACKGROUND

Antibiotic-associated diarrhea (AAD) is a risk factor for exacerbating the outcome of critically ill patients. Dysbiosis induced by the exposure to antibiotics reveals the potential therapeutic role of fecal microbiota transplantation (FMT) in these patients. Herein, we aimed to evaluate the safety and potential benefit of rescue FMT for AAD in critically ill patients.

METHODS

A series of critically ill patients with AAD received rescue FMT from Chinese fmtBank, from September 2015 to February 2019. Adverse events (AEs) and rescue FMT success which focused on the improvement of abdominal symptoms and post-ICU survival rate during a minimum of 12 weeks follow-up were assessed.

RESULTS

Twenty critically ill patients with AAD underwent rescue FMT, and 18 of them were included for analysis. The mean of Acute Physiology and Chronic Health Evaluation (APACHE) II scores at intensive care unit (ICU) admission was 21.7 ± 8.3 (range 11-37). Thirteen patients received FMT through nasojejunal tube, four through gastroscopy, and one through enema. Patients were treated with four (4.2 ± 2.1, range 2-9) types of antibiotics before and during the onset of AAD. 38.9% (7/18) of patients had FMT-related AEs during follow-up, including increased diarrhea frequency, abdominal pain, increased serum amylase, and fever. Eight deaths unrelated to FMT occurred during follow-up. One hundred percent (2/2) of abdominal pain, 86.7% (13/15) of diarrhea, 69.2% (9/13) of abdominal distention, and 50% (1/2) of hematochezia were improved after FMT. 44.4% (8/18) of patients recovered from abdominal symptoms without recurrence and survived for a minimum of 12 weeks after being discharged from ICU.

CONCLUSION

In this case series studying the use of FMT in critically ill patients with AAD, good clinical outcomes without infectious complications were observed. These findings could potentially encourage researchers to set up new clinical trials that will provide more insight into the potential benefit and safety of the procedure in the ICU.

TRIAL REGISTRATION

ClinicalTrials.gov, Number NCT03895593 . Registered 29 March 2019 (retrospectively registered).

Relationship between the gut microbiome and brain function

It has become increasingly evident in recent years that the gut microbiome and the brain communicate in a bidirectional manner, with each possibly affecting the other's functions. Substantial research has aimed to understand the mechanisms of this interaction and to outline strategies for preventing or treating nervous system-related disturbances. This review explores the evidence demonstrating how the gut microbiome may affect brain function in adults, thereby having an impact on stress, anxiety, depression, and cognition. In vitro, in vivo, and human studies reporting an association between a change in the gut microbiome and functional changes in the brain are highlighted, as are studies outlining the mechanisms by which the brain affects the microbiome and the gastrointestinal tract. Possible modes of action to explain how the gut microbiome and the brain functionally affect each other are proposed. Supplemental probiotics to combat brain-related dysfunction offer a promising approach, provided future research elucidates their mode of action and possible side effects. Further studies are warranted to establish how pre- and probiotic interventions may help to balance brain function in healthy and diseased individuals.

Probiotics in the next-generation sequencing era

Technological developments, including massively parallel DNA sequencing, gnotobiotics, metabolomics, RNA sequencing and culturomics, have markedly propelled the field of microbiome research in recent years. These methodologies can be harnessed to improve our in-depth mechanistic understanding of basic concepts related to consumption of probiotics, including their rules of engagement with the indigenous microbiome and impacts on the human host. We have recently demonstrated that even during probiotic supplementation, resident gut bacteria in a subset of individuals resist the mucosal presence of probiotic strains, limiting their modulatory effect on the microbiome and on the host gut transcriptional landscape. Resistance is partly alleviated by antibiotics treatment, which enables probiotics to interact with the host at the gut mucosal interface, although rather than promoting reconstitution of the indigenous microbiome and of the host transcriptional profile, they inhibit these components from returning to their naïve pre-antibiotic configurations. In this commentary, we discuss our findings in the context of previous and recent works, and suggest that incorporating the state-of-the-art methods currently utilized in microbiome research into the field of probiotics may lead to improved understanding of their mechanisms of activity, as well as their efficacy and long-term safety.

The Contribution of Complementary and Alternative Medicine to Reduce Antibiotic Use: A Narrative Review of Health Concepts, Prevention, and Treatment Strategies

AIM

The aim of this narrative review was to explore the potential contributions of CAM to reduce antibiotic use.

METHODS

We searched PubMed, Embase, and Cochrane Database of Systematic Reviews with a specific, limited set of search terms and collected input from a group of expert CAM researchers to answer the question: What is known about the contribution of CAM health and health promotion concepts, infection prevention, and infection treatment strategies to reduce antibiotic use? Results. The worldview-related CAM health concepts enable health promotion oriented infection prevention and treatment aimed at strengthening or supporting the self-regulating ability of the human organism to cope with diseases. There is some evidence that the CAM concepts of health (promotion) are in agreement with current conceptualization of health and that doctors who practice both CAM and conventional medicine prescribe less antibiotics, although selection bias of the presented studies cannot be ruled out. There is some evidence that prevention and some treatment strategies are effective and safe. Many CAM treatment strategies are promising but overall lack high quality evidence.

CONCLUSIONS

CAM prevention and treatment strategies may contribute to reducing antibiotic use, but more rigorous research is necessary to provide high quality evidence of (cost-)effectiveness.

Gastrointestinal symptom improvement from fiber, STW 5, peppermint oil, and probiotics use-Results from an online survey

OBJECTIVES

Several common supplements are used by a significant number of patients affected by gastrointestinal (GI) disorders to improve symptoms and quality of life. We investigated the impact of GI symptom improvement with the use of fiber, STW 5, probiotics, and peppermint oil in relation to overall GI pain and quality of life via an online survey.

DESIGN

We used a cross-sectional, descriptive, correlation design. A Qualtrics online survey was utilized to collect data from January to June 2013 through various websites. Areas evaluated included participant demographics, use of supplements, and gastrointestinal symptom severity.

RESULTS

The rate of supplement use among patients with GI disorders was high (90% in past year) and consultation with healthcare providers was reported by 80%. Participants who completed the survey (n = 68) reported a strong correlation between GI symptom severity and overall quality of life (r² = 0.8682, p < 0.001). The use of fiber improved GI symptom severity while both STW 5 and probiotics were linked to specific improvements.

CONCLUSIONS

Persons with chronic GI disorders often choose the complementary use of common supplements to mitigate GI symptoms and consult with their healthcare providers frequently. The use of STW 5 and probiotics specifically is linked to overall reduction in GI symptoms and improvement of quality of life.

Probiotics in Gastroenterology: How Pro Is the Evidence in Adults?

Probiotic usage has become popular with both medical practitioners and the community in general; patients commonly seek advice regarding what, if any, such preparation would be useful for their own diseases. Since such advice should be evidence-based, identified randomized clinical trials (RCTs) for a number of gastrointestinal conditions were reviewed; the data were organized by individual probiotic genera/species. Only trials in adults were considered. Most of the identified RCTs were small and low-quality, so any conclusions to be drawn will be limited at least by methodologic problems. Using the GRADE system to consider the reliability of the evidence generated from these RCTs, it did appear that the use of fecal microbial transplantation to treat recurrent Clostridium difficile infection is well justified. Given the methodologic issues, there was moderately good evidence for preventing antibiotic-associated diarrhea with Lactobacillus, Bifidobacterium, Streptococcus, or Saccharomyces boulardii and for using Lactobacillus, Bifidobacterium, or Saccharomyces as adjunct therapy in the treatment of Helicobacter pylori. There were other conditions for which some supportive evidence was available. These conditions include VSL#3 for maintaining remissions in patients with pouchitis or treating active ulcerative colitis (UC), fecal microbial transplantation for treating active UC, Bifidobacterium for treating patients with UC in remission, Lactobacillus in patients with painful diverticulosis, a variety of probiotics (Lactobacillus, Bifidobacterium, Streptococcus, or VSL#3) in patients with minimal hepatic encephalopathy, and providing synbiotics to patients postoperatively after liver transplantation. Unfortunately, other limitations in the evidence made it very likely that future research will have an effect on the estimated benefit; these interventions cannot yet be recommended for routine use.

Feasibility of a Lactobacillus casei Drink in the Intensive Care Unit for Prevention of Antibiotic Associated Diarrhea and Clostridium difficile

Background: Over 70% of patients are prescribed antibiotics during their intensive care (ICU) admission. The gut microbiome is dramatically altered early in an ICU stay, increasing the risk for antibiotic associated diarrhea (AAD) and Clostridium difficile infections (CDI). Evidence suggests that some probiotics are effective in the primary prevention of AAD and CDI. Aim: To demonstrate safety and feasibility of a probiotic drink in ICU patients. Methods: ICU patients initiated on antibiotics were recruited, and matched with contemporary controls. Study patients received two bottles daily of a drink containing 10 billion Lactobacillus casei which was bolused via feeding tube. Tolerance to probiotics and enteral nutrition, development of adverse events, and incidence of AAD was recorded. CDI rates were followed for 30 days post antibiotic treatment. Results: Thirty-two patients participated in the trial. There were no serious adverse events in the probiotic group, compared to three in the control group. AAD was documented in 12.5% of the probiotic group and 31.3% in the control group. One patient in the probiotic group developed CDI compared to three in the control group. Discussion: A probiotic containing drink can safely be delivered via feeding tube and should be considered as a preventative measure for AAD and CDI in ICU.

Reclamation of Herb Residues Using Probiotics and Their Therapeutic Effect on Diarrhea

Residues from herbal medicine processing in pharmaceutical plants create a large amount of waste (herb residues), which consists mainly of environmental pollution and medicinal waste. In order to resolve this problem, probiotics of Bacillus (B.) subtilis, Aspergillus (A.) oryzae, and Lactobacillus (L.) plantarum M3 are selected to reuse herb residue of Jianweixiaoshi tablets (JT), and an antibiotic-associated diarrhea (AAD) mouse model was established to evaluate the therapeutic effects of the herb residue fermentation supernatant. Our results indicated that the fermentation supernatant had scavenged 77.8% of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 78% of O₂^•−, 36.7% of ^•OH, 39% of Fe²⁺ chelation, and 716 mg/L reducing power. The inhibition zones for Salmonella (S.) typhimurium, S. enteritidis, Shigella (Sh.) flexneri, Escherichia (E.) coli, Listeria (L.) monocytogenes, Sh. dysenteriae 301, and Staphylococcus (S.) aureus were 17, 14, 19, 18, 20, 19, and 20 mm, respectively. The in vivo results indicated that the fermentation supernatant resulted in a high diarrhea inhibition rate (56%, p < 0.05), greatly enhanced the disruption of bacterial diversity caused by antibiotics, and restored the dominant position of L. johnsonii in the treatment and recovery stages. Therefore, the combination of the herb residue and probiotics suggests a potential to explore conversion of these materials for the possible development of therapies for AAD.

Comparative efficacy and tolerability of probiotics for antibiotic-associated diarrhea: Systematic review with network meta-analysis

Background

Probiotics are commonly used for the prevention of antibiotic-associated diarrhea (AAD). However, the optimum regimen remains controversial.

Objective

The objective of this article is to compare and rank the relative efficacy and tolerability among all available probiotic agents for AAD through a network meta-analysis.

Methods

Eligible studies were identified by searching PubMed, Embase, Medline, Cochrane library and Web of Science for randomized controlled trials (RCTs) that examined the efficacy of probiotic therapy for AAD. A random-effects model was applied within a frequentist framework. Quality of evidence was performed by the GRADE approach. The project was prospectively registered with PROSPERO (CRD 42016050776).

Results

Fifty-one articles (60 comparisons, 9569 participants), including 10 probiotic interventions, were identified. Lactobacillus rhamnosus GG (LGG) had the highest probability of being ranked best both in effectiveness (odds ratio (OR), 95% confidence interval (CI) = 0.28 (0.17, 0.47)) and tolerance (0.44 (0.23, 0.84)) on prevention of AAD. With regard to reducing Clostridium difficile infection rate, Lactobacillus casei (L. casei) was considered better efficacy (0.04 (0.00, 0.77)) and medium tolerance (0.56 (0.19, 1.66)). Strain combination reported no superiority over single strain in either efficacy or tolerability.

Conclusions

LGG is probably the best option to consider when AAD is indicated. L. casei appears to be the most efficacious choice when associated with severe C. difficile-related cases.

Randomized, Controlled, Crossover trial of Prevention of Clindamycin-Induced Gastrointestinal Signs Using a Synbiotic in Healthy Research Cats

Background

Synbiotics often are prescribed to limit antibiotic‐associated gastrointestinal signs (AAGS) in cats, but data to support this recommendation are lacking.

Objective

To determine whether synbiotic co‐administration mitigates AAGS in healthy research cats treated with clindamycin.

Animals

16 healthy research cats.

Methods

A randomized, double‐blinded, placebo‐controlled, 2‐way, 2‐period, crossover study with a 6‐week washout was performed. Each study period consisted of a 1‐week baseline and a 3‐week treatment period. Cats received 75 mg clindamycin with food once daily for 3 weeks, followed 1 hour later by either 2 capsules of a synbiotic or placebo. Food consumption, vomiting, fecal score, and completion of treatment were compared using repeated measures split plot or crossover designs with covariates, with P < 0.05 considered significant.

Results

Cats that received the synbiotic were more likely to complete treatment in period 1 (100% vs. 50%, P = 0.04). Cats vomited less when receiving the synbiotic but this was not significant, but there were significant period effects (F‐value = 11.4, P < 0.01). Cats had higher food intake while receiving the synbiotic (F‐value = 31.1, P < 0.01) despite period effects (F‐value = 8.6, P < 0.01). There was no significant effect of treatment on fecal scores, which significantly increased over time (F‐value = 17.9, P < 0.01).

Conclusions and Clinical Importance

Administration of a synbiotic 1 hour after clindamycin administration decreased hyporexia and vomiting in healthy cats. Additionally, significant period effects suggest that clinical benefits of synbiotic administration persist for at least 6 weeks after discontinuation, decreasing the severity of AAGS in cats that subsequently received clindamycin with placebo. Unlike in people, synbiotic administration did not decrease antibiotic‐associated diarrhea.

Review of the role of probiotics in gastrointestinal diseases in adults

BACKGROUND

Probiotics may act as biological agents that modify the intestinal microbiota and certain cytokine profiles, which can lead to an improvement in certain gastrointestinal diseases.

OBJECTIVES

To conduct a review of the evidence of the role of probiotics in certain gastrointestinal diseases in adults.

SEARCH METHODS

Review conducted using appropriate descriptors, filters and limits in the PubMed database (MEDLINE).

SELECTION CRITERIA

The MeSH terms used were Probiotics [in the title] AND Gastrointestinal Diseases, with the following limits or filters: Types of study: Systematic Reviews, Meta-Analysis, Guideline, Practice Guideline, Consensus Development Conference (and Consensus Development Conference NIH), Randomized Controlled Trial, Controlled Clinical Trial and Clinical Trial; age: adults (19 or older); language: English and Spanish; in humans, and with at least one abstract.

DATA COLLECTION AND ANALYSIS

Full texts of all the Systematic Reviews and meta-analyses directly related to the review's objective were obtained, as well as the Randomised Controlled Trials of the studies that were considered relevant and of sufficient quality for this review.

MAIN RESULTS

Certain probiotics, different for each process, have proven to be effective and beneficial in cases of acute infectious diarrhoea, antibiotic-associated diarrhoea, Clostridium difficile-associated diarrhoea, pouchitis and Helicobacter pylori infection eradication.

AUTHORS' CONCLUSIONS

Although some probiotics have not demonstrated any benefit, there are certain gastrointestinal diseases in which the use of probiotics, true biological agents, can be recommended.

Effect of Probiotics on Depression: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

It has been reported that gut probiotics play a major role in the bidirectional communication between the gut and the brain. Probiotics may be essential to people with depression, which remains a global health challenge, as depression is a metabolic brain disorder. However, the efficacy of probiotics for depression is controversial. This study aimed to systematically review the existing evidence on the effect of probiotics-based interventions on depression. Randomized, controlled trials, identified through screening multiple databases and grey literature, were included in the meta-analysis. The meta-analysis was performed using Review Manager 5.3 software using a fixed-effects model. The meta-analysis showed that probiotics significantly decreased the depression scale score (MD (depressive disorder) = −0.30, 95% CI (−0.51–−0.09), p = 0.005) in the subjects. Probiotics had an effect on both the healthy population (MD = −0.25, 95% CI (−0.47–−0.03), p = 0.03) and patients with major depressive disorder (MDD) (MD = −0.73, 95% CI (−1.37–−0.09), p = 0.03). Probiotics had an effect on the population aged under 60 (MD = −0.43, 95% CI (−0.72–−0.13), p = 0.005), while it had no effect on people aged over 65 (MD = −0.18, 95% CI (−0.47–0.11), p = 0.22). This is the first systematic review and meta-analysis with the goal of determining the effect of probiotics on depression. We found that probiotics were associated with a significant reduction in depression, underscoring the need for additional research on this potential preventive strategy for depression.