Effect of Aging on the Composition of Fecal Microbiota in Donors for FMT and Its Impact on Clinical Outcomes

Visceral adiposity in postmenopausal women is associated with a pro-inflammatory gut microbiome and immunogenic metabolic endotoxemia

BACKGROUND

Obesity, and in particular abdominal obesity, is associated with an increased risk of developing a variety of chronic diseases. Obesity, aging, and menopause are each associated with differential shifts in the gut microbiome. Obesity causes chronic low-grade inflammation due to increased lipopolysaccharide (LPS) levels which is termed "metabolic endotoxemia." We examined the association of visceral adiposity tissue (VAT) area, circulating endotoxemia markers, and the gut bacterial microbiome in a cohort of aged postmenopausal women.

METHODS

Fifty postmenopausal women (mean age 78.8 ± 5.3 years) who had existing adipose measurements via dual x-ray absorptiometry (DXA) were selected from the extremes of VAT: n = 25 with low VAT area (45.6 ± 12.5 cm2) and n = 25 with high VAT area (177.5 ± 31.3 cm2). Dietary intake used to estimate the Healthy Eating Index (HEI) score was assessed with a food frequency questionnaire. Plasma LPS, LPS-binding protein (LBP), anti-LPS antibodies, anti-flagellin antibodies, and anti-lipoteichoic acid (LTA) antibodies were measured by ELISA. Metagenomic sequencing was performed on fecal DNA. Female C57BL/6 mice consuming a high-fat or low-fat diet were treated with 0.4 mg/kg diet-derived fecal isolated LPS modeling metabolic endotoxemia, and metabolic outcomes were measured after 6 weeks.

RESULTS

Women in the high VAT group showed increased Proteobacteria abundance and a lower Firmicutes/Bacteroidetes ratio. Plasma LBP concentration was positively associated with VAT area. Plasma anti-LPS, anti-LTA, and anti-flagellin IgA antibodies were significantly correlated with adiposity measurements. Women with high VAT showed significantly elevated LPS-expressing bacteria compared to low VAT women. Gut bacterial species that showed significant associations with both adiposity and inflammation (anti-LPS IgA and LBP) were Proteobacteria (Escherichia coli, Shigella spp., and Klebsiella spp.) and Veillonella atypica. Healthy eating index (HEI) scores negatively correlated with % body fat and anti-LPS IgA antibodies levels. Preclinical murine model showed that high-fat diet-fed mice administered a low-fat diet fecal-derived LPS displayed reduced body weight, decreased % body fat, and improved glucose tolerance test parameters when compared with saline-injected or high-fat diet fecal-derived LPS-treated groups consuming a high-fat diet.

CONCLUSIONS

Increased VAT in postmenopausal women is associated with elevated gut Proteobacteria abundance and immunogenic metabolic endotoxemia markers. Low-fat diet-derived fecal-isolated LPS improved metabolic parameters in high-fat diet-fed mice giving mechanistic insights into potential pro-health signaling mediated by under-acylated LPS isoforms. Video Abstract.

Evaluation of the safety and efficacy of fecal microbiota transplantations in bottlenose dolphins (Tursiops truncatus) using metagenomic sequencing

AIMS

Gastrointestinal disease is a leading cause of morbidity in bottlenose dolphins (Tursiops truncatus) under managed care. Fecal microbiota transplantation (FMT) holds promise as a therapeutic tool to restore gut microbiota without antibiotic use. This prospective clinical study aimed to develop a screening protocol for FMT donors to ensure safety, determine an effective FMT administration protocol for managed dolphins, and evaluate the efficacy of FMTs in four recipient dolphins.

METHODS AND RESULTS

Comprehensive health monitoring was performed on donor and recipient dolphins. Fecal samples were collected before, during, and after FMT therapy. Screening of donor and recipient fecal samples was accomplished by in-house and reference lab diagnostic tests. Shotgun metagenomics was used for sequencing. Following FMT treatment, all four recipient communities experienced engraftment of novel microbial species from donor communities. Engraftment coincided with resolution of clinical signs and a sustained increase in alpha diversity.

CONCLUSION

The donor screening protocol proved to be safe in this study and no adverse effects were observed in four recipient dolphins. Treatment coincided with improvement in clinical signs.

Targeting the blood-brain barrier to delay aging-accompanied neurological diseases by modulating gut microbiota, circadian rhythms, and their interplays

The blood-brain barrier (BBB) impairment plays a crucial role in the pathological processes of aging-accompanied neurological diseases (AAND). Meanwhile, circadian rhythms disruption and gut microbiota dysbiosis are associated with increased morbidity of neurological diseases in the accelerated aging population. Importantly, circadian rhythms disruption and gut microbiota dysbiosis are also known to induce the generation of toxic metabolites and pro-inflammatory cytokines, resulting in disruption of BBB integrity. Collectively, this provides a new perspective for exploring the relationship among circadian rhythms, gut microbes, and the BBB in aging-accompanied neurological diseases. In this review, we focus on recent advances in the interplay between circadian rhythm disturbances and gut microbiota dysbiosis, and their potential roles in the BBB disruption that occurs in AAND. Based on existing literature, we discuss and propose potential mechanisms underlying BBB damage induced by dysregulated circadian rhythms and gut microbiota, which would serve as the basis for developing potential interventions to protect the BBB in the aging population through targeting the BBB by exploiting its links with gut microbiota and circadian rhythms for treating AAND.

Fecal microbiota transplantation treatment of autoimmune-mediated type 1 diabetes: A systematic review

There is a strong link between fecal microbiota and the development of type 1 diabetes. As an emerging therapeutic modality, fecal microbiota transplantation has been shown to be safe and effective in the treatment of many intestinal and extraintestinal diseases. Various studies have found that fecal microbiota transplantation can treat diseases by correcting patients' immune disorders. Besides, many studies have found that fecal microbiota transplantation can improve glycemic control and insulin resistance in diabetic patients. Therefore, this paper reviews the mechanism of action of fecal microbiota transplantation on autoimmune-mediated T1DM and the current research progress, feasibility, and issues that need to be addressed in the future development of fecal microbiota transplantation in the treatment of autoimmune-mediated T1DM.

Emerging Interrelationship Between the Gut Microbiome and Cellular Senescence in the Context of Aging and Disease: Perspectives and Therapeutic Opportunities

The significance of diversity, composition, and functional attributes of the gut microbiota in shaping human health is well recognized. Studies have shown that gut microbiota is closely linked to human aging, and changes in the gut microbiome can predict human survival and longevity. In addition, a causal relationship between gut microbiota dysbiosis and chronic age-related disorders is also becoming apparent. Recent advances in our understanding of the cellular and molecular aspects of biological aging have revealed a cellular senescence-centric view of the aging process. However, the association between the gut microbiome and cellular senescence is only beginning to be understood. The present review provides an integrative view of the evolving relationship between the gut microbiome and cellular senescence in aging and disease. Evidence relating to microbiome-mediated modulation of senescent cells, as well as senescent cells-mediated changes in intestinal homeostasis and diseases, have been discussed. Unanswered questions and future research directions have also been deliberated to truly ascertain the relationship between the gut microbiome and cellular senescence for developing microbiome-based age-delaying and longevity-promoting therapies.

Application of Microbiome Management in Therapy for Clostridioides difficile Infections: From Fecal Microbiota Transplantation to Probiotics to Microbiota-Preserving Antimicrobial Agents

Oral vancomycin and metronidazole, though they are the therapeutic choice for Clostridioides difficile infections (CDIs), also markedly disturb microbiota, leading to a prolonged loss of colonization resistance to C. difficile after therapy; as a result, their use is associated with a high treatment failure rate and high recurrent rate. An alternative for CDIs therapy contains the delivery of beneficial (probiotic) microorganisms into the intestinal tract to restore the microbial balance. Recently, mixture regimens containing Lactobacillus species, Saccharomyces boulardii, or Clostridium butyricum have been extensively studied for the prophylaxis of CDIs. Fecal microbiota transplantation (FMT), the transfer of (processed) fecal material from healthy donors to patients for treating CDIs, combined with vancomycin was recommended as the primary therapy for multiple recurrent CDIs (rCDIs). Either probiotics or FMT have been utilized extensively in preventing or treating CDIs, aiming at less disturbance in the microbiota to prevent rCDIs after therapy cessation. Otherwise, many newly developed therapeutic agents have been developed and aim to preserve microbiota during CDI treatment to prevent disease recurrence and might be useful in clinical patients with rCDIs in the future.

A comprehensive review for gut microbes: technologies, interventions, metabolites and diseases

Gut microbes have attracted much more attentions in the recent decade since their essential roles in the development of metabolic diseases, cancer and neurological diseases. Considerable evidence indicates that the metabolism of gut microbes exert influences on intestinal homeostasis and human diseases. Here, we first reviewed two mainstream sequencing technologies involving 16s rRNA sequencing and metagenomic sequencing for gut microbes, and data analysis methods assessing alpha and beta diversity. Next, we introduced some observational studies reflecting that many factors, such as lifestyle and intake of diets, drugs, contribute to gut microbes' quantity and diversity. Then, metabolites produced by gut microbes were presented to understand that gut microbes exert on host homeostasis in the intestinal epithelium and immune system. Finally, we focused on the molecular mechanism of gut microbes on the occurrence and development of several common diseases. In-depth knowledge of the relationship among interventions, gut microbes and diseases might provide new insights in to disease prevention and treatment.

Research progress on the interaction between circadian clock and early vascular aging

Considerable researches implicate that the circadian clock regulates the responsive rhythms of organs and sets the orderly aging process of cells indirectly. It influences an array of diverse biological process including intestinal flora, peripheral inflammatory responses, and redox homeostasis. People with sleep disoders and other kinds of circadian disruptions are prone to have vascular aging earlier. Meanwhile, those people are always faced with chronic vascular inflammation. It has not been elucidated that the specific mechanism of the interaction between the circadian system and early vascular aging. To explore the biphasic relationship between vascular aging and the circadian system, we summarize what is linking circadian clock with early vascular aging through four major prospect: inflammatory process, oxidative stress response, intestinal flora, and cellular senescence. Meanwhile, we discuss the hypothesis that the deterioration of circadian rhythms may exacerbate the process of early vascular aging, leading to the cardiovascular diseases. It will help us to provide new ideas for understanding the process of vascular aging and exploring the possible ways to design personalized chronotherapies.

Managing the Microbiome: How the Gut Influences Development and Disease

The microbiome lies at the forefront of scientific research, as researchers work to uncover its mysterious influence on human development and disease. This paper reviews how the microbiome is studied, how researchers can improve its study, and what clinical applications microbiome research might yield. For this review, we analyzed studies concerning the role of the microbiome in disease and early development, the common methodologies by which the microbiome is researched in the lab, and modern clinical treatments for dysbiosis and their possible future applications. We found that the gut microbiome is essential for proper development of various physiological systems and that gut dysbiosis is a clear factor in the etiology of various diseases. Furthermore, we found that germ-free animal models and microbiome manipulation techniques are inadequate, reducing the efficacy of microbiome research. Nonetheless, research continues to show the significance of microbiome manipulation in the clinical treatment of disease, having shown great promise in the prevention and treatment of dysbiosis. Though the clinical applications of microbiome manipulation are currently limited, the significance of dysbiosis in the etiology of a wide array of diseases indicates the significance of this research and highlights the need for more effective research methods concerning the microbiome.

Faecal microbiota transplantation for recurrent Clostridioides difficile infection: An updated systematic review and meta-analysis

BACKGROUND

Faecal microbiota transplantation (FMT) is effective for recurrent Clostridioides difficile infection (CDI), but inconsistent effect rates and uncertain evidence levels have warranted caution. To clarify, we aimed to establish the evidence of FMT for recurrent CDI, updated across different delivery methods, treatment regimens, and in comparison with standard antibiotics.

METHODS

In this updated systematic review and meta-analysis, we searched PubMed, Scopus, Embase, Web of Science, Clinical Key, and Svemed+ for FMT literature published in English until November 11, 2019. We included observational and clinical trials with or without antibiotic comparators and excluded studies with below 8 weeks follow-up and fewer than 15 patients. The primary outcome was clinical outcome by week 8. We comprehensively extracted patient and procedural data. In a random-effects meta-analysis, we estimated the clinical effect for repeat or single FMT, different delivery methods, and versus antibiotics. We rated the evidence according to the Cochrane and GRADE methods. The PROSPERO preregistration number is CRD42020158112.

FINDINGS

Of 1816 studies assessed, 45 studies were included. The overall clinical effect week 8 following repeat FMT (24 studies, 1855 patients) was 91% (95% CI: 89-94%, I 2=53%) and 84% (80-88%, I 2=86%) following single FMT (43 studies, 2937 patients). Delivery by lower gastrointestinal endoscopy was superior to all other delivery methods, and repeat FMT significantly increased the treatment effect week 8 (P<0·001). Compared with vancomycin, the number needed to treat (NNT) for repeat FMT was 1·5 (1·3-1·9, P<0·001) and 2.9 (1·5-37·1, P=0·03) for single FMT. Repeat FMT had high quality of evidence.

INTERPRETATION

High-quality evidence supports FMT is effective for recurrent CDI, but its effect varies with the delivery method and the number of administrations. The superior NNT for FMT compared with antibiotics suggests that patients may benefit from advancing FMT to all instances of recurrent CDI.

FUNDING

Innovation Fund Denmark (j.no. 8056-00006B).

Fecal Microbiota Transplantation for the Treatment of Inflammatory Bowel Disease: An Update

Fecal microbiota transplantation (FMT) has successfully been applied for the treatment of recurrent Clostridioides difficile infection (CDI), which has led to studies on its application to other gastrointestinal diseases and extraintestinal diseases associated with gut microbiota dysbiosis. Recently, the results of FMT for patients with inflammatory bowel disease (IBD) have been encouraging. However, studies have not fully clarified the clinical application of this emerging therapy. Here, we aimed to review the current knowledge in this fast-growing field and characterize the effectiveness, safety and mechanisms of FMT for the treatment of IBD patients.

[Updated review of Clostridium difficile infection in elderly]

Clostridium difficile infection is the most common cause of health care-associated diarrhoea, and its incidence increases with age. Clinical challenges, risk of resistance to treatment, risk of recurrence, and treatment responses are different in elderly. The aim of this review is to discuss the updated epidemiology, pathophysiology, diagnosis, and therapeutic management of C. difficile infection in elderly with the available data.

Lessons Learned from Faecal Microbiota Transplantation in Cirrhosis

Purpose of Review

We examine recent developments in the treatment of cirrhosis by gut microbiome manipulation specifically focusing on the phase 1 safety and feasibility trials of faecal microbiota transplantation (FMT). We interrogate the published data so far on its feasibility, safety and efficacy.

Recent Findings

A large number of trials have demonstrated the efficacy of FMT in treating recurrent Clostridium difficile infection which is now considered standard of care. In cirrhosis, FMT is still being evaluated and there are a number of clinical trials underway. There are two phase 1 pilot safety studies that have been published with promising findings. However, the importance of rigorously testing donor stool for the presence of multi-drug resistant species has been highlighted and lessons have been learned.

Summary

For those patients with cirrhosis, replacing an unhealthy gut microbiome with a healthy one offers a promising antibiotic-free treatment that may reduce bacterial translocation and endotoxemia.

Abnormal Intestinal Microbiome in Medical Disorders and Potential Reversibility by Fecal Microbiota Transplantation

Reduction in diversity of the intestinal microbiome (dysbiosis) is being identified in many disease states, and studies are showing important biologic contributions of microbiome to health and disease. Fecal microbiota transplantation (FMT) is being evaluated as a way to reverse dysbiosis in diseases and disorders in an attempt to improve health. The published literature was reviewed to determine the value of FMT in the treatment of medical disorders for which clinical trials have recently been conducted. FMT is effective in treating recurrent C. difficile infection in one or two doses, with many healthy donors providing efficacious fecal-derived products. In inflammatory bowel disease (IBD), FMT may lead to remission in approximately one-third of moderate-to-severe illnesses with one study suggesting that more durable FMT responses may be seen when used once medical remissions have been achieved. Donor products differ in their efficacy in treatment of IBD. Combining donor products has been one way to increase the potential value of FMT in treating chronic disorders. FMT is being explored in a variety of clinical settings affecting different organ systems outside CDI, with positive preliminary signals, in treatment of functional constipation, immunotherapy-induced colitis, neurodegenerative disease, as well as prevention of cancer-related disorders like graft versus host disease and decolonization of patients with recurrent urinary tract infection due to antibiotic-resistant bacteria. Currently, intense research is underway to see how the microbiome products like FMT can be harnessed for health benefits.

Fecal Microbiota Transplantation for Clostridioides Difficile Infection in Patients with Chronic Liver Disease

BACKGROUND

Fecal microbiota transplantation (FMT) is a well-established therapeutic option for patients with antibiotic resistant Clostridioides difficile infection (CDI). However, the efficacy of FMT in patients with chronic liver disease remains elusive.

AIMS

We studied the effect of FMT on chronic liver disease (CLD) patients with CDI at our tertiary medical center.

METHODS

A cohort of all patients who received FMT from December 2012 to May 2014 for refractory or recurrent CDI was identified. Patients were monitored for a year after FMT. Descriptive analysis was conducted to compare the effect of FMT in patients with and without CLD.

RESULTS

A total of 201 patients with CDI received FMT, 14 of which had a history of CLD. Nine of these patients exhibited cirrhosis of the liver with a mean Child-Turcotte-Pugh score of 8. CDI development in these patients was associated with recent exposure to antibiotics and was observed to be significantly different between both groups (17% of CLD patients vs. 58% in the general cohort, p = 0.01). Four patients with CLD received >1 FMT, of which 2 did not respond to treatment. There was no significant difference between patients with liver disease and the rest of the cohort with regard to FMT response (12/14 (87%) vs. 164/187 (88%), p = 0.01). Four patients with CLD received >1 FMT, of which 2 did not respond to treatment. There was no significant difference between patients with liver disease and the rest of the cohort with regard to FMT response (12/14 (87%) vs. 164/187 (88%).

CONCLUSION

FMT is a safe and effective therapy against CDI for patients with CLD and cirrhosis.

The human gut bacteria Christensenellaceae are widespread, heritable, and associated with health

The Christensenellaceae, a recently described family in the phylum Firmicutes, is emerging as an important player in human health. The relative abundance of Christensenellaceae in the human gut is inversely related to host body mass index (BMI) in different populations and multiple studies, making its relationship with BMI the most robust and reproducible link between the microbial ecology of the human gut and metabolic disease reported to date. The family is also related to a healthy status in a number of other different disease contexts, including obesity and inflammatory bowel disease. In addition, Christensenellaceae is highly heritable across multiple populations, although specific human genes underlying its heritability have so far been elusive. Further research into the microbial ecology and metabolism of these bacteria should reveal mechanistic underpinnings of their host-health associations and enable their development as therapeutics.

Biomarkers of leaky gut are related to inflammation and reduced physical function in older adults with cardiometabolic disease and mobility limitations

Intestinal barrier dysfunction is hypothesized to be a contributing determinant of two prominent characteristics of aging: inflammation and decline in physical function. A relationship between microbial translocation (MT), or their biomarkers (lipopolysaccharide binding protein-1 [LBP-1], soluble cluster of differentiation [sCD]-14), and physical function has been reported in healthy older adults, rats, and invertebrates. However, it is not known whether the existence of comorbidities, or clinical interventions intended to reduce comorbidities through weight loss or exercise, alters this connection. We measured inflammation, MT, and physical function in 288 overweight/obese older patients with cardiometabolic disease and self-reported mobility limitations who were enrolled in a weight loss and lifestyle intervention study. At baseline, inflammatory cytokines and LBP-1 were positively correlated after adjustment for age, gender, and body mass index. A higher LBP-1 was significantly associated with poorer physical functional after covariate adjustment. Further, even when IL-6 levels were included in the models, 400-m walk time (p = 0.003), short physical performance battery (p = 0.07), and IL-8 (p < 0.001) remained positively associated with LBP-1. Lifestyle interventions improved body mass and some functional measures; however, MT and inflammation were unchanged. MT is reliably related to inflammation, and to poorer physical function in older adults with comorbid conditions. Intestinal barrier function did not appear to improve as a result of intervention assignment, suggesting alternative strategies are needed to target this pro-inflammatory pathway in aging.

Establishing a donor stool bank for faecal microbiota transplantation: methods and feasibility

Faecal microbiota transplantation (FMT) is a promising treatment, but donor selection and implementation in clinical practice are difficult. Here, we describe the establishment of a donor stool bank based on the Tissue Act. Stool donors were recruited among blood donors and asked to donate five times in a month. A screening questionnaire, a medical interview and testing of blood and stool were conducted before and after donations. Donations were made at home and transported to the lab, where 50 g of stool was suspended and filtered in saline and 20-mL glycerol (final concentration of 10%) to a volume of 170 mL. The processed stool was assigned a batch number, frozen within 2 h after defecation and stored at - 80 °C for up to 1 year. All steps were documented and cross-checked before donor stool were released for clinical use. Thirteen donors were eligible at the first interview and started donations. Two donors were excluded due to a positive Helicobacter pylori test, two withdrew consent and one was lost to follow-up. One donor took a single dose of NSAIDs 2 days prior to a donation, which was discarded. There were no other excluding findings at the second interview or testing. Eight of the 13 donors were approved as stool donors. All donated five times with each donation yielding 1-6 portions. Eighty-four portions were released for clinical use. Recruiting stool donors among blood donors is safe and effective. The Tissue Act yields an appropriate regulative framework for FMT.

Recent advances in the treatment of C. difficile using biotherapeutic agents

Clostridium difficile (C. difficile) is rapidly becoming one of the most prevalent health care–associated bacterial infections in the developed world. The emergence of new, more virulent strains has led to greater morbidity and resistance to standard therapies. The bacterium is readily transmitted between people where it can asymptomatically colonize the gut environment, and clinical manifestations ranging from frequent watery diarrhea to toxic megacolon can arise depending on the age of the individual or their state of gut dysbiosis. Several inexpensive approaches are shown to be effective against virulent C. difficile in research settings such as probiotics, fecal microbiota transfer and immunotherapies. This review aims to highlight the current advantages and limitations of the aforementioned approaches with an emphasis on recent studies.

Fecal microbiota transplantation donation: the gift that keeps on giving

Fecal microbiota transplantation (FMT) is being studied and utilized for various medical conditions including Clostridium difficile colitis, inflammatory bowel diseases (IBD), obesity, myasthenia gravis, and so on. Yet, FMT donation, whether from an individual or a stool bank, can be challenging given the numerous requirements and donor costs. Furthermore, data outcomes on recipients of FMT regarding donor's health co-morbidities, age, and weight are limited but emerging. The purpose of this review is to evaluate cost, safety, and accessibility in FMT donation.

Gastrointestinal Tract Disorders in Older Age

Considering an increase in the life expectancy leading to a rise in the elderly population, it is important to recognize the changes that occur along the process of aging. Gastrointestinal (GI) changes in the elderly are common, and despite some GI disorders being more prevalent in the elderly, there is no GI disease that is limited to this age group. While some changes associated with aging GI system are physiologic, others are pathological and particularly more prevalent among those above age 65 years. This article reviews the most important GI disorders in the elderly that clinicians encounter on a daily basis. We highlight age-related changes of the oral cavity, esophagus, stomach, small and large bowels, and the clinical implications of these changes. We review epidemiology and pathophysiology of common diseases, especially as they relate to clinical manifestation in elderly. Details regarding management of specific disease are discussed in detail if they significantly differ from the management for younger groups or if they are associated with significant challenges due to side effects or polypharmacy. Cancers of GI tract are not included in the scope of this article.

The use of faecal microbiota transplant as treatment for recurrent or refractory Clostridium difficile infection and other potential indications: joint British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS) guidelines

Interest in the therapeutic potential of faecal microbiota transplant (FMT) has been increasing globally in recent years, particularly as a result of randomised studies in which it has been used as an intervention. The main focus of these studies has been the treatment of recurrent or refractory Clostridium difficile infection (CDI), but there is also an emerging evidence base regarding potential applications in non-CDI settings. The key clinical stakeholders for the provision and governance of FMT services in the UK have tended to be in two major specialty areas: gastroenterology and microbiology/infectious diseases. While the National Institute for Health and Care Excellence (NICE) guidance (2014) for use of FMT for recurrent or refractory CDI has become accepted in the UK, clear evidence-based UK guidelines for FMT have been lacking. This resulted in discussions between the British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS), and a joint BSG/HIS FMT working group was established. This guideline document is the culmination of that joint dialogue.

Bacteria in the ageing gut: did the taming of fire promote a long human lifespan?

Unique among animals as they evolved towards Homo sapiens, hominins progressively cooked their food on a routine basis. Cooked products are characterized by singular chemical compounds, derived from the pervasive Maillard reaction. This same reaction is omnipresent in normal metabolism involving carbonyls and amines, and its products accumulate with age. The gut microbiota acts as a first line of defence against the toxicity of cooked Maillard compounds, that also selectively shape the microbial flora, letting specific metabolites to reach the blood stream. Positive selection of metabolic functions allowed the body of hominins who tamed fire to use and dispose of these age-related compounds. I propose here that, as a hopeful accidental consequence, this resulted in extending human lifespan far beyond that of our great ape cousins. The limited data exploring the role of taming fire on the human genetic setup and on its microbiota is discussed in relation with ageing.

Fecal microbiota transplantation in the treatment of Clostridium difficile infection: state of the art and literature review

ABSTRACT Clostridium difficile infection is a common complication following intestinal dysbiosis caused by abusive antibiotic use. It presents medical importance due to the high rates of recurrence and morbidity. Fecal microbiota transplantation is an effective alternative for the treatment of recurrent and refractory C. difficile infection and consists of introducing the intestinal microbiota from a healthy donor into a patient with this infection. The exact physiological mechanism by which fecal microbiota transplantation alters the intestinal microbiota is not well established, but it is clear that it restores the diversity and structure of the microbiota by promoting increased resistance to colonization by C. difficile. Several routes of transplant administration are being studied and used according to the advantages presented. All forms of application had a high cure rate, and the colonoscopic route was the most used. No relevant complications and adverse events have been documented, and the cost-effectiveness over conventional treatment has proven advantageous. Despite its efficacy, it is not commonly used as initial therapy, and more studies are needed to establish this therapy as the first option in case of refractory and recurrent Clostridium difficileinfection.

Protective Effects of Bifidobacterial Strains Against Toxigenic Clostridium difficile

Probiotics might offer an attractive alternative to prevent and control Clostridium difficile (C. difficile) infection (CDI). Limited information is available on the ability of commercially used bifidobacterial strains to inhibit C. difficile. This study examined the anti-clostridial effects of Bifidobacterium longum JDM301, a widely used commercial probiotic strain in China, in vitro and in vivo. In vitro evaluation revealed a significant reduction in C. difficile counts when JDM301 was co-cultured with C. difficile, which was correlated with the significant decrease in clostridial toxin titres (TcdA and TcdB). Furthermore, the cell-free culture supernatants (CFS) of JDM301 inhibited C. difficile growth and degraded TcdA and TcdB. Notably, the results showed that acid pH promoted the degradation of TcdA by CFS from JDM301. Furthermore, comparative studies among 10 B. longum strains were performed, which showed that the inhibitory effect of CFS from JDM301 was similar with the other 8 B. longum strains and higher than strain BLY1. However, when it was neutralized, the significant different was lost. When present together, it was suggested that the acid pH induced by probiotics not only played important roles in the growth inhibition against C. difficile resulting in the reduction of toxins titres, but also directly promoted the degradation of clostridial toxin. In vivo studies proved that JDM301 partially relieved damage to tissues caused by C. difficile and also decreased the number of C. difficile and toxin levels. In summary, our results demonstrated that the commercial strain, JDM301 could be considered a probiotic able to exert anti-toxin capability and most of the CFS from Bifidobacterium were able to inhibit the growth of C. difficile, depending on acid pH. These results highlighted a potential that JDM301 could be helpful in preventing CDI and that most of the bifidobacterial strains could (at least partially) exert protective effects by reducing toxin titres through growth inhibition against toxigenic C. difficile.

Harnessing the Power of Microbiome Assessment Tools as Part of Neuroprotective Nutrition and Lifestyle Medicine Interventions

An extensive body of evidence documents the importance of the gut microbiome both in health and in a variety of human diseases. Cell and animal studies describing this relationship abound, whilst clinical studies exploring the associations between changes in gut microbiota and the corresponding metabolites with neurodegeneration in the human brain have only begun to emerge more recently. Further, the findings of such studies are often difficult to translate into simple clinical applications that result in measurable health outcomes. The purpose of this paper is to appraise the literature on a select set of faecal biomarkers from a clinician’s perspective. This practical review aims to examine key physiological processes that influence both gastrointestinal, as well as brain health, and to discuss how tools such as the characterisation of commensal bacteria, the identification of potential opportunistic, pathogenic and parasitic organisms and the quantification of gut microbiome biomarkers and metabolites can help inform clinical decisions of nutrition and lifestyle medicine practitioners.

Clostridium difficile infection in the elderly: an update on management

The burden of Clostridium difficile infection (CDI) is profound and growing. CDI now represents a common cause of health care–associated diarrhea, and is associated with significant morbidity, mortality, and health care costs. CDI disproportionally affects the elderly, possibly explained by the following risk factors: age-related impairment of the immune system, increasing antibiotic utilization, and frequent health care exposure. In the USA, recent epidemiological studies estimate that two out of every three health care–associated CDIs occur in patients 65 years or older. Additionally, the elderly are at higher risk for recurrent CDI. Existing therapeutic options include metronidazole, oral vancomycin, and fidaxomicin. Choice of agent depends on disease severity, history of recurrence, and, increasingly, the drug cost. Bezlotoxumab, a recently approved monoclonal antibody targeting C. difficile toxin B, offers an exciting advancement into immunologic therapies. Similarly, fecal microbiota transplantation is gaining popularity as an effective option mainly for recurrent CDI. The challenge of decreasing CDI burden in the elderly involves adopting preventative strategies, optimizing initial treatment, and decreasing the risk of recurrence. Expanded strategies are certainly needed to improve outcomes in this high-risk population. This review considers available data from prospective and retrospective studies as well as case reports to illustrate the merits and gaps in care related to the management of CDI in the elderly.

Outcomes of Fecal Microbiota Transplantation for Clostridium difficile Infection in Patients with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Fecal microbiota transplantation (FMT) has recently been shown to be a promising therapy for recurrent and refractory Clostridium difficile infections (CDI) despite lack of protocol standardization. Patients with inflammatory bowel disease (IBD) present a particular challenge to CDI therapy as they are reported to have worse clinical outcomes, including higher colectomy rates and increased mortality. We aimed to assess the outcomes of FMT for recurrent CDI in patients with IBD at our healthcare system.

METHODS

We constructed a retrospective cohort of all patients who underwent FMT at our healthcare system between December 2012 and May 2014. Patients with concurrent IBD were identified. We evaluated the differences in demographic and clinical characteristics, along with the outcomes to FMT between patients with IBD as compared to the general population.

RESULTS

Over the study period, 201 patients underwent FMT of which 20 patients had concurrent IBD. Patients with IBD were younger but did not differ from the general population in terms of CDI risk factors or disease severity. The response to FMT and rate of CDI relapse in the IBD group were not statistically different compared to the rest of the cohort. The overall response rate in the IBD population was 75% at 12 weeks. Of the patients who failed FMT 4 of 5 patients had active or untreated IBD.

CONCLUSION

Fecal microbiota transplantation provides a good alternative treatment option with high success rates for recurrent or refractory Clostridium difficile infection in patients with well-controlled IBD who fail standard antimicrobial therapy.

Systematic review with meta-analysis: faecal microbiota transplantation for the induction of remission for active ulcerative colitis

BACKGROUND

Faecal microbiota transplantation (FMT) is emerging as a novel therapy for ulcerative colitis (UC). Interpretation of efficacy of FMT for UC is complicated by differences among studies in blinding, FMT administration procedures, intensity of therapy and donor stool processing methods.

AIM

To determine whether FMT is effective and safe for the induction of remission in active UC.

METHODS

Medline (Ovid), Embase and the Cochrane Library were searched from inception through February 2017. Original studies reporting remission rates following FMT for active UC were included. All study designs were included in the systematic review and a meta-analysis performed including only randomised controlled trials (RCTs).

RESULTS

There were 14 cohort studies and four RCTs that used markedly different protocols. In the meta-analysis of RCTs, clinical remission was achieved in 39 of 140 (28%) patients in the donor FMT groups compared with 13 of 137 (9%) patients in the placebo groups; odds ratio 3.67 (95% CI: 1.82-7.39, P<.01). Clinical response was achieved in 69 of 140 (49%) donor FMT patients compared to 38 of 137 (28%) placebo patients; odds ratio 2.48 (95% CI: 1.18-5.21, P=.02). In cohort studies, 39 of 168 (24%; 95% CI: 11%-40%) achieved clinical remission.

CONCLUSIONS

Despite variation in processes, FMT appears to be effective for induction of remission in UC, with no major short-term safety signals. Further studies are needed to better define dose frequency and preparation methods, and to explore its feasibility, efficacy and safety as a maintenance agent.

How to: Establish and run a stool bank

BACKGROUND

Since 2013, several stool banks have been developed following publications reporting on clinical success of 'faecal microbiota transplantation' (FMT) for recurrent Clostridium difficile infections (CDI). However, protocols for donor screening, faecal suspension preparation, and transfer of the faecal suspension differ between countries and institutions. Moreover, no European consensus exists regarding the legislative aspects of the faecal suspension product. Internationally standardized recommendations about the above mentioned aspects have not yet been established.

OBJECTIVE

In 2015, the Netherlands Donor Feces Bank (NDFB) was founded with the primary aim of providing a standardized product for the treatment of patients with recurrent CDI in the Netherlands. Standard operation procedures for donor recruitment, donor selection, donor screening, and production, storage, and distribution of frozen faecal suspensions for FMT were formulated.

RESULTS AND DISCUSSION

Our experience summarized in this review addresses current donor recruitment and screening, preparation of the faecal suspension, transfer of the faecal microbiota suspension, and the experiences and follow-up of the patients treated with donor faeces from the NDFB.