Current Status and Future Therapeutic Options for Fecal Microbiota Transplantation

Decoding the role of the gut microbiome in gut-brain axis, stress-resilience, or stress-susceptibility: A review

Increased exposure to stress is associated with stress-related disorders, including depression, anxiety, and neurodegenerative conditions. However, susceptibility to stress is not seen in every individual exposed to stress, and many of them exhibit resilience. Thus, developing resilience to stress could be a big breakthrough in stress-related disorders, with the potential to replace or act as an alternative to the available therapies. In this article, we have focused on the recent advancements in gut microbiome research and the potential role of the gut-brain axis (GBA) in developing resilience or susceptibility to stress. There might be a complex interaction between the autonomic nervous system (ANS), immune system, endocrine system, microbial metabolites, and bioactive lipids like short-chain fatty acids (SCFAs), neurotransmitters, and their metabolites that regulates the communication between the gut microbiota and the brain. High fiber intake, prebiotics, probiotics, plant supplements, and fecal microbiome transplant (FMT) could be beneficial against gut dysbiosis-associated brain disorders. These could promote the growth of SCFA-producing bacteria, thereby enhancing the gut barrier and reducing the gut inflammatory response, increase the expression of the claudin-2 protein associated with the gut barrier, and maintain the blood-brain barrier integrity by promoting the expression of tight junction proteins such as claudin-5. Their neuroprotective effects might also be related to enhancing the expression of brain-derived neurotrophic factor (BDNF) and glucagon-like peptide (GLP-1). Further investigations are needed in the field of the gut microbiome for the elucidation of the mechanisms by which gut dysbiosis contributes to the pathophysiology of neuropsychiatric disorders.

Gut microbiota changes in animal models of spinal cord injury: a preclinical systematic review and meta-analysis

BACKGROUND

An increasing number of studies show that the intestinal flora is closely related to spinal cord injury. Many researchers are exploring the changes in the richness, diversity, and evenness of intestinal flora in spinal cord injury animal models to identify the characteristic bacteria.

METHODS

A comprehensive literature search was conducted using three databases: PubMed, Embase, and Web of Science. A meta-analysis was performed using R 4.3.1 to evaluate the comparison of microbiota diversity, richness, and evenness and the relative abundance of intestinal microbiota in animals with spinal cord injury and blank controls.

RESULTS

Fifteen studies were included in the meta-analysis, of which 12 involved gut microbiota distribution indicators and 11 included intestinal microflora relative abundance indicators. Meta-analysis of high-dimensional indicators describing the distribution of the gut microbiota identified a substantial decline in the evenness and richness of the intestinal flora. In addition, the Actinobacteria phylum and Erysipelotrichales and Clostridiales orders were significantly different between the spinal cord injury and sham groups; therefore, they may be the characteristic bacteria in spinal cord injury models.

CONCLUSION

Our meta-analysis suggested that the gut microbiota in the spinal cord injury animal model group was altered compared with that in the control group, with varying degrees of changes in richness and evenness and potentially pathogenic characteristic flora. More rigorous methodological studies are needed because of the high heterogeneity and limited sample size. Further research is needed to clinically apply intestinal microbiota and potentially guide fecal microbiota transplantation therapy.

Microbiota, Diet and Acute Leukaemia: Tips and Tricks on Their Possible Connections

Acute leukaemia is probably one of the most recurrent cancers in children and younger adults, with an incidence of acute lymphoblastic leukaemia in 80% of cases and an incidence of acute myeloid leukaemia in 15% of cases. Yet, while incidence is common in children and adolescents, acute leukaemia is a rare disease whose aetiology still requires further analysis. Many studies have investigated the aetiology of acute leukaemia, reporting that the formation of gut microbiota may be modified by the start and development of many diseases. Considering that in patients affected by acute lymphoblastic leukaemia, there is an inherent disequilibrium in the gut microbiota before treatment compared with healthy patients, increasing evidence shows how dysbiosis of the gut microbiota provokes an inflammatory immune response, contributing to the development of cancer. Our analysis suggeststhe key role of gut microbiota in the modulation of the efficacy of leukaemia treatment as well as in the progress of many cancers, such as acute leukaemia. Therefore, in this paper, we present an examination of information found in literature regarding the role of dietary factors and gut microbiota alterations in the development of leukaemia and suggest possible future preventive and therapeutic strategies.

Microbiota and IL-33/31 Axis Linkage: Implications and Therapeutic Perspectives in Atopic Dermatitis and Psoriasis

Microbiome dysbiosis and cytokine alternations are key features of atopic dermatitis (AD) and psoriasis (PsO), two of the most prevalent and burdensome pruritic skin conditions worldwide. Interleukin (IL)-33 and IL-31 have been recognized to be major players who act synergistically in the pathogenesis and maintenance of different chronic inflammatory conditions and pruritic skin disorders, including AD and PsO, and their potential role as therapeutic targets is being thoroughly investigated. The bidirectional interplay between dysbiosis and immunological changes has been extensively studied, but there is still debate regarding which of these two factors is the actual causative culprit behind the aetiopathological process that ultimately leads to AD and PsO. We conducted a literature review on the Pubmed database assessing articles of immunology, dermatology, microbiology and allergology with the aim to strengthen the hypothesis that dysbiosis is at the origin of the IL-33/IL-31 dysregulation that contributes to the pathogenesis of AD and PsO. Finally, we discussed the therapeutic options currently in development for the treatment of these skin conditions targeting IL-31, IL-33 and/or the microbiome.

Effectiveness of Fecal Microbiota Transplantation Treatment in Patients With Recurrent Clostridium difficile Infection, Ulcerative Colitis, and Crohn's Disease: A Systematic Review

Cronh's disease and ulcerative colitis (UC) are diseases with unknown etiologies that cause ongoing inflammation in the gastrointestinal system. Chron's disease causes immunological dysregulation, and UC causes intestinal harm due to immune reactions. According to our study, fecal microbiota transplantation (FMT) has many benefits in the treatment of inflammatory bowel disease (IBD) by restoring intestinal homeostasis and reducing clinical symptoms. In mildly symptomatic patients with UC, an FMT treatment combined with an anti-inflammatory diet can produce remission, which would then be followed by a diet that maintained the anti-inflammatory effects. The efficacy of FMT consists of preventing flares or the consequences of IBD. As a result, we must emphasize that more investigation should be done before developing a therapeutic procedure for FMT in IBD and its associated consequences.

Therapeutic Perspectives for Microbiota Transplantation in Digestive Diseases and Neoplasia-A Literature Review

In a mutually beneficial connection with its host, the gut microbiota affects the host's nutrition, immunity, and metabolism. An increasing number of studies have shown links between certain types of disease and gut dysbiosis or specific microorganisms. Fecal microbiota transplantation (FMT) is strongly advised for the treatment of recurrent or resistant Clostridium difficile infection (CDI) due to its outstanding clinical effectiveness against CDI. The therapeutic potential of FMT for other disorders, particularly inflammatory bowel diseases and malignancies, is currently gaining more and more attention. We summarized the most recent preclinical and clinical evidence to show the promise of FMT in the management of cancer as well as complications related to cancer treatment after reviewing the most recent research on the gut microbiota and its relationship to cancer.

Conjugated linoleic acid alleviates glycolipid metabolic disorders by modulating intestinal microbiota and short-chain fatty acids in obese rats

Although conjugated linoleic acid (CLA) has been shown to have anti-obesity properties, the effect and mechanism of CLA in alleviating glycolipid metabolism disorders remains unclear. In this work, it was observed that rats fed a high-fat diet (HFD) had lower body weight and body fat levels after 9 weeks of low-dose and high-dose CLA interventions. The results of blood biochemical indices showed that CLA significantly reduced the levels of total cholesterol, triglycerides, fasting blood glucose and insulin. Additionally, high-dose CLA could restore the intestinal microbiota composition, including increasing the relative abundances of short-chain fatty acid (SCFA)-producing microbiota, such as Dubosiella, Faecalibaculum and Bifidobacterium; decreasing the relative abundances of Enterococcus and Ruminococcus_2; and increasing the content of SCFAs in feces and serum. Further analysis showed that high-dose CLA could increase the expression levels of Insr, Irs-2, Akt and Glut4 in the liver tissue of HFD-induced obese rats. Consistently, high dose of CLA could reversibly improve the downregulation of INSR, AKT, PI3K and GLUT4 protein expression caused by HFD and reverse the decline in AKT phosphorylation levels. Correlation clustering analysis with a heatmap showed that the changes in specific microbiota induced by high-dose CLA were correlated with changes in obesity-related indices and gene expression. The molecular docking analysis showed that the molecular docking of SCFAs with the IRS-2, AKT and GLUT4 proteins had high linking activity. The results supported that CLA can alleviate glycolipid metabolic imbalances associated with obesity by altering the intestinal microbiota to induce the production of SCFAs and thereby activate the INSR/IRS-2/AKT/GLUT4 pathway. This study supports CLA may be preferentially used by the intestinal microbiota of the host to promote its health.

Efficacy and safety of fecal microbiota transplantation via colonoscopy as add-on therapy in patients with mild-to-moderate ulcerative colitis: A randomized clinical trial

Introduction

Growing evidence supports the effectiveness of fecal microbiota transplantation (FMT) in treating ulcerative colitis (UC), although its effects seem to depend on the method of introduction, the number of procedures, the donor material, and the severity of UC.

Aim

This study aimed to assess FMT's clinical and microbiological efficacy, tolerability, and safety in patients with mild-to-moderate UC.

Material and methods

Patients with mild-to-moderate UC were randomized into two groups. The first group (standard-care, n = 27) was treated with basic therapy-mesalazine-at a daily dose of 3 g (2 g orally + 1 g rectally). In the second group (FMT group, n = 26), while taking mesalazine at the indicated dose, each patient with UC as add-on therapy underwent a single FMT procedure with fresh material delivered by colonoscopy from a healthy donor. The clinical efficacy of treatment in both groups was evaluated after 4 and 8 weeks. The primary outcome was remission of UC, defined as a partial Mayo score ≤2, and decreased fecal calprotectin. All patients underwent bacteriological examination of feces for quantitative microbiota composition changes.

Results

Clinical response in the form of a significant decrease in stool frequency and a tendency to normalize its consistency after 4 weeks was detected in 14 (51.9%) patients of the standard care group and 16 patients (61.5%) of the FMT group (p = 0.583). The Mayo score in the standard care group was 3.59 ± 1.21 and in the FMT group-3.15±1.04 (p=0.166). After 8 weeks, the main primary endpoint was achieved in 70.4% of the standard-care group patients as compared to 84.6% of participants who received FMT as add-on therapy (p = 0.215). A more pronounced decrease in Mayo score was observed in the FMT group compared to the standard-care group (1.34 ± 1.44 vs. 2.14 ± 1.4; p = 0.045). All patients also showed a significant decrease in fecal calprotectin levels, which correlated with clinical data, stool frequency, and clinical remission. An improvement in gut microbiota composition was noted in both groups, albeit it was significantly more pronounced in the FMT group.

Conclusions

FTM in patients with mild-to-moderate UC is a well-tolerated, effective, and safe method of treatment in comparison to basic therapy.

Clinical trial registration

https://clinicaltrials.gov/ct2/show/NCT05538026?term=kobyliak&draw=2&rank=4, identifier: NCT05538026.

Advancement in Therapeutic Intervention of Prebiotic-Based Nanoparticles for Colonic Diseases

Intestinal flora has become a therapeutic target for the intervention of colonic diseases (CDs) with better understanding of the interplay between microbiota and CDs. Depending on unique properties and prominent ability of regulating the intestinal flora, prebiotics can not only achieve a colon-specific drug delivery but also maintain the intestinal homeostasis, thus playing a positive role in the intervention of CDs. Currently, different studies on prebiotic-based nanoparticles have been contrived for colonic drug delivery and have shown great potential in curing various CDs, such as colitis and colorectal cancer. Nevertheless, there is a lack of systematic survey on the use of prebiotic nanoparticles for the treatment of CDs. This review aims to generalize the state-of-the-art of prebiotic nanomedicines specific for CDs. The species and function of intestinal flora and various kinds of prebiotics available as well as their regulating effects on intestinal flora were expounded. A variety of prebiotic nanoparticles pertinent to colon-targeted drug delivery systems were illustrated with particular emphasis on their curative activities on CDs. The efficacy and safety of prebiotic-based colonic drug delivery systems (p-CDDs) were also analyzed. In conclusion, the synergy between prebiotic nanoparticles and their cargos may hold promise for the treatment and intervention of CDs.

Modulating the Gut Microbiota as a Therapeutic Intervention for Alzheimer's Disease

Growing evidence suggested that the change of composition and proportion of intestinal microbiota may be related to many diseases, such as irritable bowel syndrome, bipolar disorder, Parkinson's disease, as well as Alzheimer's disease. Current literature supports the fact that unbalanced gut microbial composition (gut dysbiosis) is a risk factor for AD. In our review, we briefly sum up the recent progress regarding the correlations between the gut microbiota and AD. Therapeutic interventions capable of modulating the make-up of the gut microflora may exert beneficial effects on AD, preventing or delaying the beginning of AD or counteracting its development. Additionally, well-documented approaches that can positively influence AD may exert their beneficial effects through modifying the gut microbiota. Therefore, other novel interventions which can target on gut microbiota will also be potential therapies for AD. The chances and challenges that AD is confronted with in the research field of microbiomics are also discussed in this review.

Gut microbiota in acute leukemia: Current evidence and future directions

Gut microbiota includes a large number of microorganisms inhabiting the human gastrointestinal tract, which show a wide range of physiological functions, including digestion, metabolism, immunity, neural development, etc., and are considered to play an increasingly important role in health and disease. A large number of studies have shown that gut microbiota are closely associated with the onset and development of several diseases. In particular, the interaction between gut microbiota and cancer has recently attracted scholars' attention. Acute leukemia (AL) is a common hematologic malignancy, especially in children. Microbiota can affect hematopoietic function, and the effects of chemotherapy and immunotherapy on AL are noteworthy. The composition and diversity of gut microbiota are important factors that influence and predict the complications and prognosis of AL after chemotherapy or hematopoietic stem cell transplantation. Probiotics, prebiotics, fecal microbiota transplantation, and dietary regulation may reduce side effects of leukemia therapy, improve response to treatment, and improve prognosis. This review concentrated on the role of the gut microbiota in the onset and development of AL, the response and side effects of chemotherapy drugs, infection during treatment, and therapeutic efficacy. According to the characteristics of gut microbes, the applications and prospects of microbial preparations were discussed.

Fecal microbiota transplantation as a promising treatment option for osteoporosis

Osteoporosis is a systemic metabolic bone disease characterized by the descending bone mass and destruction of bone microstructure, which tends to result in the increased bone fragility and associated fractures, as well as high disability rate and mortality. The relation between gut microbiota and bone metabolism has gradually become a research hotspot, and it has been verified that gut microbiota is closely associated with reduction of bone mass and incidence of osteoporosis recently. As a novel "organ transplantation" technique, fecal microbiota transplantation (FMT) mainly refers to the transplantation of gut microbiota from healthy donors to recipients with gut microbiota imbalance, so that the gut microbiota in recipients can be reshaped and play a normal function, and further prevent or treat the diseases related to gut microbiota disorder. Herein, based on the gut-bone axis and proven regulatory effects of gut microbiota on osteoporosis, this review expounds relevant basic researches and clinical practice of FMT on osteoporosis, thus demonstrating the potentials of FMT as a therapeutic option for osteoporosis and further providing certain reference for the future researches.

Fecal microbiota transplantation in patients with post-infectious irritable bowel syndrome: A randomized, clinical trial

Introduction

Research in recent years has shown the potential benefits of fecal microbiota transplantation (FMT) for irritable bowel syndrome (IBS). Acute infectious gastroenteritis is a well-established risk factor for developing such forms of IBS as post-infectious IBS (PI-IBS). However, the effective use of FMT in patients with IP-IBS has not yet been clarified.

Aim

The study aimed to conduct a single-center, randomized clinical trial (RCT) to assess FMT’s safety, clinical and microbiological efficacy in patients with PI-IBS.

Materials and methods

Patients with PI-IBS were randomized into two groups: I (standard-care, n = 29) were prescribed basic therapy, namely a low FODMAP diet, as well as Otilonium Bromide (1 tablet TID) and a multi-strain probiotic (1 capsule BID) for 1 month; II (FMT group, n = 30), each patient with PI-IBS underwent a single FMT procedure with fresh material by colonoscopy. All patients underwent bacteriological examination of feces for quantitative and qualitative microbiota composition changes. The clinical efficacy of treatment was evaluated according to the dynamics of abdominal symptoms, measured using the IBS-SSS scale, fatigue reduction (FAS scale), and a change in the quality of life (IBS-QoL scale).

Results

FMT was associated with rapid onset of the effect, manifested in a significant difference between IBS-SSS points after 2 weeks of intervention (p < 0.001). In other time points (after 4 and 12 weeks) IBS-SSS did not differ significantly across both groups. Only after 3 months of treatment did their QoL exceed its initial level, as well value for 2 and 4 weeks, to a significant extent. The change in the ratio of the main microbial phenotypes in the form of an increase in the relative abundance of Firmicutes and Bacteroidetes was recorded in all patients after 4 weeks. It should be noted that these changes were significant but eventually normalized only in the group of PI-IBS patients who underwent FMT. No serious adverse reactions were noted.

Conclusion

This comparative study of the results of FMT use in patients with PI-IBS demonstrated its effectiveness compared to traditional pharmacotherapy, as well as a high degree of safety and good tolerability.

Gut Microbiota and Therapy in Metastatic Melanoma: Focus on MAPK Pathway Inhibition

Gut microbiome (GM) and its either pro-tumorigenic or anti-tumorigenic role is intriguing and constitutes an evolving landscape in translational oncology. It has been suggested that these microorganisms may be involved in carcinogenesis, cancer treatment response and resistance, as well as predisposition to adverse effects. In melanoma patients, one of the most immunogenic cancers, immune checkpoint inhibitors (ICI) and MAPK-targeted therapy—BRAF/MEK inhibitors—have revolutionized prognosis, and the study of the microbiome as a modulating factor is thus appealing. Although BRAF/MEK inhibitors constitute one of the main backbones of treatment in melanoma, little is known about their impact on GM and how this might correlate with immune re-induction. On the contrary, ICI and their relationship to GM has become an interesting field of research due to the already-known impact of immunotherapy in modulating the immune system. Immune reprogramming in the tumor microenvironment has been established as one of the main targets of microbiome, since it can induce immunosuppressive phenotypes, promote inflammatory responses or conduct anti-tumor responses. As a result, ongoing clinical trials are evaluating the role of fecal microbiota transplant (FMT), as well as the impact of using dietary supplements, antibiotics and probiotics in the prediction of response to therapy. In this review, we provide an overview of GM’s link to cancer, its relationship with the immune system and how this may impact response to treatments in melanoma patients. We also discuss insights about novel therapeutic approaches including FMT, changes in diet and use of probiotics, prebiotics and symbiotics. Finally, we hypothesize on the possible pathways through which GM may impact anti-tumor efficacy in melanoma patients treated with targeted therapy, an appealing subject of which little is known.

Evaluation of serum calprotectin as novel biomarker in psoriatic patients: a prospective pilot study

BACKGROUND

Psoriasis is a chronic immune-mediated inflammatory disease characterized by erythematous plaques that can extend along the entire skin surface. In the latest years, it has been shown that serum calprotectin correlated strongly with several inflammatory biomarkers. Since high levels of calprotectin have been found in psoriatic lesions, it is of paramount importance to investigate the role of serum calprotectin as a possible novel diagnostic marker of psoriasis. Aim of our prospective pilot study was to assess the level of serum calprotectin in psoriatic patients.

METHODS

Between January 2018 and July 2019, 45 subjects were enrolled at the Dermatology Unit of Magna Graecia University of Catanzaro, Italy. Thirty-two of them were psoriatic patients and 13 healthy controls. Psoriasis severity was assessed by the Psoriasis Area Severity Index.

RESULTS

A statistically significant difference between the two groups (P=0.01) was found in terms of body mass index, higher among patients than in controls. By performing the Student's t-test for unpaired data, serum calprotectin resulted significantly higher (P=0.033) among psoriatic patients than in controls. Furthermore, performing the receiver operator characteristic curve analysis, serum calprotectin showed a significant area under the curve, implying its possible role in finding psoriatic patients. Our study aimed to evaluate the serum levels of calprotectin in a group of psoriatic patients and in a control group. The results showed that serum calprotectin levels were significantly higher in the patient group than in the control group. This result confirms the observations present in the literature.

CONCLUSIONS

In this pilot study psoriatic patients had a significant high level of serum calprotectin than healthy subjects, and this biomarker had high accuracy in identifying patients. Further studies, with larger sample size will need to confirm our data.

Reshaping the Gut Microbiota Through Lifestyle Interventions in Women with PCOS: A Review

Polycystic ovary syndrome (PCOS) is an endocrine disorder evolving as a global threat to women's health. However, its multifactorial etiology causes difficulty in eliminating it. The interrelation between the gut microbiota and metabolic disorders has been trending recently, giving rise to new opportunities on the etiology and pathogenesis of PCOS. Lifestyle interventions such as healthy diet, physical exercises, and behavioral interventions such as regulation of stress and sleep cycles have been identified to improve the symptoms of PCOS across the endocrinological, metabolic and psychological scales and are recommended as the first line of treatment for PCOS. The impact of the unhealthy lifestyle factors on intestinal dysbiosis that cause PCOS is summarized in this review. This review also provides an insight on the therapeutic approaches that primarily target the gut microbiota and offers novel gut microflora-associated treatment strategies for PCOS. Further, this survey also highlights the need for the implementation of lifestyle management strategies and strongly recommends a healthy and stress-free lifestyle to promote gut health and manage PCOS.

Mechanisms of mucosal healing: treating inflammatory bowel disease without immunosuppression?

Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.

Mechanisms of mucosal healing: treating inflammatory bowel disease without immunosuppression?

Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.