Microbiota Transfer Therapy alters gut ecosystem and improves gastrointestinal and autism symptoms: an open-label study

Gut flora in multiple sclerosis: implications for pathogenesis and treatment

ABSTRACT

Multiple sclerosis is an inflammatory disorder characterized by inflammation, demyelination, and neurodegeneration in the central nervous system. Although current first-line therapies can help manage symptoms and slow down disease progression, there is no cure for multiple sclerosis. The gut-brain axis refers to complex communications between the gut flora and the immune, nervous, and endocrine systems, which bridges the functions of the gut and the brain. Disruptions in the gut flora, termed dysbiosis, can lead to systemic inflammation, leaky gut syndrome, and increased susceptibility to infections. The pathogenesis of multiple sclerosis involves a combination of genetic and environmental factors, and gut flora may play a pivotal role in regulating immune responses related to multiple sclerosis. To develop more effective therapies for multiple sclerosis, we should further uncover the disease processes involved in multiple sclerosis and gain a better understanding of the gut-brain axis. This review provides an overview of the role of the gut flora in multiple sclerosis.

Relative dispersion ratios following fecal microbiota transplant elucidate principles governing microbial migration dynamics

Microorganisms frequently migrate from one ecosystem to another. Yet, despite the potential importance of this process in modulating the environment and the microbial ecosystem, our understanding of the fundamental forces that govern microbial dispersion is still lacking. Moreover, while theoretical models and in-vitro experiments have highlighted the contribution of species interactions to community assembly, identifying such interactions in vivo, specifically in communities as complex as the human gut, remains challenging. To address this gap, here we introduce a robust and rigorous computational framework, termed Relative Dispersion Ratio (RDR) analysis, and leverage data from well-characterized fecal microbiota transplant trials, to rigorously pinpoint dependencies between taxa during the colonization of human gastrointestinal tract. Our analysis identifies numerous pairwise dependencies between co-colonizing microbes during migration between gastrointestinal environments. We further demonstrate that identified dependencies agree with previously reported findings from in-vitro experiments and population-wide distribution patterns. Finally, we explore metabolic dependencies between these taxa and characterize the functional properties that facilitate effective dispersion. Collectively, our findings provide insights into the principles and determinants of community dynamics following ecological translocation, informing potential opportunities for precise community design.

Human-derived fecal microbiota transplantation alleviates social deficits of the BTBR mouse model of autism through a potential mechanism involving vitamin B6 metabolism

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental condition characterized by social communication deficiencies and stereotypic behaviors influenced by hereditary and/or environmental risk factors. There are currently no approved medications for treating the core symptoms of ASD. Human fecal microbiota transplantation (FMT) has emerged as a potential intervention to improve autistic symptoms, but the underlying mechanisms are not fully understood. In this study, we evaluated the effects of human-derived FMT on behavioral and multi-omics profiles of the BTBR mice, an established model for ASD. FMT effectively alleviated the social deficits in the BTBR mice and normalized their distinct plasma metabolic profile, notably reducing the elevated long-chain acylcarnitines. Integrative analysis linked these phenotypic changes to specific Bacteroides species and vitamin B6 metabolism. Indeed, vitamin B6 supplementation improved the social behaviors in BTBR mice. Collectively, these findings shed new light on the interplay between FMT and vitamin B6 metabolism and revealed a potential mechanism underlying the therapeutic role of FMT in ASD.IMPORTANCEAccumulating evidence supports the beneficial effects of human fecal microbiota transplantation (FMT) on symptoms associated with autism spectrum disorder (ASD). However, the precise mechanism by which FMT induces a shift in the microbiota and leads to symptom improvement remains incompletely understood. This study integrated data from colon-content metagenomics, colon-content metabolomics, and plasma metabolomics to investigate the effects of FMT treatment on the BTBR mouse model for ASD. The analysis linked the amelioration of social deficits following FMT treatment to the restoration of mitochondrial function and the modulation of vitamin B6 metabolism. Bacterial species and compounds with beneficial roles in vitamin B6 metabolism and mitochondrial function may further contribute to improving FMT products and designing novel therapies for ASD treatment.

Neuromodulation and the Gut-Brain Axis: Therapeutic Mechanisms and Implications for Gastrointestinal and Neurological Disorders

The gut-brain axis (GBA) represents a complex, bidirectional communication network that intricately connects the gastrointestinal tract with the central nervous system (CNS). Understanding and intervening in this axis opens a pathway for therapeutic advancements for neurological and gastrointestinal diseases where the GBA has been proposed to play a role in the pathophysiology. In light of this, the current review assesses the effectiveness of neuromodulation techniques in treating neurological and gastrointestinal disorders by modulating the GBA, involving key elements such as gut microbiota, neurotrophic factors, and proinflammatory cytokines. Through a comprehensive literature review encompassing PubMed, Google Scholar, Web of Science, and the Cochrane Library, this research highlights the role played by the GBA in neurological and gastrointestinal diseases, in addition to the impact of neuromodulation on the management of these conditions which include both gastrointestinal (irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and gastroesophageal reflux disease (GERD)) and neurological disorders (Parkinson's disease (PD), Alzheimer's disease (AD), autism spectrum disorder (ASD), and neuropsychiatric disorders). Despite existing challenges, the ability of neuromodulation to adjust disrupted neural pathways, alleviate pain, and mitigate inflammation is significant in improving the quality of life for patients, thereby offering exciting prospects for future advancements in patient care.

Precision synbiotics increase gut microbiome diversity and improve gastrointestinal symptoms in a pilot open-label study for autism spectrum disorder

The efficacy of prebiotics and probiotics (synbiotics when combined) to improve symptoms associated with autism spectrum disorder (ASD) has shown considerable inter-study variation, likely due to the complex, heterogeneous nature of the disorder and its associated behavioral, developmental, and gastrointestinal symptoms. Here, we present a precision synbiotic supplementation study in 296 children and adults diagnosed with ASD versus 123 age-matched neurotypical controls. One hundred seventy ASD participants completed the study. Baseline and post-synbiotic assessment of ASD and gastrointestinal (GI) symptoms and deep metagenomic sequencing were performed. Within the ASD cohort, there were significant differences in microbes between subpopulations based on the social responsiveness scale (SRS2) survey (Prevotella spp., Bacteroides, Fusicatenibacter, and others) and gluten and dairy-free diets (Bifidobacterium spp., Lactococcus, Streptococcus spp., and others). At the baseline, the ASD cohort maintained a lower taxonomic alpha diversity and significant differences in taxonomic composition, metabolic pathways, and gene families, with a greater proportion of potential pathogens, including Shigella, Klebsiella, and Clostridium, and lower proportions of beneficial microbes, including Faecalibacterium compared to controls. Following the 3-month synbiotic supplementation, the ASD cohort showed increased taxonomic alpha diversity, shifts in taxonomy and metabolic pathway potential, and improvements in some ASD-related symptoms, including a significant reduction in GI discomfort and overall improved language, comprehension, cognition, thinking, and speech. However, the open-label study design may include some placebo effects. In summary, we found that precision synbiotics modulated the gut microbiome and could be used as supplementation to improve gastrointestinal and ASD-related symptoms.

IMPORTANCE

Autism spectrum disorder (ASD) is prevalent in 1 out of 36 children in the United States and contributes to health, financial, and psychological burdens. Attempts to identify a gut microbiome signature of ASD have produced varied results. The limited pre-clinical and clinical population sizes have hampered the success of these trials. To understand the microbiome associated with ASD, we employed whole metagenomic shotgun sequencing to classify microbial composition and genetic functional potential. Despite being one of the most extensive ASD post-synbiotic assessment studies, the results highlight the complexity of performing such a case-control supplementation study in this population and the potential for a future therapeutic approach in ASD.

Effects and microbiota changes following oral lyophilized fecal microbiota transplantation in children with autism spectrum disorder

Background and purpose

Autism spectrum disorder (ASD) is a group of heterogeneous neurodevelopmental disorders that is characterized by core features in social communication impairment and restricted, repetitive sensory-motor behaviors. This study aimed to further investigate the utilization of fecal microbiota transplantation (FMT) in children with ASD, both with and without gastrointestinal (GI) symptoms, evaluate the effect of FMT and analyze the alterations in bacterial and fungal composition within the gut microbiota.

Methods

A total of 38 children diagnosed with ASD participated in the study and underwent oral lyophilized FMT treatment. The dosage of the FMT treatment was determined based on a ratio of 1 g of donor stool per 1 kg of recipient body weight, with a frequency of once every 4 weeks for a total of 12 weeks. In addition, 30 healthy controls (HC) were included in the analysis. The clinical efficacy of FMT was evaluated, while the composition of fecal bacteria and fungi was determined using 16S rRNA and ITS gene sequencing methods.

Results

Median age of the 38 children with ASD was 7 years. Among these children, 84.2% (32 of 38) were boys and 81.6% (31 of 38) exhibited GI symptoms, with indigestion, constipation and diarrhea being the most common symptoms. Sample collections and assessments were conducted at baseline (week 0), post-treatment (week 12) and follow-up (week 20). At the end of the follow-up phase after FMT treatment, the autism behavior checklist (ABC) scores decreased by 23% from baseline, and there was a 10% reduction in scores on the childhood autism rating scale (CARS), a 6% reduction in scores on the social responsiveness scale (SRS) and a 10% reduction in scores on the sleep disturbance scale for children (SDSC). In addition, short-term adverse events observed included vomiting and fever in 2 participants, which were self-limiting and resolved within 24 h, and no long-term adverse events were observed. Although there was no significant difference in alpha and beta diversity in children with ASD before and after FMT therapy, the FMT treatment resulted in alterations in the relative abundances of various bacterial and fungal genera in the samples of ASD patients. Comparisons between children with ASD and healthy controls (HC) revealed statistically significant differences in microbial abundance before and after FMT. Blautia, Sellimonas, Saccharomycopsis and Cystobasidium were more abundant in children with ASD than in HC, while Dorea were less abundant. After FMT treatment, levels of Blautia, Sellimonas, Saccharomycopsis and Cystobasidium decreased, while levels of Dorea increased. Moreover, the increased abundances of Fusicatenibacter, Erysipelotrichaceae_UCG-003, Saccharomyces, Rhodotorula, Cutaneotrichosporon and Zygosaccharomyces were negatively correlated with the scores of ASD core symptoms.

Conclusions

Oral lyophilized FMT could improve GI and ASD related symptoms, as well as sleep disturbances, and alter the gut bacterial and fungal microbiota composition in children with ASD.

Clinical Trial Registration

Chinese Clinical Trial Registry, ChiCTR2200055943. Registered 28 January 2022, www.chictr.org.cn.

Microglial Dysfunction in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a highly heterogeneous neurodevelopmental disorder with onset in childhood. The molecular mechanisms underlying ASD have not yet been elucidated completely. Evidence has emerged to support a link between microglial dysfunction and the etiology of ASD. This review summarizes current research on microglial dysfunction in neuroinflammation and synaptic pruning, which are associated with altered transcriptomes and autophagy in ASD. Dysbiosis of gut microbiota in ASD and its correlation with microglial dysfunction are also addressed.

The Potential Impact of the Gut Microbiota on Neonatal Brain Development and Adverse Health Outcomes

Over the past decade, microbiome research has significantly expanded in both scope and volume, leading to the development of new models and treatments targeting the gut-brain axis to mitigate the effects of various disorders. Related research suggests that interventions during the critical period from birth to three years old may yield the greatest benefits. Investigating the substantial link between the gut and brain during this crucial developmental phase raises fundamental issues about the role of microorganisms in human health and brain development. This underscores the importance of focusing on the prevention rather than the treatment of neurodevelopmental and neuropsychiatric disorders. The present review examines the gut microbiota from birth to age 3, with a particular focus on its potential relationship with neurodevelopment. This review emphasizes the immunological mechanisms underlying this relationship. Additionally, the study investigates the impact of the microbiome on cognitive development and neurobehavioral issues such as anxiety and autism. Importantly, it highlights the need to integrate mechanistic studies of animal models with epidemiological research across diverse cultures to better understand the role of a healthy microbiome in early life and the implications of dysbiosis. Furthermore, this review summarizes factors contributing to the transmission of gut microbiome-targeted therapies and their effects on neurodevelopment. Recent studies on environmental toxins known to impact neurodevelopment are also reviewed, exploring whether the microbiota may mitigate or modulate these effects.

Successful Treatment of Recurrent Clostridioides difficile Infection Using a Novel, Drinkable, Oral Formulation of Fecal Microbiota

BACKGROUND

Fecal microbiota transplants can be administered orally in encapsulated form or require invasive procedures to administer liquid formulations. There is a need for an oral liquid formulation of fecal microbiota for patients who are unable to swallow capsules, especially if they require multiple, repeated administrations.

AIMS

These studies were conducted to develop a protocol to manufacture an organoleptically acceptable powdered fecal microbiota formulation that can be suspended in a liquid carrier and used for fecal microbiota transplantation.

METHODS

Several processing steps were investigated, including extra washes of microbiota prior to lyophilization and an addition of a flavoring agent. The viability of bacteria in the transplant formulation was tested using live/dead microscopy staining and engraftment into antibiotic-treated mice. After development of a clinical protocol for suspension of the powdered microbiota, the new formulation was tested in three elderly patients with recurrent Clostridioides difficile infections and who have difficulties in swallowing capsules. Changes in the microbial community structure in one of the patients were characterized using 16S rRNA gene profiling and engraftment analysis.

RESULTS

The processing steps used to produce an organoleptically acceptable suspension of powdered fecal microbiota did not result in loss of its viability. The powder could be easily suspended in a liquid carrier. The use of the new formulation was associated with abrogation of the cycle of C. difficile infection recurrences in the three patients.

CONCLUSION

We developed a novel organoleptically acceptable liquid formulation of fecal microbiota that is suitable for use in clinical trials for patients with difficulties in swallowing capsules.

Nutraceuticals in Psychiatric Disorders: A Systematic Review

Correct nutrition and diet are directly correlated with mental health, functions of the immune system, and gut microbiota composition. Diets with a high content of some nutrients, such as fibers, phytochemicals, and short-chain fatty acids (omega-3 fatty acids), seem to have an anti-inflammatory and protective action on the nervous system. Among nutraceuticals, supplementation of probiotics and omega-3 fatty acids plays a role in improving symptoms of several mental disorders. In this review, we collect data on the efficacy of nutraceuticals in patients with schizophrenia, autism spectrum disorders, major depression, bipolar disorder, and personality disorders. This narrative review aims to provide an overview of recent evidence obtained on this topic, pointing out the direction for future research.

Food, nutrition, and autism: from soil to fork

Food and nutrition-related factors have the potential to impact development of autism spectrum disorder (ASD) and quality of life for people with ASD, but gaps in evidence exist. On 10 November 2022, Tufts University's Friedman School of Nutrition Science and Policy and Food and Nutrition Innovation Institute hosted a 1-d meeting to explore the evidence and evidence gaps regarding the relationships of food and nutrition with ASD. This meeting report summarizes the presentations and deliberations from the meeting. Topics addressed included prenatal and child dietary intake, the microbiome, obesity, food-related environmental exposures, mechanisms and biological processes linking these factors and ASD, food-related social factors, and data sources for future research. Presentations highlighted evidence for protective associations with prenatal folic acid supplementation and ASD development, increases in risk of ASD with maternal gestational obesity, and the potential for exposure to environmental contaminants in foods and food packaging to influence ASD development. The importance of the maternal and child microbiome in ASD development or ASD-related behaviors in the child was reviewed, as was the role of discrimination in leading to disparities in environmental exposures and psychosocial factors that may influence ASD. The role of child diet and high prevalence of food selectivity in children with ASD and its association with adverse outcomes were also discussed. Priority evidence gaps identified by participants include further clarifying ASD development, including biomarkers and key mechanisms; interactions among psychosocial, social, and biological determinants; interventions addressing diet, supplementation, and the microbiome to prevent and improve quality of life for people with ASD; and mechanisms of action of diet-related factors associated with ASD. Participants developed research proposals to address the priority evidence gaps. The workshop findings serve as a foundation for future prioritization of scientific research to address evidence gaps related to food, nutrition, and ASD.

Induction of autism-related behavior in male mice by early-life vitamin D deficiency: association with disruption of the gut microbial composition and homeostasis

Vitamin D deficiency (VDD) during early life emerges as a potential risk factor for autism spectrum disorder (ASD). Individuals with autism commonly exhibit lower vitamin D (VD) levels compared to the general population, and VD deficiency is prevalent during pregnancy and lactation. Moreover, gastrointestinal comorbidity, prevalent in ASD patients, correlates closely with disruptions in the gut microbiota and altered intestinal permeability. Therefore, it is fascinating and significant to explore the effects of maternal VD deficiency during pregnancy and lactation on the maturation of the gut microbiota of the offspring and its relevance to autism spectrum disorders. In this study, we established maternal pregnancy and lactation VD-deficient mouse models, employed shotgun macrogenomic sequencing to unveil alterations in the gut microbiome of offspring mice, and observed autism-related behaviours. Furthermore, fecal microbial transplantation (FMT) reversed repetitive and anxious behaviours and alleviated social deficits in offspring mice by modulating the gut microbiota and increasing short-chain fatty acid levels in the cecum, along with influencing the concentrations of claudin-1 and occludin in the colon. Our findings confirm that VDD during pregnancy and lactation is a risk factor for autism in the offspring, with disturbances in the structure and function of the offspring's gut microbiota contributing at least part of the effect. The study emphasises the importance of nutrition and gut health early in life. Simultaneously, this study further demonstrates the effect of VDD on ASD and provides potential ideas for early prevention and intervention of ASD.

The Role of the Gut Microbiome in Health and Disease in the Elderly

PURPOSE OF REVIEW

Growing evidence supports the contribution of age in the composition and function of the gut microbiome, with specific findings associated with health in old age and longevity.

RECENT FINDINGS

Current studies have associated certain microbiota, such as Butyricimonas, Akkermansia, and Odoribacter, with healthy aging and the ability to survive into extreme old age. Furthermore, emerging clinical and pre-clinical research have shown promising mechanisms for restoring a healthy microbiome in elderly populations through various interventions such as fecal microbiota transplant (FMT), dietary interventions, and exercise programs. Despite several conceptually exciting interventional studies, the field of microbiome research in the elderly remains limited. Specifically, large longitudinal studies are needed to better understand causative relationships between the microbiome and healthy aging. Additionally, individualized approaches to microbiome interventions based on patients' co-morbidities and the underlying functional capacity of their microbiomes are needed to achieve optimal results.

Periodontitis increases the risk of gastrointestinal dysfunction: an update on the plausible pathogenic molecular mechanisms

Periodontitis is an immuno-inflammatory disease of the soft tissues surrounding the teeth. Periodontitis is linked to many communicable and non-communicable diseases such as diabetes, cardiovascular disease, rheumatoid arthritis, and cancers. The oral-systemic link between periodontal disease and systemic diseases is attributed to the spread of inflammation, microbial products and microbes to distant organ systems. Oral bacteria reach the gut via swallowed saliva, whereby they induce gut dysbiosis and gastrointestinal dysfunctions. Some periodontal pathogens like Porphyromonas. gingivalis, Klebsiella, Helicobacter. Pylori, Streptococcus, Veillonella, Parvimonas micra, Fusobacterium nucleatum, Peptostreptococcus, Haemophilus, Aggregatibacter actinomycetomcommitans and Streptococcus mutans can withstand the unfavorable acidic, survive in the gut and result in gut dysbiosis. Gut dysbiosis increases gut inflammation, and induce dysplastic changes that lead to gut dysfunction. Various studies have linked oral bacteria, and oral-gut axis to various GIT disorders like inflammatory bowel disease, liver diseases, hepatocellular and pancreatic ductal carcinoma, ulcerative colitis, and Crohn's disease. Although the correlation between periodontitis and GIT disorders is well established, the intricate molecular mechanisms by which oral microflora induce these changes have not been discussed extensively. This review comprehensively discusses the intricate and unique molecular and immunological mechanisms by which periodontal pathogens can induce gut dysbiosis and dysfunction.

Infant microbes and metabolites point to childhood neurodevelopmental disorders

This study has followed a birth cohort for over 20 years to find factors associated with neurodevelopmental disorder (ND) diagnosis. Detailed, early-life longitudinal questionnaires captured infection and antibiotic events, stress, prenatal factors, family history, and more. Biomarkers including cord serum metabolome and lipidome, human leukocyte antigen (HLA) genotype, infant microbiota, and stool metabolome were assessed. Among the 16,440 Swedish children followed across time, 1,197 developed an ND. Significant associations emerged for future ND diagnosis in general and for specific ND subtypes, spanning intellectual disability, speech disorder, attention-deficit/hyperactivity disorder, and autism. This investigation revealed microbiome connections to future diagnosis as well as early emerging mood and gastrointestinal problems. The findings suggest links to immunodysregulation and metabolism, compounded by stress, early-life infection, and antibiotics. The convergence of infant biomarkers and risk factors in this prospective, longitudinal study on a large-scale population establishes a foundation for early-life prediction and intervention in neurodevelopment.

Assessing Engraftment Following Fecal Microbiota Transplant

Fecal Microbiota Transplant (FMT) is an FDA approved treatment for recurrent Clostridium difficile infections, and is being explored for other clinical applications, from alleviating digestive and neurological disorders, to priming the microbiome for cancer treatment, and restoring microbiomes impacted by cancer treatment. Quantifying the extent of engraftment following an FMT is important in determining if a recipient didn't respond because the engrafted microbiome didn't produce the desired outcomes (a successful FMT, but negative treatment outcome), or the microbiome didn't engraft (an unsuccessful FMT and negative treatment outcome). The lack of a consistent methodology for quantifying FMT engraftment extent hinders the assessment of FMT success and its relation to clinical outcomes, and presents challenges for comparing FMT results and protocols across studies. Here we review 46 studies of FMT in humans and model organisms and group their approaches for assessing the extent to which an FMT engrafts into three criteria: 1) Chimeric Asymmetric Community Coalescence investigates microbiome shifts following FMT engraftment using methods such as alpha diversity comparisons, beta diversity comparisons, and microbiome source tracking. 2) Donated Microbiome Indicator Features tracks donated microbiome features (e.g., amplicon sequence variants or species of interest) as a signal of engraftment with methods such as differential abundance testing based on the current sample collection, or tracking changes in feature abundances that have been previously identified (e.g., from FMT or disease-relevant literature). 3) Temporal Stability examines how resistant post-FMT recipient's microbiomes are to reverting back to their baseline microbiome. Individually, these criteria each highlight a critical aspect of microbiome engraftment; investigated together, however, they provide a clearer assessment of microbiome engraftment. We discuss the pros and cons of each of these criteria, providing illustrative examples of their application. We also introduce key terminology and recommendations on how FMT studies can be analyzed for rigorous engraftment extent assessment.

Prebiotic diet normalizes aberrant immune and behavioral phenotypes in a mouse model of autism spectrum disorder

Autism spectrum disorder (ASD) is a cluster of neurodevelopmental disorders characterized by deficits in communication and behavior. Increasing evidence suggests that the microbiota-gut-brain axis and the likely related immune imbalance may play a role in the development of this disorder. Gastrointestinal deficits and gut microbiota dysfunction have been linked to the development or severity of autistic behavior. Therefore, treatments that focus on specific diets may improve gastrointestinal function and aberrant behavior in individuals with ASD. In this study, we investigated whether a diet containing specific prebiotic fibers, namely, 3% galacto-oligosaccharide/fructo-oligosaccharide (GOS/FOS; 9:1), can mitigate the adverse effects of in utero exposure to valproic acid (VPA) in mice. Pregnant BALB/cByJ dams were injected with VPA (600 mg/kg, sc.) or phosphate-buffered saline (PBS) on gestational day 11 (G11). Male offspring were divided into four groups: (1) in utero PBS-exposed with a control diet, (2) in utero PBS-exposed with GOS/FOS diet, (3) in utero VPA-exposed with a control diet, and (4) in utero VPA-exposed with GOS/FOS diet. Dietary intervention started from birth and continued throughout the duration of the experiment. We showed that the prebiotic diet normalized VPA-induced alterations in male offspring, including restoration of key microbial taxa, intestinal permeability, peripheral immune homeostasis, reduction of neuroinflammation in the cerebellum, and impairments in social behavior and cognition in mice. Overall, our research provides valuable insights into the gut-brain axis involvement in ASD development. In addition, dietary interventions might correct the disbalance in gut microbiota and immune responses and, ultimately, might improve detrimental behavioral outcomes in ASD.

Advances in molecular mechanisms and therapeutic strategies for central nervous system diseases based on gut microbiota imbalance

BACKGROUD

Central nervous system (CNS) diseases pose a serious threat to human health, but the regulatory mechanisms and therapeutic strategies of CNS diseases need to be further explored. It has been demonstrated that the gut microbiota (GM) is closely related to CNS disease. GM structure disorders, abnormal microbial metabolites, intestinal barrier destruction and elevated inflammation exist in patients with CNS diseases and promote the development of CNS diseases. More importantly, GM remodeling alleviates CNS pathology to some extent.

AIM OF REVIEW

Here, we have summarized the regulatory mechanism of the GM in CNS diseases and the potential treatment strategies for CNS repair based on GM regulation, aiming to provide safer and more effective strategies for CNS repair from the perspective of GM regulation.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The abundance and composition of GM is closely associated with the CNS diseases. On the basis of in-depth analysis of GM changes in mice with CNS disease, as well as the changes in its metabolites, therapeutic strategies, such as probiotics, prebiotics, and FMT, may be used to regulate GM balance and affect its microbial metabolites, thereby promoting the recovery of CNS diseases.

The gut microbiome and sociability

The human gut microbiome plays an important role in the maturation of the neural, immune, and endocrine systems. Research data from animal models shows that gut microbiota communicate with the host's brain in an elaborate network of signaling pathways, including the vagus nerve. Part of the microbiome's influence extends to the behavioral and social development of its host. As a social species, a human's ability to communicate with others is imperative to their survival and quality of life. Current research explores the gut microbiota's developmental influence as well as how these gut-brain pathways can be leveraged to alleviate the social symptoms associated with various neurodevelopmental and psychiatric diseases. One intriguing vein of research in animal models centers on probiotic treatment, which leads to downstream increased circulation of endogenous oxytocin, a neuropeptide hormone relevant to sociability. Further research may lead to therapeutic applications in humans, particularly in the early stages of their lives.

A comparative study on dietary diversity and gut microbial diversity in children with autism spectrum disorder, attention-deficit hyperactivity disorder, their neurotypical siblings, and non-related neurotypical volunteers: a cross-sectional study

BACKGROUND

Previous research has shown a significant link between gut microbiota in children with autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). However, much remains unknown because of the heterogeneity of disorders and the potential confounders such as dietary patterns and control group variations.

METHODS

Children aged 6-12 years who had been clinically diagnosed with ASD and/or ADHD, their unaffected neurotypical siblings, and non-related neurotypical volunteers were recruited cross-sectionally. The ASD diagnosis was confirmed using the Autism Diagnostic Observation Schedule-2 (ADOS-2) in all patients, including those with ADHD. Standardized DNA extraction and sequencing methods were used to compare gut microbial alpha-diversity among the groups. Dietary diversity was calculated from a standardized dietary questionnaire form. We compared the difference in gut microbiome between patients with ASD and/or ADHD with neurotypical siblings and non-related neurotypical controls.

RESULTS

Ninety-eight subjects were included in the study (18 with ASD, 19 with ADHD, 20 with both ASD and ADHD, 13 neurotypical siblings, and 28 non-related neurotypical controls). The alpha-diversity indices, such as Chao 1 and Shannon index, showed a significant difference between the groups in a Linear mixed-effect model (F(4, 93) = 4.539, p = .02), (F(4, 93) = 3.185, p = .017), respectively. In a post-hoc pairwise comparison, patients with ASD had lower alpha-diversity compared with non-related controls after Bonferroni correction. Dietary diversity shown in Shannon index did not differ among the groups (F(4, 84) = 1.494, p = .211).

CONCLUSIONS

Our study indicates disorder-specific microbiome differences in patients with ASD. In future research on gut microbiota in neurodevelopmental disorders, it is necessary to consider the impact of ASD and ADHD co-occurrence, and strictly control for background information such as diet, to elucidate the gut-microbiota interaction in ASD and ADHD for exploring the potential of therapeutic interventions.

Just a gut feeling: Faecal microbiota transplant for treatment of depression - A mini-review

BACKGROUND

The microbiota-gut-brain axis (MGBA) allows bidirectional crosstalk between the brain and gut microbiota (GM) and is believed to contribute to regulating mood/cognition/behaviour/metabolism/health and homeostasis. Manipulation of GM through faecal microbiota transplant (FMT) is a new, exciting and promising treatment for major depressive disorder (MDD).

AIMS

This mini-review examines current research into GM and FMT as a therapy for depression.

METHODS

Original research articles published in Medline/Cochrane Library/PubMed/EMBASE/PsycINFO databases/National Institute of Health website Clinicaltrials.gov/controlled-trials.com were searched. Full articles included in reference lists were evaluated. We summarise current data on GM and depression and discuss communication through the MGBA and the interaction of antidepressants and GM through this. We review compositions of dysbiosis in depressed cohorts, focusing on future directions in the treatment of MDD.

RESULTS

Studies have demonstrated significant gut dysbiosis in depressed patients compared to healthy cohorts, with overgrowth of pro-inflammatory microbiota, reduction in anti-inflammatory species and reduced overall stability and taxonomic richness. FMT allows the introduction of healthy microbiota into the gastrointestinal tract, facilitating the restoration of eubiosis.

CONCLUSION

The GM plays an integral role in human health and disease through its communication with the rest of the body via the MGBA. FMT may provide a means to transfer the healthy phenotype into the recipient and this concept in humans is attracting enormous attention as a prospective treatment for psychopathologies, such as MDD, in the future. It may be possible to manipulate the GM in a number of ways, but further research is needed to determine the exact likelihood and profiles involved in the development and amelioration of MDD in humans, as well as the long-term effects and potential risks of this procedure.

Gut microbiota: A potential player in psychiatric symptoms during COVID-19

OBJECTIVES

This study aims to explore the potential interconnections among gut microbiota, COVID-19 infection, depression and anxiety disorder. Additionally, it tries to assess potential therapeutic interventions that may improve the dysbiosis of gut microbiota.

METHODS

To achieve these objectives, we reviewed existing literature, encompassing studies and critical reviews that intersect the domains of gut microbiota, COVID-19, depression and anxiety disorders.

RESULTS

The findings highlight a notable correlation between the dysbiosis of gut microbiota and psychiatric symptoms in the context of COVID-19. Specifically, there is a marked reduction in the populations of bacteria that generate anti-inflammatory short-chain fatty acids (SCFAs), alongside a rise in the prevalence of gut bacterial clusters linked to inflammatory processes. Furthermore, several potential treatment strategies were summarised for improving the dysbiosis.

CONCLUSIONS

Gut microbiota plays a significant role in psychiatric symptoms during COVID-19, which has significant implications for the study and prevention of psychiatric symptoms in major epidemic diseases.

Colitis reduces active social engagement in mice and is ameliorated by supplementation with human microbiota members

Multiple neurological disorders are associated with gastrointestinal (GI) symptoms, including autism spectrum disorder (ASD). However, it is unclear whether GI distress itself can modify aspects of behavior. Here, we show that mice that experience repeated colitis have impaired active social engagement, as measured by interactions with a foreign mouse, even though signs of colitis were no longer present. We then tested the hypothesis that individuals with ASD harbor a microbiota that might differentially influence GI health by performing microbiota transplantation studies into male germfree animals, followed by induction of colitis. Animals that harbor a microbiota from ASD individuals have worsened gut phenotypes when compared to animals colonized with microbiotas from familial neurotypical (NT) controls. We identify the enrichment of Blautia species in all familial NT controls and observe an association between elevated abundance of Bacteroides uniformis and reductions in intestinal injury. Oral treatment with either of these microbes reduces colon injury in mice. Finally, provision of a Blautia isolate from a NT control ameliorates gut injury-associated active social engagement in mice. Collectively, our data demonstrate that past intestinal distress is associated with changes in active social behavior in mice that can be ameliorated by supplementation of members of the human microbiota.

Microbiota profiling reveals alteration of gut microbial neurotransmitters in a mouse model of autism-associated 16p11.2 microduplication

The gut-brain axis is evident in modulating neuropsychiatric diseases including autism spectrum disorder (ASD). Chromosomal 16p11.2 microduplication 16p11.2dp/+ is among the most prevalent genetic copy number variations (CNV) linked with ASD. However, the implications of gut microbiota status underlying the development of ASD-like impairments induced by 16p11.2dp/+ remains unclear. To address this, we initially investigated a mouse model of 16p11.2dp/+, which exhibits social novelty deficit and repetitive behavior characteristic of ASD. Subsequently, we conducted a comparative analysis of the gut microbial community and metabolomic profiles between 16p11.2dp/+ and their wild-type counterparts using 16S rRNA sequencing and liquid chromatography-mass spectrometry (LC/MS). Our microbiota analysis revealed structural dysbiosis in 16p11.2dp/+ mice, characterized by reduced biodiversity and alterations in species abundance, as indicated by α/β-diversity analysis. Specifically, we observed reduced relative abundances of Faecalibaculum and Romboutsia, accompanied by an increase in Turicibacter and Prevotellaceae UCG_001 in 16p11.2dp/+ group. Metabolomic analysis identified 19 significantly altered metabolites and unveiled enriched amino acid metabolism pathways. Notably, a disruption in the predominantly histamine-centered neurotransmitter network was observed in 16p11.2dp/+ mice. Collectively, our findings delineate potential alterations and correlations among the gut microbiota and microbial neurotransmitters in 16p11.2dp/+ mice, providing new insights into the pathogenesis of and treatment for 16p11.2 CNV-associated ASD.

Donor-recipient intermicrobial interactions impact transfer of subspecies and fecal microbiota transplantation outcome

Studies on fecal microbiota transplantation (FMT) have reported inconsistent connections between clinical outcomes and donor strain engraftment. Analyses of subspecies-level crosstalk and its influences on lineage transfer in metagenomic FMT datasets have proved challenging, as single-nucleotide polymorphisms (SNPs) are generally not linked and are often absent. Here, we utilized species genome bin (SGB), which employs co-abundance binning, to investigate subspecies-level microbiome dynamics in patients with autism spectrum disorder (ASD) who had gastrointestinal comorbidities and underwent encapsulated FMT (Chinese Clinical Trial: 2100043906). We found that interactions between donor and recipient microbes, which were overwhelmingly phylogenetically divergent, were important for subspecies transfer and positive clinical outcomes. Additionally, a donor-recipient SGB match was indicative of a high likelihood of strain transfer. Importantly, these ecodynamics were shared across FMT datasets encompassing multiple diseases. Collectively, these findings provide detailed insight into specific microbial interactions and dynamics that determine FMT success.

Functional contribution of the intestinal microbiome in autism spectrum disorder, attention deficit hyperactivity disorder, and Rett syndrome: a systematic review of pediatric and adult studies

Introduction

Critical phases of neurodevelopment and gut microbiota diversification occur in early life and both processes are impacted by genetic and environmental factors. Recent studies have shown the presence of gut microbiota alterations in neurodevelopmental disorders. Here we performed a systematic review of alterations of the intestinal microbiota composition and function in pediatric and adult patients affected by autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and Rett syndrome (RETT).

Methods

We searched selected keywords in the online databases of PubMed, Cochrane, and OVID (January 1980 to December 2021) with secondary review of references of eligible articles. Two reviewers independently performed critical appraisals on the included articles using the Critical Appraisal Skills Program for each study design.

Results

Our systematic review identified 18, 7, and 3 original articles describing intestinal microbiota profiles in ASD, ADHD, and RETT, respectively. Decreased Firmicutes and increased Bacteroidetes were observed in the gut microbiota of individuals affected by ASD and ADHD. Proinflammatory cytokines, short-chain fatty acids and neurotransmitter levels were altered in ASD and RETT. Constipation and visceral pain were related to changes in the gut microbiota in patients affected by ASD and RETT. Hyperactivity and impulsivity were negatively correlated with Faecalibacterium (phylum Firmicutes) and positively correlated with Bacteroides sp. (phylum Bacteroidetes) in ADHD subjects. Five studies explored microbiota-or diet-targeted interventions in ASD and ADHD. Probiotic treatments with Lactobacillus sp. and fecal microbiota transplantation from healthy donors reduced constipation and ameliorated ASD symptoms in affected children. Perinatal administration of Lactobacillus sp. prevented the onset of Asperger and ADHD symptoms in adolescence. Micronutrient supplementation improved disease symptomatology in ADHD without causing significant changes in microbiota communities' composition.

Discussion

Several discrepancies were found among the included studies, primarily due to sample size, variations in dietary practices, and a high prevalence of functional gastrointestinal symptoms. Further studies employing longitudinal study designs, larger sample sizes and multi-omics technologies are warranted to identify the functional contribution of the intestinal microbiota in developmental trajectories of the human brain and neurobehavior.

Systematic review registration

https://clinicaltrials.gov/, CRD42020158734.

Predispose, precipitate, perpetuate, and protect: how diet and the gut influence mental health in emerging adulthood

Medicine often employs the 4Ps of predisposing, precipitating, perpetuating, and protective factors to identify salient influences on illness states, and to help guide patient care. Mental illness is a significant cause of morbidity and mortality worldwide. Mental health is a complex combination of biological, psychological, environmental, and social factors. There is growing interest in the gut-brain-microbiome (GBM) axis and its impact on mental health. We use the medical model of the 4Ps to explore factors involving the connection between nutrition and the GBM axis and their associated risks with mental health problems in emerging adults (EAs), a life stage when mental illness onset is the most common. We review the impact of current dietary trends on the GBM and on mental health, and the role that gut microbiome-based interventions can have in modulating the GBM axis of EAs. We discuss the implications of gut health on the GBM and areas for clinical intervention.

Autism spectrum disorders and the gastrointestinal tract: insights into mechanisms and clinical relevance

Autism spectrum disorders (ASDs) are recognized as central neurodevelopmental disorders diagnosed by impairments in social interactions, communication and repetitive behaviours. The recognition of ASD as a central nervous system (CNS)-mediated neurobehavioural disorder has led most of the research in ASD to be focused on the CNS. However, gastrointestinal function is also likely to be affected owing to the neural mechanistic nature of ASD and the nervous system in the gastrointestinal tract (enteric nervous system). Thus, it is unsurprising that gastrointestinal disorders, particularly constipation, diarrhoea and abdominal pain, are highly comorbid in individuals with ASD. Gastrointestinal problems have also been repeatedly associated with increased severity of the core symptoms diagnostic of ASD and other centrally mediated comorbid conditions, including psychiatric issues, irritability, rigid-compulsive behaviours and aggression. Despite the high prevalence of gastrointestinal dysfunction in ASD and its associated behavioural comorbidities, the specific links between these two conditions have not been clearly delineated, and current data linking ASD to gastrointestinal dysfunction have not been extensively reviewed. This Review outlines the established and emerging clinical and preclinical evidence that emphasizes the gut as a novel mechanistic and potential therapeutic target for individuals with ASD.

Reply to Ayoub-Charette et al. Lack of Biological Plausibility and Major Methodological Issues Cast Doubt on the Association between Aspartame and Autism. Comment on "Fowler et al. Daily Early-Life Exposures to Diet Soda and Aspartame Are Associated with Autism in Males: A Case-Control Study. Nutrients 2023, 15, 3772"

Thank you for the opportunity to respond to the concerns raised by Ayoub-Charette et al [...].

Differences in gut microbiota between Dutch and South-Asian Surinamese: potential implications for type 2 diabetes mellitus

Gut microbiota, or the collection of diverse microorganisms in a specific ecological niche, are known to significantly impact human health. Decreased gut microbiota production of short-chain fatty acids (SCFAs) has been implicated in type 2 diabetes mellitus (T2DM) disease progression. Most microbiome studies focus on ethnic majorities. This study aims to understand how the microbiome differs between an ethnic majority (the Dutch) and minority (the South-Asian Surinamese (SAS)) group with a lower and higher prevalence of T2DM, respectively. Microbiome data from the Healthy Life in an Urban Setting (HELIUS) cohort were used. Two age- and gender-matched groups were compared: the Dutch (n = 41) and SAS (n = 43). Microbial community compositions were generated via DADA2. Metrics of microbial diversity and similarity between groups were computed. Biomarker analyses were performed to determine discriminating taxa. Bacterial co-occurrence networks were constructed to examine ecological patterns. A tight microbiota cluster was observed in the Dutch women, which overlapped with some of the SAS microbiota. The Dutch gut contained a more interconnected microbial ecology, whereas the SAS network was dispersed, i.e., contained fewer inter-taxonomic correlational relationships. Bacteroides caccae, Butyricicoccus, Alistipes putredinis, Coprococcus comes, Odoribacter splanchnicus, and Lachnospira were enriched in the Dutch gut. Haemophilus, Bifidobacterium, and Anaerostipes hadrus discriminated the SAS gut. All but Lachnospira and certain strains of Haemophilus are known to produce SCFAs. The Dutch gut microbiome was distinguished from the SAS by diverse, differentially abundant SCFA-producing taxa with significant cooperation. The dynamic ecology observed in the Dutch was not detected in the SAS. Among several potential gut microbial biomarkers, Haemophilus parainfluenzae likely best characterizes the ethnic minority group, which is more predisposed to T2DM. The higher prevalence of T2DM in the SAS may be associated with the gut dysbiosis observed.

Gut microbiome and serum amino acid metabolome alterations in autism spectrum disorder

Gut microbiota and their metabolic products might play important roles in regulating the pathogenesis of autism spectrum disorder (ASD). The purpose of this study was to characterize gut microbiota and serum amino acid metabolome profiles in children with ASD. A non-randomized controlled study was carried out to analyze the alterations in the intestinal microbiota and their metabolites in patients with ASD (n = 30) compared with neurotypical controls (NC) (n = 30) by metagenomic sequencing to define the gut microbiota community and liquid chromatography/mass spectrometry (LC/MS) analysis to characterize the metabolite profiles. Compared with children in the NC group, those in the ASD group showed lower richness, higher evenness, and an altered microbial community structure. At the class level, Deinococci and Holophagae were significantly lower in children with ASD compared with TD. At the phylum level, Deinococcus-Thermus was significantly lower in children with ASD compared with TD. In addition, the functional properties (such as galactose metabolism) displayed significant differences between the ASD and NC groups. Five dominant altered species were identified and analyzed (LDA score > 2.0, P < 0.05), including Subdoligranulum, Faecalibacterium_praushitzii, Faecalibacterium, Veillonellaceae, and Rumminococcaceae. The peptides/nickel transport system was the main metabolic pathway involved in the differential species in the ASD group. Decreased ornithine levels and elevated valine levels may increase the risk of ASD through a metabolic pathway known as the nickel transport system. The microbial metabolism in diverse environments was negatively correlated with phascolarctobacterium succinatutens. Our study provides novel insights into compositional and functional alterations in the gut microbiome and metabolite profiles in ASD and the underlying mechanisms between metabolite and ASD.

Between Dysbiosis, Maternal Immune Activation and Autism: Is There a Common Pathway?

Autism spectrum disorder (ASD) is a neuropsychiatric condition characterized by impaired social interactions and repetitive stereotyped behaviors. Growing evidence highlights an important role of the gut-brain-microbiome axis in the pathogenesis of ASD. Research indicates an abnormal composition of the gut microbiome and the potential involvement of bacterial molecules in neuroinflammation and brain development disruptions. Concurrently, attention is directed towards the role of short-chain fatty acids (SCFAs) and impaired intestinal tightness. This comprehensive review emphasizes the potential impact of maternal gut microbiota changes on the development of autism in children, especially considering maternal immune activation (MIA). The following paper evaluates the impact of the birth route on the colonization of the child with bacteria in the first weeks of life. Furthermore, it explores the role of pro-inflammatory cytokines, such as IL-6 and IL-17a and mother's obesity as potentially environmental factors of ASD. The purpose of this review is to advance our understanding of ASD pathogenesis, while also searching for the positive implications of the latest therapies, such as probiotics, prebiotics or fecal microbiota transplantation, targeting the gut microbiota and reducing inflammation. This review aims to provide valuable insights that could instruct future studies and treatments for individuals affected by ASD.

Existing and Future Strategies to Manipulate the Gut Microbiota With Diet as a Potential Adjuvant Treatment for Psychiatric Disorders

Nutrition and diet quality play key roles in preventing and slowing cognitive decline and have been linked to multiple brain disorders. This review compiles available evidence from preclinical studies and clinical trials on the impact of nutrition and interventions regarding major psychiatric conditions and some neurological disorders. We emphasize the potential role of diet-related microbiome alterations in these effects and highlight commonalities between various brain disorders related to the microbiome. Despite numerous studies shedding light on these findings, there are still gaps in our understanding due to the limited availability of definitive human trial data firmly establishing a causal link between a specific diet and microbially mediated brain functions and symptoms. The positive impact of certain diets on the microbiome and cognitive function is frequently ascribed with the anti-inflammatory effects of certain microbial metabolites or a reduction of proinflammatory microbial products. We also critically review recent research on pro- and prebiotics and nondietary interventions, particularly fecal microbiota transplantation. The recent focus on diet in relation to brain disorders could lead to improved treatment outcomes with combined dietary, pharmacological, and behavioral interventions.

Protocol for the Gut Bugs in Autism Trial: a double-blind randomised placebo-controlled trial of faecal microbiome transfer for the treatment of gastrointestinal symptoms in autistic adolescents and adults

INTRODUCTION

Autism (formally autism spectrum disorder) encompasses a group of complex neurodevelopmental conditions, characterised by differences in communication and social interactions. Co-occurring chronic gastrointestinal symptoms are common among autistic individuals and can adversely affect their quality of life. This study aims to evaluate the efficacy of oral encapsulated faecal microbiome transfer (FMT) in improving gastrointestinal symptoms and well-being among autistic adolescents and adults.

METHODS AND ANALYSIS

This double-blind, randomised, placebo-controlled trial will recruit 100 autistic adolescents and adults aged 16-45 years, who have mild to severe gastrointestinal symptoms (Gastrointestinal Symptoms Rating Scale (GSRS) score ≥2.0). We will also recruit eight healthy donors aged 18-32 years, who will undergo extensive clinical screening. Recipients will be randomised 1:1 to receive FMT or placebo, stratified by biological sex. Capsules will be administered over two consecutive days following an overnight bowel cleanse with follow-up assessments at 6, 12 and 26 weeks post-treatment. The primary outcome is GSRS score at 6 weeks. Other assessments include anthropometry, body composition, hair cortisol concentration, gut microbiome profile, urine/plasma gut-derived metabolites, plasma markers of gut inflammation/permeability and questionnaires on general well-being, sleep quality, physical activity, food diversity and treatment tolerability. Adverse events will be recorded and reviewed by an independent data monitoring committee.

ETHICS AND DISSEMINATION

Ethics approval for the study was granted by the Central Health and Disability Ethics Committee on 24 August 2021 (reference number: 21/CEN/211). Results will be published in peer-reviewed journals and presented to both scientific and consumer group audiences.

TRIAL REGISTRATION NUMBER

ACTRN12622000015741.

The role and impact of abnormal vitamin levels in autism spectrum disorders

The prevalence of autism spectrum disorder (ASD), a neurodevelopmental disorder with a predominance of social behavioral disorders, has increased dramatically in various countries in recent decades. The interplay between genetic and environmental factors is believed to underlie ASD pathogenesis. Recent analyses have shown that abnormal vitamin levels in early life are associated with an increased risk of autism. As essential substances for growth and development, vitamins have been shown to have significant benefits for the nervous and immune systems. However, it is unknown whether certain vitamin types influence the emergence or manifestation of ASD symptoms. Several studies have focused on vitamin levels in children with autism, and neurotypical children have provided different insights into the types of vitamins and their intake. Here, we review the mechanisms and significance of several vitamins (A, B, C, D, E, and K) that are closely associated with the development of ASD in order to prevent, mitigate, and treat ASD. Efforts have been made to discover and develop new indicators for nutritional assessment of children with ASD to play a greater role in the early detection of ASD and therapeutic remission after diagnosis.

The correlation between gut microbiota and both neurotransmitters and mental disorders: A narrative review

The gastrointestinal tract is embedded with microorganisms of numerous genera, referred to as gut microbiota. Gut microbiota has multiple effects on many body organs, including the brain. There is a bidirectional connection between the gut and brain called the gut-brain-axis, and these connections are formed through immunological, neuronal, and neuroendocrine pathways. In addition, gut microbiota modulates the synthesis and functioning of neurotransmitters. Therefore, the disruption of the gut microbiota in the composition or function, which is known as dysbiosis, is associated with the pathogenesis of many mental disorders, such as schizophrenia, depression, and other psychiatric disorders. This review aims to summarize the modulation role of the gut microbiota in 4 prominent neurotransmitters (tryptophan and serotonergic system, dopamine, gamma-aminobutyric acid, and glutamate), as well as its association with 4 psychiatric disorders (schizophrenia, depression, anxiety disorders, and autism spectrum disorder). More future research is required to develop efficient gut-microbiota-based therapies for these illnesses.

Effects of fecal microbiota transplantation and fecal virome transplantation on LPS-induced intestinal injury in broilers

The interesting roles and efficiencies of fecal microbiota transplantation (FMT) have attracted considerable attention and have been gradually evidenced in specific animal models. While the growing evidence that bacteriophages play roles in FMT efficacy has attracted considerable interest. In this study, we aimed to explore the effects of FMT and fecal virome transplantation (FVT) in improving inflammatory damage and ileal microbiota disorder in broilers. A total of 224 Arbor Acres broilers were selected at 1-day-old and randomly divided into the following 4 groups, with 56 broilers in each group: the CON group (the negative control group, sterile physiological saline injection + sterile phosphate-buffered saline (PBS) solution gavage), LPS group (the positive control group, lipopolysaccharide (LPS) injection + sterile PBS solution gavage), LPS + FMT group (LPS injection + FMT solution gavage), LPS + FVT group (LPS injection + FVT solution gavage). The results showed that: LPS injection significantly upregulated the mRNA expression levels of IFN-γ (P < 0.05) and IL-8 (P < 0.001) in ileal mucosa of broilers at 11th day of age (D11), while LPS + FMT and LPS + FVT did not; LPS injection significantly upregulated the mRNA expression of ZO-1 in ileal mucosa at D11 (P < 0.01), while LPS + FMT and LPS + FVT did not; at D11, compare to CON group, LPS injection and LPS + FMT significantly increased the relative abundance of virulence factor Rab2 interacting conserved protein A-related genes in broiler ileum contents (P < 0.05), while LPS + FVT had no significant difference with CON group (P > 0.05); at D11, LPS injection significantly downregulated the biosynthesis of antibiotics pathway (P < 0.05) in the ileal contents, while LPS + FVT did not. In conclusion, both FMT and FVT could promote the recovery of inflammation caused by LPS. Furthermore, FVT had shown less disadvantage stimulation on the broilers and could reduce the risk of transmission of pathogenic genes, compared to FMT.

Regulation of the intestinal flora using polysaccharides from Callicarpa nudiflora Hook to alleviate ulcerative colitis and the molecular mechanisms involved

Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) that cannot be completely cured by current treatments. C. nudiflora Hook has antibacterial, anti-inflammatory, and hemostatic biological functions; however, the therapeutic role of C. nudiflora Hook or its extracts in IBD remains poorly understood. In this study, we extracted and purified three fractions of C. nudiflora Hook polysaccharides by hydroalcohol precipitation method, which were named as CNLP-1, CNLP-2 and CNLP-3, respectively. CNLP-2, the main component of the polysaccharides of C. nudiflora Hook is an pyranose type acidic polysaccharide composed of Fuc, Rha, Ara, Gal, Glc, Xyl, Man, Gal-UA and Glc-UA, with an Mn of 15.624 kDa; Mw of 31.375 kDa. CNLP-2 was found to have a smooth lamellar structure as observed by scanning electron microscopy. To investigate the effect of CNLP-2 (abbreviated to CNLP) on dextran sodium sulfate (DSS)-induced UC mice and its mechanism of action, we treated DSS-induced UC mice by administering CNLP at a dose of 100 mg/kg every other day. The results of the study showed that CNLP alleviated the clinical symptoms such as body weight (BW) loss, pathological damage, and systemic inflammation. The mechanism may be through the regulation of intestinal flora and its metabolism, which in turn affects the expression of NF-κB/MAPK pathway-related proteins through the metabolites of intestinal flora to further alleviate inflammation and ultimately improve the intestinal barrier function in UC mice. In conclusion, CNLP has great potential for the treatment of IBD.

Exposure to prescribed medication in early life and impacts on gut microbiota and disease development

The gut microbiota during early life plays a crucial role in infant development. This microbial-host interaction is also essential for metabolism, immunity, and overall human health in later life. Early-life pharmaceutical exposure, mainly referring to exposure during pregnancy, childbirth, and infancy, may change the structure and function of gut microbiota and affect later human health. In this Review, we describe how healthy gut microbiota is established in early life. We summarise the commonly prescribed medications during early life, including antibiotics, acid suppressant medications and other medications such as antidepressants, analgesics and steroid hormones, and discuss how these medication-induced changes in gut microbiota are involved in the pathological process of diseases, including infections, inflammatory bowel disease, metabolic diseases, allergic diseases and neurodevelopmental disorders. Finally, we review some critical methods such as dietary therapy, probiotics, prebiotics, faecal microbiota transplantation, genetically engineered phages, and vagus nerve stimulation in early life, aiming to provide a new strategy for the prevention of adverse health outcomes caused by prescribed medications exposure in early life.

A Double-Blind Randomised Controlled Trial of Prebiotic Supplementation in Children with Autism: Effects on Parental Quality of Life, Child Behaviour, Gastrointestinal Symptoms, and the Microbiome

PURPOSE

Modifying gut bacteria in children with autism may influence behaviour, with potential to improve family functioning. We conducted a randomised controlled trial to assess the effect of prebiotics on behaviour, gastrointestinal symptoms and downstream effects on parental quality of life.

METHOD

Children with autism (4-10yrs) were randomised to 2.4 g/d of prebiotic (GOS) or placebo for six weeks. Pre and post stools samples were collected, and validated questionnaires used to measure change in social and mealtime behaviours, GI symptoms and pQOL. Linear mixed models evaluated group differences for behavioural variables, and Mann Whitney U tests were used to compare change between-groups for GI symptoms, differential abundance of genera and alpha diversity of the microbiome.

RESULTS

Thirty-three parent-child dyads completed the trial. No group difference was seen for behavioural variables but both groups improved significantly from baseline. There was a medium effect size between groups for GI symptoms (d = 0.47) and pQOL (d = 0.44) driven by greater improvements in the prebiotic group. Bifidobacterium increased threefold following prebiotics (1.4-5.9%, p < 0.001) with no change in controls. Supplements were well tolerated, compliance with dose 94%.

CONCLUSION

Prebiotics modify levels of Bifidobacterium and prove well tolerated but in this instance, resulted in only marginal effects on GI symptoms and pQOL. A larger sample of children with more severe symptoms could help to determine the potential of prebiotics in autism.

TRIAL REGISTRATION

https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12619000615189 .

The many faces of microbiota-gut-brain axis in autism spectrum disorder

The gut-brain axis is gaining more attention in neurodevelopmental disorders, especially autism spectrum disorder (ASD). Many factors can influence microbiota in early life, including host genetics and perinatal events (infections, mode of birth/delivery, medications, nutritional supply, and environmental stressors). The gut microbiome can influence blood-brain barrier (BBB) permeability, drug bioavailability, and social behaviors. Developing microbiota-based interventions such as probiotics, gastrointestinal (GI) microbiota transplantation, or metabolite supplementation may offer an exciting approach to treating ASD. This review highlights that RNA sequencing, metabolomics, and transcriptomics data are needed to understand how microbial modulators can influence ASD pathophysiology. Due to the substantial clinical heterogeneity of ASD, medical caretakers may be unlikely to develop a broad and effective general gut microbiota modulator. However, dietary modulation followed by administration of microbiota modulators is a promising option for treating ASD-related behavioral and gastrointestinal symptoms. Future work should focus on the accuracy of biomarker tests and developing specific psychobiotic agents tailored towards the gut microbiota seen in ASD patients, which may include developing individualized treatment options.

The Impact of Cesarean Section Delivery on Intestinal Microbiota: Mechanisms, Consequences, and Perspectives-A Systematic Review

The relationship between cesarean section (CS) delivery and intestinal microbiota is increasingly studied. CS-born infants display distinct gut microbial compositions due to the absence of maternal birth canal microorganisms. These alterations potentially link to long-term health implications like immune-related disorders and allergies. This correlation underscores the intricate connection between birth mode and the establishment of diverse intestinal microbiota. A systematic literature review was conducted on the PubMed, Scopus, and Web of Science databases by analyzing the articles and examining the intricate interactions between CS delivery and the infant's intestinal microbiota. The analysis, based on a wide-ranging selection of studies, elucidates the multifaceted dynamics involved in CS-associated shifts in the establishment of fetal microbiota. We also explore the potential ramifications of these microbial changes on neonatal health and development, providing a comprehensive overview for clinicians and researchers. By synthesizing current findings, this review contributes to a deeper understanding of the interplay between delivery mode and early microbial colonization, paving the way for informed clinical decisions and future investigations in the field of perinatal medicine.

An updated overview on the relationship between human gut microbiome dysbiosis and psychiatric and psychological disorders

There is a lot of evidence establishing that nervous system development is related to the composition and functions of the gut microbiome. In addition, the central nervous system (CNS) controls the imbalance of the intestinal microbiota, constituting a bidirectional communication system. At present, various gut-brain crosstalk routes have been described, including immune, endocrine and neural circuits via the vagal pathway. Several empirical data have associated gut microbiota alterations (dysbiosis) with neuropsychiatric diseases, such as Alzheimer's disease, autism and Parkinson's disease, and with other psychological disorders, like anxiety and depression. Fecal microbiota transplantation (FMT) therapy has shown that the gut microbiota can transfer behavioral features to recipient animals, which provides strong evidence to establish a causal-effect relationship. Interventions, based on prebiotics, probiotics or synbiotics, have demonstrated an important influence of microbiota on neurological disorders by the synthesis of neuroactive compounds that interact with the nervous system and by the regulation of inflammatory and endocrine processes. Further research is needed to demonstrate the influence of gut microbiota dysbiosis on psychiatric and psychological disorders, and how microbiota-based interventions may be used as potential therapeutic tools.

Precision microbial intervention improves social behavior but not autism severity: A pilot double-blind randomized placebo-controlled trial

Autism spectrum disorder (ASD) is characterized by the presence of restricted/repetitive behaviors and social communication deficits. Because effective treatments for ASD remain elusive, novel therapeutic strategies are necessary. Preclinical studies show that L. reuteri selectively reversed social deficits in several models for ASD. Here, in a double-blind, randomized, placebo-controlled trial, we tested the effect of L. reuteri (a product containing a combination of strains ATCC-PTA-6475 and DSM-17938) in children with ASD. The treatment does not alter overall autism severity, restricted/repetitive behaviors, the microbiome composition, or the immune profile. However, L. reuteri combination yields significant improvements in social functioning that generalized across different measures. Interestingly, ATCC-PTA-6475, but not the parental strain of DSM-17938, reverses the social deficits in a preclinical mouse model for ASD. Collectively, our findings show that L. reuteri enhances social behavior in children with ASD, thereby warranting larger trials in which strain-specific effects should also be investigated.

A comparison between children and adolescents with autism spectrum disorders and healthy controls in biomedical factors, trace elements, and microbiota biomarkers: a meta-analysis

Introduction

Autism spectrum disorder (ASD) is a multifaceted developmental condition that commonly appears during early childhood. The etiology of ASD remains multifactorial and not yet fully understood. The identification of biomarkers may provide insights into the underlying mechanisms and pathophysiology of the disorder. The present study aimed to explore the causes of ASD by investigating the key biomedical markers, trace elements, and microbiota factors between children with autism spectrum disorder (ASD) and control subjects.

Methods

Medline, PubMed, ProQuest, EMBASE, Cochrane Library, PsycINFO, Web of Science, and EMBSCO databases have been searched for publications from 2012 to 2023 with no language restrictions using the population, intervention, control, and outcome (PICO) approach. Keywords including "autism spectrum disorder," "oxytocin," "GABA," "Serotonin," "CRP," "IL-6," "Fe," "Zn," "Cu," and "gut microbiota" were used for the search. The Joanna Briggs Institute (JBI) critical appraisal checklist was used to assess the article quality, and a random model was used to assess the mean difference and standardized difference between ASD and the control group in all biomedical markers, trace elements, and microbiota factors.

Results

From 76,217 records, 43 studies met the inclusion and exclusion criteria and were included in this meta-analysis. The pooled analyses showed that children with ASD had significantly lower levels of oxytocin (mean differences, MD = -45.691, 95% confidence interval, CI: -61.667, -29.717), iron (MD = -3.203, 95% CI: -4.891, -1.514), and zinc (MD = -6.707, 95% CI: -12.691, -0.722), lower relative abundance of Bifidobacterium (MD = -1.321, 95% CI: -2.403, -0.238) and Parabacteroides (MD = -0.081, 95% CI: -0.148, -0.013), higher levels of c-reactive protein, CRP (MD = 0.401, 95% CI: 0.036, 0.772), and GABA (MD = 0.115, 95% CI: 0.045, 0.186), and higher relative abundance of Bacteroides (MD = 1.386, 95% CI: 0.717, 2.055) and Clostridium (MD = 0.281, 95% CI: 0.035, 0.526) when compared with controls. The results of the overall analyses were stable after performing the sensitivity analyses. Additionally, no substantial publication bias was observed among the studies.

Interpretation

Children with ASD have significantly higher levels of CRP and GABA, lower levels of oxytocin, iron, and zinc, lower relative abundance of Bifidobacterium and Parabacteroides, and higher relative abundance of Faecalibacterium, Bacteroides, and Clostridium when compared with controls. These results suggest that these indicators may be a potential biomarker panel for the diagnosis or determining therapeutic targets of ASD. Furthermore, large, sample-based, and randomized controlled trials are needed to confirm these results.

Therapeutic efficacy of sulforaphane in autism spectrum disorders and its association with gut microbiota: animal model and human longitudinal studies

Introduction

Sulforaphane (SFN) has been found to alleviate complications linked with several diseases by regulating gut microbiota (GM), while the effect of GM on SFN for autism spectrum disorders (ASD) has not been studied. Therefore, this study aimed to investigate the relationship between the effects of SFN on childhood ASD and GM through animal model and human studies.

Methods

We evaluated the therapeutic effects of SFN on maternal immune activation (MIA) induced ASD-like rat model and pediatric autism patients using three-chamber social test and OSU Autism Rating Scale-DSM-IV (OARS-4), respectively, with parallel GM analysis using 16SrRNA sequencing.

Results

SFN significantly improved the sniffing times of ASD-like rats in the three-chamber test. For human participants, the average verbal or non-verbal communication (OSU-CO) scores of SFN group had changed significantly at the 12-wk endpoint. SFN was safe and no serious side effects after taking. GM changes were similar for both ASD-like rats and ASD patients, such as consistent changes in order Bacillales, family Staphylococcaceae and genus Staphylococcus. Although the gut microbiota composition was significantly altered in SFN-treated ASD-like rats, the alteration of GM was not evident in ASD patients after 12 weeks of SFN treatment. However, in the network analysis, we found 25 taxa correlated with rats' social behavior, 8 of which were associated with SFN treatment in ASD-like rats, For ASD patients, we found 35 GM abundance alterations correlated with improvements in ASD symptoms after SFN treatment. Moreover, family Pasteurellaceae and genus Haemophilus were found to be associated with SFN administration in the network analyses in both ASD-like rats and ASD patients.

Discussion

These findings suggest that SFN could provide a novel avenue for preventing and treating ASD, and its therapeutic effects might be related to gut microbiota.

Advances in the Treatment of Autism Spectrum Disorder: Current and Promising Strategies

Autism spectrum disorder (ASD) is an umbrella term for developmental disorders characterized by social and communication impairments, language difficulties, restricted interests, and repetitive behaviors. Current management approaches for ASD aim to resolve its clinical manifestations based on the type and severity of the disability. Although some medications like risperidone show potential in regulating ASD-associated symptoms, a comprehensive treatment strategy for ASD is yet to be discovered. To date, identifying appropriate therapeutic targets and treatment strategies remains challenging due to the complex pathogenesis associated with ASD. Therefore, a comprehensive approach must be tailored to target the numerous pathogenetic pathways of ASD. From currently viable and basic treatment strategies, this review explores the entire field of advancements in ASD management up to cutting-edge modern scientific research. A novel systematic and personalized treatment approach is suggested, combining the available medications and targeting each symptom accordingly. Herein, summarize and categorize the most appropriate ways of modern ASD management into three distinct categories: current, promising, and prospective strategies.

Children autism spectrum disorder and gut microbiota: A bibliometric and visual analysis from 2000 to 2023

Autism spectrum disorder (ASD) has evolved from a narrow and rare childhood-onset disorder to a widely publicized and researched lifelong disease recognized as common and significantly heterogeneous. Researchers have suggested that gastrointestinal symptoms in ASD may be a manifestation of an underlying inflammatory process. However, there is a lack of bibliometric analysis of ASD and gut microbiota in children. Accordingly, this study conducts a bibliometric analysis of ASD and gut microbiota in children from 2000 to 2023, explores the current status and cutting-edge trends in the field of ASD and gut microbiota in children, and identifies new directions for future research. The literature on ASD and gut microbiota in children was screened using the Web of Science Core Collection from 2000 to 2023. Annual publications, countries, institutions, authors, journals, keywords, and references were visualized and analyzed using CiteSpace 5.8. R3 and VOSviewer1.6.18. This study included 1071 publications. Since the beginning of 2011, the overall number of articles shows an upward trend. The most productive country and institution are the United States and the University of California system, respectively. The most frequently cited author is Kang Dae-Wook, with 790 citations, who has contributed significantly to this field. Timothy Dinan is the most prolific author, with 34 articles. The journal with the most published articles on this topic is Nutrients, whereas PLOS One is the most cited journal. The most used keyword is "gut microbiota," and the reference for the highest outbreak intensity is Hsiao. The research hotspots and trends predicted in this study provide a reference for further in-depth research in this field.

[Gut Microbiota and Autism Spectrum Disorders: An Overview of Correlations and Potential Implications for Therapeutic Interventions]

Gut Microbiota and Autism Spectrum Disorders: An Overview of Correlations and Potential Implications for Therapeutic Interventions Abstract: At the beginning of research on microbiota, researchers focused mainly on the role of microbiota dysbiosis in the development of gastrointestinal diseases. However, over the last years, researchers have also identified correlations with other physical processes and neuropsychiatric diseases such as autism spectrum disorder. These correlations are believed to be at least partly mediated through the brain-gut-microbiome axis. An altered composition of microbiota in patients with autism spectrum disorder was detected compared to healthy controls. Today, the discussion centers around a possible systemic impact of the metabolites of some microbiota or microbiota-induced chronic inflammatory processes on the brain (mediated through the brain-gut-microbiome axis) as an underlying mechanism. Still, the specific underlying mechanisms remain largely unknown, so conclusions on therapeutic implications are difficult to determine. Here, we describe some promising approaches to improving autistic behavior through dietary changes, the use of prebiotics and probiotics, stool transplantation from healthy controls, and restricted absorbance of certain metabolites. We need further clinical studies of high quality to fully understand the pathophysiology of autism spectrum disorder and to improve diagnostic and therapeutic strategies.

Twnbiome: a public database of the healthy Taiwanese gut microbiome

With new advances in next generation sequencing (NGS) technology at reduced costs, research on bacterial genomes in the environment has become affordable. Compared to traditional methods, NGS provides high-throughput sequencing reads and the ability to identify many species in the microbiome that were previously unknown. Numerous bioinformatics tools and algorithms have been developed to conduct such analyses. However, in order to obtain biologically meaningful results, the researcher must select the proper tools and combine them to construct an efficient pipeline. This complex procedure may include tens of tools, each of which require correct parameter settings. Furthermore, an NGS data analysis involves multiple series of command-line tools and requires extensive computational resources, which imposes a high barrier for biologists and clinicians to conduct NGS analysis and even interpret their own data. Therefore, we established a public gut microbiome database, which we call Twnbiome, created using healthy subjects from Taiwan, with the goal of enabling microbiota research for the Taiwanese population. Twnbiome provides users with a baseline gut microbiome panel from a healthy Taiwanese cohort, which can be utilized as a reference for conducting case-control studies for a variety of diseases. It is an interactive, informative, and user-friendly database. Twnbiome additionally offers an analysis pipeline, where users can upload their data and download analyzed results. Twnbiome offers an online database which non-bioinformatics users such as clinicians and doctors can not only utilize to access a control set of data, but also analyze raw data with a few easy clicks. All results are customizable with ready-made plots and easily downloadable tables. Database URL: http://twnbiome.cgm.ntu.edu.tw/ .