Fecal Microbiota Transplantation: a Future Therapeutic Option for Obesity/Diabetes?

Obesity and its treatment: Toward new approaches

Obesity has until now been defined in terms of body mass index, a parameter which lacks sensitivity. The definition rather needs to take account of the pathophysiology and impact of the mechanical, metabolic and psychological complications associated with excess adiposity, as proposed by the French Health Authority in 2022. Initial phenotyping of pathophysiological determinants and complications make it possible to precisely define treatment objectives and the means used to achieve them. For example, excess adiposity is associated with hypervolemia, which increases the risk of heart failure independently of classic cardiovascular risk factors, due in particular to myocardial remodeling and diastolic dysfunction. In this indication, SGLT2 (sodium/glucose cotransporter 2) inhibitors may be relevant. A global approach, involving assessment of eating behavior and sensations, energy expenditure and emotional eating, enables us to identify drug treatments suited to each profile. Obesity is a recurrent pathology requiring the development of new combined or sequential drug treatments. Currently under development, inhibitors of the myostatin/activin A pathway conserve lean body mass during weight loss, a crucial factor in limiting weight regain and maintaining functional capacity. Beyond medical or surgical approaches to obesity, lifelong lifestyle interventions are central to improving quality of life and limiting the risks associated with excess adiposity.

Fecal microbiota transplantation mitigates postdieting weight regain in mice by modulating the gut-liver axis

BACKGROUND

Dysbiosis of the microbiome is strongly associated with weight rebound after dieting. However, the interactions between the host and microbiome and their relevance to the pathogenesis of post-diet weight rebound remain unclear.

PURPOSE

This study aimed to evaluate the effects of fecal microbiota transplantation (FMT) on post-diet weight regain and to investigate the underlying mechanisms by which FMT inhibits weight regain.

METHODS

FMT was administered once daily to mice for 5 weeks. Gas chromatography tandem mass spectrometry was employed to analyze short-chain fatty acid levels in serum, ultrahigh-performance liquid chromatography tandem mass spectrometry was utilized for analyzing hepatic lipid metabolites, and shotgun metagenomic sequencing was applied to examine the intestinal microbiome.

RESULTS

FMT reduced weight regain and prevented lipid accumulation in both liver and adipose tissue while also improving glucose intolerance in mice. Furthermore, FMT increased the abundance of Enterorhabdus caecimuris and decreased the abundances of Burkholderiales, Sutterellaceae, Turicimonas muris, Bacteroides stercorirosoris, and Acetivibrio ethanolgignens within the gut microbiota. Additionally, elevated propionic acid levels and significant alterations in hepatic lipid metabolites were observed following FMT administration.

CONCLUSIONS

Our findings demonstrate that FMT effectively mitigates post-diet weight regain and associated complications. These effects are mediated through interactions between the gut microbiota and the liver via the gut-propionic acid-liver axis.

CLINICAL TRIAL NUMBER

Not applicable.

Targeted gut microbiome therapy: Applications and prospects of probiotics, fecal microbiota transplantation and natural products in the management of type 2 diabetes

Type 2 diabetes mellitus (T2DM) is considered as one of the most pressing public health challenges worldwide. Studies have shown significant differences in the gut microbiota between healthy individuals and T2DM patients, suggesting that gut microorganisms may play a key role in the onset and progression of T2DM. This review systematically summarizes the relationship between gut microbiota and T2DM, and explores the mechanisms through which gut microorganisms may alleviate T2DM. Additionally, it evaluates the potential of probiotics, fecal microbiota transplantation (FMT)/virome transplantation (FVT), and natural products in modulating gut microbiota to treat T2DM. Although existing studies have suggested that these interventions may delay or even halt the progression of T2DM, most research remained limited to animal models and observational clinical studies, with a lack of high-quality clinical data. This has led to an imbalance between theoretical research and clinical application. Although some studies have explored the regulatory role of the gut virome on the gut microbiota, research in this area remains in its early stages. Based on these current studies, future research should be focused on large-scale, long-term clinical studies and further investigation on the potential role of the gut virome in T2DM. In conclusion, this review aims to summarize the current evidence and explore the applications of gut microbiota in T2DM treatment, as well as providing recommendations for further investigation in this field.

Analysis of influencing factors of washed microbiota transplantation in treating patients with metabolic syndrome

Background and aims

Metabolic Syndrome (MS) is a cluster of metabolic abnormalities closely associated with hypertension, diabetes, hyperlipidemia, obesity, etc. Our previous research indicated that fecal microbiota transplantation (FMT) could improve MS, but the factors influencing the efficacy of washed microbiota transplantation (WMT) in treating MS patients remain unclear. The objective of this study is to analyze the influencing factors of WMT in treating MS patients.

Methods

The clinical data and influencing factors related to MS patients were collected retrospectively. Not only the changes in body mass index [BMI = weight (kg)/height (m)2], blood glucose, blood lipids, and blood pressure were analyzed, but also the influencing factors of WMT in treating MS patients were carried out based on Logistic Regression. The 16S rRNA gene amplicon sequencing was performed on fecal samples before and after WMT treatment.

Results

A total of 210 patients were included, including 68 patients in the WMT group and 142 patients in the drug treatment (DT) group. WMT had a significant improvement and ASCVD downregulation effect on MS patients, and 42.65% of MS patients removed the label of MS after WMT treatment. Independent influencing factors for treating MS patients through WMT include age < 60 years old, high smoking index, infection, single donor selection, single-course WMT treatment, and having hypertension, diabetes, or obesity. WMT treated MS patients by maintaining the balance of gut microbiota.

Conclusions

WMT has a significant effect in improving MS and downregulating ASCVD risk stratification. The therapeutic effect of WMT on MS patients is closely related to their age, smoking index, infection, chronic disease status, donor type, and WMT courses. Therefore, we can improve the efficacy of WMT by reducing independent influencing factors that affect gut microbiota homeostasis.

Diabetes and gut microbiome

Diabetes mellitus represents a significant global health problem. The number of people suffering from this metabolic disease is constantly rising and although the incidence is heterogeneous depending on region, country, economic situation, lifestyle, diet and level of medical care, it is increasing worldwide, especially among youths and children, mainly due to lifestyle and environmental changes. The pathogenesis of the two most common subtypes of diabetes mellitus, type 1 (T1DM) and type 2 (T2DM), is substantially different, so each form is characterized by a different causation, etiology, pathophysiology, presentation, and treatment. Research in recent decades increasingly indicates the potential role of the gut microbiome in the initiation, development, and progression of this disease. Intestinal microbes and their fermentation products have an important impact on host metabolism, immune system, nutrient digestion and absorption, gut barrier integrity and protection against pathogens. This review summarizes the current evidence on the changes in gut microbial populations in both types of diabetes mellitus. Attention is focused on changes in the abundance of specific bacterial groups at different taxonomic levels in humans, and microbiome shift is also assessed in relation to geographic location, age, diet and antidiabetic drug. The causal relationship between gut bacteria and diabetes is still unclear, and future studies applying new methodological approaches to a broader range of microorganisms inhabiting the digestive tract are urgently needed. This would not only provide a better understanding of the role of the gut microbiome in this metabolic disease, but also the use of beneficial bacterial species in the form of probiotics for the treatment of diabetes.

Fecal Microbiota Transplantation as an Alternative Method in the Treatment of Obesity

Fecal microbiota transplantation (FMT) has emerged as a promising therapeutic approach for various health conditions, particularly obesity and metabolic disorders. This review examines the mechanisms underlying FMT, including its role in restoring gut microbiota diversity and enhancing immunomodulatory functions, which are essential for maintaining overall health. Recent studies indicate that FMT can significantly improve body weight and metabolic parameters, suggesting its potential as an alternative or complementary treatment to current obesity therapies. However, the effectiveness of FMT depends on several factors, including the composition of the donor microbiota, recipient characteristics, and concomitant medications or dietary interventions. Despite its great promise, challenges such as standardized protocols, donor screening, and the need for a deeper understanding of gut microbiota dynamics remain key hurdles. Future research should focus on elucidating the specific microbial compositions necessary for optimal therapeutic outcomes and exploring personalized FMT approaches tailored to individual patient profiles. This evolving field presents exciting opportunities for innovative strategies in obesity treatment, warranting further investigation and clinical application.

Gut and intraocular fluid dysbiosis in people with type 2 diabetes-related retinopathy in India: A case for further research

PURPOSE

To explore the relationship between gut microbiome, gut mycobiome, and intraocular (aqueous humor) microbiome dysbiosis in people with type 2 diabetes (T2DM) and diabetic retinopathy (DR).

DESIGN

Multiple case-control studies.

METHODS

We evaluated three groups of people: healthy controls (HC), people with T2DM without retinopathy, and those with DR. The study samples included fecal matter (30-50 g) and aqueous humor (0.05-0.1 mL). After amplicon sequencing, we analyzed microbiome profiles (V3-V4 region of bacterial 16S rRNA gene) and mycobiome (ITS2 region of fungal rRNA gene). The main outcome measures were relative abundance, α and β diversity, and dysbiotic bacteria and fungi, analyzed based on the inferred functions of the taxa.

RESULTS

We recruited 82 people for gut microbiome (30 HC, 24 DM, and 28 DR); 75 people for gut mycobiome (30 HC, 21 DM, and 24 DR); and 12 people for aqueous humor microbiome (4 each HC, DM, and DR) studies. Generally, there was an increased abundance of pro-inflammatory and pathogenic microorganisms and a decreased abundance of anti-inflammatory and probiotic microorganisms. The differences were higher between HC and DM/DR than between DM and DR. In aqueous humor, there was a wider separation in microbiome profiles of people with DR than their gut microbiome.

CONCLUSION

The gut and aqueous humor microbiota of people with diabetes and DR may differ from those without diabetes. Given these unique observations in individuals living in one region of India, further research involving people from different regions is required to identify indices for possible regional or global use.

An Analysis of the Digestive and Reproductive Tract Microbiota in Infertile Women with Obesity

Previous studies have linked the microbiome of distinct body habitats to obesity and infertility; however, the often-divergent results observed have left the role of the so-called "second genome" in obese infertile patients incompletely explored. Here, we present a prospective observational multicenter study of oral, gut, endometrial, and vaginal microbiota of infertile patients classified according to BMI. Patients collected saliva/fecal samples, while vaginal/endometrial fluid samples were collected in the clinic. Total bacterial DNA was extracted, and microbiota profiles were analyzed by 16S rRNA gene sequencing. Our results showed no differences in the Bacteroidetes/Firmicutes ratio (proposed obesity hallmark) in the gut microbiota between patients with obesity and normal weight; however, a tendency for higher levels of genera such as Escherichia-Shigella in normal-weight patients was observed; in comparison, patients with obesity possessed increased numbers of Parasutterella and Roseburia. In the reproductive tract, vaginal samples possessed a similar microbiota to endometrial fluid, both largely colonised by Lactobacillus, Gardnerella, and Streptococcus, supporting the hypothesis that uterine colonisation proceeds from vaginal bacteria ascension. Additionally, higher prevalence of a Streptococcus-dominated (>50%) endometrial microbiota was observed among patients with obesity. This first description of the human digestive and reproductive tract microbiota in infertile women with obesity may explain their poor reproductive outcomes.

The Role of Gut Microbiota in the Onset and Progression of Obesity and Associated Comorbidities

Obesity, a global public health problem, is constantly increasing, so the concerns in preventing and combating it are increasingly focused on the intestinal microbiota. It was found that the microbiota is different in lean people compared to obese individuals, but the exact mechanisms by which energy homeostasis is influenced are still incompletely known. Numerous studies show the involvement of certain bacterial species in promoting obesity and associated diseases such as diabetes, hypertension, cancer, etc. Our aim is to summarize the main findings regarding the influence of several factors such as lifestyle changes, including diet and bariatric surgery, on the diversity of the gut microbiota in obese individuals. The second purpose of this paper is to investigate the potential effect of various microbiota modulation techniques on ameliorating obesity and its comorbidities. A literature search was conducted using the PubMed database, identifying articles published between 2019 and 2024. Most studies identified suggest that obesity is generally associated with alterations of the gut microbiome such as decreased microbial diversity, an increased Firmicutes-to-Bacteroidetes ratio, and increased SCFAs levels. Our findings also indicate that gut microbiota modulation techniques could represent a novel strategy in treating obesity and related metabolic diseases. Although some mechanisms (e.g., inflammation or hormonal regulation) are already considered a powerful connection between gut microbiota and obesity development, further research is needed to enhance the knowledge on this particular topic.

Roseburia intestinalis: A possible target for vascular calcification

With the advancement of metagenomics and metabolomics techniques, the crucial role of the gut microbiome in intestinal, cardiovascular, and metabolic disorders has been extensively explored. Vascular calcification (VC) is common in atherosclerosis, hypertension, diabetes mellitus, and chronic kidney disease. Moreover, it is a significant cause of cardiovascular diseases and mortality. Roseburia intestinalis, as a promising candidate for the next generation of probiotics, plays a substantial role in inhibiting the systemic inflammatory response and holds great potential in the treatment of intestinal diseases, cardiovascular diseases, and metabolic disorders. Its primary metabolite, butyrate, acts on specific receptors (GPR43, GPR41, GPR109a). It enters cells via transporters (MCT1, SMCT1), affecting gene expression through HDACs, PPARγ and Nrf2, promoting energy metabolism and changing the concentration of other metabolites (including AGEs, LPS, BHB) in the circulation to affect the body's life activities. In this paper, we focus on the possible mechanism of the primary metabolite butyrate of Roseburia intestinalis in inhibiting VC, which may become a potential therapeutic target for the treatment of VC and the ways to enhance its effect.

Periodontal bacteria influence systemic diseases through the gut microbiota

Many systemic diseases, including Alzheimer disease (AD), diabetes mellitus (DM) and cardiovascular disease, are associated with microbiota dysbiosis. The oral and intestinal microbiota are directly connected anatomically, and communicate with each other through the oral-gut microbiome axis to establish and maintain host microbial homeostasis. In addition to directly, periodontal bacteria may also be indirectly involved in the regulation of systemic health and disease through the disturbed gut. This paper provides evidence for the role of periodontal bacteria in systemic diseases via the oral-gut axis and the far-reaching implications of maintaining periodontal health in reducing the risk of many intestinal and parenteral diseases. This may provide insight into the underlying pathogenesis of many systemic diseases and the search for new preventive and therapeutic strategies.

Safety and efficacy of fecal microbiota transplantation for viral diseases: A systematic review of clinical trials

BACKGROUND

Gut microbiota play important roles in several diseases like viral infections. In this systematic review, our objective was to assess the efficacy and safety of fecal microbiota transplantation (FMT) in treating various viral diseases.

METHODS

We conducted searches on databases including PubMed, Web of Science, Scopus, and Google Scholar until November 2023. Clinical trials reported outcomes related to safety of FMT or its efficacy in patients with viral diseases were included. We excluded other types of studies that enrolled healthy individuals or patients with other disorders and did not use FMT. The assessment of bias risk was conducted using the National Institutes of Health (NIH) study quality evaluation tool.

RESULTS

Eight studies with total 196 participants were included. Viral diseases were human immunodeficiency virus (HIV), hepatitis B, COVID-19 and Clostridioides difficile coinfection, and cytomegalovirus colitis. In hepatitis B cases, HBeAg clearance was significant in those received FMT (p<0.01), while it was not significant in another one (p = 0.19). A clinical response was noted in 37.5% of patients with cytomegalovirus colitis, with an equal percentage achieving clinical remission post-FMT. There was a significant reduction in Clostridioides difficile relapse rate in FMT group than controls in coinfection of Clostridioides difficile and COVID-19 (2.17% vs. 42.5%, p<0.05). In patients with HIV, partial engraftment of the donor microbiome and increases in alpha diversity were observed after FMT. No severe adverse events were reported. Most studies had fair or good qualities.

CONCLUSIONS

Our findings revealed FMT as a promising, safe treatment for some viral diseases. It improved viral clearance, clinical outcomes, and inflammation. However, the varying responses and small sample sizes call for more trials on FMT in viral diseases.

The complex link between the gut microbiome and obesity-associated metabolic disorders: Mechanisms and therapeutic opportunities

Microbial interactions are widespread and important processes that support the link between disease and microbial ecology. The gut microbiota is a major source of microbial stimuli that can have detrimental or beneficial effects on human health. It is also an endocrine organ that maintains energy homeostasis and host immunity. Obesity is a highly and increasingly prevalent metabolic disease and the leading cause of preventable death worldwide. An imbalance in the gut microbiome is associated with several diseases including obesity-related metabolic disorders. This review summarizes the complex association between the gut microbiome and obesity-associated metabolic diseases and validates the role and mechanisms of ecological dysregulation in the gut in obesity-associated metabolic disorders. Therapies that could potentially alleviate obesity-associated metabolic diseases by modulating the gut microbiota are discussed.

Tauroursodeoxycholic Acid Improves Nonalcoholic Fatty Liver Disease by Regulating Gut Microbiota and Bile Acid Metabolism

Tauroursodeoxycholic acid (TUDCA) is a synthetic bile salt that has demonstrated efficacy in the management of hepatobiliary disorders. However, its specific mechanism of action in preventing and treating nonalcoholic fatty liver disease (NAFLD) remains incompletely understood. This research revealed that TUDCA treatment can reduce obesity and hepatic lipid buildup, enhance intestinal barrier function and microbial balance, and increase the presence of Allobaculum and Bifidobacterium in NAFLD mouse models. TUDCA can influence the activity of farnesoid X receptor (FXR) and cholesterol 7α-hydroxylase (CYP7A1), resulting in higher hepatic bile acid levels and increased expression of sodium taurocholate cotransporting polypeptide (NTCP), leading to elevated concentrations of liver-bound bile acids in mice. Furthermore, TUDCA can inhibit the expression of FXR and fatty acid transport protein 5 (FATP5), thereby reducing fatty acid absorption and hepatic lipid accumulation. This investigation provides new insights into the potential of TUDCA for preventing and treating NAFLD.

The Role of Fecal Microbiota Transplantation (FMT) in the Management of Metabolic Diseases in Humans: A Narrative Review

The gut microbiota represents a complex ecosystem of trillions of microorganisms residing in the human gastrointestinal tract, which is known to interact with the host physiology and regulate multiple functions. Alterations in gut microbial composition, diversity, and function are referred to as dysbiosis. Dysbiosis has been associated with a variety of chronic diseases, including Clostridioides difficile infections, but also cardiometabolic diseases, including obesity, metabolic syndrome, and type 2 diabetes mellitus (T2DM). The implication of gut microbiota dysbiosis in the pathogenesis of both obesity and T2DM has paved the way to implementing novel therapeutic approaches for metabolic diseases through gut microbial reconfiguration. These interventions include probiotics, prebiotics, and synbiotics, while a more innovative approach has been fecal microbiota transplantation (FMT). FMT is a procedure that delivers healthy human donor stool to another individual through the gastrointestinal tract, aiming to restore gut microbiota balance. Several studies have investigated this approach as a potential tool to mitigate the adverse metabolic effects of gut microbiota aberrations associated with obesity and T2DM. The aim of the present review was to critically summarize the existing evidence regarding the clinical applications of FMT in the management of obesity and T2DM and provide an update on the potential of this method to remodel the entire host microbiota, leading thus to weight loss and sustained metabolic benefits. Safety issues, long-term efficacy, limitations, and pitfalls associated with FMT studies are further discussed, emphasizing the need for further research and standardization in certain methodological aspects in order to optimize metabolic outcomes.

Molecular Mechanisms behind Obesity and Their Potential Exploitation in Current and Future Therapy

Obesity is a chronic disease caused primarily by the imbalance between the amount of calories supplied to the body and energy expenditure. Not only does it deteriorate the quality of life, but most importantly it increases the risk of cardiovascular diseases and the development of type 2 diabetes mellitus, leading to reduced life expectancy. In this review, we would like to present the molecular pathomechanisms underlying obesity, which constitute the target points for the action of anti-obesity medications. These include the central nervous system, brain-gut-microbiome axis, gastrointestinal motility, and energy expenditure. A significant part of this article is dedicated to incretin-based drugs such as GLP-1 receptor agonists (e.g., liraglutide and semaglutide), as well as the brand new dual GLP-1 and GIP receptor agonist tirzepatide, all of which have become "block-buster" drugs due to their effectiveness in reducing body weight and beneficial effects on the patient's metabolic profile. Finally, this review article highlights newly designed molecules with the potential for future obesity management that are the subject of ongoing clinical trials.

Konjac supplementation can alleviate obesity induced by high-fat diet in mice by modulating gut microbiota and its metabolites

As a multi-factorial disease, obesity has become one of the major health problems in the world, and it is still increasing rapidly. Konjac supplementation, as a convenient dietary therapy, has been shown to be able to regulate gut microbiota and improve obesity. However, the specific mechanism by which konjac improves obesity through gut microbiota remains to be studied. In this study, a high-fat diet (HFD) was used to induce a mouse obesity model, and 16S rDNA sequencing and an untargeted metabolomics were used to investigate the impact of konjac on gut microbiota and gut metabolites in HFD-induced obese mice. The results show that konjac can reduce the body weight, adipose tissue weight, and lipid level of high-fat diet induced obese mice by changing the gut microbiota structure and gut metabolic profile. Association analysis revealed that konjac supplementation induced changes in gut microbiota, resulting in the up-regulation of 7-dehydrocholesterol and trehalose 6-phosphate, as well as the down-regulation of glycocholic acid and ursocholic acid within the Secondary bile acid biosynthesis pathway, ultimately leading to improvements in obesity. Among them, g_Acinetobacter (Greengene ID: 911888) can promote the synthesis of 7-dehydrocholesterol by synthesizing ERG3. g_Allobaculum (Greengene ID: 271516) and g_Allobaculum (Greengene ID: 259370) can promote the breakdown of trehalose 6-phosphate by synthesizing glvA. Additionally, the down-regulation of glycocholic acid and ursocholic acid may be influenced by the up-regulation of Lachnospiraceae_NK4A136_group. In conclusion, konjac exerts an influence on gut metabolites through the regulation of gut microbiota, thereby playing a pivotal role in alleviating obesity induced by a high-fat diet.

Washed Microbiota Transplantation Is Associated With Improved Lipid Profiles: Long-Term Efficacy and Safety in an Observational Cohort From South China

INTRODUCTION

Dyslipidemia is one of the main risk factors of chronic metabolic diseases. Our previous studies have shown that washed microbiota transplantation (WMT) has a significant improvement effect on patients with hyperlipidemia and hypolipemia in the Chinese population. The purpose of this study was to further explore the long-term efficacy and safety of WMT in patients with hyperlipidemia.

METHODS

Clinical data of patients who received WMT for multicourse were collected. Changes of blood lipid indexes before and after WMT, including triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), lipoprotein A, and Apolipoprotein B.

RESULTS

A total of 124 patients were enrolled, including 56 cases in the hyperlipidemia group and 68 cases with normal lipids. The mean observation time was 787.80 ± 371.45 days, and the longest follow-up time was 1,534 days. TC and non-HDL-C in the hyperlipidemia group with 1-4 courses of WMT were significantly reduced ( P < 0.05); TG decreased significantly after the second course ( P < 0.05); low-density lipoprotein cholesterol also significantly decreased after the fourth course of treatment ( P < 0.05); TG, TC, and non-HDL-C significantly decreased in single course, double course, and multiple course, respectively ( P < 0.05). In terms of time period, over 1 year, the improvement in multicourse treatment was more significant than the single and double-course ones. In terms of comprehensive efficacy, WMT restored 32.14% of patients in the hyperlipidemia group to the normal lipid group ( P < 0.001), of which 30.00% recovered to the normal lipid group within 1 year ( P = 0.004) and 65.38% were reassigned to the normal lipid group over 1 year ( P = 0.003). In addition, over the 1-year treatment period, WMT significantly degraded the high-risk and medium-risk groups of atherosclerotic cardiovascular disease risk stratification in hyperlipidemia cases. There were no serious adverse events.

DISCUSSION

WMT had a long-term improvement effect on patients with hyperlipidemia. The effect of multiple courses over 1 year was more significant than that of single/double courses and also had a significant destratification effect on the risk of atherosclerotic cardiovascular disease with high safety. Therefore, WMT provides a safe and long-term effective clinical treatment for patients with dyslipidemia.

Gluco-regulation & type 2 diabetes: entrenched misconceptions updated to new governing principles for gold standard management

Our understanding of type 2 diabetes (T2D) has evolved dramatically. Advances have upended entrenched dogmas pertaining to the onset and progression of T2D, beliefs that have prevailed from the early era of diabetes research-and continue to populate our medical textbooks and continuing medical education materials. This review article highlights key insights that lend new governing principles for gold standard management of T2D. From the historical context upon which old beliefs arose to new findings, this article outlines evidence and perspectives on beta cell function, the underlying defects in glucoregulation, the remediable nature of T2D, and, the rationale supporting the shift to complication-centric prescribing. Practical approaches translate this rectified understanding of T2D into strategies that fill gaps in current management practices of prediabetes through late type 2 diabetes.

Gut microbiota in insulin resistance: a bibliometric analysis

Background

Insulin resistance (IR) is considered the pathogenic driver of diabetes, and can lead to obesity, hypertension, coronary artery disease, metabolic syndrome, and other metabolic disorders. Accumulating evidence indicates that the connection between gut microbiota and IR. This bibliometric analysis aimed to summarize the knowledge structure of gut microbiota in IR.

Methods

Articles and reviews related to gut microbiota in IR from 2013 to 2022 were retrieved from the Web of Science Core Collection (WoSCC), and the bibliometric analysis and visualization were performed by Microsoft Excel, Origin, R package (bibliometrix), Citespace, and VOSviewer.

Results

A total of 4 749 publications from WoSCC were retrieved, including 3 050 articles and 1 699 reviews. The majority of publications were from China and USA. The University Copenhagen and Shanghai Jiao Tong University were the most active institutions. The journal of Nutrients published the most papers, while Nature was the top 1 co-cited journal, and the major area of these publications was molecular, biology, and immunology. Nieuwdorp M published the highest number of papers, and Cani PD had the highest co-citations. Keyword analysis showed that the most frequently occurring keywords were "gut microbiota", "insulin-resistance", "obesity", and "inflammation". Trend topics and thematic maps showed that serum metabolome and natural products, such as resveratrol, flavonoids were the research hotspots in this field.

Conclusion

This bibliometric analysis summarised the hotspots, frontiers, pathogenesis, and treatment strategies, providing a clear and comprehensive profile of gut microbiota in IR.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01342-x.

Advances in fecal microbiota transplantation for the treatment of diabetes mellitus

Diabetes mellitus (DM) refers to a group of chronic diseases with global prevalence, characterized by persistent hyperglycemia resulting from various etiologies. DM can harm various organ systems and lead to acute or chronic complications, which severely endanger human well-being. Traditional treatment mainly involves controlling blood sugar levels through replacement therapy with drugs and insulin; however, some patients still find a satisfactory curative effect difficult to achieve. Extensive research has demonstrated a close correlation between enteric dysbacteriosis and the pathogenesis of various types of DM, paving the way for novel therapeutic approaches targeting the gut microbiota to manage DM. Fecal microbiota transplantation (FMT), a method for re-establishing the intestinal microbiome balance, offers new possibilities for treating diabetes. This article provides a comprehensive review of the correlation between DM and the gut microbiota, as well as the current advancements in FMT treatment for DM, using FMT as an illustrative example. This study aims to offer novel perspectives and establish a theoretical foundation for the clinical diagnosis and management of DM.

Lead exposure aggravates glucose metabolism disorders through gut microbiota dysbiosis and intestinal barrier damage in high-fat diet-fed mice

BACKGROUND

Lead (Pb) is an ancient toxic metal and is still a major public health issue. Our previous study found that Pb exposure promotes metabolic disorders in obese mice, but the molecular mechanisms remain unclear. The present study explored the effects of Pb exposure on glucose homeostasis in mice fed a normal diet (ND) and high-fat diet (HFD) from the perspective of gut microbiota.

RESULTS

Pb exposure had little effect on glucose metabolism in ND mice, but exacerbated hyperglycemia and insulin resistance, and impaired glucose tolerance in HFD mice. Pb exposure impaired intestinal tight junctions and mucin expression in HFD mice, increasing intestinal permeability and inflammation. Moreover, Pb exposure altered the composition and structure of the gut microbiota and decreased short-chain fatty acids (SCFAs) levels in HFD mice. Correlation analysis revealed that the gut microbiota and SCFAs were significantly correlated with the gut barrier and glucose homeostasis. Furthermore, the fecal microbiota transplantation from Pb-exposed HFD mice resulted in glucose homeostasis imbalance, intestinal mucosal structural damage and inflammation in recipient mice. However, Pb did not exacerbate the metabolic toxicity in HFD mice under depleted gut microbiota.

CONCLUSION

The findings of the present study suggest that Pb induces impairment of glucose metabolism in HFD mice by perturbing the gut microbiota. Our study offers new perspectives on the mechanisms of metabolic toxicity of heavy metals and demonstrates that the gut microbiota may be a target of action for heavy metal exposure. © 2023 Society of Chemical Industry.

Fecal Microbiota Transplantation: A Prospective Treatment for Type 2 Diabetes Mellitus

Purpose of Review

The aim of this review is to summarize the role of gastrointestinal microbiome (GM) in the development of type 2 diabetes mellitus (T2DM). Besides, we discuss the feasibility of applying FMT in the treatment of T2DM and propose a series of processes to refine the use of FMT in the treatment of T2DM.

Recent Findings

T2DM is a metabolic disease which is connected with the GM. According to many researches, GM can produce a variety of metabolites such as bile acid, short chain fatty acids, lipopolysaccharides and trimethylamine oxide which play an important role in metabolism. FMT is a method to regulate GM and has been observed to be effective in the treatment of metabolic diseases such as T2DM in some mouse models and people. However, there is still a lack of direct evidence for the use of FMT in the treatment of T2DM, and the process of FMT is not standardized.

Summary

Dysregulation of GM is closely related to the development of T2DM. Promoting the conversion of GM in T2DM patients to normal population through FMT can reduce insulin resistance and lower their blood glucose level, which is an optional treatment for T2DM patients in the future. At present, the feasibility and limitations of applying FMT to the treatment of T2DM need to be further studied.

Gut microbiota-derived LCA mediates the protective effect of PEDV infection in piglets

BACKGROUND

The gut microbiota is a critical factor in the regulation of host health, but the relationship between the differential resistance of hosts to pathogens and the interaction of gut microbes is not yet clear. Herein, we investigated the potential correlation between the gut microbiota of piglets and their disease resistance using single-cell transcriptomics, 16S amplicon sequencing, metagenomics, and untargeted metabolomics.

RESULTS

Porcine epidemic diarrhea virus (PEDV) infection leads to significant changes in the gut microbiota of piglets. Notably, Landrace pigs lose their resistance quickly after being infected with PEDV, but transplanting the fecal microbiota of Min pigs to Landrace pigs alleviated the infection status. Macrogenomic and animal protection models identified Lactobacillus reuteri and Lactobacillus amylovorus in the gut microbiota as playing an anti-infective role. Moreover, metabolomic screening of the secondary bile acids' deoxycholic acid (DCA) and lithocholic acid (LCA) correlated significantly with Lactobacillus reuteri and Lactobacillus amylovorus, but only LCA exerted a protective function in the animal model. In addition, LCA supplementation altered the distribution of intestinal T-cell populations and resulted in significantly enriched CD8+ CTLs, and in vivo and in vitro experiments showed that LCA increased SLA-I expression in porcine intestinal epithelial cells via FXR receptors, thereby recruiting CD8+ CTLs to exert antiviral effects.

CONCLUSIONS

Overall, our findings indicate that the diversity of gut microbiota influences the development of the disease, and manipulating Lactobacillus reuteri and Lactobacillus amylovorus, as well as LCA, represents a promising strategy to improve PEDV infection in piglets. Video Abstract.

Integrated 16s RNA sequencing and network pharmacology to explore the effects of polyphenol-rich raspberry leaf extract on weight control

Introduction

Obesity is recognized as a chronic low-grade inflammation associated with intestinal flora imbalance, leading to dyslipidemia and inflammation. Modern research has found that polyphenols have anti-obesity effects. However, the mechanism of action of raspberry leaf extract (RLE) with high polyphenols in regulating obesity is still unknown. This study investigated the improvement effect of supplementing RLE on high-fat diet (HFD) induced obesity in mice.

Methods

RLE was used to intervene in HFD induced C57BL/6J male mice during prevention stage (1-16 weeks) and treatment stage (17-20 weeks). Their weight changes and obesity-related biochemical indicators were measured. The changes in intestinal flora were analyzed using 16S rRNA sequencing, and finally the targets and pathways of the 7 typical polyphenols (quercetin-3-O-glucuronide, ellagic acid, kaempferol-3-O-rutinoside, chlorogenic acid, brevifolin carboxylic acid, quercetin-3-O-rutinoside, and quercetin) of RLE in the regulation of obesity were predicted by network pharmacology approach.

Results and discussion

The results showed that RLE effectively prevented and treated weight gain in obese mice induced by HFD, alleviated adipocyte hypertrophy, reduced Interleukin-6 and Tumor Necrosis Factor Alpha levels, and improved intestinal flora, especially Muriaculaceae, Alistipes and Alloprevotella, and decreased the Firmicutes/Bacteroidota ratio. Network pharmacology analysis selected 60 common targets for 7 RLE polyphenols and obesity. Combined with protein-protein interaction network, enrichment analysis and experimental results, TNF, IL-6, AKT1, and PPAR were predicted as potential key targets for RLE polyphenols.

Conclusion

The potential mechanism by which polyphenol-rich RLE regulates obesity may be attributed to the specific polyphenols of RLE and their synergistic effects, therefore RLE has a great anti-obesity potential and may be used as a means to alleviate obesity and related diseases.

Application of Dominant Gut Microbiota Promises to Replace Fecal Microbiota Transplantation as a New Treatment for Alzheimer's Disease

Several studies have confirmed that the pathophysiological progression of Alzheimer's disease (AD) is closely related to changes in the intestinal microbiota; thus, modifying the intestinal microbiota has emerged as a new way to treat AD. Effective interventions for gut microbiota include the application of probiotics and other measures such as fecal microbiota transplantation (FMT). However, the application of probiotics ignores that the intestine is a complete microecosystem with competition among microorganisms. FMT also has issues when applied to patient treatment. In a previous study, we found that eight species of bacteria that are isolated with high frequency in the normal intestinal microbiota (i.e., intestinal dominant microbiota) have biological activities consistent with the effects of FMT. In this article, we confirmed that the treatment of intestinal dominant microbiota significantly restored intestinal microbiota abundance and composition to normal levels in APP/PS1 mice; downregulated brain tissue pro-inflammatory cytokines (IL-1β and IL-6) and amyloid precursor protein (APP) and β-site APP cleavage enzyme 1 (BACE1) expression levels; and reduced the area of Aβ plaque deposition in the brain hippocampus. Our study provides a new therapeutic concept for the treatment of AD, adjusting the intestinal microecological balance through dominant intestinal microbiota may be an alternative to FMT.

The Role of Gut Microbiota in Gestational Diabetes Mellitus Affecting Intergenerational Glucose Metabolism: Possible Mechanisms and Interventions

The incidence of type 2 diabetes is increasing every year and has become a serious public health problem. In addition to genetic factors, environmental factors in early life development are risk factors for diabetes. There is growing evidence that the gut microbiota plays an important role in glucose metabolism, and the gut microbiota of pregnant women with gestational diabetes mellitus (GDM) differs significantly from that of healthy pregnant women. This article reviews the role of maternal gut microbiota in offspring glucose metabolism. To explore the potential mechanisms by which the gut microbiota affects glucose metabolism in offspring, we summarize clinical studies and experimental animal models that support the hypothesis that the gut microbiota affects glucose metabolism in offspring from dams with GDM and discuss interventions that could improve glucose metabolism in offspring. Given that adverse pregnancy outcomes severely impact the quality of survival, reversing the deleterious effects of abnormal glucose metabolism in offspring through early intervention is important for both mothers and their offspring.

Targeting microbiota to alleviate the harm caused by sleep deprivation

Sleep deprivation has become a common health hazard, affecting 37-58% of the population and promoting the occurrence and development of many diseases. To date, effective treatment strategies are still elusive. Accumulating evidence indicates that modulating the intestinal microbiota harbors significant potential for alleviating the deleterious impacts of sleep deprivation. This paper first reviews the effects of sleep deprivation on gastrointestinal diseases, metabolic diseases, and neuropsychiatric diseases, discussing its specific mechanisms of influence. We then focus on summarizing existing interventions, including probiotics, melatonin, prebiotics, diet, and fecal microbiota transplantation (FMT). Finally, we have discussed the advantages and limitations of each strategy. Compared with other strategies, probiotics showed a high potential in alleviating sleep deprivation-related hazards due to their reduced risk and high security. We suggest that future research should focus on the specific mechanisms by which probiotics mitigate the harms of sleep deprivation, such insights may unveil novel pathways for treating diseases exacerbated by insufficient sleep.

The role of the symbiotic microecosystem in cancer: gut microbiota, metabolome, and host immunome

The gut microbiota is not just a simple nutritional symbiosis that parasitizes the host; it is a complex and dynamic ecosystem that coevolves actively with the host and is involved in a variety of biological activities such as circadian rhythm regulation, energy metabolism, and immune response. The development of the immune system and immunological functions are significantly influenced by the interaction between the host and the microbiota. The interactions between gut microbiota and cancer are of a complex nature. The critical role that the gut microbiota plays in tumor occurrence, progression, and treatment is not clear despite the already done research. The development of precision medicine and cancer immunotherapy further emphasizes the importance and significance of the question of how the microbiota takes part in cancer development, progression, and treatment. This review summarizes recent literature on the relationship between the gut microbiome and cancer immunology. The findings suggest the existence of a "symbiotic microecosystem" formed by gut microbiota, metabolome, and host immunome that is fundamental for the pathogenesis analysis and the development of therapeutic strategies for cancer.

Cordyceps cicadae polysaccharides alleviate hyperglycemia by regulating gut microbiota and its mmetabolites in high-fat diet/streptozocin-induced diabetic mice

Introduction

The polysaccharides found in Cordyceps cicadae (C. cicadae) have received increasing academic attention owing to their wide variety of therapeutic activities.

Methods

This study evaluated the hypoglycemic, antioxidant, and anti-inflammatory effects of polysaccharides from C. cicadae (CH-P). In addition, 16s rDNA sequencing and untargeted metabolomics analysis by liquid chromatography-mass spectrometry (LC-MS) were used to estimate the changes and regulatory relationships between gut microbiota and its metabolites. The fecal microbiota transplantation (FMT) was used to verify the therapeutic effects of microbial remodeling.

Results

The results showed that CH-P treatment displayed hypoglycemic, antioxidant, and anti-inflammatory effects and alleviated tissue damage induced by diabetes. The CH-P treatment significantly reduced the Firmicutes/Bacteroidetes ratio and increased the abundance of Bacteroides, Odoribacter, Alloprevotella, Parabacteroides, Mucispirillum, and significantly decreased the abundance of Helicobacter and Lactobacillus compared to the diabetic group. The alterations in the metabolic pathways were mostly related to amino acid biosynthesis and metabolic pathways (particularly those involving tryptophan) according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Correlation analysis showed that Bacteroides, Odoribacter, Alloprevotella, Parabacteroides, and Mucispirillum were positively correlated with indole and its derivatives, such as 5-hydroxyindole-3-acetic acid. Indole intervention significantly improved hyperglycemic symptoms and insulin sensitivity, and increased the secretion of glucagon-like peptide-1 (GLP-1) in diabetic mice. FMT reduced blood glucose levels, improved glucose tolerance, and increased insulin sensitivity in diabetic mice. However, FMT did not significantly improve GLP-1 levels.

Discussion

This indicates that C. cicadae polysaccharides alleviate hyperglycemia by regulating the production of metabolites other than indole and its derivatives by gut microbiota. This study provides an important reference for the development of novel natural products.

Fecal Microbiota Transplantation Revealed a Pain-related Gut Microbiota Community in Ovariectomized Mice

Higher sensitivity to pain is a common clinical symptom in postmenopausal females. The gut microbiota (GM) has recently been identified as participating in various pathophysiological processes and may change during menopause and contribute to multiple postmenopausal symptoms. Here, we investigated the possible correlation between GM alteration and allodynia in ovariectomized (OVX) mice. Results showed that OVX mice exhibited allodynia from 7 weeks after surgery compared with sham-operated (SHAM) mice by comparing pain-related behaviors. Fecal microbiota transplantation (FMT) from OVX mice induced allodynia in normal mice while FMT from SHAM mice alleviated allodynia in OVX mice. Microbiome 16S rRNA sequencing and linear discriminant analysis revealed alteration of the GM after OVX. Furthermore, Spearman's correlation analysis showed associations between pain-related behaviors and genera, and further verification identified the possible pain-related genera complex. Our findings provide new insights into the underlying mechanisms of postmenopausal allodynia, and suggest pain-related microbiota community as a promising therapeutic target. PERSPECTIVE: This article provided the evidence of gut microbiota playing essential roles in postmenopausal allodynia. This work intended to offer a guidance for further mechanism investigation into gut-brain axis and probiotics screening for postmenopausal chronic pain.

Association between Intestinal Microecological Changes and Atherothrombosis

Atherosclerosis (AS) is a chronic inflammatory disease of large- and medium-sized arteries that causes ischemic heart disease, strokes, and peripheral vascular disease, collectively called cardiovascular disease (CVD), and is the leading cause of CVD resulting in a high rate of mortality in the population. AS is pathological by plaque development, which is caused by lipid infiltration in the vessel wall, endothelial dysfunction, and chronic low-grade inflammation. Recently, more and more scholars have paid attention to the importance of intestinal microecological disorders in the occurrence and development of AS. Intestinal G-bacterial cell wall lipopolysaccharide (LPS) and bacterial metabolites, such as oxidized trimethylamine (TMAO) and short-chain fatty acids (SCFAs), are involved in the development of AS by affecting the inflammatory response, lipid metabolism, and blood pressure regulation of the body. Additionally, intestinal microecology promotes the progression of AS by interfering with the normal bile acid metabolism of the body. In this review, we summarize the research on the correlation between maintaining a dynamic balance of intestinal microecology and AS, which may be potentially helpful for the treatment of AS.

Obesity Measured via Body Mass Index May Be Associated with Increased Incidence but Not Worse Outcomes of Immune-Mediated Diarrhea and Colitis

Obesity defined by high body mass index (BMI) has traditionally been associated with gastrointestinal inflammatory processes but has recently been correlated with better survival in patients receiving immune checkpoint inhibitors (ICI). We sought to investigate the association between BMI and immune-mediated diarrhea and colitis (IMDC) outcomes and whether BMI reflects body fat content on abdominal imaging. This retrospective, single-center study included cancer patients with ICI exposure who developed IMDC and had BMI and abdominal computed tomography (CT) obtained within 30 days before initiating ICI from April 2011 to December 2019. BMI was categorized as <25, ≥25 but <30, and ≥30. Visceral fat area (VFA), subcutaneous fat area (SFA), total fat area (TFA: VFA+SFA), and visceral to subcutaneous fat (V/S) ratio were obtained from CT at the umbilical level. Our sample comprised 202 patients; 127 patients (62.9%) received CTLA-4 monotherapy or a combination, and 75 (37.1%) received PD-1/PD-L1 monotherapy. Higher BMIs ≥ 30 were associated with a higher incidence of IMDC than BMIs ≤ 25 (11.4% vs. 7.9%, respectively; p = 0.029). Higher grades of colitis (grade 3-4) correlated with lower BMI (p = 0.03). BMI level was not associated with other IMDC characteristics or did not influence overall survival (p = 0.83). BMI is strongly correlated with VFA, SFA, and TFA (p < 0.0001). Higher BMI at ICI initiation was linked to a higher incidence of IMDC but did not appear to affect outcomes. BMI strongly correlated with body fat parameters measured by abdominal imaging, suggesting its reliability as an obesity index.

Gut Microbiota Dysbiosis Ameliorates in LNK-Deficient Mouse Models with Obesity-Induced Insulin Resistance Improvement

PURPOSE

To investigate the potential role of gut microbiota in obesity-induced insulin resistance (IR).

METHODS

Four-week-old male C57BL/6 wild-type mice (n = 6) and whole-body SH2 domain-containing adaptor protein (LNK)-deficient in C57BL/6 genetic backgrounds mice (n = 7) were fed with a high-fat diet (HFD, 60% calories from fat) for 16 weeks. The gut microbiota of 13 mice feces samples was analyzed by using a 16 s rRNA sequencing analysis.

RESULTS

The structure and composition of the gut microbiota community of WT mice were significantly different from those in the LNK-/- group. The abundance of the lipopolysaccharide (LPS)-producing genus Proteobacteria was increased in WT mice, while some short-chain fatty acid (SCFA)-producing genera in WT groups were significantly lower than in LNK-/- groups (p < 0.05).

CONCLUSIONS

The structure and composition of the intestinal microbiota community of obese WT mice were significantly different from those in the LNK-/- group. The abnormality of the gut microbial structure and composition might interfere with glucolipid metabolism and exacerbate obesity-induced IR by increasing LPS-producing genera while reducing SCFA-producing probiotics.

A Single Strain of Lactobacillus (CGMCC 21661) Exhibits Stable Glucose- and Lipid-Lowering Effects by Regulating Gut Microbiota

Type 2 diabetes (T2D) is usually accompanied by obesity and nonalcoholic fatty-liver-related insulin resistance. The link between T2D and dysbiosis has been receiving increasing attention. Probiotics can improve insulin sensitivity by regulating imbalances in microbiota, but efficacy varies based on the probiotic used. This study screened the main strain in the feces of healthy adult mice and found it to be a new Lactobacillus (abbreviated as Lb., named as CGMCC No. 21661) after genetic testing. We designed the most common Bifidobacterium longum subsp. longum (CGMCC1.2186, abbreviated as B. longum. subsp.), fecal microbiota transplantation (FMT), and Lb. CGMCC No. 21661 protocols to explore the best way for modulating dysbiosis to improve T2D. After 6 weeks of gavage in T2D mice, it was found that all three protocols had a therapeutic alleviating effect. Among them, compared with the B. longum. subsp. and FMT, the Lb. CGMCC No. 21661 showed a 1- to 2-fold decrease in blood glucose (11.84 ± 1.29 mmol/L, p < 0.05), the lowest HOMA-IR (p < 0.05), a 1 fold increase in serum glucagon-like peptide-1 (5.84 ± 1.1 pmol/L, p < 0.05), and lowest blood lipids (total cholesterol, 2.21 ± 0.68 mmol/L, p < 0.01; triglycerides, 0.4 ± 0.15 mmol/L, p < 0.01; Low-density lipoprotein cholesterol, 0.53 ± 0.16 mmol/L, p < 0.01). In addition, tissue staining in the Lb. CGMCC No. 21661 showed a 2- to 3-fold reduction in T2D-induced fatty liver (p < 0.0001), a 1- to 2-fold decrease in pancreatic apoptotic cells (p < 0.05), and a significant increase in colonic mucus layer thickness (p < 0.05) compared with the B. longum. subsp. and FMT. The glucose and lipid lowering effects of this Lb. CGMCC No. 21661 indicate that it may provide new ideas for the treatment of diabetes.

Immune mechanism of gut microbiota and its metabolites in the occurrence and development of cardiovascular diseases

The risk of cardiovascular disease (CVD) is associated with unusual changes in the human gut microbiota, most commonly coronary atherosclerotic heart disease, hypertension, and heart failure. Immune mechanisms maintain a dynamic balance between the gut microbiota and the host immune system. When one side changes and the balance is disrupted, different degrees of damage are inflicted on the host and a diseased state gradually develops over time. This review summarizes the immune mechanism of the gut microbiota and its metabolites in the occurrence of common CVDs, discusses the relationship between gut-heart axis dysfunction and the progression of CVD, and lists the currently effective methods of regulating the gut microbiota for the treatment of CVDs.

Fecal microbiota transplantation in non-communicable diseases: Recent advances and protocols

Fecal microbiota transplant (FMT) is a therapeutic method that aims to restore normal gut microbial composition in recipients. Currently, FMT is approved in the USA to treat recurrent and refractory Clostridioides difficile infection and has been shown to have great efficacy. As such, significant research has been directed toward understanding the potential role of FMT in other conditions associated with gut microbiota dysbiosis such as obesity, type 2 diabetes mellitus, metabolic syndrome, neuropsychiatric disorders, inflammatory bowel disease, irritable bowel syndrome, decompensated cirrhosis, cancers and graft-versus-host disease. This review examines current updates and efficacy of FMT in treating conditions other than Clostridioides difficile infection. Further, protocols for administration of FMT are also discussed including storage of fecal samples in stool banks, inclusion/exclusion criteria for donors, fecal sample preparation and methods of treatment administration. Overall, understanding the mechanisms by which FMT can manipulate gut microbiota to provide therapeutic benefit as well as identifying potential adverse effects is an important step in clarifying its long-term safety and efficacy in treating multiple conditions in the future.

Possibilities of Autologous Fecal Microbiota Transplantation in patients with obesity and diabetes mellitus

Obesity and type 2 diabetes mellitus (T2DM) are major problems for public health all over the world. According to retrospective research, the prevalence of obesity has doubled in more than 70 countries since 1980, as well as the prevalence of obesity complications (atherosclerotic cardiovascular diseases, nonalcoholic fatty liver disease and their complications. There are many drug therapies for T2DM, but it is difficult to achieve a stable, clinically relevant effect on a long-term basis. The fact that a patient has both conditions makes it difficult to optimize carbohydrate metabolism and to achieve normal body weight. Many antidiabetic drugs cause weight again, which, in turn, contributes to the growth of insulin resistance (IR) and requires further intensification of therapy.

In the last few years, there is a growing evidence of the relationship between the gut microbiota (GM), obesity and T2DM. There has been a steady growth of interest in such medical technology as fecal microbiota transplantation (FMT) in the world. Since there is data on the association of the gut microbiota (GM) with the development of IR and T2DM, the possibility of FMT can potentially be one of the new methods of treatment. This review presents the current state of the problem and discusses the possibility of modifying GM as a therapeutic strategy in obesity and T2DM with an accent on autologous fecal microbiota transplantation.

Therapeutic Effects of Gut Microbiota on Metabolic Syndrome: A Patent Review

BACKGROUND

The balanced composition of the gut microbiota is essential for human health. The dysbiotic condition may develop various complex diseases. A metabolic syndrome is a group of biochemical and physiological abnormalities that can increase the risk of cardiovascular diseases, diabetes, and inflammatory diseases. It has become a serious concern worldwide because there is no acceptable medication to overcome this problem.

OBJECTIVE

This review aims to evaluate the relationship between gut microbiota and metabolic syndrome. The balance of gut microbiota relates to human health as well as diseases. Patents related to significant findings on probiotics, prebiotics, synbiotics, and fecal microbiota transplantation signify the importance of the proposed theme and provide promising therapeutic strategies to modulate the dysbiotic condition and reoccurrence of beneficial microbial species during metabolic syndromes. Screening of patents-related databases can be worth full to track new technology. Therefore, some selected recent patents related to gut microbiota and associated therapies have been discussed in the present manuscript.

CONCLUSION

Under the existing situation, the role of gastrointestinal microbiota as a therapeutic agent is becoming more utilized for treating human health issues and various metabolic syndromes including obesity, diabetes, and cardiovascular diseases. Understanding gut dysbiosis and associated complex interactions between microbes and hosts would be effective for designing future therapeutic interventions for metabolic syndrome. Our detailed patent analysis reflects that gut dysbiosis has a prominent role in metabolic syndromes and dietary therapeutic strategies can improve health by modulating the human microbiota, their metabolites ad stability.

Bibliometric and visual analysis of fecal microbiota transplantation research from 2012 to 2021

BACKGROUND

Fecal microbiota transplantation (FMT) is an emerging therapy for diseases associated with intestinal flora imbalance that has attracted increasing attention in recent years. This study aims to provide an overview of research trends in the field, and act as a reference point for future scientific research by analyzing the state of current research, identifying hotspots, and potential frontiers of FMT.

METHODS

Articles relating to FMT that were published between the years 2012 and 2021 were retrieved from the Web of Science Core Collection. Bibliometric analysis was performed using Microsoft Excel and CiteSpace.

RESULTS

A total of 2,403 English language articles relating to FMT research were published over the last ten years. Most of this research was carried out in the United States of America, with Harvard Medical school being the most productive institution. Much of the research was published in the PLoS One journal. Alexander Khoruts was identified as a prominent, productive researcher in the field. Keyword analysis revealed that research hot spots included gut microbiota, Clostridium difficile infection (CDI), and diseases. Burst detection indicated that future research frontiers include clinical practice guidelines and strategies.

CONCLUSION

Our analysis explored hot spots and emerging trends in the FMT field. Indications for use of FMT extended from digestive system diseases to other systemic diseases. Additionally, areas such as risk assessment and control, along with application methods were also a focus of current research. Moreover, research relating to optimization of clinical practice has excellent prospects.

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.

Regulation of viable/inactivated/lysed probiotic Lactobacillus plantarum H6 on intestinal microbiota and metabolites in hypercholesterolemic mice

Evidence suggests that probiotic interventions reduce non-communicable diseases (NCDs) risk. However, its therapeutic effect and mechanism are still unclear. To evaluate the hypocholesterolemic effect of Lactobacillus plantarum H6 (L.p H6), a new commercial patent strain capable of preventing hypercholesterolemia, and its mechanism in depth, three states of the strain were prepared, namely, viable (vH6), heat-inactivated (iH6), and ultrasonically-lysed (uH6) bacteria cells. The results showed that v/i/uH6 cells could lower serum and liver blood lipid levels, alleviate liver damage and improve glucose tolerance test (GTT) and insulin tolerance test (ITT) indexes. v/i/uH6 cells improved the gut microbial composition and significantly reduced the Firmicutes to Bacteroidetes ratio (F/B ratio) in feces. In particular, Muribaculaceae may be a potential biomarker for effective cholesterol reduction. Also, the recovery of these biochemical indices and gut microbiome was found following fecal microbiota transplantation (FMT) using stool from vH6 treated mice. The v/i/uH6 cells increased the intestinal flora metabolism of vitamins-cofactors, as well as amino acids, while decreasing the relative content of primary bile acids. The Pearson correlation analysis showed that norank_f__Muribaculaceae and Lactobacillus had a negative correlation with blood lipid levels. Overall, v/i/uH6 cells were effective in improving hypercholesterolemia in mice, and this effect was attributed partly to the regulation of intestinal microbiota and metabolites related to lipid metabolism. Our findings provided a theoretical basis for the industrial development of probiotics and postbiotics and the treatment of cholesterol diseases.

Current Trends and Challenges of Fecal Microbiota Transplantation-An Easy Method That Works for All?

The gut microbiota refers to bacteria lodges in the gastrointestinal tract (GIT) that interact through various complex mechanisms. The disturbance of this ecosystem has been correlated with several diseases, such as neurologic, respiratory, cardiovascular, and metabolic diseases and cancer. Therefore, the modulation of the gut microbiota has emerged as a potential therapeutic tool; of the various forms of gut microbiota modulation, fecal microbiota transplantation (FMT) is the most approached. This recent technique involves introducing fecal material from a healthy donor into the patient's gastrointestinal tract, aiming to restore the gut microbiota and lead to the resolution of symptoms. This procedure implies a careful donor choice, fine collection and handling of fecal material, and a balanced preparation of the recipient and consequent administration of the prepared content. Although FMT is considered a biological therapy with promising effects, side effects such as diarrhea and abdominal pain have also been claimed, making this a significant challenge in the application of FMT. Bearing this in mind, the present review aims to summarize the recent advances in understanding FMT mechanisms, their impact across different pathological conditions, and the associated side effects, emphasizing the most recent published data.

Challenges and costs of donor screening for fecal microbiota transplantations

BACKGROUND

The increasing interest to perform and investigate the efficacy of fecal microbiota transplantation (FMT) has generated an urge for feasible donor screening. We report our experience with stool donor recruitment, screening, follow-up, and associated costs in the context of clinical FMT trials.

METHODS

Potential stool donors, aged between 18-65 years, underwent a stepwise screening process starting with an extensive questionnaire followed by feces and blood investigations. When eligible, donors were rescreened for MDROs and SARS-CoV-2 every 60-days, and full rescreening every 4-6 months. The costs to find and retain a stool donor were calculated.

RESULTS

From January 2018 to August 2021, 393 potential donors underwent prescreening, of which 202 (51.4%) did not proceed primarily due to loss to follow-up, medication use, or logistic reasons (e.g. COVID-19 measures). 191 potential donors filled in the questionnaire, of which 43 (22.5%) were excluded. The remaining 148 candidates underwent parasitology screening: 91 (61.5%) were excluded, mostly due to Dientamoeba fragilis and/or high amounts of Blastocystis spp. After additional feces investigations 18/57 (31.6%) potential donors were excluded (mainly for presence of Helicobacter Pylori and ESBL-producing organisms). One donor failed serum testing. Overall, 38 out of 393 (10%) potential donors were enrolled. The median participation time of active stool donors was 13 months. To recruit 38 stool donors, €64.112 was spent.

CONCLUSION

Recruitment of stool donors for FMT is challenging. In our Dutch cohort, failed eligibility of potential donors was often caused by the presence of the protozoa Dientamoeba fragilis and Blastocystis spp.. The exclusion of potential donors that carry these protozoa, especially Blastocystis spp., is questionable and deserves reconsideration. High-quality donor screening is associated with substantial costs.

Precise strategies for selecting probiotic bacteria in treatment of intestinal bacterial dysfunctional diseases

Abundant microbiota resides in the organs of the body, which utilize the nutrition and form a reciprocal relationship with the host. The composition of these microbiota changes under different pathological conditions, particularly in response to stress and digestive diseases, making the microbial composition and health of the hosts body interdependent. Probiotics are living microorganisms that have demonstrated beneficial effects on physical health and as such are used as supplements to ameliorate symptoms of various digestive diseases by optimizing microbial composition of the gut and restore digestive balance. However, the supplementary effect does not achieve the expected result. Therefore, a targeted screening strategy on probiotic bacteria is crucial, owing to the presence of several bacterial strains. Core bacteria work effectively in maintaining microbiological homeostasis and stabilization in the gastrointestinal tract. Some of the core bacteria can be inherited and acquired from maternal pregnancy and delivery; others can be acquired from contact with the mother, feces, and the environment. Knowing the genera and functions of the core bacteria could be vital in the isolation and selection of probiotic bacteria for supplementation. In addition, other supporting strains of probiotic bacteria are also needed. A comprehensive strategy for mining both core and supporting bacteria before its clinical use is needed. Using metagenomics or other methods of estimation to discern the typically differentiated strains of bacteria is another important strategy to treat dysbiosis. Hence, these two factors are significant to carry out targeted isolation and selection of the functional strains to compose the resulting probiotic preparation for application in both research and clinical use. In conclusion, precise probiotic supplementation, by screening abundant strains of bacteria and isolating specific probiotic strains, could rapidly establish the core microbiota needed to confer resilience, particularly in bacterial dysfunctional diseases. This approach can help identify distinct bacteria which can be used to improve supplementation therapies.

“Growth-Promoting Effect” of Antibiotic Use Could Explain the Global Obesity Pandemic: A European Survey

Clinical observations indicated a higher rate of obesity among children who received antibiotics at early ages. Experimental studies supported the role of the modified gut microbiome in the development of obesity as well. For identifying antibiotic classes that might promote or inhibit obesity-related dysbiosis, a database of the average yearly antibiotic consumption (2008–2018) has been developed using the European Center for Disease Prevention and Control (ECDC) yearly reports of antibiotic consumption in the community for the major antibiotic classes in 30 European countries, which were compared to the childhood and adult obesity prevalence featured in the Obesity Atlas. Pearson’s chi-square test was applied to estimate positive/negative correlations between antibiotic consumption and obesity. One-way ANOVA has been applied to test the differences in antibiotic consumption between groups, and logistic regression analysis was performed to determine the odds ratios (OR) of antibiotic consumption for obesity. Strong, positive associations were estimated between childhood obesity and the total consumption of systemic antibiotics, broad-spectrum, beta-lactamase-resistant penicillin, cephalosporin, and quinolone, and a negative correlation was found with the consumption of tetracycline, broad-spectrum, beta-lactamase-sensitive penicillin, and narrow-spectrum, beta-lactamase-sensitive penicillin. Our observation indicated that the “growth-promoting effect” of the consumption of certain antibiotic classes might be identified as a possible etiology in the development of obesity and might be the explanation for the obesity “pandemic”.

Applications of human organoids in the personalized treatment for digestive diseases

Digestive system diseases arise primarily through the interplay of genetic and environmental influences; there is an urgent need in elucidating the pathogenic mechanisms of these diseases and deploy personalized treatments. Traditional and long-established model systems rarely reproduce either tissue complexity or human physiology faithfully; these shortcomings underscore the need for better models. Organoids represent a promising research model, helping us gain a more profound understanding of the digestive organs; this model can also be used to provide patients with precise and individualized treatment and to build rapid in vitro test models for drug screening or gene/cell therapy, linking basic research with clinical treatment. Over the past few decades, the use of organoids has led to an advanced understanding of the composition of each digestive organ and has facilitated disease modeling, chemotherapy dose prediction, CRISPR-Cas9 genetic intervention, high-throughput drug screening, and identification of SARS-CoV-2 targets, pathogenic infection. However, the existing organoids of the digestive system mainly include the epithelial system. In order to reveal the pathogenic mechanism of digestive diseases, it is necessary to establish a completer and more physiological organoid model. Combining organoids and advanced techniques to test individualized treatments of different formulations is a promising approach that requires further exploration. This review highlights the advancements in the field of organoid technology from the perspectives of disease modeling and personalized therapy.

Washed microbiota transplantation improves patients with high blood glucose in South China

Background and Aims

Although fecal microbiota transplantation (FMT) from healthy donors has been shown to have hypoglycemic effects in animal models of diabetes, its clinical impact in patients with abnormal blood glucose metabolism is unclear, especially in southern Chinese populations. The aim of this study was to investigate the feasibility and efficacy of washed microbiota transplantation (WMT) in the treatment of abnormal blood glucose metabolism in a population in southern China.

Methods

The clinical data of patients with different indications who received 1-3 treatments of WMT were retrospectively collected. The changes of blood glucose, blood lipids, blood pressure, liver function and blood routine before and after WMT were compared, such as fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), systolic blood pressure (SBP), white blood cells (WBC), lymphocytes (LY) and platelets (PLT), etc.

Results

A total of 195 patients were included in the First Affiliated Hospital of Guangdong Pharmaceutical University, including 20 patients with high blood glucose and 175 patients with normal blood glucose. WMT has a significant effect in reducing short term blood glucose level (FBG) in patients with high blood glucose (p < 0.05). The fasting blood glucose (FBG) of 72.22% of patients with high blood glucose decreased to normal in a short term (about 1 month) (p < 0.001); In the medium term (about 2 months), there was a significant hypolipidemic (TG) (p = 0.043) effect, long term (about 6 months) significant blood pressure lowering (SBP, p = 0.048) effect. Overall, WMT significantly reduced the risk of high risk classes of Atherosclerotic Cardiovascular Disease (ASCVD) in the short term (p = 0.029) and medium term (p = 0.050).

Conclusion

WMT can significantly improve blood glucose in patients with high blood glucose, and there is no long-term elevated risk of blood glucose and ASCVD. FBG levels were significantly reduced in both the short and medium term in patients with high blood glucose treated with WMT. Therefore, the regulation of gut microbiota by WMT may provide a new clinical approach for the treatment of abnormal blood glucose metabolism.

Global research trends and hotspots of fecal microbiota transplantation: A bibliometric and visualization study

Introduction

Fecal microbiota transplantation (FMT) has gained considerable attention in a variety of clinical research areas, and an increasing number of articles are being published. It is very critical to reveal the global status, future research trends, and hotspots in the FMT research and application.

Methods

We searched the Web of Science Core Collection up to May 10, 2022, and only articles and review articles about FMT were included finally. CiteSpace 5.8.R3, VOSviewer 1.6.18, Scimago Graphica and Microsoft Office Excel 2019 were used for data analysis and visualization. The results included publication characteristics, Co-authorships analysis, Co-cited analysis, Co-occurrence analysis, and burst analysis.

Results

Eleven thousand nine hundred seventy-two records were used for the analysis and visualization finally, these records were published between 1980 and 2022, and the publication about FMT is increasing year by year. Co-authorship analysis shown that the USA played a key role in this field. After data analysis and visualization, a total of 57 hotspots about FMT were produced. We summarized these hotspots and classified them into 7 grades according to the number of evidence sources. The evidence sources included top 25 of Web of Science categories, top 30 most Co-cited references, top 10 clusters of references, top 25 references with the strongest citation bursts, top 25 keywords with the most occurrence frequency, major 15 clusters of keywords, top 25 keywords with the strongest citation bursts, and top 35 disease keywords.

Conclusion

This bibliometric analysis is expected to provide overall perspective for FMT. FMT has gained increasing attention and interest, there are many hotspots in this field, which may help researchers to explore new directions for future research.

“Bacterial Consortium”: A Potential Evolution of Fecal Microbiota Transplantation for the Treatment of Clostridioides difficile Infection

Fecal microbiota transplantation (FMT) consists of infusion of feces from a donor to a recipient patient in order to restore the resident microbial population. FMT has shown to be a valid clinical option for Clostridioides difficile infections (CDI). However, this approach shows several criticalities, such as the recruiting and screening of voluntary donors. Our aim was to evaluate the therapeutic efficacy of a synthetic bacterial suspension defined “Bacterial Consortium” (BC) infused in the colon of CDI patients. The suspension was composed by 13 microbial species isolated by culturomics protocols from healthy donors' feces. The efficacy of the treatment was assessed both clinically and by metagenomics typing. Fecal samples of the recipient patients were collected before and after infusion. DNA samples obtained from feces at different time points (preinfusion, 7, 15, 30, and 90 days after infusion) were analyzed by next-generation sequencing. Before infusion, patient 1 showed an intestinal microbiota dominated by the phylum Bacteroidetes. Seven days after the infusion, Bacteroidetes decreased, followed by an implementation of Firmicutes and Verrucomicrobia. Patient 2, before infusion, showed a strong abundance of Proteobacteria and a significant deficiency of Bacteroidetes and Verrucomicrobia. Seven days after infusion, Proteobacteria strongly decreased, while Bacteroidetes and Verrucomicrobia increased. Metagenomics data revealed an “awakening” by microbial species absent or low concentrated at time T0 and present after the infusion. In conclusion, the infusion of selected bacteria would act as a trigger factor for “bacterial repopulation” representing an innovative treatment in patients with Clostridioides difficile infections.