Gut microbiota and gastrointestinal health: current concepts and future directions

D, Rajendran P, N H, Singh S A. Exploring the potential of probiotics in Alzheimer's disease and gut dysbiosis

Alzheimer's disease is a fatal neurodegenerative disorder that causes memory loss and cognitive decline in older people. There is increasing evidence suggesting that gut microbiota alteration is a cause of Alzheimer's disease pathogenesis. This review explores the link between gut dysbiosis and the development of Alzheimer's disease contributing to neuroinflammation, amyloid β accumulation, and cognitive decline. We examine the recent studies that illustrate the gut-brain axis (GBA) as a bidirectional communication between the gut and brain and how its alteration can influence neurological health. Furthermore, we discuss the potential of probiotic supplementation as a management approach to restore gut microbiota balance, and ultimately improve cognitive function in AD patients. Based on current research findings, this review aims to provide insights into the promising role of probiotics in Alzheimer's disease management and the need for further investigation into microbiota-targeted interventions.

Probiotics in piglet: from gut health to pathogen defense mechanisms

Various problems and obstacles are encountered during pig farming, especially the weaning phase when switching from liquid to solid feed. Infection by pathogenic bacteria causes damage to the intestinal barrier function of piglets, disrupts the balance of the intestinal microbiota, and destroys the chemical, mechanical, and immune barriers of the intestinal tract, which is one of the main causes of gut inflammation or gut diseases in piglets. The traditional method is to add antibiotics to piglet diets to prevent bacterial infections. However, long-term overuse of antibiotics leads to bacterial resistance and residues in animal products, threatening human health and causing gut microbiota dysbiosis. In this context, finding alternatives to antibiotics to maintain pre- and post-weaning gut health in piglets and prevent pathogenic bacterial infections becomes a real emergency. The utilization of probiotics in piglet nutrition has emerged as a pivotal strategy to promote gut health and defend against pathogenic infections, offering a sustainable alternative to traditional antibiotic usage. This review introduces recent findings that underscore the multifaceted roles of probiotics in enhancing piglet welfare, from fortifying the gut barrier to mitigating the impacts of common bacterial pathogens. Meanwhile, this study introduces the functions of probiotics from different perspectives: positive effects of probiotics on piglet gut health, protecting piglets against pathogen infection, and the mechanisms of probiotics in preventing pathogenic bacteria.

Oral delivery of sodium alginate/chitosan bilayer microgels loaded with Lactobacillus rhamnosus GG for targeted therapy of ulcerative colitis

Probiotics regulate intestinal flora balance and enhance the intestinal barrier, which is useful in preventing and treating colitis. However, they have strict storage requirements. In addition, they degrade in a strongly acidic environment, resulting in a significant decrease in their activity when used as microbial agents. Lactobacillus rhamnosus GG (LGG) was loaded into acid-resistant and colon-targeting double-layer microgels. The inner layer consists of guar gum (GG) and low methoxyl pectin (LMP), which can achieve retention and degradation in the colon. To achieve colon localization, the outer layer was composed of chitosan (CS) and sodium alginate (SA). The formulation demonstrated favorable bio-responses across various pH conditions in vitro and sustained release of LGG in the colon lesions. Bare LGG survival decreased by 52.2 % in simulated gastric juice (pH 1.2) for 2 h, whereas that of encapsulated LGG decreased by 18.5 %. In the DSS-induced inflammatory model, LGG-loaded microgel significantly alleviated UC symptoms in mice and reduced inflammatory factor levels in the colon. Encapsulation of LGG improved its stability in acidic conditions, thus increasing its content at the colon lesions and reducing pathogenic bacteria. These findings provide an experimental basis and a technical reference for developing and applying probiotic microgel preparations.

The Efficacy of Probiotics Supplementation on the Quality of Life of Patients with Gastrointestinal Disease: A Systematic Review of Clinical Studies

Patients with gastrointestinal (GI) disorders might benefit from probiotic supplementation to resolve their bowel symptoms and enhance their quality of life (QoL). This systematic review aimed to evaluate the effects of oral probiotic supplementation on improving QoL. Relevant studies were systematically searched in online databases, including PubMed, Scopus, Embase, ProQuest, and Google Scholar up to September 2022 using relevant keywords. Studies that were conducted on GI patients and presented QoL outcomes were included. The Revised Cochrane Risk of Bias 2 tool and the Risk Of Bias In Non-randomized Studies of Intervention tool were used to assess the risk of bias. Of the 4,555 results found in the systematic search of databases, only 36 studies were eligible for evaluation. According to this systematic review, 24 studies reported improvements, whereas 12 studies reported no improvements on QoL in GI patients supplemented with probiotics. We found that probiotics may improve the QoL of patients with GI diseases and related metabolic complications. Therefore, probiotics can be a useful supportive treatment strategy in these patients.

Gut Microbiota in the Progression of Type 2 Diabetes and the Potential Role of Exercise: A Critical Review

Type 2 diabetes (T2D) is the predominant metabolic epidemic posing a major threat to global health. Growing evidence indicates that gut microbiota (GM) may critically influence the progression from normal glucose tolerance, to pre-diabetes, to T2D. On the other hand, regular exercise contributes to the prevention and/or treatment of the disease, and evidence suggests that a possible way regular exercise favorably affects T2D is by altering GM composition toward health-promoting bacteria. However, research regarding this potential effect of exercise-induced changes of GM on T2D and the associated mechanisms through which these effects are accomplished is limited. This review presents current data regarding the association of GM composition and T2D and the possible critical GM differentiation in the progression from normal glucose, to pre-diabetes, to T2D. Additionally, potential mechanisms through which GM may affect T2D are presented. The effect of exercise on GM composition and function on T2D progression is also discussed.

Meta-analysis of gut microbiota biodiversity in patients with polycystic ovary syndrome based on medical images

PCOS is thought to be associated with metabolic disorders, endocrine disorders, and reproductive system problems. By collecting relevant literature and conducting meta-analyses, we integrated data from multiple studies to enhance the reliability of the analysis results. Studies with medical image data were selected to ensure the accuracy and credibility of the studies. A statistical framework was employed to examine the biodiversity indicators associated with the gut microbiota. These findings provide robust support for the notion that PCOS is intricately linked to notable alterations within the gut microbial community. The utilization of a statistical approach and the systematic synthesis of research findings in this meta-analysis contribute to a more comprehensive understanding of the substantial impact of PCOS on the gut microbiota landscape. PCOS patients showed significant changes in the relative abundance of certain bacteria in their gut microbiota. This imbalance will lead to the instability of intestinal microecological environment, and then affect the health of the body.

Dietary fiber supplementation increases Drosophila melanogaster lifespan and gut microbiota diversity

Dietary fiber has been shown to have multiple health benefits, including a positive effect on longevity and the gut microbiota. In the present study, Drosophila melanogaster has been chosen as an in vivo model organism to study the health effects of dietary fiber supplementation (DFS). DFS extended the mean half-life of male and female flies, but the absolute lifespan only increased in females. To reveal the underlying mechanisms, we examined the effect of DFS on gut microbiota diversity and abundance, local gut immunity, and the brain proteome. A significant difference in the gut microbial community was observed between groups with and without fiber supplementation, which reduced the gut pathogenic bacterial load. We also observed an upregulated expression of dual oxidase and a modulated expression of Attacin and Diptericin genes in the gut of older flies, possibly delaying the gut dysbiosis connected to the age-related gut immune dysfunction. Brain proteome analysis showed that DFS led to the modulation of metabolic processes connected to mitochondrial biogenesis, the RhoV-GTPase cycle, organelle biogenesis and maintenance, membrane trafficking and vesicle-mediated transport, possibly orchestrated through a gut-brain axis interaction. Taken together, our study shows that DFS can prolong the half-life and lifespan of flies, possibly by promoting a healthier gut environment and delaying the physiological dysbiosis that characterizes the ageing process. However, the RhoV-GTPase cycle at the brain level may deserve more attention in future studies.

Spatial profiles of the bacterial microbiota throughout the gastrointestinal tract of dairy goats

The gastrointestinal tract (GIT) is stationed by a dynamic and complex microbial community with functions in digestion, metabolism, immunomodulation, and reproduction. However, there is relatively little research on the composition and function of microorganisms in different GIT segments in dairy goats. Herein, 80 chyme samples were taken from ten GIT sites of eight Xinong Saanen dairy goats and then analyzed and identified the microbial composition via 16S rRNA V1-V9 amplicon sequencing. A total of 6669 different operational taxonomic units (OTUs) were clustered, and 187 OTUs were shared by ten GIT segments. We observed 264 species belonging to 23 different phyla scattered across ten GITs, with Firmicutes (52.42%) and Bacteroidetes (22.88%) predominating. The results revealed obvious location differences in the composition, diversity, and function of the GIT microbiota. In LEfSe analysis, unidentified_Lachnospiraceae and unidentified_Succinniclassicum were significantly enriched in the four chambers of stomach, with functions in carbohydrate fermentation to compose short-chain fatty acids. Aeriscardovia, Candidatus_Saccharimonas, and Romboutsia were significantly higher in the foregut, playing an important role in synthesizing enzymes, amino acids, and vitamins and immunomodulation. Akkermansia, Bacteroides, and Alistipes were significantly abundant in the hindgut to degrade polysaccharides and oligosaccharides, etc. From rumen to rectum, α-diversity decreased first and then increased, while β-diversity showed the opposite trend. Metabolism was the major function of the GIT microbiome predicted by PICRUSt2, but with variation in target substrates along the regions. In summary, GIT segments play a decisive role in the composition and functions of microorganisms. KEY POINTS: • The jejunum and ileum were harsh for microorganisms to colonize due to the presence of bile acids, enzymes, faster chyme circulation, etc., exhibiting the lowest α-diversity and the highest β-diversity. • Variability in microbial profiles between the three foregut segments was greater than four chambers of stomach and hindgut, with a higher abundance of Firmicutes dominating than others. • Dairy goats dominated a higher abundance of Kiritimatiellaeota than cows, which was reported to be associated with fatty acid synthesis.

Effects of dietary citrus pulp level on the growth and intestinal health of largemouth bass (Micropterus salmoides)

BACKGROUND

Citrus pulp (CP) is rich in pectin, and studies have shown that pectin possesses antioxidant, anti-inflammatory, and gut microbiota-regulating properties. However, the application of CP in aquafeed is limited. In this study, the effect of dietary inclusion of CP on the intestinal health of largemouth bass (Micropterus salmoides) was investigated. Juveniles of similar size (6.95 ± 0.07 g) were fed isonitrogenous and isoenergetic diets containing different levels of CP (0%, 3%, 6%, 9%, 12%, or 15%) for 58 days.

RESULTS

As the level of CP in the feed for largemouth bass increased, the fish's growth performance and intestinal health initially improved and then declined. Adding low doses of CP (≤9%) to the feed had no significant impact on the growth performance of large-mouth black bass, whereas high doses of CP (>9%) significantly reduced their growth performance. Adding 6%, 9%, or 12% of CP to that feed enhanced the expression of genes related to tight junctions, anti-inflammatory activity, anti-apoptotic activity, and antioxidant activity in the intestines of largemouth bass. It reduced intestinal inflammation and improved intestinal nutrient absorption, intestinal mucosal barrier function, and intestinal antioxidant capacity. Moreover, it improved the α-diversity, structure, and function of the intestinal flora. The addition of 6% CP had the most beneficial effect on the intestinal health of largemouth bass. On the other hand, the addition of 15% CP had adverse effects on the intestinal antioxidant capacity and intestinal mucosal barrier function of largemouth bass.

CONCLUSION

Adding 6-9% CP to the feed for largemouth bass can improve their intestinal health without having a significant impact on their growth performance. CP could serve as a novel prebiotic and immunostimulant ingredient in aquafeed. © 2023 Society of Chemical Industry.

The anticancer effect of potential probiotic L. fermentum and L. plantarum in combination with 5-fluorouracil on colorectal cancer cells

5-Fluorouracil (5-FU) is an effective chemotherapy drug in the treatment of colorectal cancer (CRC). However, auxiliary or alternative therapies must be sought due to its resistance and potential side effects. Certain probiotic metabolites exhibit anticancer properties. In this study evaluated the anticancer and potential therapeutic activities of cell extracts potential probiotic strains, Limosilactobacillus fermentum and Lactiplantibacillus plantarum isolated from the mule milk and the standard probiotic strain Lacticaseibacillus rhamnosus GG (LGG) against the human colon cancer cell line (HT-29) and the normal cell line (HEK-293) alone or in combination with 5-FU. In this study, L. plantarum and L. fermentum, which were isolated from mule milk, were identified using biochemical and molecular methods. Their probiotic properties were investigated in vitro and compared with the standard probiotic strain of the species L. rhamnosus GG. The MTT assay, acridine orange/ethidium bromide (AO/EB) fluorescent staining, and flow cytometry were employed to measure the viability of cell lines, cell apoptosis, and production rates of Th17 cytokines, respectively. The results demonstrated that the combination of lactobacilli cell extracts and 5-FU decreased cell viability and induced apoptosis in HT-29 cells. Furthermore, this combination protected HEK-293 cells from the cytotoxic effects of 5-FU, enhancing their viability and reducing apoptosis. Moreover, the combination treatment led to an increase in the levels of IL-17A, IFN-γ, and TNF-α, which can enhance anti-tumor immunity. In conclusion, the cell extracts of the lactobacilli strains probably can act as a potential complementary anticancer therapy.

The effects of enrofloxacin exposure on responses to oxidative stress, intestinal structure and intestinal microbiome community of largemouth bass (Micropterus salmoides)

Antibiotic residues in the aquaculture environments may lead to antibiotic resistance, and potentially exert adverse effects on health of the non-target organisms and humans. In order to evaluate the effect of enrofloxacin of environmental concentrations on largemouth bass (Micropterus salmoides). Two hundred and seventy largemouth basses (with an average weight of 7.88 ± 0.60 g) were randomly divided into three groups, and separately exposed to 0, 1, 100 μg/L enrofloxacin (Control, ENR1, ENR100) for 30 days to detect the effect of enrofloxacin on the growth performance, oxidative stress, intestinal microbiota structure, inflammatory response and structure of the intestine. The results showed that ENR significantly reduced the final body weight (FBW) and weight gain rate (WGR), and increased feed conversion ratio (FCR) (P < 0.05). The histopathological analysis revealed that the villus width and muscular thickness of anterior intestine were significantly decreased with the increasing of enrofloxacin concentration. The activity of SOD was significantly increased at enrofloxacin stress, while CAT and POD activity were significantly decreased compared to control group (P < 0.05). The activities of lysozyme (LZM), alkaline phosphatase (AKP) and peroxidase (POD) in ENR1 was higher than that of control and ENR100 groups. Enrofloxacin treatment up-regulated the expression IL-1β and TNF-α, and down-regulated IL-10, and decreasing the expression level ZO-1, claudin-1, and occludin. Furthermore, the enrofloxacin treatment significantly decreased the intestinal bacterial diversity (P < 0.05). Exposure to 100 μg/L enrofloxacin obviously increased the relative abundance of Bacteroidota, Myxococcota, and Zixibacteria of fish gut, and reduced Firmicutes; 1 μg/L enrofloxacin considerably increased Bacteroidota, Myxococcota, and Actinobacteria, and reduced Firmicutes. The relative abundance of DTB120 and Elusimicrobiota was positively correlated with the occludin and claudin-1 gene. Taken together, exposure to enrofloxacin inhibited the growth of largemouth bass, influenced intestinal health, and induced dysbiosis of the intestinal microbiota.

A Concise Review: Nutritional Interventions for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)

Wuhan, China reported a novel coronavirus-related sickness in late 2019, which quickly spread into a global epidemic. One crucial factor in combating the coronavirus infection appears to be the presence of a robust, long-lasting, and active immune system. The immune response is affected by several factors, including food. Nutritional insufficiency can cause immune deficits, making infections more likely to cause fatality. Thus, understanding numerous behaviors, particularly dietary habits, is essential to determining their capacity to reduce severe acute respiratory syndrome coronavirus 2 risks and improve prognosis. In this paper, the authors summarize the complex interaction between nutritional status and severe acute respiratory syndrome corona virus 2 infections, as well as the consequences of poor nutrients with regard of the extent to which disease is affected. The literature was compiled by searching a number of reputable scientific databases including Scopus, Science Direct, Springer, Nature, PubMed, Web of Science resources. The accumulating evidence demonstrates that malnutrition impairs the immune system's ability to function, weakening the body's infection resistance. This review emphasizes the significance of nutritional status in the care of coronavirus disease patients as well as demonstrates that functional foods may contribute to better outcomes. Ageing, Obesity, Malnutrition, Undernutrition, Lack of exercise are having a devastating effect on people's health in general and during this coronavirus disease. The severity and prognosis of coronavirus illness seem to be significantly influenced by lifestyle choices, nutritional imbalances, and impaired immune response.

Alterations of gut microbiota biodiversity and relative abundance in women with PCOS: A systematic review and meta-analysis

BACKGROUND

Numerous studies have implicated that the gut microbiota is associated with polycystic ovary syndrome (PCOS). However, a comprehensive data-based summary shown that the effects of the PCOS on the gut microbiota is minimal. We aim to assess the alterations of gut microbiota in women with PCOS.

METHODS

An electronic search of PubMed, Web of Science, Embase, Cochrane Library and Ovid was conducted for eligible studies published from inception to 28 March 2023, without any language or regional restrictions. We used Newcastle-Ottawa Quality Assessment Scale (NOS) to complete the assessment of the risk of bias and Stata 15.1 software to performed meta-analysis.

RESULTS

There were 19 human observational studies in total with 617 women with PCOS and 439 healthy individuals were identified. Compared to the control group, the Chao index (WMD -28.88, 95% CI -45.78 to -11.98, I2 = 100%), Shannon index (WMD -0.11, 95% CI -0.18 to 0.00, I2 = 92.2%); and observed operational taxonomic units (OTUs) counts (WMD - 23.48, 95% CI -34.44 to -12. 53, I2 = 99.6%) were significantly lower in women with PCOS. The relative abundance of Bacteroidaceae was significantly higher (WMD 0.12, 95% CI 0.02 to 0.22, I2 = 9.2%), however there were no statistical differences in Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, Alcaligenaceae, Bifidobacteriaceae, Clostridiaceae, Enterobacteriaceae, Lachnospiraceae, Prevotellaceae, Ruminococcaceae, Veillonellaceae, Bacteroides, Bifidobacterium, Blautia, Dialister, Escherichia-Shigella, Faecalibacterium, Lachnoclostridium, Lachnospira, Megamonas, Phascolarctobacterium, Prevotella, Roseburia, and Subdoligranulum.

CONCLUSION

We demonstrated the alpha diversity of gut microbiota and the relative abundance of Bacteroidaceae in women with PCOS are altered. The results indicates that dysbiosis may be a potential pathogenetic factor in PCOS and provided reliable information to investigate the role of gut microbiota in the development and progression of PCOS.

Gut Fungal Communities Are Influenced by Seasonality in Captive Baikal Teal (Sibirionetta formosa) and Common Teal (Anas crecca)

Understanding the dynamics of avian gut fungal communities and potentially pathogenic species across different seasons is crucial for assessing their health and ecological interactions. In this study, high-throughput sequencing was employed to examine the changes in gut fungal communities and the presence of potential pathogens between different seasons in captive Baikal teal and common teal. Between the summer and autumn seasons, both duck species showed significant differences in fungal diversity and community composition. A higher fungal diversity in both species was exhibited in the summer than in the autumn. Ascomycota and Basidiomycota were the two most common phyla, with a greater proportion of Ascomycota than Basidiomycota in both duck species in the summer. Interestingly, our study also identified animal pathogens and plant saprotrophs in the gut fungal communities. Seasonal variation had an effect on the diversity and abundance of both animal pathogens and saprotrophs. Specifically, during the summer season, the diversity and relative abundance were higher compared to the autumn season. In addition, there were differences between duck species in terms of animal pathogens, while no significant differences were observed in saprotrophs. Overall, the communities of the gut fungi, animal pathogens, and saprotrophs were found to be influenced by seasonal changes rather than host species. Therefore, seasonal variations might dominate over host genetics in shaping the gut microbiota of captive Baikal teal and common teal. This study underscores the importance of incorporating an understanding of seasonal dynamics and potential pathogens within the gut microbiota of captive ducks. Such considerations have the potential to drive progress in the development of sustainable and economically viable farming practices.

Oral delivery of porous starch-loaded bilayer microgels for controlled drug delivery and treatment of ulcerative colitis

We prepared one type of bilayer microgels for oral administration with three effects: pH responsiveness, time lag, and colon enzyme degradation. Combined with the dual biological effects of curcumin (Cur) for reducing inflammation and promoting repair of colonic mucosal injury, targeted colonic localization and release of Cur according to the colonic microenvironment were enhanced. The inner core, derived from guar gum and low-methoxyl pectin, afforded colonic adhesion and degradation behavior; the outer layer, modified by alginate and chitosan via polyelectrolyte interaction, achieved colonic localization. The porous starch (PS)-mediated strong adsorption allowed Cur loading in inner core to achieve a multifunctional delivery system. In vitro, the formulations exhibited good bioresponses at different pH conditions, potentially delaying Cur release in the upper gastrointestinal tract. In vivo, dextran sulfate sodium-induced ulcerative colitis (UC) symptoms were significantly alleviated after oral administration, accompanied by reduced levels of inflammatory factors. The formulations facilitated colonic delivery, allowing Cur accumulation in colonic tissue. Moreover, the formulations could alter gut microbiota composition in mice. During Cur delivery, each formulation increased species richness, decreased pathogenic bacterial content, and afforded synergistic effects against UC. These PS-loaded bilayer microgels, exhibiting excellent biocompatibility, multi-bioresponsiveness, and colon targeting, could be beneficial in UC therapy, allowing development into a novel oral formulation.

Molecular Mechanism and Clinical Effects of Probiotics in the Management of Cow's Milk Protein Allergy

Cow's milk protein allergy (CMPA) is the most common food allergy (FA) in infancy, affecting approximately 2% of children under 4 years of age. According to recent studies, the increasing prevalence of FAs can be associated with changes in composition and function of gut microbiota or "dysbiosis". Gut microbiota regulation, mediated by probiotics, may modulate the systemic inflammatory and immune responses, influencing the development of allergies, with possible clinical benefits. This narrative review collects the actual evidence of probiotics' efficacy in the management of pediatric CMPA, with a specific focus on the molecular mechanisms of action. Most studies included in this review have shown a beneficial effect of probiotics in CMPA patients, especially in terms of achieving tolerance and improving symptoms.

Defining the Relationship of Gut Microbiota, Immunity, and Cognition in Early Life-A Narrative Review

Recently, the immune system has been identified as one of the possible main bridges which connect the gut-brain axis. This review aims to examine available evidence on the microbiota-immunity-cognitive relationship and its possible effects on human health early in life. This review was assembled by compiling and analyzing various literature and publications that document the gut microbiota-immune system-cognition interaction and its implications in the pediatric population. This review shows that the gut microbiota is a pivotal component of gut physiology, with its development being influenced by a variety of factors and, in return, supports the development of overall health. Findings from current research focus on the complex relationship between the central nervous system, gut (along with gut microbiota), and immune cells, highlighting the importance of maintaining a balanced interaction among these systems for preserving homeostasis, and demonstrating the influence of gut microbes on neurogenesis, myelin formation, the potential for dysbiosis, and alterations in immune and cognitive functions. While limited, evidence shows how gut microbiota affects innate and adaptive immunity as well as cognition (through HPA axis, metabolites, vagal nerve, neurotransmitter, and myelination).

Effect of the gut microbiota and their metabolites on postoperative intestinal motility and its underlying mechanisms

Gut microbiota is closely related to human health and disease because, together with their metabolites, gut microbiota maintain normal intestinal peristalsis. The use of antibiotics or opioid anesthetics, or both, during surgical procedures can lead to dysbiosis and affect intestinal motility; however, the underlying mechanisms are not fully known. This review aims to discuss the effect of gut microbiota and their metabolites on postoperative intestinal motility, focusing on regulating the enteric nervous system, 5-hydroxytryptamine neurotransmitter, and aryl hydrocarbon receptor.

A Bibliometric Analysis on the Research Trend of Exercise and the Gut Microbiome

This article aims to provide an overview of research hotspots and trends in exercise and the gut microbiome, a field which has recently gained increasing attention. The relevant publications on exercise and the gut microbiome were identified from the Web of Science Core Collection database. The publication types were limited to articles and reviews. VOSviewer 1.6.18 (Centre for Science and Technology Studies, Leiden University, Leiden, the Netherlands) and the R package "bibliometrix" (R Foundation: Vienna, Austria) were used to conduct a bibliometric analysis. A total of 327 eligible publications were eventually identified, including 245 original articles and 82 reviews. A time trend analysis showed that the number of publications rapidly increased after 2014. The leading countries/regions in this field were the USA, China, and Europe. Most of the active institutions were from Europe and the USA. Keyword analysis showed that the relationship between disease, the gut microbiome, and exercise occurs throughout the development of this field of research. The interactions between the gut microbiota, exercise, status of the host's internal environment, and probiotics, are important facets as well. The research topic evolution presents a trend of multidisciplinary and multi-perspective comprehensive analysis. Exercise might become an effective intervention for disease treatment by regulating the gut microbiome. The innovation of exercise-centered lifestyle intervention therapy may become a significant trend in the future.

Changes of intestinal microbiota in the giant salamander (Andrias davidianus) during growth based on high-throughput sequencing

Despite an increasing appreciation of the importance of host–microbe interaction in healthy growth, information on gut microbiota changes of the Chinese giant salamander (Andrias davidianus) during growth is still lacking. Moreover, it is interesting to identify gut microbial structure for further monitoring A. davidianus health. This study explored the composition and functional characteristics of gut bacteria in different growth periods, including tadpole stage (ADT), gills internalization stage (ADG), 1 year age (ADY), 2 year age (ADE), and 3 year age (ADS), using high-throughput sequencing. The results showed that significant differences were observed in microbial community composition and abundance among different growth groups. The diversity and abundance of intestinal flora gradually reduced from larvae to adult stages. Overall, the gut microbial communities were mainly composed of Fusobacteriota, Firmicutes, Bacteroidota, and Proteobacteria. More specifically, the Cetobacterium genus was the most dominant, followed by Lactobacillus and Candidatus Amphibiichlamydia. Interestingly, Candidatus Amphibiichlamydia, a special species related to amphibian diseases, could be a promising indicator for healthy monitoring during A. davidianus growth. These results could be an important reference for future research on the relationship between the host and microbiota and also provide basic data for the artificial feeding of A. davidianus.

Dietary fungi in cancer immunotherapy: From the perspective of gut microbiota

Immunotherapies are recently emerged as a new strategy in treating various kinds of cancers which are insensitive to standard therapies, while the clinical application of immunotherapy is largely compromised by the low efficiency and serious side effects. Gut microbiota has been shown critical for the development of different cancer types, and the potential of gut microbiota manipulation through direct implantation or antibiotic-based depletion in regulating the overall efficacy of cancer immunotherapies has also been evaluated. However, the role of dietary supplementations, especially fungal products, in gut microbiota regulation and the enhancement of cancer immunotherapy remains elusive. In the present review, we comprehensively illustrated the limitations of current cancer immunotherapies, the biological functions as well as underlying mechanisms of gut microbiota manipulation in regulating cancer immunotherapies, and the benefits of dietary fungal supplementation in promoting cancer immunotherapies through gut microbiota modulation.

New insights into the mechanisms of high-fat diet mediated gut microbiota in chronic diseases

High-fat diet (HFD) has been recognized as a primary factor in the risk of chronic disease. Obesity, diabetes, gastrointestinal diseases, neurodegenerative diseases, and cardiovascular diseases have long been known as chronic diseases with high worldwide incidence. In this review, the influences of gut microbiota and their corresponding bacterial metabolites on the mechanisms of HFD-induced chronic diseases are systematically summarized. Gut microbiota imbalance is also known to increase susceptibility to diseases. Several studies have proven that HFD has a negative impact on gut microbiota, also exacerbating the course of many chronic diseases through increased populations of Erysipelotrichaceae, facultative anaerobic bacteria, and opportunistic pathogens. Since bile acids, lipopolysaccharide, short-chain fatty acids, and trimethylamine N-oxide have long been known as common features of bacterial metabolites, we will explore the possibility of synergistic mechanisms among those metabolites and gut microbiota in the context of HFD-induced chronic diseases. Recent literature concerning the mechanistic actions of HFD-mediated gut microbiota have been collected from PubMed, Google Scholar, and Scopus. The aim of this review is to provide new insights into those mechanisms and to point out the potential biomarkers of HFD-mediated gut microbiota.

The Role of Gut Microbiota in the Pathogenesis of Alzheimer’s Disease

As a degenerative disease of the central nervous system, Alzheimer’s disease (AD) is featured by mental and behavioral dysfunction, and progressive memory loss, which is the most common type of dementia. The incidence of AD is increasing as life expectancy is prolonged, but the pathogenesis of AD remains largely unknown. Recently, the role of gut microbiota in the pathogenesis of AD has drawn increasing attention. The composition of gut microbiota varies across age groups, and the changes in the microbiota metabolites may influence the central nervous system via the brain-gut axis. So far, it has been confirmed that gut bacteria are involved in various pathogenic mechanisms of AD, including amyloid β-protein deposition, Tau protein hyperphosphorylation, neuroinflammation, oxidative stress injury, increased blood-brain barrier permeability, neurotransmitter imbalance, reduced generation of brain-derived neurotrophic factor, and insulin resistance. An important direction of research is to investigate the regulation of gut microbiota for the prevention and treatment of AD.

Associations between Changes in Fat-Free Mass, Fecal Microbe Diversity, and Mood Disturbance in Young Adults after 10-Weeks of Resistance Training

BACKGROUND

The gut microbiome contributes to numerous physiological processes in humans, and diet and exercise are known to alter both microbial composition and mood. We sought to explore the effect of a 10-week resistance training (RT) regimen with or without peanut protein supplementation (PPS) in untrained young adults on fecal microbiota and mood disturbance (MD).

METHODS

Participants were randomized into PPS (n = 25) and control (CTL [no supplement]; n = 24) groups and engaged in supervised, full-body RT twice a week. Measures included body composition, fecal microbe relative abundance, alpha- and beta-diversity from 16 s rRNA gene sequencing with QIIME2 processing, dietary intake at baseline and following the 10-week intervention, and post-intervention MD via the profile of mood states (POMS) questionnaire. Independent samples t-tests were used to determine differences between PPS and CTL groups. Paired samples t-tests investigated differences within groups.

RESULTS

Our sample was mostly female (69.4%), white (87.8%), normal weight (body mass index 24.6 ± 4.2 kg/m²), and 21 ± 2.0 years old. Shannon index significantly increased from baseline in all participants (p = 0.040), with no between-group differences or pre-post beta-diversity dissimilarities. Changes in Blautia abundance were associated with the positive POMS subscales, Vigor and self-esteem-related-affect (SERA) (rho = -0.451, p = 0.04; rho = -0.487, p = 0.025, respectively). Whole tree phylogeny changes were negatively correlated with SERA and Vigor (rho = -0.475, p = 0.046; rho = -0.582, p = 0.011, respectively) as well as change in bodyfat percentage (rho = -0.608, p = 0.007). Mediation analysis results indicate changes in PD Whole Tree Phylogeny was not a significant mediator of the relationship between change in fat-free mass and total MD.

CONCLUSIONS

Mood state subscales are associated with changes in microbial taxa and body composition. PD Whole Tree Phylogeny increased following the 10-week RT regimen; further research is warranted to explore how RT-induced changes in microbial diversity are related to changes in body composition and mood disturbance.

Dynamic changes of gut fungal community in horse at different health states

Accumulating studies indicated that gut microbial changes played key roles in the progression of multiple diseases, which seriously threaten the host health. Gut microbial dysbiosis is closely associated with the development of diarrhea, but gut microbial composition and variability in diarrheic horses have not been well characterized. Here, we investigated gut fungal compositions and changes in healthy and diarrheic horses using amplicon sequencing. Results indicated that the alpha and beta diversities of gut fungal community in diarrheal horses changed significantly, accompanied by distinct changes in taxonomic compositions. The types of main fungal phyla (Neocallimastigomycota, Ascomycota, and Basidiomycota) in healthy and diarrheal horses were same but different in relative abundances. However, the species and abundances of dominant fungal genera in diarrheal horses changed significantly compared with healthy horses. Results of Metastats analysis indicated that all differential fungal phyla (Blastocladiomycota, Kickxellomycota, Rozellomycota, Ascomycota, Basidiomycota, Chytridiomycota, Mortierellomycota, Neocallimastigomycota, Glomeromycota, and Olpidiomycota) showed a decreasing trend during diarrhea. Moreover, a total of 175 differential fungal genera were identified for the gut fungal community between healthy and diarrheal horses, where 4 fungal genera increased significantly, 171 bacterial genera decreased dramatically during diarrhea. Among these decreased bacteria, 74 fungal genera even completely disappeared from the intestine. Moreover, this is the first comparative analysis of equine gut fungal community in different health states, which is beneficial to understand the important role of gut fungal community in equine health.

Changes in the gut microbiota of forest musk deer (Moschus berezovskii) during ex situ conservation

Ex situ conservation is an important technique for protecting rare and endangered wildlife, and maintaining stable individual health is crucial to its success. Gut microbiota composition is a critical indicator of animal health and should therefore be closely monitored during ex situ conservation to track impacts on animal health. Forest musk deer (Moschus berezovskii) were historically distributed in Hebei Province, China, however, they are now extinct in the region. Thus, ex situ conservation efforts were conducted in 2016 whereby approximately 50 individuals were artificially migrated from Weinan, Shaanxi to Huailai, Hebei. To monitor gut health of these migrated individuals, we used 16S rRNA high-throughput sequencing technology to examine the microbiota differences between Huailai juvenile and Weinan juvenile groups, and between Huailai adult and Weinan adult groups. Alpha diversity analysis indicated that the richness of microbiota significantly decreased after migration to the Huailai area, and the beta diversity results also showed significant dissimilarity in gut microbial communities, demonstrating the distinct microbial structure differences in the forest musk deer population from the two areas, for both juvenile and adult groups, respectively. In addition, PICRUSt functional profile prediction indicated that the functions of gut digestion and absorption, and degradation of toxic substances were significantly weakened after ex situ conservation. Differences in diet composition between the individuals of the two sites were also observed and the impact of food on gut microbiota compositions within forest musk deer during ex situ conservation was investigated. This study provides a theoretical basis for developing ex situ conservation measures, especially for the protection of forest musk deer.

Gypenoside XLIX Ameliorate High-Fat Diet-Induced Atherosclerosis via Regulating Intestinal Microbiota, Alleviating Inflammatory Response and Restraining Oxidative Stress in ApoE−/− Mice

A high-fat choline diet (HFCD)-induced atherosclerosis model in ApoE−/− mice was established to explore the anti-atherosclerotic effects of gypenoside XLIX (GPE). It was found that HFCD-induced atherosclerotic index such as dyslipidemia, atherosclerotic plaque, inflammation, and gut microbiota dysfunction could be reduced by GPE treatment. GPE treatment could decrease Verrucomicrobia, Proteobacteria, and Actinobacteria abundance, and increase Firmicutes and Bacteroidetes population. Moreover, the Firmicutes/Bacteroidetes ratio increased significantly after treatment with GPE. After treatment with GPE, the relative abundance of trimethylamine-producing intestinal bacteria Clostridioides and Desulfovibrionaceae decreased while butyrate-producing bacteria such as Eubacterium, Roseburia, Bifidobacterium, Lactobacillus, and Prevotella increased significantly. The GPE group demonstrated higher SCFAs concentrations in the fecal sample, such as Acetic Acid, Propionic Acid, and Butyric Acid. Further pathway analysis showed that 29 metabolic pathways were appreciably disturbed during GPE treatment, including citrate cycle (TCA cycle); galactose and glycero-lipid-metabolism biosynthesis of unsaturated fatty acids, fatty acid biosynthesis. This study suggests that the anti-atherosclerotic effect of GPE is related to the substantial changes in intestinal microbiota and anti-inflammatory activity.

In vivo toxicity evaluations of halophenolic disinfection byproducts in drinking water: A multi-omics analysis of toxic mechanisms

Halophenolic disinfection byproducts (DBPs) in drinking water have attracted considerable concerns in recent years due to their wide occurrence and high toxicity. The liver has been demonstrated as a major target organ for several halophenolic DBPs. However, little is known about the underlying mechanisms of liver damage caused by halophenolic DBPs. In this study, 2,4,6-trichlorophenol (TCP), 2,4,6-tribromophenol (TBP) and 2,4,6-triiodiophenol (TIP) were selected as representative halophenolic DBPs and exposed to C57BL/6 mice at an environmentally-relevant concentration (0.5 μg/L) and two toxicological concentrations (10 and 200 μg/L) for 12 weeks. Then, a combination of histopathologic and biochemical examination, liver transcriptome, serum metabolome, and gut microbiome was adopted. It was found that trihalophenol exposure significantly elevated the serum levels of alkaline phosphatase and albumin. Liver inflammation was observed at toxicological concentrations in the histopathological examination. Transcriptome results showed that the three trihalophenols could impact immune-related pathways at 0.5 μg/L, which further contributed to the disturbance of pathways in infectious diseases and cancers. Notably, TBP and TIP had higher immunosuppressive effects than TCP, which might lead to uncontrolled infection and cancer. In terms of serum metabolic profiles, energy metabolism pathway of citrate cycle and amino acid metabolism pathways of valine, leucine, and isoleucine were also significantly affected. Integration of the metabolomic and transcriptomic data suggested that a 12-week trihalophenol exposure could prominently disturb the glutathione metabolism pathway, indicating the impaired antioxidation and detoxification abilities in liver. Moreover, the disorder of the intestinal flora could interfere with immune regulation and host metabolism. This study reveals the toxic effects of halophenolic DBPs on mammalian liver and provides novel insights into the underlying mechanisms of hepatotoxicity.

Therapeutic Benefits and Dietary Restrictions of Fiber Intake: A State of the Art Review

Throughout history, malnutrition and deficiency diseases have been a problem for our planet’s population. A balanced diet significantly influences everyone’s health, and fiber intake appears to play a more important role than previously thought. The natural dietary fibers are a category of carbohydrates in the constitution of plants that are not completely digested in the human intestine. High-fiber foods, such as fruits, vegetables and whole grains, have consistently been highly beneficial to health and effectively reduced the risk of disease. Although the mode of action of dietary fiber in the consumer body is not fully understood, nutritionists and health professionals unanimously recognize the therapeutic benefits. This paper presents the fiber consumption in different countries, the metabolism of fiber and the range of health benefits associated with fiber intake. In addition, the influence of fiber intake on the intestinal microbiome, metabolic diseases (obesity and diabetes), neurological aspects, cardiovascular diseases, autoimmune diseases and cancer prevention are discussed. Finally, dietary restrictions and excess fiber are addressed, which can cause episodes of diarrhea and dehydration and increase the likelihood of bloating and flatulence or even bowel obstruction. However, extensive studies are needed regarding the composition and required amount of fiber in relation to the metabolism of saprotrophic microorganisms from the enteral level and the benefits of the various pathologies with which they can be correlated.

Diet Is a Stronger Covariate than Exercise in Determining Gut Microbial Richness and Diversity

Obesity is a common metabolic disorder caused by a sedentary lifestyle, and a high-fat and a high-glucose diet in the form of fast foods. High-fat diet-induced obesity is a major cause of diabetes and cardiovascular diseases, whereas exercise and physical activity can ameliorate these disorders. Moreover, exercise and the gut microbiota are known to be interconnected, since exercise can increase the gut microbial diversity and contribute to the beneficial health effects. In this context, we analyzed the effect of diet and exercise on the gut microbiota of mice, by next-generation sequencing of the bacterial V4 region of 16S rRNA. Briefly, mice were divided into four groups: chow-diet (CD), high-fat diet (HFD), high-fat diet + exercise (HFX), and exercise-only (EX). The mice underwent treadmill exercise and diet intervention for 8 weeks, followed by the collection of their feces and DNA extraction for sequencing. The data were analyzed using the QIIME 2 bioinformatics platform and R software to assess their gut microbial composition, richness, and diversity. The Bacteroidetes to Firmicutes ratio was found to be decreased manifold in the HFD and HFX groups compared to the CD and EX groups. The gut microbial richness was comparatively lower in the HFD and HFX groups and higher in the CD and EX groups (ACE, Chao1, and observed OTUs). However, the Shannon alpha diversity index was higher in the HFD and HFX groups than in the CD and EX groups. The beta diversity based on Jaccard, Bray-Curtis, and weighted UniFrac distance metrics was significant among the groups, as measured by PERMANOVA. Paraprevotella, Desulfovibrio, and Lactococcus were the differentially abundant/present genera based on the intervention groups and in addition to these three bacteria, Butyricimonas and Desulfovibrio C21c20 were differentially abundant/present based on diet. Hence, diet significantly contributed to the majority of the changes in the gut microbiota.

Polysaccharide Extracts Derived from Defloration Waste of Fruit Pitaya Regulates Gut Microbiota in a Mice Model

Flower thinning is often used during the planting of fruit trees to improve fruit quality and promote large fruit. Flower buds become an agricultural by-product of the planting process. Pitaya (Hylocereus undatus) is a popular fruit in many tropical regions, which is widely cultivated in Southeast Asian countries. Probiotics such as Lactobacillus plantarum have been shown to exhibit an anti-obesity effect by regulating gut microbiota. This study investigated the effect of polysaccharides from pitaya flower buds (PFW) extracted with water on the regulation of gut microbiota and body weight control in mice fed with a high-fat diet. The effects of PFW on the growth of L. plantarum were analyzed and the propagation of L. plantarum was promoted in an aqueous solution containing PFW. In an in vivo study, mice were fed with a high-fat diet supplemented with PFW for 12 weeks; PFW treatment effectively controlled body weight and reduced short bowel syndrome of mice induced by the high-fat diet. Gut microbiota sequencing revealed that Lachnospiraceae and Lactobacillaceae were the main bacteria targeted by PFW. Moreover, transcript analysis demonstrated that PFW alleviated obesity through amino acid metabolism, carbohydrate metabolism, and glycan metabolism. Overall, PFW is a valuable food supplement that can regulate gut microbiota and may have potential to ameliorate the physiological damage caused by a high-fat diet.

Are microbes and metabolites influencing the parental consumption of nestlings' feces in gray-backed shrikes?

The behavioral video recordings of the gray-backed shrike Lanius tephronotus revealed that parent birds eat the feces produced by their nestlings. "Parental nutrition hypothesis" attributes the origin of this behavior to nutrition-recovery and cost-saving, respectively. However, the presence of usable nutrients in the nestlings' feces is unknown because of traditional technology. In this study, we analyzed all the metabolites and the variations in the diversity and content of microbes in the feces of gray-backed shrike nestlings. We aimed to report the changes in microbes and metabolites with the age of nestlings and point out that the parent birds that eat the feces may gain potential nutrition benefits. The results showed that the relative abundances of Proteobacteria, Firmicutes, and Bacteroidota, changed significantly when the nestlings were 6 days old. The relative abundances of 6 probiotics, which are involved in digestion, metabolism, and immunity-related physiological functions, decreased in the nestlings' feces gradually with age; therefore, these probiotics may be obtained by parent birds upon ingestion of the feces of young nestlings. Among the metabolites that were detected, 20 were lipids and some had a role in anti-parasitic functions and wound healing; however, their relative contents decreased with age. These beneficial substances in the nestlings' feces may stimulate the parents to swallow the feces. Moreover, there were many aromatic metabolites in the newly hatched nestlings' feces, but the content of bitter metabolites increased as they grew up. Therefore, our results are in accordance with the nutritional hypothesis.

Zingiber officinale: A Systematic Review of Botany, Phytochemistry and Pharmacology of Gut Microbiota-Related Gastrointestinal Benefits

Ginger (Zingiber officinale Rosc.) is a traditional edible medicinal herb with a wide range of uses and long cultivation history. Fresh ginger (Zingiberis Recens Rhizoma; Sheng Jiang in Chinese, SJ) and dried ginger (Zingiberis Rhizoma; Gan Jiang in Chinese, GJ) are designated as two famous traditional Chinese herbal medicines, which are different in plant cultivation, appearances and functions, together with traditional applications. Previous researches mainly focused on the differences in chemical composition between them, but there was no systematical comparison on the similarity concerning research achievements of the two herbs. Meanwhile, ginger has traditionally been used for the treatment of gastrointestinal disorders, but so far, the possible interaction with human gut microbiota has hardly been considered. This review comprehensively presents similarities and differences between SJ and GJ retrospectively, particularly proposing them the significant differences in botany, phytochemistry and ethnopharmacology, which can be used as evidence for clinical application of SJ and GJ. Furthermore, the pharmacology of gut microbiota-related gastrointestinal benefits has also been discussed in order to explore better ways to prevent and treat gastrointestinal disorders, which can be used as a reference for further research.

Common Inflammatory Mechanisms in COVID-19 and Parkinson's Diseases: The Role of Microbiome, Pharmabiotics and Postbiotics in Their Prevention

In the last decade, metagenomic studies have shown the key role of the gut microbiome in maintaining immune and neuroendocrine systems. Malfunction of the gut microbiome can induce inflammatory processes, oxidative stress, and cytokine storm. Dysfunction of the gut microbiome can be caused by short-term (virus infection and other infectious diseases) or long-term (environment, nutrition, and stress) factors. Here, we reviewed the inflammation and oxidative stress in neurodegenerative diseases and coronavirus infection (COVID-19). Here, we reviewed the renin-angiotensin-aldosterone system (RAAS) involved in the processes of formation of oxidative stress and inflammation in viral and neurodegenerative diseases. Moreover, the coronavirus uses ACE2 receptors of the RAAS to penetrate human cells. The coronavirus infection can be the trigger for neurodegenerative diseases by dysfunction of the RAAS. Pharmabiotics, postbiotics, and next-generation probiotics, are considered as a means to prevent oxidative stress, inflammatory processes, neurodegenerative and viral diseases through gut microbiome regulation.

Protective Effects of Bacillus amyloliquefaciens 40 Against Clostridium perfringens Infection in Mice

This study aimed to investigate the protective effects of Bacillus amyloliquefaciens (BA40) against Clostridium perfringens (C. perfringens) infection in mice. Bacillus subtilis PB6 was utilized as a positive control to compare the protective effects of BA40. In general, a total of 24 5-week-old male C57BL/6 mice were randomly divided into four groups, with six mice each. The BA40 and PB6 groups were orally dosed with resuspension bacteria (1 × 10⁹ CFU/ml) once a day, from day 1 to 13, respectively. In the control and infected groups, the mice were orally pre-treated with phosphate-buffered saline (PBS) (200 μl/day). The mice in the infected groups, PB6 + infected group and BA40 + infected group, were orally challenged with C. perfringens type A (1 × 10⁹ CFU/ml) on day 11, whereas the control group was orally dosed with PBS (200 μl/day). The results showed that the BA40 group ameliorated intestinal structure damage caused by the C. perfringens infection. Furthermore, the inflammatory responses detected in the infected groups which include the concentrations of IL-1β, TNF-α, IL-6, and immunoglobulin G (IgG) in the serum and secretory immunoglobulin (SigA) in the colon, and nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) activity in the jejunum, were also alleviated (P < 0.05) by BA40 treatment. Similarly, cytokines were also detected by quantitative PCR (qPCR) in the messenger RNA (mRNA) levels, and the results were consistent with the enzyme-linked immunosorbent assay (ELISA) kits. Additionally, in the infected group, the mRNA expression of Bax and p53 was increasing and the Bcl-2 expression was decreasing, which was reversed by BA40 and PB6 treatment (P < 0.05). Moreover, the intestinal microbiota imbalance induced by the C. perfringens infection was restored by the BA40 pre-treatment, especially by improving the relative abundance of Verrucomicrobiota (P < 0.05) and decreasing the relative abundance of Bacteroidetes (P < 0.05) in the phyla level, and the infected group increased the relative abundance of some pathogens, such as Bacteroides and Staphylococcus (P < 0.05) in the genus level. The gut microbiota alterations in the BA40 group also influenced the metabolic pathways, and the results were also compared. The purine metabolism, 2-oxocarboxylic acid metabolism, and starch and sucrose metabolism were significantly changed (P < 0.05). In conclusion, our results demonstrated that BA40 can effectively protect mice from C. perfringens infection.

Effects of Andrographolide on Mouse Intestinal Microflora Based on High-Throughput Sequence Analysis

The intestinal flora is a micro-ecosystem that is closely linked to the overall health of the host. We examined the diversity and abundance of intestinal microorganisms in mice following the administration of andrographolide, a component of the Chinese medical herb Andrographis paniculata. Administration of andrographolide produces multiple beneficial effects including anti-inflammatory, antiviral and antibacterial effects but whether it directly influences the gut microbiota is not known. This study investigated whether the oral administration of andrographolide influences the intestinal microbiota and was compared with amoxicillin treatment as a positive control and water only as a negative control. We examined 21 cecal samples and conducted a high-throughput sequencing analysis based on V3-V4 variable region of the 16S rDNA genes. We found that the diversity and abundance of mouse gut microbiota decreased in direct proportion with the amoxicillin dose whereas andrographolide administration did not affect intestinal microbial community structure. The composition of intestinal microbes following andrographolide treatment was dominated by the Firmicutes while Bacteroidetes dominated the amoxicillin treatment group compared with the negative controls. Specifically, the f__Lachnospiraceae_ Unclassified, Lachnospiraceae_ NK4A136_group and Ruminococcaceae_ UCG-014 were enriched with andrographolide administration while Bacteroides, Klebsiella and Escherichia-Shigella significantly increased in the amoxicillin test groups. Amoxicillin administration altered the microbial community composition and structure by increasing the proportion of pathogenic to beneficial bacteria whereas andrographolide administration led to increases in the proportions and abundance of beneficial bacteria. This study provides a theoretical basis for finding alternatives to antibiotics to decrease bacterial resistance and restore intestinal floral imbalances.

Effects of Bifidobacterium Lactis BS01 and Lactobacillus Acidophilus LA02 on cognitive functioning in healthy women

A growing body of research studies the relationship between probiotic bacteria in the gut and the host organism, including the impact on cognitive functioning. Data from human studies are scarce; however, recent studies point toward the beneficial role of probiotics for cognitive functioning. One of the mechanisms involved in this relationship is the probiotic's ability to influence inflammation and immune response. The aim of this initial study was to investigate the effects of probiotic supplementation with Bifidobacterium Lactis BS01 and Lactobacillus Acidophilus LA02 on cognitive functioning in healthy, young adult females. A total of 53 participants aged 19-31 were enrolled, and 38 completed the trial. A 6-week probiotic or placebo treatment was conducted. Five measures of cognitive functioning were applied pre- and post-treatment. Both groups showed general improvement at the second assessment. Contrary to our hypothesis, the placebo group improved slightly, but significantly, in four out of five measures of cognitive functioning, with the exception of the Wisconsin Card Sorting Test (WCST). The supplementation group improved significantly in two measures of the WCST, compared to the placebo group. Similar results have been previously reported. Probiotic supplementation, while not harmful, might not be beneficial for cognition in the healthy population, or at least not universally.

Integrated Bacterial and Fungal Diversity Analysis Reveals the Gut Microbial Alterations in Diarrheic Giraffes

Gut microbiota has been demonstrated to be associated with multiple gastrointestinal diseases, but information regarding the gut microbial alternations in diarrheic giraffe remains scarce. Here, 16S rDNA and ITS gene amplicon sequencing were conducted to investigate the gut microbial composition and variability in diarrheic giraffes. Results demonstrated that Firmicutes and Proteobacteria were the most dominant phyla in the gut bacterial community, whereas Ascomycota and Basidiomycota were observed to be predominant in the gut fungal community regardless of health status. However, the species and relative abundance of preponderant bacterial and fungal genera in healthy and diarrheic giraffes were different. In contrast to the relatively stabilized gut fungal community, gut bacterial community displayed a significant decrease in the alpha diversity, accompanied by distinct changes in taxonomic compositions. Bacterial taxonomic analysis revealed that the relative abundances of eight phyla and 12 genera obviously increased, whereas the relative abundances of two phyla and eight genera dramatically decreased during diarrhea. Moreover, the relative richness of five fungal genera significantly increased, whereas the relative richness of seven fungal genera significantly declined in diarrheic giraffes. Taken together, this study demonstrated that diarrhea could cause significant alternations in the gut microbial composition of giraffes, and the changes in the gut bacterial community were more significant than those in the gut fungal community. Additionally, investigating the gut microbial characteristics of giraffes in different health states is beneficial to provide a theoretical basis for establishing a prevention and treatment system for diarrhea from the gut microbial perspective.

Western diet as a trigger of Alzheimer's disease: From metabolic syndrome and systemic inflammation to neuroinflammation and neurodegeneration

An excess of saturated fatty acids and simple sugars in the diet is a known environmental risk factor of Alzheimer's disease (AD) but the holistic view of the interacting processes through which such diet may contribute to AD pathogenesis is missing. We addressed this need through extensive analysis of published studies investigating the effects of western diet (WD) on AD development in humans and laboratory animals. We reviewed WD-induced systemic alterations comprising metabolic changes, induction of obesity and adipose tissue inflammation, gut microbiota dysbiosis and acceleration of systemic low-grade inflammation. Next we provide an overview of the evidence demonstrating that WD-associated systemic alterations drive impairment of the blood-brain barrier (BBB) and development of neuroinflammation paralleled by accumulation of toxic amyloid. Later these changes are followed by dysfunction of synaptic transmission, neurodegeneration and finally memory and cognitive impairment. We conclude that WD can trigger AD by acceleration of inflammaging, and that BBB impairment induced by metabolic and systemic inflammation play the central role in this process. Moreover, the concurrence of neuroinflammation and Aβ dyshomeostasis, which by reciprocal interactions drive the vicious cycle of neurodegeneration, contradicts Aβ as the primary trigger of AD. Given that in 2019 the World Health Organization recommended focusing on modifiable risk factors in AD prevention, this overview of the sequential, complex pathomechanisms initiated by WD, which can lead from peripheral disturbances to neurodegeneration, can support future prevention strategies.

Polysaccharides Obtained from Cordyceps militaris Alleviate Hyperglycemia by Regulating Gut Microbiota in Mice Fed a High-Fat/Sucrose Diet

Polysaccharides isolated from fungus Cordyceps militaris display multi-biofunctions, such as immunostimulation, down-regulation of hyperlipidemia, and anti-cancer function. The occurrence of obesity and metabolic syndrome is related to the imbalance of gut microbiota. In this study, the effects of C. militaris and its fractions on modifying metabolic syndrome in mice were evaluated. Mice were fed a high-fat/high-sucrose diet (HFSD) for 14 weeks to induce body weight increase and hyperlipidemia symptoms in mice, and then the mice were simultaneously given a HFSD and C. militaris samples for a further 8 weeks. The results indicated that the fruit body, polysaccharides, and cordycepin obtained from C. militaris had different efficacies on regulating metabolic syndrome and gut microbiota in HFSD-treated mice. Polysaccharides derived from C. militaris decreased the levels of blood sugar and serum lipids in mice fed HFSD. In addition, C. militaris-polysaccharide treatment obviously improved intestinal dysbiosis through promoting the population of next generation probiotic Akkermansia muciniphila in the gut of mice fed HFSD. In conclusion, polysaccharides derived from C. militaris have the potential to act as dietary supplements and health food products for modifying the gut microbiota to improve the metabolic syndrome.

Interplay Between Exercise and Gut Microbiome in the Context of Human Health and Performance

Gut microbiota and exercise have recently been shown to be interconnected. Both moderate and intense exercise are typically part of the training regimen of endurance athletes, but they exert different effects on health. Moderate exercise has positive effects on the health of average athletes, such as a reduction in inflammation and intestinal permeability and an improvement in body composition. It also induces positive changes in the gut microbiota composition and in the microbial metabolites produced in the gastrointestinal tract. Conversely, intense exercise can increase gastrointestinal epithelial wall permeability and diminish gut mucus thickness, potentially enabling pathogens to enter the bloodstream. This, in turn, may contribute to the increase in inflammation levels. However, elite athletes seem to have a higher gut microbial diversity, shifted toward bacterial species involved in amino acid biosynthesis and carbohydrate/fiber metabolism, consequently producing key metabolites such as short-chain fatty acids. Moreover, rodent studies have highlighted a bidirectional relationship, with exercise impacting the gut microbiota composition while the microbiota may influence performance. The present review focuses on gut microbiota and endurance sports and how this interconnection depends upon exercise intensity and training. After pointing out the limits of the studies so far available, we suggest that taking into account the microbiota composition and its metabolic contribution to human host health could help in monitoring and modulating athletes' health and performance. Such an integrated approach should help in the design of microbiome-based solutions for health or performance.

Flavonoids and cellular stress: a complex interplay affecting human health

Flavonoid consumption has beneficial effects on human health, however, clinical evidence remains often inconclusive due to high interindividual variability. Although this high interindividual variability has been consistently observed in flavonoid research, the potential underlying reasons are still poorly studied. Especially the knowledge on the impact of health status on flavonoid responsiveness is limited and merits more investigation. Here, we aim to highlight the bidirectional interplay between flavonoids and cellular stress. First, the state-of-the-art concerning inflammatory stress and mitochondrial dysfunction is reviewed and a comprehensive overview of recent in vitro studies investigating the impact of flavonoids on cellular stress, induced by tumor necrosis factor α, lipopolysaccharide and mitochondrial stressors, is given. Second, we critically discuss the influence of cellular stress on flavonoid uptake, accumulation, metabolism and cell responses, which has, to our knowledge, never been extensively reviewed before. Next, we advocate the innovative insight that stratification of the general population based on health status can reveal subpopulations that benefit more from flavonoid consumption. Finally, suggestions are given for the development of future cell models that simulate the physiological micro-environment, including interindividual variability, since more mechanistic research is needed to establish scientific-based personalized food recommendations for specific subpopulations.

The hepatotoxicity of altrazine exposure in mice involves the intestinal microbiota

Atrazine (ATR), a bio accumulative herbicide is frequently used in agriculture to control unwanted weeds. Due to continuous application, atrazine persists in the environment and causes deleterious impacts including neurotoxicity, hepatotoxicity, and gut microbiota disorders. Therefore, this study for the first time reports the variation in the gut microbiota, induction of process of apoptosis and autophagy in mice induced by ATR. Results indicated that TUNEL-positive hepatocytes suggestive of apoptosis were increased in livers of different experimental mice. Results on metabolic analysis in liver tissues indicated an overall change in seventy-six metabolites particularly Uridine 5'-diphosphate, Propenoylcarnitine and Chinenoside V resulting in generation of energy-related metabolic disorders and imbalance of oxidation/autoxidation status. Results on gut microbiome inquisition showed that ATR changed the richness and diversity of gut microbiota of mice and number of Firmicutes. Moreover, results also revealed that ATR induced apoptosis via disruption of apoptotic (Bax, Bcl2, and Casp3) and autophagy (LC3/Map1lc3a, Beclin 1/Becn1 and P62/Sqstm1) genes. Results of our experimental study confirmed that changes in gut microbiota play a significant role in process of gut immune regulation and inflammation via different metabolites. In conclusion, the findings of our study provide a new idea for the involvement of mechanisms of detoxification in liver and inquisition of gut microbiota plays crucial role in regulation of physiological activities through liver-gut axis to mitigate toxic effects in animals.

Personalizing the Care and Treatment of Alzheimer's Disease: An Overview

Alzheimer's disease (AD) is a progressive, complex, and multifactorial neurodegenerative disorder, still without effective and stable therapeutic strategies. Currently, available medications for AD are based on symptomatic therapy, which include acetylcholinesterase (AChE) inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonist. Additionally, medications such as antipsychotic drugs, antidepressants, sedative, and hypnotic agents, and mood stabilizers are used for the management of behavioral and psychological symptoms of dementia (BPSD). Clinical research has been extensively investigated treatments focusing on the hallmark pathology of AD, including the amyloid deposition, tau hyperphosphorylation, neuroinflammation, and vascular changes; however, so far without success, as all new potential drugs failed to show significant clinical benefit. The underlying heterogeneous etiology and diverse symptoms of AD suggest that a precision medicine strategy is required, which would take into account the complex genetic, epigenetic, and environmental landscape of each AD patient. The article provides a comprehensive overview of the literature on AD, the current and potential therapy of both cognitive symptoms as well as BPSD, with a special focus on gut microbiota and epigenetic modifications as new emerging drug targets. Their specific patterns could represent the basis for novel individually tailored approaches aimed to optimize precision medicine strategies for AD prevention and treatment. However, the successful application of precision medicine to AD demands a further extensive research of underlying pathological processes, as well as clinical and biological complexity of this multifactorial neurodegenerative disorder.

Microbiome Analysis Reveals the Dynamic Alternations in Gut Microbiota of Diarrheal Giraffa camelopardalis

The ruminant gut microbial community's importance has been widely acknowledged due to its positive roles in physiology, metabolism, and health maintenance. Diarrhea has been demonstrated to cause adverse effects on gastrointestinal health and intestinal microecosystem, but studies regarding diarrheal influence on gut microbiota in Giraffa camelopardalis have been insufficient to date. Here, this study was performed to investigate and compare gut microbial composition and variability between healthy and diarrheic G. camelopardalis. The results showed that the gut microbial community of diarrheal G. camelopardalis displayed a significant decrease in alpha diversity, accompanied by distinct alterations in taxonomic compositions. Bacterial taxonomic analysis indicated that the dominant bacterial phyla (Proteobacteria, Bacteroidetes, and Firmicutes) and genera (Escherichia Shigella and Acinetobacter) of both groups were the same but different in relative abundance. Specifically, the proportion of Proteobacteria in the diarrheal G. camelopardalis was increased as compared with healthy populations, whereas Bacteroidetes, Firmicutes, Tenericutes, and Spirochaetes were significantly decreased. Moreover, the relative abundance of one bacterial genus (Comamonas) dramatically increased in diarrheic G. camelopardalis, whereas the relative richness of 18 bacterial genera decreased compared with healthy populations. Among them, two bacterial genera (Ruminiclostridium_5 and Blautia) cannot be detected in the gut bacterial community of diarrheal G. camelopardalis. In summary, this study demonstrated that diarrhea could significantly change the gut microbial composition and diversity in G. camelopardalis by increasing the proportion of pathogenic to beneficial bacteria. Moreover, this study first characterized the distribution of gut microbial communities in G. camelopardalis with different health states. It contributed to providing a theoretical basis for establishing a prevention and treatment system for G. camelopardalis diarrhea.

Microbiome analysis reveals gut microbiota alteration in mice with the effect of matrine

Mounting evidence revealed the negative effects of abuse of antibiotic including the induction of decreased immunity and dysbacteriosis. Matrine displayed multiple beneficial effects such as anti-inflammatory, antiviral and antibacterial, but studies of its influence on gut microbiota are still insufficient to report. Here, the present study was conducted to investigate the influence of matrine on the gut microbiota of mice and amoxicillin was used as a positive control. A total of 21 cecal samples were obtained from seven groups for high-throughput sequencing analysis based on V3-V4 variable region of 16S rRNA genes. Results revealed that the diversity and abundance of gut microbiota in mice gradually decreased with the increase of the concentration of amoxicillin, whereas matrine administration did not effect the intestinal microbial community structure. Additionally, amoxicillin and matrine supplementation also caused significant changes in the relative abundance of some intestinal bacteria. Specifically, the ratio of Klebsiella and Corynebacterium_1, Bacteroides and Parasutterella in the amoxicillin treated-group were increased as compared to the control group, whereas Muribaculaceae_unclassified, Alistipes and Lactobacillus were significantly decreased. Conversely, matrine administration significantly increased the proportion of beneficial bacteria such as Ruminiclostridium_9, Lachnospiraceae_NK4A136_group and Ruminococcaceae_unclassified. In conclusion, amoxicillin administration could change the microbial community composition and structure by increasing the proportion of pathogenic to beneficial bacteria, whereas matrine could increase the number of beneficial bacteria. Moreover, this study provides a theoretical basis for finding alternatives to antibiotics to decrease bacterial resistance and intestinal flora imbalance.

Dysbiosis and Alzheimer's Disease: A Role for Chronic Stress?

Alzheimer’s disease (AD) is an incurable, neuropsychiatric, pathological condition that deteriorates the worth of geriatric lives. AD is characterized by aggregated senile amyloid plaques, neurofibrillary tangles, neuronal loss, gliosis, oxidative stress, neurotransmitter dysfunction, and bioenergetic deficits. The changes in GIT composition and harmony have been recognized as a decisive and interesting player in neuronal pathologies including AD. Microbiota control and influence the oxidoreductase status, inflammation, immune system, and the endocrine system through which it may have an impact on the cognitive domain. The altered and malfunctioned state of microbiota is associated with minor infections to complicated illnesses that include psychosis and neurodegeneration, and several studies show that microbiota regulates neuronal plasticity and neuronal development. The altered state of microbiota (dysbiosis) may affect behavior, stress response, and cognitive functions. Chronic stress-mediated pathological progression also has a well-defined role that intermingles at various physiological levels and directly impacts the pathological advancement of AD. Chronic stress-modulated alterations affect the well-established pathological markers of AD but also affect the gut–brain axis through the mediation of various downstream signaling mechanisms that modulate the microbial commensals of GIT. The extensive literature reports that chronic stressors affect the composition, metabolic activities, and physiological role of microbiota in various capacities. The present manuscript aims to elucidate mechanistic pathways through which stress induces dysbiosis, which in turn escalates the neuropathological cascade of AD. The stress–dysbiosis axis appears a feasible zone of work in the direction of treatment of AD.

Microbiome analysis reveals the alterations in gut microbiota in different intestinal segments of Yimeng black goats

Mounting evidence revealed the importance of gut microbiota in host metabolism, immunity and physiology, and health. Yimeng black goats (YBGs) mainly distributed in Shandong province of China, displayed a complicated intestinal microecosystem, but studies of its gut microbiota are still insufficient to report. Therefore, this study was performed with an objective to characterize the intestinal microbial community structure and diversity in the small intestine (duodenum, jejunum and ileum) and cecum of YBGs and investigated the variability of gut microbiota of different intestinal segments. A total of 12 intestinal samples were collected from YBGs for high-throughput sequencing analysis based on V3-V4 variable region of 16S rRNA genes. Our results revealed alterations in gut microbial composition with obvious differences in relative abundance between the different intestinal segments. Additionally, small intestine including duodenum, jejunum and ileum not only displayed higher species abundance and diversity than cecum but also showed a significant difference among the main components of gut microbiota based on the analytical results of alpha and beta diversities. At the phylum level, Firmicutes and Proteobacteria were the most preponderant phyla in all the samples regardless of intestinal sites. Moreover, the microbiota in small intestine was significantly different from cecum, which were characterized by the higher relative abundance of Butyrivibrio_2, Megasphaera, Halomonas, Delftia, Hydrogenophaga, Limnobacter, Pseudoxanthomonas, Novosphingobium, Janibacter and Erythrobacter, whereas the levels of Butyricicoccus, unidentified_Lachnospiraceae, Fusicatenibacter, Akkermansia, Ruminococcaceae_NK4A214_group and Lactobacillus were lower. Overall, this study first characterized the profile of gut microbiota composition in different intestinal sites and provide better insight into intestinal microbial community structure and diversity of YBGs.