Structural modulation of gut microbiota in life-long calorie-restricted mice

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Empagliflozin rescues lifespan and liver senescence in naturally aged mice

Empagliflozin is currently known to decrease blood glucose levels, delay renal failure, and reduce the risk of cardiovascular death and all-cause mortality in patients with type 2 diabetes with cardiovascular disease. However, the effects of empagliflozin on the lifespan and health of naturally aged organisms are unclear. This study was designed to investigate the impacts and potential mechanisms of empagliflozin on lifespan and liver senescence in naturally aged mice. Our study revealed that empagliflozin improved survival and health in naturally aged mice. Empagliflozin extended the median survival of male mice by 5.9%. Meanwhile, empagliflozin improved learning memory and motor balance, decreased body weight, and downregulated the hepatic protein expression of P21, P16, α-SMA, and COL1A1. Empagliflozin modulates the structure of the intestinal flora, increasing the relative abundance of Lachnospiraceae, Ruminococcaceae, Lactobacillus, Blautia, and Muribaculaceae and decreasing the relative abundance of Erysipelotrichaceae, Turicibacter, and Dubosiella in naturally aged mice. Further exploration discovered that empagliflozin increased the concentration of SCFAs, decreased the levels of the inflammatory factors TNF-α, IL-6, and CXCL9, and regulated the PI3K/AKT/P21 and AMPK/SIRT1/NF-κB pathways, which may represent the underlying mechanisms involved in these beneficial hepatic effects. Taken together, the above results indicated that empagliflozin intervention could be considered a potential strategy for extending lifespan and slowing liver senescence in naturally aged mice.

The connection between aging, cellular senescence and gut microbiome alterations: A comprehensive review

The intricate interplay between cellular senescence and alterations in the gut microbiome emerges as a pivotal axis in the aging process, increasingly recognized for its contribution to systemic inflammation, physiological decline, and predisposition to age-associated diseases. Cellular senescence, characterized by a cessation of cell division in response to various stressors, induces morphological and functional changes within tissues. The complexity and heterogeneity of senescent cells, alongside the secretion of senescence-associated secretory phenotype, exacerbate the aging process through pro-inflammatory pathways and influence the microenvironment and immune system. Concurrently, aging-associated changes in gut microbiome diversity and composition contribute to dysbiosis, further exacerbating systemic inflammation and undermining the integrity of various bodily functions. This review encapsulates the burgeoning research on the reciprocal relationship between cellular senescence and gut dysbiosis, highlighting their collective impact on age-related musculoskeletal diseases, including osteoporosis, sarcopenia, and osteoarthritis. It also explores the potential of modulating the gut microbiome and targeting cellular senescence as innovative strategies for healthy aging and mitigating the progression of aging-related conditions. By exploring targeted interventions, including the development of senotherapeutic drugs and probiotic therapies, this review aims to shed light on novel therapeutic avenues. These strategies leverage the connection between cellular senescence and gut microbiome alterations to advance aging research and development of interventions aimed at extending health span and improving the quality of life in the older population.

Probiotic Bacillus subtilis QST713 improved growth performance and enhanced the intestinal health of yellow-feather broilers challenged with coccidia and Clostridium perfringens

In this study, we investigated the effects of dietary supplementation with Bacillus subtilis (QST713) on the performance and intestinal health of yellow feather broilers under Coccidia and Clostridium perfringens (CP) challenge or CP alone. One-day-old yellow-feathered broiler roosters (n = 600) were randomly assigned to 5 groups (6 replicates with 20 roosters per replicate): the Con blank group, the CIC.p group (d24 Coccidia+d28-30 of CP challenge), the CIC.p + BS group (CIC.p +100 mg/kg B. subtilis), the C.p group (d 28-34 of CP challenge), and the C.p +BS group (C.p +100 mg/kg B. subtilis). The experiment lasted 80 d. The birds were evaluated for parameters such as average daily gain (ADG), average daily feed intake (ADFI), feed efficiency (F/G), intestinal lesion score, villus histomorphometry, intestinal tight junctions, inflammatory factors, and cecal microorganisms. The results revealed that 1) C.p. increased the F/G of broilers from 22 to 42 d (P < 0.05), whereas CIC.p. significantly decreased the 42 d and 80 d body weights (BW) and 22-42 d and 1-80 d ADG (P < 0.05) and significantly increased the 22 to 42 d and 1 to 80 d F/G (P < 0.05). The number of intestinal lesions significantly increased at 35 d and 42 d (P < 0.05). CIC.p significantly decreased the jejunum and ileum villus height (VH) and the ileum villus height/crypt depth (P < 0.05) at 35 d. The challenge significantly upregulated the expression of Claudin-1 and IL-4 mRNAs in the jejunum at 35 d and significantly downregulated the expression of IL-10 mRNA in the ileum at 35 d (P < 0.05); the number of unique OTUs in the challenge group decreased significantly after challenge treatment, and the relative abundances of Romboutsia at 35 d and Cladomyces and Lactobacillus at 42 d decreased significantly (P < 0.05). 2) Compared with the challenge groups, the addition of BS decreased the F/G of broilers from 22 to 42 d. Compared with the CIC group, the addition of BS significantly increased the F/G of broilers from 22 to 42 d. Compared with that in the CIC.p group, the addition of BS significantly increased the VH in the jejunum and ileum at 35 d (P < 0.05). Compared with the challenge groups, the BS groups presented significantly lower mRNA expression levels of Claudin-1 (P < 0.05) in the jejunum at 35 d. The Shannon and Chao indices suggested that BS increased the alpha diversity of cecum microorganisms in broilers. Dietary supplementation with B. subtilis can alleviate the damage to intestinal morphology and intestinal barrier function, as well as the altered cecal flora structure in broilers caused by Coccidia and C. perfringens infections.

Intermittent Fasting and Probiotics: Synergistic Modulation of Gut Health for Therapeutic Advantages

Intermittent fasting (IF) is an increasingly popular dietary approach involving alternating fasting and eating periods. This review aims to summarize the growing body of literature demonstrating that IF is a potential nutritional practice that involves alternating periods of fasting and eating and the numerous benefits of IF, especially in the modulation of healthy gut microbiota. The positive impact of intermittent fasting on gut microbiota not only promotes gastrointestinal health but also has far-reaching effects on critical systems throughout the body. Additionally, the evidence presented in this review highlights the significant preventive and therapeutic effects of intermittent fasting on a wide range of disorders. This includes reducing the risk of diabetes, and neurological disorders, alleviating obesity, and enhancing the functioning of the liver, ultimately contributing to the maintenance of metabolic equilibrium. Perhaps most notably, these effects play a substantial role in preventing diabetes, a global health concern of increasing significance. This comprehensive investigation delves into the scientific foundations of intermittent fasting's impact on gut microbiota and its implications for averting chronic diseases, providing valuable insights for future research and therapeutic applications.

Alzheimer's Disease Has Its Origins in Early Life via a Perturbed Microbiome

Alzheimer's disease (AD) is a neurodegenerative disorder with limited therapeutic options. Accordingly, new approaches for prevention and treatment are needed. One focus is the human microbiome, the consortium of microorganisms that live in and on us, which contributes to human immune, metabolic, and cognitive development and that may have mechanistic roles in neurodegeneration. AD and Alzheimer's disease-related dementias (ADRD) are recognized as spectrum disorders with complex pathobiology. AD/ADRD onset begins before overt clinical signs, but initiation triggers remain undefined. We posit that disruption of the normal gut microbiome in early life leads to a pathological cascade within septohippocampal and cortical brain circuits. We propose investigation to understand how early-life microbiota changes may lead to hallmark AD pathology in established AD/ADRD models. Specifically, we hypothesize that antibiotic exposure in early life leads to exacerbated AD-like disease endophenotypes that may be amenable to specific microbiological interventions. We propose suitable models for testing these hypotheses.

Cyclic fasting-mimicking diet in cancer treatment: Preclinical and clinical evidence

In preclinical tumor models, cyclic fasting and fasting-mimicking diets (FMDs) produce antitumor effects that become synergistic when combined with a wide range of standard anticancer treatments while protecting normal tissues from treatment-induced adverse events. More recently, results of phase 1/2 clinical trials showed that cyclic FMD is safe, feasible, and associated with positive metabolic and immunomodulatory effects in patients with different tumor types, thus paving the way for larger clinical trials to investigate FMD anticancer activity in different clinical contexts. Here, we review the tumor-cell-autonomous and immune-system-mediated mechanisms of fasting/FMD antitumor effects, and we critically discuss new metabolic interventions that could synergize with nutrient starvation to boost its anticancer activity and prevent or reverse tumor resistance while minimizing toxicity to patients. Finally, we highlight potential future applications of FMD approaches in combination with standard anticancer strategies as well as strategies to implement the design and conduction of clinical trials.

Blended-protein changes body weight gain and intestinal tissue morphology in rats by regulating arachidonic acid metabolism and secondary bile acid biosynthesis induced by gut microbiota

PURPOSE

The impact of dietary nutrients on body growth performance and the composition of gut microbes and metabolites is well-established. In this study, we aimed to determine whether dietary protein can regulate the physiological indexes and changes the intestinal tissue morphology in rats, and if dietary protein was a crucial regulatory factor for the composition, function, and metabolic pathways of the gut microbiota.

METHOD

A total of thirty male Sprague Dawley (SD) rats (inbred strain, weighted 110 ± 10 g) were randomly assigned to receive diets containing animal-based protein (whey protein, WP), plant-based protein (soybean protein, SP), or a blended protein (soybean-whey proteins, S-WP) for a duration of 8 weeks. To investigate the effects of various protein supplement sources on gut microbiota and metabolites, we performed a high throughput 16S rDNA sequencing association study and fecal metabolomics profiling on the SD rats. Additionally, we performed analyses of growth indexes, serum biochemical indexes, and intestinal morphology.

RESULTS

The rats in S-WP and WP group exhibited a significantly higher body weight and digestibility of dietary protein compared to the SP group (P < 0.05). The serum total protein content of rats in the WP and S-WP groups was significantly higher (P < 0.05) than that in SP group, and the SP group exhibited significantly lower (P < 0.05) serum blood glucose levels compared to the other two groups. The morphological data showed the rats in the S-WP group exhibited significantly longer villus height and shallower crypt depth (P < 0.05) than the SP group. The gut microbial diversity of the SP and S-WP groups exhibited a higher level than that of the WP group, and the microbiomes of the WP and S-WP groups are more similar compared to those of the SP group. The Arachidonic acid metabolism pathway is the most significant KEGG pathway when comparing the WP group and the SP group, as well as when comparing the SP group and the S-WP group.

CONCLUSION

The type of dietary proteins exerted a significant impact on the physiological indices of SD rats. Intake of S-WP diet can enhance energy provision, improve the body's digestion and absorption of nutrients, as well as promote intestinal tissue morphology. In addition, dietary protein plays a crucial role in modulating fecal metabolites by regulating the composition of the gut microbiota. Metabolomics analysis revealed that the changes in the levels of arachidonic acid metabolites and secondary bile acid metabolite induced by Clostridium_sensu_stricto_1 and [Eubacterium]_coprostanoligenes_group maybe the primarily causes of intestinal morphological differences.

Different depths of food restriction and high-fat diet refeeding in mice impact host obesity and metabolic phenotypes with correlative changes in the gut microbiota

Overweight and obesity affect almost 2 billion adults worldwide, and food restriction (FR) is commonly used to reduce body fat. Whether refeeding (Re) after FR at different ages and to different degrees leads to overweight and its possible mechanisms are uncertain. In this study, adult and young mice were both restricted to 15% and 40% of their casual food intake, and then were fed 60% high-fat chow (FR15%-Re, FR40%-Re), whereas the control groups(CON) consumed high-fat or normal food throughout, respectively. The results of the study suggest that mild FR-heavy feeding may lead to more significant abnormal fat accumulation, liver damage, and increased recruitment of intestinal inflammatory factors and immune cells in mice of different ages and involves multiple types of alterations in the gut microbiota. Further fecal transplantation experiments as well as serum and liver enzyme-linked immunosorbent assay experiments preliminarily suggest that the link between lipid metabolism and inflammatory responses and the gut microbiota may be related to the regulation of the gut and live by Lipopolysaccharides(LPS) and Peroxisome Proliferator-Activated Receptor-Alpha(PPAR-α). In addition, our study may also serve as a reference for studying obesity prevention and treatment programs at different ages.

Analysis of the key genes of Lactobacillus reuteri strains involved in the protection against alcohol-induced intestinal barrier damage

Gastrointestinal inflammation and intestinal barrier function have important effects on human health. Alcohol, an important foodborne hazard factor, damages the intestinal barrier, increasing the risk of disease. Lactobacillus reuteri strains have been reported to reduce gastrointestinal inflammation and strengthen the intestinal barrier. In this study, we selected three anti-inflammatory L. reuteri strains to evaluate their role in the protection of the intestinal barrier and their immunomodulatory activity in a mouse model of gradient alcohol intake. Among the three strains tested (FSCDJY33M3, FGSZY33L6, and FCQHCL8L6), L. reuteri FSCDJY33M3 was found to protect the intestinal barrier most effectively, possibly due to its ability to reduce the expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) and increase the expression of tight junction proteins (occludin, claudin-3). Genomic analysis suggested that the protective effects of L. reuteri FSCDJY33M3 may be related to functional genes and glycoside hydrolases associated with energy production and conversion, amino acid transport and metabolism, carbohydrate transport and metabolism, and DNA replication, recombination, and repair. These genes include COG2856, COG1804, COG2071, and COG1061, which encode adenine deaminase, acyl-CoA transferases, glutamine amidotransferase, RNA helicase, and glycoside hydrolases, including GH13_20, GH53, and GH70. Our results identified functional genes that may be related to protection against alcohol-induced intestinal barrier damage, which might be useful for screening lactic acid bacterial strains that can protect the intestinal barrier.

The Gut Microbiome in Aging and Ovarian Cancer

The gut microbiome changes with age and affects regions beyond the gut, including the ovarian cancer tumor microenvironment. In this review summarizing the literature on the gut microbiome in ovarian cancer and in aging, we note trends in the microbiota composition common to both phenomena and trends that are distinctly opposite. Both ovarian cancer and aging are characterized by an increase in proinflammatory bacterial species, particularly those belonging to phylum Proteobacteria and genus Escherichia, and a decrease in short chain fatty acid producers, particularly those in Clostridium cluster XIVa (family Lachnospiraceae) and the Actinobacteria genus Bifidobacterium. However, while beneficial bacteria from family Porphyromonadaceae and genus Akkermansia tend to increase with normal, healthy aging, these bacteria tend to decrease in ovarian cancer, similar to what is observed in obesity or unhealthy aging. We also note a lack in the current literature of research demonstrating causal relationships between the gut microbiome and ovarian cancer outcomes and research on the gut microbiome in ovarian cancer in the context of aging, both of which could lead to improvements to ovarian cancer diagnosis and treatment.

Eating away cancer: the potential of diet and the microbiome for shaping immunotherapy outcome

The gut microbiome (GMB) plays a substantial role in human health and disease. From affecting gut barrier integrity to promoting immune cell differentiation, the GMB is capable of shaping host immunity and thus oncogenesis and anti-cancer therapeutic response, particularly with immunotherapy. Dietary patterns and components are key determinants of GMB composition, supporting the investigation of the diet-microbiome-immunity axis as a potential avenue to enhance immunotherapy response in cancer patients. As such, this review will discuss the role of the GMB and diet on anti-cancer immunity. We demonstrate that diet affects anti-cancer immunity through both GMB-independent and GMB-mediated mechanisms, and that different diet patterns mold the GMB's functional and taxonomic composition in distinctive ways. Dietary modulation therefore shows promise as an intervention for improving cancer outcome; however, further and more extensive research in human cancer populations is needed.

Identification of KRAS mutation-associated gut microbiota in colorectal cancer and construction of predictive machine learning model

Gut microbiota has demonstrated an increasingly important role in the onset and development of colorectal cancer (CRC). Nonetheless, the association between gut microbiota and KRAS mutation in CRC remains enigmatic. We conducted 16S rRNA sequencing on stool samples from 94 CRC patients and employed the linear discriminant analysis effect size algorithm to identify distinct gut microbiota between KRAS mutant and KRAS wild-type CRC patients. Transcriptome sequencing data from nine CRC patients were transformed into a matrix of immune infiltrating cells, which was then utilized to explore KRAS mutation-associated biological functions, including Gene Ontology items and Kyoto Encyclopedia of Genes and Genomes pathways. Subsequently, we analyzed the correlations among these KRAS mutation-associated gut microbiota, host immunity, and KRAS mutation-associated biological functions. At last, we developed a predictive random forest (RF) machine learning model to predict the KRAS mutation status in CRC patients, based on the gut microbiota associated with KRAS mutation. We identified a total of 26 differential gut microbiota between both groups. Intriguingly, a significant positive correlation was observed between Bifidobacterium spp. and mast cells, as well as between Bifidobacterium longum and chemokine receptor CX3CR1. Additionally, we also observed a notable negative correlation between Bifidobacterium and GOMF:proteasome binding. The RF model constructed using the KRAS mutation-associated gut microbiota demonstrated qualified efficacy in predicting the KRAS phenotype in CRC. Our study ascertained the presence of 26 KRAS mutation-associated gut microbiota in CRC and speculated that Bifidobacterium may exert an essential role in preventing CRC progression, which appeared to correlate with the upregulation of mast cells and CX3CR1 expression, as well as the downregulation of GOMF:proteasome binding. Furthermore, the RF model constructed on the basis of KRAS mutation-associated gut microbiota exhibited substantial potential in predicting KRAS mutation status in CRC patients.IMPORTANCEGut microbiota has emerged as an essential player in the onset and development of colorectal cancer (CRC). However, the relationship between gut microbiota and KRAS mutation in CRC remains elusive. Our study not only identified a total of 26 gut microbiota associated with KRAS mutation in CRC but also unveiled their significant correlations with tumor-infiltrating immune cells, immune-related genes, and biological pathways (Gene Ontology items and Kyoto Encyclopedia of Genes and Genomes pathways). We speculated that Bifidobacterium may play a crucial role in impeding CRC progression, potentially linked to the upregulation of mast cells and CX3CR1 expression, as well as the downregulation of GOMF:Proteasome binding. Furthermore, based on the KRAS mutation-associated gut microbiota, the RF model exhibited promising potential in the prediction of KRAS mutation status for CRC patients. Overall, the findings of our study offered fresh insights into microbiological research and clinical prediction of KRAS mutation status for CRC patients.

From gut to liver: unveiling the differences of intestinal microbiota in NAFL and NASH patients

Non-alcoholic fatty liver disease (NAFLD) is increasingly recognized for its global prevalence and potential progression to more severe liver diseases such as non-alcoholic steatohepatitis (NASH). The gut microbiota plays a pivotal role in the pathogenesis of NAFLD, yet the detailed characteristics and ecological alterations of gut microbial communities during the progression from non-alcoholic fatty liver (NAFL) to NASH remain poorly understood. Methods: In this study, we conducted a comparative analysis of gut microbiota composition in individuals with NAFL and NASH to elucidate differences and characteristics. We utilized 16S rRNA sequencing to compare the intestinal gut microbiota among a healthy control group (65 cases), NAFL group (64 cases), and NASH group (53 cases). Random forest machine learning and database validation methods were employed to analyze the data. Results: Our findings indicate a significant decrease in the diversity of intestinal flora during the progression of NAFLD (p < 0.05). At the phylum level, high abundances of Bacteroidetes and Fusobacteria were observed in both NAFL and NASH patients, whereas Firmicutes were less abundant. At the genus level, a significant decrease in Prevotella expression was seen in the NAFL group (AUC 0.738), whereas an increase in the combination of Megamonas and Fusobacterium was noted in the NASH group (AUC 0.769). Furthermore, KEGG pathway analysis highlighted significant disturbances in various types of glucose metabolism pathways in the NASH group compared to the NAFL group, as well as notably compromised flavonoid and flavonol biosynthesis functions. The study uncovers distinct microbiota characteristics and microecological changes within the gut during the transition from NAFL to NASH, providing insights that could facilitate the discovery of novel biomarkers and therapeutic targets for NAFLD.

Wet-type grinder-treated okara modulates gut microbiota composition and attenuates obesity in high-fat-fed mice

Wet-type grinder (WG) is a nanofiber technology used to atomize dietary fiber-rich materials. WG-treated okara (WGO) exhibits high dispersion and viscosity similar to those of viscous soluble dietary fibers. Here, we studied the effect of WGO supplementation on obesity and gut microbiota composition in high-fat diet (HFD)-fed mice. WGO intake suppressed body weight gain and fat accumulation, improved glucose tolerance, lowered cholesterol levels, and prevented HFD-induced decrease in muscle mass. WGO supplementation also led to cecum enlargement, lower pH, and higher butyrate production. The bacterial 16S ribosomal RNA genes (16S rDNA) were sequenced to determine the gut microbiota composition of the fecal samples. Sequencing of bacterial 16S rDNA revealed that WGO treatment increased the abundance of butyrate producer Ruminococcus and reduced the abundances of Rikenellaceae, Streptococcaceae, and Prevotellaceae, which are related to metabolic diseases. Metabolomics analysis of the plasma of WGO- and cellulose-treated mice were conducted using ultra-high-performance liquid chromatography-mass spectrometry. Metabolic pathway analysis revealed that the primary bile acid biosynthesis pathway was significantly positively regulated by WGO intake instead of cellulose. These results demonstrate that WG is useful for improving functional properties of okara to prevent metabolic syndromes, including obesity, diabetes, and dyslipidemia.

Lactiplantibacillus plantarum-encapsulated microcapsules prepared from okra polysaccharides improved intestinal microbiota in Alzheimer's disease mice

Background

Okra contains a viscous substance rich in water-soluble material, including fibers, pectin, proteoglycans, gum, and polysaccharides. This study explored the use of okra polysaccharides by microorganisms and their potential to improve microbiota.

Methods

The regulation of microcapsules prepared from okra polysaccharides with or without L. plantarum encapsulation on intestinal microbiota was assessed through 16S metagenomic analysis and short-chain fatty acids (SCFAs) in AppNL-G-F/NL-G-F mice (Alzheimer's disease; AD model).

Results

We found that Lactobacillaceae and Lactobacillus were majorly regulated by microcapsules prepared from okra polysaccharides in AD mice. Similarly, microcapsules prepared from okra polysaccharides with L. plantarum encapsulation markedly elevated the abundance of Lactobacillaceae and Lactobacillus and increased SCFAs in AD mice.

Conclusion

Our results suggest that microcapsules prepared from okra polysaccharides with or without L. plantarum encapsulation may improve intestinal microbiota by elevating Lactobacillus levels in AD mice.

Achieving healthy aging through gut microbiota-directed dietary intervention: Focusing on microbial biomarkers and host mechanisms

BACKGROUND

Population aging has become a primary global public health issue, and the prevention of age-associated diseases and prolonging healthy life expectancies are of particular importance. Gut microbiota has emerged as a novel target in various host physiological disorders including aging. Comprehensive understanding on changes of gut microbiota during aging, in particular gut microbiota characteristics of centenarians, can provide us possibility to achieving healthy aging or intervene pathological aging through gut microbiota-directed strategies.

AIM OF REVIEW

This review aims to summarize the characteristics of the gut microbiota associated with aging, explore potential biomarkers of aging and address microbiota-associated mechanisms of host aging focusing on intestinal barrier and immune status. By summarizing the existing effective dietary strategies in aging interventions, the probability of developing a diet targeting the gut microbiota in future is provided.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review is focused on three key notions: Firstly, gut microbiota has become a new target for regulating health status and lifespan, and its changes are closely related to age. Thus, we summarized aging-associated gut microbiota features at the levels of key genus/species and important metabolites through comparing the microbiota differences among centenarians, elderly people and younger people. Secondly, exploring microbiota biomarkers related to aging and discussing future possibility using dietary regime/components targeted to aging-related microbiota biomarkers promote human healthy lifespan. Thirdly, dietary intervention can effectively improve the imbalance of gut microbiota related to aging, such as probiotics, prebiotics, and postbiotics, but their effects vary among.

A Dual Therapeutic Approach to Diabetes Mellitus via Bioactive Phytochemicals Found in a Poly Herbal Extract by Restoration of Favorable Gut Flora and Related Short-Chain Fatty Acids

Diabetes mellitus (DM), a metabolic and endocrine condition, poses a serious threat to human health and longevity. The emerging role of gut microbiome associated with bioactive compounds has recently created a new hope for DM treatment. UHPLC-HRMS methods were used to identify these compounds in a poly herbal ethanolic extract (PHE). The effects of PHE on body weight (BW), fasting blood glucose (FBG) level, gut microbiota, fecal short-chain fatty acids (SCFAs) production, and the correlation between DM-related indices and gut microbes, in rats were investigated. Chebulic acid (0.368%), gallic acid (0.469%), andrographolide (1.304%), berberine (6.442%), and numerous polysaccharides were the most representative constituents in PHE. A more significant BW gain and a reduction in FBG level towards normal of PHE 600 mg/kg treated rats group were resulted at the end of 28th days of the study. Moreover, the composition of the gut microbiota corroborated the study's hypothesis, as evidenced by an increased ratio of Bacteroidetes to Firmicutes and some beneficial microbial species, including Prevotella copri and Lactobacillus hamster. The relative abundance of Bifidobacterium pseudolongum, Ruminococcus bromii, and Blautia producta was found to decline in PHE treatment groups as compared to diabetic group. The abundance of beneficial bacteria in PHE 600 mg/kg treatment group was concurrently associated with increased SCFAs concentrations of acetate and propionate (7.26 nmol/g and 4.13 nmol/g). The findings of this study suggest a promising approach to prevent DM by demonstrating that these naturally occurring compounds decreased FBG levels by increasing SCFAs content and SCFAs producing gut microbiota.

Protocatechuic acid alleviates TMAO-aggravated atherosclerosis via mitigating inflammation, regulating lipid metabolism, and reshaping gut microbiota

Trimethylamine-N-oxide (TMAO) is a risk factor for atherosclerosis. As a natural phenolic acid, protocatechuic acid (PCA) is abundant in various plant foods. The present study investigated the effect of PCA on TMAO-aggravated atherosclerosis in ApoE-/- mice. The mice were randomly divided into five groups and fed one of the following five diets for 12 weeks: namely a low-fat diet (LFD), a western diet (WD), a WD + 0.2% TMAO diet (WDT), a WDT + 0.5% PCA diet (WDT + LPCA), and a WDT + 1.0% PCA diet (WDT + HPCA). Results demonstrated that dietary TMAO exacerbated the development of atherosclerosis by eliciting inflammation and disturbing lipid metabolism. The diet with PCA at 1% reduced TMAO-induced aortic plaque by 30% and decreased the levels of plasma pro-inflammatory cytokines. PCA also improved lipid metabolism by up-regulating the hepatic gene expression of peroxisome proliferator-activated receptor alpha (PPARα). In addition, PCA supplementation enhanced fecal excretion of fatty acids and decreased hepatic fat accumulation. PCA supplementation favorably modulated gut microbiota by increasing the α-diversity with an increase in the abundance of beneficial genera (Rikenella, Turicibacter, Clostridium_sensu_stricto and Bifidobacterium) and a decrease in the abundance of the harmful Helicobacter genus. In summary, PCA could alleviate the TMAO-exacerbated atherosclerosis and inflammation, improve the lipid metabolism, and modulate gut microbiota.

Impact of exercise training on gut microbiome imbalance in obese individuals: a study based on Mendelian randomization analysis

Objective: The aim of this study was to investigate the relationship between exercise and gut Microbiome and to assess its possible causality. Methods: Using Mendelian randomization (MR) research methods, we collected genetic data from different populations, including genetic variants associated with relative abundance or presence of microbial taxa as instrumental variables. At the same time, we extracted results related to obesity and gut Microbiome from existing relevant studies and used inverse variance weighting (IVW), weighted median, and MR-Egger regression to assess the causal relationship between obesity and gut Microbiome. We plotted forest plots and scatter plots of the association between obesity and gut Microbiome. Results: Gut Microbiome was positively associated with obesity, and four bacterial genera (Akkermansia, RuminococcaceaeUCG011, Holdemania, and Intestinimonas) were associated with obesity according to inverse variance-weighted estimation in at least one MR method. Inverse variance weighted estimation showed that obesity was associated with obesity in Akkermansia (OR = 0.810, 95% CI 0.608-1.079, p = 0.04), RuminococcaceaeUCG011 (OR = 1.238, 95% CI 0. 511-2.999, p = 0.04), Holdemania Intestinimonas (OR = 1.214, 95% CI 1.002-1.470, p = 0.03), and Intestinimonas (OR = 0.747, 95% CI 0.514-1.086, p = 0.01) had a relevant effect. Obesity decreased the abundance of Akkermansia, Intestinimonas microbiome and increased the abundance of RuminococcaceaeUCG011, Holdemania microbiome. Conclusion: The results of this study, conducted using a two-sample Mendelian randomization method, suggest a causal relationship between obesity and intestinal microbiome. Obesity decreased the abundance of Akkermansia, Intestinimonas microbiome and increased the abundance of RuminococcaceaeUCG011, Holdemania microbiome. More randomized controlled trials are necessary to elucidate the protective effects of exercise on gut Microbiome and its unique protective mechanisms.

Berberine: Pharmacological Features in Health, Disease and Aging

BACKGROUND

Berberine is the main active compound of different herbs and is defined as an isoquinoline quaternary botanical alkaloid found in barks and roots of numerous plants. It exhibits a wide range of pharmacological effects, such as anti-obesity and antidiabetic effects. Berberine has antibacterial activity against a variety of microbiota, including many bacterial species, protozoa, plasmodia, fungi, and trypanosomes.

OBJECTIVE

This review describes the role of berberine and its metabolic effects. It also discusses how it plays a role in glucose metabolism, fat metabolism, weight loss, how it modulates the gut microbiota, and what are its antimicrobial properties along with its potential side effects with maximal tolerable dosage.

METHODS

Representative studies were considered and analyzed from different scientific databases, including PubMed and Web of Science, for the years 1982-2022.

RESULTS

Literature analysis shows that berberine affects many biochemical and pharmacological pathways that theoretically yield a positive effect on health and disease. Berberine exhibits neuroprotective properties in various neurodegenerative and neuropsychological ailments. Despite its low bioavailability after oral administration, berberine is a promising tool for several disorders. A possible hypothesis would be the modulation of the gut microbiome. While the evidence concerning the aging process in humans is more limited, preliminary studies have shown positive effects in several models.

CONCLUSION

Berberine could serve as a potential candidate for the treatment of several diseases. Previous literature has provided a basis for scientists to establish clinical trials in humans. However, for obesity, the evidence appears to be sufficient for hands-on use.

The gut microbiome modulates associations between adherence to a Mediterranean-style diet, abdominal adiposity, and C-reactive protein in population-level analysis

BACKGROUND

Adherence to a Mediterranean-style dietary pattern is likely to have variable effects on body composition, but the impact of gut microbiome on this relationship is unknown.

OBJECTIVES

To examine the potential mediating effect of the gut microbiome on the associations between Alternate Mediterranean Diet (aMed) scores, abdominal adiposity, and inflammation in population-level analysis.

DESIGN

In a community-based sample aged 25 to 83 y (n = 620; 41% female) from Northern Germany, we assessed the role of the gut microbiome, sequenced from 16S rRNA genes, on the associations between aMed scores, estimated using validated food-frequency questionnaires, magnetic resonance imaging-determined visceral (VAT) and subcutaneous (SAT) adipose tissue and C-reactive protein (CRP).

RESULTS

Higher aMed scores were associated with lower SAT (-0.86 L (95% CI: -1.56, -0.17), P = 0.01), VAT (-0.65 L (95% CI: -1.03,-0.27), P = 0.01) and CRP concentrations (-0.35 mg/L; β: -20.1% (95% CI: 35.5, -1.09), P = 0.04) in the highest versus lowest tertile after multivariate adjustment. Of the taxa significantly associated with aMed scores, higher abundance of Porphyromonadaceae mediated 11.6%, 9.3%, and 8.7% of the associations with lower SAT, VAT, and CRP, respectively. Conversely, a lower abundance of Peptostreptococcaceae mediated 13.1% and 18.2% of the association with SAT and CRP levels. Of the individual components of the aMed score, moderate alcohol intake was associated with lower VAT (-0.2 (95% CI: -0.4, -0.1), P =0.01) with a higher abundance of Oxalobacteraceae and lower abundance of Burkholderiaceae explaining 8.3% and 9.6% of this association, respectively.

CONCLUSION

These novel data suggest that abundance of specific taxa in the Porphyromonadaceae and Peptostreptococcaceae families may contribute to the association between aMed scores, lower abdominal adipose tissue, and inflammation.

The Beneficial Effects of Dietary Interventions on Gut Microbiota-An Up-to-Date Critical Review and Future Perspectives

Different dietary interventions, especially intermittent fasting, are widely used and promoted by physicians; these regimens have been studied lately for their impact on the gut microbiota composition/function and, consequently, on the general physiopathological processes of the host. Studies are showing that dietary components modulate the microbiota, and, at the same time, the host metabolism is deeply influenced by the different products resulting from nutrient transformation in the microbiota compartment. This reciprocal relationship can potentially influence even drug metabolism for chronic drug regimens, significantly impacting human health/disease. Recently, the influence of various dietary restrictions on the gut microbiota and the differences between the effects were investigated. In this review, we explored the current knowledge of different dietary restrictions on animal and human gut microbiota and the impact of these changes on human health.

The Role of Gut Microbiota in Glaucoma Progression and Other Retinal Diseases

As a rapidly growing field, microbiota research offers novel approaches to promoting ocular health and treating major retinal diseases, such as glaucoma. Gut microbiota changes throughout life; however, certain patterns of population changes have been increasingly associated with specific diseases. It has been well established that a disrupted microbiome contributes to central nervous system diseases, including Alzheimer disease, Parkinson disease, multiple sclerosis, and glioma, suggesting a prominent role of microbiome in neurodegenerative diseases. This review summarizes the progress in identifying significant changes in the microbial composition of patients with glaucoma by compiling studies on the association between microbiota and disease progression. Of interest is the relationship between increased Firmicutes/Bacteroidetes ratio in patients with primary open-angle glaucoma, increased taurocholic acid, decreased glutathione, and a reduction in retinal ganglion cell survival. Connecting these microbes to specific metabolites sheds light on the pathogenic mechanism and novel treatment strategies. In summary, the current review synthesizes the findings of several studies investigating the effects of shifting bacterial population in retinal diseases, particularly glaucoma, with the aim to identify the current direction of treatment and help direct future endeavors.

Synergistic Strategies for Gastrointestinal Cancer Care: Unveiling the Benefits of Immunonutrition and Microbiota Modulation

Gastrointestinal (GI) cancers are a group of highly prevalent malignant tumors affecting the gastrointestinal tract. Globally, one in four cancer cases and one in three cancer deaths are estimated to be GI cancers. They can alter digestive and absorption functions, leading to severe malnutrition which may worsen the prognosis of the patients. Therefore, nutritional intervention and monitoring play a fundamental role in managing metabolic alterations and cancer symptoms, as well as minimizing side effects and increasing the effectiveness of chemotherapy. In this scenario, the use of immunonutrients that are able to modulate the immune system and the modification/regulation of the gut microbiota composition have gained attention as a possible strategy to improve the conditions of these patients. The complex interaction between nutrients and microbiota might contribute to maintaining the homeostasis of each individual's immune system; therefore, concurrent use of specific nutrients in combination with traditional cancer treatments may synergistically improve the overall care of GI cancer patients. This work aims to review and discuss the role of immunonutrition and microbiota modulation in improving nutritional status, postoperative recovery, and response to therapies in patients with GI cancer.

The Inhibiting Effects of High-Dose Biochar Application on Soil Microbial Metagenomics and Rice (Oryza sativa L.) Production

Biochar is usually considered as an organic improver which can improve soil and increase crop yields. However, the unrestricted application of biochar to normal-fertility farmland will cause chemical stress on crops and affect agricultural production. At present, the effects and mechanisms of high-dose applications of biochar on rice (Oryza sativa L.) production and soil biological characteristics have not been fully studied. In this greenhouse pot experiment, combined with soil microbial metagenomics, three treatments in triplicates were conducted to explore the responses of rice production, soil chemical properties, and soil biological properties to high-dose applications of biochar (5%, w/w) prepared using peanut waste (peanut hulls and straw). The results show that peanut hulls, with a loose texture and pore structure, are a raw material with stronger effects for preparing biochar than peanut straw in terms of its physical structure. In a rice monoculture system, high-dose applications of biochar (5%, w/w) can slightly increase the grains per spike, while significantly inhibiting the spike number per pot and the percentage of setting. High-dose applications of biochar also have significant negative effects on the diversity and stability of soil bacterial and archaeal communities. Moreover, the microbial metabolism and nutrient cycling processes are also significantly affected by changing the soil carbon/nitrogen ratio. This study discusses the response mechanisms of rice production and soil biology to high-dose biochar applications, and complements the understanding of irrational biochar application on agricultural production and land sustainability.

Lactiplantibacillus plantarum Strain FLPL05 Promotes Longevity in Mice by Improving Intestinal Barrier

This study aimed to evaluate the effect of oral administration of probiotic Lactiplantibacillus plantarum FLPL05 on the lifespan and intestinal barrier of aged mice. L. plantarum FLPL05 significantly prolonged the lifespan of naturally aged mice, maintained the integrity of intestinal mucosal barrier, and reduced the inflammation level. The analysis of intestinal microbiota revealed that L. plantarum FLPL05 increased the relative abundance of Firmicutes and decreased the abundance of Bacteroides, accompanied by the increased proportions of Lactobacillus and Desulfovibrio in intestinal microbiota as well as the reduced proportions of Roseburia and Parabacteroides. The intestinal proteomics revealed that the oral administration of L. plantarum FLPL05 significantly upregulated the tight junction and simultaneously inhibited the expression of apoptotic-related proteins. The immunohistochemistry results also indicated that L. plantarum FLPL05 promoted the expression of tight junction proteins (ZO-1 and occludin) and reduced the apoptosis of intestinal cells. In addition, L. plantarum FLPL05 and the fermented supernatant increased the activity of HT-29. L. plantarum FLPL05 prolonged the lifespan by improving the health of the intestinal tract after aging and may be a potential probiotic and nutritional supplement for the elderly people.

Fecal metabonomics combined with 16S rDNA sequencing to analyze the changes of gut microbiota in rats fed with different protein source diets

PURPOSE

When blended, animal and plant proteins can complement each other in terms of amino acid composition and release time. In this study, we investigated whether the blended protein diet has a better feeding effect than the single protein diet, and to reveal the differences in growth and intestinal microbiota composition caused by the blended protein diet.

METHODS

Forty Sprague Dawley (SD) rats received diets with different protein sources, including casein (C), whey protein (WP), black soybean protein (BSP), and black soybean-whey blended protein (BS-WP), for eight weeks. To investigate the effects of blended protein supplement on gut microbiota and metabolites, we performed a high throughput 16S rDNA sequencing and fecal metabolomics profiling. In addition, we determined growth and serum biochemical indices, and conducted intestinal morphology analyses.

RESULTS

Compared to those in the BSP and WP groups, the daily body weight gain and feed conversion efficiency increased in the BS-WP group. Serum biochemical indices indicated that the protein utilization efficiency of the WP and BS-WP groups was relatively high, and the BS-WP blended protein diet improved the protein adoption rate. The BS-WP blended protein diet also improved intestinal tissue morphology and promoted intestinal villi development compared to the single protein diets. Furthermore, dietary protein altered the composition of gut microbiota, the gut microbial diversity of rats fed with the BS-WP diet was significantly (P < 0.05) higher than that of the other groups. The difference in dietary protein corresponded with an alteration of fecal amino acids and their metabolites, and tryptophan and tyrosine metabolism were the key mechanisms leading to the changes in fecal microbial composition.

CONCLUSION

Dietary protein sources played an important role in the growth and development of rats by influencing intestinal metabolism and microbial composition. The BS-WP blended protein diet was more conducive to nutrient absorption than the single protein diet. Furthermore, blended protein increased the diversity of intestinal microbes and aided the establishment of intestinal barrier function.

Ageing-associated phenotypes in mice

Ageing is a continuous process in life featuring progressive damage accumulation that leads to physiological decline, functional deterioration and ultimately death of an organism. Based on the relatively close anatomical and physiological similarity to humans, the mouse has been proven as a valuable model organism in ageing research over the last decades. In this review, we survey methods and tools currently in use to assess ageing phenotypes in mice. We summarize a range of ageing-associated alterations detectable at two major levels of analysis: (1) physiology and pathophysiology and (2) molecular biomarkers. Age-sensitive phenotypes provided in this article may serve to inform future studies targeting various aspects of organismal ageing in mice. In addition, we discuss conceptual and technical challenges faced by previous ageing studies in mice and, where possible, provide recommendations on how to resolve some of these issues.

The Role of Diet and Gut Microbiota Interactions in Metabolic Homeostasis

Diet is a pivotal determinant in shaping the structure and function of resident microorganisms in the gut through different food components, nutritive proportion, and calories. The effects of diet on host metabolism and physiology can be mediated through the gut microbiota. Gut microbiota-derived metabolites have been shown to regulate glucose and lipid metabolism, energy consumption, and the immune system. On the other hand, emerging evidence indicates that baseline gut microbiota could predict the efficacy of diet intervention, highlighting gut microbiota can be harnessed as a biomarker in personalized nutrition. In this review, the alterations of gut microbiota in different dietary components and dietary patterns, and the potential mechanisms in the diet-microbiota crosstalk are summarized to understand the interactions of diet and gut microbiota on the impact of metabolic homeostasis.

Effect and Correlation of Rosa roxburghii Tratt Juice Fermented by Lactobacillus paracasei SR10-1 on Oxidative Stress and Gut Microflora Dysbiosis in Streptozotocin (STZ)-Induced Type 2 Diabetes Mellitus Mice

Rosa roxburghii Tratt (RRT) is a kind of excellent fruit, with many healthy functions. RRT fruit dietary interventions have demonstrated a remarkable potential to prevent type 2 diabetes mellitus (T2DM). In the present study, the effects of Lactobacillus paracasei SR10-1 fermented RRT juice (FRRT) on the oxidative stress, short-chain fatty acids (SCFAs), and gut microbiota in T2DM mice induced by high-sugar and high-fat diets and streptozotocin (STZ) were investigated using GC-MS and 16S rRNA gene sequencing. The results showed that medium-dose FRRT intervention resulted in significantly decreased levels of TG, TC, LDL-C, BUN, creatinine, and MDA (p < 0.05) and significantly increased levels of HDL-C, GSH-PX, CAT, and SOD of T2DM mice (p < 0.05). The levels of acetic acid, propionic acid, butyric acid, and isovaleric acid were significantly increased, by 142.28%, 428.59%, 1968.66%, and 81.04% (p < 0.05), respectively. The relative abundance of Firmicutes, Lachnospiraceae, Verrucomicrobiaceae, Akkermansia, and Allobaculum was significantly increased (p < 0.05), and the relative abundance of Proteobacteria, Enterobacteriaceae, Veillonellaceae, Phascolarctobacterium, and Klebsiella was significantly decreased (p < 0.05). Correlation analysis showed that Phascolarctobacterium was significantly negatively correlated with weight (p < 0.05), SOD (p < 0.01), CAT (p < 0.05), and T-AOC (p < 0.05). Akkermansia was significantly negatively correlated with weight (p < 0.05). Conclusively, medium-dose FRRT potentially improved T2DM by reversing dyslipidemia, decreasing oxidative stress, increasing SCFAs, and regulating gut microbiota composition. The medium-dose FRRT may serve as a novel T2DM dietary strategy to prevent T2DM.

Molecular Mechanisms and Pathophysiological Pathways of High-Fat Diets and Caloric Restriction Dietary Patterns on Pain

Pain perception provides evolutionary advantages by enhancing the probability of survival, but chronic pain continues to be a significant global health concern in modern society. Various factors are associated with pain alteration. Accumulating evidence has revealed that obesity correlates with enhanced pain perception, especially in chronic pain individuals. Existing dietary patterns related to obesity are primarily high-fat diets (HFD) and calorie restriction (CR) diets, which induce or alleviate obesity separately. HFD has been shown to enhance nociception while CR tends to alleviate pain when measuring pain outcomes. Herein, this review mainly summarizes the current knowledge of the effects of HFD and CR on pain responses and underlying molecular mechanisms of the immunological factors, metabolic regulation, inflammatory processes, Schwann cell (SC) autophagy, gut microbiome, and other pathophysiological signaling pathways involved. This review would help to provide insights on potential nonpharmacological strategies of dietary patterns in relieving pain.

Dietary restriction mitigates the age-associated decline in mouse B cell receptor repertoire diversity

Aging impairs the capacity to respond to novel antigens, reducing immune protection against pathogens and vaccine efficacy. Dietary restriction (DR) extends life- and health span in diverse animals. However, little is known about the capacity of DR to combat the decline in immune function. Here, we study the changes in B cell receptor (BCR) repertoire during aging in DR and control mice. By sequencing the variable region of the BCR heavy chain in the spleen, we show that DR preserves diversity and attenuates the increase in clonal expansions throughout aging. Remarkably, mice starting DR in mid-life have repertoire diversity and clonal expansion rates indistinguishable from chronic DR mice. In contrast, in the intestine, these traits are unaffected by either age or DR. Reduced within-individual B cell repertoire diversity and increased clonal expansions are correlated with higher morbidity, suggesting a potential contribution of B cell repertoire dynamics to health during aging.

Identification of intestinal microbiome associated with lymph-vascular invasion in colorectal cancer patients and predictive label construction

Objective

To identify differences between the composition, abundance, and biological function of the intestinal microbiome of patients with and without lymph-vascular invasion (LVI) colorectal cancer (CRC) and to construct predictive labels to support accurate assessment of LVI in CRC.

Method

134 CRC patients were included, which were divided into two groups according to the presence or absence of LVI, and their intestinal microbiomes were sequenced by 16SrRNA and analyzed for differences. The transcriptome sequencing data of 9 CRC patients were transformed into immune cells abundance matrix by CIBERSORT algorithm, and the correlation among LVI-associated differential intestinal microbiomes, immune cells, immune-related genes and LVI-associated differential GO items and KEGG pathways were analyzed. A random forest (RF) and eXtreme Gradient Boosting (XGB) model were constructed to predict the LVI of CRC patients based on the differential microbiome.

Result

There was no significant difference in α-diversity and β-diversity of intestinal microbiome between CRC patients with and without LVI (P > 0.05). Linear discriminant analysis Effect Size (LEfSe) analysis showed 34 intestinal microbiomes enriched in CRC patients of the LVI group and 5 intestinal microbiomes were significantly enriched in CRC patients of the non-lymph-vascular invasion (NLVI) group. The RF and XGB prediction models constructed with the top 15% of the LVI-associated differential intestinal microbiomes ranked by feature significance had good efficacy.

Conclusions

There are 39 intestinal flora with significantly different species abundance between the LVI and NLVI groups. g:Alistipes.s:Alistipes_indistinctus is closely associated with colorectal cancer vascular invasion. LVI-associated differential intestinal flora may be involved in regulating the infiltration of immune cells in CRC and influencing the expression of immune-related genes. LVI-associated differential intestinal flora may influence the process of vascular invasion in CRC through a number of potential biological functions. RF prediction models and XGB prediction models constructed based on microbial markers of gut flora can be used to predict CRC-LVI conditions.

A nexus of dietary restriction and gut microbiota: Recent insights into metabolic health

In recent times, dietary restriction (DR) has received considerable attention for its promising effects on metabolism and longevity. Previous studies on DR have mainly focused on the health benefits produced by different restriction patterns, whereas comprehensive reviews of the role of gut microbiota during DR are limited. In this review, we discuss the effects of caloric restriction, fasting, protein restriction, and amino acid restriction from a microbiome perspective. Furthermore, the underlying mechanisms by which DR affects metabolic health by regulating intestinal homeostasis are summarized. Specifically, we reviewed the impacts of different DRs on specific gut microbiota. Additionally, we put forward the limitations of the current research and suggest the development of personalized microbes-directed DR for different populations and corresponding next-generation sequencing technologies for accurate microbiological analysis. DR effectively modulates the composition of the gut microbiota and microbial metabolites. In particular, DR markedly affects the rhythmic oscillation of microbes which may be related to the circadian clock system. Moreover, increasing evidence supports that DR profoundly improves metabolic syndrome, inflammatory bowel disease, and cognitive impairment. To summarize, DR may be an effective and executable dietary manipulation strategy for maintaining metabolic health, however, further investigation is needed to elucidate the underlying mechanisms.

Intermittent fasting alleviates type 1 diabetes-induced cognitive dysfunction by improving the frontal cortical metabolic disorder

Intermittent fasting (IF) is an ecological strategy to control various metabolic disorder symptoms, but its protective effect on type 1 diabetes (T1D)-induced cognitive dysfunction and the underlying mechanisms remain poorly defined. Herein, we examined the efficacy of IF in altering the behaviors and brain metabolome in T1D mice and investigated the potential molecular mechanisms. We demonstrated that IF remarkably improved frontal cortical-dependent memory in T1D mice and reduced the loss of neuronal cells. Metabolomics and targeted mass spectrometry assay showed that IF reprogrammed the frontal cortical metabolome composition, including activated the aspartate and glutamate pathway and reversed glycerophospholipid and sphingolipid depositions in T1D mice. Mechanistically, IF attenuated the levels of oxidative stress proteins, such as NOX2, NOX4, 8-OHdG, 4-HNE, and inhibited the levels of pro-apoptotic factors Bax and cleaved Caspase-3, finally improved the memory ability of T1D mice. In vitro studies confirmed the protective effect of the supplemented N-acetylaspartate, a pivotal metabolite involved in IF-regulated T1D-induced cognitive dysfunction, in high glucose-stimulated SH-SY5Y cells by eliminating toxic lipids accumulation, oxidative stress and apoptosis. To conclude, the frontal cortical metabolites mediated the protective effects of IF against T1D-induced cognitive dysfunction by attenuating oxidative stress and apoptotic signaling. Thus, IF can be a potential therapeutic strategy for T1D-induced cognitive dysfunction.

Supplemental enzymes and probiotics on the gut health of broilers fed with a newly harvested corn diet

Gut health is important for digestion and absorption of nutrient for animals. The purpose of this study was to investigate the therapeutic effect of enzymes and probiotics alone or in combination on the gut health of broilers fed with newly harvested corn diets. A total of 624 Arbor Acres Plus male broiler chickens were randomly divided into 8 treatment groups (PC: normal corn diet, NC: newly harvested corn diet, DE: NC + glucoamylase, PT: NC + protease, XL: NC + xylanase, BCC: NC + Pediococcus acidilactici BCC-1, DE + PT: NC + glucoamylase + protease, XL+BCC: NC + xylanase + Pediococcus acidilactici BCC-1). Each group was divided into 6 replicates, with 13 birds each. On d 21, intestinal morphological, intestinal tight junction and aquaporins gene expression, cecal short-chain fatty acid concentrations, and microflora were measured. Compared with the newly harvested corn diets (NC), supplemental glucoamylase (DE) significantly increased the relative abundance of Lachnospiraceae (P < 0.05) and decreased the relative abundance of Moraxellaceae (P < 0.05). Supplemental protease (PT) significantly increased the relative abundance of Barnesiella (P < 0.05), but the relative abundance of Campylobacter decreased by 44.4%. Supplemental xylanase (XL) significantly increased the jejunal mRNA expressions of MUC2, Claudin-1, and Occludin (P < 0.01), as well as the cecal digesta contents of acetic acid, butyric acid, and valeric acid (P < 0.01). Supplemental DE combined with PT increased the ileal mRNA expressions of aquaporins (AQP) 2, AQP5, and AQP7 (P < 0.01). Supplemental BCC significantly increased the jejunal villus height and crypt depth (P < 0.01), the jejunal mRNA expressions of MUC2, Claudin-1 and Occludin (P < 0.01), and the relative abundance of Bacteroides (P < 0.05). Supplemental xylanase in combination with BCC significantly increased jejunal villus height and crypt depth (P < 0.01), the ileal mRNA expressions of AQP2, AQP5 and AQP7 (P < 0.01), and the cecal digesta contents of acetic acid, butyric acid, and valeric acid (P < 0.01). This suggests that inclusions of supplemental protease (12,000 U/kg), glucoamylase (60,000 U/kg), or Pediococcus acidilactici BCC-1 (10⁹ cfu/kg) individually or in combination with xylanase (4,800 U/kg) in the newly harvested corn diets can alleviate diarrhea in broilers, and be beneficial for the gut health.

Combined treatment with glucosamine and chondroitin sulfate improves rheumatoid arthritis in rats by regulating the gut microbiota

BACKGROUND

To investigate the ameliorative effects of glucosamine (GS), chondroitin sulphate (CS) and glucosamine plus chondroitin sulphate (GC) on rheumatoid arthritis (RA) in rats, and to explore the mechanism of GS, CS and GC in improving RA based on the gut microbiota.

METHODS

RA rat models were effectively developed 14 days after CFA injection, and then garaged with GS, CS and GC. Body weight and paw volume of rats were monitored at multiple time points at the beginning of CFA injection. Until D₃₆, serum and ankle tissue specimens were used to measure levels of circulating inflammatory factors (TNF-α, IL-1β, MMP-3, NO and PGE₂) and local inflammatory indicators (TLR-4 and NF-κB). On D₁₈, D₂₅, and D₃₆, intergroup gut microbiota was compared using 16S rRNA gene sequencing and bioinformatics analysis. We also performed the correlation analysis of gut bacteria, joint swelling and inflammatory indicators.

RESULTS

GC, rather than GS and CS, could reduce right paw volumes, levels of TLR-4 and NF-κB in synovial tissues. In addition, enriched genera in RA model rats screened out by LEfSe analysis could be inhibited by GC intervention, including potential LPS-producing bacteria (Enterobacter, Bacteroides, Erysipelotrichaceae_unclassified and Erysipelotrichaceae_uncultured) and some other opportunistic pathogens (Esherichia_Shigella, Nosocomiicoccus, NK4A214_group, Odoribacter, Corynebacterium and Candidatus_Saccharimonas.etc.) that positively correlated with pro-inflammatory cytokines, right paw volume, and pathology scores. Furthermore, the gut microbiota dysbiosis was observed to recover before alleviating joint swelling after interventions.

CONCLUSIONS

GC could inhibit potential LPS-producing bacteria and the activation of TLR-4/NF-κB pathway in RA rats, thus alleviating RA-induced joint injury.

Calorie restriction ameliorates hyperglycemia, modulates the disordered gut microbiota, and mitigates metabolic endotoxemia and inflammation in type 2 diabetic rats

PURPOSE

The effects of calorie restriction (CR) on gut microbiota and the mechanism of CR ameliorating hyperglycemia in streptozotocin (STZ)-induced T2DM model rats were explored.

METHODS

High-fat diet and STZ injection were applied to induce T2DM model rats. Rats were divided into the following three groups: the control-diet ad libitum group, the T2DM model group fed with ad libitum diet, and the T2DM group fed with 30% restriction diet. 16S rRNA sequencing was used to determine the bacterial communities. Lipopolysaccharide (LPS)-binding protein (LBP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were measured.

RESULTS

Glucose tolerance and insulin sensitivity were improved by CR, as well as the levels of fasting and random plasma glucose. Besides, CR not only modulated the overall structure of gut microbiota but also had selective enrichment in anti-inflammatory bacteria such as Lachnospiraceae_NK4A136_group, Ruminococcaceae_9, Allobaculum, Alistipes, and Oscillibacter, and decreased pro-inflammatory pathogenic bacteria such as Bacteroides, Lachnoclostridium, and Bifidobacterium. Tax4Fun indicated that CR could regulate related functional pathways such as lipopolysaccharide biosynthesis, and the plasma levels of LBP, IL-6, and TNF-α were markedly reduced by CR, suggesting the mechanism of CR ameliorating hyperglycemia may associate with the modulation of disordered gut microbiota and the reduction of metabolic endotoxemia and inflammation.

CONCLUSION

CR could ameliorate hyperglycemia, the mechanism of which may associate with the alteration of the overall structure of gut microbiota, restoration of disordered microbiota function, and the downregulation of metabolic endotoxemia and inflammation in diabetic rats.

Impact of caloric restriction on the gut microbiota

Caloric restriction (CR) and related time-restricted diets have been popularized as means of preventing metabolic disease while improving general well-being. However, evidence as to their long-term efficacy, adverse effects, and mechanisms of activity remains incompletely understood. The gut microbiota is modulated by such dietary approaches, yet causal evidence to its possible downstream impacts on host metabolism remains elusive. Herein, we discuss the positive and adverse influences of restrictive dietary interventions on gut microbiota composition and function, and their collective impacts on host health and disease risk. We highlight known mechanisms of microbiota influences on the host, such as modulation of bioactive metabolites, while discussing challenges in achieving mechanistic dietary-microbiota insights, including interindividual variability in dietary responses as well as other methodological and conceptual challenges. In all, causally understanding the impact of CR approaches on the gut microbiota may enable to better decode their overall influences on human physiology and disease.

Fecal Microbiota, Forage Nutrients, and Metabolic Responses of Horses Grazing Warm- and Cool-Season Grass Pastures

Integrating warm-season grasses into cool-season equine grazing systems can increase pasture availability during summer months. The objective of this study was to evaluate effects of this management strategy on the fecal microbiome and relationships between fecal microbiota, forage nutrients, and metabolic responses of grazing horses. Fecal samples were collected from 8 mares after grazing cool-season pasture in spring, warm-season pasture in summer, and cool-season pasture in fall as well as after adaptation to standardized hay diets prior to spring grazing and at the end of the grazing season. Random forest classification was able to predict forage type based on microbial composition (accuracy: 0.90 ± 0.09); regression predicted forage crude protein (CP) and non-structural carbohydrate (NSC) concentrations (p < 0.0001). Akkermansia and Clostridium butyricum were enriched in horses grazing warm-season pasture and were positively correlated with CP and negatively with NSC; Clostridum butyricum was negatively correlated with peak plasma glucose concentrations following oral sugar tests (p ≤ 0.05). These results indicate that distinct shifts in the equine fecal microbiota occur in response different forages. Based on relationships identified between the microbiota, forage nutrients, and metabolic responses, further research should focus on the roles of Akkermansia spp. and Clostridium butyricum within the equine hindgut.

"The Yak"-A remarkable animal living in a harsh environment: An overview of its feeding, growth, production performance, and contribution to food security

Yaks play an important role in the livelihood of the people of the Qinghai-Tibet Plateau (QTP) and contribute significantly to the economy of the different countries in the region. Yaks are commonly raised at high altitudes of ~ 3,000-5,400 m above sea level. They provide many important products, namely, milk, meat, fur, and manure, as well as social status, etc. Yaks were domesticated from wild yaks and are present in the remote mountains of the QTP region. In the summer season, when a higher quantity of pasture is available in the mountain region, yaks use their long tongues to graze the pasture and spend ~ 30-80% of their daytime grazing. The remaining time is spent walking, resting, and doing other activities. In the winter season, due to heavy snowfall in the mountains, pasture is scarce, and yaks face feeding issues due to pasture scarcity. Hence, the normal body weight of yaks is affected and growth retardation occurs, which consequently affects their production performance. In this review article, we have discussed the domestication of yaks, the feeding pattern of yaks, the difference between the normal and growth-retarded yaks, and also their microbial community and their influences. In addition, blood biochemistry, the compositions of the yaks' milk and meat, and reproduction are reported herein. Evidence suggested that yaks play an important role in the daily life of the people living on the QTP, who consume milk, meat, fur, use manure for fuel and land fertilizer purposes, and use the animals for transportation. Yaks' close association with the people's well-being and livelihood has been significant.

Dietary patterns and cardiometabolic health: Clinical evidence and mechanism

For centuries, the search for nutritional interventions to underpin cardiovascular treatment and prevention guidelines has contributed to the rapid development of the field of dietary patterns and cardiometabolic disease (CMD). Numerous studies have demonstrated that healthy dietary patterns with emphasis on food-based recommendations are the gold standard for extending lifespan and reducing the risks of CMD and mortality. Healthy dietary patterns include various permutations of energy restriction, macronutrients, and food intake patterns such as calorie restriction, intermittent fasting, Mediterranean diet, plant-based diets, etc. Early implementation of healthy dietary patterns in patients with CMD is encouraged, but an understanding of the mechanisms by which these patterns trigger cardiometabolic benefits remains incomplete. Hence, this review examined several dietary patterns that may improve cardiometabolic health, including restrictive dietary patterns, regional dietary patterns, and diets based on controlled macronutrients and food groups, summarizing cutting-edge evidence and potential mechanisms for CMD prevention and treatment. Particularly, considering individual differences in responses to dietary composition and nutritional changes in organ tissue diversity, we highlighted the critical role of individual gut microbiota in the crosstalk between diet and CMD and recommend a more precise and dynamic nutritional strategy for CMD by developing dietary patterns based on individual gut microbiota profiles.

The antitumour effects of caloric restriction are mediated by the gut microbiome

Calorie restriction (CR) and intermittent fasting (IF) without malnutrition reduce the risk of cancer development. Separately, CR and IF can also lead to gut microbiota remodelling. However, whether the gut microbiota has a role in the antitumour effect related to CR or IF is still unknown. Here we show that CR, but not IF, protects against subcutaneous MC38 tumour formation through a mechanism that is dependent on the gut microbiota in female mice. After CR, we identify enrichment of Bifidobacterium through 16S rRNA sequencing of the gut microbiome. Moreover, Bifidobacterium bifidum administration is sufficient to rescue the antitumour effect of CR in microbiota-depleted mice. Mechanistically, B. bifidum mediates the CR-induced antitumour effect through acetate production and this effect is also dependent on the accumulation of interferon-γ⁺CD8⁺ T cells in the tumour microenvironment. Our results demonstrate that CR can modulate the gut taxonomic composition, which should be of oncological significance in tumour growth kinetics and cancer immunosurveillance.

Decreased Enterobacteriaceae translocation due to gut microbiota remodeling mediates the alleviation of premature aging by a high-fat diet

Aging-associated microbial dysbiosis exacerbates various disorders and dysfunctions, and is a major contributor to morbidity and mortality in the elderly, but the underlying cause of this aging-related syndrome is confusing. SIRT6 knockout (SIRT6 KO) mice undergo premature aging and succumb to death by 4 weeks, and are therefore useful as a premature aging research model. Here, fecal microbiota transplantation from SIRT6 KO mice into wild-type (WT) mice phenocopies the gut dysbiosis and premature aging observed in SIRT6 KO mice. Conversely, an expanded lifespan was observed in SIRT6 KO mice when transplanted with microbiota from WT mice. Antibiotic cocktail treatment attenuated inflammation and cell senescence in KO mice, directly suggesting that gut dysbiosis contributes to the premature aging of SIRT6 KO mice. Increased Enterobacteriaceae translocation, driven by the overgrowth of Escherichia coli, is the likely mechanism for the premature aging effects of microbiome dysregulation, which could be reversed by a high-fat diet. Our results provide a mechanism for the causal link between gut dysbiosis and aging, and support a beneficial effect of a high-fat diet for correcting gut dysbiosis and alleviating premature aging. This study provides a rationale for the integration of microbiome-based high-fat diets into therapeutic interventions against aging-associated diseases.

Adeno-associated virus vector intraperitoneal injection induces colonic mucosa and submucosa transduction and alters the diversity and composition of the faecal microbiota in rats

Background

Viral vector technology, especially recombinant adeno-associated virus vector (rAAV) technology, has shown great promise in preclinical research for clinical applications. Several studies have confirmed that rAAV can successfully transduce the enteric nervous system (ENS), and rAAV gene therapy has been approved by the Food and Drug Administration (FDA) for the treatment of the early childhood blindness disease Leber congenital amaurosis and spinal muscular atrophy (SMA). However, until now, it has not been possible to determine the effect of AAV9 on intestinal microbiota.

Methods

We examined the efficiency of AAV9-mediated ascending colon, transverse colon and descending colon transduction through intraperitoneal (IP) injection, performed 16S rRNA gene amplicon sequencing and analysed specific faecal microbial signatures following AAV9 IP injection via bioinformatics methods in Sprague-Dawley (SD) rats.

Results

Our results showed (1) efficient transduction of the mucosa and submucosa of the ascending, transverse, and descending colon following AAV9 IP injection; (2) a decreased alpha diversity and an altered overall microbial composition following AAV9 IP injection; (3) significant enrichments in a total of 5 phyla, 10 classes, 13 orders, 15 families, 29 genera, and 230 OTUs following AAV9 IP injection; and (4) AAV9 can significantly upregulate the relative abundance of anaerobic microbiota which is one of the seven high-level phenotypes that BugBase could predict.

Conclusion

In summary, these data show that IP injection of AAV9 can successfully induce the transduction of the colonic mucosa and submucosa and alter the diversity and composition of the faecal microbiota in rats.

SIRT3 deficiency decreases oxidative metabolism capacity but increases lifespan in male mice under caloric restriction

Mitochondrial NAD⁺ -dependent protein deacetylase Sirtuin3 (SIRT3) has been proposed to mediate calorie restriction (CR)-dependent metabolic regulation and lifespan extension. Here, we investigated the role of SIRT3 in CR-mediated longevity, mitochondrial function, and aerobic fitness. We report that SIRT3 is required for whole-body aerobic capacity but is dispensable for CR-dependent lifespan extension. Under CR, loss of SIRT3 (Sirt3^-/- ) yielded a longer overall and maximum lifespan as compared to Sirt3^+/+ mice. This unexpected lifespan extension was associated with altered mitochondrial protein acetylation in oxidative metabolic pathways, reduced mitochondrial respiration, and reduced aerobic exercise capacity. Also, Sirt3^-/- CR mice exhibit lower spontaneous activity and a trend favoring fatty acid oxidation during the postprandial period. This study shows the uncoupling of lifespan and healthspan parameters (aerobic fitness and spontaneous activity) and provides new insights into SIRT3 function in CR adaptation, fuel utilization, and aging.

The effects of elemene emulsion injection on rat fecal microbiota and metabolites: Evidence from metagenomic exploration and liquid chromatography-mass spectrometry

Objective

Elemene emulsion injection (EEI) has been approved for interventional and intracavitary chemotherapy in treating malignant ascites in China, but few studies have focused on the effects of EEI on gut microbiota and metabolites. In this study, we investigated the effects of EEI on the fecal microbiota and metabolites in healthy Sprague-Dawley (SD) rats.

Methods

We randomly assigned 18 male SD rats to three groups (n = 6 in each group): the sham group (group S), the low-concentration EEI group (L-EEI), and the high-concentration EEI group (H-EEI). The L-EEI and H-EEI rats were administered 14 days of consecutive EEI, 20 mg/kg, and 40 mg/kg intraperitoneally (IP). Group S rats were administered the same volume of normal saline. On day 14, each animal's feces were collected for metagenomic sequencing and metabolomic analysis, and the colonic contents were collected for 16S rRNA sequencing.

Results

EEI could alter the β-diversity but not the α-diversity of the fecal microbiota and induce structural changes in the fecal microbiota. Different concentrations of EEI affect the fecal microbiota differently. The effects of different EEI concentrations on the top 20 bacteria with significant differences at the species level among the three groups were roughly divided into three categories: (1) A positive or negative correlation with the different EEI concentrations. The abundance of Ileibacterium Valens increased as the EEI concentration increased, while the abundance of Firmicutes bacteria and Clostridium sp. CAC: 273 decreased. (2) The microbiota showed a tendency to increase first, then decrease or decrease first, and then increase as EEI concentration increased-the abundance of Prevotella sp. PCHR, Escherichia coli, and Candidatus Amulumruptor caecigallinarius tended to decrease with L-EEI but significantly increased with H-EEI. In contrast, L-EEI significantly increased Ruminococcus bromii and Dorea sp. 5-2 abundance, and Oscillibacter sp. 1-3 abundance tended to increase, while H-EEI significantly decreased them. (3) L-EEI and H-EEI decreased the abundance of bacteria (Ruminococcaceae bacterium, Romboutsia ilealis, and Staphylococcus xylosus). Fecal metabolites, like microbiota, were sensitive to different EEI concentrations and correlated with fecal microbiota and potential biomarkers.

Conclusion

This study shows that intraperitoneal EEI modulates the composition of rat fecal microbiota and metabolites, particularly the gut microbiota's sensitivity to different concentrations of EEI. The impact of changes in the microbiota on human health remains unknown, particularly EEI's efficacy in treating tumors.

Caloric Restriction, Friend or Foe: Effects on Metabolic Status in Association with the Intestinal Microbiome and Metabolome

Daily calorie restriction (CR) has shown benefits on weight loss and alleviation of metabolic disorders. We investigated the effects of three CR regimens, i.e., 20% (CR-20), 40% (CR-40), and 60% (CR-60) less than the average daily calorie intake, respectively, on the metabolic parameters, gut microbiome composition, and its related metabolites in healthy mice. Compared with mice fed ad libitum (AL), CR dose-dependently reduced the body weight, and weights of liver and epididymal adipose tissues, and enhanced the insulin sensitivity, glucose tolerance, and lipid homeostasis. Moreover, expression levels of intestinal tight junction proteins (i.e., ZO-1, claudin, and occludin) were significantly promoted by CR than those of AL mice, demonstrating the CR-induced improvement of the intestinal barrier integrity. CR contributed to the enrichment of beneficial microbiota (e.g., Lactobacillus, Bacteroides, and Akkermansia) and increased propionic acid levels. Notably, CR-60 deleteriously caused liver injury, and enhanced hepatic inflammatory cytokines (i.e., IL-1, IL-6, and TNF-α) and lipopolysaccharides, which were accompanied by high levels of trimethylamine (TMA) and trimethylamine oxide (TMAO) in relation to CR-60-altered gut microbiota structure and fecal metabolome. Additionally, we found differential impacts of CR-20, -40, or -60 on amino acid absorption and metabolism. Our findings support the health-promoting benefits of 60-80% daily calorie intake on the metabolic status by regulating the gut microbiota in healthy mice. However, excessive CR caused liver injury and gut microbiota-dependent elevation of TMAO. The differential effects of CR regimens on the intestinal microbiome and fecal metabolome provide novel insights into the dietary pattern-gut microbiome interactions linked with host metabolism.

An Energy-Restricted Diet Including Yogurt, Fruit, and Vegetables Alleviates High-Fat Diet-Induced Metabolic Syndrome in Mice by Modulating the Gut Microbiota

BACKGROUND

The importance of the composition of an energy-restricted diet in the treatment of metabolic syndrome (MetS) is unknown.

OBJECTIVES

In this study we aimed to investigate the benefits of a novel dietary treatment (50% calorie restriction diet composed of yogurt, fruit, and vegetables [CR-YD]) in mice with MetS.

METHODS

Forty 7-wk-old male C57BL/6 J mice were randomly assigned to 4 groups (n = 10/group) that were fed for 14 wk ad libitum with a normal diet (ND; 10%:70%:20% energy from fat: carbohydrate: protein) or for 12 wk with a high-fat diet (HFD; 60:20:20) or the HFD followed by 2 wk of feeding with a 50% calorie-restricted HFD (CR-HFD) or YD (CR-YD, 21.2%:65.4%:13.4% energy). Body weight, fat deposition, hepatic steatosis, serum concentrations of inflammatory biomarkers, and glucose homeostasis were assessed. Fecal microbiota transplantation (FMT) was used to validate the roles of gut microbiota in MetS.

RESULTS

The HFD group had 50% greater body weight and 475% greater fat deposition than the ND group (P < 0.05). Compared with the HFD group, the CR-HFD and CR-YD groups had 22% and 31% lower body weight and 49% and 75% less fat deposition, respectively (P < 0.05). Compared with the CR-HFD group, the CR-YD group had 11% lower body weight, 96% less fat deposition, 500% less hepatic steatosis, 75% lower glucose, and 450% more hepatic Akkermansia bacteria (P < 0.05). The CR-YD group also had 50% lower histopathology scores and 1.35-fold higher levels of Claudin4 than the CR-HFD group (P < 0.05). The HFD + CR-YD fecal group had 10.6% lower body weight, 119% lower steatosis, and 17.9% lower glucose (P < 0.05) than the HFD + CR-HFD fecal group.

CONCLUSIONS

Compared with CR alone, the CR-YD diet has a better therapeutic effect in mice with HFD-induced MetS.