A comparative study of the modulation of the gut microbiota in rats by dietary intervention with different sources of egg-white proteins

Campylobacter jejuni and casein hydrolysate addition: Impact on poultry in vitro cecal microbiota and metabolome

This study investigates the impact of casein hydrolysates on the poultry ceca inoculated with Campylobacter focusing on microbial molecular preferences for different protein sources in the presence of Campylobacter jejuni. Three casein sources (intact casein (IN), casein enzyme hydrolysate (EH), and casein acid hydrolysate (AH)) were introduced to cecal contents in combination with inoculated C. jejuni in an in vitro model system incubated for 48 h at 42°C under microaerophilic conditions. Samples were collected at 0, 24, and 48 h. Genomic DNA was extracted and amplified using custom dual-indexed primers, followed by sequencing on an Illumina MiSeq platform. The obtained sequencing data were then analyzed via QIIME2-2021.11. Metabolite extracts were analyzed with ultra-high-performance liquid orbitrap chromatography-mass spectrometry (UHPLC-MS). Statistical analysis of metabolites was conducted using MetaboAnalyst 5.0, while functional analysis was performed using Mummichog 2.0 with a significance threshold set at P < 0.00001. DNA sequencing and metabolomic analyses revealed that C. jejuni was most abundant in the EH group. Microbial diversity and richness improved in casein supplemented groups, with core microbial differences observed, compared to non-supplemented groups. Vitamin B-associated metabolites significantly increased in the supplemented groups, displaying distinct patterns in vitamin B6 and B9 metabolism between EH and AH groups (P < 0.05). Faecalibacterium and Phascolarctobacterium were associated with AH and EH groups, respectively. These findings suggest microbial interactions in the presence of C. jejuni and casein supplementation are influenced by microbial community preferences for casein hydrolysates impacting B vitamin production and shaping competitive dynamics within the cecal microbial community. These findings underscore the potential of nutritional interventions to modulate the poultry GIT microbiota for improved health outcomes.

Effect of a Probiotic Beverage Enriched with Cricket Proteins on the Gut Microbiota: Composition of Gut and Correlation with Nutritional Parameters

The health and balance of the gut microbiota are known to be linked to diet composition and source, with fermented products and dietary proteins potentially providing an exceptional advantage for the gut. The purpose of this study was to evaluate the effect of protein hydrolysis, using a probiotic beverage enriched with either cricket protein (CP) or cricket protein hydrolysates (CP.Hs), on the composition of the gut microbiota of rats. Taxonomic characterization of the gut microbiota in fecal samples was carried out after a 14-day nutritional study to identify modifications induced by a CP- and CP.H-enriched fermented probiotic product. The results showed no significant differences (p > 0.05) in the diversity and richness of the gut microbiota among the groups fed with casein (positive control), CP-enriched, and fermented CP.H-enriched probiotic beverages; however, the overall composition of the microbiota was altered, with significant modifications in the relative abundance of several bacterial families and genera. In addition, fermented CP.H-enriched probiotic beverages could be related to the decrease in the number of potential pathogens such as Enterococcaceae. The association of gut microbiota with the nutritional parameters was determined and the results showed that digestibility and the protein efficiency ratio (PER) were highly associated with the abundance of several taxa.

Potential Benefits of Egg White Proteins and Their Derived Peptides in the Regulation of the Intestinal Barrier and Gut Microbiota: A Comprehensive Review

Impaired intestinal barrier function can impede the digestion and absorption of nutrients and cause a range of metabolic disorders, which are the main causes of intestinal disease. Evidence suggests that proper dietary protein intake can prevent and alleviate intestinal diseases. Egg white protein (EWP) has received considerable attention, because of its high protein digestibility and rich amino acid composition. Furthermore, bioactive peptides may have an increased repair effect due to their high degradation efficiency in the gut. In this study, we aimed to review the effects of EWP and its bioactive peptides on intestinal structural repair. The potential modulation mechanisms by which EWP and their peptides regulate the gut microbiota and intestinal barrier can be summarized as follows: (1) restoring the structure of the intestinal barrier to its intact form, (2) enhancing the intestinal immune system and alleviating the inflammatory response and oxidative damage, and (3) increasing the relative abundance of beneficial bacteria and metabolites. Further in-depth analysis of the coregulation of multiple signaling pathways by EWP is required, and the combined effects of these multiple mechanisms requires further evaluation in experimental models. Human trials can be considered to understand new directions for development.

Effect of Consumption of Animal Products on the Gut Microbiome Composition and Gut Health

The gut microbiome is critical in human health, and various dietary factors influence its composition and function. Among these factors, animal products, such as meat, dairy, and eggs, represent crucial sources of essential nutrients for the gut microbiome. However, the correlation and characteristics of livestock consumption with the gut microbiome remain poorly understood. This review aimed to delineate the distinct effects of meat, dairy, and egg products on gut microbiome composition and function. Based on the previous reports, the impact of red meat, white meat, and processed meat consumption on the gut microbiome differs from that of milk, yogurt, cheese, or egg products. In particular, we have focused on animal-originated proteins, a significant nutrient in each livestock product, and revealed that the major proteins in each food elicit diverse effects on the gut microbiome. Collectively, this review highlights the need for further insights into the interactions and mechanisms underlying the impact of animal products on the gut microbiome. A deeper understanding of these interactions would be beneficial in elucidating the development of dietary interventions to prevent and treat diseases linked to the gut microbiome.

Effects of different dietary protein levels on intestinal aquaporins in weaned piglets

This study was conducted to investigate the relationship between changes in intestinal aquaporins (AQPs) in piglets fed diets with different protein levels and nutritional diarrhoea in piglets. Briefly, 96 weaned piglets were randomly divided into four groups fed diets with crude protein (CP) levels of 18%, 20%, 22% and 24%. The small intestines and colons of the weaned piglets were collected, and several experiments were conducted. In the small intestine, AQP4 protein expression was higher in weaned piglets fed the higher-CP diets (22% and 24% CP) than in those fed the 20% CP diet except at 72 h (p < 0.01). At 72 h, the AQP4 protein expression in the small intestine was lower in the 18% group than in the other three groups (p < 0.01). Under 20% CP feeding, AQP2, AQP4 and AQP9 protein expression in the colons of piglets peaked at certain time points. The AQP2 and AQP4 mRNA levels in the colon and the AQP4 and AQP4 mRNA levels in the distal colon were approximately consistent with the protein expression levels. However, the AQP9 mRNA content in the colon was highest in the 18% group, and the AQP2 mRNA content in the distal colon was significantly higher in the 24% group than in the 20% group. AQP2 and AQP4 were expressed mainly around columnar cells in the upper part of the smooth colonic intestinal villi, and AQP9 was expressed mainly on columnar cells and goblet cells in the colonic mucosa. In conclusion, 20% CP is beneficial to the normal expression of AQP4 in the small intestine, AQP2, AQP4 and AQP9 in the colon of weaned piglets, which in turn maintains the balance of intestinal water absorption and secretion in piglets.

The Impact of Food Additives on the Abundance and Composition of Gut Microbiota

The gut microbiota has been confirmed as an important part in human health, and is even take as an 'organ'. The interaction between the gut microbiota and host intestinal environment plays a key role in digestion, metabolism, immunity, inflammation, and diseases. The dietary component is a major factor that affects the composition and function of gut microbiota. Food additives have been widely used to improve the color, taste, aroma, texture, and nutritional quality of processed food. The increasing variety and quantity of processed food in diets lead to increased frequency and dose of food additives exposure, especially artificial food additives, which has become a concern of consumers. There are studies focusing on the impact of food additives on the gut microbiota, as long-term exposure to food additives could induce changes in the microbes, and the gut microbiota is related to human health and disease. Therefore, the aim of this review is to summarize the interaction between the gut microbiota and food additives.

Human matters in asthma: Considering the microbiome in pulmonary health

Microbial communities form an important symbiotic ecosystem within humans and have direct effects on health and well-being. Numerous exogenous factors including airborne triggers, diet, and drugs impact these established, but fragile communities across the human lifespan. Crosstalk between the mucosal microbiota and the immune system as well as the gut-lung axis have direct correlations to immune bias that may promote chronic diseases like asthma. Asthma initiation and pathogenesis are multifaceted and complex with input from genetic, epigenetic, and environmental components. In this review, we summarize and discuss the role of the airway microbiome in asthma, and how the environment, diet and therapeutics impact this low biomass community of microorganisms. We also focus this review on the pediatric and Black populations as high-risk groups requiring special attention, emphasizing that the whole patient must be considered during treatment. Although new culture-independent techniques have been developed and are more accessible to researchers, the exact contribution the airway microbiome makes in asthma pathogenesis is not well understood. Understanding how the airway microbiome, as a living entity in the respiratory tract, participates in lung immunity during the development and progression of asthma may lead to critical new treatments for asthma, including population-targeted interventions, or even more effective administration of currently available therapeutics.

The Effects of Dietary Bacillus amyloliquefaciens TL106 Supplementation, as an Alternative to Antibiotics, on Growth Performance, Intestinal Immunity, Epithelial Barrier Integrity, and Intestinal Microbiota in Broilers

A total of 240 1-day-old Arbor Acres male broilers were randomly divided into five dietary treatments (control feed (CON), supplemented with 75 mg/kg aureomycin (ANT), supplemented with 7.5 × 108 CFU/kg (Ba1) and 2.5 × 109 CFU/kg (Ba1), and 7.5 × 109 CFU/kg (Ba3) Bacillus amyloliquefaciens TL106, respectively) to investigate the probiotic effect of TL106 instead of antibiotics in broilers. On days 1−21, the average daily gain of broilers in the Ba groups was increased compared with the CON group (p < 0.05). In addition, the feed/gain ratio of broilers in the Ba groups was lower than that of broilers in the CON and ANT groups on days 22−42 and days 1−42 (p < 0.05). Compared with the CON group, dietary TL106 increased the digestibility of crude fiber and crude protein (p < 0.05), and the effect was similar to that of the ANT group. The levels of IL-1β, IFN-γ, and IL-6 in serum, jejunum, and ileum of broilers fed TL106 were decreased compared with the control group (p < 0.05). The mRNA expression of tight junction proteins in broilers of ANT and Ba groups was higher than the control group (p < 0.05). After 21 days, villus height and the ratio of villus height to crypt depth of duodenum and jejunum of broilers fed TL106 were higher than the control group (p < 0.05). The concentrations of short-chain fatty acids such as lactate, acetate, propionate, and butyrate in cecal digesta of broilers dietary TL106 were higher than the control group (p < 0.05). The supplementation with TL106 altered the compositions and diversity of the cecal microbiota of broilers. Moreover, supplementation with TL106 improved the ratio of Firmicutes to Bacteroidetes and decreased the relative abundance of Proteobacteria on days 21 and 28, while the abundance of Peptostreptococcaceae, Ruminococcaceae and Lactobacillaceae was increased. On days 35 and 42, broilers fed TL106 had an increased total abundance of Firmicutes and Bacteroidetes and decreased abundances of Lactobacillaceae, while the abundance of Barnesiellaceae was increased. In conclusion, dietary supplementation with TL106 improved the broiler’s growth performance, immune response capacity, gut health, modulated development, and composition of the gut microbiota in broilers. It is suggested that Bacillus amyloliquefaciens TL106 may be a suitable alternative to in-feed antibiotics to improve broiler health and performance.

Unveiling and application of the chicken egg proteome: An overview on a two-decade achievement

Egg proteins are not only the most complete and ideal form of protein for human or embryo nutrition but also play the vital role in the food industry. Egg proteins are subjected to many potential changes under various conditions, which may further alter the nutritional value, physicochemical-properties, and bioactivities of proteins. Recent advances in our understanding of the proteome of raw egg matrix from different species and dynamic changes occurring during storage and incubation are developing rapidly. This review provides a comprehensive overview of the main characteristics of chicken egg proteome, covering all its components and applications under various conditions, such as markers detection, egg quality evaluation, genetic and biological unknown identification, and embryonic nutritional supplementation, which not only contributes to our in-depth understanding of each constituent functionality of proteome, but also provides information to increase the value to egg industry.

Dietary Component-Induced Inflammation and Its Amelioration by Prebiotics, Probiotics, and Synbiotics

A balanced diet with many dietary components maintains immune homeostasis directly by interacting with innate and adaptive immune components or indirectly through gut microbiota and their metabolites. Dietary components may inhibit pro-inflammatory mediators and promote anti-inflammatory functions or vice versa. Western diets with imbalanced dietary components skew the immune balance toward pro-inflammation and induce intestinal inflammation, consequently leading to many intestinal and systemic inflammatory diseases like ulcerative colitis, Crohn's disease, irritable bowel syndrome, cardiovascular problems, obesity, and diabetes. The dietary component-induced inflammation is usually chronic in nature and frequently caused or accompanied by alterations in gut microbiota. Therefore, microbiome-targeted therapies such as probiotics, prebiotics and synbiotics hold great potentials to amend immune dysregulation and gut dysbiosis, preventing and treating intestinal and systemic inflammatory diseases. Probiotics, prebiotics and synbioitcs are progressively being added to foods and beverages, with claims of health benefits. However, the underlining mechanisms of these interventions for preventing and treating dietary component-induced inflammation are still not very clear. In addition, possibly ineffective or negative consequences of some probiotics, prebiotics and synbiotics call for stringent testing and regulation. Here, we will first briefly review inflammation, in terms of its types and the relationship between different dietary components and immune responses. Then, we focus on current knowledge about the direct and indirect effects of probiotics, prebiotics and synbiotics on intestinal and systemic inflammation. Understanding how probiotics, prebiotics and synbiotics modulate the immune system and gut microbiota will improve our strategies for preventing and treating dietary component-induced intestinal inflammation and inflammatory diseases.

Effects of Monascus application on in vitro digestion and fermentation characteristics of fish protein

The aim of this study was to investigate the digestion and fermentation properties of fish protein fermented by Monascus. Semi-dried fish was fermented by applying Monascus purpureus Went M 3.439. Our results show that the Monascus fermentation of the fish protein enriched the free amino acids and achieved a relatively higher glutamate content than the control group. The Monascus treatment promoted the decomposition of the fish protein during in vitro digestion, reduced the ammonia and indole content and tended to increase the propionic acid content during in vitro fermentation. The Monascus treatment considerably changed the gut microbiota composition, and particularly increased the relative abundance of Parabacteroides in the in vitro fermentation model of human distal colon. Consumption of Monascus fermented fish protein could result in positive changes in fermentation metabolites and gut microbiota, which brings potential health benefits.

Effect of Dietary Protein and Processing on Gut Microbiota-A Systematic Review

The effect of diet on the composition of gut microbiota and the consequent impact on disease risk have been of expanding interest. The present review focuses on current insights of changes associated with dietary protein-induced gut microbial populations and examines their potential roles in the metabolism, health, and disease of animals. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol was used, and 29 highly relevant articles were obtained, which included 6 mouse studies, 7 pig studies, 15 rat studies, and 1 in vitro study. Analysis of these studies indicated that several factors, such as protein source, protein content, dietary composition (such as carbohydrate content), glycation of protein, processing factors, and protein oxidation, affect the digestibility and bioavailability of dietary proteins. These factors can influence protein fermentation, absorption, and functional properties in the gut and, consequently, impact the composition of gut microbiota and affect human health. While gut microbiota can release metabolites that can affect host physiology either positively or negatively, the selection of quality of protein and suitable food processing conditions are important to have a positive effect of dietary protein on gut microbiota and human health.

Egg consumption improves vascular and gut microbiota function without increasing inflammatory, metabolic, and oxidative stress markers

Egg consumption is one of the many inconsistencies in evidence linking dietary cholesterol to cardiovascular disease (CVD). In addition, the gut microbiota and its metabolite, trimethylamine-N-oxide (TMAO), have been shown to play a crucial role in the development of CVD. The fact that egg is rich in choline suggests that excessive egg consumption may increase TMAO production by altering the gut microbiota. However, the effects of egg consumption on vascular function and gut microbiota remain unclear. Here, the diet of nine young male subjects was supplemented with two boiled eggs daily for 2 weeks. Changes in vascular function, inflammation, metabolism, oxidative stress, and gut microbiota were examined. We found that egg consumption increased flow-mediated dilation and decreased brachial-ankle pulse wave velocity. Furthermore, egg consumption positively modulated the gut microbiota function but had no effects on the levels of C-reactive protein, glucose, lipid profile, malondialdehyde, superoxide dismutase, or TMAO. The current study provides evidence that egg consumption improves vascular function, which may be related to the alterations seen in the gut microbiota. Therefore, moderate egg consumption may help to improve vascular and intestinal function in individuals at low risk of developing CVD and other metabolic disorders.

Novel microbiota-related gene set enrichment analysis identified osteoporosis associated gut microbiota from autoimmune diseases

INTRODUCTION

Gut microbiota is now considered to be a hidden organ that interacts bidirectionally with cellular responses in numerous organs belonged to the immune, bone, and nervous systems. Here, we aimed to investigate the relationships between gut microbiota and complex diseases by utilizing multiple publicly available genome-wide association.

MATERIALS AND METHODS

We applied a novel microbiota-related gene set enrichment analysis approach to detect the associations between gut microbiota and complex diseases by processing genome-wide association studies (GWASs) data sets of six autoimmune diseases (including celiac disease (CeD), inflammatory bowel diseases (IBD), multiple sclerosis (MS), primary biliary cirrhosis (PBC), type 1 diabetes (T1D) and primary sclerosing cholangitis (PSC)) and osteoporosis (OP).

RESULTS

The family Oxalobacteraceae and genus Candidatus_Soleaferrea were found to be correlated with all of the six autoimmune diseases (FDR adjusted P < 0.05). Moreover, we observed that the six autoimmune diseases except PBC shared 3 overlapping features (including family Peptostreptococcaceae, order Gastranaerophilales and genus Romboutsia). For all of the six autoimmune diseases and BMDs (LS-BMD and TB-BMD), an association signal was observed for genus Candidatus_Soleaferrea (FDR adjusted P < 0.05). Notably, FA / FN-BMD shared the maximum number of overlapping microbial features (e.g., genus Ruminococcaceae_UCG009, Erysipelatoclostridium and Ruminococcaceae_UCG013).

CONCLUSION

Our study found that part of the gut microbiota could be novel regulators of BMDs and autoimmune diseases via the effects of its metabolites and may lead to a better understanding of the role played by gut microbiota in the communication of the microbiota-skeletal/immune-gut axis.

Sea buckthorn (Hippophae rhamnoides L.) fermentation liquid protects against alcoholic liver disease linked to regulation of liver metabolome and the abundance of gut microbiota

BACKGROUND

Alcoholic liver disease (ALD) refers to liver damage caused by long-term heavy drinking, which causes oxidative stress and changes in gut microbiota. In this paper, we investigated the hepatoprotective effect of sea buckthorn fermentation liquid on ALD in mice and the interaction between ALD and gut microbiota using animal experiments and gut microbiota measurements.

RESULTS

We found that the contents of total flavonoids, total triterpenes and related short-chain fatty acids (SCFAs) in sea buckthorn fermentation liquid (SFL) were significantly greater. Liver index, kidney index, spleen index, serum indexes of liver injury - alanine aminotransferase (ALT) and spartate aminotransferase (AST), inflammatory factors in liver tissues - tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), oxidation indexes - malondialdehyde (MDA) and superoxide dismutase (SOD), and lipid metabolism indexes - high-density liptein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), and triglyceride (TG), suggested that SFL significantly ameliorates liver injury caused by alcohol. By measuring gut microbiota in mice feces samples, we found that the high-dose group of SFL reversed the declining trend of the gut microbiota Firmicutes/Bacteroidetes (F/B) ratio caused by alcohol, reducing the number of gram-negative bacteroidetes. Patescibacteria was tightly connected with the indicators of ALD. At the genus level, high-dose SFL significantly downregulated Akkermansia, Turicibacter, Alistipes and Ruminiclostridium, and improved the abundance of beneficial bacteria in Lactobacillus. In addition, Alistipes and Ruminiclostridium was closely connected with the indicators of ALD.

CONCLUSION

Sea buckthorn fermentation liquid protected against alcoholic liver disease and modulated the composition of gut microbiota. © 2020 Society of Chemical Industry.

Cecum microbiota in rats fed soy, milk, meat, fish, and egg proteins with prebiotic oligosaccharides

Diet is considered the most influential factor in modulating the gut microbiota but how dietary protein sources differ in their modulatory effects is not well understood. In this study, soy, meat (mixture of beef and pork), and fish proteins (experiment 1) and soy, milk (casein), and egg proteins (experiment 2) were fed to rats with cellulose (CEL) and raffinose (RAF); the microbiota composition and short-chain fatty acid concentration in the cecum were determined. Egg protein feeding decreased the concentration of acetic acid and the richness and diversity of the cecum microbiota. RAF feeding increased the concentrations of acetic and propionic acids and decreased the richness and diversity of the cecum microbiota. When fed with CEL, the abundance of Ruminococcaceae and Christensenellaceae, Akkermansiaceae and Tannerellaceae, and Erysipelotrichaceae enhanced with soy protein, meat and fish proteins, and egg protein, respectively. The effects of dietary proteins diminished with RAF feeding and the abundance of Bifidobacteriaceae, Erysipelotrichaceae, and Lachnospiraceae increased and that of Ruminococcaceae and Christensenellaceae decreased regardless of the protein source. These results indicate that, although the effect of prebiotics is more robust and distinctive, dietary protein sources may influence the composition and metabolic activities of the gut microbiota. The stimulatory effects of soy, meat, and egg proteins on Christensenellaceae, Akkermansiaceae, and Erysipelotrichaceae deserve further examination to better elucidate the dietary manipulation of the gut microbiota.