Dietary soybean protein ameliorates high-fat diet-induced obesity by modifying the gut microbiota-dependent biotransformation of bile acids

Targeting Nrf2 by bioactive peptides alleviate inflammation: expanding the role of gut microbiota and metabolites

Inflammation is a complex process that usually refers to the general response of the body to the harmful stimuli of various pathogens, tissue damage, or exogenous pollutants. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that regulates cellular defense against oxidative damage and toxicity by expressing genes related to oxidative stress response and drug detoxification. In addition to its antioxidant properties, Nrf2 is involved in many other important physiological processes, including inflammation and metabolism. Nrf2 can bind the promoters of antioxidant genes and upregulates their expressions, which alleviate oxidation-induced inflammation. Nrf2 has been shown to upregulate heme oxygenase-1 expression, which promotes NF-κB activation and is closely related with inflammation. Nrf2, as a key factor in antioxidant response, is closely related to the expressions of pro-inflammatory factors, NF-κB pathway and cell metabolism. Bioactive peptides come from a wide range of sources and have many biological functions. Increasing evidence indicates that bioactive peptides have potential anti-inflammatory activities. This article summarized the sources, absorption and utilization of bioactive peptides and their role in alleviating inflammation via Nrf2 pathway. Bioactive peptides can also regulate gut microbiota and alter metabolites, which regulates the Nrf2 pathway through novel pathway and supplement the anti-inflammatory mechanisms of bioactive peptides. This review provides a reference for further study on the anti-inflammatory effect of bioactive peptides and the development and utilization of functional foods.

Commercial Production of Highly Rehydrated Soy Protein Powder by the Treatment of Soy Lecithin Modification Combined with Alcalase Hydrolysis

The low rehydration properties of commercial soy protein powder (SPI), a major plant-based food ingredient, have limited the development of plant-based foods. The present study proposes a treatment of soy lecithin modification combined with Alcalase hydrolysis to improve the rehydration of soy protein powder, as well as other processing properties (emulsification, viscosity). The results show that the soy protein-soy lecithin complex powder, which is hydrolyzed for 30 min (SPH-SL-30), has the smallest particle size, the smallest zeta potential, the highest surface hydrophobicity, and a uniform microstructure. In addition, the value of the ratio of the α-helical structure/β-folded structure was the smallest in the SPH-SL-30. After measuring the rehydration properties, emulsification properties, and viscosity, it was found that the SPH-SL-30 has the shortest wetting time of 3.04 min, the shortest dispersion time of 12.29 s, the highest solubility of 93.17%, the highest emulsifying activity of 32.42 m2/g, the highest emulsifying stability of 98.33 min, and the lowest viscosity of 0.98 pa.s. This indicates that the treatment of soy lecithin modification combined with Alcalase hydrolysis destroys the structure of soy protein, changes its physicochemical properties, and improves its functional properties. In this study, soy protein was modified by the treatment of soy lecithin modification combined with Alcalase hydrolysis to improve the processing characteristics of soy protein powders and to provide a theoretical basis for its high-value utilization in the plant-based food field.

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.

Therapeutic application of natural compounds for skeletal muscle-associated metabolic disorders: A review on diabetes perspective

Skeletal muscle (SM) plays a vital role in energy and glucose metabolism by regulating insulin sensitivity, glucose uptake, and blood glucose homeostasis. Impaired SM metabolism is strongly linked to several diseases, particularly type 2 diabetes (T2D). Insulin resistance in SM may result from the impaired activities of insulin receptor tyrosine kinase, insulin receptor substrate 1, phosphoinositide 3-kinase, and AKT pathways. This review briefly discusses SM myogenesis and the critical roles that SM plays in insulin resistance and T2D. The pharmacological targets of T2D which are associated with SM metabolism, such as DPP4, PTB1B, SGLT, PPARγ, and GLP-1R, and their potential modulators/inhibitors, especially natural compounds, are discussed in detail. This review highlights the significance of SM in metabolic disorders and the therapeutic potential of natural compounds in targeting SM-associated T2D targets. It may provide novel insights for the future development of anti-diabetic drug therapies. We believe that scientists working on T2D therapies will benefit from this review by enhancing their knowledge and updating their understanding of the subject.

Bile acid and its bidirectional interactions with gut microbiota: a review

Bile acids (BAs) are an important metabolite produced by cholesterol catabolism. It serves important roles in glucose and lipid metabolism and host-microbe interaction. Recent research has shown that different gut-microbiota can secrete different metabolic-enzymes to mediate the deconjugation, dehydroxylation and epimerization of BAs. In addition, microbes mediate BAs transformation and exert physiological functions in metabolic diseases may have a potentially close relationship with diet. Therefore, elaborating the pathways by which gut microbes mediate the transformation of BAs through enzymatic reactions involved are principal to understand the mechanism of effects between dietary patterns, gut microbes and BAs, and to provide theoretical knowledge for the development of functional foods to regulate metabolic diseases. In the present review, we summarized works on the physiological function of BAs, as well as the classification and composition of BAs in different animal models and its organs. In addition, we mainly focus on the bidirectional interactions of gut microbes with BAs transformation, and discuss the effects of diet on microbial transformation of BAs. Finally, we raised the question of further in-depth investigation of the food-gut microbial-BAs relationship, which might contribute to the improvement of metabolic diseases through dietary interventions in the future.

Extension Region Domain of Soybean 7S Globulin Contributes to Serum Triglyceride-Lowering Effect via Modulation of Bile Acids Homeostasis

SCOPE

Soybean 7S globulin (β-conglycinin), a major soybean storage protein, has been demonstrated to exert remarkable triglyceride (TG) and cholesterol-lowering effects, yet the underlying mechanism remains controversial.

METHODS AND RESULTS

A comparative investigation is performed to assess the contribution of different structural domains of soybean 7S globulin, including core region (CR) and extension region (ER) domains, to biological effects of soybean 7S globulin using a high-fat diet rat model. The results show that ER domain mainly contributes to the serum TG-lowering effect of soybean 7S globulin, but not for CR domain. Metabolomics analysis reveals that oral administration of ER peptides obviously influences the metabolic profiling of serum bile acids (BAs), as well as significantly increased the fecal excretion of total BAs. Meanwhile, ER peptides supplementation reshapes the composition of gut microbiota and impacts the gut microbiota-dependent biotransformation of BAs which indicate by a significantly increased secondary BAs concentration in fecal samples. These results highlight that TG-lowering effects of ER peptides mainly stem from their modulation of BAs homeostasis.

CONCLUSION

Oral administration of ER peptides can effectively lower serum TG level by regulating BAs metabolism. ER peptides have potential to be used as a candidate pharmaceutical for the intervention of dyslipidemia.

Soy and Gastrointestinal Health: A Review

Soybean is the most economically important legume globally, providing a major source of plant protein for millions of people; it offers a high-quality, cost-competitive and versatile base-protein ingredient for plant-based meat alternatives. The health benefits of soybean and its constituents have largely been attributed to the actions of phytoestrogens, which are present at high levels. Additionally, consumption of soy-based foods may also modulate gastrointestinal (GI) health, in particular colorectal cancer risk, via effects on the composition and metabolic activity of the GI microbiome. The aim of this narrative review was to critically evaluate the emerging evidence from clinical trials, observational studies and animal trials relating to the effects of consuming soybeans, soy-based products and the key constituents of soybeans (isoflavones, soy proteins and oligosaccharides) on measures of GI health. Our review suggests that there are consistent favourable changes in measures of GI health for some soy foods, such as fermented rather than unfermented soy milk, and for those individuals with a microbiome that can metabolise equol. However, as consumption of foods containing soy protein isolates and textured soy proteins increases, further clinical evidence is needed to understand whether these foods elicit similar or additional functional effects on GI health.

The Beneficial Effects of Soybean Proteins and Peptides on Chronic Diseases

With lifestyle changes, chronic diseases have become a public health problem worldwide, causing a huge burden on the global economy. Risk factors associated with chronic diseases mainly include abdominal obesity, insulin resistance, hypertension, dyslipidemia, elevated triglycerides, cancer, and other characteristics. Plant-sourced proteins have received more and more attention in the treatment and prevention of chronic diseases in recent years. Soybean is a low-cost, high-quality protein resource that contains 40% protein. Soybean peptides have been widely studied in the regulation of chronic diseases. In this review, the structure, function, absorption, and metabolism of soybean peptides are introduced briefly. The regulatory effects of soybean peptides on a few main chronic diseases were also reviewed, including obesity, diabetes mellitus, cardiovascular diseases (CVD), and cancer. We also addressed the shortcomings of functional research on soybean proteins and peptides in chronic diseases and the possible directions in the future.

Biological tuners to reshape the bile acid pool for therapeutic purposes in non-alcoholic fatty liver disease

Bile acids synthesized within the hepatocytes are transformed by gut microorganisms and reabsorbed into the portal circulation. During their enterohepatic cycling, bile acids act as signaling molecules by interacting with receptors to regulate pathways involved in many physiological processes. The bile acid pool, composed of a variety of bile acid species, has been shown to be altered in diseases, hence contributing to disease pathogenesis. Thus, understanding the changes in bile acid pool size and composition in pathological processes will help to elaborate effective pharmacological treatments. Five crucial steps along the enterohepatic cycle shape the bile acid pool size and composition, offering five possible targets for therapeutic intervention. In this review, we provide an insight on the strategies to modulate the bile acid pool, and then we discuss the potential benefits in non-alcoholic fatty liver disease.

Dietary Combination of Fish Oil and Soy β-Conglycinin Inhibits Fat Accumulation and Reduces Blood Glucose Levels by Altering Gut Microbiome Composition in Diabetic/Obese KK-A y Mice

Dietary fish oil containing n-3 polyunsaturated fatty acids provides health benefits by lowering lipid levels in the liver and serum. β-Conglycinin (βCG) is a major constituent protein in soybean with many physiological effects, such as lowering blood triglyceride levels, preventing obesity and diabetes, and improving hepatic lipid metabolism. However, the combined effects of fish oil and βCG remain unclear. Here, we investigated the effects of a dietary combination of fish oil and βCG on lipid and glucose parameters in diabetic/obese KK-A ^y mice. KK-A ^y mice were divided into three groups: control, fish oil, and fish oil + βCG; these groups were fed a casein-based diet containing 7% (w/w) soybean oil, a casein-based diet containing 2% (w/w) soybean oil and 5% (w/w) fish oil, and a βCG-based diet containing 2% (w/w) soybean oil and 5% (w/w) fish oil, respectively. The effects of the dietary combination of fish oil and βCG on blood biochemical parameters, adipose tissue weight, expression levels of fat- and glucose metabolism-related genes, and cecal microbiome composition were evaluated. The total white adipose tissue weight (p < 0.05), levels of total serum cholesterol (p < 0.01), triglyceride (p < 0.01), and blood glucose (p < 0.05), and expression levels of fatty acid synthesis-related genes (including Fasn (p < 0.05) and Acc (p < 0.05)), and glucose metabolism-related genes (such as Pepck (p < 0.05)) were lower in the fish oil and fish oil + βCG groups than in the control group. Furthermore, the relative abundance of Bacteroidaceae and Coriobacteriaceae differed significantly between the fish oil + βCG and control groups. These findings suggest that dietary intake of fish oil + βCG may prevent obesity and diabetes, alleviate lipid abnormalities, and alter the gut microbiome composition in diabetic/obese KK-A ^y mice. Further research is needed to build on this study to evaluate the health benefits of major components of Japanese food.

The role of the gut microbiota in health and cardiovascular diseases

The gut microbiota is critical to human health, such as digesting nutrients, forming the intestinal epithelial barrier, regulating immune function, producing vitamins and hormones, and producing metabolites to interact with the host. Meanwhile, increasing evidence indicates that the gut microbiota has a strong correlation with the occurrence, progression and treatment of cardiovascular diseases (CVDs). In patients with CVDs and corresponding risk factors, the composition and ratio of gut microbiota have significant differences compared with their healthy counterparts. Therefore, gut microbiota dysbiosis, gut microbiota-generated metabolites, and the related signaling pathway may serve as explanations for some of the mechanisms about the occurrence and development of CVDs. Several studies have also demonstrated that many traditional and latest therapeutic treatments of CVDs are associated with the gut microbiota and its generated metabolites and related signaling pathways. Given that information, we summarized the latest advances in the current research regarding the effect of gut microbiota on health, the main cardiovascular risk factors, and CVDs, highlighted the roles and mechanisms of several metabolites, and introduced corresponding promising treatments for CVDs regarding the gut microbiota. Therefore, this review mainly focuses on exploring the role of gut microbiota related metabolites and their therapeutic potential in CVDs, which may eventually provide better solutions in the development of therapeutic treatment as well as the prevention of CVDs.

Maternal Treatment with Metformin Persistently Ameliorates High-Fat Diet-Induced Metabolic Symptoms and Modulates Gut Microbiota in Rat Offspring

A maternal high-fat (HF) diet has long-term deleterious effect on offspring. This study aims to evaluate whether maternal metformin (MT) treatment ameliorates the adverse effects of maternal HF diet on offspring and the role of gut microbiota in it. Pregnant Sprague-Dawley rats were randomly assigned to a HF diet (60% fat) or a standard chow diet (11.8% fat) group, and part of the HF diet group rats were co-treated with MT via drinking water (300 mg/kg/day), resulting in three groups according to maternal diet and MT treatment during gestation and lactation. All offspring were weaned on a chow diet. A maternal HF diet showed a significant deleterious effect on offspring’s metabolic phenotype and induced colonic inflammation and gut-barrier disruption through the reshaped gut microbiota. The daily oral administration of MT to HF-fed dams during gestation and lactation reversed the dysbiosis of gut microbiota in both dams and adult offspring. The hypothalamic TGR5 expression and plasma bile acids composition in adult male offspring was restored by maternal MT treatment, which could regulate hypothalamic appetite-related peptides expression and alleviate inflammation, thereby improving male offspring’s metabolic phenotype. The present study indicates that targeting the gut–brain axis through the mother may be an effective strategy to control the metabolic phenotype of offspring.

Effects of Dietary Nutrients on Fatty Liver Disease Associated With Metabolic Dysfunction (MAFLD): Based on the Intestinal-Hepatic Axis

Non-alcoholic fatty liver disease (NAFLD) has recently become the most common liver disease with a global prevalence of over 25% and is expected to increase. Recently, experts have reached a consensus that “fatty liver disease associated with metabolic dysfunction or MAFLD” may be a more appropriate and inclusive definition than NAFLD. Like the former name NAFLD, MAFLD, as a manifestation of multiple system metabolic disorders involving the liver, has certain heterogeneity in its pathogenesis, clinical manifestations, pathological changes and natural outcomes. We found that there is a delicate dynamic balance among intestinal microflora, metabolites and host immune system to maintain a healthy intestinal environment and host health. On the contrary, this imbalance is related to diseases such as MAFLD. However, there are no clear studies on how dietary nutrients affect the intestinal environment and participate in the pathogenesis of MAFLD. This review summarizes the interactions among dietary nutrients, intestinal microbiota and MAFLD in an attempt to provide evidence for the use of dietary supplements to regulate liver function in patients with MAFLD. These dietary nutrients influence the development and progression of MAFLD mainly through the hepatic-intestinal axis by altering dietary energy absorption, regulating bile acid metabolism, changing intestinal permeability and producing ethanol. Meanwhile, the nutrients have the ability to combat MAFLD in terms of enriching abundance of intestinal microbiota, reducing Firmicutes/Bacteroidetes ratio and promoting abundance of beneficial gut microbes. Therefore, family therapy with MAFLD using a reasonable diet could be considered.

Evaluation of Hypoglycemic and Antioxidant Activities of Soybean Meal Products Fermented by Lactobacillus plantarum FPS 2520 and Bacillus subtilis N1 in Rats Fed with High-Fat Diet

The hypoglycemic and antioxidant activities of Lactobacillus plantarum FPS 2520 and/or Bacillus subtilis N1 fermented soybean meal (SBM) in rats fed a high-fat diet (HFD) were investigated by assessing plasma glucose levels, insulin resistance, and oxidative stress-induced organ damage. Supplementation with FPS 2520- and/or N1-fermented SBM (500 and 1000 mg/kg of body weight per day) to HFD-induced obese rats for 6 weeks significantly down-regulated the concentration of plasma glucose during the oral glucose tolerance test (OGTT), as well as the concentration of fasting plasma glucose, insulin, and the value of the homeostasis model assessment of insulin resistance (HOMA-IR). In addition, plasma and hepatic levels of malondialdehyde (MDA) were alleviated in rats fed fermented SBM, especially SBM fermented by mixed strains. Moreover, fermented SBM treatment reduced HFD-exacerbated increases in plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and uric acid levels. Based on these results, we clearly demonstrate the effect of fermented SBM on improving insulin resistance and oxidation-induced organ damage. Therefore, it is suggested that fermented SBM has the potential to be developed as functional foods for the management of obesity-induced hyperglycemia and organ damage.

Physiological Role of Bile Acids Modified by the Gut Microbiome

Bile acids (BAs) are produced from cholesterol in the liver and are termed primary BAs. Primary BAs are conjugated with glycine and taurine in the liver and then released into the intestine via the gallbladder. After the deconjugation of glycine or taurine by the gut microbiome, primary BAs are converted into secondary BAs by the gut microbiome through modifications such as dehydroxylation, oxidation, and epimerization. Most BAs in the intestine are reabsorbed and transported to the liver, where both primary and secondary BAs are conjugated with glycine or taurine and rereleased into the intestine. Thus, unconjugated primary Bas, as well as conjugated and unconjugated secondary BAs, have been modified by the gut microbiome. Some of the BAs reabsorbed from the intestine spill into the systemic circulation, where they bind to a variety of nuclear and cell-surface receptors in tissues, whereas some of the BAs are not reabsorbed and bind to receptors in the terminal ileum. BAs play crucial roles in the physiological regulation of various tissues. Furthermore, various factors, such as diet, age, and antibiotics influence BA composition. Here, we review recent findings regarding the physiological roles of BAs modified by the gut microbiome in the metabolic, immune, and nervous systems.

Differences in the gut microbiota composition of rats fed with soybean protein and their derived peptides

Current studies regarding the effect of different nitrogen sources on gut microbiota have thus far disregarded the ability of probiotics and coliforms to compete for protein. This study aimed to investigate the differences in the utilization of soybean protein (SPro) and its derived peptides (SPep) by the gut microbiota of Sprague Dawley (SD) rats. The SPro and SPep prepared in this study showed extensive SPro molecular weight distribution, while that of SPep was minimal, ranging between 150 and 1000 Da and primarily consisting of two to five amino acids. The cecum microflora composition of the rats was determined via 16S rDNA amplicon sequencing, showing that the SPro and SPep significantly increased the abundance and uniformity of the gut microbiota after 35 days of feeding. The Firmicutes/Bacteroidetes (F/B) ratios of the SPep, SPro, and casein groups were 2.49 ± 0.60, 2.98 ± 1.12, and 2.59 ± 0.74, respectively. Although the rats fed with SPro and SPep displayed similar gut microbiome structures, SPep significantly promoted Lactobacillus and Phascolarctobacterium growth. The results showed that SPep significantly increased the diversity of the gut microbiota and elevated the probiotic proportion. PRACTICAL APPLICATION: SPro and SPep are two nutritious and high-quality nitrogen sources. The results showed that SPro and SPep regulated the structure of gut microbiota in rats, and the effect of SPep was better. This study provides a theoretical basis for developing SPep functional foods able to regulate gut microbiota and maintain health.

Curdlan intake changes gut microbial composition, short-chain fatty acid production, and bile acid transformation in mice

Indigestible polysaccharides, such as dietary fibers, benefit the host by improving the intestinal environment. Short-chain fatty acids (SCFAs) produced by gut microbial fermentation from dietary fibers exert various physiological effects. The bacterial polysaccharide curdlan benefits the host intestinal environment, although its effect on energy metabolism and SCFA production remains unclear. Hence, this study aimed to elucidate the effect of curdlan intake on gut microbial profiles, SCFA production, and energy metabolism in a high-fat diet (HFD)-induced obese mouse model. Gut microbial composition of fecal samples from curdlan-supplemented HFD-fed mice indicated an elevated abundance of Bacteroidetes, whereas a reduced abundance of Firmicutes was noted at the phylum level compared with that in cellulose-supplemented HFD-fed mice. Moreover, curdlan supplementation resulted in an abundance of the family Bacteroidales S24-7 and Erysipelotrichaceae, and a reduction in Deferribacteres in the feces. Furthermore, curdlan supplementation elevated fecal SCFA levels, particularly butyrate. Although body weight and fat mass were not affected by curdlan supplementation in HFD-induced obese mice, HFD-induced hyperglycemia was significantly suppressed with an increase in plasma insulin and incretin GLP-1 levels. Curdlan supplementation elevated fecal bile acid and SCFA production, improved host metabolic functions by altering the gut microbial composition in mice.

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Curdlan improves gut microbial composition in high-fat diet-fed (HFD) mice.

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The effects of HFD-induced hyperglycemia are mitigated by curdlan supplementation.

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Curdlan supplementation increases plasma insulin and GLP-1 levels.

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Curdlan increases fecal short-chain fatty acids (SCFAs) and secondary bile acids.

Effect of Soybean and Soybean Koji on Obesity and Dyslipidemia in Rats Fed a High-Fat Diet: A Comparative Study

Soybean koji refers to steamed soybeans inoculated with microbial species. Soybean fermentation improves the health benefits of soybeans. Obesity is a serious health concern owing to its increasing incidence rate and high association with other metabolic diseases. Therefore, we investigated the effects of soybean and soybean koji on high-fat diet-induced obesity in rats. Five-week-old male Sprague-Dawley rats were randomly divided into four groups (n = 8/group) as follows: (1) regular diet (RD), (2) high-fat diet (HFD), (3) HFD + steamed soybean (HFD+SS), and (4) HFD + soybean koji (HFD+SK). SK contained more free amino acids and unsaturated fatty acids than SS. In a rat model of obesity, SK consumption significantly alleviated the increase in weight of white adipose tissue and mRNA expression of lipogenic genes, whereas SS consumption did not. Both SS and SK reduced serum triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels, and increased high-density lipoprotein cholesterol levels. SS and SK also inhibited lipid accumulation in the liver and white adipose tissue and reduced adipocyte size. Although both SS and SK could alleviate HFD-induced dyslipidemia, SK has better anti-obesity effects than SS by regulating lipogenesis. Overall, SK is an excellent functional food that may prevent obesity.

Importance of Intestinal Environment and Cellular Plasticity of Islets in the Development of Postpancreatectomy Diabetes

OBJECTIVE

To elucidate the pathogenesis of postpancreatectomy diabetes mellitus (PPDM).

RESEARCH DESIGN AND METHODS

Forty-eight patients without diabetes undergoing either pancreatoduodenectomy (PD) (n = 20) or distal pancreatectomy (DP) (n = 28) were included. A 75-g oral glucose tolerance test was performed every 6 months. Microbiome composition and short-chain fatty acids (SCFAs) in feces were examined before and 6 months after surgery. The association of histological characteristics of the resected pancreas with PPDM was examined.

RESULTS

During follow-up (median 3.19 years), 2 of 20 PD patients and 16 of 28 DP patients developed PPDM. Proteobacteria relative abundance, plasma glucagon-like peptide 1 (GLP-1), and fecal butyrate levels increased only after PD. Postsurgical butyrate levels were correlated with postsurgical GLP-1 levels. With no significant difference in the volume of the resected pancreas between the surgical procedures, both β-cell and α-cell areas in the resected pancreas were significantly higher in DP patients than in PD patients. In DP patients, the progressors to diabetes showed preexisting insulin resistance compared with nonprogressors, and both increased α- and β-cell areas were predictors of PPDM. Furthermore, in DP patients, α-cell and β-cell areas were associated with ALDH1A3 expression in islets.

CONCLUSIONS

We postulate that a greater removal of β-cells contributes to the development of PPDM after DP. Islet expansion along with preexisting insulin resistance is associated with high cellular plasticity, which may predict the development of PPDM after DP. In contrast, PD is associated with alterations of gut microbiome and increases in SCFA production and GLP-1 secretion, possibly protecting against PPDM development.

Obeticholic acid ameliorates severity of Clostridioides difficile infection in high fat diet-induced obese mice

Severe Clostridiodes difficile infection (CDI) is life-threatening and responds poorly to treatment. Obesity is associated with development of severe CDI. Therefore, to define the mechanisms that exacerbate disease severity, we examined CDI pathogenesis in high-fat diet (HFD)-fed obese mice. Compared to control mice, HFD-fed mice failed to clear C. difficile bacteria which resulted in protracted diarrhea, weight loss and colonic damage. After infection, HFD-induced obese mice had an intestinal bile acid (BA) pool that was dominated by primary BAs which are known promoters of C. difficile spore germination, and lacked secondary BAs that inhibit C. difficile growth. Concurrently, synthesis of primary BAs from liver was significantly increased in C. difficile-infected HFD-fed mice. A key pathway that regulates hepatic BA synthesis is via feedback inhibition from intestinal Farnesoid X receptors (FXRs). Our data reveal that the proportion of FXR agonist BAs to FXR antagonist BAs in the intestinal lumen was significantly reduced in HFD-fed mice after CDI. Treatment of HFD-fed mice with an FXR agonist Obeticholic acid, resulted in decreased primary BA synthesis, fewer C. difficile bacteria and better CDI outcomes. Thus, OCA treatment holds promise as a therapy for severe CDI.

Impact of the factors shaping gut microbiota on obesity

Obesity is considered as a risk factor for chronic health diseases such as heart diseases, cancer and diabetes 2. Reduced physical activities, lifestyle, poor nutritional diet and genetics are among the risk factors associated with the development of obesity. In recent years, several studies have explored the link between the gut microbiome and the progression of diseases including obesity, with the shift in microbiome abundance and composition being the main focus. The alteration of gut microbiome composition affects both nutrients metabolism and specific gene expressions, thereby disturbing body physiology. Specifically, the abundance of fibre-metabolizing microbes is associated with weight loss and that of protein and fat-metabolizing bacteria with weight gain. Various internal and external factors such as genetics, maternal obesity, mode of delivery, breastfeeding, nutrition, antibiotic use and the chemical compounds present in the environment are known to interfere with the richness of the gut microbiota (GM), thus influencing weight gain/loss and ultimately the development of obesity. However, the effectiveness of each factor in potentiating the shift in microbes' abundance to result in significant changes that can lead to obesity is not yet clear. In this review, we will highlight the factors involved in shaping GM, their influence on obesity and possible interventions. Understanding the influence of these factors on the diversity of the GM and how to improve their effectiveness on disease conditions could be keys in the treatment of metabolic diseases.

Coarse Cereals and Legume Grains Exert Beneficial Effects through Their Interaction with Gut Microbiota: A Review

Coarse cereals and legume grains (CCLGs) are rich in specific macro- and functional elements that are considered important dietary components for maintaining human health. Therefore, determining the precise nutritional mechanism involved in exerting the health benefits of CCLGs can help understand dietary nutrition in a better manner. Evidence suggests that gut microbiota play a crucial role in the function of CCLGs via their complicated interplay with CCLGs. First, CCLGs modulate gut microbiota and function. Second, gut microbiota convert CCLGs into compounds that perform different functions. Third, gut microbiota mediate interactions among different CCLG components. Therefore, using gut microbiota to expound the nutritional mechanism of CCLGs is important for future studies. A precise and rapid gut microbiota research model is required to screen and evaluate the quality of CCLGs. The outcomes of such research may promote the rapid discovery, classification, and evaluation of CCLG resources, thereby opening a new opportunity to guide nutrition-based development of CCLG products.

Diabetes downregulates peptide transporter 1 in the rat jejunum: possible involvement of cholate-induced FXR activation

Peptide transporter 1 (PepT1), highly expressed on the apical membrane of enterocytes, is involved in energy balance and mediates intestinal absorption of peptidomimetic drugs. In this study, we investigated whether and how diabetes affected the function and expression of intestinal PepT1. Diabetes was induced in rats by combination of high-fat diet and low dose streptozocin injection. Pharmacokinetics study demonstrated that diabetes significantly decreased plasma exposures of cephalexin and acyclovir following oral administration of cephalexin and valacyclovir, respectively. Single-pass intestinal perfusion analysis showed that diabetes remarkably decreased cephalexin absorption, which was associated with decreased expression of intestinal PepT1 protein. We assessed the levels of bile acids in intestine of diabetic rats, and found that diabetic rats exhibited significantly higher levels of chenodeoxycholic acid (CDCA), cholic acid (CA) and glycocholic acid (GCA), and lower levels of lithocholic acid (LCA) and hyodeoxycholic acid (HDCA) than control rats; intestinal deoxycholic acid (DCA) levels were unaltered. In Caco-2 cells, the 6 bile acids remarkably decreased expression of PepT1 protein with CDCA causing the strongest inhibition, whereas TNF-α, LPS and insulin little affected expression of PepT1 protein; short-chain fatty acids induced rather than decreased expression of PepT1 protein. Farnesoid X receptor (FXR) inhibitor glycine-β-muricholic acid or FXR knockdown reversed the downregulation of PepT1 expression by CDCA and GW4064 (another FXR agonist). In diabetic rats, the expression of intestinal FXR protein was markedly increased. Oral administration of CDCA (90, 180 mg·kg^-1·d^-1, for 3 weeks) dose-dependently decreased the expression and function of intestinal PepT1 in rats. In conclusion, diabetes impairs the expression and function of intestinal PepT1 partly via CDCA-mediated FXR activation.

The Gut Microbiome and Individual-Specific Responses to Diet

Nutritional content and timing are increasingly appreciated to constitute important human variables collectively impacting all aspects of human physiology and disease. However, person-specific mechanisms driving nutritional impacts on the human host remain incompletely understood, while current dietary recommendations remain empirical and nonpersonalized. Precision nutrition aims to harness individualized bodies of data, including the human gut microbiome, in predicting person-specific physiological responses (such as glycemic responses) to food. With these advances notwithstanding, many unknowns remain, including the long-term efficacy of such interventions in delaying or reversing human metabolic disease, mechanisms driving these dietary effects, and the extent of the contribution of the gut microbiome to these processes. We summarize these conceptual advances, while highlighting challenges and means of addressing them in the next decade of study of precision medicine, toward generation of insights that may help to evolve precision nutrition as an effective future tool in a variety of "multifactorial" human disorders.

Molecular Physiology of Bile Acid Signaling in Health, Disease, and Aging

Over the past two decades, bile acids (BAs) have become established as important signaling molecules that enable fine-tuned inter-tissue communication from the liver, their site of production, over the intestine, where they are modified by the gut microbiota, to virtually any organ, where they exert their pleiotropic physiological effects. The chemical variety of BAs, to a large extent determined by the gut microbiome, also allows for a complex fine-tuning of adaptive responses in our body. This review provides an overview of the mechanisms by which BA receptors coordinate several aspects of physiology and highlights new therapeutic strategies for diseases underlying pathological BA signaling.

Antibiotic Treatment Reduces the Health Benefits of Soy Protein

SCOPE

Soy protein is a high-quality protein and its consumption has been associated with a reduction of serum cholesterol and triglycerides and an improvement in insulin resistance. However, it is not known whether the effects of soy protein are mediated by the gut microbiota. Thus, the aim of this study is to assess whether using antibiotics to partially eradicate the gut microbiota can prevent the beneficial effects of soy protein in rats.

METHODS AND RESULTS

Thus, rats are fed one of the following diets for 16 weeks: casein control, soy protein control, high-fat casein, and high-fat soy protein. The rats are then treated for 4 weeks with antibiotics. Body weight and composition, energy expenditure, glucose tolerance test, metabolic endotoxemia, and gut microbiota are measured before and after treatment with antibiotic. The results show that soy protein consumption decreases weight gain, body fat, metabolic endotoxemia, and increases energy expenditure and glucose tolerance. Antibiotic treatment suppresses all these metabolic effects. These changes are accompanied by modifying the diversity and taxonomy of the gut microbiota.

CONCLUSION

In conclusion, the evidence suggests that the health benefits of soy protein are partly dependent of the gut microbiota.

Implications of gut microbiome on coronary artery disease

Despite the enormous progress achieved in diagnosis and medical therapy of coronary artery disease (CAD) in the last decades, CAD continues to represent the leading cause of morbidity and mortality worldwide, leading to a massive health-care cost and social burden. Due to the dynamic and complex nature of CAD, the mechanisms underlying the progression of atherosclerotic plaque were largely unknown. With the development of metagenomics and bioinformatics, humans are gradually understanding the important role of the gut microbiome on their hosts. Trillions of microbes colonize in the human gut, they digest and absorb nutrients, as well as participate in a series of human functions and regulate the pathogenesis of diseases, including the cardiovascular disease (CVD) that has received much attention. Meanwhile, metabolomics studies have revealed associations between gut microbiota-derived metabolic bioactive signaling modules, including trimethylamine-N-oxide (TMAO), short-chain fatty acids (SCFAs), and bile acids (BAs), with the progression of CAD. Disturbance of the gut microbiome and microbial metabolites are important factors leading to CAD, which has become a novel target for CAD prevention and treatment. This review provides a brief overview of gut microbiome composition in CAD patients according to the recently reported studies, summarizes the underlying mechanisms, and highlights the prognostic value of the gut microbiome in CAD.

Nutrition and Gastrointestinal Microbiota, Microbial-Derived Secondary Bile Acids, and Cardiovascular Disease

PURPOSE OF REVIEW

The goal is to review the connection between gut microbiota and cardiovascular disease, with specific emphasis on bile acids, and the influence of diet in modulating this relationship.

RECENT FINDINGS

Bile acids exert a much broader range of biological functions than initially recognized, including regulation of cardiovascular function through direct and indirect mechanisms. There is a bi-directional relationship between gut microbiota modulation of bile acid-signaling properties, and their effects on gut microbiota composition. Evidence, primarily from rodent models and limited human trials, suggest that dietary modulation of the gut microbiome significantly impacts bile acid metabolism and subsequently host physiological response(s). Available evidence suggests that the link between diet, gut microbiota, and CVD risk is potentially mediated via bile acid effects on diverse metabolic pathways. However, further studies are needed to confirm/expand and translate these findings in a clinical setting.

Evaluation of Antiobesity Activity of Soybean Meal Products Fermented by Lactobacillus plantarum FPS 2520 and Bacillus subtilis N1 in Rats Fed with High-Fat Diet

Single strain or mixed strains of Lactobacillus plantarum FPS 2520 and Bacillus subtilis N1 were used to ferment soybean meal (SBM), and the antiobesity activity of the fermented SBM product was investigated in rats fed with high-fat diet (HFD). After fermentation, free amino nitrogen, total peptide, and isoflavone contents were markedly raised, and genistein and daidzein were the major isoflavones in the fermented SBM. After fed with HFD for 10 weeks, obese Sprague-Dawley rats were orally treated with various fermented products for 6 weeks. The body weight gains, as well as weights of abdominal fat and epididymis fat, of rats fed with fermented SBM products were significantly downregulated. The treatment with the mixed-strains fermented SBM product significantly decreased plasma levels of triglyceride (TG), total cholesterol (TC), and low-density lipoprotein-cholesterol, but increased the level of high-density lipoprotein-cholesterol. Moreover, the levels of TG, TC, fatty acid synthase, and acetyl-CoA carboxylase (ACC) in liver were diminished, and the activities of hormone-sensitive lipase and lipoprotein lipase in adipose tissue were augmented. Taken together, these data demonstrated the antiobesity activity of fermented SBM products, among which the product fermented by the mixed strains being the most effective one. Therefore, these fermented SBM products are potential to be developed as functional foods or additives for treatment of obesity and prevention against obesity-induced complications.

Synthetic dietary inulin, Fuji FF, delays development of diet-induced obesity by improving gut microbiota profiles and increasing short-chain fatty acid production

Background

Dietary fiber, including inulin, promotes health via fermentation products, such as short-chain fatty acids (SCFAs), produced from the fiber by gut microbiota. SCFAs exert positive physiological effects on energy metabolism, gut immunity, and the nervous system. Most of the commercial inulin is extracted from plant sources such as chicory roots, but it can also be enzymatically synthesized from sucrose using inulin producing enzymes. Studies conducted on rodents fed with a cafeteria diet have suggested that while increasing plasma propionic acid, synthetic inulin modulates glucose and lipid metabolism in the same manner as natural inulin. Therefore, this study aimed to determine the effects of a synthetic inulin, Fuji FF, on energy metabolism, fecal SCFA production, and microbiota profiles in mice fed with a high-fat/high-sucrose diet.

Methods

Three-week-old male C57BL/6J mice were fed a high-fat/high-sucrose diet containing cellulose or Fuji FF for 12 weeks, and the effects on energy metabolism, SCFA production, and microbiota profiles were evaluated.

Results

Body weight gain was inhibited by Fuji FF supplementation in high-fat/high-sucrose diet-fed C57BL/6J mice by reducing white adipose tissue weight while increasing energy expenditure, compared with the mice supplemented with cellulose. Fuji FF also elevated levels of acetic, propionic and butyric acids in mouse feces and increased plasma propionic acid levels in mice. Moreover, 16S rRNA gene amplicon sequencing of fecal samples revealed an elevated abundance of Bacteroidetes and a reduced abundance of Firmicutes at the phylum level in mice supplemented with Fuji FF compared to those supplemented with cellulose. Fuji FF also resulted in abundance of the family Bacteroidales S24-7 and reduction of Desulfovibrionaceae in the feces.

Conclusion

Long term consumption of Fuji FF improved the gut environment in mice by altering the composition of the microbiota and increasing SCFA production, which might be associated with its anti-obesity effects.

The Timing Effects of Soy Protein Intake on Mice Gut Microbiota

Soy protein intake is known to cause microbiota changes. While there are some reports about the effect of soy protein intake on gut microbiota and lipid metabolism, effective timing of soy protein intake has not been investigated. In this study, we examined the effect of soy protein intake timing on microbiota. Mice were fed twice a day, in the morning and evening, to compare the effect of soy protein intake in the morning with that in the evening. Mice were divided into three groups: mice fed only casein protein, mice fed soy protein in the morning, and mice fed soy protein in the evening under high-fat diet conditions. They were kept under the experimental condition for two weeks and were sacrificed afterward. We measured cecal pH and collected cecal contents and feces. Short-chain fatty acids (SCFAs) from cecal contents were measured by gas chromatography. The microbiota was analyzed by sequencing 16S rRNA genes from feces. Soy protein intake whether in the morning or evening led to a greater microbiota diversity and a decrease in cecal pH resulting from SCFA production compared to casein intake. In addition, these effects were relatively stronger by morning soy protein intake. Therefore, soy protein intake in the morning may have relatively stronger effects on microbiota than that in the evening.

Dietary short-chain fatty acid intake improves the hepatic metabolic condition via FFAR3

Fermented foods represent a significant portion of human diets with several beneficial effects. Foods produced by bacterial fermentation are enriched in short-chain fatty acids (SCFAs), which are functional products of dietary fibers via gut microbial fermentation. In addition to energy sources, SCFAs also act as signaling molecules via G-protein coupled receptors such as FFAR2 and FFAR3. Hence, dietary SCFAs in fermented foods may have a direct influence on metabolic functions. However, the detailed mechanism by dietary SCFAs remains unclear. Here, we show that dietary SCFAs protected against high-fat diet-induced obesity in mice in parallel with increased plasma SCFAs without changing cecal SCFA or gut microbial composition. Dietary SCFAs suppressed hepatic weight and lipid synthesis. These effects were abolished in FFAR3-deficient mice but not FFAR2-deficient. Thus, SCFAs supplementation improved hepatic metabolic functions via FFAR3 without influencing intestinal environment. These findings could help to promote the development of functional foods using SCFAs.

Effect of different sources of dietary protein on muscle hypertrophy in functionally overloaded mice

Dietary protein intake is important for skeletal muscle protein synthesis. In this study, we investigated the differential effect of protein sources on hypertrophy of plantaris muscle induced by surgical ablation of gastrocnemius and soleus muscles. Six-week old mice were fed diets containing caseinate, whey, or soy as protein sources for 2 weeks. Plantaris muscle hypertrophy was induced by a unilateral ablation of synergistic muscles after a week. Food intake of soy protein-fed mice was higher than that of caseinate and whey-fed mice, resulting in higher body and fat weights. Plantaris muscle weight in sham-operated mice was not different across the groups. Overload-operated plantaris muscle weight and increased ratio of overloaded muscle to sham-operated muscle weights were higher in caseinate-fed mice than in whey- and soy protein-fed mice, suggesting caseinate as a promising protein source for muscle hypertrophy.

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Type of dietary protein source affects functionally overloaded muscle hypertrophy.

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Caseinate intake induces higher muscle hypertrophy compared to whey and soy protein.

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Dietary protein sources have no effect on non-overloaded muscle weight.

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There is no effect of dietary protein sources on locomotor activity.

A Network Involving Gut Microbiota, Circulating Bile Acids, and Hepatic Metabolism Genes That Protects Against Non-Alcoholic Fatty Liver Disease

SCOPE

Gut microbiota contributes to non-alcoholic fatty liver disease (NAFLD) pathogenesis by multiple mechanisms not yet completely understood. Novel differential features between germ-free mice (GFm) transplanted with protective or non-protective cecal microbiota against NAFLD are investigated.

METHODS AND RESULTS

Gut microbiota composition, plasma, and fecal bile acids (BAs) and liver mRNAs are quantified in GFm recipients from four donor mice differing in NAFLD severity (control diet, high-fat diet [HFD]-responder, HFD-non-responder, and quercetin-supplemented HFD). Transplanted GFm are on control or HFD for 16-weeks. Multivariate analysis shows that GFm colonized with microbiota from HFD-non-responder and quercetin supplemented-HFD donors (protected against NAFLD) clusters together, whereas GFm colonized with microbiota from control and HFD-responder mice (non-protected against NAFLD) establishes another cluster. Protected phenotype is associated with increased gut Desulfovibrio and Oscillospira, reduced gut Bacteroides and Oribacterium, lower primary and higher secondary BAs in plasma and feces, induction of hepatic BA transporters, and repression of hepatic lipogenic and BA synthesis genes.

CONCLUSION

Protective gut microbiota associates with increased specific secondary BAs, which likely inhibit lipogenic pathways and enhance bile flow in the liver. This novel cross-talk between gut and liver, via plasma BAs, that promotes protection against NAFLD may have clinical and nutritional relevance.

Metagenomic analysis of bile salt biotransformation in the human gut microbiome

BACKGROUND

In the biochemical milieu of human colon, bile acids act as signaling mediators between the host and its gut microbiota. Biotransformation of primary to secondary bile acids have been known to be involved in the immune regulation of human physiology. Several 16S amplicon-based studies with inflammatory bowel disease (IBD) subjects were found to have an association with the level of fecal bile acids. However, a detailed investigation of all the bile salt biotransformation genes in the gut microbiome of healthy and IBD subjects has not been performed.

RESULTS

Here, we report a comprehensive analysis of the bile salt biotransformation genes and their distribution at the phyla level. Based on the analysis of shotgun metagenomes, we found that the IBD subjects harbored a significantly lower abundance of these genes compared to the healthy controls. Majority of these genes originated from Firmicutes in comparison to other phyla. From metabolomics data, we found that the IBD subjects were measured with a significantly low level of secondary bile acids and high levels of primary bile acids compared to that of the healthy controls.

CONCLUSIONS

Our bioinformatics-driven approach of identifying bile salt biotransformation genes predicts the bile salt biotransformation potential in the gut microbiota of IBD subjects. The functional level of dysbiosis likely contributes to the variation in the bile acid pool. This study sets the stage to envisage potential solutions to modulate the gut microbiome with the objective to restore the bile acid pool in the gut.

Fecal Microbial Transplantation and Its Potential Application in Cardiometabolic Syndrome

Newly revealed links between inflammation, obesity, and cardiometabolic syndrome have created opportunities to try previously unexplored therapeutic modalities in these common and life-risking disorders. One potential modulator of these complex disorders is the gut microbiome, which was described in recent years to be altered in patients suffering from features of cardiometabolic syndrome and to transmit cardiometabolic phenotypes upon transfer into germ-free mice. As a result, there is great interest in developing new modalities targeting the altered commensal bacteria as a means of treatment for cardiometabolic syndrome. Fecal microbiota transplantation (FMT) is one such modality in which a disease-associated microbiome is replaced by a healthy microbiome configuration. So far clinical use of FMT has been overwhelmingly successful in recurrent Clostridium difficile infection and is being extensively studied in other microbiome-associated pathologies such as cardiometabolic syndrome. This review will focus on the rationale, promises and challenges in FMT utilization in human disease. In particular, it will overview the role of the gut microbiota in cardiometabolic syndrome and the rationale, experience, and prospects of utilizing FMT treatment as a potential preventive and curative treatment of metabolic human disease.

Precision Nutrition and the Microbiome, Part I: Current State of the Science

The gut microbiota is a highly complex community which evolves and adapts to its host over a lifetime. It has been described as a virtual organ owing to the myriad of functions it performs, including the production of bioactive metabolites, regulation of immunity, energy homeostasis and protection against pathogens. These activities are dependent on the quantity and quality of the microbiota alongside its metabolic potential, which are dictated by a number of factors, including diet and host genetics. In this regard, the gut microbiome is malleable and varies significantly from host to host. These two features render the gut microbiome a candidate ‘organ’ for the possibility of precision microbiomics—the use of the gut microbiome as a biomarker to predict responsiveness to specific dietary constituents to generate precision diets and interventions for optimal health. With this in mind, this two-part review investigates the current state of the science in terms of the influence of diet and specific dietary components on the gut microbiota and subsequent consequences for health status, along with opportunities to modulate the microbiota for improved health and the potential of the microbiome as a biomarker to predict responsiveness to dietary components. In particular, in Part I, we examine the development of the microbiota from birth and its role in health. We investigate the consequences of poor-quality diet in relation to infection and inflammation and discuss diet-derived microbial metabolites which negatively impact health. We look at the role of diet in shaping the microbiome and the influence of specific dietary components, namely protein, fat and carbohydrates, on gut microbiota composition.

Modulation of Gut Microbiota by Soybean 7S Globulin Peptide That Involved Lipopolysaccharide-Peptide Interaction

Soybean protein exhibits nutritional significance for the control of metabolic syndrome, and evidence suggests that gut microbiota are implicated in the control of metabolic disorders. This study aimed to investigate the modulation of pepsin-released peptides of soybean 7S globulin on gut microbiota and possible association between changes of gut microbiota composition and lipopolysaccharide (LPS)-peptide interaction. In vitro fermentation experiments showed that the extension region (ER) fragments of soybean 7S globulin selectively suppressed proinflammatory Gram-negative bacteria. ER peptides also promoted the highest production of short-chain fatty acids (SCFAs), which were associated with increase of the relative abundance of Lachnospiraceae and Lactobacillaceae. Isothermal titration calorimetry (ITC) and Langmuir monolayer studies demonstrated that ER peptides exhibited high affinity to LPS in the presence of Ca²⁺ and developed into β-sheet-rich aggregate structures, thus weakening the stability of LPS monolayers. This finding supplies a possible explanation for improvement of the effects of soybean 7S globulin on metabolic disease.

The role of intestinal microbiota in cardiovascular disease

Accumulating evidence has indicated that intestinal microbiota is involved in the development of various human diseases, including cardiovascular diseases (CVDs). In the recent years, both human and animal experiments have revealed that alterations in the composition and function of intestinal flora, recognized as gut microflora dysbiosis, can accelerate the progression of CVDs. Moreover, intestinal flora metabolizes the diet ingested by the host into a series of metabolites, including trimethylamine N-oxide, short chain fatty acids, secondary bile acid and indoxyl sulfate, which affects the host physiological processes by activation of numerous signalling pathways. The aim of this review was to summarize the role of gut microbiota in the pathogenesis of CVDs, including coronary artery disease, hypertension and heart failure, which may provide valuable insights into potential therapeutic strategies for CVD that involve interfering with the composition, function and metabolites of the intestinal flora.

Dietary Effects on Microbiota-New Trends with Gluten-Free or Paleo Diet

A well-balanced diet is the basis for a healthy life. Both the western diet and special diets can have a relevant impact on the microbiome and promote the development of various diseases. There has been an increase in food-related disorders in recent years, largely associated with dramatic changes in food consumption trends and main nutrients. A major response to food intolerances has been the adoption of new dietary trends involving the reduction or exclusion of specific food ingredients. Especially gluten-containing, but also gluten-free cereals are in the cross-fire. Supporters of the gluten-free diet argue that gluten triggers inflammation and related diseases, while followers of the Paleo diet drastically impeach all cereals as dangerous for human health. To date, no controlled studies support or reject a positive health effect of a gluten-free or cereal-free diet. Future large-scale studies need to evaluate the effect of gluten-containing and gluten-free cereals and the various diets on human health, inflammatory parameters, clinical symptoms, and the gut microbiota (including the bacteria, fungi, and viruses). Dietary-associated changes in compositional and functional microbiota traits should be correlated with the health status for the future development of dietary recommendations and potential clinical interventions.