The Effect of White Rice and White Bread as Staple Foods on Gut Microbiota and Host Metabolism

Diet Mediate the Impact of Host Habitat on Gut Microbiome and Influence Clinical Indexes by Modulating Gut Microbes and Serum Metabolites

The impact of external factors on the human gut microbiota and how gut microbes contribute to human health is an intriguing question. Here, the gut microbiome of 3,224 individuals (496 with serum metabolome) with 109 variables is studied. Multiple analyses reveal that geographic factors explain the greatest variance of the gut microbiome and the similarity of individuals' gut microbiome is negatively correlated with their geographic distance. Main food components are the most important factors that mediate the impact of host habitats on the gut microbiome. Diet and gut microbes collaboratively contribute to the variation of serum metabolites, and correlate to the increase or decrease of certain clinical indexes. Specifically, systolic blood pressure is lowered by vegetable oil through increasing the abundance of Blautia and reducing the serum level of 1-palmitoyl-2-palmitoleoyl-GPC (16:0/16:1), but it is reduced by fruit intake through increasing the serum level of Blautia improved threonate. Besides, aging-related clinical indexes are also closely correlated with the variation of gut microbes and serum metabolites. In this study, the linkages of geographic locations, diet, the gut microbiome, serum metabolites, and physiological indexes in a Chinese population are characterized. It is proved again that gut microbes and their metabolites are important media for external factors to affect human health.

The Development and Evaluation of a Literature-Based Dietary Index for Gut Microbiota

The aim of the study was to develop and evaluate a novel dietary index for gut microbiota (DI-GM) that captures dietary composition related to gut microbiota profiles. We conducted a literature review of longitudinal studies on the association of diet with gut microbiota in adult populations and extracted those dietary components with evidence of beneficial or unfavorable effects. Dietary recall data from the National Health and Nutrition Examination Survey (NHANES, 2005-2010, n = 3812) were used to compute the DI-GM, and associations with biomarkers of gut microbiota diversity (urinary enterodiol and enterolactone) were examined using linear regression. From a review of 106 articles, 14 foods or nutrients were identified as components of the DI-GM, including fermented dairy, chickpeas, soybean, whole grains, fiber, cranberries, avocados, broccoli, coffee, and green tea as beneficial components, and red meat, processed meat, refined grains, and high-fat diet (≥40% of energy from fat) as unfavorable components. Each component was scored 0 or 1 based on sex-specific median intakes, and scores were summed to develop the overall DI-GM score. In the NHANES, DI-GM scores ranged from 0-13 with a mean of 4.8 (SE = 0.04). Positive associations between DI-GM and urinary enterodiol and enterolactone were observed. The association of the novel DI-GM with markers of gut microbiota diversity demonstrates the potential utility of this index for gut health-related studies.

Diet-microbiota associations in gastrointestinal research: a systematic review

Interactions between diet and gastrointestinal microbiota influence health status and outcomes. Evaluating these relationships requires accurate quantification of dietary variables relevant to microbial metabolism, however current dietary assessment methods focus on dietary components relevant to human digestion only. The aim of this study was to synthesize research on foods and nutrients that influence human gut microbiota and thereby identify knowledge gaps to inform dietary assessment advancements toward better understanding of diet-microbiota interactions. Thirty-eight systematic reviews and 106 primary studies reported on human diet-microbiota associations. Dietary factors altering colonic microbiota included dietary patterns, macronutrients, micronutrients, bioactive compounds, and food additives. Reported diet-microbiota associations were dominated by routinely analyzed nutrients, which are absorbed from the small intestine but analyzed for correlation to stool microbiota. Dietary derived microbiota-relevant nutrients are more challenging to quantify and underrepresented in included studies. This evidence synthesis highlights advancements needed, including opportunities for expansion of food composition databases to include microbiota-relevant data, particularly for human intervention studies. These advances in dietary assessment methodology will facilitate translation of microbiota-specific nutrition therapy to practice.

INTERACTION BETWEEN FOOD PYRAMID AND GUT MICROBIOTA. A NEW NUTRITIONAL APPROACH

The food pyramid is a pre-established nutritional education tool. The integration between the intestinal microbiome, food groups, and SCFA-producing bacteria, which benefit from the ingestion of these foods, has the potential to further improve and innovate healthy eating. The diet-microbiome interaction needs to be incorporated into nutrition science, and the food pyramid might assist in this interaction and nutritional learning. Against this context, this brief communication proposes through the food pyramid, the interactions between the intestinal microbiota, food groups, and SCFAs-producing bacteria.

The role of cereal soluble fiber in the beneficial modulation of glycometabolic gastrointestinal hormones

According to cohort studies, cereal fiber, and whole-grain products might decrease risk for type 2 diabetes (T2DM), inflammatory processes, cancer, and cardiovascular diseases. These associations, mainly affect insoluble, but not soluble cereal fiber. In intervention studies, soluble fiber elicit anti-hyperglycemic and anti-inflammatory short-term effects, partially explained by fermentation to short-chain fatty acids, which acutely counteract insulin resistance and inflammation. ß-glucans lower cholesterol levels and possibly reduce liver fat. Long-term benefits are not yet shown, maybe caused by T2DM heterogeneity, as insulin resistance and fatty liver disease - the glycometabolic points of action of soluble cereal fiber - are not present in every patient. Thus, only some patients might be susceptive to fiber. Also, incretin action in response to fiber could be a relevant factor for variable effects. Thus, this review aims to summarize the current knowledge from human studies on the impact of soluble cereal fiber on glycometabolic gastrointestinal hormones. Effects on GLP-1 appear to be highly contradictory, while these fibers might lower GIP and ghrelin, and increase PYY and CCK. Even though previous results of specific trials support a glycometabolic benefit of soluble fiber, larger acute, and long-term mechanistic studies are needed in order to corroborate the results.

New hope for Parkinson's disease treatment: Targeting gut microbiota

There might be more than 10 million confirmed cases of Parkinson's disease (PD) worldwide by 2040. However, the pathogenesis of PD is still unclear. Host health is closely related to gut microbiota, which are affected by factors such as age, diet, and exercise. Recent studies have found that gut microbiota may play key roles in the progression of a wide range of diseases, including PD. Changes in the abundance of gut bacteria, such as Helicobacter pylori, Enterococcus faecalis, and Desulfovibrio, might be involved in PD pathogenesis or interfere with PD therapy. Gut microbiota and the distal brain achieve action on each other through a gut‐brain axis composed of the nervous system, endocrine system, and immune system. Here, this review focused on the current understanding of the connection between Parkinson's disease and gut microbiota, to provide potential therapeutic targets for PD.

Access to Healthy Wheat and Maize Processed Foods in Mexico City: Comparisons across Socioeconomic Areas and Store Types

The contributions of processed foods to the overweight and obesity problem in Latin America are well known. Engagement with the private and public sectors on possible solutions requires deeper insights into where and how these products are sold and the related implications for diet quality. This article characterizes the diversity of wheat and maize processed foods (WMPFs) available to consumers in Mexico City. Data were gathered across nine product categories at different points of sale (supermarkets, small grocery stores, convenience stores) in high and low socioeconomic (SE) areas. We assessed WMPFs based on Nutri-Score profile, price, and health and nutrition claims. Roughly 17.4% of the WMPFs were considered healthy, of which 62.2% were pastas and breads. Availability of healthy WMPFs was scarce in most stores, particularly in convenience stores Compared to supermarkets in the low SE area, those in the high SE area exhibited greater variety in access to healthy WMPFs across all product categories. In the low SE area, healthy WMPFs were priced 16–69% lower than unhealthy WMPFs across product categories. The extensive variety of unhealthy WMPFs, the limited stock of healthy WMPFs in most retail outlets, and the confusing health and nutrition claims on packaging make it difficult for urban consumers to find and choose healthy WMPFs.

Nutritional Quality of the Most Consumed Varieties of Raw and Cooked Rice in Spain Submitted to an In Vitro Digestion Model

Rice is one of the most consumed staple foods around the world and its trade is highly globalized. Increased environmental pollution generates a large amount of waste that, in many cases, is discarded close to culture fields. Some species are able to bioaccumulate toxic substances, such as metals, that could be transferred to the food chain. The main goal of this study was to evaluate the content of metallic (Al, Cd, Pb, and Cr) and metalloid elements (As) in 14 of the most consumed varieties of rice in Spain and their effects on human health. The samples were cooked, and human digestion was simulated by using a standard in vitro digestion method. Metallic and metalloid element levels were analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), previous called microwave digestion. Both the human health risk index, Hazard Quotient, and Lifetime Cancer Risk did not show toxic values in any case. Rice with a higher non-digestible fraction showed a higher liberation of proteins and a lower glycemic index. There were no significant differences in the concentrations of metallic and metalloid elements in cooked rice or in the digestible fraction in all varieties analysed. However, Al concentrations were higher than other metals in all varieties studied due to its global distribution. No relationship has been observed between the digestibility of rice and the bioaccessibility of each metallic and metalloid element. All of the studied rice varieties are healthy food products and its daily consumption is safe. The regular monitoring of metals and As in rice consumed in Spain may contribute to improvements in the human health risk evaluation.

Effects of an isoenergetic low Glycaemic Index (GI) diet on liver fat accumulation and gut microbiota composition in patients with non-alcoholic fatty liver disease (NAFLD): a study protocol of an efficacy mechanism evaluation

INTRODUCTION

A Low Glycaemic Index (LGI) diet is a proposed lifestyle intervention in non-alcoholic fatty liver diseases (NAFLD) which is designed to reduce circulating blood glucose levels, hepatic glucose influx, insulin resistance and de novo lipogenesis. A significant reduction in liver fat content through following a 1-week LGI diet has been reported in healthy volunteers. Changes in dietary fat and carbohydrates have also been shown to alter gut microbiota composition and lead to hepatic steatosis through the gut-liver axis. There are no available trials examining the effects of an LGI diet on liver fat accumulation in patients with NAFLD; nor has the impact of consuming an LGI diet on gut microbiota composition been studied in this population. The aim of this trial is to investigate the effects of LGI diet consumption on liver fat content and its effects on gut microbiota composition in participants with NAFLD compared with a High Glycaemic Index (HGI) control diet.

METHODS AND ANALYSIS

A 2×2 cross-over randomised mechanistic dietary trial will allocate 16 participants with NAFLD to a 2-week either HGI or LGI diet followed by a 4-week wash-out period and then the LGI or HGI diet, alternative to that followed in the first 2 weeks. Baseline and postintervention (four visits) outcome measures will be collected to assess liver fat content (using MRI/S and controlled attenuation parameter-FibroScan), gut microbiota composition (using 16S RNA analysis) and blood biomarkers including glycaemic, insulinaemic, liver, lipid and haematological profiles, gut hormones levels and short-chain fatty acids.

ETHICS AND DISSEMINATION

Study protocol has been approved by the ethics committees of The University of Nottingham and East Midlands Nottingham-2 Research Ethics Committee (REC reference 19/EM/0291). Data from this trial will be used as part of a Philosophy Doctorate thesis. Publications will be in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04415632.

Chinese gut microbiota and its associations with staple food type, ethnicity, and urbanization

The gut microbiota could affect human health and disease. Although disease-associated microbiota alteration has been extensively investigated in the Chinese population, a nationwide Chinese gut microbiota baseline is still lacking. Here we performed 16 S rRNA gene sequencing on fecal samples from 2678 healthy Chinese individuals, who belonged to eight ethnic groups and resided in 63 counties/cities of 28 provinces. We identified four enterotypes, three of which were enriched for Prevotella, Bacteroides, and Escherichia, respectively, whereas the fourth one had no dominant genus. By assessing the association between the gut microbiota and 20 variables belonging to six categories, geography, demography, diet, urbanization, lifestyle, and sampling month, we revealed that geography explained the largest microbiota variation, and clarified the distinct patterns in the associations with staple food type, ethnicity, and urban/rural residence. Specifically, the gut microbiota of Han Chinese and ethnic minority groups from the same sites was more alike than that of the same ethnic minority groups from different sites. Individuals consuming wheat as staple food were predicted to have more microbial genes involving in glucan 1,3-beta-glucosidase and S-adenosyl-L-methionine biosynthesis than those who consumed rice, based on functional prediction. Besides, an appreciable effect of urbanization on decreased intra-individual diversity, increased inter-individual diversity, and increased proportion of the Bacteroides enterotype was observed. Collectively, our study provided a nationwide gut microbiota baseline of the Chinese population and knowledge on important covariates, which are fundamental to translational microbiota research.

A Polyphenol Enriched Variety of Apple Alters Circulating Immune Cell Gene Expression and Faecal Microbiota Composition in Healthy Adults: A Randomized Controlled Trial

Polyphenols within fruits and vegetables may contribute to health benefits due to their consumption, with the anthocyanin sub-set also adding colour. The Lemonade™ apple variety has green skin and white flesh, with low anthocyanin content, while some apple varieties have high anthocyanin content in both the skin and flesh. Effects of red compared with white-fleshed apples were studied in healthy human subjects in a randomized, placebo-controlled, cross-over intervention trial. Twenty-five healthy subjects consumed dried daily portions of the red-fleshed or placebo (white-fleshed) apple for two weeks, followed by one-week washout and further two-week crossover period. During the study, volunteers provided faecal samples for microbiota composition analysis and blood samples for peripheral blood mononuclear cell (PBMC) gene expression analysis. Subtle differences were observed in the faecal microbiota of subjects that were fed the different apples, with significant (p < 0.05) reductions in relative abundances of Streptococcus, Ruminococcus, Blautia, and Roseburia, and increased relative abundances of Sutterella, Butyricicoccus, and Lactobacillus in subjects after consuming the red apple. Changes in PBMC gene expression showed 18 mRNA transcripts were differentially expressed between the two groups, of which 16 were immunoglobulin related genes. Pathway analysis showed that these genes had roles in pathways such as immunoglobulin production, B cell-mediated immunity, complement activation, and phagocytosis. In conclusion, this study shows that anthocyanin-rich apples may influence immune function compared to control apples, with changes potentially associated with differences in the faecal microbiota.

Gut microbiota composition and functional prediction in diarrhea-predominant irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is common and difficult to treat and its pathogenesis is closely related to gut microbiota. However, differences in gut microbiota of patients in different regions make it more difficult to elucidate the mechanism of IBS. We performed an analysis of gut microbiota composition and functional prediction in Chinese patients with diarrhea-predominant IBS (IBS-D).

METHODS

Fecal samples were obtained from 30 IBS-D patients and 30 healthy controls (HCs) in Nanchang, China. Using 16S gene sequence profiles, we analyzed the abundance of dominant microbiota at different taxonomy levels. Based on 16S information, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was used to predicting the function of gut microbiota.

RESULTS

Compared to HCs, gut microbiota richness but not diversity was decreased in IBS-D patients. The abundant phyla Firmicutes, Fusobacteria and Actinobacteria decreased significantly, and Proteobacteria increased significantly in IBS-D patients. PICRUSt indicated that function expression of gut microbiota in IBS-D patients was up-regulated in metabolism of cofactors and vitamins, xenobiotics biodegradation and metabolism, and down-regulated in environmental adaptation, cell growth and death.

CONCLUSIONS

Compared with the normal population in China, IBS-D patients are characterized by complex and unstable gut microbiota, which may influence inflammation and metabolism of the host.

In silico characterization of the impact of mutation (LEU112PRO) on the structure and function of carotenoid cleavage dioxygenase 8 in Oryza sativa

Mutation (p.LEU112PRO) in "carotenoid cleavage dioxygenase 8" (CCD8) protein increases tiller formation in rice plants by cross-talking with auxin and cytokinins. However, owing to the nonexistence of a "three-dimension" structure of CCD8, detail information about its structure and function remain elusive until date. Hence, in the present study, computational approaches were adopted to predict "three-dimensional" (3D) structure of CCD8 protein through comparative modeling techniques and to study the effect of mutation (p.LEU112PRO) on its function as well as architecture through "molecular dynamics" simulation studies. The obtained result reveals that wild-type CCD8 protein is made up of 10 α-helix and 25 β-strands while mutant CCD8 is made up of 11 α-helix and 24 β-strands. Further, molecular docking studies reveals that the wild-type has a better binding affinity with auxin and cytokinin in comparison to mutant. Subsequent molecular dynamics simulation of these four complexes, separately, reveals that the movement of both wild-type as well as mutant CCD8 get reduced after binding with auxin, which in turn prevent auxin transport out of the bud and increases tiller number. However, when cytokinin binds with wild-type and mutant CCD8, it inhibits and enhance CCD8 activity, respectively. As cytokinin positively regulates tiller number formation, enhance activity of mutant CCD8 after binding with cytokinin might be the main reason for more tiller number in mutant than wild-type plant. In the near future, mutant CCD8 along with auxin and cytokinin may be utilized for increasing grain yield in rice plants.

Environmental risk factors for multiple sclerosis in Japanese people

BACKGROUND

The prevalence of multiple sclerosis (MS) has been increasing worldwide in recent years, especially among females. The same increasing trends are even observed in East Asian countries, where the prevalence of MS is relatively low compared with Northern European ancestries. Whether the environmental risk factors for MS are shared between Asian and North European ancestries, and the types of environmental factors that contribute to the low and recent increase in MS prevalence in Asian countries remain unknown. This study provides the first comprehensive survey of environmental risks for MS in East Asia.

METHODS

Patients with MS were recruited from the Department of Neurology at Kyushu University Hospital, Japan between 01 April 2017 and 31 March 2018. Healthy controls (HCs) were recruited by public notification. All participants were residents of Kyushu Island and were required to complete medical history and lifestyle questionnaires. Dietary data were collected using a Food Frequency Questionnaire comprising intake of approximately 140 food and beverage items in the past 1 year. One hundred and three patients with MS and 124 healthy controls (HCs) completed the questionnaires. Age at onset and disability score measured by the Kurtzke Expanded Disability Status Scale (EDSS) were obtained from medical records.

RESULTS

Frequency of obesity (body mass index ≥25 kg/m²) at present time was higher in MS patients than in HCs (19.4% vs. 7.4%, p = 0.009), while body mass index at age 18-20 years did not differ between the two groups. Frequency of current or ex-smokers was higher in MS patients than in HCs (50.5% vs. 22.8%, p < 0.0001) and disability measured by the EDSS was more severe in MS patients with active smoking history than in patients without such history (p = 0.006 after adjusting for sex). Passive smoking after age 16 years was also a risk factor for MS (odds ratio: 1.31, 95% confidence interval: 1.05-1.63, p = 0.015). Longer sunlight exposure in early childhood was a protective factor for MS (odds ratio: 0.65 during summer and 0.71 during winter at age 6-10 years; 0.71 during summer and 0.72 during winter at age 11-15 years). MS patients had earlier age of menarche than HCs (mean: 12.4 years vs. 12.9 years, p = 0.031). Intake of grains was lower in MS patients than in HCs, with intake of rice in particular being significantly lower in MS patients than in HCs (mean: 235.2 g/day vs. 280.6 g/day, p = 0.006). Previously reported foods associated with MS in Northern European ancestries were not replicated in Japanese people.

CONCLUSION

Smoking and earlier age of menarche are positively associated and sunlight exposure in early childhood is negatively associated with MS in Japanese people as shown in Caucasians. Intake of steamed short-grain white rice, a staple food in Japan, is newly found to be negatively associated with MS in Japanese people. Although the causality is unclear because the participants were prevalent cases, these environmental factors may be involved in the rising prevalence of MS in Japanese females.