Microbiota intestinal e risco cardiometabólico: mecanismos e modulação dietética

Butyrate supplementation in the liquid diet of dairy calves leads to a rapid recovery from diarrhea and reduces its occurrence and relapses in the preweaning period

The present study aimed to evaluate the effect of continuous butyrate administration in dairy calves' liquid diet considering diarrhea, metabolic profile, gastrointestinal development, and corporal growth. Immediately after birth, calves were randomly allocated into 2 groups of 62 calves (50 females and 12 males), with access to water and a solid feed ad libitum. The butyrate group (BG) received 4 g/d of sodium butyrate (Admix Easy, Adisseo) diluted in the whole milk, and the control group (CG) received whole milk with no supplementation. Sodium butyrate was administered from d 1 of life until the weaning at 90 d. Feces consistency was assessed daily for the first 30 d of life and characterized by scores from 0 to 4 (0 and 1 for normal, and 2, 3, and 4 for abnormal feces). Diarrhea was diagnosed when the animals had abnormal feces and fever. Morbidity, recurrence, mortality, and lethality data were recorded and compared between the groups. Average daily gain (ADG) and corporal growth (body weight, thoracic perimeter, height at the withers, and croup width) were evaluated weekly, from the first day to d 30, and later at 45, 60, and 90 d of life. Blood samples were taken weekly for up to 30 d to determine the circulating levels of total calcium, phosphorus, chloride, bicarbonate, glucose, β-hydroxybutyrate, and nonesterified fatty acids. The males were euthanized at 15 (n = 6 per group) and 30 d (n = 6 per group) for morphometric, histological, and gene expression analysis of the gastrointestinal tract. The results showed that the BG had a lower rate of morbidity (BG = 30% vs. CG = 50%) and recurrence (BG = 26.7% vs. CG = 60%) of diarrhea than the CG. In addition, the BG had abnormal feces for a shorter period (BG = 4.64 ± 0.47 d vs. CG = 8.6 ± 0.65 d). The ADG tended to be higher in BG than CG up to 30 and 60 d. Metabolic evaluations showed the lowest levels of glucose and highest levels of nonesterified fatty acids in BG. On d 30 of life, rumen papillae length, papilla area, duodenum villus length, and crypt depth were higher in BG than in CG. The duodenal gene expression at 30 d showed that animals with diarrhea episodes that did not receive butyrate had the highest levels of transcripts for the LCT and GLP2 genes. In addition, in different ways, both butyrate and neonatal diarrhea affected the gene expression of IGF1, SLC5A1, and AQP3. These results allow us to conclude that continuous supplementation with sodium butyrate improves gastrointestinal development, reduces the occurrence of diarrhea, and makes clinical conditions milder with faster recovery, favoring a higher ADG in the first 30 and 60 d of life. Based on these results, we conclude that sodium butyrate can be indicated for liquid diet supplementation to accelerate gastrointestinal tract development and prevent severe cases of neonatal diarrhea, tending to improve average daily gain until weaning.

Synergistic synbiotic containing fructooligosaccharides and Lactobacillus delbrueckii CIDCA 133 alleviates chemotherapy-induced intestinal mucositis in mice

Intestinal mucositis is a commonly reported side effect in oncology patients undergoing chemotherapy and radiotherapy. Probiotics, prebiotics, and synbiotics have been investigated as alternative therapeutic approaches against intestinal mucositis due to their well-known anti-inflammatory properties and health benefits to the host. Previous studies showed that the potential probiotic Lactobacillus delbrueckii CIDCA 133 and the prebiotic Fructooligosaccharides (FOS) alleviated the 5-Fluorouracil (5-FU) chemotherapy-induced intestinal mucosa damage. Based on these previous beneficial effects, this work evaluated the anti-inflammatory property of the synbiotic formulation containing L. delbrueckii CIDCA 133 and FOS in mice intestinal mucosa inflammation induced by 5-FU. This work showed that the synbiotic formulation was able to modulate inflammatory parameters, including reduction of cellular inflammatory infiltration, gene expression downregulation of Tlr2, Nfkb1, and Tnf, and upregulation of the immunoregulatory Il10 cytokine, thus protecting the intestinal mucosa from epithelial damage caused by the 5-FU. The synbiotic also improved the epithelial barrier function by upregulating mRNA transcript levels of the short chain fatty acid (SCFA)-associated GPR43 receptor and the occludin tight junction protein, with the subsequent reduction of paracellular intestinal permeability. The data obtained showed that this synbiotic formulation could be a promising adjuvant treatment to be explored against inflammatory damage caused by 5-FU chemotherapy.

Gut microbiota and gestational Diabetes Mellitus: A systematic review

BACKGROUND

Gestational Diabetes Mellitus (GDM) is one of the most prevalent complications of pregnancy and can cause adverse maternal and fetal outcomes. The maternal gut microbiota is involved in several metabolic functions, but it is not yet known its role in GDM physiopathology. This study aims to review the role of gut microbiota in pregnancies that evolved with GDM.

METHODS

Systematic search of the PubMed, Embase, and Scopus databases was performed to identify articles published until 18th August 2021 involving the assessment of gut microbiota in pregnancy.

RESULTS

A total of 23 articles were selected for this review. Seventeen studies investigated differences in the gut microbiota of healthy and GDM pregnant women and showed differences in alfa and beta diversity. Six prospective studies found that microbiota changes during pregnancy and showed that some particularities in the microbiome in are associated with the risk of GDM.

CONCLUSION

This systematic review showed that there is a relationship between intestinal microbiota and GDM. Gut microbiota could be a biomarker for early detection of GDM and could be considered a potential target for modification to reduce the risk of GDM.

Is There an Exercise-Intensity Threshold Capable of Avoiding the Leaky Gut?

Endurance-sport athletes have a high incidence of gastrointestinal disorders, compromising performance and impacting overall health status. An increase in several proinflammatory cytokines and proteins (LPS, I-FABP, IL-6, IL-1β, TNF-α, IFN-γ, C-reactive protein) has been observed in ultramarathoners and triathlon athletes. One of the most common effects of this type of physical activity is the increase in intestinal permeability, known as leaky gut. The intestinal mucosa's degradation can be identified and analyzed by a series of molecular biomarkers, including the lactulose/rhamnose ratio, occludin and claudin (tight junctions), lipopolysaccharides, and I-FABP. Identifying the molecular mechanisms involved in the induction of leaky gut by physical exercise can assist in the determination of safe exercise thresholds for the preservation of the gastrointestinal tract. It was recently shown that 60 min of vigorous endurance training at 70% of the maximum work capacity led to the characteristic responses of leaky gut. It is believed that other factors may contribute to this effect, such as altitude, environmental temperature, fluid restriction, age and trainability. On the other hand, moderate physical training and dietary interventions such as probiotics and prebiotics can improve intestinal health and gut microbiota composition. This review seeks to discuss the molecular mechanisms involved in the intestinal mucosa's adaptation and response to exercise and discuss the role of the intestinal microbiota in mitigating these effects.

Probiotics supplementation and insulin resistance: a systematic review

BACKGROUND

Research on intestinal microbiota has grown considerably, as well as the interest on probiotics' supplementation effects on metabolism. Considering high prevalence rates of metabolic diseases linked by insulin resistance, we performed a systematic review of existing literature which addressed the role of probiotics in modulating insulin sensitivity in animals and humans.

METHODS

This systematic review was based on PRISMA guidelines. Searches for original articles published in English from 1990 to January 2020 were made in the electronic database of PubMed from the National Library of Medicine, using Medical Subject Headings to identify longitudinal studies conducted in animals and humans which reported effects of probiotics in a variety of insulin resistance parameters.

RESULTS

Overall, results from 27 probiotic interventions (Lactobacillus, Bifidobacterium, Clostridium and Akkermansia) indicated significant beneficial changes in insulin resistance measures in animal studies. Additionally, they improved lipid profile, inflammatory and oxidative markers, short-chain fatty acids production and microbiota composition. In seven clinical trials, samples and designs were heterogeneous. Five showed benefits in insulin resistance parameters and in two others no effect was detected.

CONCLUSION

Available data regarding the effects of certain probiotics do not guarantee sustained amelioration of insulin resistance in humans. Consistent beneficial results for intestinal barrier function, immune system and metabolism were reported in animals may encourage long-term randomized clinical trials in people with obesity and cardiometabolic risk. Whether supplementation with probiotics in combination with medications and/or prebiotics, associated with a healthy lifestyle, will prove useful to attenuate insulin resistance requires further investigation.

Effects of the Association of Periodontitis and Type 1 Diabetes Mellitus Induced on Periodontal Tissues and the Duodenal Mucosa of Wistar Rats

Forty Wistar rats were used: (1) control group (CG); (2) group of periodontal disease (PD); (3) type 1 diabetes mellitus group (T1DM); (4) type 1 diabetes mellitus + periodontal disease group (T1DM + PD). In groups T1DM and T1DM + PD, T1DM induction was performed with the administration of streptozotocin (STZ) 80 mg/kg intraperitoneal body weight. The PD and T1DM + PD groups were submitted to PD induction with ligation. After the experimental phase and euthanasia, histological, radiographic, and morphological analyses were performed. For data analysis, was used the one-way ANOVA and post-test Tukey. The T1DM + PD group had a significantly higher level of fasting blood glucose compared to the other groups. In radiographic and histomorphometric analyses, the T1DM + PD group showed greater alveolar bone loss compared to the control group. The T1DM + PD group showed greater osteoclastic activity compared to the control, T1DM, and PD groups and exhibited an intense inflammatory infiltrate, most of which were PMN, being that the amount of this group of cells (PMN) was significantly greater than the PD group. The heights of the intestinal villi were statistically higher in the PD, T1DM, T1DM + PD groups, compared to the control. Regarding the height of the crypt, only the T1DM and T1DM + PD groups were significantly higher compared to the other groups. Association of diabetes and periodontal inflammation increased the deleterious effects on bone tissue and adverse effect on the permeability of the duodenal mucosa.

Relationship between intestinal microbiota, diet and biological systems: an integrated view

The health-disease process can be influenced by the intestinal microbiota. As this plays a fundamental role in protecting the organism, the importance of studying the composition and diversity of this community becomes increasingly evident. Changes in the composition of the intestinal bacterial community may result in dysbiosis, and this process may contribute to triggering various diseases in all biological systems. This imbalance of intestinal microbiota homeostasis may alter commensal bacteria and the host metabolism, as well as immune function. Dysbiosis also causes an increase in intestinal permeability due to exposure to molecular patterns associated with the pathogen and lipopolysaccharides, leading to a chronic inflammatory process that can result in diseases for all biological systems. In this context, dietary intervention through the use of probiotics, prebiotics and antioxidant foods can be considered a contribution to the modulation of intestinal microbiota. Probiotics have been used to provide up to 10 billion colony forming units, and probiotic foods, Kefir and fermented natural yogurt are also used. Prebiotics, in turn, are found in supplemental formulations of processed foods and in functional foods that are also sources of phenolic compounds, such as flavonoids, antioxidant and anti-inflammatory substances, polyunsaturated fatty acids, vitamins, and minerals. In this review, we will discuss the relationship between an imbalance in the intestinal microbiota with the development of diseases, besides indicating the need for future studies that can establish bacterial parameters for the gastrointestinal tract by modulating the intestinal microbiota, associated with the adoption of healthy habits during all life cycles.

Alterações clínicas, metabólicas e resistência à insulina entre adolescentes

Resumo Objetivo Analisar as alterações clínicas, metabólicas e sua relação com a resistência à insulina entre adolescentes. Métodos Estudo analítico, realizado com 357 adolescentes de escolas públicas estaduais de um município do Nordeste brasileiro. O formulário aplicado continha as variáveis Índice de Massa Corporal, Circunferência da Cintura, Circunferência do Pescoço, Índice de Conicidade, Pressão Arterial Média; Triglicerídeos, Glicemia, High — Density Lipoprotein Coiesteroi, Insulina e Índice Homeostasis Model Assessment, analisadas por medidas descritivas para variáveis quantitativas; e frequências para variáveis qualitativas. Foram realizados testes de associações através do Qui-quadrado e do teste Odds Ratio. Resultados A prevalência de resistência à insulina foi de 33,9%. As médias da circunferência da cintura, circunferência do pescoço, índice de conicidade, pressão arterial sistólica média e pressão arterial diastólica média estiveram elevadas respectivamente em 4,2%; 30%; 10,9%; 4,2% e 14% dos adolescentes. Os níveis de High – Density Lipoprotein colesterol estiveram diminuídos em 30,5% da amostra, ao passo que os triglicerídeos estavam elevados em 18,8%. Não foi identificada alteração na glicemia. Aqueles que apresentaram índice de massa corporal, circunferência da cintura, circunferência do pescoço, índice de conicidade e triglicerídeos com valores alterados possuíam maiores chances de apresentar resistência à insulina (OD: 3,62; 11,54; 3,50; 4,49; 3,05, respectivamente). De maneira oposta, os adolescentes com pressão arterial sistólica média, pressão arterial diastólica média e High — Density Lipoprotein colesterol alterados não apresentaram significância estatística (p<0,05). Conclusão A resistência à insulina está presente entre os adolescentes, com associações positivas e significativas com alterações clínicas e metabólicas.

Bacupari (Garcinia brasiliensis) extract modulates intestinal microbiota and reduces oxidative stress and inflammation in obese rats

The objective of this study was to evaluate the effects of an ethanolic extract of the bark of bacupari (Garcinia brasiliensis - EEB) on the abundance of intestinal microbiota, concentration of short-chain fatty acids (SCFAs), oxidative stress, and inflammation in obese rats fed a high-fat diet (HFD). Male Wistar rats were divided into three groups: an HFD-fed obese control group, a group fed HFD plus EEB (BHFD) at a dose of 300 mg per animal per day (42 mg 7-epiclusianone and 10.76 mg morelloflavone), and a lean control group fed an AIN-93 M diet for 8 weeks. EEB decreased (p < 0.05) the abundance of organisms belonging to the phyla Firmicutes and Proteobacteria, and increased (p < 0.05) the concentration of propionic acid. Liver concentrations of malondialdehyde, nitric oxide, resistin, and p65 nuclear factor-kappa B p65(NF-κB) decreased (p < 0.05), while the expression of heat shock protein (HSP)72 and catalase increased (p < 0.05) with the consumption of EEB. Moreover, computational molecular modeling studies involving molecular docking between the main constituents of EEB, 7-epiclusianone and morelloflavone, and NF-κB suggested its inhibitory activity, thus corroborating the experimental results. The consumption of EEB may therefore be a promising strategy for the beneficial dietary modulation of the intestinal ecosystem, thereby countering oxidative stress and inflammation in obese rats. This activity is attributable to the presence of bioactive compounds that act individually or synergistically in the scavenging of free radicals or in the inflammatory process.

Probiotics in the treatment of chronic kidney disease: a systematic review

Chronic kidney disease (CKD) is a syndrome caused by the progressive reduction of renal function. This study aimed to systematically examine the effects of supplementation with probiotics in the treatment of CKD. Searches were carried out on databases MEDLINE (PubMed), SciELO, Cochrane, and Clinical Trials. Two independent reviewers selected the studies from which data was extracted. The search included papers written in English and Portuguese published in the 2012-2016 period describing randomized clinical trials. Eight of the 82 eligible articles met the inclusion criteria. Sample size ranged from 18 to 101 individuals with CKD. The duration of the included studies varied from four to 24 weeks. Most of the included articles reported positive effects in renal function and decreased levels of urea, blood urea nitrogen, ammonia, plasma p-cresol, p-cresyl sulfate, and indoxyl sulfate.

Contribution of anthocyanin-rich foods in obesity control through gut microbiota interactions

Obesity is characterized by low-grade inflammation and a number of metabolic disorders. Distal gut microbes' content (microbiota) is not yet fully understood but evidence shows that it is influenced by internal and external factors that modulate its composition and function. The evidence that gut microbiota composition can differ between healthy and obese individuals, as well as for those who maintain specific dietary habits, has led to the study of this environmental factor as a key link between the pathophysiology of obesity and gut microbiota. Data obtained about the role of anthocyanins (ACNs) in microbiota may lead to different strategies to manipulate bacterial populations and promote health. Anthocyanins have been identified as modulators of gut microbiota that contribute to obesity control and these bioactive compounds should be considered to have a prebiotic action. This review addresses the relevance of knowledge about the influence of anthocyanins-rich food consumption on microbiota, and their health-promoting potential in the pathophysiology of obesity. © 2017 BioFactors, 43(4):507-516, 2017.

Gut microbiota interactions with the immunomodulatory role of vitamin D in normal individuals

BACKGROUND

Due to immunomodulatory properties, vitamin D status has been implicated in several diseases beyond the skeletal disorders. There is evidence that its deficiency deteriorates the gut barrier favoring translocation of endotoxins into the circulation and systemic inflammation. Few studies investigated whether the relationship between vitamin D status and metabolic disorders would be mediated by the gut microbiota composition.

OBJECTIVE

We examined the association between vitamin D intake and circulating levels of 25(OH)D with gut microbiota composition, inflammatory markers and biochemical profile in healthy individuals.

METHODS

In this cross-sectional analysis, 150 young healthy adults were stratified into tertiles of intake and concentrations of vitamin D and their clinical and inflammatory profiles were compared. The DESeq2 was used for comparisons of microbiota composition and the log2 fold changes (log2FC) represented the comparison against the reference level. The association between 25(OH)D and fecal microbiota (16S rRNA sequencing, V4 region) was tested by multiple linear regression.

RESULTS

Vitamin D intake was associated with its concentration (r=0.220, p=0.008). There were no significant differences in clinical and inflammatory variables across tertiles of intake. However, lipopolysaccharides increased with the reduction of 25(OH)D (p-trend <0.05). Prevotella was more abundant (log2FC 1.67, p<0.01), while Haemophilus and Veillonella were less abundant (log2FC -2.92 and -1.46, p<0.01, respectively) in the subset with the highest vitamin D intake (reference) than that observed in the other subset (first plus second tertiles). PCR (r=-0.170, p=0.039), E-selectin (r=-0.220, p=0.007) and abundances of Coprococcus (r=-0.215, p=0.008) and Bifdobacterium (r=-0.269, p=0.001) were inversely correlated with 25(OH)D. After adjusting for age, sex, season and BMI, 25(OH)D maintained inversely associated with Coprococcus (β=-9.414, p=0.045) and Bifdobacterium (β=-1.881, p=0.051), but significance disappeared following the addition of inflammatory markers in the regression models.

CONCLUSION

The role of vitamin D in the maintenance of immune homeostasis seems to occur in part by interacting with the gut microbiota. The attenuation of association of bacterial genera by inflammatory markers suggests that inflammation participate in part in the relationship between the gut microbiota and vitamin D concentration. Studies with appropriate design are necessary to address hypothesis raised in the current study.

Worse inflammatory profile in omnivores than in vegetarians associates with the gut microbiota composition

AIMS

To describe the abundance of major phyla and some genera in the gut microbiota of individuals according to dietary habits and examine their associations with inflammatory markers, insulin resistance, and cardiovascular risk profile.

METHODS

A total of 268 non-diabetic individuals were stratified into groups of dietary types (strict vegetarians, lacto-ovo-vegetarians, and omnivores). The taxonomic composition and phylogenetic structure of the microbiota were obtained through the analysis of the 16S rRNA gene. Samples were clustered into operational taxonomic units at 97% similarity using GreenGenes 13.5 database. Clinical, biochemical, and circulating inflammatory markers were compared by ANOVA or Kruskal-Wallis test.

RESULTS

The sample (54.2% women, mean age 49.5 years) was composed of 66 strict vegetarians, 102 lacto-ovo-vegetarians and 100 omnivores. Considering the entire sample, the greatest abundant phyla were Firmicutes (40.7 ± 15.9%) and Bacteroidetes (39.5 ± 19.9%), and no difference in abundances was found between individuals with normal and excess weight. Stratifying by dietary types, the proportion of Firmicutes was lower and of Bacteroidetes was higher in strict vegetarians when compared to lacto-ovo-vegetarians and omnivores. At the genus level, strict vegetarians had a higher Prevotella abundance and Prevotella/Bacteroides ratio than the other groups. They also had a lower proportion of Faecalibacterium than lacto-ovo-vegetarians, and both vegetarian groups had higher proportions than did omnivores. Succinivibrio and Halomonas from the Proteobacteria phylum were overrepresented in omnivores. The omnivorous group showed higher values of anthropometric data, insulin, HOMA-IR, and a worse lipid profile. Inflammatory markers exhibited a gradual and significant increase from the vegetarians and lacto-ovo-vegetarians to the omnivorous group.

CONCLUSIONS

There are differences in gut microbiota composition of individuals with distinct dietary habits, who differ according to their inflammatory and metabolic profiles. Based on the findings relative to bacteria abundances and on their recognized actions in the metabolism, we suggest that exposure to animal foods may favor an intestinal environment which could trigger systemic inflammation and insulin resistance-dependent metabolic disorders.

Nutritionists' Health Study cohort: a web-based approach of life events, habits and health outcomes

INTRODUCTION

Non-communicable chronic diseases (NCCDs) represent a burden for public health. Alongside the established cardiometabolic risk factors such as high blood pressure and disorders of glucose and lipid metabolism, living habits and nutritional status at different stages of life are seen as contributors to this scenario. Gut microbiota composition and subclinical inflammation have been pointed out as underlying mechanisms of NCCDs. Studies involving health professionals have brought relevant contributions to the knowledge about risk factors. Technological advances facilitate data collection and analysis for big samples. A web-based survey addressed to collect data from a cohort study, which is able to identify NCCDs risk factors, is highly desirable. The objective of the Brazilian Nutritionists' Health Study (NutriHS) is to gather online information on early life events, daily habits, emergent cardiometabolic risk factors and health outcomes of a specific subset of the Brazilian population.

METHODS AND ANALYSIS

NutriHS, developed at the School of Public Health-University of Sao Paulo, Brazil, is a research initiative that enrols undergraduates of nutrition courses from Brazilian universities and graduated volunteers. A web-based self-administered system was designed to collect health-related data. After fulfilling online questionnaires (socioeconomic, early life events and lifestyle data), participants are invited to a clinical visit for physical examination and laboratory procedures (blood sampling, faeces collection and body composition). At a 3-year interval, they will be invited to repeat similar procedures.

ETHICS AND DISSEMINATION

The NutriHS research protocol was approved by the Institutional Ethics Committee and is providing promising data which contribute to the understanding of pathophysiological links between early life events, body composition, gut microbiota, and inflammatory and metabolic risk profile. The combination of a friendly tool with the innovative purposes of NutriHS offers a remarkable resource for testing hypotheses about mechanisms of nutrition-related diseases and further planning of preventive programmes in public health.