Background: Recent insights into the role of the human microbiota in cognitive and affective functioning have led to the hypothesis that probiotic supplementation may act as an adjuvant strategy to ameliorate or prevent depression. Objective: Heightened cognitive reactivity to normal, transient changes in sad mood is an established marker of vulnerability to depression and is considered an important target for interventions. The present study aimed to test if a multispecies probiotic containing Bifidobacterium bifidum W23, Bifidobacterium lactis W52, Lactobacillus acidophilus W37, Lactobacillus brevis W63, Lactobacillus casei W56, Lactobacillus salivarius W24, and Lactococcus lactis (W19 and W58) may reduce cognitive reactivity in non-depressed individuals. Design: In a triple-blind, placebo-controlled, randomized, pre- and post-intervention assessment design, 20 healthy participants without current mood disorder received a 4-week probiotic food-supplement intervention with the multispecies probiotics, while 20 control participants received an inert placebo for the same period. In the pre- and post-intervention assessment, cognitive reactivity to sad mood was assessed using the revised Leiden index of depression sensitivity scale. Results: Compared to participants who received the placebo intervention, participants who received the 4-week multispecies probiotics intervention showed a significantly reduced overall cognitive reactivity to sad mood, which was largely accounted for by reduced rumination and aggressive thoughts. Conclusion: These results provide the first evidence that the intake of probiotics may help reduce negative thoughts associated with sad mood. Probiotics supplementation warrants further research as a potential preventive strategy for depression.

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A randomized controlled trial to test the effect of multispecies probiotics on cognitive reactivity to sad mood.

Low-grade inflammation is the hallmark of metabolic disorders such as obesity, type 2 diabetes and nonalcoholic fatty liver disease. Emerging evidence indicates that these disorders are characterized by alterations in the intestinal microbiota composition and its metabolites, which translocate from the gut across a disrupted intestinal barrier to affect various metabolic organs, such as the liver and adipose tissue, thereby contributing to metabolic inflammation. Here, we discuss some of the recently identified mechanisms that showcase the role of the intestinal microbiota and barrier dysfunction in metabolic inflammation. We propose a concept by which the gut microbiota fuels metabolic inflammation and dysregulation. Here, the authors describe how metabolic disorders, such as type 2 diabetes and nonalcoholic fatty liver disease, are driven by alterations in the composition of the intestinal microbiota and its metabolites, which translocate from the gut across a disrupted intestinal barrier and contribute to metabolic inflammation.

The intestinal microbiota fuelling metabolic inflammation

Low-grade tissue inflammation induced by obesity can result in insulin resistance, which in turn is a key cause of type 2 diabetes mellitus. Cells of the innate immune system produce cytokines and other factors that impair insulin signalling, which contributes to the connection between obesity and the onset of type 2 diabetes mellitus. Here, we review the innate immune cells involved in secreting inflammatory factors in the obese state. In the adipose tissue, these cells include proinflammatory adipose tissue macrophages and natural killer cells. We also discuss the role of innate immune cells, such as anti-inflammatory adipose tissue macrophages, eosinophils, group 2 innate lymphoid cells and invariant natural killer T cells, in maintaining an anti-inflammatory and insulin-sensitive environment in the lean state. In the liver, both Kupffer cells and recruited hepatic macrophages can contribute to decreased hepatic insulin sensitivity. Proinflammatory macrophages might also adversely affect insulin sensitivity in the skeletal muscle and pancreatic β-cell function. Finally, this Review provides an overview of the mechanisms for regulating proinflammatory immune responses that could lead to future therapeutic opportunities to improve insulin sensitivity.

Regulation of metabolism by the innate immune system

Bifidobacteria or Fiber Protects against Diet-Induced Microbiota-Mediated Colonic Mucus Deterioration

A causal relationship between the pathophysiological changes in the gut epithelium and altered gut microbiota with the onset of obesity have been suggested but not defined. The aim of this study was to determine the temporal relationship between impaired intestinal barrier function and microbial dysbiosis in the small and large intestine in rodent high-fat (HF) diet-induced obesity. Rats were fed HF diet (45% fat) or normal chow (C, 10% fat) for 1, 3, or 6 wk; food intake, body weight, and adiposity were measured. Barrier function ex vivo using FITC-labeled dextran (4,000 Da, FD-4) and horseradish peroxidase (HRP) probes in Ussing chambers, gene expression, and gut microbial communities was assessed. After 1 wk, there was an immediate but reversible increase in paracellular permeability, decrease in IL-10 expression, and decrease in abundance of genera within the class Clostridia in the ileum. In the large intestine, HRP flux and abundance of genera within the order Bacteroidales increased with time on the HF diet and correlated with the onset of increased body weight and adiposity. The data show immediate insults in the ileum in response to ingestion of a HF diet, which were rapidly restored and preceded increased passage of large molecules across the large intestinal epithelium. This study provides an understanding of microbiota dysbiosis and gut pathophysiology in diet-induced obesity and has identified IL-10 and Oscillospira in the ileum and transcellular flux in the large intestine as potential early impairments in the gut that might lead to obesity and metabolic disorders.

https://www.physiology.org/doi/pdf/10.1152/ajpgi.00029.2015

Changes in intestinal barrier function and gut microbiota in high-fat diet fed rats are dynamic and region-dependent

Intestinal permeability parameters in obese patients are correlated with metabolic syndrome risk factors

Introduction; Sarcopenia are frequently observed in cancer patients and was associated with poor prognosis. Objectives; to determine the association of nutritional status, body composition, and cli...

Factors Associated with Sarcopenia in Patients with Colorectal Cancer

ContextAutism is a developmental disorder with a possible connection between dietary components and triggering or worsening of symptoms. An altered intestinal permeability might allow absorption of incompletely digested peptides (glu- ten and casein) that could produce opioid-like activity on the brain, causing significant changes in behavior. ObjectiveTo assess the intestinal permeability and nutri- tional status of participants with developmental disorders to determine if changes in the intestinal mucosal barrier and/or injury to the intercellular junctions have occurred that might justify application of further dietary modifications. DesignTo assess intestinal permeability, the research team analyzed participants' urine under fasting conditions, using gas chromatography to determine chromatographic peaks. To assess nutritional status, the team determined participants' heights and weights and performed a bioelectric bioimpedance examination at least 4 hours after their most recent meal. In addi- tion, the team determined food intake using three diet diaries. They asked participants and caregivers to register each food con- sumed during 2 nonconsecutive weekdays and 1 weekend day. SettingThe study occurred at the Ribeirao Preto School of Medicine, Sao Paulo University. ParticipantsSeven participants aged 9 to 23 years with devel- opmental disorders (the developmental group, DG) completed the study. The research team recruited them through the Association of Friends of the Autistic Persons of Ribeirao Preto in Ribeirao Preto, Brazil. The control group (CG) consisted of nonsmoking healthy volunteers in the general population who were similar in age to the experimental group and did not suffer from diseases that potentially could influence nutritional status and intestinal function. InterventionTo assess intestinal permeability, participants ingested 150 mL of an isosmolar solution of the sugars mannitol (2 g) and lactulose (7.5 g) under fasting conditions and the researchers collected all voided urine over a period of 5 hours. Outcome MeasuresUsing chromatographic peaks, the research team quantified the mannitol and lactulose in partici- pants' urine by calculating the percentage excreted in relation to the ingested amounts of sugar. This calculation gave them the lactulose-to-mannitol ratio (L/M). To evaluate nutritional status, they used data regarding bioimpedance resistance, heights, and weights to estimate lean mass and body water (in liters). They classified adults and adolescents using the body mass index (BMI). For children (2-10 y), they classified partici- pants' height-to-age and weight-to-height ratios. The research team used food intake to examine the macronutrient interval, the mean added sugar consumption, and the quantity of pro- tein, in g/kg weight. ResultsParticipants with developmental disorders (n = 7) were more likely to be overweight. Their usual diet revealed a high intake of lipids and proteins (compared to reference val- ues) and a high intake of calories and carbohydrates (%) (com- pared to CG) as well as a high intake of food sources that are important contributors of casein and gluten. The DG's (n = 7) mean mannitol excretion was lower, and their L/M higher than the CG's (n = 7) (P < .05). Their increased L/M may indicate atrophy of the intestinal-mucosa surface and/or injury to the intercellular junctions or the effect of some other abnormality. The small number of participants, however, prevented more complex statistical analysis. ConclusionsResearchers need to complete additional studies to confirm the existence of abnormalities in autistic individuals' intestines and to justify the use of dietary restrictions on gluten and casein to improve the symptoms of autism. (Altern Ther Health Med. 2012;18(1):##-##.)

Intestinal Permeability and Nutritional Status in Developmental Disorders

Frailty is associated with myosteatosis in obese patients with colorectal cancer.

Introduction: Disturbances of the gut barrier function have been related to a variety of diseases, including intestinal and extra-intestinal diseases. The intestinal permeability tests are considered useful tools for evaluating disease severity and to follow-up patients after a therapeutic intervention and indirectly assess barrier function. Objective: The aims of this review were to highlight the possible factors underlying higher intestinal permeability and the clinical conditions that have been associated with this in different age range; and also provide some insight into methodological aspects. Results and discussion: Abnormal regulation of tight junction function is the main cause of altered intestinal barrier. The impaired barrier function results in higher permeation rates of administered probes through the intestinal mucosa. Lactulose and mannitol are one of the most commonly used probes. The innocuousness and easiness of intestinal permeability tests can be explored to expand the knowledge about the clinical situations in which intestinal barrier dysfunction can be an important feature. Many factors may influence the results of the test. Researchers and healthcare professionals should try to circumvent the possible pitfalls of the intestinal permeability tests to produce consistent evidences. The use of others markers of intestinal physiology may also contribute to understand the role of barrier function in different diseases.

/pdf/intestinal-permeability-measurements-general-aspects-and-38ebbqrp6b.pdf

N.C.S. Souza

Papers

Intestinal permeability parameters in obese patients are correlated with metabolic syndrome risk factors

Factors Associated with Sarcopenia in Patients with Colorectal Cancer

Intestinal Permeability and Nutritional Status in Developmental Disorders

Frailty is associated with myosteatosis in obese patients with colorectal cancer.

Intestinal permeability measurements: general aspects and possible pitfalls