Co-administration of a probiotic strain Lactobacillus plantarum LS/07 CCM7766 with prebiotic inulin alleviates the intestinal inflammation in rats exposed to N,N-dimethylhydrazine

Inulin Attenuates Blood-Brain Barrier Permeability and Alleviates Behavioral Disorders by Modulating the TLR4/MyD88/NF-κB Pathway in Mice with Chronic Stress

Depression and vulnerability to chronic stress are associated with inflammatory responses and the loss of blood-brain barrier (BBB) integrity. Dietary fiber and its short-chain fatty acid (SCFAs) metabolites have been reported to affect neuropsychiatric disorders. Here, a 9-week treatment course of inulin (0.037 g of inulin/kcal) exhibited in chronic unpredictable mild stress (CUMS) mice led to antidepressant and anxiolytic effects, as well as improved neurogenesis and synaptic plasticity by enhancing CREB/BDNF signaling. Importantly, inulin inhibited CUMS-induced decreased BBB permeability, reduced lipopolysaccharide (LPS) brain penetration, and modulated TLR4/MyD88/NF-κB signaling to alleviate neuroinflammatory responses. Furthermore, inulin protected the gut barrier integrity and led to the increased formation of SCFAs. Enhanced SCFAs formation was strongly positively correlated with behavioral improvements, BBB integrity, and neuroinflammatory responses. We speculate that dietary fiber may be a promising nutritional intervention to reverse the effects of chronic stress by regulating metabolites and protecting the BBB integrity.

Association between Probiotics and Modulation of Gut Microbial Community Composition in Colorectal Cancer Animal Models: A Systematic Review (2010-2021)

Background

Colorectal cancer (CRC) is one of the most prevalent gastrointestinal malignancies and is considered the third major cause of mortality globally. Probiotics have been shown to protect against the CRC cascade in numerous studies.

Aims

The goal of this systematic review was to gather the preclinical studies that examined the impact of probiotics on the alteration of gut microbiota profiles (bacterial communities) and their link to colorectal carcinogenesis as well as the potential processes involved.

Methods

The search was performed using Scopus, Web of Science, and PubMed databases. Five parameters were used to develop search filters: "probiotics," "prebiotics," "synbiotics," "colorectal cancer," and "animal model."

Results

Of the 399 full texts that were screened, 33 original articles met the inclusion criteria. According to the current findings, probiotics/synbiotics could significantly attenuate aberrant crypt foci (ACF) formation, restore beneficial bacteria in the microbiota population, increase short-chain fatty acids (SCFAs), and change inflammatory marker expression.

Conclusions

The present systematic review results indicate that probiotics could modulate the gut microbial composition and immune regulation to combat/inhibit CRC in preclinical models. However, where the evidence is more limited, it is critical to transfer preclinical research into clinical data.

Pterostilbene and Probiotic Complex in Chemoprevention of Putative Precursor Lesions for Colorectal Cancer in an Experimental Model of Intestinal Carcinogenesis with 1,2-Dimethylhydrazine

Dietary supplementation with pterostilbene (PS) and/or a probiotic (PRO) may ameliorate the intestinal microbiota in disease conditions. This study aims to evaluate PS and PRO for the chemoprevention of putative precursor lesions for colorectal cancer (CRC) in an experimental model of intestinal carcinogenesis with 1,2-dimethylhydrazine (1,2-DMH). Sixty male Wistar rats were equally divided into five groups: Sham, 1,2-DMH, 1,2-DMH + PS, 1,2-DMH + PRO, and 1,2-DMH + PS + PRO. PRO (5 × 107/mL) was offered in water, and PS (300 ppm) was provided in the diet ad libitum. 1,2-DMH (20 mg/kg/week) was administered for 15 consecutive weeks. In the 25th week, proctocolectomy was conducted. PRO alone and PRO combined with PS were the best intervention strategies to improve experimental 1,2-DMH-induced CRC regarding several parameters of carcinogenesis. Our findings may contribute to the development of novel preventive strategies for CRC and may help to identify novel modulators of colon carcinogenesis.

Inulin fructans in diet: Role in gut homeostasis, immunity, health outcomes and potential therapeutics

Inulin consumption in both humans and animal models is recognized for its prebiotic action with the most consistent change that lies in enhancing the growth and functionality of Bifidobacterium bacteria, as well as its effect on host gene expression and metabolism. Further, inulin-type fructans are utilized in the colon by bacterial fermentation to yield short-chain fatty acids (SCFAs), which play important role in its biological effects both locally inside the gut and in systemic actions. The gut symbiosis sustained by inulin supplementation among other dietary fibers exerts preventive and/or therapeutic options for many metabolic disorders including obesity, type 2 diabetes mellitus, cardiometabolic diseases, kidney diseases and hyperuricemia. Although, gastrointestinal negative effects due to inulin consumption were reported, such as gastrointestinal symptoms in humans and exacerbated inflammatory bowel disease (IBD) in mice. This comprehensive review aims to present the whole story of how inulin functions as a prebiotic at cellular levels and the interplay between physiological, functional and immunological responses inside the animal or human gut as influenced by inulin in diets, in context to its structural composition. Such review is of importance to identify management and feed strategies to optimize gut health, for instance, consumption of the tolerated doses to healthy adults of 10 g/day of native inulin or 5 g/day of naturally inulin-rich chicory extract. In addition, inulin-drug interactions should be further clarified particularly if used as a supplement for the treatment of degenerative diseases (e.g., diabetes) over a long period. The combined effect of probiotics and inulin appears more effective, and more research on this synergy is still needed.

2'-Fucosyllactose promotes Lactobacillus rhamnosus KLDS 8001 to repair LPS-induced damage in Caco-2 cells

The aim of this study was to investigate the effect of 2'-fucosyllactose (2'-FL) on the repair of monolayer barrier damage in Caco-2 cells by Lactobacillus rhamnosus KLDS 8001 (KLDS 8001). The results showed that the addition of 2'-FL not only promoted the adhesion ability of KLDS 8001 to Caco-2 cells but also improved the anti-adhesive effect of pathogenic bacteria. Compared with 2'-FL or KLDS 8001 alone, 2'-FL+KLDS 8001 significantly reduced lipopolysaccharide (LPS)-induced malondialdehyde (MDA), lactate dehydrogenase (LDH) release, and cytokine (IL-1β, IL-6, and TNF-α) production. In addition, 2'-FL effectively promoted the transmembrane electrical resistance (TEER), cell viability, and cellular permeability of KLDS 8001 repaired damaged cells with dose-dependent properties. The mRNA and protein expression of Zonula Occludens-1 (ZO-1), Occludin, and Claudin-1 were also upregulated in the KLDS 8001 and 2'-FL co-treated treatment group. It was speculated that 2'-FL could effectively regulate the interaction between KLDS 8001 and intestinal epithelial cells to play a role in maintaining intestinal barrier function and avoiding pathogenic bacteria invasion. PRACTICAL APPLICATIONS: As the most widely used human milk oligosaccharides (HMOs), 2'-FL is vital for maintaining infant intestinal health. Our study found that the addition of 2'-FL promoted KLDS 8001 adhesion, anti-adhesion of pathogenic bacteria, anti-inflammatory capacity, repair of barrier damage, and tight junction protein expression, providing a new strategy to protect infant intestinal health and prevent various intestinal diseases.

Dietary Inulin Increases Lactiplantibacillus plantarum Strain Lp900 Persistence in Rats Depending on the Dietary-Calcium Level

Synbiotics are food supplements that combine probiotics and prebiotics to synergistically elicit health benefits in the consumer. Lactiplantibacillus plantarum strains display high survival during transit through the mammalian gastrointestinal tract and were shown to have health-promoting properties. Growth on the fructose polysaccharide inulin is relatively uncommon in L. plantarum, and in this study we describe FosE, a plasmid-encoded β-fructosidase of L. plantarum strain Lp900 which has inulin-hydrolyzing properties. FosE contains an LPxTG-like motif involved in sortase-dependent cell wall anchoring but is also (partially) released in the culture supernatant. In addition, we examined the effect of diet supplementation with inulin on the intestinal persistence of Lp900 in adult male Wistar rats in diets with distinct calcium levels. Inulin supplementation in high-dietary-calcium diets significantly increased the intestinal persistence of L. plantarum Lp900, whereas this effect was not observed upon inulin supplementation of the low-calcium diet. Moreover, intestinal persistence of L. plantarum Lp900 was determined when provided as a probiotic (by itself) or as a synbiotic (i.e., in an inulin suspension) in rats that were fed unsupplemented diets containing the different calcium levels, revealing that the synbiotic administration increased bacterial survival and led to higher abundance of L. plantarum Lp900 in rats, particularly in a low-calcium-diet context. Our findings demonstrate that inulin supplementation can significantly enhance the intestinal delivery of L. plantarum Lp900 but that this effect strongly depends on calcium levels in the diet.IMPORTANCE Synbiotics combine probiotics with prebiotics to synergistically elicit a health benefit in the consumer. Previous studies have shown that prebiotics can selectively stimulate the growth in the intestine of specific bacterial strains. In synbiotic supplementations the prebiotics constituent could increase the intestinal persistence and survival of accompanying probiotic strain(s) and/or modulate the endogenous host microbiota to contribute to the synergistic enhancement of the health-promoting effects of the synbiotic constituents. Our study establishes a profound effect of dietary-calcium-dependent inulin supplementation on the intestinal persistence of inulin-utilizing L. plantarum Lp900 in rats. We also show that in rats on a low-dietary-calcium regime, the survival and intestinal abundance of L. plantarum Lp900 are significantly increased by administering it as an inulin-containing synbiotic. This study demonstrates that prebiotics can enhance the intestinal delivery of specific probiotics and that the prebiotic effect is profoundly influenced by the calcium content of the diet.

Oncopreventive effects of theanine and theobromine on dimethylhydrazine-induced colon cancer model

Theanine and theobromine are abundantly present in tea and cocoa, respectively. This study was performed to assess the chemopreventive effects of these phytochemicals, alone or together, on dimethylhydrazine (DMH)-induced colon cancer. Thirty male Wistar rats were divided into five groups and subcutaneously injected with saline (negative control group) or 30 mg/kg DMH (the other groups) two times/week for 12 weeks. The negative and positive control animals were orally treated with drinking water, and the other groups were gavaged with theanine (400 mg/kg), theobromine (100 mg/kg), or their mixture for two weeks before and throughout the injection period. At the end of the study, the morphological and histopathological features, Ki-67 proliferation marker, and the expression of Akt/mTOR, JAK2/STAT3, MAPK/ERK, and TGF-β/Smad pathways were investigated. Theanine and theobromine, alone or together, reduced the number of cancerous and precancerous lesions, the volume of tumors, the Ki-67 immunostaining, and the expression of Akt/mTOR and JAK2/STAT3 oncogenic pathways. The simultaneous treatment was more effective in the down-regulation of Akt and mTOR compared to either theanine or theobromine alone. Theobromine administration also caused more inhibitory effects on the Ki-67 and Akt/mTOR expression than theanine. Besides, all dietary interventions increased the mRNA and protein expression of Smad2. In conclusion, theanine and theobromine, alone and in combination, inhibited tumorigenesis through down-regulation of the Akt/mTOR and JAK2/STAT3 pathways and an increment of the Smad2 tumor suppressor. The inhibition of the Akt/mTOR pathway was more pronounced by simultaneous treatment.

Lactobacillus plantarum inhibited the inflammatory response induced by enterotoxigenic Escherichia coli K88 via modulating MAPK and NF-κB signalling in intestinal porcine epithelial cells

AIMS

To investigate the effects of Lactobacillus plantarum on inflammatory responses induced by ETEC K88 and explore the underlying molecular mechanisms.

METHODS AND RESULTS

Intestinal porcine cells (IPEC-1) were incubated with 0 or 1 × 10⁸  CFU per well L. plantarum for 4 h, and then these cells were challenged with 0 or 1 × 10⁸  CFU per well ETEC K88 for 2 h. The results showed that pre-treatment of IPEC-1 cells with L. plantarum prevented the increases in the transcript abundance of interleukin-1α (IL-1α), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumour necrosis factor-α (TNF-α) (P < 0·05) caused by ETEC K88. Additionally, L. plantarum inhibited the reduction in peroxisome proliferator-activated receptor-γ (PPAR-γ) expression caused by ETEC K88 (P < 0·05). Moreover, L. plantarum pre-treatment downregulated the phosphorylation levels of c-Jun N-terminal kinase (JNK), extracellular regulated protein kinases 1 and 2 (ERK1/2) and p38 and the nuclear concentration of nuclear factor kappa B p65 (NF-κB p65) (P < 0·05) compared with ETEC K88 group. Silencing experiment further supported that the protective effect of L. plantarum P might mediated by suppression of ETEC-provoked activation of MAPK and NF-κB signalling pathways.

CONCLUSIONS

Lactobacillus plantarum inhibited the inflammatory response induced by ETEC K88 in IPEC-1 cells via modulating MAPK and NF-κB signalling.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study elucidated the underlying mechanism in which probiotics protect against intestinal inflammation caused by ETEC K88.

Amelioration of TMAO through probiotics and its potential role in atherosclerosis

Atherosclerosis is a major cause of mortalities and morbidities worldwide. It is associated with hyperlipidemia and inflammation, and become chronic by triggering metabolites in different metabolic pathways. Disturbance in the human gut microbiota is now considered a critical factor in the atherosclerosis. Trimethylamine-N-oxide (TMAO) attracts attention and is regarded as a vital contributor in the development of atherosclerosis. TMAO is generated from its dietary precursors choline, carnitine, and phosphatidylcholine by gut microbiota into an intermediate compound known as trimethylamine (TMA), which is then oxidized into TMAO by hepatic flavin monooxygenases. The present review focus on advances in TMAO preventing strategies through probiotics, including, modulation of gut microbiome, metabolomics profile, miRNA, or probiotic antagonistic abilities. Furthermore, possible recommendations based on relevant literature have been presented, which could be applied in probiotics and atherosclerosis-preventing strategies.

Chemoprevention of Colorectal Cancer by Dietary Compounds

Colorectal cancer is one of the leading causes of death, and the third most diagnosed type of cancer, worldwide. It is most common amongst men and women over 50 years old. Risk factors include smoking, alcohol, diet, physical inactivity, genetics, alterations in gut microbiota, and associated pathologies (diabetes, obesity, chronic inflammatory bowel diseases). This review will discuss, in detail, the chemopreventive properties of some dietary compounds (phenolic compounds, carotenoids, iridoids, nitrogen compounds, organosulfur compounds, phytosterols, essential oil compounds, polyunsaturated fatty acids and dietary fiber) against colorectal cancer. We present recent data, focusing on in vitro, laboratory animals and clinical trials with the previously mentioned compounds. The chemopreventive properties of the dietary compounds involve multiple molecular and biochemical mechanisms of action, such as inhibition of cell growth, inhibition of tumor initiation, inhibition of adhesion, migration and angiogenesis, apoptosis, interaction with gut microbiota, regulation of cellular signal transduction pathways and xenobiotic metabolizing enzymes, etc. Moreover, this review will also focus on the natural dietary compounds' bioavailability, their synergistic protective effect, as well as the association with conventional therapy. Dietary natural compounds play a major role in colorectal chemoprevention and continuous research in this field is needed.

Diets, functional foods, and nutraceuticals as alternative therapies for inflammatory bowel disease: Present status and future trends

Inflammatory bowel disease (IBD) is a serious health concern among western societies. The disease is also on the rise in some East Asian countries and in Australia. Health professionals and dietitians around the world are facing an unprecedented challenge to prevent and control the increasing prevalence of IBD. The current therapeutic strategy that includes drugs and biological treatments is inefficient and are associated with adverse health consequences. In this context, the use of natural products is gaining worldwide attention. In vivo studies and clinical evidence suggest that well-planned dietary regimens with specific nutrients can alleviate gastrointestinal inflammation by modulating inflammatory cytokines, such as tumor necrosis factor α (TNF-α), interleukin 1 (IL-1), IL-6, IL-1β, and IL-10. Alternatively, the avoidance of high-fat and high-carbohydrate diets is regarded as an effective tool to eliminate the causes of IBD. Many functional foods and bioactive components have received attention for showing strong therapeutic effects against IBD. Both animal and human studies suggest that bioactive functional foods can ameliorate IBD by downregulating the pro-inflammatory signaling pathways, such as nuclear factor κB, STAT1, STAT6, and pro-inflammatory cytokines, including IL-1β, IL-4, IL-6, COX-2, TNF-α, and interferon γ. Therefore, functional foods and diets have the potential to alleviate IBD by modulating the underlying pathogenic mechanisms. Future comprehensive studies are needed to corroborate the potential roles of functional foods and diets in the prevention and control of IBD.

Beneficial effect of synbiotics on experimental colon cancer in rats

BACKGROUND/AIMS

The aim of this study was to investigate the influence of a synbiotic preparation (a mixture of six probiotics and a prebiotic) on aberrant crypt foci (ACF) formation, dysplasia, inflammation, and colitis-like lesions in experimental colon cancer in rats.

MATERIALS AND METHODS

Sixty male rats were categorized into three groups of 20 animals each. Group A was administered 1,2-dimethylydrazine, 15 mg/kg body weight (BW), once a week for 2 weeks. Group B was administered 1,2-dimethylydrazine at the same dose plus synbiotic, started after the second dose of carcinogen and lasted for 5 weeks. Group C was administered synbiotic plus carcinogen from the beginning of the experiment and lasted for 7 weeks. Animals were killed at the end of week 7.

RESULTS

At the end of the experiment, the animals that received carcinogen plus the synbiotic had 100%, whereas the animals that received only carcinogen has 70% survival. Animals of groups B and C had significantly lower percentage of inflammation, colitis-like lesions, and ACF dysplasia than animals of group A, whereas those of group C had the least pathological lesions.

CONCLUSION

Synbiotics seem to protect against the appearance of preneoplastic colon lesions in rats. The results of this experimental study suggest that treatment with a synbiotic preparation exerts significant antimutagenic properties against the development of preneoplastic lesions in rats.

The Effect of Light Exposure at Night (LAN) on Carcinogenesis via Decreased Nocturnal Melatonin Synthesis

In mammals, a master clock is located within the suprachiasmatic nucleus (SCN) of the hypothalamus, a region that receives input from the retina that is transmitted by the retinohypothalamic tract. The SCN controls the nocturnal synthesis of melatonin by the pineal gland that can influence the activity of the clock's genes and be involved in the inhibition of cancer development. On the other hand, in the literature, some papers highlight that artificial light exposure at night (LAN)-induced circadian disruptions promote cancer. In the present review, we summarize the potential mechanisms by which LAN-evoked disruption of the nocturnal increase in melatonin synthesis counteracts its preventive action on human cancer development and progression. In detail, we discuss: (i) the Warburg effect related to tumor metabolism modification; (ii) genomic instability associated with L1 activity; and (iii) regulation of immunity, including regulatory T cell (Treg) regulation and activity. A better understanding of these processes could significantly contribute to new treatment and prevention strategies against hormone-related cancer types.

Cytokine production in vitro and in rat model of colitis in response to Lactobacillus plantarum LS/07

Over the past decade, it has become clear that specific probiotic lactobacilli are valuable in the prevention and treatment of infectious and inflammatory diseases of gastrointestinal tract but their successful application would benefit greatly from a better understanding of the mechanisms of individual strains. Hence, each probiotic strain should be characterized for their immune activity before being proposed for clinical applications. The aim of the study was to characterize the immunomodulatory activity of the strain Lactobacillus (L.) plantarum LS/07 in vitro using functional gut model and to study its anti-inflammatory potential in dextran sulphate sodium (DSS)-induced colitis in rats. We showed that L. plantarum LS/07 induced production of IL-10 in macrophages derived from blood monocytes as well as monocyte/macrophages cell line stimulated indirectly via enterocytes in vitro. In rat model of colitis, L. plantarum LS/07 attenuated the DSS-induced signs of inflammatory process in colon such as weight loss, diarrhoea, infiltration of inflammatory cells associated with decreased colon weight/length ratio, inhibited gut mucosa destruction and depletion of goblet cells. Moreover, the strain increased the concentration of anti-inflammatory cytokine IL-10 in mucosal tissue. In conclusion, the protective effects of L. plantarum LS/07 in the DSS-induced colitis model seem to be related to the stimulation of IL-10 and the restoration of goblet cells and indicate it as a good candidate to prevent and treat diseases associated with inflammation.

Attention deficit hyperactivity disorder may be a highly inflammation and immune-associated disease (Review)

Attention deficit hyperactivity disorder (ADHD) is a common behavioral disorder. Previous research has indicated that genetic factors, family education, environment and dietary habits are associated with ADHD. It has been determined that in China many children with ADHD also have allergic rhinitis or asthma. These children are more susceptible to the common cold or upper respiratory infections compared with normal healthy children. Additionally, the common cold or an upper respiratory infection may lead to disease recurrence or worsen the symptoms in these children. Previous studies have determined that ADHD may have a close association with allergic disease. Based on the clinically observed phenomenon and previous studies, it was hypothesized that ADHD is a high inflammation and immune‑associated disease. Therefore, the authors designed clinical and animal experiments to test this hypothesis in the future. Immune system disorders may be a novel part of the etiology of ADHD. The current report may have implications for future clinical practice.

Evidence of the Anti-Inflammatory Effects of Probiotics and Synbiotics in Intestinal Chronic Diseases

Probiotics and synbiotics are used to treat chronic diseases, principally due to their role in immune system modulation and the anti-inflammatory response. The present study reviewed the effects of probiotics and synbiotics on intestinal chronic diseases in in vitro, animal, and human studies, particularly in randomized clinical trials. The selected probiotics exhibit in vitro anti-inflammatory properties. Probiotic strains and cell-free supernatants reduced the expression of pro-inflammatory cytokines via action that is principally mediated by toll-like receptors. Probiotic administration improved the clinical symptoms, histological alterations, and mucus production in most of the evaluated animal studies, but some results suggest that caution should be taken when administering these agents in the relapse stages of IBD. In addition, no effects on chronic enteropathies were reported. Probiotic supplementation appears to be potentially well tolerated, effective, and safe in patients with IBD, in both CD and UC. Indeed, probiotics such as Bifidobacterium longum 536 improved the clinical symptoms in patients with mild to moderate active UC. Although it has been proposed that probiotics can provide benefits in certain conditions, the risks and benefits should be carefully assessed before initiating any therapy in patients with IBD. For this reason, further studies are required to understand the precise mechanism by which probiotics and synbiotics affect these diseases.

Effect of Inulin on Proteome Changes Induced by Pathogenic Lipopolysaccharide in Human Colon

In the present study, the protective role of inulin against lipopolysaccharide (LPS)-induced oxidative stress was evaluated on human colonic mucosa using a proteomic approach. Human colonic mucosa and submucosa were sealed between two chambers, with the luminal side facing upwards and overlaid with Krebs (control), LPS or LPS+ inulin IQ solution. The solutions on the submucosal side (undernatants) were collected following 30 min of mucosal exposure. iTRAQ based analysis was used to analyze the total soluble proteomes from human colonic mucosa and submucosa treated with different undernatants. Human colonic muscle strips were exposed to the undernatants to evaluate the response to acetylcholine. Inulin exposure was able to counteract, in human colonic mucosa, the LPS-dependent alteration of some proteins involved in the intestinal contraction (myosin light chain kinase (MLCK), myosin regulatory subunit (MYL)), to reduce the up-regulation of two proteins involved in the radical-mediated oxidative stress (the DNA-apurinic or apyrimidinic site) lyase) APEX1 and the T-complex protein 1 subunit eta (CCT7) and to entail a higher level of some detoxification enzymes (the metallothionein-2 MT2A, the glutathione-S-transferase K GSTk, and two UDP- glucuronosyltransferases UGT2B4, UGT2B17). Inulin exposure was also able to prevent the LPS-dependent intestinal muscle strips contraction impairment and the mucosa glutathione level alterations. Exposure of colonic mucosa to inulin seems to prevent LPS-induced alteration in expression of some key proteins, which promote intestinal motility and inflammation, reducing the radical-mediated oxidative stress.

Anti-cancer effect of lactic acid bacteria expressing antioxidant enzymes or IL-10 in a colorectal cancer mouse model

The association between inflammatory bowel diseases and colorectal cancer is well documented. The genetic modification of lactic acid bacteria as a tool to increase the anti-inflammatory potential of these microorganisms has also been demonstrated. Thus the aim of the present work was to evaluate the anti-cancer potential of different genetically modified lactic acid bacteria (GM-LAB) producing antioxidant enzymes (catalase or superoxide dismutase) or the anti-inflammatory cytokine IL-10 (protein or DNA delivery) using a chemical induced colon cancer murine model. Dimethilhydrazine was used to induce colorectal cancer in mice. The animals received GM-LAB producing anti-oxidant enzymes, IL-10 or a mixture of different GM-LAB. Intestinal damage, enzyme activities and cytokines were evaluated and compared to the results obtained from mice that received the wild type strains from which derived the GM-LAB. All the GM-LAB assayed showed beneficial effects against colon cancer even though they exerted different mechanisms of action. The importance to select LAB with innate beneficial properties as the progenitor strain was demonstrated with the GM-LAB producing anti-oxidant enzymes. In addition, the best effects for the mixtures GM-LAB that combine different anti-inflammatory mechanism. Results indicate that mixtures of selected LAB and GM-LAB could be used as an adjunct treatment to decrease the inflammatory harmful environment associated to colorectal cancer, especially for patients with chronic intestinal inflammation who have an increased risk to develop colorectal cancer.

Modulation of Dendritic-Epithelial Cell Responses against Sphingomonas Paucimobilis by Dietary Fibers

Non-fermenting Gram-negative bacilli, such as Sphingomonas paucimobilis (S.paucimobilis), are among the most widespread causes of nosocomial infections. Up to now, no definitive guidelines exist for antimicrobial therapy for S. paucimobilis infections. As we have shown that some dietary fibers exhibit pronounced immune-regulatory properties, we hypothesized that specific immune active dietary fibers might modulate the responses against S. paucimobilis. We studied the immunomodulatory effects of dietary fibers against S. paucimobilis on cytokine release and maturation of human dendritic cells (DCs) in co-cultures of DCs and intestinal epithelial cells (IECs). S. paucimobilis infection resulted in increased release of pro-inflammatory cytokines and chemokines by DCs/IECs; these effects were strongly attenuated by specific dietary fibers. Chicory inulin, sugar beet pectin, and both starches had the strongest regulatory effects. IL-12 and TNF-α were drastically diminished upon exposure to chicory inulin and sugar beet pectin, or both starches. High-maize 260, was more effective in the reduction of chemokine release than the others fibers tested. In summary, chicory inulin, sugar beet pectin, High-maize 260, and Novelose 330 attenuate S. paucimobilis-induced cytokines. These results demonstrate that dietary fibers with a specific chemical composition can be used to manage immune responses against pathogens such as S. paucimobilis.

Obesity-Driven Gut Microbiota Inflammatory Pathways to Metabolic Syndrome

The intimate interplay between immune system, metabolism, and gut microbiota plays an important role in controlling metabolic homeostasis and possible obesity development. Obesity involves impairment of immune response affecting both innate and adaptive immunity. The main factors involved in the relationship of obesity with inflammation have not been completely elucidated. On the other hand, gut microbiota, via innate immune receptors, has emerged as one of the key factors regulating events triggering acute inflammation associated with obesity and metabolic syndrome. Inflammatory disorders lead to several signaling transduction pathways activation, inflammatory cytokine, chemokine production and cell migration, which in turn cause metabolic dysfunction. Inflamed adipose tissue, with increased macrophages infiltration, is associated with impaired preadipocyte development and differentiation to mature adipose cells, leading to ectopic lipid accumulation and insulin resistance. This review focuses on the relationship between obesity and inflammation, which is essential to understand the pathological mechanisms governing metabolic syndrome.