Importance of Probiotics in Fish Aquaculture: Towards the Identification and Design of Novel Probiotics.

Aquaculture is a growing industry worldwide, but it faces challenges related to animal health. These challenges include infections by parasites, bacteria, and viral pathogens. These harmful pathogens have devastating effects on the industry, despite efforts to control them through vaccination and antimicrobial treatments. Unfortunately, these measures have proven insufficient to address the sanitary problems, resulting in greater environmental impact due to the excessive use of antimicrobials. In recent years, probiotics have emerged as a promising solution to enhance the performance of the immune system against parasitic, bacterial, and viral pathogens in various species, including mammals, birds, and fish. Some probiotics have been genetically engineered to express and deliver immunomodulatory molecules. These promote selective therapeutic effects and specific immunization against specific pathogens. This review aims to summarize recent research on the use of probiotics in fish aquaculture, with a particular emphasis on genetically modified probiotics. In particular, we focus on the advantages of using these microorganisms and highlight the main barriers hindering their widespread application in the aquaculture industry.

Bifidobacterium longum LBUX23 Isolated from Feces of a Newborn; Potential Probiotic Properties and Genomic Characterization.

Bifidobacterium longum is considered a microorganism with probiotic potential, which has been extensively studied, but these probiotic effects are strain dependent. This work aims to characterize the probiotic potential, based on the biochemical and genomic functionality, of B. longum LBUX23, isolated from neonates' feces. B. longum LBUX23 contains one circular genome of 2,287,838 bp with a G+C content of 60.05%, no plasmids, no CRISPR-Cas operon, possesses 56 tRNAs, 9 rRNAs, 1 tmRNA and 1776 coding sequences (CDSs). It has chromosomally encoded resistance genes to ampicillin and dicloxacillin, non-hemolytic activity, and moderate inhibition of Escherichia coli ATCC 25922 and to some emergent pathogen's clinical strains. B. longum LBUX23 was able to utilize lactose, sucrose, fructooligosaccharides (FOS), and lactulose. The maximum peak of bacterial growth was observed in sucrose and FOS at 6 h; in lactose and lactulose, it was shown at 8 h. B. longum LBUX23 can survive in gastrointestinal conditions (pH 4 to 7). A decrease in survival (96.5 and 93.8%) was observed at pH 3 and 3.5 during 120 min. argC, argH, and dapA genes could be involved in this tolerance. B. longum LBUX23 can also survive under primary and secondary glyco- or tauro-conjugated bile salts, and a mixture of bile salts due to the high extracellular bile salt hydrolase (BSH) activity (67.3 %), in taurocholic acid followed by taurodeoxycholic acid (48.5%), glycocholic acid (47.1%), oxgall (44.3%), and glycodeoxycholic acid (29.7%) probably due to the presence of the cbh and gnlE genes which form an operon (start: 119573 and end: 123812). Low BSH activity was determined intracellularly (<7%), particularly in glycocholic acid; no intracellular activity was shown. B. longum LBUX23 showed antioxidant effects in DPPH radical, mainly in intact cells (27.4%). In the case of hydroxyl radical scavenging capacity, cell debris showed the highest reduction (72.5%). In the cell-free extract, superoxide anion radical scavenging capacity was higher (90.5%). The genome of B. longum LBUX23 contains PNPOx, AhpC, Bcp, trxA, and trxB genes, which could be involved in this activity. Regarding adherence, it showed adherence up to 5% to Caco-2 cells. B. longum LBUX23 showed in vitro potential probiotic properties, mainly in BSH activity and antioxidant capacity, which indicates that it could be a good candidate for antioxidant or anti-cholesterol tests using in vivo models.

Analysis of microbiota-host communication mediated by butyrate in Atlantic salmon.

Butyrate is a microbiota-produced metabolite, sensed by host short-chain fatty acid receptors FFAR2 (Gpr43), FFAR3 (Gpr41), HCAR2 (Gpr109A), and Histone deacetylase (HDAC) that promotes microbiota-host crosstalk. Butyrate influences energy uptake, developmental and immune response in mammals. This microbial metabolite is produced by around 79 anaerobic genera present in the mammalian gut, yet little is known about the role of butyrate in the host-microbiota interaction in salmonid fish. To further our knowledge of this interaction, we analyzed the intestinal microbiota and genome of Atlantic salmon (Salmo salar), searching for butyrate-producing genera and host butyrate receptors. We identified Firmicutes, Proteobacteria, and Actinobacteria as the main butyrate-producing bacteria in the salmon gut microbiota. In the Atlantic salmon genome, we identified an expansion of genes orthologous to FFAR2 and HCAR2 receptors, and class I and IIa HDACs that are sensitive to butyrate. In addition, we determined the expression levels of orthologous of HCAR2 in the gut, spleen, and head-kidney, and FFAR2 in RTgutGC cells. The effect of butyrate on the Atlantic salmon immune response was evaluated by analyzing the pro and anti-inflammatory cytokines response in vitro in SHK-1 cells by RT-qPCR. Butyrate decreased the expression of the pro-inflammatory cytokine IL-1ß and increased anti-inflammatory IL-10 and TGF-ß cytokines. Butyrate also reduced the expression of interferon-alpha, Mx, and PKR, and decreased the viral load at a higher concentration (4 mM) in cells treated with this molecule before the infection with Infectious Pancreatic Necrosis Virus (IPNV) by mechanisms independent of FFAR2, FFAR3 and HCAR2 expression that probably inhibit HDAC. Moreover, butyrate modified phosphorylation of cytoplasmic proteins in RTgutGC cells. Our data allow us to infer that Atlantic salmon have the ability to sense butyrate produced by their gut microbiota via different specific targets, through which butyrate modulates the immune response of pro and anti-inflammatory cytokines and the antiviral response.

From In Vitro to In Vivo: A Rational Flowchart for the Selection and Characterization of Candidate Probiotic Strains in Intestinal Disorders.

Experimental and clinical evidence has demonstrated the potential of probiotic strains in the prevention or treatment of inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS). However, there is little data on what the methodology leading to the identification of such strains should be. In this work, we propose a new flowchart to identify strains with probiotic potential for the management of IBS and IBD, which we tested on a collection of 39 lactic acid bacteria and Bifidobacteria strains. This flowchart included in vitro tests of immunomodulatory properties on intestinal and peripheral blood mononuclear cells (PBMCs), assessment of the barrier-strengthening effect by measuring transepithelial electric resistance (TEER) and quantification of short-chain fatty acids (SCFAs) and aryl hydrocarbon receptor (AhR) agonists produced by the strains. The in vitro results were then combined in a principal component analysis (PCA) to identify strains associated with an anti-inflammatory profile. To validate our flowchart, we tested the two most promising strains identified in the PCA in mouse models of post-infectious IBS or chemically induced colitis to mimic IBD. Our results show that this screening strategy allows the identification of strains with potential beneficial effects on colonic inflammation and colonic hypersensitivity.

Genomic and Biochemical Characterization of Bifidobacterium pseudocatenulatum JCLA3 Isolated from Human Intestine.

Bifidobacteria have been investigated due to their mutualistic microbe-host interaction with humans throughout their life. This work aims to make a biochemical and genomic characterization of Bifidobacterium pseudocatenulatum JCLA3. By multilocus analysis, the species of B. pseudocatenulatum JCLA3 was established as pseudocatenulatum. It contains one circular genome of 2,369,863 bp with G + C content of 56.6%, no plasmids, 1937 CDSs, 54 tRNAs, 16 rRNAs, 1 tmRNA, 1 CRISPR region, and 401 operons predicted, including a CRISPR-Cas operon; it encodes an extensive number of enzymes, which allows it to utilize different carbohydrates. The ack gene was found as part of an operon formed by xfp and pta genes. Two genes of ldh were found at different positions. Chromosomally encoded resistance to ampicillin and cephalothin, non-hemolytic activity, and moderate inhibition of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 6538 were demonstrated by B. pseudocatenulatum JCLA3; it can survive 100% in simulated saliva, can tolerate primary and secondary glyco- or tauro-conjugated bile salts but not in a mix of bile; the strain did not survive at pH 1.5-5. The cbh gene coding to choloylglycine hydrolase was identified in its genome, which could be related to the ability to deconjugate secondary bile salts. Intact cells showed twice as much antioxidant activity than debris. B. pseudocatenulatum JCLA3 showed 49% of adhesion to Caco-2 cells. The genome and biochemical analysis help to elucidate further possible biotechnological applications of B. pseudocatenulatum JCLA3.

Serpin-positive Bifidobacterium breve CNCM I-5644 improves intestinal permeability in two models of irritable bowel syndrome.

Probiotic supplementation can help to mitigate the pathogenesis of irritable bowel syndrome (IBS) by reinforcing the intestinal barrier, and reducing both inflammation and proteolytic activity. Here, a combination of in vitro tests was performed on 33 Bifidobacterium strains as probiotic candidates for IBS. In addition to the classical tests performed, the detection of the serine protease inhibitor (serpin) enzyme capable of decreasing the high proteolytic activity found in IBS patients was included. Three serpin-positive strains were selected: Bifidobacterium breve CNCM I-5644, Bifidobacterium longum subsp. infantis CNCM I-5645 and B. longum CNCM I-5646 for their immunomodulation properties and protection of intestinal epithelial integrity in vitro. Furthermore, we found that B. breve CNCM I-5644 strain prevented intestinal hyperpermeability by upregulating Cingulin and Tight Junction Protein 1 mRNA levels and reducing pro-inflammatory markers. The ability of CNCM I-5644 strain to restore intestinal hyperpermeability (FITC-dextran) was shown in the murine model of low-grade inflammation induced by dinitrobenzene sulfonic acid (DNBS). This effect of this strain was corroborated in a second model of IBS, the neonatal maternal separation model in mice. Altogether, these data suggest that serpin-positive B. breve CNCM I-5644 may partially prevent disorders associated with increased barrier permeability such as IBS.

Strategies for the Identification and Assessment of Bacterial Strains with Specific Probiotic Traits.

Early in the 1900s, it was proposed that health could be improved and senility delayed by manipulating gut microbiota with the host-friendly bacteria found in yogurt. Later, in 1990, the medical community reconsidered this idea and today probiotics represent a developed area of research with a billion-dollar global industry. As a result, in recent decades, increased attention has been paid to the isolation and characterization of novel probiotic bacteria from fermented foods and dairy products. Most of the identified probiotic strains belong to the lactic acid bacteria group and the genus Bifidobacterium. However, current molecular-based knowledge has allowed the identification and culture of obligatory anaerobic commensal bacteria from the human gut, such as Akkermansia spp. and Faecalibacterium spp., among other human symbionts. We are aware that the identification of new strains of these species does not guarantee their probiotic effects and that each effect must be proved through in vitro and in vivo preclinical studies before clinical trials (before even considering it as a probiotic strain). In most cases, the identification and characterization of new probiotic strain candidates may lack the appropriate set of in vitro experiments allowing the next assessment steps. Here, we address some innovative strategies reported in the literature as alternatives to classical characterization: (i) identification of alternatives using whole-metagenome shotgun sequencing, metabolomics, and multi-omics analysis; and (ii) probiotic characterization based on molecular effectors and/or traits to target specific diseases (i.e., inflammatory bowel diseases, colorectal cancer, allergies, among others).

Functional characterization of α-Gal producing lactic acid bacteria with potential probiotic properties.

The possibility of exploiting the human immune response to glycan α-Gal for the control of multiple infectious diseases has been the objective of recent investigations. In this field of research, the strain of Escherichia coli O86:B7 has been at the forefront, but this Gram-negative microorganism presents a safety concern and therefore cannot be considered as a probiotic. To address this challenge, this study explored the identification of novel lactic acid bacteria with a safe history of use, producing α-Gal and having probiotic potential. The lactic acid bacteria were isolated from different traditionally fermented foods (kununn-zaki, kindirmo, and pulque) and were screened for the production of α-Gal and some specific probiotic potential indicators. The results showed that Ten (10) out of forty (40) [25%] of the tested lactic acid bacteria (LAB) produced α-Gal and were identified as Limosilactobacillus fermentum, Levilactobacillus brevis, Agrilactobacillus composti, Lacticaseibacillus paracasei, Leuconostoc mesenteroides and Weissella confusa. Four (4) LAB strains with highest levels of α-Gal were further selected for in vivo study using a mouse model (α1,3GT KO mice) to elucidate the immunological response to α-Gal. The level of anti-α-Gal IgG observed were not significant while the level of anti-α-Gal IgM was lower in comparison to the level elicited by E. coli O86:B7. We concluded that the lactic acid bacteria in this study producing α-Gal have potential probiotic capacity and can be further explored in α-Gal-focused research for both the prevention and treatment of various infectious diseases and probiotic development.

Bioactive Compounds in Food as a Current Therapeutic Approach to Maintain a Healthy Intestinal Epithelium.

The intestinal epithelium serves as an effective barrier against the external environment, hampering the passage of potentially harmful substances (such as pathogenic microbes) that could trigger an exacerbated host immune response. The integrity of this barrier is thus essential for the maintenance of proper intestinal homeostasis and efficient protective reactions against chemical and microbial challenges. The principal consequence of intestinal barrier defects is an increase in intestinal permeability, which leads to an increased influx of luminal stressors, such as pathogens, toxins, and allergens, which in turn trigger inflammation and immune response. The fine and fragile balance of intestinal homeostasis can be altered by multiple factors that regulate barrier function, many of which are poorly understood. This review will address the role of gut microbiota as well as food supplements (such as probiotics, prebiotics, and synbiotics) in modulating gut health and regulating intestinal barrier function. In particular, we will focus on three human pathologies: inflammatory bowel disease, irritable bowel syndrome, and food allergy.

Anti-Microbiota Vaccines Modulate the Tick Microbiome in a Taxon-Specific Manner.

The lack of tools for the precise manipulation of the tick microbiome is currently a major limitation to achieve mechanistic insights into the tick microbiome. Anti-tick microbiota vaccines targeting keystone bacteria of the tick microbiota alter tick feeding, but their impact on the taxonomic and functional profiles of the tick microbiome has not been tested. In this study, we immunized a vertebrate host model (Mus musculus) with live bacteria vaccines targeting keystone (i.e., Escherichia-Shigella) or non-keystone (i.e., Leuconostoc) taxa of tick microbiota and tested the impact of bacterial-specific antibodies (Abs) on the structure and function of tick microbiota. We also investigated the effect of these anti-microbiota vaccines on mice gut microbiota composition. Our results showed that the tick microbiota of ticks fed on Escherichia coli-immunized mice had reduced Escherichia-Shigella abundance and lower species diversity compared to ticks fed on control mice immunized with a mock vaccine. Immunization against keystone bacteria restructured the hierarchy of nodes in co-occurrence networks and reduced the resistance of the bacterial network to taxa removal. High levels of E. coli-specific IgM and IgG were negatively correlated with the abundance of Escherichia-Shigella in tick microbiota. These effects were not observed when Leuconostoc was targeted with vaccination against Leuconostoc mesenteroides. Prediction of functional pathways in the tick microbiome using PICRUSt2 revealed that E. coli vaccination reduced the abundance of lysine degradation pathway in tick microbiome, a result validated by qPCR. In contrast, the gut microbiome of immunized mice showed no significant alterations in the diversity, composition and abundance of bacterial taxa. Our results demonstrated that anti-tick microbiota vaccines are a safe, specific and an easy-to-use tool for manipulation of vector microbiome. These results guide interventions for the control of tick infestations and pathogen infection/transmission.

Role of Gut Microbiota and Probiotics in Colorectal Cancer: Onset and Progression.

The gut microbiota plays an important role in maintaining homeostasis in the human body, and the disruption of these communities can lead to compromised host health and the onset of disease. Current research on probiotics is quite promising and, in particular, these microorganisms have demonstrated their potential for use as adjuvants for the treatment of colorectal cancer. This review addresses the possible applications of probiotics, postbiotics, synbiotics, and next-generation probiotics in colorectal cancer research.

Antioxidant and Anti-Inflammatory Properties of Probiotic Candidate Strains Isolated during Fermentation of Agave (Agave angustifolia Haw).

Agave species are a source of diverse products for human use, such as food, fiber, and beverages, which include mezcal, a distilled beverage produced by spontaneous fermentation. Agave is an excellent source of high amounts of sugars, minerals, and phenolic compounds, which favor the growth of lactic acid bacteria (LAB) and yeast communities. In this work, 20 promising LAB strains with probiotic characteristics were isolated from the agave fermentation stage in mezcal production. The strains belonged to Lactobacillus plantarum (15), Lactobacillus rhamnosus (2), Enterococcus faecium (2), and Lactococcus lactis (1). These isolates were characterized for their resistance under gastrointestinal conditions, such as lysozyme, acid pH, and bile salts. In addition, the adherence of these LABs to human intestinal epithelial cells (Caco-2 and HT-29 cells) was tested in vitro and their antioxidant and immunomodulatory profile was determined using cellular models. Lactobacillus rhamnosus LM07 and Lactobacillus plantarum LM17 and LM19 strains were selected for their antioxidant properties, and their capacities in an oxidative stress model in intestinal epithelial cells IECs (Caco-2 and HT-29 cells) in the presence of hydrogen peroxide were evaluated. Interestingly, Lactobacillus rhamnosus LM07 and Lactobacillus plantarum LM17 and LM19 strains showed anti-inflammatory properties in TNF-α-stimulated HT-29 cells. Subsequently, bacterial strains exhibiting antioxidant and anti-inflammatory properties were tested in vivo in a mouse model with dinitrobenzene sulfonic acid (DNBS)-induced chronic colitis. Weight loss, intestinal permeability, and cytokine profiles were measured in mice as indicators of inflammation. One of the selected strains, Lactobacillus plantarum LM17, improved the health of the mice, as observed by reduced weight loss, and significantly decreased intestinal permeability. Altogether, our results demonstrate the potential of LAB (and lactobacilli in particular) isolated from the agave fermentation stage in mezcal production. Lactobacillus rhamnosus LM07 and Lactobacillus plantarum LM17 strains represent potential candidates for developing new probiotic supplements to treat inflammatory bowel disease (IBD).

The Administration Matrix Modifies the Beneficial Properties of a Probiotic Mix of Bifidobacterium animalis subsp. lactis BB-12 and Lactobacillus acidophilus LA-5.

Consumption of dairy products is one of the most natural ways to introduce probiotics. However, the beneficial effects of the probiotics might depend on the administration form. The aim of this study was to investigate the beneficial properties of two probiotic strains: Bifidobacterium animalis subsp. lactis (BB-12) and Lactobacillus acidophilus (LA-5) in different administration forms (capsules and yogurt). First, in vitro resistance to gastrointestinal condition, surface properties, and immunomodulation capacities were determined. Then, the anti-inflammatory properties of the probiotic strains administrated on yogurt or capsules were tested in a dinitrobenzene sulfonic acid (DNBS)-induced colitis mouse model. The survival rates of BB-12 and LA-5 strains to gastrointestinal conditions were slightly higher when yogurt was used as carrier. They showed most affinity to hexane (no-polar basic solvent) than ethyl-acetate (polar basic solvent). BB-12 showed the higher binding capacity to HT-29, Caco-2, and mucin. Both probiotic candidates suppress the secretion of IL-8 secretion by HT-29-TNF-α stimulated cells. Finally, administration of BB-12 and LA-5 strains improve colitis in mice. They protect against weight loss, inflammation, and hyperpermeability induced by DNBS. However, these anti-inflammatory effects were limited when mice were treated with the probiotic strain on a yogurt matrix. Overall results indicate that BB-12 and LA-5 positive properties are compromised depending on the matrix. Consequently, the selection of an appropriate matrix is an important criterion to conserve the positive benefits of these probiotic strains.

Butyrate mediates anti-inflammatory effects of Faecalibacterium prausnitzii in intestinal epithelial cells through Dact3.

The commensal bacterium Faecalibacterium prausnitzii plays a key role in inflammatory bowel disease (IBD) pathogenesis and serves as a general health biomarker in humans. However, the host molecular mechanisms that underlie its anti-inflammatory effects remain unknown. In this study we performed a transcriptomic approach on human intestinal epithelial cells (HT-29) stimulated with TNF-α and exposed to F. prausnitzii culture supernatant (SN) in order to determine the impact of this commensal bacterium on intestinal epithelial cells. Moreover, modulation of the most upregulated gene after F. prausnitzii SN contact was validated both in vitro and in vivo. Our results showed that F. prausnitzii SN upregulates the expression of Dact3, a gene linked to the Wnt/JNK pathway. Interestingly, when we silenced Dact3 expression, the effect of F. prausnitzii SN was lost. Butyrate was identified as the F. prausnitzii effector responsible for Dact3 modulation. Dact3 upregulation was also validated in vivo in both healthy and inflamed mice treated with either F. prausnitzii SN or the live bacteria, respectively. Finally, we demonstrated by colon transcriptomics that gut microbiota directly influences Dact3 expression. This study provides new clues about the host molecular mechanisms involved in the anti-inflammatory effects of the beneficial commensal bacterium F. prausnitzii.

Gut Microbiota Abrogates Anti-α-Gal IgA Response in Lungs and Protects against Experimental Aspergillus Infection in Poultry.

Naturally occurring human antibodies (Abs) of the isotypes IgM and IgG and reactive to the galactose-α-1,3-galactose (α-Gal) epitope are associated with protection against infectious diseases, caused by pathogens expressing the glycan. Gut microbiota bacteria expressing α-Gal regulate the immune response to this glycan in animals lacking endogenous α-Gal. Here, we asked whether the production of anti-α-Gal Abs in response to microbiota stimulation in birds, confers protection against infection by Aspergillus fumigatus, a major fungal pathogen that expresses α-Gal in its surface. We demonstrated that the oral administration of Escherichia coli O86:B7 strain, a bacterium with high α-Gal content, reduces the occurrence of granulomas in lungs and protects turkeys from developing acute aspergillosis. Surprisingly, the protective effect of E. coli O86:B7 was not associated with an increase in circulating anti-α-Gal IgY levels, but with a striking reduction of anti-α-Gal IgA in the lungs of infected turkeys. Subcutaneous immunization against α-Gal did not induce a significant reduction of lung anti-α-Gal IgA and failed to protect against an infectious challenge with A. fumigatus. Oral administration of E. coli O86:B7 was not associated with the upregulation of lung cytokines upon A. fumigatus infection. We concluded that the oral administration of bacteria expressing high levels of α-Gal decreases the levels of lung anti-α-Gal IgA, which are mediators of inflammation and lung damage during acute aspergillosis.

Probiotic Properties of Lactobacillus Strains Isolated from Table Olive Biofilms.

In this work, 16 strains with promising probiotic characteristics belonging to the Lactobacillus pentosus (13) and Lactobacillus plantarum (3) species and isolated from table olive biofilms were tested for adherence to cell lines and to solvents, immunomodulatory, and anti-proliferative properties on epithelial human cellular lines. Most Lactobacillus strains were able to regulate the production of cytokines by stimulating the production of pro-inflammatory (IL-6) and anti-inflammatory (IL-10) interleukins on macrophages, and by suppressing the secretion of IL-8 on HT-29 TNF-α-induced model. Lactobacillus strains also showed anti-proliferative activity on the HT-29 cell line. No clear relation was found between adhesion to solvents and adhesion to HT-29 human cell line. Lactobacillus pentosus LPG1, which showed the best anti-inflammatory and immunomodulatory properties, was then tested in a dinitro-benzene sulfonic acid (DNBS)-induced chronic colitis murine model. As a measure of the inflammation, gut permeability and weight loss, as well as cytokine profiles, were determined. Lactobacillus pentosus LPG1 improved mice health as observed by a significant reduction of weight loss, gut permeability, and beneficial cytokine modulation. Macroscopic scores and tissue damage were also lower in mice administered with LPG1 with respect to the DNBS-treated group. These results showed that L. pentosus LPG1 isolated from plant could have potential as probiotic for use as an anti-inflammatory and immunomodulatory agent for patients with inflammatory bowel disease.

Anthropometric measure and adipokine levels of a young undergraduate population with a usual diet / Medidas antropométricas y niveles de adipocinas de una población joven de pregrado con dieta habitual

Background: obesity is the excessive accumulation of adipose tissue related to food intake and other factors. The aim of this study was to evaluate the intake of nutrients, anthropometric parameters, health indicators, adipokines and insulin levels in a population of young undergraduates. Method: in this study, 378 young undergraduates were invited to participate. Due to the inclusion criteria and their own decision of participating, 90 attended the anthropometric, health indicators: waist circumference (WC), waist to hip ratio (WHR), waist to height ratio (WHtR), and homeostatic model assessment-insulin resistance index (HOMA-IR) studies and completed the questionnaire of frequency of food intake; and 34 participants were selected to perform the determination of biochemical parameters, insulin and adipokines levels: leptin, IL-6, IL-8, tumor necrosis factor alpha (TNF- α), monocyte chemoattractant protein-1 (MCP-1) and hepatocyte growth factor (HGF). Results: according to WC, WHR and WHtR (women: 104 ± 20, 0.87 ± 0.08, 0.6 ± 0.13; men: 112 ± 10, 0.95 ± 0.09, 0.64 ± 0.06, respectively), obese population showed health, cardiovascular and metabolic risk. Overweight population showed cardiometabolic risk. In general, lipid intake was higher than 30%, being animal fat the most consumed. The levels of leptin (women: 17.2 ± 9.2, 28 ± 11.3, 36.8 ± 17.8; men: 4.3 ± 3.6, 9.5 ± 3.1, 24.6 ± 16.4 to lean overweight and obese, respectively) and insulin (women: 408 ± 182, 438 ± 187, 768 ± 167; men: 244 ± 88, 520 ± 256, 853 ± 590) increased along with body mass index (BMI), body fat percentage (BFP), visceral fat area (VFA), WC, WHR and WHtR. Lean (2.4 ± 1.3), overweight (2.2 ± 0.9) and obese (4.3 ± 1.1) women and overweight (2.8 ± 1.2) and obese (5.0 ± 3.1) men showed insulin resistance according to HOMA-IR. Significant correlation between leptin and HOMA-IR was found (p = 0.41). BMI, BFP, VFA, WC, and WHtR positively correlated with leptin (p = 0.67, 0.75, 0.66, 0.60, 0.67, respectively) and insulin (p = 0.37, 0.40, 0.48, 0.49, 0.42, respectively), while WHR only with insulin (p = 0.43). No significant differences were found in the other adipokines. Conclusion: the use of health indicators such VFA, WC, WHR, WHtR and HOMA-IR are useful tools in the determination of health, cardio vascular and metabolic risk and are correlated with levels of leptin and insulin in the studied population

Introducción: la obesidad es la acumulación excesiva de tejido adiposo relacionada con la ingesta de alimentos y otros factores. El objetivo de este estudio fue evaluar la ingesta de nutrientes, parámetros antropométricos, indicadores de salud, adipocinas y niveles de insulina en una población de jóvenes universitarios con una dieta habitual. Método: en este estudio se invitó a participar a 378 jóvenes universitarios. Debido a los criterios de inclusión y su propia decisión de participar, 90 asistieron a los estudios antropométricos y de indicadores de salud: circunferencia de cintura (WC), índice de cadera cintura (WHR), índice de cintura-talla (WHtR) y modelo homeostático de evaluación-índice de resistencia a la insulina (HOMA-IR) y completaron el cuestionario de frecuencia de ingesta de alimentos. Treinta y cuatro participantes fueron seleccionados para realizar la determinación de los parámetros bioquímicos, niveles de insulina y adipocinas (leptina, IL-6, IL-8, factor de necrosis tumoral alfa [TNF- α], proteína quimioatractante de monocitos-1 [MCP-1] y factor de crecimiento hepático [HGF]). Resultados: de acuerdo con WC, WHR y WHtR (mujeres: 104 ± 20, 0,87 ± 0,08, 0,6 ± 0,13; hombres: 112 ± 10, 0,95 ± 0,09, 0,64 ± 0,06, respectivamente), la población obesa mostró riesgo cardiovascular, metabólico y para la salud. La población con sobrepeso mostró riesgo cardiometabólico. En general, la ingesta de lípidos fue superior al 30% y la grasa animal fue la más consumida. Los niveles de leptina (mujeres: 17,2 ± 9,2, 28 ± 11,3, 36,8 ± 17,8; hombres: 4,3 ± 3,6, 9,5 ± 3,1, 24,6 ± 16,4 para delgados, sobrepeso y obesos, respectivamente) e insulina (mujeres: 408 ± 182, 438 ± 187, 768 ± 167; hombres: 244 ± 88, 520 ± 256, 853 ± 590) aumentaron junto con el índice de masa corporal (BMI), porcentaje de grasa corporal (BFP), área de grasa visceral (VFA), WC, WHR y WHtR. Las mujeres delgadas (2,4 ± 1,3), con sobrepeso (2,2 ± 0,9) y obesas (4,3 ± 1,1) y los hombres con sobrepeso (2,8 ± 1,2) y obesos (5,0 ± 3,1) mostraron resistencia a la insulina de acuerdo con HOMA-IR. Se encontró una correlación significativa entre leptina y HOMA-IR (p = 0,41). BMI, BFP, VFA, WC y WHtR correlacionaron positivamente con leptina (p = 0,67, 0,75, 0,66, 0,60 y 0,67, respectivamente) e insulina (p = 0,37, 0,40, 0,48, 0,49 y 0,42, respectivamente), mientras que el WHR solo con insulina (p = 0,43). No se encontraron diferencias signifi cativas en las otras adipocinas. Conclusión: el uso de indicadores de salud como VFA, WC, WHR, WHtR y HOMA-IR es una herramienta útil en la determinación del riesgo metabólico, cardiovascular y de salud, y dichos indicadores correlacionaron con los niveles de leptina e insulina en la población estudiada

Elucidating the Immune-Related Mechanisms by Which Probiotic Strain Lactobacillus casei BL23 Displays Anti-tumoral Properties.

We have recently described antitumor properties of Lactobacillus casei BL23 strain in both a mouse allograft model of human papilloma virus (HPV)-induced cancer and dimethylhydrazine-associated colorectal cancer. However, the mechanisms underlying these beneficial effects are still unknown. Interestingly, in vitro cellular models show that this bacterium is able to stimulate the production of high levels of IL-2. Because this cytokine has well-known antitumor properties, we decided to explore its role in the anti-cancer effects of BL23 using the HPV-induced cancer model. We found a negative correlation between IL-2 and tumor size confirming the necessity of IL-2 to protect from tumor development. Then, we blocked IL-2 synthesis using neutralizing monoclonal antibodies in mice that were challenged with lethal levels of tumor cells; this led to a significant reduction in the protective abilities of BL23. Next, we used a genetically modified strain of Lactococcus lactis to deliver exogenous IL-2 to the system, and in doing so, we were able to partially mimic the antitumor properties of BL23. Additionally, we showed the systemic role of T-cells in tumor protection through a negative correlation between tumor size and T-cells subpopulations and an increasement of BL23-specific local Foxp3 levels in tumor-bearing mice. Finally, we observed a negative correlation between tumor size and NK+ cells, but local recruitment of NK cells and cytotoxic activity appeared specific to BL23 treatment. Taken together, our data suggest that IL-2 signaling pathway plays an important role in the anti-tumoral effects of probiotic strain L. casei BL23. These results encourage further investigation in the use of probiotic strains for potential therapeutic applications to clinical practice, in particular for the treatment of colorectal cancer. Furthermore, our approach could be extended and applied to other potential beneficial microorganisms, such as gut microbiota, in order to better understand the crosstalk between microbes and the host.

Anti-tumoral Effects of Recombinant Lactococcus lactis Strain Secreting IL-17A Cytokine.

Interleukin-17A (IL-17A) is a pro-inflammatory cytokine produced by TH17 cells that participates and contributes in host defense and autoimmune disease. We have recently reported antitumor properties of the probiotic strain of Lactobacillus casei BL23 in mice and TH17 cells was shown to play an important role in this beneficial effect. In order to better understand the role of IL-17A in cancer, we constructed a recombinant strain of Lactococcus lactis producing this cytokine and we determined its biological activity in: (i) a bioassay test for the induction of IL-6 production by murine fibroblasts 3T3 L1 cells line and (ii) in a mouse allograft model of human papilloma virus (HPV)-induced cancer. Our data show that recombinant L. lactis produces and efficiently secretes biologically active IL-17A cytokine. Interestingly, ∼26% of mice intranasally treated with L. lactis-IL-17A and challenged with TC-1 cells remained tumor free over the experiment, in contrast to control mice treated with the wild type strain of L. lactis which developed 100% of aggressive tumors. In addition, the median size of the ∼74% tumor-bearing mice treated with recombinant L. lactis-IL-17A, was significantly lower than mice treated with L. lactis-wt. Altogether, our results demonstrate that intranasal administration with L. lactis secreting IL-17A results in a partial protection against TC-1-induced tumors in mice, confirming antitumor effects of this cytokine in our cancer model.

Identification of novel anti-inflammatory probiotic strains isolated from pulque.

Probiotics are live microorganisms which when administered in adequate amounts, confer health benefits on the host. Their use is more and more widespread for both prevention and treatment of diseases, including traveler's diarrhea and inflammatory bowel diseases (IBDs). In this work, we isolated and characterized novel candidate probiotic strains from pulque (xaxtle), a traditional Mexican alcoholic fermented beverage. A total of 14 strains were obtained from xaxtle samples isolated from three different Mexican regions. Species identification was performed by biochemical methods and 16S rRNA gene targeted PCR. The isolates belonged to the Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, and Lactobacillus composti phylogenetic groups, with L. brevis being the most dominant group. Bacteria were tested for lysozyme, low pH, and bile acid resistance. Moreover, the strains were tested for adherence to human intestinal epithelial cells and screened for their immunomodulatory properties using a cellular model. Selected bacterial strains with anti-inflammatory properties were then tested in vivo in a dinitro-benzene sulfonic acid (DNBS)-induced chronic colitis mouse model, and weight loss, gut permeability, and cytokine profiles were measured as readouts of inflammation. One of the selected strains, Lactobacillus sanfranciscensis LBH1068, improved mice health as observed by a reduction of weight loss, significant decreases in gut permeability, and cytokine modulation. Altogether, our results highlighted the potential of lactobacilli isolated from pulque and in particular the strain L. sanfranciscensis LBH1068 as a novel probiotic to treat IBD.