Dietary fatty acids and immune response to food-borne bacterial infections

Effects of glycerol monolaurate on estradiol and follicle-stimulating hormones, offspring quality, and mRNA expression of reproductive-related genes of zebrafish (Danio rerio) females

This study aims to explore whether glycerol monolaurate (GML) can improve reproductive performance of female zebrafish (Danio rerio) and the survival percentage of their offspring. Three kinds of isonitrogenous and isolipid diets, including basal diet (control) and basal diet containing 0.75 g/kg GML (L_GML) and 1.5 g/kg GML (H_GML), were prepared for 4 weeks feeding trial. The results show that GML increased the GSI of female zebrafish. GML also enhanced reproductive performance of female zebrafish. Specifically, GML increased spawning number and hatching rate of female zebrafish. Moreover, GML significantly increased the levels of triglycerides (TG), lauric acid, and estradiol (E2) in the ovary (P < 0.05). Follicle-stimulating hormone (FSH) levels in the ovary and brain also significantly increased in the L_GML group (P < 0.05). Besides, dietary GML regulated the hypothalamus-pituitary-gonad (HPG) axis evidenced by the changed expression levels of HPG axis-related genes in the brain and ovary of the L_GML and H_GML groups compared with the control group. Furthermore, compared with the control group, the expression levels of HPG axis-related genes (kiss2, kiss1r, kiss2r, gnrh3, gnrhr1, gnrhr3, lhβ, and esr2b) in the brain of the L_GML group were significantly increased (P < 0.05), and the expression levels of HPG axis-related genes (kiss1, kiss2, kiss2r, gnrh2, gnrh3, gnrhr4, fshβ, lhβ, esr1, esr2a, and esr2b) in the brain of the H_GML group were significantly increased (P < 0.05). These results suggest that GML may stimulate the expression of gnrh2 and gnrh3 by increasing the expression level of kiss1 and kiss2 genes in the hypothalamus, thus promoting the synthesis of FSH and E2. The expression levels of genes associated with gonadotropin receptors (fshr and lhr) and gonadal steroid hormone synthesis (cyp11a1, cyp17, and cyp19a) in the ovary were also significantly upregulated by dietary GML (P < 0.05). The increasing expression level of cyp19a also may promote the FSH synthesis. Particularly, GML enhanced the richness and diversity and regulated the species composition of intestinal microbiota in female zebrafish. Changes in certain intestinal microorganisms may be related to the expression of certain genes involved in the HPG axis. In addition, L_GML and H_GML both significantly decreased larvae mortality at 96 h post fertilization and their mortality during the first-feeding period (P < 0.05), revealing the enhanced the starvation tolerance of zebrafish larvae. In summary, dietary GML regulated genes related to HPG axis to promote the synthesis of E2 and FSH and altered gut microbiota in female zebrafish, and improved the survival percentage of their offspring.

Dietary Influences on Skin Health in Common Dermatological Disorders

The role of diet in the development of skin disorders is well-established, with nutritional deficiency often identified as a risk factor for skin diseases. Imbalances in the skin can be caused by nutritional deficiencies, excessive intake, insufficient nutrients, and hazardous ingredients. Patients frequently inquire about the impact of dietary patterns on skin health when consulting dermatologists in clinical settings. Simultaneously, the popularity of using nutritional supplements containing vitamins, minerals, and nutraceutical blends has been on the rise. It is crucial for dermatologists, primary care physicians, and other healthcare providers to be acquainted with evidence-based dietary interventions, distinguishing them from those that are more market-driven than truly efficacious. This review explores the modification of diet, encompassing both dietary exclusion and supplementation, as a therapeutic approach for conditions such as psoriasis, atopic dermatitis, bullous disease, vitiligo, and alopecia areata. A comprehensive literature search, utilizing the PubMed/Medline, Google Scholar, and Medscape databases, was conducted to investigate the relationship between each nutrient and various inflammatory skin diseases. The findings emphasize the significance of a well-balanced and thoughtfully planned diet in supplying adequate amounts of proteins, vitamins, and minerals to support optimal skin health. Additionally, this comprehensive review navigates through various dietary recommendations, offering insights into their multifaceted impacts on the immune system, gut microbiome, and skin health. The goal is to pave the way for informed and targeted dietary interventions for individuals dealing with food allergies and associated skin conditions.

Effects of monolaurin on intestinal barrier, blood biochemical profile, immunity and antioxidant function in porcine epidemic diarrhoea virus-infected piglets

The effects of monolaurin (ML) on the health of piglets infected with porcine epidemic diarrhoea virus (PEDV) have not been fully understood. This study aimed to investigate its role in blood biochemical profile, intestinal barrier function, antioxidant function and the expression of antiviral genes in piglets infected with PEDV. Thirty-two piglets were randomly divided into four groups: control group, ML group, PEDV group and ML + PEDV group. Piglets were orally administrated with ML at a dose of 100 mg/kg·BW for 7 d before PEDV infection. Results showed that PEDV infection significantly decreased D-xylose content and increased intestinal fatty acid-binding protein content, indicating that PEDV infection destroyed intestinal barrier and absorption function. While it could be repaired by ML administration. Moreover, ML administration significantly decreased plasma blood urea nitrogen and total protein content upon PEDV infection. These results suggested ML may increase protein utilisation efficiency. ML administration significantly decreased the number of large unstained cells and Hb and increased the number of leucocytes and eosinophils in the blood of PEDV-infected piglets, indicating ML could improve the immune defense function of the body. In the presence of PEDV infection, ML administration significantly increased superoxide dismutase and catalase activities in blood and colon, respectively, indicating ML could improve antioxidant capacity. Besides, ML administration reversed the expression of ISG15, IFIT3 and IL-29 throughout the small intestine and Mx1 in jejunum and ileum, indicating the body was in recovery from PEDV infection. This study suggests that ML could be used as a kind of feed additive to promote swine health upon PEDV infection.

Effect of dietary modulation of fiber and fat level on liver and kidney functions, lipid profile, antioxidant and immune parameters in growing Egyptian geese

Determining the optimal requirements from dietary fiber and fat for Egyptian geese is a matter of great concern regarding health, production and growth. Therefore, the current study estimated the effects of different dietary fiber and fat levels on functions of liver and kidney, lipid profile, immunity and antioxidant measurements of the growing Egyptian geese. 150 Egyptian goslings (4 weeks old), with almost the same body weights were randomly allocated into 6 groups (25 goslings/group). All groups were subdivided into five replicates, each replicate contains five geese. Liver and kidney functions, immunity and antioxidant parameters were not significantly affected the different studied levels of fiber and fat or by their interaction. Various levels of fiber significantly affected total cholesterol, triglycerides, LDL-cholesterol and VLDL-cholesterol in a concentration-dependent manner and the lowest the lipid profile values were obtained at 12%. In conclusion, the present findings show that use of dietary fiber up to 12% and 5% dietary fat showed no detrimental effects on the immune status and general health of geese and resulted in the preferable lipid profile. This experiment provides a base for further study about the optimal requirements from dietary fiber and fat for the growing Egyptian geese.

Glycerol monolaurate (GML), a medium-chain fatty acid derivative, ameliorate growth performance, immune function, disease resistance and intestinal microbiota in juvenile hybrid grouper (Epinephelus fuscoguttatus♀ × Epinephelus lanceolatus♂)

In order to evaluate the effects of glycerol monolaurate (GML) on the growth performance, immunology function, disease resistance and intestinal microbiota for hybrid groupers. Seven levels of GML (0, 600, 1200, 1800, 2400, 3000 and 3600 mg/kg) were added to diets and were noted as the G1 (control group), G2, G3, G4, G5, G6 and G7, respectively. Each experimental diet was fed to triplicate groups of 30 juvenile groupers for 8 weeks. The FBW, WGR and SGR were significantly higher and FCR was significantly lower in the G4 group compared to the G1 group (P < 0.05). Serum immune enzyme activities (ACP, AKP and LZM) rose and then fell and had the highest values in the G4 group (P < 0.05). The expression of TNF-α and IL6 in head kidney was significantly inhibited (P < 0.05), while the expression of TLR22 was increased (P < 0.05). After the Vibrio parahaemolyticus challenge test, ACP and AKP activities were increased in the G4 and G5 groups, while mortality was lower than in the G1 group (P < 0.05). GML significantly modulated the abundance of intestinal microbiota, with the G4 and G5 groups increasing the relative abundance of the Firmicutes and Bacillus, respectively (P < 0.05). The alpha diversity of the G5 group (Sob, Chao1 and ACE) was significantly higher than that of the G1 group (P < 0.05). In summary, the optimal level of GML was 1700 mg/kg according to the regression equation model fitted by the WGR index.

Inhibition of Cronobacter sakazakii in an infant simulator of the human intestinal microbial ecosystem using a potential synbiotic

Powdered infant formula (PIF) can be contaminated with Cronobacter sakazakii, which can cause severe illnesses in infants. Synbiotics, a combination of probiotics and prebiotics, could act as an alternative control measure for C. sakazakii contamination in PIF and within the infant gut, but synbiotics have not been well studied for their ability to inhibit C. sakazakii. Using a Simulator of the Human Intestinal Microbial Ecosystem (SHIME^®) inoculated with infant fecal matter, we demonstrated that a potential synbiotic, consisting of six lactic acid bacteria (LAB) strains and Vivinal GOS, can inhibit the growth of C. sakazakii in an infant possibly through either the production of antimicrobial metabolites like acetate, increasing species diversity within the SHIME compartments to compete for nutrients or a combination of mechanisms. Using a triple SHIME set-up, i.e., three identical SHIME compartments, the first SHIME (SHIME 1) was designated as the control SHIME in the absence of a treatment, whereas SHIME 2 and 3 were the treated SHIME over 2, 1-week treatment periods. The addition of the potential synbiotic (LAB + VGOS) resulted in a significant decrease in C. sakazakii levels within 1 week (p < 0.05), but in the absence of a treatment the significant decline took 2 weeks (p < 0.05), and the LAB treatment did not decrease C. sakazakii levels (p ≥ 0.05). The principal component analysis showed a distinction between metabolomic profiles for the control and LAB treatment, but similar profiles for the LAB + VGOS treatment. The addition of the potential synbiotic (LAB + VGOS) in the first treatment period slightly increased species diversity (p ≥ 0.05) compared to the control and LAB, which may have had an effect on the survival of C. sakazakii throughout the treatment period. Our results also revealed that the relative abundance of Bifidobacterium was negatively correlated with Cronobacter when no treatments were added (ρ = −0.96; p < 0.05). These findings suggest that C. sakazakii could be inhibited by the native gut microbiota, and inhibition can be accelerated by the potential synbiotic treatment.

GC- and UHPLC-MS Profiles as a Tool to Valorize the Red Alga Asparagopsis armata

Asparagopsis armata Harvey is a red alga native from the southern hemisphere and then introduced in the Mediterranean Sea and the Atlantic Ocean, including the Azores Archipelago, where it is considered an invasive alga. Some studies show that the extracts exhibit antimicrobial and antifouling activities, and it is incorporated in some commercialized cosmetic products. (e.g., Ysaline®). However, knowledge of this species chemical composition is scarce. The GC-MS and UHPLC-MS profiles of both the nonpolar and polar extracts were established to contribute to this problem solution. According to the results, A. armata is rich in a great structural variety of halogenated lipophilic and aromatic compounds, some of them identified here for the first time. In the lipophilic extract, 25 compounds are identified, being the halogenated compounds and fatty acids, the two major compound families, corresponding to 54.8% and 35.7% of identified compounds (224 and 147 mg/100 g of dry algae, respectively). The 1,4-dibromobuten-1-ol and the palmitic acid are the two most abundant identified compounds (155 and 83.4 mg/100 g of dry algae, respectively). The polar extract demonstrated the richness of this species in brominated phenolics, from which the cinnamic acid derivatives are predominant. The results obtained herein open new perspectives for valuing the A. armata as a source of halogenated compounds and fatty acids, consequently improving its biotechnological and economic potential. Promoting this seaweed and the consequent increase in its demand will contribute to biodiversity conservation and ecosystem sustainability.

Omics Strategies in Current Advancements of Infectious Fish Disease Management

Aquaculture is an important industry globally as it remains one of the significant alternatives of animal protein source supplies for humankind. Yet, the progression of this industry is being dampened by the increasing rate of fish mortality, mainly the outbreak of infectious diseases. Consequently, the regress in aquaculture ultimately results in the economy of multiple countries being affected due to the decline of product yields and marketability. By 2025, aquaculture is expected to contribute approximately 57% of fish consumption worldwide. Without a strategic approach to curb infectious diseases, the increasing demands of the aquaculture industry may not be sustainable and hence contributing to the over-fishing of wild fish. Recently, a new holistic approach that utilizes multi-omics platforms including transcriptomics, proteomics, and metabolomics is unraveling the intricate molecular mechanisms of host-pathogen interaction. This approach aims to provide a better understanding of how to improve the resistance of host species. However, no comprehensive review has been published on multi-omics strategies in deciphering fish disease etiology and molecular regulation. Most publications have only covered particular omics and no constructive reviews on various omics findings across fish species, particularly on their immune systems, have been described elsewhere. Our previous publication reviewed the integration of omics application for understanding the mechanism of fish immune response due to microbial infection. Hence, this review provides a thorough compilation of current advancements in omics strategies for fish disease management in the aquaculture industry. The discovery of biomarkers in various fish diseases and their potential advancement to complement the recent progress in combatting fish disease is also discussed in this review.

Dietary Bioactive Lipids: A Review on Absorption, Metabolism, and Health Properties

Dietary lipids are an indispensable source of energy and nutrition in human life. Numerous studies have shown that dietary bioactive lipids have many health benefits, including prevention or treatment of chronic diseases. The different chemical compositions and structural characteristics of bioactive lipids not only affect their digestion, absorption, and metabolism but also affect their health properties. In this review, the major dietary bioactive lipids (fatty acids, carotenoids, phytosterols, phenolic lipids, fat-soluble vitamins, and sphingomyelins) in foods are systematically summarized, from the aspects of composition, digestion, absorption, metabolism, source, structural characteristics, and their health properties. In particular, the relationship between the compositional and structural changes of bioactive lipids and their absorption and metabolism is discussed as well as their effect on health properties. This review provides a comprehensive summary toward health properties of dietary bioactive lipids.

The Canonical Long-Chain Fatty Acid Sensing Machinery Processes Arachidonic Acid To Inhibit Virulence in Enterohemorrhagic Escherichia coli

Polyunsaturated fatty acids (PUFAs) play important roles in host immunity. Manipulation of lipid content in host tissues through diet or pharmacological interventions is associated with altered severity of various inflammatory diseases.

The mammalian gastrointestinal tract is a complex biochemical organ that generates a diverse milieu of host- and microbe-derived metabolites. In this environment, bacterial pathogens sense and respond to specific stimuli, which are integrated into the regulation of their virulence programs. Previously, we identified the transcription factor FadR, a long-chain fatty acid (LCFA) acyl coenzyme A (acyl-CoA) sensor, as a novel virulence regulator in the human foodborne pathogen enterohemorrhagic Escherichia coli (EHEC). Here, we demonstrate that exogenous LCFAs directly inhibit the locus of enterocyte effacement (LEE) pathogenicity island in EHEC through sensing by FadR. Moreover, in addition to LCFAs that are 18 carbons in length or shorter, we introduce host-derived arachidonic acid (C_20:4) as an additional LCFA that is recognized by the FadR system in EHEC. We show that arachidonic acid is processed by the acyl-CoA synthetase FadD, which permits binding to FadR and decreases FadR affinity for its target DNA sequences. This interaction enables the transcriptional regulation of FadR-responsive operons by arachidonic acid in EHEC, including the LEE. Finally, we show that arachidonic acid inhibits hallmarks of EHEC disease in a FadR-dependent manner, including EHEC attachment to epithelial cells and the formation of attaching and effacing lesions. Together, our findings delineate a molecular mechanism demonstrating how LCFAs can directly inhibit the virulence of an enteric bacterial pathogen. More broadly, our findings expand the repertoire of ligands sensed by the canonical LFCA sensing machinery in EHEC to include arachidonic acid, an important bioactive lipid that is ubiquitous within host environments.

PhoQ is an unsaturated fatty acid receptor that fine-tunes Salmonella pathogenic traits

The Salmonella enterica PhoP/PhoQ two-component signaling system coordinates the spatiotemporal expression of key virulence factors that confer pathogenic traits. Through biochemical and structural analyses, we found that the sensor histidine kinase PhoQ acted as a receptor for long-chain unsaturated fatty acids (LCUFAs), which induced a conformational change in the periplasmic domain of the PhoQ protein. This resulted in the repression of PhoQ autokinase activity, leading to inhibition of the expression of PhoP/PhoQ-dependent genes. Recognition of the LCUFA linoleic acid (LA) by PhoQ was not stereospecific because positional and geometrical isomers of LA equally inhibited PhoQ autophosphorylation, which was conserved in multiple S. enterica serovars. Because orally acquired Salmonella encounters conjugated LA (CLA), a product of the metabolic conversion of LA by microbiota, in the human intestine, we tested how short-term oral administration of CLA affected gut colonization and systemic dissemination in a mouse model of Salmonella-induced colitis. Compared to untreated mice, CLA-treated mice showed increased gut colonization by wild-type Salmonella, as well as increased dissemination to the spleen. In contrast, the inability of the phoP strain to disseminate systemically remained unchanged by CLA treatment. Together, our results reveal that, by inhibiting PhoQ, environmental LCUFAs fine-tune the fate of Salmonella during infection. These findings may aid in the design of new anti-Salmonella therapies.

Dietary probiotic and metabolites improve intestinal homeostasis and prevent colorectal cancer

Metabolites from Lactobacillus casei display substantial antioxidant and anti-inflammatory activities, inhibit colorectal cancer cell proliferation and growth, and modulate gut microfloral composition, specifically reducing sulfidogenic bacteria.

Effect of dietary fat level and source on performance and immune system response of turkeys

An experiment was conducted to determine effects of different levels and sources of fats in diets on growth performance, carcass characteristics and immune response of turkeys during four periods (0-21, 22 to 42, 43 to 63 and 64 to 70 days of age). A completely randomized design with five treatments, six replicates and eight B.U.T.6 turkey chickens per replicate was used. Treatments included: Control diet, diet containing 2.5% of soybean oil, diet containing 2.5% fat supplement, diet containing 5% soybean oil, diet containing 5% fat supplement. The results showed that using 5% of soybean oil increased average daily gain of turkeys (89.04 g) throughout the experimental period (0-70 days) compared with the control group (81.11 g; p < 0.05). Treatments containing 2.5 and 5% soybean oil improved feed conversion ratio compared to control group (p < 0.05). Soybean oil at the levels of 2.5 and 5% was led to higher spleen and bursa percentages compared to other treatments, respectively (p < 0.05). The level and source of dietary fat had not significant effect on antibody titer against Newcastle virus vaccine on 42 and 70 days of age (p > 0.05). It can be concluded that supplementing diet with 5% soybean oil improved the performance of turkeys.

Development of Salmonellosis as Affected by Bioactive Food Compounds

Infections caused by Salmonella serovars are the leading cause of foodborne hospitalizations and deaths in Americans, extensively prevalent worldwide, and pose a considerable financial burden on public health infrastructure and private manufacturing. While a comprehensive review is lacking for delineating the role of dietary components on prevention of Salmonellosis, evidence for the role of diet for preventing the infection and management of Salmonellosis symptoms is increasing. The current study is an evaluation of preclinical and clinical studies and their underlying mechanisms to elaborate the efficacy of bioactive dietary components for augmenting the prevention of Salmonella infection. Studies investigating dietary components such as fibers, fatty acids, amino acids, vitamins, minerals, phenolic compounds, and probiotics exhibited efficacy of dietary compounds against Salmonellosis through manipulation of host bile acids, mucin, epithelial barrier, innate and adaptive immunity and gut microbiota as well as impacting the cellular signaling cascades of the pathogen. Pre-clinical studies investigating synergism and/or antagonistic activities of various bioactive compounds, additional randomized clinical trials, if not curtailed by lack of equipoise and ethical concerns, and well-planned epidemiological studies could augment the development of a validated and evidence-based guideline for mitigating the public health burden of human Salmonellosis through dietary compounds.

Metabolite profiling of Epinephelus fuscoguttatus infected with vibriosis reveals Omega 9 as potential metabolite biomarker

In this study, we report the starvation effect and vibriosis infection on a tropical fish, the tiger grouper (Epinephelus fuscoguttatus). The tiger groupers were infected with Vibrio vulnificus for 21 days. Gas chromatography-mass spectrometry combined with multivariate analysis was used to assess the variation in metabolite profiles of E. fuscoguttatus. Metabolite productions in infected fishes were significantly influenced by fatty acid production. The Omega 9 (ω-9) was abundant under the challenged conditions compared to Omega 3 (ω-3) and Omega 6 (ω-6). A total of six fatty acids from the ω-9 group were detected in high concentration in the infected fishes compared to the control groupers. These metabolites are Oleic acid, Palmitoleic acid, 6,9-Octadecenoic acid, 8,11-Eicosadienoic acid, cis-Erucic acid and 5,8,11-Eicosatrienoic acid. The production of ω-9 differed significantly (p ≤ 0.001) in the challenged samples. The detected ω-9 compounds were quantified based on three different extraction techniques with Supelco 37-component FAME mix (Supelco, USA). The highest concentration of ω-9 groups compared to the other fatty acids detected is 1320.79 mg/4 g and the lowest is 939 mg/4 g in challenged-starved; meanwhile, in challenged-fed, the highest concentration detected is 1220.87 mg/4 g and the lowest is 917.25 mg/4 g. These changes demonstrate that ω-9 can be used as a biomarker of infection in fish.

The negative effect of lipid challenge on autophagy inhibits T cell responses

Obesity is associated with changes in the immune system that significantly hinder its ability to mount efficient immune responses. Previous studies have reported a dysregulation of immune responses caused by lipid challenge; however, the mechanisms underlying that dysregulation are still not completely understood. Autophagy is an essential catabolic process through which cellular components are degraded by the lysosomal machinery. In T cells, autophagy is an actively regulated process necessary to sustain homeostasis and activation. Here, we report that CD4⁺ T cell responses are inhibited when cells are challenged with increasing concentrations of fatty acids. Furthermore, analysis of T cells from diet-induced obese mice confirms that high lipid load inhibits activation-induced responses in T cells. We have found that autophagy is inhibited in CD4⁺ T cells exposed in vitro or in vivo to lipid stress, which causes decreased autophagosome formation and degradation. Supporting that inhibition of autophagy caused by high lipid load is a key mechanism that accounts for the effects on T cell function of lipid stress, we found that ATG7 (autophagy-related 7)-deficient T cells, unable to activate autophagy, did not show additional inhibitory effects on their responses to activation when subjected to lipid challenge. Our results indicate, thus, that increased lipid load can dysregulate autophagy and cause defective T cell responses, and suggest that inhibition of autophagy may underlie some of the characteristic obesity-associated defects in the T cell compartment.Abbreviations: ACTB: actin, beta; ATG: autophagy-related; CDKN1B: cyclin-dependent kinase inhibitor 1B; HFD: high-fat diet; IFNG: interferon gamma; IL: interleukin; MAPK1/ERK2: mitogen-activated protein kinase 1; MAPK3/ERK1: mitogen-activated protein kinase 3; MAPK8/JNK: mitogen-activated protein kinase 8; LC3-I: non-conjugated form of MAP1LC3B; LC3-II: phosphatidylethanolamine-conjugated form of MAP1LC3B; MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; MS: mass spectrometry; MTOR: mechanistic target of rapamycin kinase; NFATC2: nuclear factor of activated T cells, cytoplasmic, calcineurin dependent 2; NLRP3: NLR family, pyrin domain containing 3; OA: oleic acid; PI: propidium iodide; ROS: reactive oxygen species; STAT5A: signal transducer and activator of transcription 5A; TCR: T cell receptor; T_H1: T helper cell type 1.

Sodium butyrate ameliorates Corynebacterium pseudotuberculosis infection in RAW264.7 macrophages and C57BL/6 mice

Corynebacterium pseudotuberculosis (CP) infection in livestock has become highly difficult to control. To decrease the incidence of CP infection, the supplementation of feed with non-antibiotic antibacterial substances is a potential approach. The aim of this study was to assess the effects of sodium butyrate (NaB), a potential alternative to antibiotics, on CP infection in RAW264.7 macrophages and C57BL/6 mice. Our data showed that NaB (2 mM) significantly ameliorated CPinfection in RAW264.7 macrophages and decreased the bacterial load in the spleens of infected mice. By real-time PCR, we found that NaB induced significant decreases in zinc-dependent superoxide dismutase (sodC) and tip protein C (spaC) expression in CP from infected-RAW264.7 cells and in phospholipase D (pld) and spaC expression in CP from the spleens of infected mice. NaB treatment significantly up-regulated cathelicidin-related antimicrobial peptide (cramp) expression in spleens of mice infected with CP. Furthermore, NaB alleviated histopathological changes in spleens of CP-infected mice. In conclusion, NaB ameliorated CP infection in RAW264.7 macrophages and C57BL/6 mice, and these effects may be related to the modulation of sodC, spaC, pld, and cramp expression.

Global metabolomic analysis of a mammalian host infected with Bacillus anthracis

Whereas DNA provides the information to design life and proteins provide the materials to construct it, the metabolome can be viewed as the physiology that powers it. As such, metabolomics, the field charged with the study of the dynamic small-molecule fluctuations that occur in response to changing biology, is now being used to study the basis of disease. Here, we describe a comprehensive metabolomic analysis of a systemic bacterial infection using Bacillus anthracis, the etiological agent of anthrax disease, as the model pathogen. An organ and blood analysis identified approximately 400 metabolites, including several key classes of lipids involved in inflammation, as being suppressed by B. anthracis. Metabolite changes were detected as early as 1 day postinfection, well before the onset of disease or the spread of bacteria to organs, which testifies to the sensitivity of this methodology. Functional studies using pharmacologic inhibition of host phospholipases support the idea of a role of these key enzymes and lipid mediators in host survival during anthrax disease. Finally, the results are integrated to provide a comprehensive picture of how B. anthracis alters host physiology. Collectively, the results of this study provide a blueprint for using metabolomics as a platform to identify and study novel host-pathogen interactions that shape the outcome of an infection.

Use of Caprylic Acid in Broiler Chickens: Effect on Campylobacter jejuni

The effect of caprylic acid (CA) on Campylobacter jejuni in chickens was evaluated using two approaches: dietary supplementation or surface treatment of chilled chicken carcasses. To analyze the dietary effect of CA, individually housed broiler chickens (n = 48) were artificially infected with C. jejuni VFU612 (10(6) colony-forming units [CFU]/bird) on the 21st and 35th days of life. Dietary CA (2.5 and 5 g/kg of feed, fed throughout the entire experiment) significantly decreased C. jejuni shedding (p<0.05). However, the effect only lasted for 3-7 days after infection. The numbers of Campylobacter shed by the positive control birds reached its maximum on the 37th day of life, while on that same day, both Treatment I and Treatment II groups shed significantly lower (p<0.05) numbers of Campylobacter (by 0.8 and 1.8 log10 CFU/g, respectively). Also, peak shedding was delayed by 1 day in both treated groups. After euthanasia of each chicken on the 42nd day of life, no differences in Campylobacter counts in the crop, gizzard, ileum, and cecum were found between the positive control and the treated groups (p>0.05). Surface contamination of the chilled chicken halves was performed with C. jejuni VFU612 (clinical isolate) and CCM6214 (collection strain). Surface treatment with CA at 1.25 and 2.5 mg/mL for 1 min significantly reduced C. jejuni VFU612 contamination of chicken skin (p<0.05) by 0.29-0.53 and 1.14-1.58 log10 CFU/g of skin, respectively. Counts of C. jejuni CCM6214 were reduced by 0.68-1.65 log10 CFU/g of skin). In conclusion, dietary CA affected numbers of C. jejuni in the gastrointestinal contents of chickens, whereas surface treatment reduced C. jejuni contamination in processed chicken carcasses.

Asplenioideae Species as a Reservoir of Volatile Organic Compounds with Potential Therapeutic Properties

Twelve French Asplenioideae ferns (genera Asplenium and subgenera Ceterach and Phyllitis) were investigated for the first time for volatile organic compounds (VOC) using GC-MS. Sixty-two VOC biosynthesized from the lipidic, shikimic, terpenic and carotenoid pathways were identified. Several VOC profiles can be highlighted from Asplenium jahandiezii and A.x alternifolium with exclusively lipidic derivatives to A. onopteris with an equal ratio of lipidic/shikimic compounds. Very few terpenes as caryophyllene derivatives were identified, but only in A. obovatum subsp. bilotii. The main odorous lipidic derivatives were ( E)-2-decenal (waxy and fatty odor), nonanal (aldehydic and waxy odor with a fresh green nuance), ( E)-2-heptenal (green odor with a fatty note) and 1-octen-3-ol (mushroom-like odor), reported for all species. A few VOC are present in several species in high content, i.e., 9-oxononanoic acid used as a precursor for biopolymers (19% in A. jahandiezii), 4-hydroxyacetophenone with a sweet and heavy floral odor (17.1% in A. onopteris), and 4-hydroxybenzoic acid used as a precursor in the synthesis of parabens (11.3% in A. foreziense). Most of the identified compounds have pharmacological activities, i.e., octanoic acid as antimicrobial, in particular against Salmonellas, with fatty and waxy odor (41.1% in A. petrarchae), tetradecanoic acid with trypanocidal activity (13.3% in A. obovatum subsp. bilotii), 4-hydroxybenzoic acid (8.7% in A. onopteris) with antimicrobial and anti-aging effects, 3,4-dihydroxybenzaldehyde as an inhibitor of growth of human cancer cells (6.7% in Ceterach officinarum), and phenylacetic acid with antifungal and antibacterial activities (5.8% in A. onopteris). Propionylfilicinic acid was identified in the twelve species. The broad spectrum of odorous and bioactive VOC identified from the Asplenium, Ceterach and Phyllitis species are indeed of great interest to the cosmetic and food industries.

Fatty acids, lipid mediators, and T-cell function

Research toward the mechanisms underlying obesity-linked complications has intensified during the last years. As a consequence, it has become clear that metabolism and immunity are intimately linked. Free fatty acids and other lipids acquired in excess by current feeding patterns have been proposed to mediate this link due to their immune modulatory capacity. The functional differences between saturated and unsaturated fatty acids, in combination with their dietary intake are believed to modulate the outcome of immune responses. Moreover, unsaturated fatty acids can be oxidized in a tightly regulated and specific manner to generate either potent pro-inflammatory or pro-resolving lipid mediators. These oxidative derivatives of fatty acids have received detailed attention during the last years, as they have proven to have strong immune modulatory capacity, even in pM ranges. Both fatty acids and oxidized fatty acids have been studied especially in relation to macrophage and T-cells functions. In this review, we propose to focus on the effect of fatty acids and their oxidative derivatives on T-cells, as it is an active area of research during the past 5 years. The effect of fatty acids and their derivatives on activation and proliferation of T-cells, as well as the delicate balance between stimulation and lipotoxicity will be discussed. Moreover, the receptors involved in the interaction between free fatty acids and their derivatives with T-cells will be summarized. Finally, the mechanisms involved in modulation of T-cells by fatty acids will be addressed, including cellular signaling and metabolism of T-cells. The in vitro results will be placed in context of in vivo studies both in humans and mice. In this review, we summarize the latest findings on the immune modulatory function of lipids on T-cells and will point out novel directions for future research.

Lipophilic profile of the edible halophyte Salicornia ramosissima

Salicornia ramosissima J. Woods is considered, in the Iberian Peninsula and France, a gourmet product. Nevertheless, is one of the less studied Salicornia species. In this work, GC-MS was employed to, for the first time; fully characterise the lipophilic profile of S. ramosissima and to assess the effect of natural and extra irrigation in that profile. The obtained data showed esterified and free fatty acids, fatty alcohol, sterols, alkanes and aromatic acid derivatives, being palmitic acid, tetracosanol and octacosanol the most abundant compounds. The extra irrigation increases significantly (P<0.001) the content of esterified lipophilic compounds. Stigmastanol, 24-ethyl-δ(22)-coprostenol, several secondary fatty alcohols and dicarboxylic acids were identified for the first time in Salicornia genus. Several of the detected compounds are known to have health benefits and our results suggest that S. ramosissima should be considered as an important dietary source of lipophilic phytochemicals.