scholarly journals Development of an Affordable, Sustainable and Efficacious Plant-Based Immunomodulatory Food Ingredient Based on Bell Pepper or Carrot RG-I Pectic Polysaccharides

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 963
Author(s):  
Sue McKay ◽  
Paul Oranje ◽  
Jari Helin ◽  
Jean H. Koek ◽  
Ellen Kreijveld ◽  
...  

The prevalence of acute respiratory infections and their impact on quality of life underlies the need for efficacious solutions that are safe, sustainable and economically viable. Polysaccharides in several (traditional) plant extracts have been shown to be immunostimulatory, and some studies suggest beneficial effects against respiratory infections. The aim of this study was to (i) identify the active polysaccharide constituents from affordable and renewable crops (bell pepper and carrot) using activity-guided fractionation, (ii) evaluate in vitro effects on innate immune responses (phagocytosis and cytokine secretion), microbiota modulation and production of short chain fatty acids, followed by (iii) the evaluation of effects of a bell pepper extract enriched for the active component in a human proof of concept study. We identified rhamnogalacturonan-I (RG-I) as the nutricophore responsible for the immunostimulatory activity with substantial structural and functional equivalence between bell pepper (bp) and carrot (c). The in vitro studies showed that bpRG-I and cRG-I comprise similar immune- and microbiota modulatory potential and the human study demonstrated that bpRG-I was well tolerated and enhanced innate immune responsiveness in vivo. This is an important step towards testing the efficacy of RG-I from bpRG-I or cRG-I in an infection trial in humans.

2016 ◽  
Author(s):  
Jeffrey M. Flynn ◽  
David Niccum ◽  
Jordan M. Dunitz ◽  
Ryan C. Hunter

Chronic respiratory infections are composed of complex microbial communities that incite persistent inflammation and airway damage. Despite the high density of bacteria that colonize the airways, nutrient sources that sustain bacterial growth in vivo are unknown. Here we examine the role of respiratory mucins in the ecological dynamics of the cystic fibrosis lung microbiota. While P. aeruginosa was unable to efficiently utilize mucins, saliva-derived anaerobes stimulated the growth of opportunistic pathogens when provided mucins as the sole carbon source. The fermentative metabolisms of these oral anaerobes generated amino acids and short chain fatty acids (propionate and acetate) during mucin enrichment in vitro, which were also found within expectorated sputum from CF patients. The significance of these findings was supported by in vivo P. aeruginosa gene expression, which revealed a heightened response to propionate. Given that propionate is exclusively derived from bacterial fermentation, these data support a central role for mucin fermentation in the carbon flux of the lower airways. More specifically, commensal oral bacteria may contribute to airway disease by degrading mucins, in turn providing nutrients for pathogens otherwise unable to obtain carbon in the lung.


Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 92-OR ◽  
Author(s):  
WEI HUANG ◽  
YONG XU ◽  
YOUHUA XU ◽  
LUPING ZHOU ◽  
CHENLIN GAO

2020 ◽  
Vol 44 (1) ◽  
Author(s):  
Oluwatosin Bode Omotoso ◽  
Mary Oluwafunmilayo Adeduntan ◽  
Adebowale Noah Fajemisin

Abstract Background The study highlighted the potential of three common and under-utilized tropical leguminous seeds (Tomentosa nilotica, Dioclea reflexa and Monodora myristica) to be used as supplementary feed to ruminant livestock. These seeds (their plants inclusive) are valuable sources of food and medicine for the prevention of illness and maintenance of human health. The medicinal properties of these seeds include antimicrobial, anti-inflammatory, anti-oxidant and immuno-stimulant. Trypsin inhibitors, which are common anti-nutritional factors in legumes and for monogastric animals, do not exert adverse effects in ruminants because they are degraded in the rumen. Hence, the crux of this study is to examine the effect of processing methods on the nutritional composition (proximate, fibre fractions, minerals, anti-nutrients) and in vitro digestibility of Tomentosa nilotica, Dioclea reflexa and Monodora myristica seeds and their suitability as feedstuff (protein sources) in small ruminant feed, particularly during off-season. Results From the results, raw Tomentosa nilotica and Monodora myristica have the highest crude protein (30.35% CP) and fat (22.40% EE), respectively. It is noteworthy that roasting best improve the mineral and significantly reduce the anti-nutrients observed in this study better compared to boiling and soaking methods. The highest organic matter digestibility, short-chain fatty acids, metabolizable energy and in vitro dry matter digestibility values were obtained in Dioclea reflexa compared to other test seeds. Roasting best improved the nutritive values, while Dioclea reflexa seed was rated highest for all the nutritional attributes and in vitro digestibility. Conclusions Dioclea reflexa could be incorporated in ruminants’ diet as protein source, particularly during the off-season, for improved ruminant production in Nigeria. However, in vivo study is therefore recommended to validate this report.


Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Shasha Xiang ◽  
Kun Ye ◽  
Mian Li ◽  
Jian Ying ◽  
Huanhuan Wang ◽  
...  

Abstract Background Xylitol, a white or transparent polyol or sugar alcohol, is digestible by colonic microorganisms and promotes the proliferation of beneficial bacteria and the production of short-chain fatty acids (SCFAs), but the mechanism underlying these effects remains unknown. We studied mice fed with 0%, 2% (2.17 g/kg/day), or 5% (5.42 g/kg/day) (weight/weight) xylitol in their chow for 3 months. In addition to the in vivo digestion experiments in mice, 3% (weight/volume) (0.27 g/kg/day for a human being) xylitol was added to a colon simulation system (CDMN) for 7 days. We performed 16S rRNA sequencing, beneficial metabolism biomarker quantification, metabolome, and metatranscriptome analyses to investigate the prebiotic mechanism of xylitol. The representative bacteria related to xylitol digestion were selected for single cultivation and co-culture of two and three bacteria to explore the microbial digestion and utilization of xylitol in media with glucose, xylitol, mixed carbon sources, or no-carbon sources. Besides, the mechanisms underlying the shift in the microbial composition and SCFAs were explored in molecular contexts. Results In both in vivo and in vitro experiments, we found that xylitol did not significantly influence the structure of the gut microbiome. However, it increased all SCFAs, especially propionate in the lumen and butyrate in the mucosa, with a shift in its corresponding bacteria in vitro. Cross-feeding, a relationship in which one organism consumes metabolites excreted by the other, was observed among Lactobacillus reuteri, Bacteroides fragilis, and Escherichia coli in the utilization of xylitol. At the molecular level, we revealed that xylitol dehydrogenase (EC 1.1.1.14), xylulokinase (EC 2.7.1.17), and xylulose phosphate isomerase (EC 5.1.3.1) were key enzymes in xylitol metabolism and were present in Bacteroides and Lachnospiraceae. Therefore, they are considered keystone bacteria in xylitol digestion. Also, xylitol affected the metabolic pathway of propionate, significantly promoting the transcription of phosphate acetyltransferase (EC 2.3.1.8) in Bifidobacterium and increasing the production of propionate. Conclusions Our results revealed that those key enzymes for xylitol digestion from different bacteria can together support the growth of micro-ecology, but they also enhanced the concentration of propionate, which lowered pH to restrict relative amounts of Escherichia and Staphylococcus. Based on the cross-feeding and competition among those bacteria, xylitol can dynamically balance proportions of the gut microbiome to promote enzymes related to xylitol metabolism and SCFAs.


2016 ◽  
Vol 85 (3) ◽  
Author(s):  
Luis A. Vega ◽  
Kayla M. Valdes ◽  
Ganesh S. Sundar ◽  
Ashton T. Belew ◽  
Emrul Islam ◽  
...  

ABSTRACTAs an exclusively human pathogen,Streptococcus pyogenes(the group A streptococcus [GAS]) has specifically adapted to evade host innate immunity and survive in multiple tissue niches, including blood. GAS can overcome the metabolic constraints of the blood environment and expresses various immunomodulatory factors necessary for survival and immune cell resistance. Here we present our investigation of one such factor, the predicted LysR family transcriptional regulator CpsY. The encoding gene,cpsY, was initially identified as being required for GAS survival in a transposon-site hybridization (TraSH) screen in whole human blood. CpsY is homologous with transcriptional regulators ofStreptococcus mutans(MetR),Streptococcus iniae(CpsY), andStreptococcus agalactiae(MtaR) that regulate methionine transport, amino acid metabolism, resistance to neutrophil-mediated killing, and survivalin vivo. Our investigation indicated that CpsY is involved in GAS resistance to innate immune cells of its human host. However, GAS CpsY does not manifest thein vitrophenotypes of its homologs in other streptococcal species. GAS CpsY appears to regulate a small set of genes that is markedly different from the regulons of its homologs. The differential expression of these genes depends on the growth medium, and CpsY modestly influences their expression. The GAS CpsY regulon includes known virulence factors (mntE,speB,spd,nga[spn],prtS[SpyCEP], andsse) and cell surface-associated factors of GAS (emm1,mur1.2,sibA[cdhA], andM5005_Spy0500). Intriguingly, the loss of CpsY in GAS does not result in virulence defects in murine models of infection, suggesting that CpsY function in immune evasion is specific to the human host.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi104-vi105
Author(s):  
Akanksha Mahajan ◽  
Lisa Hurley ◽  
Serena Tommasini-Ghelfi ◽  
Corey Dussold ◽  
Alexander Stegh ◽  
...  

Abstract The Stimulator of Interferon Genes (STING) pathway represents a major innate immune sensing mechanism for tumor-derived DNA. Modified cyclic dinucleotides (CDNs) that mimic the endogenous STING ligand cGAMP are currently being explored in patients with solid tumors that are amenable to intratumoral delivery. Inadequate bioavailability and insufficient lipophilicity are limiting factors for clinical CDN development, in particular when consideration is given to systemic administration approaches. We have shown that the formulation of oligonucleotides into Spherical Nucleic Acid (SNA) nanostructures, i.e.,the presentation of oligonucleotides at high density on the surface of nanoparticle cores, lead to biochemical and biological properties that are radically different from those of linear oligonucleotides. First-generation brain-penetrant siRNA-based SNAs (NCT03020017, recurrent GBM) have recently completed early clinical trials. Here, we report the development of a STING-agonistic immunotherapy by targeting cGAS, the sensor of cytosolic dsDNA upstream of STING, with SNAs presenting dsDNA at high surface density. The strategy of using SNAs exploits the ability of cGAS to raise STING responses by delivering dsDNA and inducing the catalytic production of endogenous CDNs. SNA nanostructures carrying a 45bp IFN-simulating dsDNA oligonucleotide, the most commonly used and widely characterized cGAS activator, potently activated the cGAS-STING pathway in vitro and in vivo. In a poorly immunogenic and highly aggressive syngeneic mouse glioma model, in which tumours were well-established, only one dose of intranasal treatment with STING-SNAs decelerated tumour growth, improved survival and importantly, was well-tolerated. Our use of SNAs addresses the challenges of nucleic acid delivery to intracranial tumor sites via intranasal route, exploits the binding of dsDNA molecules on the SNA surface to enhance the formation of a dimeric cGAS:DNA complex and establishes cGAS-agonistic SNAs as a novel class of immune-stimulatory modalities for triggering innate immune responses against tumor.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Maria Pujantell ◽  
Roger Badia ◽  
Iván Galván-Femenía ◽  
Edurne Garcia-Vidal ◽  
Rafael de Cid ◽  
...  

AbstractInfection by human papillomavirus (HPV) alters the microenvironment of keratinocytes as a mechanism to evade the immune system. A-to-I editing by ADAR1 has been reported to regulate innate immunity in response to viral infections. Here, we evaluated the role of ADAR1 in HPV infection in vitro and in vivo. Innate immune activation was characterized in human keratinocyte cell lines constitutively infected or not with HPV. ADAR1 knockdown induced an innate immune response through enhanced expression of RIG-I-like receptors (RLR) signaling cascade, over-production of type-I IFNs and pro-inflammatory cytokines. ADAR1 knockdown enhanced expression of HPV proteins, a process dependent on innate immune function as no A-to-I editing could be identified in HPV transcripts. A genetic association study was performed in a cohort of HPV/HIV infected individuals followed for a median of 6 years (range 0.1–24). We identified the low frequency haplotype AACCAT significantly associated with recurrent HPV dysplasia, suggesting a role of ADAR1 in the outcome of HPV infection in HIV+ individuals. In summary, our results suggest that ADAR1-mediated innate immune activation may influence HPV disease outcome, therefore indicating that modification of innate immune effectors regulated by ADAR1 could be a therapeutic strategy against HPV infection.


2021 ◽  
Vol 12 ◽  
Author(s):  
Anne-Gaëlle Leroy ◽  
Jocelyne Caillon ◽  
Nathalie Caroff ◽  
Alexis Broquet ◽  
Stéphane Corvec ◽  
...  

Azithromycin (AZM) is a 15-membered-ring macrolide that presents a broad-spectrum antimicrobial activity against Gram-positive bacteria and atypical microorganisms but suffers from a poor diffusion across the outer-membrane of Gram-negative bacilli, including Pseudomonas aeruginosa (PA). However, AZM has demonstrated clinical benefits in patients suffering from chronic PA respiratory infections, especially cystic fibrosis patients. Since the rise of multidrug-resistant PA has led to a growing need for new therapeutic options, this macrolide has been proposed as an adjunctive therapy. Clinical trials assessing AZM in PA acute pneumonia are scarce. However, a careful examination of the available literature provides good rationales for its use in that context. In fact, 14- and 15-membered-ring macrolides have demonstrated immunomodulatory and immunosuppressive effects that could be of major interest in the management of acute illness. Furthermore, growing evidence supports a downregulation of PA virulence dependent on direct interaction with the ribosomes, and based on the modulation of several key regulators from the Quorum Sensing network. First highlighted in vitro, these interesting properties of AZM have subsequently been confirmed in the animal models. In this review, we systematically analyzed the literature regarding AZM immunomodulatory and anti-PA effects. In vitro and in vivo studies, as well as clinical trials were reviewed, looking for rationales for AZM use in PA acute pneumonia.


PLoS ONE ◽  
2015 ◽  
Vol 10 (3) ◽  
pp. e0122774 ◽  
Author(s):  
Igor Sokolov ◽  
Natali V. Guz ◽  
Swaminathan Iyer ◽  
Amy Hewitt ◽  
Nina A. Sokolov ◽  
...  

2013 ◽  
Vol 81 (10) ◽  
pp. 3855-3864 ◽  
Author(s):  
Amir I. Tukhvatulin ◽  
Ilya I. Gitlin ◽  
Dmitry V. Shcheblyakov ◽  
Natalia M. Artemicheva ◽  
Lyudmila G. Burdelya ◽  
...  

ABSTRACTPathogen recognition receptors (PRRs) are essential components of host innate immune systems that detect specific conserved pathogen-associated molecular patterns (PAMPs) presented by microorganisms. Members of two families of PRRs, transmembrane Toll-like receptors (TLRs 1, 2, 4, 5, and 6) and cytosolic NOD receptors (NOD1 and NOD2), are stimulated upon recognition of various bacterial PAMPs. Such stimulation leads to induction of a number of immune defense reactions, mainly triggered via activation of the transcription factor NF-κB. While coordination of responses initiated via different PRRs sensing multiple PAMPS present during an infection makes clear biological sense for the host, such interactions have not been fully characterized. Here, we demonstrate that combined stimulation of NOD1 and TLR5 (as well as other NOD and TLR family members) strongly potentiates activity of NF-κB and induces enhanced levels of innate immune reactions (e.g., cytokine production) bothin vitroandin vivo. Moreover, we show that an increased level of NF-κB activity plays a critical role in formation of downstream responses. In live mice, synergy between these receptors resulting in potentiation of NF-κB activity was organ specific, being most prominent in the gastrointestinal tract. Coordinated activity of NOD1 and TLR5 significantly increased protection of mice against enteroinvasiveSalmonellainfection. Obtained results suggest that cooperation of NOD and TLR receptors is important for effective responses to microbial infectionin vivo.


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