Non-digestible oligosaccharides partially prevent the development of LPS-induced lung emphysema in mice

Effects of nondigestible oligosaccharides on inflammation, lung health, and performance of calves

Our objective was to determine the effects of nondigestible oligosaccharides (NDO) on lung health and performance. Three hundred male Holstein-Friesian calves aged 18.0 ± 3.6 d received 1 of 6 treatments for 8.5 wk (period 1). Treatments included a negative control (CON), galacto-oligosaccharides (GOS) administered as a spray via the nose once daily (SPR), GOS administered via the milk replacer (MR) at 1% (GOS-L) and 2% (GOS-H), fructo-oligosaccharides administered via the MR at 0.25% (FOS) and a combination of GOS and fructo-oligosaccharides administered via the MR at 1% and 0.25%, respectively (GOS-FOS). Milk replacer was fed twice daily. Feeding levels were equal between calves and increased progressively in time. Body weight was measured every 4 wk and clinical health was scored weekly. Blood and broncho-alveolar lavage fluid (BALF) samples were collected bi-weekly from a subset of calves (n = 120). After period 1, all calves received the same control MR for 18 wk until slaughter (period 2), during which general performance and clinical health were measured. Generally, infection pressure was high, with clinical scores and BALF proinflammatory TNFα concentrations increasing with time in period 1, which resulted in a high number of required group antimicrobial treatments (6 group antimicrobial treatments in 13 wk, supplied to all calves). Average daily gain adjusted to equal solid feed intake was increased for GOS-L (+61 g/d) compared with CON calves from experimental wk 1 to 5. Plasma white blood cell concentration tended to be lowered by GOS-L, plasma IL-8 concentration was reduced by all orally supplemented NDO, plasma IL-6 was reduced by all NDO treatments except GOS-FOS and plasma IL-1β was reduced by all NDO treatments compared with CON, although this differed per time point for SPR. The neutrophil percentage in BALF was reduced by GOS-L in wk 6, which was associated with a relative increase in macrophages. The BALF concentration of TNFα and IL-8 was reduced or tended to be reduced by GOS-L and GOS-H, while IL-6 was or tended to be reduced by SPR, GOS-L, GOS-H, and GOS-FOS, and IL-1β was reduced by SPR, GOS-L, GOS-H, and FOS. Generally, feeding the combination of GOS and FOS was not more effective than feeding GOS or FOS alone, because feeding GOS-FOS resulted in higher concentrations of plasma and BALF cytokine and chemokine concentrations compared with feeding GOS-L alone, and resulted in higher plasma cytokine concentrations compared with feeding FOS alone. None of the BALF and plasma cytokine or chemokine concentrations differed between the GOS-L and GOS-H treatment. Performance and clinical scores in period 2 did not differ among treatments. Altogether, all tested NDO reduced systemic and lung inflammation in calves under high natural infection pressure and for GOS-fed calves, this increased performance during the first 4 wk. Combining GOS and FOS did not have a synergistic effect. The intranasal administration of GOS also lowered systemic and lung inflammation, but tended to negatively affect performance. Overall, this study demonstrates the potential of NDO to alleviate systemic and respiratory inflammation in calves.

In vitro and in vivo protective potential of quercetin-3-glucuronide against lipopolysaccharide-induced pulmonary injury through dual activation of nuclear factor-erythroid 2 related factor 2 and autophagy

In vitro and in vivo models of lipopolysaccharide (LPS)-induced pulmonary injury, quercetin-3-glucuronide (Q3G) has been previously revealed the lung-protective potential via downregulation of inflammation, pyroptotic, and apoptotic cell death. However, the upstream signals mediating anti-pulmonary injury of Q3G have not yet been clarified. It has been reported that concerted dual activation of nuclear factor-erythroid 2 related factor 2 (Nrf2) and autophagy may prove to be a better treatment strategy in pulmonary injury. In this study, the effect of Q3G on antioxidant and autophagy were further investigated. Noncytotoxic doses of Q3G abolished the LPS-caused cell injury, and reactive oxygen species (ROS) generation with inductions in Nrf2-antioxidant signaling. Moreover, Q3G treatment repressed Nrf2 ubiquitination, and enhanced the association of Keap1 and p62 in the LPS-treated cells. Q3G also showed potential in inducing autophagy, as demonstrated by formation of acidic vesicular organelles (AVOs) and upregulation of autophagy factors. Next, the autolysosomes formation and cell survival were decreased by Q3G under pre-treatment with a lysosome inhibitor, chloroquine (CQ). Furthermore, mechanistic assays indicated that anti-pulmonary injury effects of Q3G might be mediated via Nrf2 signaling, as confirmed by the transfection of Nrf2 siRNA. Finally, Q3G significantly alleviated the development of pulmonary injury in vivo, which may result from inhibiting the LPS-induced lung dysfunction and edema. These findings emphasize a toxicological perspective, providing new insights into the mechanisms of Q3G's protective effects on LPS-induced pulmonary injury and highlighting its role in dual activating Nrf2 and autophagy pathways.

Non-Digestible Oligosaccharides: A Novel Treatment for Respiratory Infections?

Emerging antimicrobial resistance in respiratory infections requires novel intervention strategies. Non-digestible oligosaccharides (NDOs) are a diverse group of carbohydrates with broad protective effects. In addition to promoting the colonization of beneficial gut microbiota and maintaining the intestinal homeostasis, NDOs act as decoy receptors, effectively blocking the attachment of pathogens on host cells. NDOs also function as a bacteriostatic agent, inhibiting the growth of specific pathogenic bacteria. Based on this fact, NDOs potentiate the actions of antimicrobial drugs. Therefore, there is an increasing interest in characterizing the anti-infective properties of NDOs. This focused review provides insights into the mechanisms by which representative NDOs may suppress respiratory infections by targeting pathogens and host cells. We summarized the most interesting mechanisms of NDOs, including maintenance of gut microbiota homeostasis, interference with TLR-mediated signaling, anti-oxidative effects and bacterial toxin neutralization, bacteriostatic and bactericidal effects, and anti-adhesion or anti-invasive properties. A detailed understanding of anti-infective mechanisms of NDOs against respiratory pathogens may contribute to the development of add-on therapy or alternatives to antimicrobials.

Effect of targeted nutrient supplementation on physical activity and health-related quality of life in COPD: study protocol for the randomised controlled NUTRECOVER trial

INTRODUCTION

Physical and mental health are often affected in chronic obstructive pulmonary disease (COPD) adversely affecting disease course and quality of life. Abnormalities in whole body and cellular energy metabolism, dietary and plasma nutrient status and intestinal permeability have been well established in these patients as systemic determinants of functional decline and underexplored treatable traits. The aim of this study is to investigate the efficacy of 1 year targeted nutrient supplementation on physical activity level and health-related quality of life in patients with COPD.

METHODS AND ANALYSIS

This study is a single-centre randomised, placebo-controlled, double-blind trial in 166 patients with COPD recruited from multiple hospitals in the Netherlands. The intervention group will receive a multinutrient supplement, including vitamin D, tryptophan, long-chain polyunsaturated fatty acids and prebiotic dietary fibres as main components (94 kCal per daily dose). The control group will receive an isocaloric isonitrogenous placebo. Both groups will ingest one portion per day for at least 12 months and will additionally receive counselling on healthy lifestyle and medical adherence over the course of the study. Coprimary outcomes are physical activity assessed by triaxial accelerometry and health-related quality of life measured by the EuroQol-5 dimensions questionnaire. Secondary outcomes are cognitive function, psychological well-being, physical performance, patient-reported outcomes and the metabolic profile assessed by body composition, systemic inflammation, plasma nutrient levels, intestinal integrity and microbiome composition. Outcomes will be measured at baseline and after 12 months of supplementation. In case patients are hospitalised for a COPD exacerbation, a subset outcome panel will be measured during a 4-week recovery period after hospitalisation.

ETHICS AND DISSEMINATION

This study was approved by the local Ethics Committee of Maastricht University. Subjects will be included after written informed consent is provided. Study outcomes will be disseminated through presentations at (inter)national conferences and through peer-reviewed journals.

TRIAL REGISTRATION

NCT03807310.

Galacto-oligosaccharides alleviate lung inflammation by inhibiting NLRP3 inflammasome activation in vivo and in vitro

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GOS suppress both local and systemic inflammation in lung infections.

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GOS reduce the M. haemolytica positivity in calves with lung infections.

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GOS inhibit NLRP3 inflammasome activation in vivo and in vitro.

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GOS decrease ATP production in PBECs induced by M. haemolytica.

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Direct anti-oxidative effects of GOS on lung cells are involved.

Introduction

Objectives

Methods

Results

Conclusion

Anti-Inflammatory Properties of Fructo-Oligosaccharides in a Calf Lung Infection Model and in Mannheimia haemolytica-Infected Airway Epithelial Cells

Emerging antimicrobial-resistant pathogens highlight the importance of developing novel interventions. Here, we investigated the anti-inflammatory properties of Fructo-oligosaccharides (FOS) in calf lung infections and in airway epithelial cells stimulated with pathogens, and/or bacterial components. During a natural exposure, 100 male calves were fed milk replacer with or without FOS for 8 weeks. Then, immune parameters and cytokine/chemokine levels in the bronchoalveolar lavage fluid (BALF) and blood were measured, and clinical scores were investigated. Calf primary bronchial epithelial cells (PBECs) and human airway epithelial cells (A549) were treated with Mannheimia haemolytica, lipopolysaccharides (LPS), and/or flagellin, with or without FOS pretreatment. Thereafter, the cytokine/chemokine levels and epithelial barrier function were examined. Relative to the control (naturally occurring lung infections), FOS-fed calves had greater macrophage numbers in BALF and lower interleukin (IL)-8, IL-6, and IL-1β concentrations in the BALF and blood. However, FOS did not affect the clinical scores. At slaughter, FOS-fed calves had a lower severity of lung lesions compared to the control. Ex vivo, FOS prevented M. haemolytica-induced epithelial barrier dysfunction. Moreover, FOS reduced M. haemolytica- and flagellin-induced (but not LPS-induced) IL-8, TNF-α, and IL-6 release in PBECs and A549 cells. Overall, FOS had anti-inflammatory properties during the natural incidence of lung infections but had no effects on clinical symptoms.

Isomalto-Oligosaccharides Produced by EndodextranaseShewanellasp. GZ-7 From Sugarcane Plants

Oligosaccharides have important alimental and medical applications. Dextranase has been used to produce isomalto-oligosaccharides (IMOs). In this study, we isolated dextranase-producing bacteria from sugarcane-cultivated soil. Identification of the isolate based on its phenotypical, physiological, and biochemical characteristics, as well as 16S ribosomal deoxyribonucleic acid gene sequencing yielded Shewanella sp. strain GZ-7. The molecular weight of the dextranase produced by this strain was 100-135 kDa. The optimum temperature and pH for dextranase production were 40 °C and 7.5, respectively. The enzyme was found to be stable at the pH range of 6.0-8.0 and the temperature range of 20 °C-40 °C. Thin-layer chromatography and high-performance liquid chromatography of the enzymolysis products of the substrate confirmed the enzyme to be endodextranase. Under the optimal conditions, the ratio of IMOs could reach 91.8% of the hydrolyzate. The final products were found to efficiently scavenge the 2,2-diphenyl-1-picrylhydrazyl, hydroxyl, and superoxide anion radicals. In general, dextranase and hydrolyzates have high potential prospects for application in the future.