Nurlan Dauletbaev

Combined effect of dietary supplementation with pressurized whey and exercise training in chronic obstructive pulmonary disease: a randomized, controlled, double-blind pilot study.

Pressurized whey supplementation, by its antioxidant and nutritional properties, may improve exercise tolerance and potentiate the effects of exercise training in patients with chronic obstructive pulmonary disease (COPD). In this randomized, double-blind, placebo-controlled study, 22 patients with COPD were allocated to receive active pressurized whey or placebo (casein) dietary supplementation for a 16-week period. Patients continued their usual physical activities for the first 8 weeks, whereas they were subjected to an exercise training program for the remaining 8 weeks of the study. Patients were evaluated at baseline, after 8 weeks of supplementation alone (time point, 8 weeks), and after 8 weeks of its combination with exercise training (time point, 16 weeks). The constant workrate cycle endurance test (CET), potentiated quadriceps twitch force, mid-thigh cross-sectional area, and Chronic Respiratory Questionnaire (CRQ) were used to evaluate the effects of treatments. The inflammatory (C-reactive protein and interleukin-6) and oxidant/antioxidant (protein oxidation and glutathione) blood profiles were also characterized. At week 8, there was no increase in CET time in either group. At week 16, there was a statistically significant increase in CET time in the whey-only group (P < .05). Further, at week 16, there was clinically significant improvement in the Dyspnea and the Mastery scales of the CRQ in both groups. Also, the Fatigue and Emotional Control scales of the CRQ showed clinically significant improvement in the whey-only group. Study interventions did not modify significantly the systemic inflammatory and oxidative stress markers that were assessed. Thus dietary supplementation with pressurized whey may potentiate the effects of exercise training on exercise tolerance and quality of life in patients with COPD.

Whey protein hydrolysates decrease IL-8 secretion in lipopolysaccharide (LPS)-stimulated respiratory epithelial cells by affecting LPS binding to Toll-like receptor 4

UNLABELLED Whey proteins (WP) exert anti-inflammatory and antioxidant effects. Hyperbaric pressurisation of whey increases its digestibility and changes the spectrum of peptides released during digestion. We have shown that dietary supplementation with pressurised whey improves nutritional status and systemic inflammation in patients with cystic fibrosis (CF). Both clinical indices are largely affected by airway processes, to which respiratory epithelial cells actively contribute. Here, we tested whether peptides released from the digestion of pressurised whey can attenuate the inflammatory responses of CF respiratory epithelial cells. Hydrolysates of pressurised WP (pWP) and native WP (nWP, control) were generated in vitro and tested for anti-inflammatory properties judged by the suppression of IL-8 production in CF and non-CF respiratory epithelial cell lines (CFTE29o- and 1HAEo-, respectively). We observed that, in both cell lines, pWP hydrolysate suppressed IL-8 production stimulated by lipopolysaccharide (LPS) to a greater magnitude compared with nWP hydrolysate. Neither hydrolysate suppressed IL-8 production induced by TNF-α or IL-1β, suggesting an effect on the Toll-like receptor (TLR) 4 pathway, the cellular sensor for LPS. Further, neither hydrolysate affected TLR4 expression or neutralised LPS. Both pWP and nWP hydrolysates similarly reduced LPS binding to surface TLR4, while pWP tended to more potently increase extracellular antioxidant capacity. IN CONCLUSION (1) anti-inflammatory properties of whey are enhanced by pressurisation; (2) suppression of IL-8 production may contribute to the clinical effects of pressurised whey supplementation on CF; (3) this effect may be partly explained by a combination of reduced LPS binding to TLR4 and enhanced extracellular antioxidant capacity.

Down-regulation of cytokine-induced interleukin-8 requires inhibition of p38 mitogen-activated protein kinase (MAPK) via MAPK phosphatase 1 dependent and independent mechanisms

Down-regulation of overabundant interleukin (IL)-8 present in cystic fibrosis (CF) airways could ease excessive neutrophil burden and its deleterious consequences for the lung. IL-8 production in airway epithelial cells, stimulated with e.g. inflammatory cytokines IL-1β and tumor necrosis factor (TNF)-α, is regulated by several signaling pathways including nuclear factor (NF)-κB and p38 mitogen-activated protein kinase (MAPK). We previously demonstrated that the anti-inflammatory drugs dexamethasone and ibuprofen suppress NF-κB; however, only dexamethasone down-regulates cytokine-induced IL-8, highlighting the importance of non-NF-κB mechanisms. Here, we tested the hypothesis that down-regulation of cytokine-induced IL-8 requires modulation of the MAPK phosphatase (MKP)-1/p38 MAPK/mRNA stability pathway. The effects of dexamethasone (5 nm) and ibuprofen (480 μm) on this pathway and IL-8 were studied in CF (CFTE29o−, CFBE41o−) and non-CF (1HAEo−) airway epithelial cells. We observed that dexamethasone, but not ibuprofen, destabilizes IL-8 mRNA and up-regulates MKP-1 mRNA. Further, siRNA silencing of MKP-1, via p38 MAPK, leads to IL-8 overproduction and diminishes the anti-IL-8 potential of dexamethasone. However, MKP-1 overexpression does not significantly alter IL-8 production. By contrast, direct inhibition of p38 MAPK (inhibitor SB203580) efficiently suppresses IL-8 with potency comparable with dexamethasone. Similar to dexamethasone, SB203580 decreases IL-8 mRNA stability. Dexamethasone does not affect p38 MAPK activation, which excludes its effects upstream of p38 MAPK. In conclusion, normal levels of MKP-1 are necessary for a full anti-IL-8 potential of pharmacological agents; however, efficient pharmacological down-regulation of cytokine-induced IL-8 also requires direct effects on p38 MAPK and mRNA stability independently of MKP-1.

Ibuprofen Modulates NF-ĸB Activity but Not IL-8 Production in Cystic Fibrosis Respiratory Epithelial Cells

Background: High-dose ibuprofen is clinically effective in cystic fibrosis (CF); however, its molecular mechanisms are poorly understood. Objective: To test the hypothesis that clinically relevant concentrations of ibuprofen suppress activation of nuclear factor (NF)-ĸB and thus down-regulate stimulated interleukin (IL)-8 production in CF respiratory epithelial cells. Methods: The majority of experiments were conducted in CFTE29o– cells (F508del-mutated CF transmembrane regulator, CFTR). Key experiments were confirmed in CFBE41o– cells (F508del-mutated CFTR) and 1HAEo– cells (wild-type CFTR). NF-ĸB and IL-8 were stimulated with tumour necrosis factor (TNF)-α or IL-1β. NF-ĸB and IL-8 suppression by ibuprofen (480 µM) was compared to dexamethasone (5 nM). Results: Both TNF-α and IL-1β activated NF-ĸB and stimulated IL-8 production. Both ibuprofen and dexamethasone demonstrated comparably modest suppression of NF-ĸB transcriptional activity. However, ibuprofen had no effect on stimulated IL-8 mRNA and protein. By contrast, dexamethasone significantly down-regulated stimulated IL-8 mRNA and protein. Conclusions: The present data do not support the hypothesis that ibuprofen down-regulates IL-8 production in response to TNF-α and IL-1β in CF respiratory epithelium. Suppression of NF-ĸB transcriptional activity does not discriminate between anti-inflammatory drugs with or without effects on IL-8 production. We speculate that NF-ĸB-independent mechanisms may be responsible for anti-IL-8 effects of dexamethasone.

Vitamin D as an anti-microbial and anti-inflammatory therapy for Cystic Fibrosis.

Cystic fibrosis (CF) is characterized by chronic infection and inflammation in the airways that lead to progressive lung damage and early death. Current anti-inflammatory therapies are limited by extensive adverse effects or insufficient efficacy. There is a large body of studies indicating beneficial anti-microbial and anti-inflammatory properties of vitamin D. Since most patients with CF present with vitamin D deficiency, and serum vitamin D levels demonstrate a positive correlation with lung function and negative correlation with airway inflammation and infection, correcting vitamin D deficiency may be an attractive therapeutic strategy in CF. The function of vitamin D is intricately tied to its metabolism, which may be impaired at multiple steps in patients with CF, with a potential to limit the efficacy of vitamin D supplementation. It is likely that the aforementioned beneficial properties of vitamin D require supplementation with doses of vitamin D markedly higher than those recommended to maintain proper bone function. This review will illustrate the potential for supplementation with vitamin D or its metabolites to modulate inflammation and improve defence against chronic infection in CF lung, as well as appropriate vitamin D supplementation strategies for improving lung function in CF.

Airway hyperreactivity is frequent in non‐asthmatic children with sickle cell disease

Asthma is associated with poorer outcomes in sickle cell disease (SCD). Whether AHR can exist in SCD as a distinct entity, separate and independent of asthma, is unknown.

Down-regulation of IL-8 by high-dose vitamin D is specific to hyperinflammatory macrophages and involves mechanisms beyond up-regulation of DUSP1

There is current interest in vitamin D as a potential anti‐inflammatory treatment for chronic inflammatory lung disease, including cystic fibrosis (CF). Vitamin D transcriptionally up‐regulates the anti‐inflammatory gene DUSP1, which partly controls production of the inflammatory chemokine IL‐8. IL‐8 is overabundant in CF airways, potentially due to hyperinflammatory responses of CF macrophages. We tested the ability of vitamin D metabolites to down‐regulate IL‐8 production in CF macrophages.

Stimulation of the RIG-I/MAVS Pathway by Polyinosinic:Polycytidylic Acid Upregulates IFN-β in Airway Epithelial Cells with Minimal Costimulation of IL-8

Pharmacological stimulation of the antiviral cytokine IFN-β in the airways may help to counter deleterious virus-induced exacerbations in chronic inflammatory lung diseases (asthma, chronic obstructive pulmonary disease, or cystic fibrosis). Polyinosinic-polycytidylic acid [poly(I:C)] is a known inducer of IFN-β but also costimulates an inflammatory response. The latter response is undesirable given the pre-existing airway inflammation in these diseases. The objective of our study was to identify conditions for poly(I:C) to selectively upregulate IFN-β in airway epithelial cells without a concomitant inflammatory response. The inflammatory response was gauged by production of the chemokine IL-8. Using cell lines and primary airway epithelial cells (both submerged and well-differentiated), we observed that pure poly(I:C) stimulated IFN-β mainly through the TLR3/TRIF pathway and IL-8 through an unidentified pathway. The magnitude of the IL-8 response stimulated by pure poly(I:C) matched or even exceeded that of IFN-β. Furthermore, this IL-8 response could not be pharmacologically downregulated without affecting IFN-β. In contrast, we show that stimulation of the RIG-I/MAVS pathway, such as when poly(I:C) is delivered intracellularly in a complex with liposomes or via nucleofection, selectively stimulates IFN-β with low IL-8 costimulation. The magnitude of IFN-β stimulation by liposome-encapsulated poly(I:C) is markedly diminished in well-differentiated cells. In conclusion, it is feasible to augment IFN-β production in airway epithelial cells without excessive costimulation of IL-8 if the RIG-I/MAVS pathway is stimulated, such as via liposomal delivery of poly(I:C). Better cytoplasmic delivery vehicles are needed to efficiently stimulate this pathway in well-differentiated cells.

Rhinovirus Load Is High despite Preserved Interferon-β Response in Cystic Fibrosis Bronchial Epithelial Cells.

Lung disease in cystic fibrosis (CF) is often exacerbated following acute upper respiratory tract infections caused by the human rhinovirus (HRV). Pathophysiology of these exacerbations is presently unclear and may involve deficient innate antiviral or exaggerated inflammatory responses in CF airway epithelial cells. Furthermore, responses of CF cells to HRV may be adversely affected by pre-exposure to virulence factors of Pseudomonas (P.) aeruginosa, the microorganism that frequently colonizes CF airways. Here we examined production of antiviral cytokine interferon-β and inflammatory chemokine interleukin-8, expression of the interferon-responsive antiviral gene 2’-5’-oligoadenylate synthetase 1 (OAS1), and intracellular virus RNA load in primary CF (delF508 CFTR) and healthy airway epithelial cells following inoculation with HRV16. Parallel cells were exposed to virulence factors of P. aeruginosa prior to and during HRV16 inoculation. CF cells exhibited production of interferon-β and interleukin-8, and expression of OAS1 at levels comparable to those in healthy cells, yet significantly higher HRV16 RNA load during early hours post-inoculation with HRV16. In line with this, HRV16 RNA load was higher in the CFBE41o- dF cell line overexpessing delF508 CFTR, compared with the isogenic control CFBE41o- WT (wild-type CFTR). Pre-exposure to virulence factors of P. aeruginosa did not affect OAS1 expression or HRV16 RNA load, but potentiated interleukin-8 production. In conclusion, CF cells demonstrate elevated HRV RNA load despite preserved interferon-β and OAS1 responses. High HRV load in CF airway epithelial cells appears to be due to deficiencies manifesting early during HRV infection, and may not be related to interferon-β.

125 Viral load is high despite preserved interferon-β response in rhinovirus-infected CF cells

Objectives Lung disease in cystic fibrosis (CF) is often exacerbated following acute upper respiratory tract infections. The majority of these exacerbations are associated with the human rhinovirus (HRV). Pathophysiology of these exacerbations is presently unclear. Potential mechanisms may involve impaired innate antiviral response in CF airway epithelial cells, the main replication site of HRV, or exaggerated inflammatory response by these cells. Furthermore, responses to HRV by CF cells may be adversely affected by chronic exposure to diffusible virulence factors of the opportunistic microorganism Pseudomonas aeruginosa , which frequently colonizes CF airways. Methods Here we examined HRV16 RNA load, production of the antiviral cytokine interferon-β and inflammatory chemokine interleukin-8, and expression of the interferon-responsive antiviral gene OAS1 in primary healthy and CF bronchial epithelial cells following infection with HRV16. Parallel cells were exposed to diffusible virulence factors of P. aeruginosa prior to infection with HRV16. Results We observed that CF cells exhibited high HRV16 RNA load, while production of interferon-β and interleukin-8, and expression of OAS1 were comparable to those in healthy cells. Pre-exposure to diffusible virulence factors of P. aeruginosa only mildly potentiated interleukin-8 response to HRV16, without affecting virus RNA load or interferon-b response. Conclusion CF cells demonstrate impaired HRV clearance with unaltered interferon-b or interleukin-8 responses. High HRV load in CF cells appear to be due to defective antiviral mechanisms unrelated to interferon-b.