370 research outputs found

    Immune response of healthy adults to the ingested probiotic 'Lactobacillus casei' Shirota

    Get PDF
    Daily ingestion of a probiotic drink containing Lactobacillus casei Shirota (LcS; 1.3 x 10(10) live cells) by healthy adults for (i) 4-weeks LcS, (ii) 6-weeks discontinuation of LcS, and (iii) a final 4-weeks of LcS, was investigated. There was a significant increase in expression of the T-cell activation marker CD3(+) CD69(+) in ex vivo unstimulated blood cells at weeks 10 and 14 and a significant increase in the NK cell marker CD3(+) CD16/56(+) in ex vivo unstimulated blood cells at weeks 4, 10 and 14. Expression of the NK cell activation marker CD16/56(+) CD69(+) in ex vivo unstimulated blood cells was 62% higher at week 10 and 74% higher at week 14. Intracellular staining of IL-4 in ex vivo unstimulated and PMA/ionomycin-stimulated CD3(+) β7(+) integrin blood cells was significantly lower at week 10 and 14. Intracellular staining of IL-12 in ex vivo unstimulated and LPS-stimulated CD14(+) blood cells was significantly lower at weeks 4, 10 and 14. Intracellular staining of TNF-α in LPS-stimulated CD14(+) blood cells was significantly lower at weeks 4, 10 and 14. Mucosal salivary IFN-γ, IgA1 and IgA2 concentrations were significantly higher at week 14 but LcS did not affect systemic circulating influenza A-specific IgA or IgG and tetanus specific IgG antibody levels. In addition to the decrease in CD3(+) β7(+) integrin cell IL-4 and a CD14(+) cell anti-inflammatory cytokine profile, at week 14 increased expression of activation markers on circulating T cells and NK cells and higher mucosal salivary IgA1 and IgA2 concentration indicated a secondary boosting effect of LcS. This article is protected by copyright. All rights reserved

    Factors influencing the mucosal immune response to exercise

    Get PDF
    Despite the abundance of research conducted into the effects of exercise on mucosal immunity the results remain controversial. Much of the inconsistencies arise from the exercise protocols, the participants studied and their nutritional status, as well as methodological and analytical differences. The purpose of this thesis was to examine the influence of some of these factors, and to investigate potential means of enhancing the mucosal immune response to exercise. In study 1 (Chapter 3) it was shown that a fed or fasted state 2 h prior to exercise had no effect on the s-IgA concentration or secretion rate during prolonged exercise. However, when participants were fed during exercise (Chapter 4), the secretion rate of salivary antimicrobial proteins lysozyme and a-amylase increased, but sIgA remained unchanged. These changes were likely due to the activation of mechanical and gustatory receptors leading to a reflex stimulation of protein secretion via the autonomic nerves, rather than changes in stress hOnliones, since cortisol did not change significantly during exercise. Study 3 (Chapter 5) extended these findings where it was demonstrated that chewing flavoured gum during exercise enhanced lysozyme and a-amylase secretion but resulted in a small reduction in s-IgA secretion rate. Salivary antimicrobial proteins are affected by the exercise intensity since both s-IgA and lysozyme secretion rate increased post -exercise following an incremental test to exhaustion, but not after exercise at 50% Y02max. Moreover, lysozyme secretion rate was also elevated following exercise at 75% Y02mru<, whereas s-IgA remained unchanged. These effects are thought to be mediated by increased sympathetic nervous system activity reflected by the concomitant increases in (lamylase and chromogranin A, rather than the hypothalamic-pituitary-adrenal axis. Resting mucosal immunity exhibits significant gender differences. In study 1 (Chapter 3) s-IgA concentration, secretion rate and osmolality were found to be lower in females than in males at rest. In addition, saliva flow rate was found to be lower in females compared with males in study 5 (Chapter 7). However, these differences did not appear to influence the salivary responses to acute exercise or exercise training. Chronic exercise training in elite male and female swimmers resulted in lower levels of s-IgA secretion rate following periods of intense training prior to competition compared with post-competition (Chapter 7), but these levels were not directly associated with reported episodes of respiratory illness.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Stimulating whole saliva affects the response of antimicrobial proteins to exercise

    Get PDF
    Stimulating whole saliva affects the response of antimicrobial proteins to exercis

    Effects of interrupting prolonged sitting with physical activity breaks on blood glucose, insulin and triacylglycerol measures : a systematic review and meta-analysis

    Get PDF
    Abstract: Background: Physical activity (PA) breaks in sitting time might attenuate metabolic markers relevant to the prevention of type 2 diabetes. Objectives: The primary aim of this paper was to systematically review and meta-analyse trials that compared the effects of breaking up prolonged sitting with bouts of PA throughout the day (INT) versus continuous sitting (SIT) on glucose, insulin and triacylglycerol (TAG) measures. A second aim was to compare the effects of INT versus continuous exercise (EX) on glucose, insulin and TAG measures. Methods: The review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) recommendations. Eligibility criteria consisted of trials comparing INT vs. SIT or INT vs. one bout of EX before or after sitting, in participants aged 18 or above, who were classified as either metabolically healthy or impaired, but not with other major health conditions such as chronic obstructive pulmonary disease or peripheral arterial disease. Results: A total of 42 studies were included in the overall review, whereas a total of 37 studies were included in the meta-analysis. There was a standardised mean difference (SMD) of − 0.54 (95% CI − 0.70, − 0.37, p = 0.00001) in favour of INT compared to SIT for glucose. With respect to insulin, there was an SMD of − 0.56 (95% CI − 0.74, − 0.38, p = 0.00001) in favour of INT. For TAG, there was an SMD of − 0.26 (95% CI − 0.44, − 0.09, p = 0.002) in favour of INT. Body mass index (BMI) was associated with glucose responses (β = − 0.05, 95% CI − 0.09, − 0.01, p = 0.01), and insulin (β = − 0.05, 95% CI − 0.10, − 0.006, p = 0.03), but not TAG (β = 0.02, 95% CI − 0.02, 0.06, p = 0.37). When energy expenditure was matched, there was an SMD of − 0.26 (95% CI − 0.50, − 0.02, p = 0.03) in favour of INT for glucose, but no statistically significant SMDs for insulin, i.e. 0.35 (95% CI − 0.37, 1.07, p = 0.35), or TAG i.e. 0.08 (95% CI − 0.22, 0.37, p = 0.62). It is worth noting that there was possible publication bias for TAG outcomes when PA breaks were compared with sitting. Conclusion: The use of PA breaks during sitting moderately attenuated post-prandial glucose, insulin, and TAG, with greater glycaemic attenuation in people with higher BMI. There was a statistically significant small advantage for PA breaks over continuous exercise for attenuating glucose measures when exercise protocols were energy matched, but no statistically significant differences for insulin and TAG

    Changes in insulin sensitivity in response to different modalities of exercise: a review of the evidence

    Get PDF
    Summary: Type 2 diabetes is an increasingly prevalent condition with complications including blindness and kidney failure. Evidence suggests that type 2 diabetes is associated with a sedentary lifestyle, with physical activity demonstrated to increase glucose uptake and improve glycaemic control. Proposed mechanisms for these effects include the maintenance and improvement of insulin sensitivity via increased glucose transporter type four production. The optimal mode, frequency, intensity and duration of exercise for the improvement of insulin sensitivity are however yet to be identified. We review the evidence from 34 published studies addressing the effects on glycaemic control and insulin sensitivity of aerobic exercise, resistance training and both combined. Effect sizes and confidence intervals are reported for each intervention and meta-analysis presented. The quality of the evidence is tentatively graded, and recommendations for best practice proposed

    A multi-ingredient containing carbohydrate, proteins L-glutamine and L-carnitine attenuates fatigue perception with no effect on performance, muscle damage or immunity in soccer players

    Get PDF
    We investigated the effects of ingesting a multi-ingredient (53g carbohydrate, 14.5g whey protein, 5g glutamine, 1.5g L-carnitine-L-tartrate) supplement, carbohydrate only, or placebo on intermittent performance, perception of fatigue, immunity, and functional and metabolic markers of recovery. Sixteen amateur soccer players ingested their respective treatments before, during and after performing a 90-min intermittent repeated sprint test. Primary outcomes included time for a 90-min intermittent repeated sprint test (IRS) followed by eleven 15 m sprints. Measurements included creatine kinase, myoglobin, interleukine-6, Neutrophil; Lymphocytes and Monocyte before (pre), immediately after (post), 1h and 24h after exercise testing period. Overall, time for the IRS and 15 m sprints was not different between treatments. However, the perception of fatigue was attenuated (P<0.001) for the multi-ingredient (15.9±1.4) vs. placebo (17.8±1.4) but not for the carbohydrate (17.0±1.9) condition. Several changes in immune/inflammatory indices were noted as creatine kinase peaked at 24h while Interleukin-6 and myoglobin increased both immediately after and at 1h compared with baseline (P<0.05) for all three conditions. However, Myoglobin (P<0.05) was lower 1h post-exercise for the multi-ingredient (241.8±142.6 ng·ml-1) and CHO (265.4±187.8 ng·ml-1) vs. placebo (518.6±255.2 ng·ml-1). Carbohydrate also elicited lower neutrophil concentrations vs. multi-ingredient (3.9±1.5 109/L vs. 4.9±1.8 109/L, P = 0.016) and a reduced (P<0.05) monocytes count (0.36±0.09 109/L) compared to both multi-ingredient (0.42±0.09 109/L) and placebo (0.42±0.12 109/L). In conclusion, multi-ingredient and carbohydrate supplements did not improve intermittent performance, inflammatory or immune function. However, both treatments did attenuate serum myoglobin, while only carbohydrate blunted post-exercise leukocytosis

    Islet autoantibody status in a multi-ethnic UK clinic cohort of children presenting with diabetes.

    Get PDF
    OBJECTIVE: We prospectively determined islet autoantibody status in children presenting with diabetes to a single UK region in relation to ethnicity. DESIGN: 316 (68.0% non-white) children presenting with diabetes between 2006 and 2013 were tested centrally for islet cell autoantibodies (ICA) and glutamic acid decarboxylase autoantibodies (GAD-65) at diagnosis, and if negative for both, tested for insulin autoantibodies (IAA). The assay used to measure GAD-65 autoantibodies changed from an in-house to a standardised ELISA method during the study. RESULTS: Even with use of the standardised ELISA method, 25.8% of children assigned a diagnosis of type 1 diabetes still tested negative for all three autoantibodies. 30% of children assigned a diagnosis of type 2 diabetes were autoantibody positive, and these had the highest glycated haemoglobin (HbA1c) levels at 12 months follow-up compared with other groups (p value for analysis of variance <0.001), although the sample size was small. Autoantibody positivity was similar between non-white and white children regardless of assay used (60.0% (n=129) vs 56.4% (n=57), χ2=0.9, p=0.35), as was mean GAD-65 autoantibody levels, but fewer non-white children had two or more autoantibodies detectable (13% (n=28) vs 27.7% (n=28), χ2=12.1, p=0.001). CONCLUSION: Islet autoantibody positivity was associated with a more severe phenotype, as demonstrated by poorer glycaemic control, regardless of assigned diabetes subtype. Positivity did not differ by ethnic group
    • …
    corecore