Oxidative Burst Activity Research Articles

Effects of a freeze-dried juice blend powder on exercise-induced inflammation, oxidative stress, and immune function in cyclists

A freeze-dried fruit and vegetable juice powder (JUICE) was investigated as a countermeasure nutritional strategy to exercise-induced inflammation, oxidative stress, and immune perturbations in trained cyclists. Thirty-four cyclists (25 male, 9 female) were randomized to control (nonJUICE) or JUICE for 17 days. JUICE provided 230 mg·day(-1) of flavonoids, doubling the typical adult daily intake. During a 3-d period of intensified exercise (days 15-17), subjects cycled at 70%-75% V̇O2max for 2.25 h per day, followed by a 15-min time trial. Blood samples were collected presupplementation, post supplementation (pre-exercise), and immediately and 14-h post exercise on the third day of exercise. Samples were analyzed for inflammation (interleukin (IL)-6, IL-8; tumor necrosis factor alpha (TNFα); monocyte chemoattractant protein-1 (MCP-1)), oxidative stress (oxygen radical absorbance capacity (ORAC), ferric reducing ability of plasma (FRAP), reduced and oxidized glutathione, protein carbonyls), and innate immune function (granulocyte (G-PHAG) and monocyte (M-PHAG) phagocytosis and oxidative burst activity). A 2 (group) × 4 (time points) repeated measures ANOVA revealed significant time effects due to 3 days of exercise for IL-6 (396% increase), IL-8 (78% increase), TNFα (12% increase), MCP-1 (30% increase), G-PHAG (38% increase), M-PHAG (36% increase), FRAP (12.6% increase), ORAC (11% decrease at 14 h post exercise), and protein carbonyls (82% increase at 14 h post exercise) (p < 0.01). No significant interaction effects were found for any of the physiological measures. Although providing 695 gallic acid equivalents of polyphenols per day, JUICE treatment for 17 days did not change exercise-induced alterations in inflammation and oxidative stress or immune function in trained cyclists after a 3-day period of overreaching.

Deficient cytokine expression and neutrophil oxidative burst contribute to impaired cutaneous wound healing in diabetic, biofilm‐containing chronic wounds

Diabetic patients exhibit dysregulated inflammatory and immune responses that predispose them to chronic wound infections and the threat of limb loss. The molecular underpinnings responsible for this have not been well elucidated, particularly in the setting of wound biofilms. This study evaluates host responses in biofilm-impaired wounds using the TallyHo mouse, a clinically relevant polygenic model of type 2 diabetes. No differences in cytokine or Toll-like receptor (TLR) expression were noted in unwounded skin or noninoculated wounds of diabetic and wild-type mice. However, diabetic biofilm-containing wounds had significantly less TLR 2, TLR 4, interleukin-1β, and tumor necrosis factor-α expression than wild-type wounds with biofilm (all p < 0.001). Both groups had similar bacterial burden and neutrophil infiltration after development of biofilms at 3 days postwounding, but diabetic wounds had significantly less neutrophil oxidative burst activity. This translated into a log-fold greater bacterial burden and significant delay of wound epithelization for biofilm-impaired diabetic wounds at 10 days postwounding. These results suggest that impaired recognition of bacterial infection via the TLR pathway leading to inadequate cytokine stimulation of antimicrobial host responses may represent a potential mechanism underlying diabetic susceptibility to wound infection and ulceration.

Pathogenesis of Chagas Cardiomyopathy: Role of Inflammation and Oxidative Stress

Described by the Brazilian scientist Carlos Chagas more than a century ago, Chagas disease (ChD) currently affects 8 to 10 million persons and causes more than 10 000 deaths each year.[1][1] Originally confined to Latin American countries, ChD had been considered an exotic disease and received less

Immune and inflammation responses to a 3-day period of intensified running versus cycling

Functional overreaching has been linked to alterations in immunity and host pathogen defense, but little is known as to whether or not running and cycling evoke different responses. This study compared inflammation, muscle damage and soreness, and innate immune function responses to a 3-day period of intensified exercise in trained long distance runners (N=13, age 34.4±2.4year) and cyclists (N=22, age 36.6±1.7year, P=0.452). Upper respiratory tract infection (URTI) symptomatology was monitored for 12weeks using the Wisconsin Upper Respiratory Symptom Survey (WURSS), and subjects from both athletic groups came to the lab during week five and exercised 2.5h/day for 3days in a row at 70% VO2max. Blood samples were collected before and after the 3-day period of exercise, with recovery samples collected 1-, 14-, and 38h-post-exercise. Samples were analyzed for muscle damage [creatine kinase (CK), myoglobin (MYO)], inflammation (CRP, IL-6, IL-8, IL-10, MCP), and innate immunity [granulocyte and monocyte phagocytosis (GR-PHAG and MO-PHAG) and oxidative burst activity (GR-OBA and MO-OBA)]. Runners compared to cyclists experienced significantly more muscle damage (CK 133% and MYO 404% higher post-3days exercise), inflammation (CRP 87%, IL-6 256%, IL 8 61%, IL-10 32%, MCP 29%), and delayed onset of muscle soreness (DOMS, 87%). The 3-day period of exercise caused significant downturns in GR-PHAG, MO-PHAG, GR-OBA, MO-OBA by 14- and 38h-recovery, but the pattern of change did not differ between groups. No group differences were measured for 12-week URTI severity (18.3±5.6 and 16.6±4.0, P=0.803) and symptom scores (33.4±12.6 and 24.7±5.8, P=0.477). These data indicate that a 3-day period of functional overreaching results in substantially more muscle damage and soreness, and systemic inflammation in runners compared to cyclists, but without group differences for 12-week URTI symptomatology and post-exercise decrements in innate immune function.

Latent cytomegalovirus infection and innate immune function following a 75 km cycling time trial

This study compared the acute immune response, inflammation, and lipid peroxidation to a 75km cycling time trial in male athletes testing positive or negative for latent cytomegalovirus (CMV) infection. Trained cyclists (N=20) were tested for CMV serostatus, and cycled 75km on a mountainous course using indoor trainers with continuous workload monitoring. Pre-, post-, and 1h post-exercise blood samples were analyzed for total blood leukocyte counts, blood granulocyte (GR) and monocyte (MO) phagocytosis (PHAG) and oxidative burst activity (OBA), four plasma cytokines, and plasma F2-isoprostanes. Forty percent of the subjects tested positive for CMV. No differences in subject characteristics were found between CMVpos and CMVneg groups. Mean power (57.3±1.6, 59.4±1.8% maximal Watts, p=0.803), heart rate (87.0±1.0, 86.5±1.3% maximal heart rate, p=0.376), and total time (2.56±0.08, 2.60±0.08h, p=0.744) to complete the 75km cycling time trial did not differ between CMVpos and CMVneg groups. Whereas exercise induced significant changes in total blood leukocyte counts, GR and MO-PHAG, four plasma cytokines, and plasma F2-isoprostanes (p<0.05, ω(2)>0.03), these exercise-induced changes did not differ between CMVpos and CMVneg groups (p>0.05, ω(2)<0.01). CMV serostatus does not appear to influence these innate immune responses or markers of inflammation and lipid peroxidation in response to a single bout of heavy exertion.

Prior reproductive experience alters prolactin-induced macrophage responses in pregnant rats

Reproductive experience (i.e., pregnancy and lactation) induces physiological changes in mammals. A previous reproductive experience was recently shown to modulate the activity of dopaminergic hypothalamic systems while decreasing serum prolactin levels and oxidative burst activity in peritoneal macrophages. Dopamine receptor antagonists increase serum prolactin levels, and both prolactin and dopamine receptors may be involved in the modulation of macrophage activity, providing a means of communication between the nervous and immune systems. The present study evaluated the in vitro effects of prolactin and a dopamine D2 receptor antagonist on the peritoneal activity of macrophages from primigravid and multigravid female rats during the third trimester of pregnancy. Oxidative bursts and phagocytosis in peritoneal macrophages were evaluated by flow cytometry. Primigravid and multigravid Wistar rats, during the third trimester of pregnancy (i.e., days 17–21), were used. Peritoneal fluid samples from these rats were first incubated with prolactin (10 and 100nM) for different periods of time. The same procedure was repeated to evaluate the effects of domperidone (10 and 100nM) on macrophage activity. Our results showed that macrophages from multigravid rats responded more effectively to in vitro incubation with prolactin, especially with regard to the intensity and percentage of phagocytosis. Additionally, these effects were more pronounced after incubation periods of 30min or 4h. These data suggest that macrophages during a second pregnancy become more sensitive to the phagocytotic effects of prolactin.

The SOD mimic MnTM-2-PyP(5+) reduces hyaluronan degradation-induced inflammation in mouse articular chondrocytes stimulated with Fe (II) plus ascorbate

In pathological conditions, oxidative burst generates hyaluronan (HA) fragmentation with a consequent increase in the number of small HA oligosaccharides. These fragments are able to stimulate an inflammatory response in different cell types by activating the CD44 and the toll-like receptors 4 (TLR-4) and 2 (TLR-2). The stimulation of CD44 and TLRs in turn activates the NF-kB which induces the production of several pro-inflammatory mediators that amplify and perpetuate inflammation. We aimed to study the antioxidant effect of the SOD mimic, synthetic manganese porphyrin, Mn(III) 5,10,15,20-tetrakis(N-methylpyridinium-2-yl)porphyrin (MnTM-2-PyP5+) on preventing HA degradation in mouse articular chondrocytes stimulated with Fe (II) plus ascorbate. Fe (II) plus ascorbate stimulation induced oxidative burst confirmed by high levels of hydroxyl radical/peroxynitrite production, increased lipid peroxidation and HA degradation. HA fragments highly induced mRNA expression and the related protein production of CD44, TLR-4 and TLR-2, NF-kB activation and significantly up-regulated the inflammatory cytokines, tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), and other pro-inflammatory mediators, i.e. matrix metalloprotease 13 (MMP-13) and inducible nitric oxide synthase (iNOS). Treatment of cells with MnTM-2-PyP5+was able to attenuate oxidative burst, HA degradation and NF-kB activation, and markedly decreased mRNA expression of CD44, and TLRs and the related protein synthesis, as well as the levels of up-regulated inflammatory mediators. Adding a specific HA-blocking peptide (PEP-1) to cells significantly reduced all the inflammatory parameters up-regulated by Fe (II) plus ascorbate, and increased MnTM-2-PyP(5+) activity. These findings suggest that HA degradation plays a key role in the initial inflammatory response of cartilage and antioxidants and could be a useful tool to prevent the propagation of this mechanism.

Successful Unrelated Cord Blood Stem Cell Transplantation in an X-linked Chronic Granulomatous Disease Patient with Disseminated BCG-induced Infection

A 19-month-old boy with chronic granulomatous disease (CGD) received umbilical cord blood transplantation (UCBT) from an unrelated donor after experiencing a life-threatening disseminated Bacillus Calmette-Guérin infection. After busulfan and cyclophosphamide conditioning, we performed a 5/6-matched UCBT. Engraftment and mixed chimerism was 100% in peripheral blood, and 100% of his neutrophils had normal oxidative burst activity on day 17. The patient is now 3 years old, free from infection, and growing well. To our knowledge, this is the second case of CGD treated with UCBT in Taiwan. His successful outcome illustrates that UCBT in a patient with CGD should be considered early if a human leukocyte antigen-matched donor is not available or the patient has just recovered from a severe infection.

Blood phagocyte activity after race training sessions in Thoroughbred and Arabian horses

Intensive exercise and exertion during competition promote many changes that may result in the impairment of immunity and increased susceptibility to infections. The aim of this study was to evaluate the activity of “the first line of defense”: neutrophils and monocytes in racing Thoroughbred and Arabian horses after routine training sessions. Twenty-three (12 Thoroughbred and 11 Arabian) horses were examined. Routine haematological (number of red blood cells – RBC, haemoglobin concentration – HGB, haematocrit – HCT, total number of white blood cells – WBC), biochemical (creatine phosphokinase activity – CPK and total protein concentration – TP) parameters, cortisol concentration as well as phagocytic and oxidative burst activity of neutrophils and monocytes were determined. The values of basic parameters and the activity of phagocytes differed between breeds and distinct patterns of exercise-induced changes were observed. The training sessions did not produce the decrease in phagocyte activity that might lead to the suppression of immunity.

Functional analyses of lymphocytes and granulocytes isolated from the thymus, spiral valve intestine, spleen, and kidney of juvenile Australian lungfish, Neoceratodus forsteri

Our current understanding of the lungfish immune system is limited. This study is characterizing the immune cells separated from primary and secondary immune organs of the Australian lungfish, Neoceratodus forsteri. Our functional studies utilized flow cytometry to study the immune cells extracted from the thymus, spiral valve intestine, spleen, and kidney. The different characteristics of lymphocytes and granulocytes were analyzed by utilization of viability, phagocytosis, oxidative burst, and apoptosis assays. Most of the nonviable intestinal cells were lymphocytes. Depending on the organ, 6–25% of the total population, predominantly granulocytes, underwent phagocytosis where the splenic cells were the most and intestinal cells the least phagocytic cells. Cells responded positively but differently to stimulation with phorbol myristate acetate (PMA) to produce radical oxygen species, an indication of their oxidative burst activity, which was mainly associated with granulocytes. Although cells were induced by dexamethasone to undergo apoptosis, such an induction did not follow a consistent pattern of dose of dexamethasone or incubation time between the different organs. In the absence of monoclonal antibodies against lungfish immune cells, these functional flow cytometric analyses aid our understanding on the functionality of immune cells.

Antioxidative burst and hepatoprotective effects of ethanol root extract of Hippocratea africana against paracetamol-induced liver injury

Context: Hippocratea africana (Willd.) Loes. ex Engl. (Celastraceae) root is used traditionally as an antipoison or antidote to treat liver diseases.Objective: To evaluate antioxidative burst and hepatoprotective potentials of H. africana against paracetamol-induced liver injury in rats.Materials and method: Antioxidative burst activity of the extract (1–100 µg/ml) in whole blood, neutrophils and macrophages was investigated using a luminol/lucigenin-based chemiluminescence assay. The hepatoprotective effect of the extract (200–600 mg/kg) was evaluated by the assay of liver function parameters, antioxidant enzymes and histopathological studies of the liver. GC-MS analyses of hexane and dichloromethane fractions were also carried out.Results and discussion: The root extract/fractions exerted pronounced inhibition of oxidative burst activity in whole blood, neutrophils (intracellular and extracellular) and macrophages (3.04–99.70%). The administration of the root extract caused significant (p < 0.05–0.001) reduction of high levels of liver enzymes (AST, ALT and ALP), total cholesterol, direct and total bilirubin as well as elevation of serum levels of total protein, albumin and antioxidant enzymes (SOD, CAT, GPx and GSH). Histology of the liver sections of extract and silymarin-treated animals showed reductions in the pathological features compared to the paracetamol-treated animals. The chemical pathological changes were consistent with histopathological observations suggesting a marked hepatoprotective effect of the root extract of H. africana. The GC-MS analysis revealed some pharmacologically active compounds.Conclusion: The results show that the root extract of H. africana has hepatoprotective potential probably due to its antioxidative burst activity.

Oxidative burst intensity of peripheral phagocytic cells and periodontitis in Down syndrome

This study investigated the oxidative burst function of peripheral phagocytic cells (granulocytes and monocytes) and assessed the relation between oxidative burst and periodontal status in adult individuals with Down syndrome (DS) vs. other groups. Of 55 DS individuals (18-56years old), 74 individuals with mental retardation (MR) and 88 medically healthy controls (HC) participated in the study. The MR and HC groups were age, race and gender matched with the DS group. Gingival index, plaque index, probing depth, attachment level and bleeding on probing were recorded for each subject. Whole blood was collected for granulocyte/monocyte oxidative burst tests. Oxidative burst was determined by flow cytometry in terms of percentage of cells actively involved in oxidative burst, and oxidative intensity (magnitude of ROIs per cell). The basal oxidative burst intensity of DS granulocytes was higher than that of HC and MR granulocytes (p=0.05). The Escherichia coli stimulated oxidative burst intensity of DS monocytes was higher than that of HC and MR monocytes (p=0.05). Regression analysis controlling for age, sex, race and plaque levels showed a significant association between monocyte oxidative burst intensity and loss of periodontal attachment in DS subjects (p<0.01). Regression analysis also showed a significant association between granulocyte oxidative burst intensity and bleeding on probing in all subjects (p<0.05). Oxidative burst activity of peripheral monocytes and granulocytes is elevated in DS affected individuals and may contribute to periodontal tissue inflammation and loss of periodontal attachment in this susceptible group.

Association of monocyte CCR2 expression with obesity and insulin resistance in postmenopausal women

Monocytes actively participate in inflammatory mechanisms that contribute to the development of adipose tissue dysfunction and atherogenesis. The aim of this study was to evaluate the association of monocyte CCR2 chemokine receptor expression and intracellular oxidative burst with the metabolic and inflammatory factors related to body weight. The study was performed in 67 postmenopausal women with normal, overweight and obese body mass index. Monocyte CCR2 surface expression and intracellular oxidative burst activity (determined using 2', 7'-dichlorofluorescin diacetate) were analyzed by flow cytometry. Serum levels of HMW adoponectin, monocyte chemoattractant protein-1 (MCP-1), insulin, glucose, lipids and C-reactive protein were determined. Subjects with homeostasis model assessment-estimated insulin resistance (HOMA-IR) above the median had significantly higher proportion of CCR2+ monocytes and higher mean fluorescence intensity (MFI) of CCR2 and oxidative burst. The proportion of CCR2+ monocytes and CCR2 MFI were correlated with body weight, body mass index, fat mass, insulin and HOMA-IR. Oxidative burst also correlated with anthropometric measures, fat mass and expression of CCR2. No correlations were found between these markers of monocyte activation and HMW adiponectin or monocyte chemoattractant protein-1. The absolute number of monocytes was associated with insulin and this association remained significant after adjusting for C-reactive protein. In the multiple regression model the monocyte number was determined to be an independent predictor of insulin level. These results provide support for significant associations of monocyte number and markers involved in monocyte activation with obesity and insulin resistance.

Modulation of immune functions in polymorphonuclear neutrophils induced by physostigmine, but not neostigmine, independent of cholinergic neurons

BackgroundCholinesterase inhibitors (Ch-I) improve survival in experimental sepsis consistent with activation of the cholinergic-anti-inflammatory-pathway. So far, less is known about whether Ch-I have a direct immunomodulatory effect on immune cells (polymorphonuclear neutrophils, PMN) in the absence of cholinergic neurons. We investigated the concentration–response-effects of physostigmine and neostigmine on the oxidative burst activity (human and rat PMN) and the expression of adhesion molecules on the surface of human PMN under in vitro conditions. MethodsPMN from 10 healthy humans or 10 rats were pretreated with 2, 10, 24, 97μM physostigmine or 3, 15, 30, 150μM neostigmine, primed with tumor-necrosis-factor-alpha (TNF-alpha) followed by stimulation with n-formyl-methionyl-leucylphenylalanine (fMLP) or stimulated with phorbol-12-myristate-13-acetate (PMA). Human and rat samples were assessed by flow cytometry for the generation of oxidative free radicals. Stimulated human PMN were additionally incubated with antibodies against Mac-1 (CD11b) or L-selectin (CD62l). ResultsPhysostigmine and neostigmine did not alter oxidative burst activity or the expression of adhesion molecules of PMN induced by receptor-dependent activators like fMLP or TNF-alpha/fMLP (rat and human PMN, p=n.s.). Physostigmine, but not neostigmine, inhibited the protein-kinase-C-mediated oxidative burst activity by PMA in a dose-dependent manner (rat and human PMN, p<0.05). Physostigmine, in the concentration range tested, suppressed the expression of CD11b following stimulation with PMA not significantly (human PMN: control: 63.1±10.7 vs. 97μM physostigmine: 49.9±12.8 MESF, p=n.s.). ConclusionWhile neostigmine has no effect on functional and phenotypic changes of PMN, the lipid soluble Ch-I physostigmine causes a dose dependent reduction in PMA-induced oxidative burst, independent of neuronal released acetylcholine.

Serial evaluation of neutrophil function in tumour‐bearing dogs undergoing chemotherapy

We hypothesized that neutrophil function in tumour-bearing dogs is negatively impacted by chemotherapy. Flow cytometric techniques were used to assess neutrophil oxidative burst and phagocytic activities at baseline, 7 and 21 days after induction chemotherapy in 20 dogs with lymphoma. Dogs had a lower percentage of neutrophils exhibiting oxidative burst activity after stimulation with Escherichia coli (day 7; P = 0.009) and phorbol 12-myristate 13-acetate (PMA) (days 7 and 21; P = 0.0003 and P = 0.01, respectively), compared with healthy controls. From day 0 to 7, the percentage of neutrophils exhibiting oxidative burst activity decreased after stimulation with E. coli (P = 0.016) and PMA (P = 0.0006). Induction chemotherapy suppresses the percentage of neutrophils capable of oxidative burst in dogs with lymphoma, with improvement in phagocytic activity over time (P = 0.03). The impact of neutrophil dysfunction on incidence and severity of sepsis in dogs receiving chemotherapy should be investigated.

Identification of anti-inflammatory and other biological activities of 3-carboxamide, 3-carbohydrazide and ester derivatives of gatifloxacin.

BackgroundSeventeen 1,4-dihydroquinoline-3-carboxamide and 1,4-dihydroquinoline-3-carbohydrazide derivatives of gatifloxacin have been prepared with a facile one step synthesis aiming to improve antibacterial, antifungal and immunological activities. The methodology allows the introduction of a variety of substituents such as amines, alcohol, phenol, amides and alkyl halides into the core structure of gatifloxacin.ResultsThe analog N-(3-aminophenyl)-1-cyclopropyl-6-fluoro-8-methoxy-7-(3-methylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxamide has been identified as a potentially excellent anti-inflammatory agent, which exhibited highly potent effects on the oxidative burst activity of whole blood phagocytes (IC50 <12.5 μg mL-1), neutrophils (IC50 <0.1 μg mL-1) and macrophages phagocytes (IC50 <3.1 μg mL-1) as well as potent T-cell proliferation inhibitory effect (IC50 3.7 μg mL-1) while having comparable antibacterial activity to gatifloxacin. Another analog, 1-cyclopropyl-6-fluoro-8-methoxy-7-(3-methylpiperazin-1-yl)-4-oxo-N-phenyl-1,4-dihydroquinoline-3-carbohydrazide has tremendous T-cell proliferation inhibitory effect IC50 <3.1 μg mL-1 as compared to prednisolone, whereas, 3,5-dihydroxyphenyl1-cyclopropyl-6-fluoro-8-methoxy-7-(3-methylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylate and 2-hydroxyphenyl-1-cyclopropyl-6-fluoro-8-methoxy-7-(3-methylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylate envision good inhibitory activity on T-cells proliferation (IC50 6.8 & 8.8 μg mL-1 respectively).ConclusionsThe structural modification at carboxylic group has resulted in improved anti-inflammatory activities with comparable antibacterial activity to gatifloxacin. We believe that C3 structural modifications of gatifloxacin are definitely important in bringing major immunomodulatory changes in these compounds.

Immunomodulatory properties of surfactant preparations

Surfactant replacement significantly decreased acute pulmonary morbidity and mortality among preterm neonates with respiratory distress syndrome. Besides improving lung function and oxygenation, surfactant is also a key modulator of pulmonary innate and acquired immunity regulating lung inflammatory processes. In this review, we describe the immunomodulatory features of surfactant preparations. Various surfactant preparations decrease the proinflammatory cytokine and chemokine release, the oxidative burst activity, and the nitric oxide production in lung inflammatory cells such as alveolar neutrophils, monocytes and macrophages; they also affect lymphocyte proliferative response and immunoglobulin production, as well as natural killer and lymphokine-activated killer cell activity. In addition, surfactant preparations are involved in airway remodeling, as they decrease lung fibroblast proliferation capacity and the release of mediators involved in remodeling. Moreover, they increase cell transepithelial resistance and VEGF synthesis in lung epithelial cells. A number of different signaling pathways and molecules are involved in these processes.Because the inhibition of local immune response may decrease lung injury, surfactant therapeutic efficacy may be related not only to its biophysical characteristics but, at least in part, to its anti-inflammatory features and its effects on remodeling processes. However, further studies are required to identify which surfactant preparation ensures the highest anti-inflammatory activity, thereby potentially decreasing the inflammatory process underlying respiratory distress syndrome. In perspective, detailed characterization of these anti-inflammatory effects could help to improve the next generation of surfactant preparations.

Consumption of Bifidobacterium lactis Bi-07 by healthy elderly adults enhances phagocytic activity of monocytes and granulocytes.

Elderly adults have alterations in their gut microbiota and immune functions that are associated with higher susceptibility to infections and metabolic disorders. Probiotics and prebiotics, and their synbiotic combinations are food supplements that have been shown to improve both gut and immune function. The objective of this randomised, double-blind, placebo-controlled, cross-over human clinical trial was to study immune function and the gut microbiota in healthy elderly adults. Volunteers (n 37) consumed prebiotic galacto-oligosaccharides (GOS; 8g/d), probiotic Bifidobacterium lactis Bi-07 (Bi-07; 10(9) colony-forming units/d), their combination (Bi-07+GOS) and maltodextrin control (8g/d) in four 3-week periods separated by 4-week wash-out periods. Immune function was analysed by determining the phagocytic and oxidative burst activity of monocytes and granulocytes, whole-blood response to lipopolysaccharide, plasma chemokine concentrations and salivary IgA levels. Gut microbiota composition and faecal SCFA content were determined using 16S ribosomal RNA fluorescence in situ hybridisation and HPLC, respectively. Primary statistical analyses indicated the presence of carry-over effects and thus measurements from only the first supplementation period were considered valid. Subsequent statistical analysis showed that consumption of Bi-07 improved the phagocytic activity of monocytes (P<0·001) and granulocytes (P=0·02). Other parameters were unchanged. We have for the first time shown that the probiotic Bi-07 may provide health benefits to elderly individuals by improving the phagocytic activity of monocytes and granulocytes. The present results also suggest that in the elderly, the effects of some probiotics and prebiotics may last longer than in adults.

Cellular antioxidative, cytotoxic, and antileishmanial activities of Homalium letestui.

Homalium letestui Pellegr (Flacourtiaceae) is used in traditional medicine in parts of Nigeria for the treatment of malaria, ulcer, and inflammatory diseases and as an aphrodisiac. This investigation was aimed to evaluate the cytotoxic, immunomodulatory, and antileishmanial properties of stem extract and fractions of Homalium letestui (H. letestui). Cytotoxic activity against HeLa cells was done using sulphorhodamine (SRB) method and DNA interaction activity using gel electrophoresis. Immunomodulatory activity of the extract in whole blood, neutrophils, and macrophages was also investigated using luminol/lucigenin-based chemiluminescence assay. The extract and fractions were similarly screened for antileishmanial activity against promastigotes of Leishmania major in vitro. The GCMS analysis of the most active fraction against HeLa cells was carried out. The stem extract exerted prominent cytotoxic activity with the dichloromethane fraction exhibiting the most pronounced effect (GI50 -5.12±1.45 µg/ml, LC50- 57.3±2.33 µg/ml, TGI -12.6±0.87 µg/ml). The crude extract and the fractions did not interact with DNA when investigated using electrophoresis. The extract significantly ((p<0.05 - 0.001) inhibited oxidative burst activity in whole blood (-27.90-66.90%), isolated polymorphonuclear cells (PMNs) (16.50-67.0%), and mononuclear cells (MNCs) (4.31-98.50%) when two different phagocytosis activators (serum opsonizing zymosan-A and PMA) were used. The extract also exhibited moderate antileishmanial activity against promastigotes of Leishmania major in vitro. GCMS analysis of active fraction revealed pharmacologically active compounds. These results suggest that the stem extract/fractions of H. letestui possess cytotoxic, immunomodulatory, and antileishmanial activities.

Effect of transgastric peritoneal access on peritoneal innate cellular immunity: experimental study in swine

One of the main concerns of natural orifice surgery is the local and systemic impact on physiology. Few studies have compared natural orifice transluminal endoscopic surgery (NOTES) with other surgical modalities. Most studies are based on systemic variables such as postoperative serum cytokines, with conflicting results. Surgical trauma induces an early inflammatory response, release of cytokines, and local leukocyte activation and oxidative burst. Major surgical trauma is related to impairment of phagocytic function and an increase in production of active oxygen species by phagocytes. The aim of this study was to evaluate the impact of transgastric peritoneoscopy on peritoneal innate immune response compared with laparoscopy and laparotomy in swine. Thirty-four male Sus scrofa domesticus swine were assigned to four groups: transgastric peritoneoscopy (13), laparoscopy (7), laparotomy (7), and sham procedure (7). Twenty-four hours after the procedure, peritoneal fluid cells were harvested by peritoneal washing after necropsy. Flow cytometry analysis of labeled S. aureus and E. coli phagocytosis by peritoneal neutrophils and macrophages was blindly performed. Oxidative burst activity measured by H(2)O(2) production under different challenges was also evaluated. Total operative time varied between all groups. The transgastric, laparoscopy, and laparotomy groups required 56, 17.2, and 40.3 min of mean operative time, respectively (p < 0.05). Even though the mean percentage and intensity of phagocytosis by peritoneal phagocytes were higher in the sham, transgastric, and laparoscopy groups, there was no significant difference between these groups and laparotomy. Macrophage production of H(2)O(2) has been shown to be similar among the transgastric, laparoscopy, and sham groups, and smaller than that in laparotomy (p < 0.05), either under basal conditions, while performing E. coli phagocytosis, or challenged by the presence of E. coli membrane lipopolysaccharide. Under the conditions of this study, transgastric peritoneoscopy has been shown to have minimal impact on peritoneal innate immune response.