Examination of Bovine Red Blood Cell Death in Vitro in Response to Pathophysiologic Proapoptotic Stimuli.

BACKGROUND: Interspecies variations in mammalian red blood cells (RBCs) are observed in circulating RBC lifespan, cell size, fluidity, aggregation, water permeability, metabolism, lipid composition, and the overall proteome. Bovine RBC cell membrane is deficient in phosphatidylcholine and exhibits anomalies in the arrangement of phosphatidylethanolamine within the lipid bilayer. However, like human RBCs, virtually all the aminophospholipid phosphatidylserine (PS) is found within the cytoplasmic side of the cell membrane of intact circulating bovine RBCs. During apoptotic cell death of human and murine RBCs, PS translocates to the outer leaflet of the cell membrane via Ca2+-dependent and -independent signaling mechanisms. However, little is known about this process in bovine RBCs. METHODS: Using cytofluorometry analyses, we characterized and compared the cell death responses in bovine and human RBCs in vitro exposed to various pathophysiologic cell stressors. RESULTS: Ionic stress, by ionophore treatment, and oxidative stress enhanced cytoplasmic Ca2+ levels and cell membrane PS expression in both bovine and human RBCs. Fever-grade hyperthermia and energy starvation promoted Ca2+ influx and elevated reactive oxygen species levels in both human and bovine RBCs. However, bovine RBCs displayed minimal increases in PS expression elicited by hyperthermia, energy starvation, and extracellular hypertonicity as compared to human RBCs. In response to decreased extracellular osmolality, bovine RBCs exhibited significantly enhanced fragility as compared to human RBCs. CONCLUSIONS: Bovine RBCs display differential cell death patterns as compared to human RBCs, only partly explained by increased Ca2+ influx and oxidative stress. Premature removal of circulating RBCs could potentially contribute to the pathogenesis of anemia in cattle caused by a wide range of factors such as systemic diseases, parasitic infections, and nutritional deficiencies.

Effects of high intensity interval training on cardiorespiratory fitness and salivary levels of IL-8, IL-1ra, and IP-10 in adults with asthma and non-asthma controls.

OBJECTIVE: The purpose of this study was to determine whether high intensity interval training (HIIT) would lead to improvements in 1) maximal VO2, VE, VE/VCO2, and VE/MVV, and/or 2) resting salivary concentrations of pro-inflammatory markers Interleukin (IL-8), interferon-gamma-inducible-protein (CXCL10/IP-10)) and anti-inflammatory marker IL-1 receptor antagonist (IL-1ra) in adults with well-controlled asthma compared to non-asthma controls. METHODS: Participants completed a maximal exercise test at the beginning (T1) and end (T2) of a 6-week HIIT intervention; saliva samples were obtained at the beginning and 30 min following the first (T1) and last (T2) exercise session. RESULTS: Adults with asthma (n = 20; age: 21.4 ± 2.4 years) and non-asthma controls (n = 12; age: 22.5 ± 3.4 years) completed the intervention. VO2max increased from T1 to T2 in both groups (asthma T1 32.9 ± 8, T2 38.6 ± 8.2 ml/kg/min; controls T1 34.5 ± 11.8, T2 38.9 ± 12.3 ml/kg/min). VEmax also increased in both groups (asthma T1 97.7, T2 110.8 units, p < 0.001, hp2 = <0.04; control T1 106.3, T2 118.1, p < 0.001, hp2 0.02). An increase in VE/VCO2 (F(1, 10)=22.11, p = 0.001) and VE/MVV (F(1, 10) = 111.30, p < 0.001) was observed in the control group; no differences were observed in the asthma group. No differences in IL-8 or IL-1ra were observed between groups. In the asthma group, resting salivary IP-10 concentrations significantly decreased from T1 (0.025 pg/ug protein) to T2 (0.015 pg/ug protein, p = 0.039, hp2 = 0.3 (moderate effect)). CONCLUSION: A 6-week HIIT intervention led to a similar increase in VO2max and VEmax in those with and without asthma, and a decrease in resting salivary IP-10 levels among adults with asthma.

Effects of design, porosity and biodegradation on mechanical and morphological properties of additive-manufactured triply periodic minimal surface scaffolds.

The main aim of this paper is to assess the impacts of design, porosity, and biodegradation on the mechanical and morphological properties of triply periodic minimal surface (TPMS) scaffolds. The TPMS scaffolds were designed and manufactured with different porosities by using fused deposing modeling (FDM) technique. The biodegradation test on the scaffolds was performed for four and six months. The mechanical properties were assessed employing ASTM standard compression test and an in-situ mechanical testing stage. Microcomputed tomography (Micro-CT) technique was used to investigate detailed morphological properties of the scaffolds in 3D. Results indicate that the Schwarz-D scaffolds exhibit the highest compressive strength in lower porosity scaffolds but lose mechanical properties when the porosity was increased. On the contrary, Gyroid scaffolds maintain their strength as the porosity was increased. In addition, Gyroid scaffolds preserve a higher percentage of their compressive strength after six months of biodegradation. It was also observed that biodegradation phenomenon transformed the mechanical failure mode of the scaffolds from ductile to brittle. Morphological analysis of the scaffolds revealed detailed information, which support and clarify the observed variations in the mechanical properties.

Milk fermented with Lactobacillus rhamnosus R0011 induces a regulatory cytokine profile in LPS-challenged U937 and THP-1 macrophages.

Fermented dairy products have become attractive functional foods for the delivery of probiotics and their biologically active metabolites. The aim of this study was to examine the immunomodulatory activity of milk fermented with the probiotic lactic acid bacterium Lactobacillus rhamnosus R0011 (LrF) on macrophages challenged with lipopolysaccharide (LPS), a potent pro-inflammatory stimulus. To this end, human THP-1 or U937 monocytes were differentiated into resting macrophages then stimulated with LPS and co-incubated with the LrF or with milk controls. Levels of pro-inflammatory and immunoregulatory cytokines were determined by enzyme-linked immunosorbent assays. Culturing of LPS-stimulated U937 macrophages with either the whole or filtered LrF resulted in an increase in Interleukin (IL)-1Ra production relative to the negative control. THP-1 macrophages cultured with the LrF demonstrated an increase in LPS-induced IL-10 and IL-1ß production, while production of LPS-induced IL-6, sCD54, IL-8, IL-1ß, TNF-α, IL-12p70 and Transforming Growth Factor-ß (TGF-ß) was unaffected. Further, the LrF induced the expression of DC-SIGN and CD206, markers of immunoregulatory M2 macrophage polarization, in LPS-challenged THP-1 macrophages. Taken together, milk fermented with L. rhamnosus R0011 increased regulatory cytokine production from LPS-challenged U937 and THP-1 macrophages, while simultaneously up-regulating the production of IL-1ß and expression of DC-SIGN and CD206, a profile characteristic of polarization into the immunoregulatory M2 macrophage phenotype.

Disrupting prolonged sitting reduces IL-8 and lower leg swell in active young adults.

BACKGROUND: Evidence suggests that disrupting prolonged bouts of sitting with short bouts of physical activity can significantly reduce blood glucose and improve insulin sensitivity; however, limited research is available on the impact of such disruptions on inflammation and swelling. The purpose of this study was to determine whether short bouts of exercise performed each hour during a 4 h sitting session were able to negate the effects of prolonged sitting (PS) on several cardiometabolic outcomes. METHODS: Eligible participants (n = 10) attended two laboratory sessions: PS (uninterrupted sitting for 4 h) and disrupted sitting (DS; 4 h sitting session disrupted by 3 min of exercise each hour (60-s warm-up at 50 W, 5 s of unloaded cycling, 20-s sprint at 5% body weight, and 95-s cool-down at 50 W)). The exercise bouts were performed at minute 60, 120, and 180. Blood and saliva samples, and measures of heart rate and blood pressure were assessed before (T1) and after (T2) each session; leg swell was measured continuously. RESULTS: Concentrations of salivary IL-8 increased during PS (T1: 0.19 ± 0.32; T2: 0.50 ± 1.00 pg/µg of protein) but decreased during DS (T1: 0.41 ± 0.23; T2: 0.22 ± 0.11 pg/µg of protein, d: 0.51, p = 0.002). Leg swell increased and plateaued in PS, but was attenuated during DS. CONCLUSION: It appears that short bouts of exercise significantly reduce swelling in the lower leg and IL-8 levels in the saliva, indicating that even among healthy, active, young adults, disrupting prolonged sitting can significantly reduce swelling and systemic inflammation.

Suppression of Intestinal Epithelial Cell Chemokine Production by Lactobacillus rhamnosus R0011 and Lactobacillus helveticus R0389 Is Mediated by Secreted Bioactive Molecules.

Host intestinal epithelial cells (IEC) present at the gastrointestinal interface are exposed to pathogenic and non-pathogenic bacteria and their products. Certain probiotic lactic acid bacteria (LAB) have been associated with a range of host-immune modulatory activities including down-regulation of pro-inflammatory gene expression and cytokine production by IEC, with growing evidence suggesting that these bacteria secrete bioactive molecules with immunomodulatory activity. The aim of this study was to determine whether two lactobacilli with immunomodulatory activity [Lactobacillus rhamnosus R0011 (Lr) and Lactobacillus helveticus R0389 (Lh)], produce soluble mediators able to influence IEC responses to Pattern Recognition Receptor (PRR) ligands and pro-inflammatory cytokines [Tumor Necrosis Factor α (TNFα), Interleukin-1ß (IL-1ß)], signals inducing IEC chemokine production during infection. To this end, the effects of cell-free supernatants (CFS) from Lr and Lh on IEC production of the pro-inflammatory chemokines interleukin (IL)-8 and cytokine-induced neutrophil chemoattractant 1 (CINC-1) induced by a range of host- or pathogen-derived pro-inflammatory stimuli were determined, and the impact on human HT-29 IEC and a primary IEC line (rat IEC-6) was compared. The Lr-CFS and Lh-CFS did not significantly modulate basal IL-8 production from HT-29 IECs or CINC-1 production from IEC-6 cells. However, both Lr-CFS and Lh-CFS significantly down-regulated IL-8 production from HT-29 IECs challenged with varied PRR ligands. Lr-CFS and Lh-CFS had differential effects on PRR-induced CINC-1 production by rat IEC-6 IECs, with no significant down-regulation of CINC-1 observed from IEC-6 IECs cultured with Lh-CFS. Further analysis of the Lr-CFS revealed down-regulation of IL-8 production induced by the pro-inflammatory cytokines IL-1ß and TNFα Preliminary characterization of the bioactive constituent(s) of the Lr-CFS indicates that it is resistant to treatment with DNase, RNase, and an acidic protease, but is sensitive to alterations in pH. Taken together, these results indicate that these lactobacilli secrete bioactive molecules of low molecular weight that may modulate host innate immune activity through interactions with IEC.

Nutritional genomics and dietetic professional practice.

Nutrigenomics is concerned with the role of nutrients in gene expression, and nutrigenetics is the study of how genetic variants or polymorphisms (mutations) can affect responses to nutrients; nutritional genomics is the umbrella term. Nutritional genomics can be expected to revolutionize the way dietitians and other health professionals identify people with chronic diseases and treat those diseases. Understanding the science of nutritional genomics is important to dietitians and other health professionals because major scientific advancements such as this usually have a significant impact on ethics, policy, and practice. Blood lipid profiles are one area in which nutritional genomics has quickly advanced knowledge. New knowledge is available on blood lipid profiles and associated conditions, such as obesity and type 2 diabetes. New technology has also had an impact on policy and practice issues, and ethics is an important issue to consider.