Dietary Flaxseed and Flaxseed Oil Differentially Modulate Aspects of the Microbiota Gut-Brain Axis Following an Acute Lipopolysaccharide Challenge in Male C57Bl/6 Mice.

The microbiota gut-brain axis (mGBA) is an important contributor to mental health and neurological and mood disorders. Lipopolysaccharides (LPS) are endotoxins that are components of Gram-negative bacteria cell walls and have been widely shown to induce both systemic and neuro-inflammation. Flaxseed (Linum usitatissimum) is an oilseed rich in fibre, n3-poly-unsaturated fatty acid (alpha-linolenic acid (ALA)), and lignan, secoisolariciresinol diglucoside, which all can induce beneficial effects across varying aspects of the mGBA. The objective of this study was to determine the potential for dietary supplementation with flaxseed or flaxseed oil to attenuate LPS-induced inflammation through modulation of the mGBA. In this study, 72 5-week-old male C57Bl/6 mice were fed one of three isocaloric diets for 3 weeks: (1) AIN-93G basal diet (BD), (2) BD + 10% flaxseed (FS), or (3) BD + 4% FS oil (FO). Mice were then injected with LPS (1 mg/kg i.p) or saline (n = 12/group) and samples were collected 24 h post-injection. Dietary supplementation with FS, but not FO, partially attenuated LPS-induced systemic (serum TNF-α and IL-10) and neuro-inflammation (hippocampal and/or medial prefrontal cortex IL-10, TNF-α, IL-1ß mRNA expression), but had no effect on sickness and nest-building behaviours. FS-fed mice had enhanced fecal microbial diversity with increased relative abundance of beneficial microbial groups (i.e., Lachnospiraceae, Bifidobacterium, Coriobacteriaceae), reduced Akkermansia muciniphila, and increased production of short-chain fatty acids (SCFAs), which may play a role in its anti-inflammatory response. Overall, this study highlights the potential for flaxseed to attenuate LPS-induced inflammation, in part through modulation of the intestinal microbiota, an effect which may not be solely driven by its ALA-rich oil component.

Effect of sodium phosphate supplementation on repeated high-intensity cycling efforts.

Limited research has investigated how sodium phosphate supplementation affects exercise performance typical of athletic competition and whether any effects linger in the short term. This study examined the effect of sodium phosphate supplementation on a cycling protocol consisting of repeated-sprint (4 sets of 6 × 15 s) and time-trial (2 × 5 min) efforts on day 1 and 4 post-loading. Trained male cyclists (VO(2peak) 5.3 L · min⁻¹) were randomised to 6 days of sodium phosphate supplementation (50 mg · kg·fat-free-mass⁻¹ · day⁻¹; n = 7) or placebo (n = 10). Performance was assessed at baseline and 1 and 4 days post-supplementation on an air-braked cycle ergometer. Compared with baseline, the sodium phosphate group recorded significantly improved (P < 0.05) work and mean power output values in both the sprint (baseline, 259 kJ/719 W; day 1, 271 kJ/754 W; day 4, 271 kJ/753 W) and time-trial (baseline, 225 kJ/374 W; day 1, 235 kJ/398 W; day 4, 236 kJ/393 W) aspects of the performance test post-loading. In the placebo group, no differences (P > 0.05) in total work or power output were noted in response to supplementation. In summary, sodium phosphate supplementation improved repeated-sprint and time-trial cycling efforts both 1 and 4 days post-loading in trained cyclists.

Polyphenol-rich grape powder extract (GPE) attenuates inflammation in human macrophages and in human adipocytes exposed to macrophage-conditioned media.

BACKGROUND: Obesity-associated inflammation is characterized by an increased abundance of macrophages (MPhis) in white adipose tissue (WAT), leading to the production of inflammatory cytokines, chemokines and prostaglandins (PGs) that can cause insulin resistance. Grape powder extract (GPE) is rich in phenolic phytochemicals that possess anti-oxidant and anti-inflammatory properties. OBJECTIVE: We examined the ability of GPE to prevent lipopolysaccharide (LPS)-mediated inflammation in human MPhis and silence the cross-talk between human MPhis and adipocytes. DESIGN: We investigated the effect of GPE pretreatment on LPS-mediated activation of mitogen activated protein kinases (MAPKs), nuclear factor kappa B (NF-kappaB) and activator protein-1 (AP-1), and induction of inflammatory genes in human MPhis (that is, differentiated U937 cells). In addition, we determined the effect of GPE pretreatment of MPhis on inflammation and insulin resistance in primary human adipocytes incubated with LPS-challenged MPhi-conditioned medium (MPhi-CM). METHODS AND RESULTS: Pretreatment of MPhis with GPE attenuated LPS-induction of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and IL-1beta; chemokines, such as IL-8 and interferon-gamma inducible protein-10 (IP-10); and a marker of PG production, cyclooxygenase-2 (COX-2). Grape powder extract also attenuated LPS activation of MAPKs, NF-kappaB and AP-1 (c-Jun), as evidenced by decreased (1) phosphorylation of c-Jun NH(2)-terminal kinase (JNK) and p38; (2) degradation of IkappaBalpha and activation of an NF-kappaB reporter construct; and (3) phosphorylation of c-Jun and Elk-1. Using LPS-challenged MPhi-CM, GPE pretreatment attenuated MPhi-mediated inflammatory gene expression, activation of an NF-kappaB reporter and suppression of insulin-stimulated glucose uptake in human adipocytes. CONCLUSION: Collectively, these data demonstrate that GPE attenuates LPS-mediated inflammation in MPhis, possibly by decreasing the activation of MAPKs, NF-kappaB and AP-1, and that GPE decreases the capacity of LPS-stimulated MPhis to inflame adipocytes and cause insulin resistance.

Effect of hydrotherapy on recovery from fatigue.

The present study investigated the effects of three hydrotherapy interventions on next day performance recovery following strenuous training. Twelve cyclists completed four experimental trials differing only in 14-min recovery intervention: cold water immersion (CWI), hot water immersion (HWI), contrast water therapy (CWT), or passive recovery (PAS). Each trial comprised five consecutive exercise days of 105-min duration, including 66 maximal effort sprints. Additionally, subjects performed a total of 9-min sustained effort (time trial - TT). After completing each exercise session, athletes performed one of four recovery interventions (randomly assigned to each trial). Performance (average power), core temperature, heart rate (HR), and rating of perceived exertion (RPE) were recorded throughout each session. Sprint (0.1 - 2.2 %) and TT (0.0 - 1.7 %) performance were enhanced across the five-day trial following CWI and CWT, when compared to HWI and PAS. Additionally, differences in rectal temperature were observed between interventions immediately and 15-min post-recovery; however, no significant differences were observed in HR or RPE regardless of day of trial/intervention. Overall, CWI and CWT appear to improve recovery from high-intensity cycling when compared to HWI and PAS, with athletes better able to maintain performance across a five-day period.

The effect of glucosamine supplementation on people experiencing regular knee pain.

OBJECTIVE: The purpose of this study was to examine the effects of oral glucosamine supplementation on the functional ability and degree of pain felt by individuals who had regular knee pain, most likely due to previous articular cartilage damage, and possibly osteoarthritis. METHODS: Subjects were randomly supplemented with either glucosamine (G) (n=24) or placebo (P) (lactose) (n=22) for 12 weeks at a dose of 2,000 mg per day. Over this period, four testing sessions were conducted, with changes in knee pain and function assessed by clinical and functional tests, (joint line palpation, a 3 metre "duck walk" and a repeated, walking stair climb), two questionnaires (the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Knee Pain Scale (KPS)) and participant subjective evaluations. RESULTS: The clinical and functional test scores improved with time (main effects: p<0.05, p<0.01) but there were no significant differences between the two groups. The questionnaire results also recorded a significant main effect for time (p<0.05), but the glucosamine group was found to have significantly better KOOS quality of life scores at week eight and 12 (p<0.05), and lower KPS scores (p<0.05) at week eight than the placebo group. On self report evaluations of changes across the 12 week supplementation period, 88% (n=21) of the glucosamine group reported some degree of improvement in their knee pain versus only 17% (n=3) in the placebo group. CONCLUSIONS: These results suggest that glucosamine supplementation can provide some degree of pain relief and improved function in persons who experience regular knee pain, which may be caused by prior cartilage injury and/or osteoarthritis. The trends in the results also suggest that, at a dosage of 2,000 mg per day, the majority of improvements are present after eight weeks.

Pre-exercise oral creatine ingestion does not improve prolonged intermittent sprint exercise in humans.

BACKGROUND: This investigation determined whether pre-exercise oral Cr ingestion could enhance prolonged intermittent sprint exercise performance. EXPERIMENTAL DESIGN: a randomised, double-blind crossover design was employed. SETTING: testing was performed at the Western Australian Institute of Sport and participants were monitored and treated by both scientific and medical personnel. PARTICIPANTS: eight active, but not well-trained males with a background in multiple-sprint based sports acted as subjects for this investigation. INTERVENTIONS: subjects ingested either 15 g Cr.H2O or placebo 120 min and 60 min prior to the start of an 80-min maximal sprint cycling task (10 sets of multiple 6-sec sprints with varying active recoveries). Subjects were retested 14 days later, being required to ingest the alternate supplement and repeat the exercise test. MEASURES: performance variables (work done and peak power) were obtained throughout the exercise challenge. Muscle biopsies (vastus lateralis) were raised to a peak of 2348+/-223 micromol x l(-1) prior to the commencement of exercise after Cr ingestion. There were no significant changes in any cycling performance parameters following Cr ingestion, although blood La- was significantly lower (p<0.05) than placebo at all time points during were taken preexercise as well as immediately and 3 min post-exercise in order to determine concentrations of ATP, PCr, Cr, La- and glycogen. Venous blood was drawn prior to and on four occasions during the exercise test, and analysed for Cr, NH3+, La- and pH. RESULTS: Serum Cr concentrations exercise, and plasma NH3+ accumulation was also significantly reduced (p<0.05) in the Cr condition, but only in the second half of the 80-min exercise test. Muscle ATP and TCr levels as well as postexercise PCr replenishment were unaffected following Cr administration. CONCLUSIONS: The data suggest that although the pre-exercise ingestion of a large Cr dose was shown to have some impact on blood borne metabolites, it does not improve maximal prolonged intermittent sprint exercise performance, possibly due to an insufficient time allowed for uptake of serum Cr by skeletal muscle to occur. Therefore, this form of loading does not provide an alternative method of Cr supplementation to the traditional five-day supplementation regimes established by previous research.

Effect of Vitamin C and E supplementation on biochemical and ultrastructural indices of muscle damage after a 21 km run.

This study investigated whether 4 weeks of daily supplementation with 500 or 1000 mg of Vitamin C and 500 or 1000 IU of Vitamin E could modify biochemical and ultrastructural indices of muscle damage following a 21 km run. Fifteen experienced male distance runners were divided into two groups (vitamin or placebo) and received supplementation for four weeks before completing the first 21 km run in as fast a time as possible. A four-week "washout" period followed before the subjects crossed over and received the alternate supplement for the next four weeks. They then completed a second 21 km run. Before, immediately after and 24 h after each run venous blood samples were taken and analysed for serum creatine kinase, myoglobin, malondialdehyde and vitamin C and E (before-samples only) concentrations. A subgroup of six subjects also had muscle biopsy (gastrocnemius) samples taken 24 h before and 24 h after each 21 km run, which were later analysed by electron microscopy. The two dosages of supplementation produced similar results, so a single vitamin group was formed for further analysis of results. Significant increases (p < 0.05) in creatine kinase and myoglobin, but not in malondialdehyde, were found post-run in both groups. However, no significant differences were found between the vitamin and placebo groups for creatine kinase, myoglobin and malondialdehyde concentrations recorded after the 21 km runs. A qualitative ultrastructural examination of pre-run muscle samples revealed changes consistent with endurance training, but little further change was seen after the 21 km run in either the vitamin or placebo groups. It was concluded that vitamin C and E supplementation (500 or 1000 mg or IU per day) for four weeks does not reduce either biochemical or ultrastructural indices of muscle damage in experienced runners after a half marathon.

Proposed phytic acid standard including a method for its analysis.

A method is described that accurately and rapidly quantifies the free and total phosphorous content of a commercially available, purified, phytic acid preparation. This allows its use as a standard for phytic acid determinations in foods. The method involves a wet ashing step followed by phosphorous measurement with a 1-amino-2-naphthol-4-sulfonic acid-molybdate reagent in a microplate reader at 660 nm. The procedure can be performed in 3 h with as little as 50 mg sample.

Effect of creatine loading on long-term sprint exercise performance and metabolism.

PURPOSE: This study examined whether creatine (Cr) supplementation could enhance long-term repeated-sprint exercise performance of approximately 80 min in duration. METHODS: Fourteen active, but not well-trained, male subjects initially performed 10 sets of either 5 or 6 x 6 s maximal bike sprints, with varying recoveries (24, 54, or 84 s between sprints) over a period of 80 min. Work done (kJ) and peak power (W) were recorded for each sprint, and venous blood was collected preexercise and on four occasions during the exercise challenge. Muscle biopsies (vastus lateralis) were obtained preexercise as well as 0 min and 3 min postexercise. Subjects were then administered either 20 g.d-1 Cr.H2O (N = 7) or placebo (N = 7) for 5 d. Urine samples were collected for each 24 h of the supplementation period. Subjects were then retested using the same procedures as in test 1. RESULTS: Total work done increased significantly (P < 0.05) from 251.7 +/- 18.4 kJ presupplementation to 266.9 +/- 19.3 kJ (6% increase) after Cr ingestion. No change was observed for the placebo group (254.0 +/- 10.4 kJ to 252.3 +/- 9.3 kJ). Work done also improved significantly (P < 0.05) during 6 x 6 s sets with 54-s and 84-s recoveries and approached significance (P = 0.052) in 5 x 6 s sets with 24-s recovery in the Cr condition. Peak power was significantly increased (P < 0.05) in all types of exercise sets after Cr loading. No differences were observed for any performance variables in the placebo group. Resting muscle Cr and PCr concentrations were significantly elevated (P < 0.05) after 5 d of Cr supplementation (Cr: 48.9%; PCr: 12.5%). Phosphocreatine levels were also significantly higher (P < 0.05) immediately and 3 min after the completion of exercise in the Cr condition. CONCLUSION: The results of this study indicate that Cr ingestion (20 g.day-1 x 5 d) improved exercise performance during 80 min of repeated-sprint exercise, possibly due to an increased TCr store and improved PCr replenishment rate.

The effect of intramuscular iron injections on serum ferritin levels and physical performance in elite netballers.

The purpose of this study was to determine the effect of iron supplementation by intramuscular injection on both serum ferritin (SF) levels and exercise performance in iron depleted, non-anaemic elite female netballers. Fifteen iron depleted (Serum Ferritin <40 ug x L(-1). Haemoglobin >125 g x L(-1)) subjects (19+/-3 y) first performed their routine test battery: a vertical jump test, a 10s power and 5x6s repeat sprint test on a cycle ergometer and a 20m multi-stage shuttle run. Subjects were matched on the basis of height, mass, and playing position and then assigned to either a Ferritin Group (FG) or Placebo Group (PG) (single blind design). Subjects then underwent a course of 5x2ml intramuscular injections of either Ferrum H (FG) or normal saline (PG) over a period of 8-10 days before repeating the blood and physical performance tests. Five and 10 days following supplementation, SF levels in the FG increased significantly from baseline levels (P<0.05) and were also significantly greater than levels measured in the PG (P<0.01). Haemoglobin levels remained unchanged in both groups. All test scores remained unchanged from baseline values and were not different between the two groups. These results demonstrate that a course of 5x2ml intramuscular iron injections significantly increased SF concentration within 2 weeks without increasing Hb levels, but this rapid elevation did not enhance the physical performance in selected tests of iron depleted, non-anaemic athletes.

Parthenolide content and bioactivity of feverfew (Tanacetum parthenium (L.) Schultz-Bip.). Estimation of commercial and authenticated feverfew products.

Three physicochemical methods (HPLC, NMR spectroscopy, and HPLC of a derivative) have been used to measure parthenolide in authenticated Tanacetum parthenium (feverfew) and in several commercial purported feverfew products. A bioassay based on inhibition of the secretory activity of blood platelets by extracts of feverfew in comparison with parthenolide was also used. Similar results were obtained for all three physicochemical assays and also for the bioassay. Thus different methodologies yield consistent values for parthenolide content of feverfew preparations. Parthenolide appears to be mainly responsible for the antisecretory effects of extracts of feverfew. Authenticated Tanacetum parthenium grown in the UK contained a high level of parthenolide in leaves, flowering tops and seeds but a low level in stalks and roots. The level of parthenolide in powdered leaf material fell during storage. The purported feverfew products varied widely in their parthenolide content and in some products parthenolide was not detected. Possible reasons for the variation in parthenolide content are discussed. Since therapeutic efficacy has only been demonstrated for preparations of feverfew that contain parthenolide, it is suggested that manufacturers of feverfew products should use measurements of parthenolide as a means of standardization and quality control.

Anaesthesia for day-care surgery: a symposium (III). Anaesthesia for adult surgical out-patients.

This discussion is based on the experience of the Phoenix Surgicenter, where over 60,000 patients have been anaesthetized since 1970. Patients accepted for out-patient surgery are ASA Status I or II, although status III patients may be included if their co-existing disability is under excellent control. Eighty-five per cent of adult patients receive general anaesthesia. A wide variety of local and regional anaesthetic techniques may be used. Efforts during recovery are directed towards preparing the patient for discharge in a "home ready" condition for safe handling by attending relatives. The common complications have been postoperative nausea or emesis and hypotension. The hospital transfer rate has been 0.2 per cent.