Anticancer actions of carnosine in cellular models of prostate cancer.

Treatments for organ-confined prostate cancer include external beam radiation therapy, radical prostatectomy, radiotherapy/brachytherapy, cryoablation and high-intensity focused ultrasound. None of these are cancer-specific and are commonly accompanied by side effects, including urinary incontinence and erectile dysfunction. Moreover, subsequent surgical treatments following biochemical recurrence after these interventions are either limited or affected by the scarring present in the surrounding tissue. Carnosine (ß-alanyl-L-histidine) is a histidine-containing naturally occurring dipeptide which has been shown to have an anti-tumorigenic role without any detrimental effect on healthy cells; however, its effect on prostate cancer cells has never been investigated. In this study, we investigated the effect of carnosine on cell proliferation and metabolism in both a primary cultured androgen-resistant human prostate cancer cell line, PC346Flu1 and murine TRAMP-C1 cells. Our results show that carnosine has a significant dose-dependent inhibitory effect in vitro on the proliferation of both human (PC346Flu1) and murine (TRAMP-C1) prostate cancer cells, which was confirmed in 3D-models of the same cells. Carnosine was also shown to decrease adenosine triphosphate content and reactive species which might have been caused in part by the increase in SIRT3 also shown after carnosine treatment. These encouraging results support the need for further human in vivo work to determine the potential use of carnosine, either alone or, most likely, as an adjunct therapy to surgical or other conventional treatments.

Bone mineral density in high-level endurance runners: Part B-genotype-dependent characteristics.

PURPOSE: Inter-individual variability in bone mineral density (BMD) exists within and between endurance runners and non-athletes, probably in part due to differing genetic profiles. Certainty is lacking, however, regarding which genetic variants may contribute to BMD in endurance runners and if specific genotypes are sensitive to environmental factors, such as mechanical loading via training. METHOD: Ten single-nucleotide polymorphisms (SNPs) were identified from previous genome-wide and/or candidate gene association studies that have a functional effect on bone physiology. The aims of this study were to investigate (1) associations between genotype at those 10 SNPs and bone phenotypes in high-level endurance runners, and (2) interactions between genotype and athlete status on bone phenotypes. RESULTS: Female runners with P2RX7 rs3751143 AA genotype had 4% higher total-body BMD and 5% higher leg BMD than AC + CC genotypes. Male runners with WNT16 rs3801387 AA genotype had 14% lower lumbar spine BMD than AA genotype non-athletes, whilst AG + GG genotype runners also had 5% higher leg BMD than AG + GG genotype non-athletes. CONCLUSION: We report novel associations between P2RX7 rs3751143 genotype and BMD in female runners, whilst differences in BMD between male runners and non-athletes with the same WNT16 rs3801387 genotype existed, highlighting a potential genetic interaction with factors common in endurance runners, such as high levels of mechanical loading. These findings contribute to our knowledge of the genetic associations with BMD and improve our understanding of why some runners have lower BMD than others.

Bone mineral density in high-level endurance runners: part A-site-specific characteristics.

PURPOSE: Physical activity, particularly mechanical loading that results in high-peak force and is multi-directional in nature, increases bone mineral density (BMD). In athletes such as endurance runners, this association is more complex due to other factors such as low energy availability and menstrual dysfunction. Moreover, many studies of athletes have used small sample sizes and/or athletes of varying abilities, making it difficult to compare BMD phenotypes between studies. METHOD: The primary aim of this study was to compare dual-energy X-ray absorptiometry (DXA) derived bone phenotypes of high-level endurance runners (58 women and 45 men) to non-athletes (60 women and 52 men). Our secondary aim was to examine the influence of menstrual irregularities and sporting activity completed during childhood on these bone phenotypes. RESULTS: Female runners had higher leg (4%) but not total body or lumbar spine BMD than female non-athletes. Male runners had lower lumbar spine (9%) but similar total and leg BMD compared to male non-athletes, suggesting that high levels of site-specific mechanical loading was advantageous for BMD in females only and a potential presence of reduced energy availability in males. Menstrual status in females and the number of sports completed in childhood in males and females had no influence on bone phenotypes within the runners. CONCLUSION: Given the large variability in BMD in runners and non-athletes, other factors such as variation in genetic make-up alongside mechanical loading probably influence BMD across the adult lifespan.

Exercise interventions for weight management during pregnancy and up to 1 year postpartum among normal weight, overweight and obese women: a systematic review and meta-analysis.

BACKGROUND: The prevalence of excessive gestation weight gain, extended postpartum weight retention and pregravid obese women is increasing and is associated with numerous adverse health outcomes. OBJECTIVE: To review the evidence from studies employing exercise-only interventions for weight management among pregnant and postpartum women. SEARCH STRATEGY: Ten databases were searched for randomised controlled trials conducted during pregnancy or within the 12 months following childbirth and published between 1990 and 2013. SELECTION CRITERIA: There were no restrictions to the type, frequency, duration or intensity of exercise intervention. Interventions not specifically designed to target weight were excluded. The outcomes were a change in body weight (kg) or body mass index (BMI; kg/m(2)). DATA COLLECTION AND ANALYSIS: All data were continuous and were reported as weighted mean differences (WMD), with 95% CIs. Data were analysed with a fixed-effect model and heterogeneity was determined using the I(2) statistic. RESULTS: Five studies were included in this review. Exercise significantly reduced gestational weight gain (WMD=-2.22 kg, CI -3.14 to -1.3, p≤0.00001) and had no significant effect on postpartum weight loss (WMD=-1.74 kg, CI -3.59 to 0.10, p=0.06) or BMI during pregnancy (WMD=-2.8 kg/m(2), CI -5.60 to 0.00, p=0.05) or postpartum (WMD=-0.54 kg/m(2), CI -1.17 to 0.08, p=0.09). CONCLUSIONS: There is currently limited evidence to suggest that exercise can be used to limit maternal gestational weight gain.

Properties of non-coding mutation hotspots as urinary biomarkers for bladder cancer detection.

Mutations at specific hotspots in non-coding regions of ADGRG6, PLEKHS1, WDR74, TBC1D12 and LEPROTL1 frequently occur in bladder cancer (BC). These mutations could function as biomarkers for the non-invasive detection of BC but this remains largely unexplored. Massively-parallel sequencing of non-coding hotspots was applied to 884 urine cell pellet DNAs: 591 from haematuria clinic patients (165 BCs, 426 non-BCs) and 293 from non-muscle invasive BC surveillance patients (29 with recurrence). Urine samples from 142 non-BC haematuria clinic patients were used to optimise variant calling. Non-coding mutations are readily detectable in the urine of BC patients and undetectable, or present at much lower frequencies, in the absence of BC. The mutations can be used to detect incident BC with 66% sensitivity (95% CI 58-75) at 92% specificity (95% CI 88-95) and recurrent disease with 55% sensitivity (95% CI 36-74) at 85% specificity (95% CI 80-89%) using a 2% variant allele frequency threshold. In the NMIBC surveillance setting, the detection of non-coding mutations in urine in the absence of clinically detectable disease was associated with an increased relative risk of future recurrence (RR = 4.62 (95% CI 3.75-5.48)). As urinary biomarkers, non-coding hotspot mutations behave similarly to driver mutations in BC-associated genes and could be included in biomarker panels for BC detection.

Effects of ß-alanine supplementation on exercise performance: a meta-analysis.

Due to the well-defined role of ß-alanine as a substrate of carnosine (a major contributor to H+ buffering during high-intensity exercise), ß-alanine is fast becoming a popular ergogenic aid to sports performance. There have been several recent qualitative review articles published on the topic, and here we present a preliminary quantitative review of the literature through a meta-analysis. A comprehensive search of the literature was employed to identify all studies suitable for inclusion in the analysis; strict exclusion criteria were also applied. Fifteen published manuscripts were included in the analysis, which reported the results of 57 measures within 23 exercise tests, using 18 supplementation regimes and a total of 360 participants [174, ß-alanine supplementation group (BA) and 186, placebo supplementation group (Pla)]. BA improved (P=0.002) the outcome of exercise measures to a greater extent than Pla [median effect size (IQR): BA 0.374 (0.140-0.747), Pla 0.108 (-0.019 to 0.487)]. Some of that effect might be explained by the improvement (P=0.013) in exercise capacity with BA compared to Pla; no improvement was seen for exercise performance (P=0.204). In line with the purported mechanisms for an ergogenic effect of ß-alanine supplementation, exercise lasting 60-240 s was improved (P=0.001) in BA compared to Pla, as was exercise of >240 s (P=0.046). In contrast, there was no benefit of ß-alanine on exercise lasting <60 s (P=0.312). The median effect of ß-alanine supplementation is a 2.85% (-0.37 to 10.49%) improvement in the outcome of an exercise measure, when a median total of 179 g of ß-alanine is supplemented.

Determinants of muscle carnosine content.

The main determinant of muscle carnosine (M-Carn) content is undoubtedly species, with, for example, aerobically trained female vegetarian athletes [with circa 13 mmol/kg dry muscle (dm)] having just 1/10th of that found in trained thoroughbred horses. Muscle fibre type is another key determinant, as type II fibres have a higher M-Carn or muscle histidine containing dipeptide (M-HCD) content than type I fibres. In vegetarians, M-Carn is limited by hepatic synthesis of ß-alanine, whereas in omnivores this is augmented by the hydrolysis of dietary supplied HCD's resulting in muscle levels two or more times higher. ß-alanine supplementation will increase M-Carn. The same increase in M-Carn occurs with administration of an equal molar quantity of carnosine as an alternative source of ß-alanine. Following the cessation of supplementation, M-Carn returns to pre-supplementation levels, with an estimated t1/2 of 5-9 weeks. Higher than normal M-Carn contents have been noted in some chronically weight-trained subjects, but it is unclear if this is due to the training per se, or secondary to changes in muscle fibre composition, an increase in ß-alanine intake or even anabolic steroid use. There is no measureable loss of M-Carn with acute exercise, although exercise-induced muscle damage may result in raised plasma concentrations in equines. Animal studies indicate effects of gender and age, but human studies lack sufficient control of the effects of diet and changes in muscle fibre composition.

The effects of short-term low energy availability, achieved through diet or exercise, on cognitive function in oral contraceptive users and eumenorrheic women.

To date, no research has explored the effects of low energy availability on cognitive performance using dietary and exercise regimens relevant to athletes. Twenty female participants (10 eumenorrheic, 10 oral contraceptive [OC] users) completed three 3-day conditions: 1) controlled-balanced energy availability without exercise (BAL; 45 kcal·kg lean body mass [LBM]-1·day-1); 2) diet-induced low energy availability without exercise (DIET; 15 kcal·kg LBM-1·day-1); and 3) exercise-induced low energy availability (EX; 15 kcal·kg LBM-1·day-1, including 30 kcal·kg LBM-1·day-1 treadmill running at 70% maximal oxygen uptake). A cognitive test battery was completed before and after each 3-day condition. Mental rotation test accuracy improved in the BAL condition, but there was a decline in accuracy in the EX condition (BAL, +2.5%; EX, -1.4%; P = 0.042, d = 0.85). DIET (+1.3%) was not different to BAL or EX (P > 0.05). All other measures of cognitive performance were not affected by condition (P > 0.05) and OC use did not affect cognitive responses (P > 0.05). Accuracy in the mental rotation test was impaired when low energy availability was induced through increased exercise energy expenditure. All other aspects of cognition were unaffected by 3 days of low energy availability through diet or exercise. OC use did not mediate the effect of low energy availability on cognition. Novelty: Cognitive function was not affected by 3 days of diet-induced low energy availability. Only spatial awareness was impaired during 3 days of exercise-induced low energy availability. Reproductive hormones affected spatial awareness independent of energy availability.

The influence of acute exercise on bone biomarkers: protocol for a systematic review with meta-analysis.

BACKGROUND: Bone is a plastic tissue that is responsive to its physical environment. As a result, exercise interventions represent a potential means to influence the bone. However, little is currently known about how various exercise and participant characteristics interact to influence bone metabolism. Acute, controlled, interventions provide an in vivo model through which the acute bone response to exercise can be investigated, typically by monitoring circulating bone biomarkers. Currently, substantial heterogeneity in factors such as study design, quality, exercise, and participant characteristics render it difficult to synthesize and evaluate the available evidence. Using a systematic review and meta-analytic approach, the aim of this investigation is to quantify the effect of an acute exercise bout on circulating bone biomarkers as well as examine the potential factors that may moderate this response, e.g., variation in participant, exercise, and sampling characteristics. METHODS: This protocol was designed in accordance with the PRISMA-P guidelines. Seven databases (MEDLINE, Embase, Sport Discus, Cochrane CENTRAL, PEDro, LILACS, and Ibec) will be systematically searched and supplemented by a secondary screening of the reference lists of all included articles. The PICOS (Population, Intervention, Comparator, Outcomes and Study Design) approach was used to guide the determination of the eligibility criteria. Participants of any age, sex, training, or health status will be considered for inclusion. We will select studies that have measured the bone biomarker response before and after an acute exercise session. All biomarkers considered to represent the bone metabolism will be considered for inclusion, and sensitivity analyses will be conducted using reference biomarkers for the measurement of bone resorption and formation (namely ß-CTX-1 and P1NP). Multi-level, meta-regression models within a Bayesian framework will be used to explore the main effect of acute exercise on bone biomarkers as well as potential moderating factors. The risk of bias for each individual study will be evaluated using a modified version of the Downs and Black checklist while certainty in resultant outcomes will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. DISCUSSION: A better understanding of the bone metabolic response to an acute bout of exercise has the potential to advance our understanding of the mechanisms through which this stimulus impacts bone metabolism, including factors that may moderate this response. Additionally, we will identify current gaps in the evidence base and provide recommendations to inform future research. SYSTEMATIC REVIEW REGISTRATION: This protocol was prospectively registered in the Open Science Framework Registry ( https://osf.io/6f8dz ).

A Comparative Study of Hummingbirds and Chickens Provides Mechanistic Insight on the Histidine Containing Dipeptide Role in Skeletal Muscle Metabolism.

Histidine containing dipeptides (HCDs) have numerous ergogenic and therapeutic properties, but their primary role in skeletal muscle remains unclear. Potential functions include pH regulation, protection against reactive oxygen/nitrogen species, or Ca2+ regulation. In recognition of the challenge of isolating physiological processes in-vivo, we employed a comparative physiology approach to investigate the primary mechanism of HCD action in skeletal muscle. We selected two avian species (i.e., hummingbirds and chickens), who represented the extremes of the physiological processes in which HCDs are likely to function. Our findings indicate that HCDs are non-essential to the development of highly oxidative and contractile muscle, given their very low content in hummingbird skeletal tissue. In contrast, their abundance in the glycolytic chicken muscle, indicate that they are important in anaerobic bioenergetics as pH regulators. This evidence provides new insights on the HCD role in skeletal muscle, which could inform widespread interventions, from health to elite performance.

Extradural spinal juxtafacet (synovial) cysts in three dogs.

Three dogs were presented for investigation of spinal disease and were diagnosed with extradural spinal juxtafacet cysts of synovial origin. Two dogs that were presented with clinical signs consistent with pain in the lumbosacral region associated with bilateral hindlimb paresis were diagnosed using magnetic resonance imaging. Both cysts were solitary and associated with the L6-7 dorsal articulations; both the dogs had a transitional vertebra in the lumbosacral region. A third dog that was presented with progressive paraparesis localised to T3-L3 spinal cord segments and compression of the spinal cord at T13-L1 was diagnosed using myelography. A solitary multiloculated cyst was found at surgery. Decompressive surgery resulted in resolution of the clinical signs in all three dogs. Immunohistological findings indicated that one to two layers of vimentin-positive cells consistent with synovial origin lined the cysts.

Exercise induces a change in plasma fibrinogen concentration: fact or fiction?

This study examined the effect of exercise on plasma fibrinogen concentrations with simultaneous measurements of plasma volume changes. Eight moderately active males aged 26.6+/-3.6 years (mean +/- SD) completed maximal (VO2max) and submaximal (75% VO2max for 30 minutes) exercise trials separated by 7 days. Venous blood samples were obtained at rest, immediately postexercise, and following 30 minutes of recovery. Whole blood was analysed for haematocrit and haemoglobin, while citrated plasma was assayed for fibrinogen levels. Values of haematocrit and haemoglobin before and after exercise were utilised for the estimation of plasma volume changes. Plasma volume decreased (p<0.05) immediately following both maximal (-17.7+/-5.1%) and submaximal (-14.3+/-4.1%) exercise. Exercise resulted in decreased plasma fibrinogen levels (maximal exercise: from 266.3+/-14.5 to 222.2+/-23.9 mg x dL(-1); submaximal exercise: from 239.5+/-45.4 to 209.7+/-42.4 mg x dL(-1)) only when postexercise raw data were corrected for the contraction of plasma volume. It is concluded therefore that changes in plasma volume in response to exercise should be taken into account when interpreting exercise effects on plasma fibrinogen concentration.

Blood hemostasis in exercise and training.

Formation of the blood clot is a slow but normal physiological process occurring as a result of the activation of blood coagulation pathways. Nature's guard against unwanted blood clots is the fibrinolytic enzyme system. In healthy people, there is a delicate dynamic balance between blood clot formation and blood clot dissolution. Available evidence suggests that exercise and physical training evoke multiple effects on blood hemostasis in normal healthy subjects and in patients. A single bout of exercise is usually associated with a transient increase in blood coagulation as evidenced by a shortening of activated partial thromboplastin time (APTT) and increased Factor VIII (FVIII). The rise in FVIII is intensity dependent and continues into recovery. The effects of acute exercise on plasma fibrinogen have yielded conflicting results. Thus, the issue of whether exercise-induced blood hypercoagulability in vitro mirrors an in vivo thrombin generation and fibrin formation remains disputable. Exercise-induced enhancement of fibrinolysis has been repeatedly demonstrated using a wide range of exercise protocols incorporating various exercise intensities and durations. Moderate exercise appears to enhance blood fibrinolytic activity without a concomitant activation of blood coagulation mechanisms, whereas, very heavy exercise induces simultaneous activation of blood fibrinolysis and coagulation. The increase in fibrinolysis is due to a rise in tissue-type plasminogen activator (tPA) and decrease in plasminogen activator inhibitor (PAI). The mechanism of exercise-induced hyperfibrinolysis is poorly understood, and the physiological utility of such activation remains unresolved. Strenuous exercise elicits a transient increase in platelet count, but there are conflicting results concerning the effect of exercise on platelet aggregation and activation. Few comprehensive studies exist concerning the influence of exercise training on blood hemostasis, making future investigation necessary to identify whether there are favorable effects of exercise training on blood coagulation, fibrinolysis, and platelet functions.

Homotypic and heterotypic serum and milk antibody to rotavirus in normal, infected and vaccinated horses.

The homotypic and heterotypic antibody response to rotavirus was determined in three pony mares and their foals. The normal concentrations of anti-rotavirus antibodies in mares' milk and mares' and foals' serum over the first 10 weeks post-partum were measured using IgA, IgG and rotavirus serotype-specific enzyme linked immunosorbent assays. Experimental infection of the foals with serotype 3 equine rotavirus produced a rapid, serotype-specific response which peaked 10 days after infection and a slower heterotypic response which peaked 32 days later. In contrast, vaccination of the mares with an inactivated, adjuvanted serotype 6 bovine rotavirus produced a heterotypic response similar to that of the homotypic response in both serum and milk, although the predominant response in serum was IgG, while in milk it was IgA. These results suggest that non serotype-restricted passive protection of foals against rotavirus may be achieved by parenteral vaccination of mares.

Spinal nephroblastoma in a crossbreed dog.

A three-year-old, male crossbreed dog presented with progressive hindlimb paresis. Magnetic resonance imaging revealed an intramedullary spinal cord lesion of 1.5 cm diameter at the levels of the first and second lumbar vertebrae. Following surgical excision of the mass, there was resolution of the neurological signs. Twelve months later, hindlimb paresis was again evident. A second surgical procedure restored ambulatory status for a further five months before signs recurred and the dog was euthanased. A diagnosis of spinal nephroblastoma was made on the basis of signalment, lesion location and histopathological analysis of biopsy specimens.

Systematic review of randomised controlled trials on exercise interventions for weight management during pregnancy and up to one year postpartum among normal weight, overweight and obese women.

OBJECTIVE: To review the effectiveness of exercise interventions in managing weight among pregnant and postpartum women. METHODS: Ten databases were searched for randomised controlled studies, published between January 1990 and September 2013 that compared an exercise-based weight management intervention with routine care or another type of intervention. There were no restrictions to the type, frequency, duration, intensity or mode of exercise intervention. Interventions not specifically designed to target or affect weight were excluded. Study quality was assessed using the Cochrane Collaboration's tool for assessing risk of bias in randomised trials and the Consolidated Standards of Reporting Trials statement. RESULTS: The combined searches yielded 354 articles. Reasons for study exclusion included but were not limited to; non-randomisation, retrospective study design, duplicates, qualitative/baseline studies, not specifically designed to influence weight, combined intervention and study protocols. Five papers were included in this review (three trials with pregnant women and two trials with postpartum women). Two of the three pregnancy-related studies found that exercise interventions significantly reduced gestational weight gain. In addition, postpartum women in the intervention groups lost significantly more body weight than those in the control groups. CONCLUSIONS: There is a paucity of information on the efficacy of exercise-only interventions for the prevention of excessive gestational weight gain and retention. However, there is some limited evidence to suggest that exercise can be used for these groups to alleviate some of the issues associated with maternal obesity.

Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity.

Muscle carnosine synthesis is limited by the availability of beta-alanine. Thirteen male subjects were supplemented with beta-alanine (CarnoSyn) for 4 wks, 8 of these for 10 wks. A biopsy of the vastus lateralis was obtained from 6 of the 8 at 0, 4 and 10 wks. Subjects undertook a cycle capacity test to determine total work done (TWD) at 110% (CCT(110%)) of their maximum power (Wmax). Twelve matched subjects received a placebo. Eleven of these completed the CCT(110%) at 0 and 4 wks, and 8, 10 wks. Muscle biopsies were obtained from 5 of the 8 and one additional subject. Muscle carnosine was significantly increased by +58.8% and +80.1% after 4 and 10 wks beta-alanine supplementation. Carnosine, initially 1.71 times higher in type IIa fibres, increased equally in both type I and IIa fibres. No increase was seen in control subjects. Taurine was unchanged by 10 wks of supplementation. 4 wks beta-alanine supplementation resulted in a significant increase in TWD (+13.0%); with a further +3.2% increase at 10 wks. TWD was unchanged at 4 and 10 wks in the control subjects. The increase in TWD with supplementation followed the increase in muscle carnosine.

Metabolic and physiological effects of ingesting extracts of bitter orange, green tea and guarana at rest and during treadmill walking in overweight males.

OBJECTIVE: This study examined the acute effects of ingesting a widely used commercial formula containing extracts of bitter orange, green tea and guarana (Gx) on the metabolic rate and substrate utilisation in overweight, adult males at rest (study 1) and during treadmill walking (study 2). SUBJECTS: Two different groups of 10 sedentary males with more than 20% body fat participated in studies 1 and 2. DESIGN: In each study, subjects participated in two experimental trials during which they were given two 500 mg capsules containing either Gx or a placebo (P) in a counterbalanced double-blind manner. Doses of the main active ingredients were 6 mg of synephrine, 150 mg caffeine and 150 mg catechin polyphenols. MEASUREMENTS: In study 1, subjects completed 7 h supine rest with baseline measures taken during the first hour, with expired gases, blood pressure, heart rate and venous blood being collected every 30 min for the remaining 6 h following ingestion of Gx or P. In study 2, subjects exercised for 60 min at 60% heart rate reserve following ingestion of Gx or P 1 h previously. Venous blood samples were collected twice at rest and at 5, 10, 15, 20, 30, 40, 50 and 60 min, with expired gas measurements taken at 4, 9, 14, 19, 29, 39, 49 and 59 min. In both studies, venous blood was analysed for NEFA, glycerol, glucose and lactate concentrations, while expired gases were used to calculate ATP production from carbohydrate and NEFA, as well as the total substrate utilised. RESULTS AND CONCLUSION: The results did not show any significant effect of Gx ingestion on total ATP utilisation during 6 h rest or during 60 min treadmill walking. Changes were observed in the relative contributions of CHO and NEFA oxidation to ATP production in both studies, such that there was an increase in ATP production from CHO and a decrease from NEFA. The increase in CHO oxidation was shown to be as high as 30% at rest.