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Skeletal muscle wasting is a common hallmark of (late stage) cancer, which is also called cancer cachexia. Cancer cachexia is due to the (selfish) tumour present in the body, which activates many processes in multiple organs eventually leading to the loss of muscle mass. When we unravel the mechanisms involved, treatments to prevent or counteract the cancer cachexia can be developed.In this thesis the impact of vibration training was tested in an animal model of cancer cachexia. Analysis of transcriptome data revealed that vibration training reduced the tumour-related effects in muscle. These effects were associated with an attenuation of the upregulation of the proteasome pathway in the soleus muscle. We also found that the oxidative phosphorylation pathway was among the most abundant downregulated pathways in muscle of the cachectic animals.Secondly, muscle cells were used to investigate the effects of secreted immune signalling molecules by the tumour cells on muscle development. Global gene expression, measured by RNA sequencing, showed a significant upregulation of immune pathways. Oxidative phosphorylation was again found in the top downregulated pathways.Next to this, the role of mitochondria in cachexia were studied. Mitochondria are an important part of the (muscle) cells, as they generate most of the energy molecules. Our literature analysis showed that the expression of genes involved in mitochondrial fusion, fission, ATP production and mitochondrial density is decreased, while that of genes involved in reactive oxygen species (ROS) detoxification and mitophagy is increased. When investigating the effects of secreted molecules by the tumour cells on muscle development we found that about 70% of the significant differentially expressed MitoCarta genes were downregulated. In contrast, the whole genome expression consisted mainly of upregulated genes. The in vivo data turned out to have an overlap with the in vitro data, eight MitoCarta genes were found in b

Gamma-aminobutyric acid (GABA) and its precursor glutamate play signaling roles in a range of tissues. Both function as neurotransmitters in the central nervous system, but they also modulate pancreatic and immune functioning, for example. Besides endogenous production, both compounds are found in food products, reaching relatively high levels in tomatoes. Recent studies in rodents suggest beneficial effects of oral GABA on glucose homeostasis and blood pressure. However, the bioavailability from food remains unknown. We studied the bioavailability of GABA and glutamate from tomatoes relative to a solution in water. After a fasting blood sample was taken, eleven healthy men randomly received 1 liter of 4 different drinks in a cross-over design with a one-week interval. The drinks were a solution of 888 mg L−1 GABA, a solution of 3673 mg L−1 glutamate, pureed fresh tomatoes and plain water as the control. Following intake, 18 blood samples were taken at intervals for 24 hours. Plasma GABA and glutamate concentrations were determined by ultra-pressure liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). Fasting plasma GABA and glutamate concentrations were found to be 16.71 (SD 2.18) ng mL−1 and 4626 (SD 1666) ng mL−1, respectively. Fasting GABA levels were constant (5.8 CV%) between individuals, while fasting glutamate levels varied considerably (23.5 CV%). GABA from pureed tomatoes showed similar bioavailability to that of a solution in water. For glutamate, the absorption from pureed tomatoes occurred more slowly as seen from a longer tmax (0.98 ± 0.14 h vs. 0.41 ± 0.04 h, P = 0.003)and lower Cmax (7815 ± 627 ng mL−1 vs. 16 420 ± 2778 ng mL−1, P = 0.006). These data suggest that GABA is bioavailable from tomatoes, and that food products containing GABA could potentially induce health effects similar to those claimed for GABA supplements. The results merit further studies on the bioavailability of GABA from other food products and the health eff

Item does not contain fulltext, BACKGROUND: We investigated whether preoperative and postoperative levels of inflammation markers, which have mechanistically been linked to colorectal cancer progression, were associated with recurrence and all-cause mortality in patients with colorectal cancer. METHODS: Data of two prospective cohort studies were used. For the current analysis, patients with stage I to III colorectal cancer were considered. Data on inflammation [IL6, IL8, IL10, TNFα, high-sensitivity C-reactive protein (hsCRP), and a combined inflammatory z-score] were available for 747 patients before surgery and for 614 patients after surgery. The associations between inflammation marker levels and colorectal cancer recurrence and all-cause mortality were examined using multivariable Cox proportional hazard regression models, considering patient characteristics and clinical and lifestyle factors. RESULTS: Higher preoperative and postoperative hsCRP levels were associated with a higher risk of recurrence [HR(per doubling) (95% CI), 1.15 (1.02-1.30) and 1.34 (1.16-1.55)] and all-cause mortality [HR(per doubling) (95% CI) 1.13 (1.01-1.28) and 1.15 (0.98-1.35)]. A doubling in IL8 levels (preoperative levels HR = 1.23; 95% CI, 1.00-1.53 and postoperative levels HR = 1.61; 95% CI, 1.23-2.12) and a higher combined inflammatory z-score (preoperative HR(per doubling) = 1.39; 95% CI, 1.03-1.89 and postoperative HR(per doubling) = 1.56; 95% CI, 1.06-2.28) were associated with a higher risk of all-cause mortality, but not recurrence. No associations between IL6, IL10, and TNFα and recurrence or all-cause mortality were observed. CONCLUSIONS: Preoperative and postoperative levels of specific inflammation markers were associated with recurrence and/or all-cause mortality. IMPACT: The complex role of inflammation in cancer recurrence merits further elucidation by investigating local inflammation at the tumor site.

Contains fulltext : 230359.pdf (publisher's version ) (Open Access)

Contains fulltext : 245175.pdf (Publisher’s version ) (Open Access), Metabolic syndrome increases the risk of vascular dementia and other neurodegenerative disorders. Recent studies underline that platelets play an important role in linking peripheral with central metabolic and inflammatory mechanisms. In this narrative review, we address the activation of platelets in metabolic syndrome, their effects on neuronal processes and the role of the mediators (e.g., serotonin, platelet-derived growth factor). Emerging evidence shows that nutritional compounds and their metabolites modulate these interactions-specifically, long chain fatty acids, endocannabinoids and phenolic compounds. We reviewed the role of activated platelets in neurovascular processes and nutritional compounds in platelet activation.

Pulmonary arterial hypertension (PAH) is a chronic and progressive disease characterized by vasoconstriction and structural remodelling of the pulmonary arteries. Increased vascular resistance and elevated pulmonary arterial pressures contribute to right ventricular hypertrophy and eventually lead to heart failure and premature death. Symptoms of PAH include serious exercise intolerance, reducing the quality of life of patients.  Nutrition is increasingly being recognized as an important factor contributing to quality of life during disease, especially when exercise intolerance is present. There is however limited knowledge on the role of nutrition in PAH and nutritional guidelines are scarce. In the meantime, PAH patients are actively seeking advice on such matters. In the clinic, assessment of nutritional status or micronutrient concentrations are currently not standard practice and nutritional intervention is not part of regular treatment, due to the lack of evidence-based recommendations for PAH patients.In this thesis, the role of nutrition in PAH pathophysiology and the potential of nutritional intervention in the treatment of PAH is being explored. The aim of this thesis is to gain more knowledge on the prevalence of micronutrient deficiencies of patients with PAH and to explore possible nutritional interventions to reduce fatigue and improve exercise tolerance and quality of life in PAH patients. These objectives are addressed by 1) literature research and hypothesis generation, 2) measurement of micronutrient status in PAH and CTEPH patients, 3) exploration of the relation between levels of micronutrients and clinical and patient-related outcomes and 4) a study on the effect of nutritional intervention on muscle function in a mouse model of PAH.Chapter 2 summarizes current insights in the pathophysiological mechanisms underlying PAH. It zooms in on the potential involvement of nutritional status and micronutrient deficiencies on PAH exercise intoleranc

Contains fulltext : 229884.pdf (publisher's version ) (Open Access), Fatigue is very common among colorectal cancer (CRC) patients. We examined the association between adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) lifestyle recommendations and fatigue among stage I-III CRC patients, and whether inflammation mediated this association. Data from two prospective cohort studies were used. Adherence to the WCRF/AICR recommendations was expressed as a score ranging from 0-7, and assessed shortly after diagnosis. Six months post-diagnosis, fatigue was assessed with the European Organization for Research and Treatment of Cancer quality of life questionnaire C30 (EORTC QLQ-C30), and in a subpopulation, the plasma levels of inflammation markers (IL6, IL8, TNFα, and hsCRP) were assessed. Multiple linear regression analyses were performed to investigate the association between adherence to the WCRF/AICR recommendations and fatigue. To test mediation by inflammation, the PROCESS analytic tool developed by Hayes was used. A higher WCRF/AICR adherence score was associated with less fatigue six months after diagnosis (n = 1417, β -2.22, 95%CI -3.65; -0.78). In the population of analysis for the mediation analyses (n = 551), the total association between lifestyle and fatigue was (β -2.17, 95% CI -4.60; 0.25). A statistically significant indirect association via inflammation was observed (β -0.97, 95% CI -1.92; -0.21), explaining 45% of the total association between lifestyle and fatigue (-0.97/-2.17 × 100). Thus, inflammation is probably one of the underlying mechanisms linking lifestyle to fatigue.

Exercise induces a range of physiological responses involving different organs, tissues and systems. The acute exercise response refers to the metabolic and mechanical effects directly following exercise, while the recovery after exercise concerns mechanisms to repair, refuel, replenish and return to homeostasis. Longer-term adaptations are important for growth and supercompensation. The role of nutrition or specific nutrients in these processes is substantial and demands further investigation. In this thesis, we investigated the exercise response during acute and repeated exercise and exercise training. In addition, a dietary intervention was conducted to investigate whether nutritional status, i.e. high vs low carbohydrate intake, modulated of the exercise induced stress and immune response.First, we assessed the impact of exercise on the variation in blood magnesium levels before exercise and during 6hours post-exercise recovery in well-trained cyclists and triathletes. We showed that both ionized (iMg) and total magnesium (tMg) decreased directly after exercise and returned to pre-exercise levels within 3.5hours after exercise. The decrease in blood magnesium levels after exercise and subsequent increase a few hours later likely reflects re-distribution to muscles and to blood respectively. We concluded that exercise affects magnesium levels and timing of blood sampling to analyse magnesium status is important.These observations in athletes highlighted the impact of an acute bout of exercise, but what would happen when older adults exercise for multiple days in a row remained unclear. Therefore, we examined changes in iMg and tMg levels during four consecutive days of prolonged walking exercise (~8hours) in a group of very old adults (>80 years). Blood samples were collected at baseline (1 or 2 days before the first walking day) and every walking day directly after finishing. Our results showed that iMg levels dropped directly after the first day of walking, whi

Persistent physical impairment is frequently encountered after critical illness. Recent data point towards mitochondrial dysfunction as an important determinant of this phenomenon. This narrative review provides a comprehensive overview of the present knowledge of mitochondrial function during and after critical illness and the role and potential therapeutic applications of specific micronutrients to restore mitochondrial function. Increased lactate levels and decreased mitochondrial ATP-production are common findings during critical illness and considered to be associated with decreased activity of muscle mitochondrial complexes in the electron transfer system. Adequate nutrient levels are essential for mitochondrial function as several specific micronutrients play crucial roles in energy metabolism and ATP-production. We have addressed the role of B vitamins, ascorbic acid, α-tocopherol, selenium, zinc, coenzyme Q10, caffeine, melatonin, carnitine, nitrate, lipoic acid and taurine in mitochondrial function. B vitamins and lipoic acid are essential in the tricarboxylic acid cycle, while selenium, α-tocopherol, Coenzyme Q10, caffeine, and melatonin are suggested to boost the electron transfer system function. Carnitine is essential for fatty acid beta-oxidation. Selenium is involved in mitochondrial biogenesis. Notwithstanding the documented importance of several nutritional components for optimal mitochondrial function, at present, there are no studies providing directions for optimal requirements during or after critical illness although deficiencies of these specific micronutrients involved in mitochondrial metabolism are common. Considering the interplay between these specific micronutrients, future research should pay more attention to their combined supply to provide guidance for use in clinical practise. Revision number: YCLNU-D-17-01092R2.

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Item does not contain fulltext, BACKGROUND: Hypomagnesemia has been associated with diabetes, cardiovascular disease, and other disorders. Drug use has been suggested as one of the risk factors for low magnesium (Mg) levels. In the elderly population, prone to polypharmacy and inadequate Mg intake, hypomagnesemia might be relevant. Therefore, we aimed to investigate associations between drug use and plasma Mg. METHODS: Cross-sectional data of 343 Dutch geriatric outpatients were analysed by Cox and linear regression, while adjusting for covariates. Drug groups were coded according to the Anatomical Therapeutic Chemical classification system; use was compared to non-use. Hypomagnesemia was defined as plasma Mg < 0.75 mmol/l and <0.70 mmol/l. RESULTS: Prevalence of hypomagnesemia was 22.2% (Mg < 0.75 mmol/l) or 12.2% (Mg < 0.70 mmol/l); 67.6% of the patients used >/=5 medications (polypharmacy). The number of different drugs used was inversely linearly associated with Mg level (beta -0.01; p < 0.01). Fully adjusted Cox regression showed significant associations of polypharmacy with hypomagnesemia (Mg < 0.75 mmol/l) (prevalence ratio (PR) 1.81; 95%CI 1.08-3.14), proton pump inhibitors (PR 1.80; 95%CI 1.20-2.72), and metformin (PR 2.34; 95%CI 1.56-3.50). Moreover, stratified analyses pointed towards associations with calcium supplements (PR 2.26; 95%CI 1.20-4.26), insulins (PR 3.88; 95%CI 2.19-6.86), vitamin K antagonists (PR 2.01; 95%CI 1.05-3.85), statins (PR 2.44; 95%CI 1.31-4.56), and bisphosphonates (PR 2.97; 95%CI 1.65-5.36) in patients <80 years; selective beta blockers (PR 2.01; 95%CI 1.19-3.40) if BMI <27.0 kg/m(2); and adrenergic inhalants in male users (PR 3.62; 95%CI 1.73-7.56). Linear regression supported these associations. CONCLUSION: As polypharmacy and several medications are associated with hypomagnesemia, Mg merits more attention, particularly in diabetes, cardiovascular disease, and in side-effects of proton pump inhibitors and calcium supplements.

This thesis describes the development of a G Protein-Coupled Receptor (GPCR) screening technology that combines a receptor cell array (~300 spots) with microfluidics. This technology was developed for the purpose of sensing the taste of, or active components in complex samples. GPCR activation was monitored using a genetically encoded calcium indicator (GECI) which was based on a change in Förster Resonance Energy Transfer (FRET) between two fluorescent proteins linked by a calcium binding domain which, upon binding of calcium, induces a conformational change between the fluorophores. The receptor cell arrays were created by reverse transfection of printed plasmid DNA. The arrays were assembled in a flowcell, connected to a microfluidic system, and mounted on a stereo fluorescence microscope. This setup allowed for controlled and importantly, repeated sample exposure while monitoring the changes in intracellular calcium in real-time. GPCRs play an important role in many physiological or disease-related processes. These membrane proteins have evolved to sense a wide range of molecules that can be of either exogenous or endogenous origin. Their sensing mechanisms are complex and potentially involve many cellular signalling events depending the cell type. The introductory chapter of this thesis presents a brief overview of the GPCR types and their signalling pathways with a focus on taste signalling. This chapter also places the microfluidic receptomics technology within the framework of existing receptor screening technologies. The second chapter explores the general principles, setup and characterization of the microfluidic biosensor to measure GPCR activation via imaging of [Ca2+] changes in recombinant human HEK293 cells. These cells expressed a combination of the Neurokinin 1-receptor and Cameleon YC3.6 protein as calcium indicator. Here, a stable cell line was employed for robust expression with little variation Next to GPCRs, the system was also used for the det

Cachexia is a common, serious and yet often under-recognised complication of cancer. Most obvious clinical manifestations of cachexia are loss of muscle mass, sometimes also including loss of fat mass and hence weight loss. This is driven by metabolic changes with or without a reduction in food intake, including elevated energy expenditure, excess catabolism and inflammation. Cachexia affects most patients with advanced stage cancer, with in some cancers more than 60% of all patients showing weight loss. Patients suffering from cachexia often also experience fatigue, muscle weakness and reduced response to cancer treatment. Conventional nutritional support is generally ineffective, the more so as anorexia often also develops in these patients. Together, these factors not only contribute to a reduced quality of life in these patients but are also assumed to be directly responsible for 20% of all cancer deaths. Thereby, aim of the current thesis was to get more insight into the processes driving this complex cachexia syndrome. Moreover, possible treatment targets and modalities were tested. In view of the variation in degree and clinical manifestations of cancer cachexia, variations in body composition and relative amounts of lean or fat mass are commonly occurring. To investigate possible consequences for the pharmacokinetics of cancer medication, associations between body composition and side-effects of chemotherapeutic treatment were studied in chapter 2. This was performed in a cohort of colon cancer patients receiving a treatment regimen consisting of capacetabine and oxaliplatin. Most patients [90%] experienced some side-effect during their treatment. Reductions in the dose of oxaliplatin were most common, while capecitabine treatment was usually not reduced. In contradiction to literature, we found that the amount of muscle mass, both absolute and relative to fat mass, was not associated with side-effects. However, we did find that the amount of fat infiltratio

Skeletal muscle responds to exercise by a diversity of processes that collectively contribute to short-term and structural adaptations to the demanded performance capacities. There is common consensus that, in general, adequate nutrient availability during and after exercise is important to maximise skeletal muscle adaptation and ultimately performance. At the same time, several knowledge gaps remain regarding the precise mechanisms underlying these effects on adaptation, the most optimal nutrient composition in relation to type of exercise, optimal timing etc. This dissertation addresses some of these unsolved issues by studying the role of carbohydrates and proteins during adaptation following different forms of exercise. The first part (chapters 2 – 4) focusses on carbohydrate availability with resistance exercise, whereas the second part (chapters 5 - 7) specifically addresses the effects and potential of protein supplementation with endurance training. In chapter 2 we reviewed the existing literature regarding the role of skeletal muscle glycogen with endurance and resistance exercise. Based on this review we concluded that the role of muscle glycogen levels and/or carbohydrate availability on the skeletal muscle adaptive response to resistance exercise requires further scientific attention. To experimentally explore this, we assessed the impact of a pre-exercise meal that differed in macronutrient content on skeletal muscle glycogen levels and acute transcriptional level analysing specific mRNAs in the post-resistance exercise period in chapter 3. Specifically, after a glycogen depleting endurance exercise session in the morning, subjects received an isocaloric mixed meal containing different amounts of carbohydrates and fat 2 hours before a resistance exercise session in the afternoon, while ample protein was provided throughout the day. We hypothesized that some of the selected mRNAs associated with substrate metabolism and mitochondrial biogenesis would dif

The genetically encoded calcium sensor protein Cameleon YC3.6 has previously been applied for functional G protein–coupled receptor screening using receptor cell arrays. However, different types of sensors are available, with a wide range in [Ca2+] sensitivity, Hill coefficients, calcium binding domains, and fluorophores, which could potentially improve the performance of the assay. Here, we compared the responses of 3 structurally different calcium sensor proteins (Cameleon YC3.6, Nano140, and Twitch2B) simultaneously, on a single chip, at different cytosolic expression levels and in combination with 2 different bitter receptors, TAS2R8 and TAS2R14. Sensor concentrations were modified by varying the amount of calcium sensor DNA that was printed on the DNA arrays prior to reverse transfection. We found that ~2-fold lower concentrations of calcium sensor protein, by transfecting 4 times less sensor-coding DNA, resulted in more sensitive bitter responses. The best results were obtained with Twitch2B, where, relative to YC3.6 at the default DNA concentration, a 4-fold lower DNA concentration increased sensitivity 60-fold and signal strength 5- to 10-fold. Next, we compared the performance of YC3.6 and Twitch2B against an array with 11 different bitter taste receptors. We observed a 2- to 8-fold increase in sensitivity using Twitch2B compared with YC3.6. The bitter receptor arrays contained 300 spots and could be exposed to a series of 18 injections within 1 h resulting in 5400 measurements. These optimized sensor conditions provide a basis for enhancing receptomics calcium assays for receptors with poor Ca2+ signaling and will benefit future high-throughput receptomics experiments.

Background: Pulmonary arterial hypertension (PAH) is a progressive and fatal disease predominantly affecting women and characterized by right ventricular (RV) remodeling. PAH patients experience exercise intolerance and fatigue, often associated with functional decline of their cardiac and skeletal muscle. As treatment options for these disease manifestations are very limited, there is a need for novel therapeutic strategies. The present study used a pulmonary arterial hypertension model in female mice to investigate effects of a nutritional combination (containing extra protein, leucine, fish oil and oligosaccharides) presumably targeting pathways involved in cardiac and skeletal muscle remodeling. Methods: Pulmonary arterial hypertension was induced in female mice (C57/BL6) by weekly administration of monocrotaline (MCT; s.c. 600 mg/kg) during 8 weeks, using saline injection as control. During that period, one MCT group (MCT; n=9) and the sham group (Sham; n=9) received a control diet (standard AIN-93M) while a further MCT-treated group received the nutritional intervention (NI, isocaloric) (MCT+NI; n=10). Histological analyses were performed on the RV, tibialis anterior (TA), soleus and extensor digitorum longus (EDL) muscle. Microarray and qRT-PCR analysis for gene expression were performed in RV tissue, and protein analysis by Western blot in tibialis anterior material. Results: Compared to sham mice, MCT mice showed an increase in heart weight by 7%, RV thickness by 13% and fibrosis by 60% (all p<0.05), which were attenuated in MCT+NI mice. Gene Set Enrichment Analysis (GSEA) of array data from the RV confirmed upregulation of fibrotic pathways in the MCT-compared to sham-treated mice (P<0.05), which were downregulated in MCT+NI mice. In addition, skeletal muscle fiber cross-sectional area (CSA) of the tibialis anterior was reduced (P<0.05) by 22% in MCT compared to sham mice, but preserved in the MCT+NI group (1503 vs. 1178 vs 1495 µm2, respectively), with pr

Previous studies have shown that exercise-induced changes in cytokine profiles depend on exercise duration and intensity. Studies are generally limited to a single day, and insight into the time course during multiple days of exercise is lacking. Therefore, this study assessed cytokine responses during multiple days of moderate intensity exercise in men and women. Fifty males (58.9 ± 9.9 years) and fifty females (50.9 ± 11.2 years) were monitored on 4 consecutive days at which they walked on average ~9 h/d at a self-determined pace. Blood samples were collected 1 or 2 days prior to the start of the exercise (baseline) and every walking day immediately post-exercise. Blood samples were analyzed for IL-6, IL-8, IL-10, IL-1β, and TNF-α concentrations. All cytokine concentrations increased from baseline to post-exercise at day 1 (P < .001). Thereafter, concentrations decreased from day 1 to day 2 (P < .01), remaining rather stable during the next days. IL-1β and TNF-α were higher in men at baseline and during all days. In conclusion, exercise-induced cytokine increases attenuated on subsequent days, although daily workload remained constant. Men and women showed different baseline levels but similar exercise responses. These results suggest that individuals adapt rapidly to this type of repeated exercise.

Contains fulltext : 196745.pdf (Publisher’s version ) (Open Access), PURPOSE: The aim of the present study was to assess the effect of prolonged and repeated exercise on iron metabolism in middle-aged adults and to compare differences between sexes. METHODS: 50 male (58.9 +/- 9.9 year) and 48 female (50.9 +/- 11.2 year) individuals were monitored on 4 consecutive days at which they walked on average 8 h and 44 min per day at a self-determined pace. Blood samples were collected 1 or 2 days prior to the start of the exercise (baseline) and every day immediately post-exercise. Samples were analysed for iron, ferritin, haemoglobin, and haptoglobin concentrations. RESULTS: Plasma iron decreased across days, while ferritin increased across days (both p < 0.001). Haptoglobin showed a decrease (p < 0.001) after the first day and increased over subsequent days (p < 0.001). Haemoglobin did not change after the first day, but increased during subsequent days (p < 0.05). At baseline, 8% of the participants had iron concentrations below minimum reference value (10 micromol/L), this increased to 43% at day 4. There was an interaction between sex and exercise days on iron (p = 0.028), ferritin (p < 0.001) and haemoglobin levels (p = 0.004), but not on haptoglobin levels. CONCLUSION: This study showed decreases in iron, increases in ferritin, a decrease followed by increases in haptoglobin and no change followed by increases in haemoglobin. This is most likely explained by (foot strike) haemolysis, inflammation, and sweat and urine losses. These processes resulted in iron levels below minimum reference value in a large number of our participants.

Purpose: The aim of the present study was to assess the effect of prolonged and repeated exercise on iron metabolism in middle-aged adults and to compare differences between sexes. Methods: 50 male (58.9 ± 9.9 year) and 48 female (50.9 ± 11.2 year) individuals were monitored on 4 consecutive days at which they walked on average 8 h and 44 min per day at a self-determined pace. Blood samples were collected 1 or 2 days prior to the start of the exercise (baseline) and every day immediately post-exercise. Samples were analysed for iron, ferritin, haemoglobin, and haptoglobin concentrations. Results: Plasma iron decreased across days, while ferritin increased across days (both p < 0.001). Haptoglobin showed a decrease (p < 0.001) after the first day and increased over subsequent days (p < 0.001). Haemoglobin did not change after the first day, but increased during subsequent days (p < 0.05). At baseline, 8% of the participants had iron concentrations below minimum reference value (10 µmol/L), this increased to 43% at day 4. There was an interaction between sex and exercise days on iron (p = 0.028), ferritin (p < 0.001) and haemoglobin levels (p = 0.004), but not on haptoglobin levels. Conclusion: This study showed decreases in iron, increases in ferritin, a decrease followed by increases in haptoglobin and no change followed by increases in haemoglobin. This is most likely explained by (foot strike) haemolysis, inflammation, and sweat and urine losses. These processes resulted in iron levels below minimum reference value in a large number of our participants.

Aims Chemotherapeutic treatment is regularly accompanied by side‐effects. Hydrophilic chemotherapeutics such as capecitabine and oxaliplatin (CAPOX), often used in colorectal cancer treatment, predominantly accumulate in non adipose tissues. Therefore the aim of this paper was to investigate whether body composition and fat infiltration inthe muscle (muscle attenuation and intermuscular‐adipose‐tissue [IMAT] content) are associated with chemotherapy induced toxicities. Methods In this retrospective observational study, we collected data from 115 colorectal cancer patients receiving adjuvant CAPOX chemotherapy between 2006 and 2015. Information on cancer characteristics were obtained from the Netherlands Cancer Registry. Diagnostic CT scans were retrieved to assess cross‐sectional areas of skeletal muscle and adipose tissue at the third lumbar vertebrae. Information on dose‐limiting toxicity [DLT] and relative administered dose (as % of BSA‐based‐planned‐dose) were retrieved from medical charts. Associations between body composition,muscle quality and chemotherapy‐induced toxicities were determined using Cox‐regression and linear‐regression analyses. Results We found that DLT incidence was 90% in our cohort: 50% had their dose reduced, 30% their next cyclepostponed, 4% a full treatment stop and 6% was hospitalized at their first DLT. Most common were reductions in oxaliplatin dose whilst keeping the capecitabine dose constant. Cox regression analysis indicated no association between body composition or muscle quality and DLT during the first treatment cycle or time to the first DLT. Multiple linear regression showed that higher IMAT‐index and IMAT muscle percentage were associated with a lower relative administered dose of oxaliplatin. Conclusions In conclusion; only IMAT, not skeletal or fat area was associated with dose‐limiting toxicities among these CRC patients who received CAPOX treatment.

1 juni 2017, Item does not contain fulltext, Magnesium is essential for optimal sport performance, generating an interest to monitor its status in athletes. However, before measuring magnesium status in blood could become routine, more insight into its diurnal fluctuations and effects of exercise itself is necessary. Therefore, we measured the effect of an acute bout of exercise on ionized (iMg) and total plasma magnesium (tMg) in blood obtained from 18 healthy well-trained endurance athletes (age, 31.1 +/- 8.1 yr.; VO2max, 50.9 +/- 7.5 ml/kg/min) at multiple time points, and compared this with a resting situation. At both days, 7 blood samples were taken at set time points (8:30 fasted, 11:00, 12:30, 13:30, 15:00, 16:00, 18:30). The control day was included to correct for a putative diurnal fluctuation of magnesium. During the exercise day, athletes performed a 90 min bicycle ergometer test (70% VO2max) between 11:00 and 12:30. Whole blood samples were analyzed for iMg and plasma for tMg concentrations. Both concentrations decreased significantly after exercise (0.52 +/- 0.04-0.45 +/- 0.03 mmol/L and 0.81 +/- 0.07-0.73 +/- 0.06 mmol/L, respectively, p < .001) while no significant decline was observed during that time-interval on control days. Both, iMg and tMg, returned to baseline, on average, 2.5 hr after exercise. These findings suggest that timing of blood sampling to analyze Mg status is important. Additional research is needed to establish the recovery time after different types of exercise to come to a general advice regarding the timing of magnesium status assessment in practice.

Background: Activation of the ileal brake by casein induces satiety signals and reduces energy intake. However, adverse effects of intraileal casein administration have not been studied before. These adverse effects may include impaired amino acid digestion, absorption and immune activation. Objective: To investigate the effects of intraileal infusion of native casein on plasma amino acid appearance, immune activation and gastrointestinal (GI) symptoms. Design: A randomized single-blind cross over study was performed in 13 healthy subjects (6 male; mean age 26 ± 2.9 years; mean body mass index 22.8 ± 0.4 kg/m-2), who were intubated with a naso-ileal feeding catheter. Thirty minutes after intake of a standardized breakfast, participants received an ileal infusion, containing either control (C) consisting of saline, a low-dose (17.2 kcal) casein (LP) or a high-dose (51.7 kcal) of casein (HP) over a period of 90 min. Blood samples were collected for analysis of amino acids (AAs), C-reactive protein (CRP), pro-inflammatory cytokines and oxylipins at regular intervals. Furthermore, GI symptom questionnaires were collected before, during and after ileal infusion. Results: None of the subjects reported any GI symptoms before, during or after ileal infusion of C, LP and HP. Plasma concentrations of all AAs analyzed were significantly increased after infusion of HP as compared to C (p <0.001), and most AAs were increased after infusion of LP (p <0.001). In total, 12.49 ± 1.73 and 3.18 ± 0.87 g AAs were found in plasma after intraileal infusion of HP and LP, corresponding to 93 ± 13% (HP) and 72 ± 20% (LP) of AAs infused as casein, respectively. Ileal casein infusion did not affect plasma concentrations of CRP, IL-6, IL-8, IL-1β and TNF-α. Infusion of HP resulted in a decreased concentration of 11,12-dihydroxyeicosatrienoic acid whereas none of the other oxylipins analyzed were affected. Conclusions: A single intraileal infusion of native casein results in a con

Background: Anorexia can occur as a serious complication of disease. Increasing evidence suggests that inflammation plays a major role, along with a hypothalamic dysregulation characterized by locally elevated serotonin levels. The present study was undertaken to further explore the connections between peripheral inflammation, anorexia and hypothalamic serotonin metabolism and signaling pathways. First, we investigated the response of two hypothalamic neuronal cell lines to TNFα, IL-6 and LPS. Next, we studied transcriptomic changes and serotonergic activity in the hypothalamus of mice after intraperitoneal injection with TNFα, IL-6 or a combination of TNFα and IL-6. Results: In vitro, we showed that hypothalamic neurons responded to inflammatory mediators by releasing cytokines. This inflammatory response was associated with an increased serotonin release. Mice injected with TNFα and IL-6 showed decreased food intake, associated with altered expression of inflammation-related genes in the hypothalamus. In addition, hypothalamic serotonin turnover showed to be elevated in treated mice. Conclusions: Overall, our results underline that peripheral inflammation reaches the hypothalamus where it affects hypothalamic serotoninergic metabolism. These hypothalamic changes in serotonin pathways are associated with decreased food intake, providing evidence for a role of serotonin in inflammation-induced anorexia.

Conjugates of fatty acids and amines, including endocannabinoids, are known to play important roles as endogenous signalling molecules. Among these, the ethanolamine conjugate of the n-3 poly unsaturated long chain fatty acid (PUFA) docosahexaenoic acid (22:6n-3) (DHA) was shown to possess strong anti-inflammatory properties. Previously, we identified the serotonin conjugate of DHA, docosahexaenoyl serotonin (DHA-5-HT), in intestinal tissues and showed that its levels are markedly influenced by intake of n-3 PUFAs. However, its biological roles remain to be elucidated. Here, we show that DHA-5-HT possesses potent anti-inflammatory properties by attenuating the IL-23-IL-17 signalling cascade in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Transcriptome analysis revealed that DHA-5-HT down-regulates LPS-induced genes, particularly those involved in generating a CD4 + Th17 response. Hence, levels of PGE2, IL-6, IL-1β, and IL-23, all pivotal macrophage-produced mediators driving the activation of pathogenic Th17 cells in a concerted way, were found to be significantly suppressed by concentrations as low as 100–500 nM DHA-5-HT. Furthermore, DHA-5-HT inhibited the ability of RAW264.7 cells to migrate and downregulated chemokines like MCP-1, CCL-20, and gene-expression of CCL-22 and of several metalloproteinases. Gene set enrichment analysis (GSEA) suggested negative overlap with gene sets linked to inflammatory bowel disease (IBD) and positive overlap with gene sets related to the Nrf2 pathway. The specific formation of DHA-5-HT in the gut, combined with increasing data underlining the importance of the IL-23-IL-17 signalling pathway in the aetiology of many chronic inflammatory diseases merits further investigation into its potential as therapeutic compound in e.g. IBD or intestinal tumorigenesis.

Purpose: Adverse drug reactions as well as vitamin D deficiency are issues of public health concern in older people. However, relatively little is known about the impact of drug use on vitamin D status. Our primary aim is to explore associations between drug use and vitamin D status in older people. Furthermore, prevalences of drug use and vitamin D deficiency are estimated. Methods: In a population of 873 community-dwelling Dutch geriatric outpatients, we explored the cross-sectional relationships of polypharmacy (≥5 medications concomitantly used), severe polypharmacy (≥10 medications), and use of twenty-one specific drug groups, with serum 25-hydroxyvitamin D (25(OH)D) by analysis of covariance. Results: Overall prevalence of polypharmacy was 65 %, of severe polypharmacy 22 %. Depending on the cut-off value, prevalence of vitamin D deficiency was 49 % (