Low glycaemic diets alter lipid metabolism to influence tumour growth.

Dietary interventions can change metabolite levels in the tumour microenvironment, which might then affect cancer cell metabolism to alter tumour growth1-5. Although caloric restriction (CR) and a ketogenic diet (KD) are often thought to limit tumour progression by lowering blood glucose and insulin levels6-8, we found that only CR inhibits the growth of select tumour allografts in mice, suggesting that other mechanisms contribute to tumour growth inhibition. A change in nutrient availability observed with CR, but not with KD, is lower lipid levels in the plasma and tumours. Upregulation of stearoyl-CoA desaturase (SCD), which synthesises monounsaturated fatty acids, is required for cancer cells to proliferate in a lipid-depleted environment, and CR also impairs tumour SCD activity to cause an imbalance between unsaturated and saturated fatty acids to slow tumour growth. Enforcing cancer cell SCD expression or raising circulating lipid levels through a higher-fat CR diet confers resistance to the effects of CR. By contrast, although KD also impairs tumour SCD activity, KD-driven increases in lipid availability maintain the unsaturated to saturated fatty acid ratios in tumours, and changing the KD fat composition to increase tumour saturated fatty acid levels cooperates with decreased tumour SCD activity to slow tumour growth. These data suggest that diet-induced mismatches between tumour fatty acid desaturation activity and the availability of specific fatty acid species determine whether low glycaemic diets impair tumour growth.

Concentrations of fat-soluble nutrients and blood inflammatory compounds in mother-infant dyads at birth.

BACKGROUND: Perinatal inflammation adversely affects health. Therefore, aims of this IRB-approved study are: (1) compare inflammatory compounds within and between maternal and umbilical cord blood samples at the time of delivery, (2) assess relationships between inflammatory compounds in maternal and cord blood with birth characteristics/outcomes, and (3) assess relationships between blood and placental fat-soluble nutrients with blood levels of individual inflammatory compounds. METHODS: Mother-infant dyads were enrolled (n = 152) for collection of birth data and biological samples of maternal blood, umbilical cord blood, and placental tissue. Nutrient levels included: lutein + zeaxanthin; lycopene; α-, ß-carotene; ß-cryptoxanthin; retinol; α-, γ-, δ-tocopherol. Inflammatory compounds included: tumor necrosis factor-α, superoxide dismutase, interleukins (IL) 1ß, 2, 6, 8, 10. RESULTS: Median inflammatory compound levels were 1.2-2.3 times higher in cord vs. maternal blood, except IL2 (1.3 times lower). Multiple significant correlations existed between maternal vs. infant inflammatory compounds (range of r = 0.22-0.48). While relationships existed with blood nutrient levels, the most significant were identified in placenta where all nutrients (except δ-tocopherol) exhibited relationships with inflammatory compounds. Relationships between anti-inflammatory nutrients and proinflammatory compounds were primarily inverse. CONCLUSION: Inflammation is strongly correlated between mother-infant dyads. Fat-soluble nutrients have relationships with inflammatory compounds, suggesting nutrition is a modifiable factor. IMPACT: Mother and newborn inflammation status are strongly interrelated. Levels of fat-soluble nutrients in blood, but especially placenta, are associated with blood levels of proinflammatory and anti-inflammatory compounds in both mother and newborn infant. As fat-soluble nutrient levels are associated with blood inflammatory compounds, nutrition is a modifiable factor to modulate inflammation and improve perinatal outcomes.

Metabolites, Nutrients, and Lifestyle Factors in Relation to Coffee Consumption: An Environment-Wide Association Study.

Coffee consumption has been inversely associated with various diseases; however, the underlying mechanisms are not entirely clear. We used data of 17,752 Third National Health and Nutrition Examination Survey participants to investigate the association of 245 metabolites, nutrients, and lifestyle factors with coffee consumption. We used data from the first phase (n = 8825) to identify factors with a false discovery rate of <5%. We then replicated our results using data from the second phase (n = 8927). Regular coffee consumption was positively associated with active and passive smoking, serum lead and urinary cadmium concentrations, dietary intake of potassium and magnesium, and aspirin intake. In contrast, regular coffee consumption was inversely associated with serum folate and red blood cell folate levels, serum vitamin E and C, and beta-cryptoxanthin concentrations, Healthy Eating Index score, and total serum bilirubin. Most of the aforementioned associations were also observed for caffeinated beverage intake. In our assessment of the association between coffee consumption and selected metabolites, nutrients, and lifestyle factors, we observed that regular coffee and caffeinated beverage consumption was strongly associated with smoking, serum lead levels, and poorer dietary habits.

Effect of surgical or immune castration on postprandial nutrient profiles in male pigs.

To avoid boar taint before slaughtering, late castration by immunisation against gonadotrophin releasing hormone or immunocastration has been developed. The current study aimed at determining whether differences in feed efficiency between castrated male (CM), immune castrated (IM) and entire male pigs (EM) can be explained by differences in nutrient plasma profiles after a meal. In this study, 24 male pigs (n = 8/type) were enrolled between 14 to 19 weeks of age. Entire and IM pigs ate less and were more feed efficient than CM pigs (p < 0.05). The postprandial plasma profiles of glucose, insulin, urea and amino acids (AA) were determined before (d -6), just after (d 8) and well after (d 16) the decrease in testicular hormones in IM pigs. For each test day, pigs were fasted overnight and subsequently fed a small meal (400 g). On d -6, postprandial profiles of plasma glucose of IM pigs did not differ from the two other types of pigs. On d 8, EM pigs had a greater average plasma glucose concentration than IM and CM pigs (p < 0.05) but the profiles did not differ. On d 16, the differences between profiles of glucose suggest a lower clearance of glucose in EM compared with IM and CM pigs. Plasma insulin did not significantly differ between the three types. Plasma urea profiles did not differ between CM, EM and IC pigs on d -6 whereas CM pigs showed higher plasma urea concentrations than EM and IM thereafter (p < 0.01). Among AA, Lys plasma concentrations were greater in CM than in EM and IM pigs on d -6, d 8 and d 16 (p < 0.05), whereas on d 16 plasma Hypro concentrations were lower in CM than in EM and IM pigs (p < 0.05). The finding that plasma glucose profiles were modified by immunocastration much faster and earlier than urea and AA profiles, suggest that the decrease in testicular hormones impacted energy metabolism more rapidly than protein metabolism.

Insulin-like growth factor I, binding proteins -1 and -3, risk of type 2 diabetes and macronutrient intakes in men.

The insulin-like growth factor (IGF) axis may be involved in the development of type 2 diabetes. We examined the associations of IGF-I and IGF binding proteins (IGFBP)-1 and -3 with diabetes risk and evaluated macronutrient intakes related to the observed associations. In a nested case-control study of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study of Finnish male smokers aged 50-69 years, the IGF variables were measured from baseline serum samples for a random sample of 310 men with diabetes diagnosed during a 12-year follow-up and for 310 controls matched by age, recruitment day and intervention group. Diet at baseline was assessed using a validated FFQ. The associations of IGF proteins with diabetes risk were estimated using conditional logistic regression and the associations with macronutrient intakes using linear regression. IGF-I and IGFBP-3 were not associated with the incidence of diabetes. Higher IGFBP-1 was associated with lower diabetes risk in an unadjusted crude model (OR 0·25; 95 % CI 0·15, 0·42 in the highest quartile compared with the lowest), but not after adjustment for BMI (corresponding OR 0·76; 95 % CI 0·41, 1·40). Intakes of carbohydrates, plant protein and milk protein associated positively and intake of meat protein and fat negatively with IGFBP-1 (P<0·005). IGFBP-1 was inversely associated with diabetes risk, but the association was substantially dependent on BMI. The associations between macronutrient intakes and IGFBP-1 may reflect influences of nutrients or foods on insulin concentrations.

Association between methylation potential and nutrient metabolism throughout the reproductive cycle of sows.

DNA methylation is an important epigenetic strategy for embryo development and survival. The one-carbon metabolism can be disturbed by inadequate provision of dietary methyl donors. Because of the continuous selection for larger litters, it is relevant to explore if highly prolific sows might encounter periods of methyl donor deficiency throughout their reproductive cycles. This study, therefore, assesses the fluctuation(s) in methylation potential (MP) and aims to link possible methyl donor deficiencies to nutrient metabolism. In total, 15 hybrid sows were followed from weaning of the previous reproductive cycle (d-5) to weaning of the present cycle. Blood samples were taken at d-5, 0, 21, 42, 63, 84 and d108 of gestation, the day of parturition (d115), two weeks of lactation (d129) and at weaning (d143). Blood plasma samples were analysed for S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), free methionine, free glycine, acetylcarnitine and 3-hydroxybutyrylcarnitine. Serum samples were analysed for urea and creatinine. Generally, MP (i.e. ratio SAM:SAH) increased throughout gestation (p = 0.009), but strongly fluctuated in the period around parturition and weaning. From d108 to parturition, absolute plasma levels of SAM (p < 0.001), SAH (p = 0.031) and methionine (p = 0.001) increased. The first two weeks of lactation were characterised by an increase in MP (p = 0.039) due to a remaining high value of SAM and a distinct decrease in SAH (p = 0.008). During the last two weeks of lactation, MP decreased (p = 0.038) due to a decrease in SAM (p < 0.001) and a stable value for SAH. The methylation reactions seem to continue after weaning, a period crucial for the follicular and embryonic development of the subsequent litter. This study thus demonstrates that the methylation status fluctuates substantially throughout a sow's reproductive cycle, and further research is needed to identify the factors affecting methylation status.

Nutrient pattern analysis in critically ill patients using Omics technology (NAChO) - Study protocol for a prospective observational study.

INTRODUCTION: Intensive care unit-acquired weakness (ICU-AW) is often observed in critically ill patients with prolonged intensive care unit (ICU) stay. We hypothesized that evolving metabolic abnormalities during prolonged ICU stay are reflected by changing nutrient patterns in blood, urine and skeletal muscle, and that these patterns differ in patients with/without ICU-AW and between patients with/without sepsis. METHODS: In a prospective single-center observational trial, we aim to recruit 100 critically ill patients (ICU length of stay ≥ 5 days) with severe sepsis/septic shock ("sepsis group", n = 50) or severe head trauma/intracerebral hemorrhage ("CNS group", n = 50). Patients will be sub-grouped for presence or absence of ICU-AW as determined by the Medical Research Council sum score. Blood and urine samples will be collected and subjected to comprehensive nutrient analysis at different time points by targeted quantitative mass spectrometric methods. In addition, changes in muscular tissue (biopsy, when available), muscular architecture (ultrasound), electrophysiology, body composition analyses (bioimpedance, cerebral magnetic resonance imaging), along with clinical status will be assessed. Patients will be followed-up for 180 and 360 days including assessment of quality of life. DISCUSSION: Key objective of this trial is to assess changes in nutrient pattern in blood and urine over time in critically ill patients with/without ICU-AW by using quantitative nutrient analysis techniques. Peer-reviewed published NAChO data will allow for a better understanding of metabolic changes in critically ill patients on standard liquid enteral nutrition and will likely open up new avenues for future therapeutic and nutritional interventions.