Plasma and urinary inositol isomer profiles measured by UHPLC-MS/MS reveal differences in scyllo-inositol levels between non-pregnant and pregnant women.

Previous studies support that myo- and D-chiro-inositol isomers are promising bioactives for the treatment of women with polycystic ovary syndrome and for lowering the risk of gestational diabetes mellitus in pregnant women, whereas scyllo-inositol may have some benefits for neurological disorders (e.g., Alzheimer's disease). Though potentially useful to better understand inositol isomer metabolism and study their role in health and disease, routine analysis of inositol isomers in plasma and urine with a single analytical method is not yet feasible due to the lack of a suitable analytical assay. To address this, we developed and validated a robust ultra-high-performance-liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method for the quantification of inositol isomers in plasma and urine. This method resolves seven inositol isomers with accurate quantification of total chiro- (D and L enantiomers), myo-, and scyllo-inositols and is semi-quantitative for neo-inositol. For urine and plasma myo-inositol, the method repeatability and intermediate reproducibility were below 6% and 8%, respectively. Then, for both chiro- and scyllo-inositols, repeatability and intermediate reproducibility were below 10% and 14%, respectively. A pilot study was carried out to quantify and compare the pattern of inositol isomers in urine and plasma of non-pregnant and pregnant women and showed for the first time that urinary myo- and scyllo-inositol concentrations were significantly higher for women in the third trimester of pregnancy compared with non-pregnant women. These findings warrant further research to understand the biological significance of the observed differences in inositol profiles and suggest a potential role of scyllo-inositol.Graphical abstract Plasma and urinary inositol isomer profiles measured by UHPLC-MS/MS reveal differences in scyllo-inositol levels between non-pregnant and pregnant women.

Effects of protein quantity and type on diet induced thermogenesis in overweight adults: A randomized controlled trial.

BACKGROUND & AIMS: Protein content of a meal is hypothesized to drive DIT dose-dependently. However, no single meal study exists comparing two different doses of protein on DIT. In addition, the source of protein, particularly whey protein, was shown to have a higher DIT than casein and soy in the acute setting, however the mechanism behind this difference is not yet clear. The aim of the present work is therefore to evaluate the efficacy of two different doses and types of protein (whey protein and casein) on DIT in overweight adults. METHODS: Randomized, double blind crossover including seventeen overweight men and women assigned to four isocaloric study treatments where protein and carbohydrate were exchanged: control, 30 g of whey protein microgels (WPM30), 50 g WPM (WPM50) or 50 g micellar casein (MC50). Energy expenditure was measured by indirect calorimetry. Blood, breath and urine samples were collected in order to measure substrate oxidation, amino acid profile, glucose and insulin, protein turnover and other metabolic parameters. RESULTS: DIT was 6.7 ± 3.7%, 13.0 ± 5.0%, 18.0 ± 5.0% and 16.0 ± 5.0% for control, WPM30, WPM50 and MC50, respectively. There was a significant difference between WPM50 and WPM30 (p < 0.005) and a trend was observed between WPM50 and MC50 (p = 0.06). WPM50 resulted in the highest total, essential, and branched-chain plasma amino acid concentrations when compared with the other study treatments (p < 0.005) and a higher insulin concentration than MC50 (p < 0.005). Protein oxidation was higher for WPM50 than MC50. Protein turnover was significantly correlated with DIT through total leucine oxidation (r = 0.52, p = 0.005). CONCLUSIONS: Our findings show that DIT does increase at a dose beyond 30 g of WPM and that the type of dairy protein may have an effect on DIT with WPM tending towards a higher DIT than casein. Although further research is required to understand the mechanism behind the effect of different protein sources on thermogenesis, we suggest that amongst the components of protein turnover, protein oxidation may be an important driver of thermogenesis at doses higher than 30 g. These results have concrete implications when choosing a dose of protein to optimize its thermogenic effect. CLINICAL TRIAL REGISTRY NUMBER: NCT02303080 www.clinicaltrials.gov.

A 48-Hour Vegan Diet Challenge in Healthy Women and Men Induces a BRANCH-Chain Amino Acid Related, Health Associated, Metabolic Signature.

SCOPE: Research is limited on diet challenges to improve health. A short-term, vegan protein diet regimen nutritionally balanced in macronutrient composition compared to an omnivorous diet is hypothesized to improve metabolic measurements of blood sugar regulation, blood lipids, and amino acid metabolism. METHODS AND RESULTS: This randomized, cross-over, controlled vegan versus animal diet challenge is conducted on 21 (11 female,10 male) healthy participants. Fasting plasma is measured during a 3 d diet intervention for clinical biochemistry and metabonomics. Intervention diet plans meet individual caloric needs. Meals are provided and supervised. Diet compliance is monitored. CONCLUSIONS: The vegan diet lowers triglycerides, insulin and homeostatic model assessment (HOMA-IR), bile acids, elevated magnesium levels, and changed branched-chain amino acids (BCAAs) metabolism (p < 0.05), potentiating insulin and blood sugar control after 48 h. Cholesterol control improves significantly in the vegan versus omnivorous diets. Plasma amino acid and magnesium concentrations positively correlate with dietary amino acids. Polyunsaturated fatty acids and dietary fiber inversely correlate with insulin, HOMA-IR, and triglycerides. Nutritional biochemistries, BCAAs, insulin, and HOMA-IR are impacted by sexual dimorphism. A health-promoting, BCAA-associated metabolic signature is produced from a short-term, healthy, controlled, vegan diet challenge when compared with a healthy, controlled, omnivorous diet.

Protein choices targeting thermogenesis and metabolism.

BACKGROUND: Dietary proteins stimulate thermogenesis and satiety more than does carbohydrate or fat; however, less is known about the differences between protein sources. OBJECTIVE: The objective was to determine the differential effects of 3 proteins on energy metabolism, satiety, and glucose control. DESIGN: Energy metabolism, satiety, and glucose control were measured in 23 lean, healthy subjects on separate occasions, before and 5.5 h after consumption of 4 isocaloric test meals in a randomized, double-blind, crossover design. Three meals consisting of 50% protein (whey, casein, or soy), 40% carbohydrate, and 10% fat and a fourth meal consisting of 95.5% carbohydrate were compared with a glucose meal that provided the same glucose load as the protein meals. RESULTS: The thermic effect was greater after the whey (14.4 ± 0.5%) than after the casein (12.0 ± 0.6%; P = 0.002) and soy (11.6 ± 0.5%; P = 0.0001) meals and was greater after the whey, casein, and soy meals than after the high-carbohydrate meal (6.6 ± 0.5%; P < 0.0001). Cumulative fat oxidation tended to be greater after the whey meal (16.2 ± 1.1 g) than after the soy meal (13.7 ± 1.0 g; P = 0.097) and was greater after the whey and soy meals than after the high-carbohydrate meal (10.9 ± 0.9 g; P < 0.05). The glycemic response to glucose was attenuated 32% by the proteins (P < 0.001) at the expense of a greater insulin response after whey than after glucose (154%; P = 0.02), casein (143%; P = 0.07), and soy (151%; P = 0.03). Subjective appetite sensations indicated that casein and soy were more satiating than whey (P < 0.01), but whey was more "liked" compared with casein and soy (P = 0.025 and P = 0.09, respectively). CONCLUSION: The results suggest that different protein sources could be used to modulate metabolism and subsequently energy balance.

Rosemary (Rosmarinus officinalis L.) leaf extract limits weight gain and liver steatosis in mice fed a high-fat diet.

The objective of this study was to investigate the effects of rosemary (Rosmarinus officinalis L.) leaf extract (RE) on the prevention of weight gain and associated metabolic disorders in mice fed a high-fat diet. For this purpose, RE was administered for 50 days at 20 or 200 mg/kg body weight (BW) to mice fed a high-fat diet. Body weight was monitored during the study and body composition was measured before and at the end of the intervention. Glucose tolerance, assessed by an intraperitoneal glucose tolerance test (IPGTT), and hepatic and faecal lipid contents were determined at the end of the study. Treatment with 200 mg/kg BW of RE induced a significant reduction of weight and fat mass gain (-64% and -57%, respectively) associated with an increase of faecal lipid excretion. This effect appears to be related to the inhibition of pancreatic lipase activity induced by RE, as demonstrated IN VITRO. While glucose tolerance and fasting glycaemia were not affected by RE treatment, hepatic triglyceride levels were decreased by 39% in RE-treated mice. Administration of the lower dose of RE (20 mg/kg BW) was ineffective on all the parameters measured. In conclusion, our results demonstrate that consumption of 200 mg/kg BW of RE can limit weight gain induced by a high-fat diet and protect against obesity-related liver steatosis.

Interleukin-18 protein level is upregulated in adipose tissue of obese mice.

In this study, we investigated the regulation of Interleukin-18 (IL-18) and caspase-1 mRNA and protein levels in adipose and liver tissue of obese (ob/ob) mice compared with ob/+ mice. In ob/ob mice, which have a twofold higher IL-18 plasma level as compared with lean mice, IL-18 mRNA expression was significantly reduced by 1.6-fold in adipose tissue, whereas protein level was enhanced fourfold as compared with ob/+ mice. However, caspase-1 mRNA expression and activity were significantly enhanced in adipose tissue of ob/ob mice. Conversely, both IL-18 mRNA and protein levels were slightly enhanced, but caspase-1 activity was reduced in liver of ob/ob mice as compared with lean mice. In conclusion, we show that adipose and hepatic IL-18 protein expressions are increased in obese mice. However, in contrast to liver, the adipose IL-18 protein level appears to be upregulated through a post-transcriptional mechanism probably involving caspase-1.

Neonatal dietary supplementation of arachidonic acid increases prostaglandin levels in adipose tissue but does not promote fat mass development in guinea pigs.

The role of arachidonic acid (AA) on the development of adipose tissue is still controversial since its metabolites, i.e., prostaglandins, can either stimulate or inhibit preadipocyte differentiation in vitro. In the present study, we evaluated the effects of early postnatal supplementation of AA on body weight and adipose tissue development in guinea pigs. Male newborn guinea pigs were fed for 21 days (day 21) with diets (milk and pellet) supplemented (+AA) or not (-AA) with 1.2% (total fatty acids) AA. From day 21 to day 105 both groups were fed a chow diet. The 21-days-old +AA pups showed a twofold higher AA accretion in phospholipids associated with a two- to sixfold increase in several prostaglandins, such as 6-keto PGF(1alpha) (the stable hydrolysis product of PGI(2)), PGF(2alpha), PGE(2), and PGD(2) in adipose tissue, compared with the -AA group. No difference in fat pad and body weight, aP2, and leptin gene expression in adipose tissue, fasting plasma glucose, free-fatty acids, and triglyceride concentration was observed between groups at day 21 or day 105. These results show that dietary supplementation of AA during the suckling/weaning period increases prostaglandin levels in adipose tissue but does not influence early fat mass development in the guinea pig.

Similar cholesterol-lowering properties of rice bran oil, with varied gamma-oryzanol, in mildly hypercholesterolemic men.

BACKGROUND: The cholesterol lowering properties of rice bran oil (RBO) containing differing amounts of non-saponifiable components have not been studied in humans, to our knowledge. AIM OF THE STUDY: To evaluate cholesterol lowering effects of RBO, with low and high amounts of gamma-oryzanol (ferulated plant sterols) in mildly hypercholesterolemic men. METHODS: Mildly hypercholesterolemic men, 38-64 y, starting cholesterol 4.9-8.4 mmol/l (n = 30), consumed 50 g/d peanut oil (PNO) in vehicles for 2 wks during a run-in period, then, without wash-out, were randomly equilibrated (based on initial level of cholesterol) into two groups to consume 50 g/d RBO low (0.05 g/d) or high (0.8 g/d) gamma-oryzanol for 4 wks, in a randomized, controlled, parallel design study. Subjects were free-living and consumed habitual diets with some restrictions. Plasma concentrations of total, LDL-,HDL-cholesterol and triacylglycerol were measured at base line and after 2, 4, and 6 wks. RESULTS: The two RBO types were not significantly different with respect to effects on various cholesterol parameters, at 2 and 4 wks, including total cholesterol, LDL-, HDL- and LDL/HDL cholesterol ratio. Low and high gamma-oryzanolcontaining RBO feeding for 4 wks lowered total plasma cholesterol (6.3 %), LDL-C (10.5 %) and the LDL-C/HDL-C ratio (18.9 %). CONCLUSIONS: RBO supplementation at ca. 50% total fat intake improved lipoprotein pattern in mildly hypercholesterolemic men. Methylated sterols in gamma-oryzanol are thought to be largely ineffective at inhibiting dietary cholesterol absorption, but could enhance cholesterol-lowering ability of 4-desmethylsterols. Assuming all ferulated sterols become de-ferulated in the gut, low and high gamma-oryzanolcontaining RBOs provided intestinal loads of 453 and 740 mg/d free 4-desmethylsterols, respectively. This intestinal load of 453-740 mg/d of efficacious free plant sterol equivalents had identical effects on lipoproteins.

Non-esterified plant sterols solubilized in low fat milks inhibit cholesterol absorption--a stable isotope double-blind crossover study.

BACKGROUND: The cholesterol absorption inhibiting properties of plant sterols in milks are unknown. The milk fat globule membrane components may enhance the absorption of cholesterol and could make plant sterols less efficient in this complex matrix. AIM OF THE STUDY: To evaluate in hypercholesterolemic men the cholesterol absorption inhibiting properties of verified properly solubilized, non-esterified plant sterols in partly vegetable oil containing milks. METHODS: The plant sterols in milk were determined to be properly solubilized, and to have effective in vitro functionality. Sixteen hypercholesterolemic adult men (initial total cholesterol 5.8-8.6 mM) then consumed milk containing sterols (1.8 g of non-esterified pure plant sterols/d) and control milk, alternatively, during two 6-day periods in a double blind cross over design. During the trial, cholesterol absorption was evaluated from the ratio of plasma isotopic enrichment of [26, 26, 26, 27, 27, 27-(2)H(6)]cholesterol from oral intake (35.6 +/- 0.2 micromol, +/- SEM) over enrichment of [23, 24, 25, 26, 27-(13)C(5)]cholesterol from intravenous injection (77.9 +/- 0.5 micromol). RESULTS: Plant sterols in low fat milks contained very few crystals > 11 microm in the presence and absence of bile salts and lysophospholipids, and inhibited cholesterol uptake in Caco-2 cell. This assured that the sterols were properly solubilized prior to the clinical trial. In the clinical study, compliance of volunteers was excellent. After tracer injections (72 h), the plasma [(2)H] and [(13)C] isotopic enrichments changed from 0.024 +/- 0.001 and 0.072 +/- 0.003 MPE (control) to 0.015 +/- 0.001 and 0.074 +/- 0.002 MPE during sterol treatment, respectively. Cholesterol absorption was reduced from 70.1 +/- 4.2 % with control to 41.1 +/- 4.0 % with milks containing plant sterol (P < 0.001). CONCLUSIONS: These results demonstrate that properly solubilized non-esterified plant sterols in milks significantly inhibit cholesterol absorption in mildly hypercholesterolemic men.

Cholesterol-lowering properties of amaranth grain and oil in hamsters.

Amaranth was an important ancient grain and has current nutritional potential, being high in protein, fiber, lysine, magnesium, calcium, and squalene. Limited, inconsistent evidence demonstrates amaranth grain or oil can lower cholesterol in animal models. In the present study, hamsters received hypercholesterolemic diets consisting of a control, 10 or 20% Amaranthus cruentus grain, or 2.5 or 5% crude amaranth oil for four weeks. Amaranth oil (5%) decreased total and non-high-density lipoprotein (HDL) cholesterol by 15 and 22%, respectively, compared to control. Amaranth grain (20%; providing 1.4% amaranth oil) lowered non-HDL cholesterol and raised HDL cholesterol. Amaranth grain and oil decreased very low-density lipoprotein (VLDL) cholesterol by 21-50%; and increased fecal excretion of particular neutral sterols and the bile acid ursodeoxycholate. Amaranth oil (5%) additionally increased the cholesterol synthesis rate, possibly due to compensatory mechanisms; and decreased hepatic cholesterol ester, indicating reduced cholesterol ester availability for VLDL secretion and consistency with reduced VLDL cholesterol. Amaranth thus affected absorption of cholesterol and bile acids, cholesterol lipoprotein distribution, hepatic cholesterol content, and cholesterol biosynthesis. Amaranth grain and oil did not affect these pathways identically.

Epidermal anti-Inflammatory properties of 5,11,14 20:3: effects on mouse ear edema, PGE2 levels in cultured keratinocytes, and PPAR activation.

BACKGROUND: 5,11,14 20:3 is similar to 20:4n-6 but lacks the internal Delta8 double bond essential for prostaglandin and eicosanoid synthesis. When previously fed to laboratory animals as a gymnosperm seed oil component it has shown anti-inflammatory properties. RESULTS: Herein, topically applied Podocarpus nagi methyl esters (containing 26% 5,11,14 20:3) were incorporated into mouse ear phospholipids, reduced 20:4n-6, and reduced 20:4n-6- and TPA-induced mouse ear edema. Purified 5,11,14 20:3 was taken up by cultured human skin keratinocytes, reduced 20:4n-6, and reduced PGE2 levels dramatically. Purified 5,11,14 20:3 did not affect PPARalpha, PPARgamma, or PPARdelta transactivation. CONCLUSIONS: Topical application of 5,11,14 20:3 to skin surfaces can thus reduce inflammatory processes, most likely by displacing 20:4n-6 from phospholipid pools and reducing downstream inflammatory products derived from 20:4n-6 such as PGE2 and leukotrienes. It could have potential use in treating clinical skin disorders resulting from overproduction of 20:4n-6-derived eicosanoid products.