Rapid and miniaturized qualitative and quantitative gas chromatography profiling of human blood total fatty acids.

The qualitative and quantitative profiling of fatty acids in human blood is a useful tool in disease prevention and health care, two concepts that are intimately related. In fact, fatty acid (FA) analysis can provide in-depth information on a specific metabolic state of individuals. The goal of the present research consisted of the development of a rapid and miniaturized analytical strategy for the complete characterization of the fatty acid profile in human blood. Sample collection was carried out by using the dried blood spot approach, while fatty acid derivatization to methyl esters was performed directly by using sodium methoxide and boron trifluoride. The following figures of merit were defined: intra- and inter-day repeatability, linearity range, limits of detection, and quantification. Additionally, the accuracy of the developed method was evaluated in the analysis of a certified reference human plasma sample. Apart from blood, the analytical procedure was also applied to samples of human serum and plasma. During the final stage of the research, the developed analytical method was performed in a fully automated manner. Graphical abstract.

Comprehensive two-dimensional liquid chromatography for polyphenol analysis in foodstuffs.

Polyphenols are a class of plant secondary metabolites that are recently drawing a special interest because of their broad spectrum of pharmacological effects. As they are characterized by an enormous structural variability, the identification of these molecules in food samples is a difficult task, and sometimes having only a limited number of commercially available reference materials is not of great help. One-dimensional liquid chromatography is the most widely applied analytical approach for their analysis. In particular, the hyphenation of liquid chromatography to mass spectrometry has come to play an influential role by allowing relatively fast tentative identification and accurate quantification of polyphenolic compounds at trace levels in vegetable media. However, when dealing with very complex real-world food samples, a single separation system often does not provide sufficient resolving power for attaining rewarding results. Comprehensive two-dimensional liquid chromatography is a technique of great analytical impact, since it offers much higher peak capacities than separations in a single dimension. In the present review, we describe applications in the field of comprehensive two-dimensional liquid chromatography for polyphenol analysis in real-world food samples. Comprehensive two-dimensional liquid chromatography applications to nonfood matrices fall outside the scope of the current report and will not be discussed.

Comprehensive two-dimensional liquid chromatography-tandem mass spectrometry for the simultaneous determination of wine polyphenols and target contaminants.

A novel system for comprehensive two-dimensional liquid chromatography coupled to a triple quadrupole mass spectrometer is described for the analysis of wine components. The first dimension consisted of a 250-mm microbore cyano column utilizing 5µm diameter particles, interfaced to a 50-mm superficially-porous particle C18 column with 2.7µm diameter particles. Both columns were operated under reversed-phase conditions. Correlation between the two chromatographic separation modes was decreased by designing a 60-s shift gradient program in the second dimension, and the increase in orthogonality was evaluated quantitatively utilizing a number of orthogonality metrics. The system was employed for the analysis of a red wine sample, without preliminary clean-up procedures, and a total of 43 polyphenols were separated and identified. Comparison with a one-dimensional LC system showed a large increase in the number of identified components with the two-dimensional system. Optimized multiple reaction monitoring experiments allowed for the determination of trans-resveratrol, which is one of the most active antioxidant component of wine, and for monuron, a plant protection product (herbicide) of interest to regulatory agencies. The estimated limits of detection and of quantification were 0.3µgL(-1) and 1µgL(-1), respectively, well below the minimum detection limit (10µgL(-1)) set by current regulation.

Rapid isolation, reliable characterization, and water solubility improvement of polymethoxyflavones from cold-pressed mandarin essential oil.

Polymethoxyflavones possess many biological properties, as lipid-lowering, hypoglycaemic, anti-inflammatory, antioxidant, and anticancer activities, therefore, they may be employed as nutraceuticals or therapeutic agents. The scarcity of pure polymethoxyflavones on the market as well as their low water solubility limited in vivo studies and the use of polymethoxyflavones as food or pharmaceutical supplements. Since mandarin peels are a rich source of polymethoxyflavones, tangeretin, nobiletin, sinensetin, tetra-O-methyl scutellarein, and heptamethoxyflavone were purified from a nonvolatile residue of a cold-pressed mandarin essential oil using a multidimensional preparative liquid chromatographic system coupled with a photodiode array detector and a single quadrupole mass spectrometer. A new prototype, consisting of a nano-liquid chromatography system coupled with an electron ionization mass spectrometer, was used for the characterization of the pure isolated molecules. Finally, due to the collection of highly pure nobiletin and tangeretin, the ability of 2-hydroxypropyl-ß-cyclodextrin to enhance the water solubility of both polymethoxyflavones was evaluated by phase solubility studies and Job's plot method.

Diet and Inflammation: Possible Effects on Immunity, Chronic Diseases, and Life Span.

Chronic inflammation negatively impacts all physiological functions, causing an array of degenerative conditions including diabetes; cancer; cardiovascular, osteo-articular, and neurodegenerative diseases; autoimmunity disorders; and aging. In particular, there is a growing knowledge of the role that gene transcription factors play in the inflammatory process. Obesity, metabolic syndrome, and diabetes represent multifactorial conditions resulting from improper balances of hormones and gene expression. In addition, these conditions have a strong inflammatory component that can potentially be impacted by the diet. It can reduce pro-inflammatory eicosanoids that can alter hormonal signaling cascades to the modulation of the innate immune system and gene transcription factors. Working knowledge of the impact of how nutrients, especially dietary fatty acids and polyphenols, can impact these various molecular targets makes it possible to develop a general outline of an anti-inflammatory diet that offers a unique, nonpharmacological approach in treating obesity, metabolic syndrome, and diabetes. Several important bioactive dietary components can exert their effect through selected inflammatory pathways that can affect metabolic and genetic changes. In fact, dietary components that can modulate glucose and insulin levels, as well as any other mediator that can activate nuclear factor-kB, can also trigger inflammation through common pathway master switches.

Performance evaluation of a versatile multidimensional chromatographic preparative system based on three-dimensional gas chromatography and liquid chromatography-two-dimensional gas chromatography for the collection of volatile constituents.

The present research deals with the multi-collection of the most important sesquiterpene alcohols belonging to sandalwood essential oil, as reported by the international regulations: (Z)-α-santalol, (Z)-α-trans bergamotol, (Z)-ß-santalol, epi-(Z)-ß-santalol, α-bisabolol, (Z)-lanceol, and (Z)-nuciferol. A versatile multidimensional preparative system, based on the hyphenation of liquid and gas chromatography techniques, was operated in the LC-GC-GC-prep or GC-GC-GC-prep configuration, depending on the concentration to be collected from the sample, without any hardware or software modification. The system was equipped with a silica LC column in combination with polyethylene glycol-poly(5% diphenyl/95% dimethylsiloxane)-medium polarity ionic liquid or ß-cyclodextrin based GC stationary phases. The GC-GC-GC-prep configuration was exploited for the collection of four components, by using a conventional split/splitless injector, while the LC-GC-GC-prep approach was applied for three low abundant components (<5%), in order to increase the quantity collected within a single run, by the LC injection of a high sample amount. All target compounds, whose determination is hampered by the unavailability of commercial standards, were collected at milligram levels and with a high degree of purity (>87%).

Non-polar lipids characterization of Quinoa (Chenopodium quinoa) seed by comprehensive two-dimensional gas chromatography with flame ionization/mass spectrometry detection and non-aqueous reversed-phase liquid chromatography with atmospheric pressure chemical ionization mass spectrometry detection.

A chemical characterization of major lipid components, namely, triacylglycerols, fatty acids and the unsaponifiable fraction, in a Quinoa seed lipids sample is reported. To tackle such a task, non-aqueous reversed-phase high-performance liquid chromatography with mass spectrometry detection was employed. The latter was interfaced with atmospheric pressure chemical ionization for the analysis of triacylglycerols. The main triacylglycerols (>10%) were represented by OLP, OOL and OLL (P = palmitoyl, O = oleoyl, L = linoleoyl); the latter was present in the oil sample at the highest percentage (18.1%). Furthermore, fatty acid methyl esters were evaluated by gas chromatography with flame ionization detection. 89% of the total fatty acids was represented by unsaturated fatty acid methyl esters with the greatest percentage represented by linoleic and oleic acids accounting for approximately 48 and 28%, respectively. An extensive characterization of the unsaponifiable fraction of Quinoa seed lipids was performed for the first time, by using comprehensive two-dimensional gas chromatography with dual mass spectrometry/flame ionization detection. Overall, 66 compounds of the unsaponifiable fraction were tentatively identified, many constituents of which (particularly sterols) were confirmed by using gas chromatography with high-resolution time-of-flight mass spectrometry.

Functional and metabolic disorders in celiac disease: new implications for nutritional treatment.

Celiac disease (CD) is a chronic disease causing the inflammation of the proximal small intestine, in genetically predisposed individuals. This is triggered by the consumption of the gluten protein and the side effects of the disease are mitigated by a lifelong gluten-free diet (GFD) treatment. The predominant consequence of CD is malnutrition due to malabsorption (with diarrhea, weight loss, nutritional deficiencies, and altered blood parameters), especially in patients who do not show strict adherence to GFD treatment. Recent evidence shows that, despite a lifelong GFD, some functional disorders persist, such as compromised gallbladder function and motility, exocrine pancreatic insufficiency, increased gut permeability, small-intestinal bowel overgrowth, nonalcoholic fatty liver disease (NAFLD), lactose intolerance, and milk allergy. These abnormalities may predispose to the occurrence of overweight and obesity even in CD patients. This review focuses on the principal functional and metabolic disorders in both treated and untreated CD, ranging from alterations of the gastrointestinal system to impaired glucose and lipid metabolism and insulin secretion with the aim of providing new implications beyond a GFD, for an ad hoc nutrition treatment in these patients.

Food fried in extra-virgin olive oil improves postprandial insulin response in obese, insulin-resistant women.

The benefits of low glycemic load (GL) diets on clinical outcome in several metabolic and cardiovascular diseases have extensively been demonstrated. The GL of a meal can be affected by modulating the bioavailability of carbohydrates or by changing food preparation. We investigated the effect on plasma glucose and insulin response in lean and obese women of adding raw or fried extra-virgin olive oil to a carbohydrate-containing meal. After an overnight fast, 12 obese insulin-resistant women (body mass index [BMI], 32.8 ± 2.2 kg/m(2)) and five lean subjects (BMI, 22.2 ± 1.2 kg/m(2)) were randomly assigned to receive two different meals (designated A and B). Meal A was composed of 60 g of pasta made from wheat flour and 150 g of grilled courgettes with 25 g of uncooked oil. Meal B included 15 g of oil in the 150 g of deep-fried courgettes and 10 g of oil in the 60 g of stir-fried pasta. Both meals included 150 g of apple. Blood samples were collected at baseline and every 30 minutes over a 3-hour post-meal period and were tested for levels of glucose, insulin, C-peptide, and triglycerides. The area under the curve (AUC) values were calculated. In obese women the AUCs for C-peptide were significantly higher after meal A than after meal B at 120 minutes (W [Wilcoxon sign rank test] = 27.5, P = .0020), 150 minutes (W = 26.5, P = .0039), and 180 minutes (W = 26.5, P = .0039). No differences were found in lean subjects. This study demonstrated that in obese, insulin-resistant women, food fried in extra-virgin olive oil significantly reduced both insulin and C-peptide responses after a meal.

Increased serum high-density lipoprotein-cholesterol concentration in celiac disease after gluten-free diet treatment correlates with body fat stores.

BACKGROUND: Low high-density lipoprotein-cholesterol (HDL-C) concentration correlates with increased cardiovascular risk. A great prevalence of celiac disease (CD) was reported among patients with low HDL-C concentration, and gluten-free diet (GFD) treatment seems to normalize lipid profile. We evaluated blood lipids and body composition in 26 CD patients with low HDL-C level (<1.0 mmol/L) at diagnosis and after GFD. STUDY: A case-control study. METHODS: The diagnosis was based on histologic evidence of subtotal or total duodenal villous atrophy. Patients were studied before and after GFD treatment (14.2+/-1.4 mo) with biopsy-proven return to normal of the duodenal mucosa. HDL-C was enzymatically assessed after precipitation of very low-density lipoprotein and low-density lipoprotein with heparin-magnesium. Apolipoprotein (Apo)-AI level was assessed by immunoturbidimetric assay; triglycerides by an enzymatic colorimetric method. Body composition was assessed by dual-energy x-ray absorptiometry. RESULTS: Body composition improved after GFD, with increasing body weight (P<0.05) essentially owing to increased fat mass (FM) (P<0.01), rather than fat-free mass (P=0.064). Total cholesterol and HDL-C were lower in untreated compared with treated patients (P<0.001 and P<0.0001). Apo-AI level increased significantly after GFD (1.20+/-0.22 vs. 1.46+/-0.17 g/L; P<0.0001). Apo-AI, sex, and FM were all significant determinants of HDL-C level; a positive correlation (R=0.68; P<0.0001) was found between increase in HDL-C level and in FM after GFD treatment. CONCLUSIONS: Restoration of lipid profile in CD patients after GFD treatment may be explained by an increase in both Apo-AI secretion by intestinal cells and body fat stores.

Metabolic and nutritional features in adult celiac patients.

Celiac disease (CD) is a chronic immune-mediated gluten-dependent enteropathy induced by ingestion of gluten-containing products, characterized by intestinal malabsorption and subtotal or total atrophy of intestinal villi, which improves after gluten-free diet (GFD). Untreated patients affected by the classic form of CD are at high risk of malnutrition, but an impairment of nutritional status is frequently reported also in patients with the subclinical form of the disease. Strict adherence to a GFD greatly improves nutritional status, inducing an increase in fat and bone compartments, but does not completely normalize body composition. A lack of improvement in nutritional status may identify incomplete adherence to GFD treatment. Evidence has shown lower body weights and lower fat mass and fat-free mass contents in CD patients. Untreated CD patients oxidize more carbohydrates as energy substrate compared to treated subjects. In addition, circulating ghrelin concentration was reduced after GFD treatment as a possible consequence of body composition improvement, while leptin did not correlate with the changes in body composition and substrate oxidation in patients with CD. A significant correlation was reported between ghrelin and the degree of severity of intestinal mucosal lesions. CD patients might show an alteration in lipid metabolism, i.e. low serum total and high- density lipoprotein-cholesterol as a consequence of lipid malabsorption and decreased intake. In conclusion, weight loss and nutritional deficiencies are relevant clinical features in CD. Thus, an early and accurate evaluation of nutritional status and energy metabolism represents a fundamental tool in the management of CD patients.

Relationship between changes in platelet reactivity and changes in platelet receptor expression induced by physical exercise.

INTRODUCTION: In previous studies we have consistently shown a significant increase of platelet reactivity after exercise in patients with obstructive coronary artery disease (CAD). We also observed a significant individual variability in the response to exercise of platelet reactivity in these patients. Whether exercise-induced changes in platelet reactivity correlate with changes in platelet membrane receptors in patients with CAD is unknown. METHODS: We studied 26 patients with stable CAD and 10 matched healthy controls who underwent a symptom-limited treadmill exercise stress test. Venous blood samples were collected at rest and within 5 min of peak exercise. Platelet reactivity was measured by the PFA-100 method as time to occlude (closure time, CT) a ring coated with collagen/adenosine diphosphate (C/ADP). Platelet expression of glycoprotein (GP) IIb/IIIa, in both global (CD41) and active form (PAC-1), and P-selectin (CD62P) and formation of leukocyte-platelet aggregates were assessed by flow cytometry. RESULTS: After exercise CT did not change in controls (85.4+/-12 to 84.0+/-9 s, p=0.37), whereas it decreased in CAD patients (98.8+/-24 to 91.4+/-25 s, p<0.001). After exercise, CD41 and PAC-1 platelet expression increased significantly in CAD patients (p=0.04 for both), but not in controls (p=0.39 and p=0.98, respectively). To evaluate the relationship between the response to exercise of platelet reactivity and of platelet receptor expression, CAD patients were divided into two groups: CAD group 1 (16 patients, decrease in CT >5 s after exercise) and CAD group 2 (10 patients no increase in platelet reactivity after exercise). CD41 and PAC-1 expression increased in CAD group 1 (p=0.008 and p=0.026, respectively) but not in CAD group 2 (p=0.39 and p=0.50, respectively). No significant differences were observed between the 2 groups for changes in CD62P and leukocyte-platelet aggregates. CONCLUSIONS: Our data show that, in patients with stable CAD, an increased platelet reactivity to C/ADP stimulation after exercise, as assessed by the PFA-100 method, is specifically associated with an increased expression of platelet GP IIb/IIIa receptor.

Relationship between ghrelin levels, alcohol craving, and nutritional status in current alcoholic patients.

BACKGROUND: Ghrelin is a peptide produced mainly by the gut and hypothalamus. Ghrelin is able to stimulate food-seeking behavior. Alcohol-craving and food-seeking behavior could share common neural circuits. Ghrelin is related to nutritional status, but few data are available in alcoholic patients on the relationship between ghrelin and nutritional disorders. METHODS: Plasma ghrelin was evaluated in 15 current alcoholic male patients compared with 15 healthy male volunteers. Craving was evaluated by the Obsessive-Compulsive Drinking Scale. Body composition was assessed by dual-energy X-ray absorptiometry. Energy substrate utilization was evaluated by indirect calorimetry. RESULTS: Ghrelin was significantly reduced in alcohol-dependent patients with respect to healthy subjects (p=0.0278). A significant positive correlation was found between ghrelin and craving (r=0.55; p=0.034). A preferential utilization of lipids as an energy substrate with a reduction of the fat mass (p=0.01) and an increase of the free fat mass (p=0.0091) was found in alcoholic patients. CONCLUSIONS: Within our sample showing low ghrelin levels probably related to the impaired nutritional status; patients with higher levels of ghrelin showed higher levels of alcohol craving. These preliminary data indicate that ghrelin could be implicated in the neurobiological mechanisms of alcohol craving, other than a hormone influenced by the nutritional status.

Reduced plasma ghrelin concentration in celiac disease after gluten-free diet treatment.

OBJECTIVE: Celiac disease (CD) is characterized by malabsorption, weight loss and increased energy expenditure. The aim of this study was to investigate the relationship between circulating ghrelin and leptin, which are produced at gastrointestinal level and are involved in energy balance regulation, and changes in body composition and energy metabolism in CD patients before and after gluten-free diet (GFD)-induced restoration of the intestinal mucosa. MATERIAL AND METHODS: Body composition (by dual-energy X-ray absorptiometry), resting metabolic rate and substrate oxidation rates (by indirect calorimetry) were assessed in 18 adult women with the classic form of CD (age 31.4 +/- 7.8 years, body mass index (BMI) 20.6 +/- 2.1 kg/m2) before and at least 2 years after GFD treatment and in 22 age-matched healthy women (age 33.1 +/- 7.2 years, BMI 22.9 +/- 2.1 kg/m2). Plasma leptin and ghrelin concentrations were assessed by the ELISA and RIA procedures, respectively. RESULTS: Fat-free mass was reduced before and after GFD compared to control subjects (p < 0.01), while fat mass increased after treatment (p < 0.01). Plasma leptin concentration was similar between groups and correlated only with BMI (r = 0.84; p < 0.0001) and percentage body fat (r = 0.86; p < 0.0001). Circulating ghrelin levels (pg/ml) were similar between untreated patients and control subjects, but decreased after GFD treatment (untreated CD: 282.6 +/- 55.5 versus treated 109.2 +/- 49.9; p < 0.0001 and versus control subjects 262.2 +/- 30.0; p < 0.0001) and were negatively correlated with BMI in CD patients (r = -0.32; p < 0.01). CONCLUSIONS: The low plasma ghrelin concentration found in CD patients after GFD treatment could only be partially explained by the slight increase in body-weight and fat mass. Further studies are needed to better ascertain the role played by an incomplete functional or quantitative recovery of ghrelin-producing cells in CD.