Untargeted Plasma Metabolomics Unravels a Metabolic Signature for Tissue Sensitivity to Glucocorticoids in Healthy Subjects: Its Implications in Dietary Planning for a Healthy Lifestyle.

In clinical practice, differences in glucocorticoid sensitivity among healthy subjects may influence the outcome and any adverse effects of glucocorticoid therapy. Thus, a fast and accurate methodology that could enable the classification of individuals based on their tissue glucocorticoid sensitivity would be of value. We investigated the usefulness of untargeted plasma metabolomics in identifying a panel of metabolites to distinguish glucocorticoid-resistant from glucocorticoid-sensitive healthy subjects who do not carry mutations in the human glucocorticoid receptor (NR3C1) gene. Applying a published methodology designed for the study of glucocorticoid sensitivity in healthy adults, 101 healthy subjects were ranked according to their tissue glucocorticoid sensitivity based on 8:00 a.m. serum cortisol concentrations following a very low-dose dexamethasone suppression test. Ten percent of the cohort, i.e., 11 participants, on each side of the ranking, with no NR3C1 mutations or polymorphisms, were selected, respectively, as the most glucocorticoid-sensitive and most glucocorticoid-resistant of the cohort to be analyzed and compared with untargeted blood plasma metabolomics using gas chromatography-mass spectrometry (GC-MS). The acquired metabolic profiles were evaluated using multivariate statistical analysis methods. Nineteen metabolites were identified with significantly lower abundance in the most sensitive compared to the most resistant group of the cohort, including fatty acids, sugar alcohols, and serine/threonine metabolism intermediates. These results, combined with a higher glucose, sorbitol, and lactate abundance, suggest a higher Cori cycle, polyol pathway, and inter-tissue one-carbon metabolism rate and a lower fat mobilization rate at the fasting state in the most sensitive compared to the most resistant group. In fact, this was the first study correlating tissue glucocorticoid sensitivity with serine/threonine metabolism. Overall, the observed metabolic signature in this cohort implies a worse cardiometabolic profile in the most glucocorticoid-sensitive compared to the most glucocorticoid-resistant healthy subjects. These findings offer a metabolic signature that distinguishes most glucocorticoid-sensitive from most glucocorticoid-resistant healthy subjects to be further validated in larger cohorts. Moreover, they support the correlation of tissue glucocorticoid sensitivity with insulin resistance and metabolic syndrome-associated pathways, further emphasizing the need for nutritionists and doctors to consider the tissue glucocorticoid sensitivity in dietary and exercise planning, particularly when these subjects are to be treated with glucocorticoids.

Paraoxonase (PON)-1 activity in septic neonates: One more arrow in the quiver of biomarkers of neonatal sepsis?

Paraoxonase-1 (PON-1), a calcium ion-dependent high-density lipoprotein (HDL)-associated enzyme, has been proposed as a negative acute phase reactant biomarker in animal and human adult studies. The aim of this study was to evaluate the value of PON-1 activity in the diagnosis and monitoring of neonatal sepsis. Serum PON-1 activity, as paraoxonase and arylesterase, was prospectively studied in 48 septic neonates and matched controls. PON-1 activity was decreased at the acute phase of sepsis in comparison with values at recovery and values in controls. Paraoxonase or arylesterase at enrollment correlated significantly with serum Amyloid-A, CRP and IL-6 and could also discriminate septic than non-septic neonates. In conclusion, our results are promising regarding the role of PON-1 as a biomarker of neonatal sepsis. Larger studies are needed to validate the clinical utility of PON-1 in neonatal medicine.

Effect of honey on glucose and insulin concentrations in obese girls.

BACKGROUND: Childhood obesity represents a major health problem of our century. The benefits of natural products, such as honey, in the management of obesity have gained renewed interest. In this study, we investigated the effect of honey on glucose and insulin concentrations in obese prepubertal girls. MATERIALS AND METHODS: Thirty healthy obese girls aged 10.55 (±SEM:0.34) years with a mean body mass index (BMI) above the 97th centile for age (28.58 ± 1.40 kg/m2 , BMI z-score 2.96) underwent a standard oral glucose tolerance test (OGTT) followed by an oral honey tolerance test (OHTT) 2 weeks later. Both solutions contained 75 g of glucose. Subsequently, subjects were randomized to receive either 15 g of honey or 15 g of marmalade daily, while both groups complied with dietetic instructions. Six months later all subjects were re-evaluated with an OGTT and an OHTT. RESULTS: At the end of the study, all subjects demonstrated a significant reduction in BMI (27.57 ± 1.40, z-score: 2.54 vs 28.58 ± 1.40 kg/m2 , z-score: 2.96, P < 0.001), however, there were no significant differences in BMI and all parameters tested between the group that received honey and the control group. The areas under the concentration-time curve for glucose and insulin for the entire population were significantly lower following ingestion of honey than glucose solution (P < 0.001) both at the beginning and at the end of study. CONCLUSIONS: These findings indicate that honey does not have an effect on stimulated plasma glucose and serum insulin concentrations compared with the standard glucose solution in obese prepubertal girls.

Salivary biomarkers may measure stress responses in critically ill children.

OBJECTIVE: Measurement of salivary biomarkers can provide important information regarding hypothalamic-pituitary-adrenal axis activity both under normal conditions as well as in response to psychological or physical stress. Our aim was to correlate salivary stress markers, such as cortisol, α-amylase and immunoglobulin A, with the Pediatric Risk Index Score of Mortality, underlying disease (pathologic, trauma and postoperative), need for mechanical ventilation/sedation and time lag between onset of illness and admission in children admitted in the pediatric intensive care unit. METHODS: We enrolled 79 pediatric intensive care unit patients (2-14 years) over a 2-year period, which satisfy the including criteria, but finally salivary biomarkers were evaluated in 65 patients. Saliva samples were collected within 24 h of admission at 8 a.m., 2 p.m. and 8 p.m. to examine potential disruption of circadian rhythm. RESULTS: Overall, the salivary biomarkers were increased; specifically, median values were (a) cortisol at 8 a.m.: 50.04 nmol/L, 2 p.m.: 30.69 nmol/L and 8 p.m.: 247.12 nmol/L; (b) α-amylase: at 8 a.m.: 22.567 U/L; 2 p.m.: 22.702 U/L and 8 p.m.: 21.484 U/L and (c) IgA at 8 a.m.: 95.10 mg/dL, 2 p.m.: 88.55 mg/dL and 8 p.m.: 80.80 mg/dL. Significantly higher levels were demonstrated in children younger than 6 years and those with Pediatric Risk Index Score of Mortality ⩾8 upon admission. Disturbances in circadian rhythm were observed. Cortisol circadian rhythm disturbance was observed only in children with Pediatric Risk Index Score of Mortality score ⩾8 upon admission while maintaining normal α-amylase circadian rhythm, which was associated with less than 3 days hospitalization in pediatric intensive care unit. No daily variance in IgA was observed. CONCLUSION: Salivary biomarkers may serve, in critically ill children, as a sensitive, non-invasive method, important for the early recognition of those at high risk and guiding intervention, before clinical deterioration, promoting the quality of health care in pediatric population.

Thrombocytopenia in critically ill patients with severe sepsis/septic shock: Prognostic value and association with a distinct serum cytokine profile.

PURPOSE: The purpose of the study is to evaluate the incidence, association with serum cytokine profile, and prognostic value of thrombocytopenia, in critically ill patients with severe sepsis/septic shock. METHODS: A cohort of 105 consecutive patients admitted in intensive care unit was included in our analysis. Serum levels of intercellular adhesion molecule, vascular cell adhesion molecule, interferon γ, interleukin 8, and soluble form of the urokinase-type plasminogen activator receptor (suPAR) were measured. RESULTS: Thrombocytopenia was observed in 53% of patients at the time of admission. Platelet counts showed a statistically significant negative correlation with serum levels of intercellular adhesion molecule, suPAR, and interleukin 8 (P < .0001). In multivariate analysis, high Acute Physiological and Chronic Health Evaluation II score, high serum suPAR, and low platelet counts were associated with increased mortality, and receiver operating characteristic curve analysis was used to determine the best cutoff value for mortality prediction. Each variable with a value above or below the predefined cutoff levels were given 1 point. Patients were categorized in risk groups based on total point score. High-risk (2-3), intermediate-risk (1), and low-risk (0 points) groups consisted of 43%, 22%, and 35% and 28-day mortality was observed in 69%, 26%, and 3% of the patients in each group, respectively. CONCLUSION: Thrombocytopenia is associated with poor prognosis and a distinct serum cytokine profile.

Incretins, amylin and other gut-brain axis hormones in children with coeliac disease.

BACKGROUND: Previous research indicated that coeliac disease (CD) is associated with type 1 diabetes mellitus (T1DM). However, the gut-brain axis peptide hormones secretion has not been evaluated so far in patients with CD prior to treatment initiation or under treatment, irrespective of patients having concomitant T1DM or not. The aim of the study was therefore to evaluate these gut hormones at the preprandial levels of patients with CD before and under treatment. METHODS: Of forty-seven CD children, 12 untreated (UCD), 22 treated with gluten-free diet (TCD) and 13 treated CD with coexisting T1DM (DCD), and 18 healthy controls (HC) were enrolled. Preprandial glucagon-like-peptide-1 (GLP-1), glucose-dependent-insulinotropic-polypeptide (GIP), active amylin, acylated ghrelin (AG), leptin, pancreatic polypeptide (PP) and peptide-tyrosine-tyrosine (PYY) were determined with hormone-map-array technology. RESULTS: We found in patients with CD compared with HC that the concentration of (i) GLP-1 was reduced remarkably in all patients with CD (P = 0.008), (ii) GIP was lower in patients with UCD (P = 0.008), (iii) amylin was remarkably reduced (P < 0.01) in all patients with CD, (iv) AG was significantly decreased in patients with DCD (P < 0.01), while (v) leptin, PP and PYY were not significantly different. GIP, GLP-1 and amylin levels correlated positively with insulin concentrations (P < 0.001, P = 0.004 and P < 0.01, respectively) in all patients. Amylin and GIP levels were strongly associated with triglycerides concentrations (P < 0.001, for both peptides) in children with CD. CONCLUSIONS: Our study revealed a different secretion pattern of gut-brain axis hormones in children with CD compared with HC. The alterations in the axis were more pronounced in children with both CD and T1DM.

Correlation of NT-proBNP levels and cardiac iron concentration in patients with transfusion-dependent thalassemia major.

Iron-induced cardiotoxicity remains the leading cause of morbidity and mortality in patients with transfusion-dependent ß-thalassemia major. Heart failure in these patients, which may be reversible but has a poor prognosis, is characterized by myocardial iron deposition-related early diastolic dysfunction. Amino-terminal pro-brain natriuretic peptide (NT-proBNP) is a sensitive biomarker for the detection of asymptomatic left ventricular dysfunction. In this study, we prospectively evaluated plasma NT-proBNP levels in 187 adult patients aged 19-54 years with ß-TM. Possible correlations with the proposed recently cardiac iron concentration based on an equation derived from heart T2* assessment by MRI: [Fe] = 45.0 × [T2*](-1.22) with [Fe] in milligrams per gram dry weight and T2* in milliseconds were explored. We found that: 143 patients had no cardiac hemosiderosis, defined as [Fe] < 1.1 mg/g dry weight, corresponding to T2* > 20 ms and 44 patients had cardiac hemosiderosis, defined as [Fe] > 1.2mg/g dry weight. The main results of the study showed that: a) NT-proBNP levels were markedly increased in thalassemic patients (152.2 ± 190.1 pg/mL, ranged from 6.0 to 1336.0 pg/mL compared to normal control levels 40.1 ± 19.7 pg/mL, p < 0.001, b) NT-proBNP levels were significantly higher in patients with cardiac hemosiderosis compared to patients without cardiac hemosiderosis (185.1 ± 78.0 vs 128.9 ± 20.2 pg/mL, p < 0.05), c) NT-proBNP levels correlated with [Fe] values (r = 0.387, p < 0.001). This correlation was significant in patients with cardiac hemosiderosis (r = 0.520, p < 0.001), but not in patients without cardiac hemosiderosis (p > 0.1), and d) no significant correlation was found between NT-proBNP levels and left ventricular ejection fraction values, (p > 0.3). Our study demonstrated for first time the significant association of NT-proBNP levels and cardiac iron concentration in patients with ß-thalassemia major linking blood chemistry and imaging techniques. Multicenter studies of these parameters during iron chelation therapies are needed to validate their association and further exploit its clinical use.

Cytokine response to diabetic ketoacidosis (DKA) in children with type 1 diabetes (T1DM).

It has been suggested that cytokine release during DKA may result in capillary perturbation and thus may contribute to the development of its acute clinical complications (i.e.cerebral or pulmonary edema). We studied in 38 newly diagnosed T1DM children with DKA, aged 7.68±3.07 years, plasma levels of cytokines IL-1ß (interleukin-1ß), IL-2, IL-6, IL-8, IL-10, TNF-α (tumour necrosis factor-α) and also WBC (white blood cell count), hs-CRP (high sensitivity C-reactive protein), GH (growth hormone) and cortisol, prior to, during and 120h after DKA management, with the aim to monitor their levels at different time-points and in different degrees of DKA severity. Prior to DKA management the levels of IL-6, IL-8, IL-10, WBC and cortisol were elevated, but were all reduced within 120 h after DKA management. Then the patients were divided into two groups: a. moderate/severe: pH≤7.2, b. mild DKA: pH>7.2. In the group with moderate/severe DKA (ph≤7.2), IL-10 levels were the highest of all cytokines, but were significantly decreased after 6h (91.76 vs 18.04 pg/mL, p=0.008), with no further change, while IL-6 levels were decreased at 120 h (28.32 vs 11.9 pg/mL, p=0.003). The above were not observed in the group with mild DKA. In conclusion, in the children with DKA of our study, in the group with moderate/severe DKA the IL-10 levels were prematurely reduced at 6 hours, while the IL-6 levels remained high and were reduced at 120 hours after the DKA management. These changes may be responsible for increased capillary perturbation, which could lead to the subsequent development of acute DKA complications.

Plasma proteomic analysis in obese and overweight prepubertal children.

BACKGROUND: Childhood obesity represents one of the most challenging health problems of our century and is associated with significant morbidity and mortality in adult life. Proteomics is a large-scale analysis of proteins, which provides, information on protein expression levels, post-translational modifications, subcellular localization and interactions. OBJECTIVE: To investigate whether obesity in childhood is associated with alterations in plasma protein expression profiles. METHODS: Plasma samples from 10 obese [age: 10·75 ± 0·16 year; body mass index (BMI): 27·50 ± 0·69 kg m(-2) ], 10 overweight (age: 10·54 ± 0·1 year; BMI: 21·88 ± 0·28 kg m(-2) ) and 10 normal-weight (age: 10·89 ± 0·19 year; BMI: 18·34 ± 0·42kg m(-2) ) prepubertal boys were subjected to protein fractionation and analysed by two-dimensional electrophoresis, followed by protein identification using matrix-assisted laser desorption time-of-flight mass spectrometry. Fasting plasma glucose and serum insulin, lipid and apolipopoprotein concentrations were determined in all subjects. RESULTS: The expression of apolipoprotein (Apo) A-I (ApoA-I) was significantly lower in obese and overweight children compared with children of normal BMI (P < 0·05). The expression of ApoE was significantly lower in overweight compared with normal-weight children (P < 0·05), while that of ApoA-IV was significantly higher in obese children compared with their normal counterparts (P < 0·01). Serum ApoA-I concentrations were significantly lower in obese (147 ± 4·27mg dL(-1) ) and overweight (145·5 ± 9·65mg dL(-1) ) than in normal-weight (157 ± 8·77mg dL(-1) ; P = 0·036) children. CONCLUSIONS: Obese and overweight prepubertal children demonstrated prominent alterations in the expression of plasma apolipoproteins compared with their normal counterparts. Low ApoA-I plasma expression levels and serum concentrations in obesity might be present in childhood before any significant alterations in total or high-density lipoprotein-cholesterol concentrations are documented. We recommend that serum ApoA-I concentrations are determined in all overweight and obese children.

Early effects of sodium valproate monotherapy on serum paraoxonase/arylesterase activities.

OBJECTIVE: Valproic acid (VPA) treatment and paraoxonase1/arylesterase (PON1/Aryl) activities are related to the production of free radicals. Our aim was to study the PON1/Aryl activities in children on VPA therapy. MATERIAL AND METHODS: Thirty-two children with seizures and 30 healthy child volunteers took part. Ill children underwent the common laboratory tests, as well as total antioxidant status (TAS), total oxidant status (TOS), lipid profile, liver enzymes and PON1/Aryl activities pre- and post-60 days on VPA therapy (30 mg/kg/24 h), whereas the healthy children were tested just once. RESULTS: None of the studied biochemical parameters differed between volunteers and children with seizures pretreatment. Liver enzymes, lipids and TOS levels (124+/-30 versus 580+/-40 micromol/L; p<0.001) were significantly elevated, whereas the activities of PON1/Aryl (146+/-43 versus 118+/-40 U/mL/min 120+/-42 versus 98+/-38 KU/mL/min; p<0.01) and TAS levels (436+/-42 versus 288+/-39 micromol/L; p<0.001) were decreased in children after treatment. Additionally, strong negative correlations were found between PON1/Aryl activities, liver enzymes, TOS (r = -0.69) and VPA levels (r = -0.57), whereas PON1/Aryl activities correlated positively with TAS, HDL and Apo A-I in all groups. CONCLUSIONS: Serum PON1/Aryl activities were decreased after 60 days on VPA treatment, probably due to liver dysfunction and free radicals production by VPA, without excluding the possibility of a direct action of the drug on the enzymes.

The effect of diet on Paraoxonase 1/Arylesterase activities in patients with disorders of galactose metabolism.

OBJECTIVE: To investigate the effects of diet on the antiatherogenic enzyme Paraoxonase 1/Arylesterase (PON1/Aryl) activities in patients with disorders of galactose metabolism. PATIENTS AND METHODS: Eleven poorly dietary controlled children with classical galactosaemia (GALT deficiency), 7 with epimerase deficiency and 12 with duarte 1 variant 'off diet' underwent clinical and laboratory investigations before and after 10 days on galactose restricted diet whereas controls (N = 20) were examined once. Serum lipids, lipoproteins and apolipoprotein A1 (ApoA1) were measured with routine methods, PON1/Aryl activities and total antioxidant status (TAS) spectrophotometrically, and galactose-1-phosphate (Gal-1-P) enzymatically. RESULTS: Lipids, lipoproteins, ApoA1, PON1/Aryl, TAS remained unaltered in all groups, except in those with classical galactosaemia pre- versus postdiet. In patients with classical galactosaemia, TAS, PON1, Aryl (0.98 +/- 0.2 mmol/l, 60 +/- 12 U/min/ml, 56 +/- 16 KU/min/ml, respectively) were significantly reduced prediet as compared with those postdiet (1.63 +/- 0.2 mmol/l, 136 +/- 15 U/min/ml, 112 +/- 18 KU/min/ml, respectively; P < 0.001) and controls. The enzyme activities positively correlated with TAS (r = 0.56, P < 0.001) in all groups and negatively with Gal-1-P (r = -0.54, P < 0.001) in group with GALT deficiency. CONCLUSIONS: Low TAS and high Gal-1-P levels may reduce PON1/Aryl activities. Patients with classical galactosaemia, when on strict diet, may benefit with a generous antiatherogenic capacity.

Circulating levels of adhesion molecules and markers of endothelial activation in acute inflammation induced by prolonged brisk exercise.

OBJECTIVES: To investigate circulating levels of adhesion molecules and markers of endothelial activation in acute inflammation induced by prolonged brisk exercise. DESIGN AND METHODS: The circulating levels of adhesion molecules E-, L- and P-selectins, intercellular and vascular adhesion molecule-1 (ICAM-1 and VCAM-1), along with those of thrombomodulin (TM), N-terminal pro-brain natriuretic peptide (NT-pro-BNP) and cardiac troponin T, were measured before, at the end of and at 48 h post-race, in athletes participating in this extreme physical stress paradigm. RESULTS: Levels of L- and P-selectins remained the same before and at the end of the "Spartathlon" race, presenting a similar decline at 48 h post-race. E-Selectin, ICAM-1 and TM reached a maximum value at the end of the race and returned to normal 48 h after the race. A similar profile was observed for VCAM-1 and NT-pro-BNP, with a tendency for a decrease at 48 h post-race, while troponin T was not detected. CONCLUSIONS: The indices of endothelial activation are strongly affected during "Spartathlon" race, suggesting that, although prolonged brisk exercise activates the endothelium, it rapidly recovers.

Maternal-neonatal serum paraoxonase 1 activity in relation to the mode of delivery.

AIM: To investigate the effect of the mode of labour and delivery on the total antioxidant status (TAS) and the paraoxonase 1 (PON 1) serum activity in mothers and their newborns. SUBJECTS AND METHODS: One hundred six women with normal pregnancy were divided into 4 groups: group A (n = 28) with normal labour and vaginal delivery (VG), group B (n = 25) with scheduled caesarean section (CS), group C (n = 26) with "emergency" CS and group D (n = 27) with prolonged labour + VG. Blood was obtained from the mothers at the beginning of the labour process and immediately after delivery (pre- and post-delivery) as well as from the umbilical cord (CB). PON 1 activity and blood chemistry were determined using the Bayer Advia 1650 Clinical Chemistry System, whereas TAS levels were measured spectrophotometrically at 450 min in microtiter plates. RESULTS: TAS levels were similar pre-delivery and low in CB in all the groups. In contrast, TAS levels were remarkably reduced in group C and in group D post-delivery whereas they were nearly unchanged in group B and just lowered in group A, at the same time of study. PON 1 activity was practically unaltered in group A and group B pre- vs. post-delivery. Interestingly, the enzyme activity was remarkably decreased in group C (222 +/- 16 vs. 153 +/- 14 U/min/mL) and group D (216 +/- 16 vs. 135 +/- 15 U/min/mL, p < 0.001) as compared with those of the other groups at the same time of study. Additionally, PON 1 activity was higher in the newborns of group A and group B than those in group C and group D. TAS and HDL positively correlated with PON 1 activity. CONCLUSION: The low TAS levels and the decreased PON 1 activity, which were found in groups C and D post-delivery, may be due to the increased production of free radicals, during long-lasting labour + VG and obstructive labour + CS. PON 1 activity was low in CB irrespectively of the mode of delivery, probably due to the low lipid levels in the serum of the umbilical cord. Neonates born with normal delivery or scheduled CS are benefited with a higher antiatherogenic enzyme activity perinatally.

Lipids, lipoproteins, apolipoproteins, selected trace elements and minerals in the serum of children on valproic acid monotherapy.

We evaluated the serum levels of lipids, lipoproteins, apolipoproteins, along with a number of minerals and trace elements such as Ca, Mg, Cu and Zn in a group of children after 6 months of valproic acid monotherapy. Thirty patients with seizures, mean age, 9.8+/-2.6 years and 79 healthy children (controls), mean age, 10.9+/-3.2 years, formed the two styd groups. The patient group was treated with valproic acid (27.9+/-14.8 mg/kg/24 hr). Patients underwent clinical and laboratory evaluations including liver function tests, NH3, lipid, mineral and selected trace element levels before and after six months on valproic acid treatment, whereas controls only one evaluation. Liver function data and NH3 levels were found to be elevated in the group of patients, whereas albumin level was reduced. Triglycerides, total cholesterol, HDL-C, apolipoprotein (ApoA)-1, Apo B and Ca concentrations were found relative to control values, LDL-C, VLDL-C, Mg, Cu, Zn, were measured significantly altered (P<0.0001) compared to controls. The ratios ApoA-1/ApoB, HDL-C/ApoA-1, LDL-C/Apo B, which were closely related to the size of LDL particles, where correlated with Zn/Cu (P<0.001). Serum lipid profile, especially LDL size, indirectly evaluated for the first time and metal levels were found to be significantly changed, after six months on valproic acid monotherapy, suggesting a possible risk of developing coronary heart disease. Since valproic acid is a long-term treatment, it could be recommended that the incorporation of measurements of lipids, lipoproteins, apolipoproteins and trace elements in the "follow up" laboratory testing could be a preventive measure.

The association of serum lipids, lipoproteins and apolipoproteins with selected trace elements and minerals in phenylketonuric patients on diet.

OBJECTIVE: Classical phenylketonuria (PKU) is an inborn error of metabolism characterized by high Phenylalanine (Phe) levels in blood and treated with a special low Phe diet which can be defined as "nonatherogenic". Since coronary heart disease (CHD) was reported to be a disease of zinc and copper imbalance, we aimed indirectly to evaluate the effect of the special diet on the size of LDL particles and to investigate whether some minerals and trace elements are involved in their lipoprotein metabolism. METHODS: Eighty-six (N=86) PKU patients were divided into two groups. Group A (N=44) on a strict diet and group B (N=42) who did not adhere to their treatment. Healthy children (N=98) were the controls. Serum total cholesterol (t-Chol), triacylglycerol, High-density lipoprotein (HDL) and t-Chol in very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) were measured with enzymatic methods, whereas Apolipoprotein AI (Apo AI), Apolipoprotein AII (Apo AII) and Apolipoprotein B (Apo B) were determined by nephelometric techniques. LDL/Apo B positively correlated with LDL size. Magnesium (Mg), calcium (Ca), copper (Cu) and zinc (Zn) measurements were performed by atomic absorption spectrometry. RESULTS: t-Chol, LDL, VLDL, Apo B, the ratio t-Chol/HDL, Apo AI/Apo B and LDL/Apo B as well as copper levels and the ratio Zn/Cu in group A statistically significantly differed as compared to those of group B and Controls. Positive correlations were found between Mg and HDL and Apo AI in all the groups whereas the mineral correlated with t-Chol, Apo B and the ratio LDL/Apo B only in the group A of patients. Copper negatively correlated with triacylglycerol, LDL, and Apo B and positively with t-Chol in group A. Zinc showed negative relationships in HDL and Apo A in all the studied groups. The ratio Zn/Cu negatively correlated with triacylglycerol and LDL in all the groups and positively with the ratios Apo AI/Apo B and LDL/Apo B in group A. CONCLUSION: Some of the minerals and trace elements were correlated with the lipids and lipoproteins and were also involved in the size of LDL particles in PKU patients on strict diet. Larger and less atherogenic LDL particles were associated with a high Zn/Cu ratio.