Insulin resistance and adiposity in relation to serum β-carotene levels.

Division of Pediatric Endocrinology and Metabolism, Nemours Children's Clinic, Jacksonville, FL 32207, USA.
The Journal of pediatrics (Impact Factor: 3.74). 02/2012; 161(1):58-64.e1-2. DOI: 10.1016/j.jpeds.2012.01.030
Source: PubMed

ABSTRACT To determine the effects of placebo vs an encapsulated supplement of fruit and vegetable juice concentrate (FVJC) on serum β-carotene levels, insulin resistance, adiposity, and subclinical inflammation in boys.
Thirty age-matched prepubertal boys (9 lean and 21 overweight (OW); age range, 6-10 years) were studied. All participants received nutrition counseling and were randomized to receive FVJC or placebo capsules for 6 months. Total cholesterol, triglycerides, lipid corrected β-carotene, serum retinol, glucose, insulin, retinol binding protein-4, leptin, adiponectin, leptin-to-adiponectin ratio, high-sensitivity C-reactive protein, and interleukin-6 were measured before and after the 6-month intervention. Homeostasis model assessment-insulin resistance (HOMA-IR), acute insulin response to intravenous glucose, along with abdominal fat mass (dual-energy x-ray absorptiometry) were also determined.
Baseline β-carotene concentrations correlated inversely with HOMA-IR, leptin-to-adiponectin ratio, and abdominal fat mass (P ≤ .01). FVJC intake increased β-carotene concentrations (P ≤ .001) but did not influence retinol or retinol binding protein-4. Retinol insufficiency <1.047 μM was present in 18% of the entire cohort at baseline and in 37% at 6 months. HOMA-IR decreased after supplementation in the OW cohort, when adjusted for percent weight change (P = .014). The percent change in abdominal fat mass increased in the placebo group and decreased in the FVJC group (P = .029).
A 6-month supplementation with FVJC in the presence of nutritional counseling was associated with an increase in serum β-carotene concentrations and a reduction in adiposity in conjunction with an improvement in insulin resistance in OW boys.

  • [Show abstract] [Hide abstract]
    ABSTRACT: We hypothesized that differences in red peppers pungencies and bioactive compounds are associated with different effects on obesity and glucose tolerance, and tested the hypothesis in ovariectomized (OVX) rats fed high fat diets. Increasing red pepper pungency was associated higher concentrations of capsaicin, dihydrocapsaicin and total capsaicinoids; and lower concentrations of β-carotene, total carotenoids and chlorogenic acid. After 8 weeks of consuming 1% different types of red peppers, moderately and severely pungent red peppers (MSP and SSP) improved energy homeostasis better than less pungent red pepper (LSP): MSP and SSP increased energy expenditure and decreased visceral fat mass. This was related to elevated uncoupling proteins (UCP)-1, UCP-2 and UCP-3 expressions and decreased expressions of genes involved in fatty acid synthesis. LSP enhanced insulin sensitivity and improved hepatic insulin signaling. In conclusion, red peppers with different color and pungency differently modulate energy and glucose homeostasis in OVX rats fed high fat diets.
    Journal of Functional Foods 03/2014; 7. DOI:10.1016/j.jff.2014.02.004 · 4.48 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective: To evaluate obese children and adolescents' retinol plasma levels and to correlate them with metabolic syndrome components. Methods: Cross-sectional study with 61 obese children and adolescents (body mass index Z score - ZBMI>+2). Pubertal development, arterial blood pressure, body weight and height for nutritional classification and waist circumference were obtained. A 15mL blood sample was collected (after a 12-hour fasting in a low luminosity room) for retinol determination (cut-off inadequate if <30µg/dL), lipid profile (HDL-c, LDL-c, and triglycerides), oral glucose tolerance test (fasting and 120 minutes) and for high sensitivity C-reactive protein. Spearman correlation and multiple linear regression were used in the statistical analysis. Results: Mean age was 10.7±2.7 years. There was a predominance of male gender 38/61 (62%) and pre-pubertal 35/61 (57%) subjects. The average plasmatic retinol was 48.5±18.6ug/dL. Retinol deficiency and severe obesity were observed in 6/61 (10%) and 36/61 (59%), respectively. Glucose level at 120 minutes was the independent and predictive variable of plasma retinol levels [β=-0.286 (95%CI -0.013 - -0.001)]. Conclusions: An independent and inverse association between plasma retinol levels and glucose tolerance was observed, suggesting an important contribution of this vitamin in the morbidities associated to obesity in children and adolescents.
    03/2014; 32(1):50-4. DOI:10.1590/S0103-05822014000100009
  • [Show abstract] [Hide abstract]
    ABSTRACT: There is continuously accruing evidence to suggest the health benefits of consuming fruits and vegetables. Food supplements may represent an effective and acceptable method to deliver a way of providing bioactive compounds to consumers. The aim of this work was to characterize the (poly)phenolic composition of three plant-based food supplements designed to integrate and increase the daily intake of dietary phenolics. The supplements are blends of berries, fruits, or vegetables made from a total of 36 different edible food plants. The best conditions for phenolic extraction were assessed and the total phenolic content of each supplement was estimated (it ranged from 50 to 176 mg/g powder). The analysis of the three supplements by uHPLC–MSn allowed to tentatively identify in all 119 (poly)phenolic compounds belonging to different classes, namely ellagitannins, gallotannins, dihydrochalcones, flavan-3-ols including proanthocyanidins, flavanones, flavones, flavonols, anthocyanins, hydroxybenzoic acids, hydroxycinnamic acids, phenylethanoids, and lignans. The contribution of these food supplements to the daily intake of (poly)phenolic compounds and, in turn, the potential contribution of such intake to health were discussed.
    01/2015; 3(2). DOI:10.1016/j.phanu.2015.01.001