A systematic review and meta-analysis of energy and macronutrient intake responses to physical activity interventions in children and adolescents with obesity.

BACKGROUND: The effects of regular physical activity on energy intake in obese adolescents are unknown. OBJECTIVE: The objective is to determine how physical activity interventions affect energy and macronutrient intake in overweight/obese youth. DATA SOURCES: Databases were searched from December 2014 to December 2015 for studies that measured energy and/or macronutrient consumption in response to physical activity intervention in overweight/obese youth. DATA SELECTION: The review comprises primary source articles published in English in peer-reviewed journals. Articles that presented data on energy and/or macronutrient intake before and after a physical activity intervention (without dietary restriction) in overweight or obese children and teenagers (up to 18 years old) were included. Of the initial 307 references found, nine were included. RESULTS: The nine included studies analysed the effect of 15 different physical activity interventions. Nine showed a decrease and six unchanged energy intakes. The effect size for total energy intake ranged from -2.108 to -0.207 (n = 14). Results of the meta-analysis revealed a mean effect of physical intervention to reduce intake of -1.003 (95% confidence interval = -1.261 to -0.745, p < 0.001). Results for heterogeneity among these studies were I2 = 67.421; Q = 39.903; df = 13, p < 0.001. The mean energy intake reduction was -323 ± 286 kcal. Macronutrient intake was assessed in 11 interventions. Protein intake was found decreased in five (reduction of -26.8 ± 19.2 g), seven reported fat decrease (reduction of -26.4 ± 17.8 g) and five a decrease in CHO (reduction of -72.5 ± 22.8 g). The meta-analysis revealed significant decreases of each macronutrient (p < 0.001). CONCLUSION: Structured physical activity interventions favour decreased daily energy intake in obese adolescents.

Low socio-economic status is a newly identified independent risk factor for poor vitamin D status in severely obese adults.

BACKGROUND: Hypovitaminosis D is very prevalent, especially in the obese population. However, the degree of severity and the parameters involved in vitamin D deficiency in this population are still unclear. The present study aimed to identify, from among the factors known to influence vitamin D status in a healthy population, those impacting the same parameter in obese population. METHODS: Serum 25-OH-D concentration was measured in 564 patients with class III obesity [i.e. severe and morbid obesity; mean (SD) body mass index (BMI) 42.04 (6.92) kg m-2 ] and their demographic, clinical, biological, anthropometric, dietary and socio-economic data were collected. RESULTS: We observed that 96% of the obese patients had serum 25-OH-D lower than 30 ng mL-1 . Severe vitamin D deficiency (serum 25-OH-D concentration <10 ng mL-1 ) affected 35% of this population. We found an inverse relationship between 25-OH-D levels and BMI (P = 0.012), fat mass (P = 0.041), metabolic syndrome (P < 0.0001), fasting blood glucose (P = 0.023), homeostasis model assessment for insulin resistance (P = 0.008), waist circumference (P = 0.001), and fasting blood triglycerides (P = 0.002) and C-reactive protein (P = 0.005). Low socio-economic status independently increased the risk of severe vitamin D deficiency [odds ratio (OR) = 1.98; 95% confidence interval (CI) 1.25-3.13], especially in the autumn-winter season (OR = 2.94; 95% CI 1.98-4.36), morbid obesity (OR = 3.19; 95% CI 1.49-6.82), metabolic syndrome (OR = 1.6; 95% CI 1.06-2.42) and inflammation (OR = 1.03; 95% CI 1.01-1.06). CONCLUSIONS: Vitamin D deficiency is extremely common among obese patients, and the prevalence of severe deficiency is high. The association of adiposity, high body mass index, metabolic syndrome and inflammation with vitamin D status is marked, whereas low socio-economic status appears to be a major risk factor for severe vitamin D deficiency, suggesting that vitamin D deficiency may at least in part be responsible for the greater health vulnerability of populations with low socio-economic status.

NK cytotoxicity and alloreactivity against neuroblastoma cell lines in vitro: comparison of Europium fluorometry assay and quantification by RT-PCR.

UNLABELLED: New therapies for children with high risk neuroblastoma are needed, and haploidentical stem cell transplantation with NK post-graft injections is a potential option. To develop this strategy, we compared and correlated two methods of NK cytotoxicity assay. The aim of this work is to optimize in vitro NK cytotoxicity assays, investigate the effect of interleukin stimulation on NK cells and use of antiGD2 antibodies against tumor target cells and finally establish an in vitro model for haploidentical stem cell transplantation. EXPERIMENTAL DESIGN: We evaluated NK cell cytotoxicity in vitro against NB cell lines (IMR-32 and SK-NSH) in different culture conditions using a Europium BATDA fluorescence test, and correlated the results with quantification of TH, Phox2B, and DCX transcripts evaluated by RT-PCR. RESULTS: Both IMR-32 and SK-N-SH neuroblastoma cell lines were sensitive to NK cells and particularly when NK cells were stimulated by interleukin IL-2 and IL-15 or when using anti-GD2 antibodies against tumor target cells. All these results were observed either with Europium fluorometry assay or with RT-PCR quantification. There is a clear correlation between the two methods, for the three transcripts at the ratio effector/target 50/1 (TH r=0.75, Phox2B r=0.79 and DCX r=0.8), for all the values whatever the cell line. Besides for all three transcripts, the correlations were significantly independent of the cell line and the ratio E/T (all p values non-significant) even if the best correlation was observed for the ratio 50/1. After prolonged incubation times of effector and target cells (24 h), which could be evaluated only by RT-PCR, all the transcripts clearly decreased, confirming the haploidentical effect of NK against the two neuroblastoma cell lines in our two in vitro haploidentical models but no advantage of mismatch. CONCLUSIONS: NK cytotoxicity against neuroblastoma cell lines can be evaluated by Europium assay and by RT-PCR with clear correlation for the three transcripts TH, Phox2B and DCX whatever the ratio E/T and cell line used. This new method of RT-PCR is simple and suitable for large-scale conditions like study of adherent tumor cells or prolonged incubations of target/effector cells which allowed us to observe haploidentical effect.