Influence of early-life and parental factors on childhood overweight and obesity

PURPOSE

We recently reported that a high BMI and high waist circumference prevalence is present in Sicilian children and that the male gender is associated with a significant risk of obesity. Early-life and parent-related risk factors were investigated 1521 Sicilian children (752 females and 769 males, aged 9.0-14.0 years) to identify biological and environmental factors that can contribute to obesity onset.

METHODS

Anthropometric measurements of children, their urban vs rural area provenience, birth weight and neonatal feeding were collected. In addition, the BMI and educational level of their parents and the perception of their child weight status were investigated.

RESULTS

In the study cohort, the prevalence of overweight and obesity was 27.2 and 14.1 %, respectively, significantly (p < 0.05) higher in males than in females. Breastfeeding emerged as a protective factor (OR 0.64; p < 0.0005), while risk factors for developing childhood obesity were a birth weight ≥4.0 kg (OR 1.83; p < 0.05), an overweight or obese mother (OR 2.33; p < 0.0001) or father (OR 1.68; p < 0.0001) and a mother with a low/medium education level (OR 1.72; p < 0.005).

CONCLUSION

Understanding risk factors for pediatric obesity is a prerequisite to identify children at highly risk of being obese and to predispose early intervention strategies.

Role of cytosolic and calcium independent phospholipases A(2) in insulin secretion impairment of INS-1E cells infected by S. aureus

Cytosolic PLA2 (cPLA2) and Ca(2+)-independent PLA2 (iPLA2) play a significant role in insulin β-cells secretion. Bacterial infections may be responsible of the onset of diabetes. The mechanism by which Staphylococcus aureus infection of INS-1 cells alters glucose-induced insulin secretion has been examined. After acute infection, insulin secretion and PLA2 activities significantly increased. Moreover, increased expressions of phospho-cPLA2, phospho-PKCα and phospho-ERK 1/2 were observed. Chronic infection causes a decrease in insulin release and a significant increase of iPLA2 and COX-2 protein expression. Moreover, insulin secretion in infected cells could be restored using specific siRNAs against iPLA2 isoform and specific COX-2 inhibitor.

Adiponectin increases glucose-induced insulin secretion through the activation of lipid oxidation

The expression of adiponectin receptors has been demonstrated in human and rat pancreatic beta cells, where globular (g) adiponectin rescues rat beta cells from cytokine and fatty acid-induced apoptosis. The aim of our study was to evaluate whether adiponectin has a direct effect on insulin secretion and the metabolic pathways involved. Purified human pancreatic islets and rat beta cells (INS-1E) were exposed (1 h) to g-adiponectin, and glucose-induced insulin secretion was measured. A significant increase in glucose-induced insulin secretion was observed in the presence of g-adiponectin (1 nmol/l) with respect to control cells in both human pancreatic islets (n = 5, p < 0.05) and INS-1E cells (n = 5, p < 0.001). The effect of globular adiponectin on insulin secretion was independent of AMP-dependent protein kinase (AMPK) activation or glucose oxidation. In contrast, g-adiponectin significantly increased oleate oxidation (n = 5, p < 0.05), and the effect of g-adiponectin (p < 0.001) on insulin secretion by INS-1E was significantly reduced in the presence of etomoxir (1 μmol/l), an inhibitor of fatty acid beta oxidation. g-Adiponectin potentiates glucose-induced insulin secretion in both human pancreatic islets and rat beta cells via an AMPK independent pathway. Increased fatty acid oxidation rather than augmented glucose oxidation is the mechanism responsible. Overall, our data indicate that, in addition to its anti-apoptotic action, g-adiponectin has another direct effect on beta cells by potentiating insulin secretion. Adiponectin, therefore, in addition to its well-known effect on insulin sensitivity, has important effects at the pancreatic level.

Effect of the intravenous anesthetic 2,6-diisopropylphenol on respiration and energy production by rat brain synaptosomes

The sensitivity of the mitochondrial energy production system to propofol (DPP) has been investigated in rat brain synaptosomes. DPP at 0.8 mM concentration produced a partial inhibition of coupled respiration, an apparent decrease of the oxygen uptake stimulation induced by CCCP and a full inhibition of the mitochondrial ATP production by synaptosomes. Higher concentrations of DPP (1 mM) fully abolish uncoupler-dependent stimulation and at 1.3 mM DPP also coupled respiration is completely blocked. Similar results were obtained when dinitrophenol replaced CCCP and phenol or propylbenzene replaced DPP. The presence of the alkyl residues seems critical for the DPP effect. In the presence of 30 mM glutamate both respiration and ATP production are enhanced but DPP effects are similar to those obtained in the absence of glutamate.