Consumption of extra-virgin olive oil rich in phenolic compounds improves metabolic control in patients with type 2 diabetes mellitus: a possible involvement of reduced levels of circulating visfatin.

AIM: Phenolic compounds naturally contained in extra-virgin olive oil (EVOO) have demonstrated anti-inflammatory and antioxidant properties. The present study aimed at evaluating the effects of a polyphenol-rich extra-virgin olive oil (EVOO) (high-polyphenol EVOO, HP-EVOO) on the metabolic control and the production of specific pro-/anti-inflammatory adipokines in overweight patients with type 2 diabetes mellitus (T2D). METHODS: Eleven overweight T2D patients not in treatment with insulin were invited to follow their habitual diet for a total of 8 weeks. During the first 4 weeks (wash-out period), they were asked to consume refined olive oil (ROO, polyphenols not detectable) and then to replace ROO with HP-EVOO (25 mL/day, 577 mg of phenolic compounds/kg) for the remaining 4 weeks. Anthropometric parameters, fasting glycaemia, glycated haemoglobin (HbA1c), high-sensitive C-reactive protein, plasma lipid profile, liver function and serum levels of TNF-α, IL-6, adiponectin, visfatin and apelin were assessed at the end of each 4-week period. RESULTS: HP-EVOO consumption significantly reduced fasting plasma glucose (P = 0.023) and HbA1c (P = 0.039) levels as well as BMI (P = 0.012) and body weight (P = 0.012). HP-EVOO ingestion determined a reduction in serum level of aspartate aminotransferase (AST, P = 0.0056) and alanine aminotransferase (ALT, P = 0.024). Serum visfatin levels strongly decreased after HP-EVOO ingestion (P = 0.0021). CONCLUSIONS: Daily consumption of polyphenol-rich EVOO might improve metabolic control and circulating inflammatory adipokines profile in overweight T2D patients.

Oxidative stress markers: specificity and measurement techniques.

With time, increasing evidence has been obtained of the involvement of oxidative stress in the pathophysiology of several diseases and ageing. Likewise, a large number of epidemiological studies have suggested that some pathologies can be prevented or delayed to some extent by dietary changes such as increased consumption of fruits, grains and vegetables. The above mentioned studies have suggested that the measurement of oxidative stress status, coupled to measurement of antioxidant status, may serve a role in diagnosis and/or treatment. The objective of this paper is to provide a review which, owing to the extent of the available literature, is obviously not exhaustive of current and most recent methods employed for the determination of the most specific markers of DNA, lipid and protein oxidative damage.

Infant feeding in the first year of age: composition and nutritional influence of the diet.

In recent years there has been a remarkable progress in infant nutrition, thanks to important development in the fields of nutrition, and food preparation and storage. The Istituto Superiore di Sanità (Italian National Institute of Health) has carried out the analytical control of the composition of infant foods present on the Italian market, and verified the nutritional quality and the presence, if any, of undesirable substances. Since 1980 the research has often required the development of specific and accurate analytical methods for these products. Adapted and follow-up formulas, cereal-based weaning products and those meant for subjects in special physiological conditions (premature, coeliac, allergic) have been analyzed, monitoring their qualitative transformation during the years. The main essential nutrients-proteins, lipids and minerals-have been assayed to evaluate whether the nutritional requirements of infants during the first year of life were satisfied. The protein and lipid composition of infant formulas was compared with that of human milk, and the influence of such feedings on plasma amino acid levels and erythrocyte fatty acids was assessed.

Protein and lipid composition of human milk and infant formulas: comparison and nutritional consequences.

This work results from some research carried out by the authors during the last few years in nutrition field. The data collected allowed to compare protein and lipid composition of infant formulas with human milk and to evaluate the influence of such feedings on plasma aminoacid levels and erythrocyte fatty acids. In spite of different infant formula compositions with respect to human milk, our nutritional studies did not demonstrate physiological differences between breast and bottle-fed infants if formulas provide with an adequate intake of protein and linoleic acid.

Protein synthesis and amino acid pool during yeast-mycelial transition induced by N-acetyl-D-glucosamine in Candida albicans.

Protein synthesis at different stages of yeast-mycelial transition induced by N-acetyl-D-glucosamine in Candida albicans was evaluated by following incorporation of radioactive amino acids into the acid-insoluble cellular material. In passing from the early germ-tube formation (60-90 min) to the mature hyphal cell (240-270 min) there was a marked decrease in the capacity for protein synthesis. Apparently, this decrease was not due to a decreased amino acid uptake into the soluble cellular pool or to exhaustion of carbon/energy source in the inducing medium with consequent arrest of growth. Protein synthesis, however, did not decay when amino acids at high concentration were added to the medium fostering the yeast-mycelial transition and this effect was potentiated by glucose. Analysis of the intracellular amino acid pool showed that both germ-tubes and hyphal cells were relatively depleted of several amino acids as compared to the yeast-form cells, whereas in the hyphae there was a higher concentration of glutamic acid/glutamine, the latter being the predominant component. These modulations in amino acid pool composition were not seen when yeasts were converted to hyphae in an amino acid-rich induction medium. This study emphasizes that yeast-form cells of C. albicans may efficiently convert to the mycelial form even under a progressively lowered rate of protein synthesis, and suggests that initiation of hyphal morphogenesis in the presence of N-acetyl-D-glucosamine is somehow separated from cellular growth.