Effect of dietary thymol supplementation on lipid oxidation of chicken legs as related to storage conditions

The aim of this research was to evaluate the effect of dietary thymol supplementation on lipid oxidation of chicken leg meat during refrigerated shelf-life. Chickens belonging to Ross 308 hybrid were raised under experimental conditions up to 3 kg of live weight, using three dietary treatments: control (without supplementation, C), treatment 1 (C+0.1% w/w thymol supplementation, T1) and treatment 2 (C+0.2% w/w thymol supplementation, T2). After slaughtering, the chicken legs with skin were stored under conventional (CON) and modified atmosphere (MAP) at temperature of 2-4°C for 14 days. Lipid oxidation was monitored by the determination of primary (peroxide value, PV) and secondary (thiobarbituric acid reactive substances, TBARs) products at 3, 7, 10 and 14 days of storage under both CON and MAP conditions and compared with values found on fresh meat. The three different dietary treatments did not significantly affect the lipid oxidation parameters. PV ranged between 0.5-13.0, 0.7-13.0 and 1.0-11.0 meq O2/kg of lipid in poultry meat obtained with C, T1 and T2 diets, respectively. TBARs varied between 0.1-0.7, 0.1- 0.6 and 0.2-0.5 mg MDA/kg of meat in poultry meat obtained with C, T1 and T2 diets, respectively. On the other hand, interaction effect of diets and storage conditions were significant (P≤0.05) in PV formation, as it was delayed under MAP (maximum PV level after 2 and 5 days of storage in C and thymol-containing diets, respectively) with respect to conventional storage (PV apex after 2 days of storage). However, not significant differences (P≥0.05) were found on TBARs level as related to storage conditions. In conclusion, this study demonstrated that dietary thymol supplementation coupled to MAP storage conditions delay lipid oxidation of chicken legs with skin, thus improving their shelf-life

Genome-wide expression profiling and functional characterization of SCA28 lymphoblastoid cell lines reveal impairment in cell growth and activation of apoptotic pathways

BACKGROUND: SCA28 is an autosomal dominant ataxia associated with AFG3L2 gene mutations. We performed a whole genome expression profiling using lymphoblastoid cell lines (LCLs) from four SCA28 patients and six unrelated healthy controls matched for sex and age. METHODS: Gene expression was evaluated with the Affymetrix GeneChip Human Genome U133A 2.0 Arrays and data were validated by real-time PCR. RESULTS: We found 66 genes whose expression was statistically different in SCA28 LCLs, 35 of which were up-regulated and 31 down-regulated. The differentially expressed genes were clustered in five functional categories: (1) regulation of cell proliferation; (2) regulation of programmed cell death; (3) response to oxidative stress; (4) cell adhesion, and (5) chemical homeostasis. To validate these data, we performed functional experiments that proved an impaired SCA28 LCLs growth compared to controls (p\u2009<\u20090.005), an increased number of cells in the G0/G1 phase (p\u2009<\u20090.001), and an increased mortality because of apoptosis (p\u2009<\u20090.05). We also showed that respiratory chain activity and reactive oxygen species levels was not altered, although lipid peroxidation in SCA28 LCLs was increased in basal conditions (p\u2009<\u20090.05). We did not detect mitochondrial DNA large deletions. An increase of TFAM, a crucial protein for mtDNA maintenance, and of DRP1, a key regulator of mitochondrial dynamic mechanism, suggested an alteration of fission/fusion pathways. CONCLUSIONS: Whole genome expression profiling, performed on SCA28 LCLs, allowed us to identify five altered functional categories that characterize the SCA28 LCLs phenotype, the first reported in human cells to our knowledge. \ua9 2013 Mancini et al.; licensee BioMed Central Ltd

Influenza dei fattori e delle metodologie di allevamento sulle caratteristiche qualitative e sulla stabilità dei prodotti di origine animale

Nowadays it is requested more investigations on alternative rearing systems that are able to improve poultry welfare and to warrant high-quality and safe meat products. This thesis work was focused on the evaluation of the oxidative stability of poultry meats, obtained with different rearing systems, diets (supplemented with bioactive compounds), and packaging conditions. The thesis work was divided into the following parts: - Evaluation of the effects of different rearing systems on the quality, fatty acid composition and oxidative stability of poultry thigh and breast meat belonging to different product categories (“rotisserie” and “cut-up” carcasses); - Evaluation of the effects of different rearing systems and packaging conditions on the shelf-life of poultry thigh meat stored at 4°C for 14 days, and the effects of feed supplementation with thymol (control diet and diet with 2 different concentration of thymol) and packaging conditions on lipid oxidation of poultry thigh meat shelf-life (stored at 4°C for 14 days). The oxidative stability of poultry meat was studied by means of the spectrophotometric determinations of peroxide value and thiobarbituric acid reactive substances. - Evaluation of anti-inflammatory effects of different flavonoids (thymol, luteolin, tangeretin, sulforaphane, polymethoxyflavones, curcumin derivates) to detect their biological activity in LPS-stimulated RAW 264.7 macrophage cells in vitro, in order to study more in depth their action mechanisms. It was evaluated the cell vitality (MTT assay), nitrite concentration and protein profile. The study was focused on the identification of potential dietary bioactive compounds in order to investigate their biological activity and possible synergic effects, and to develop new suitable strategies for long-term promotion of human health, in particular against cancer.Oggigiorno sono sempre più richiesti i lavori di ricerca sullo studio di sistemi di allevamento alternativi in grado di migliorare il benessere degli animali e di migliorare la qualità e la sicurezza delle carni. Il presente elaborato di tesi si è basato sulla valutazione dello stato ossidativo di carni avicole, provenienti da animali allevati con sistemi alternativi ed alimentati con diete integrate con composti bioattivi, e conservate in diverse tipologie di packaging. L’organizzazione della ricerca si è sviluppata nei seguenti punti: - Valutazione dell’effetto di sistemi di allevamento alternativi del pollo da carne sulla qualità, composizione degli acidi grassi e stabilità ossidativa della frazione lipidica muscolare delle carni di petto e coscia ottenute da due categorie commerciali (“Rotisserie” e “Cut-up”); - Studio della stabilità ossidativa condotta mediante prove di shelf-life su carni di coscia ottenute da polli allevati con diversi sistemi di allevamento e alimentati con tre tipi di diete (dieta di controllo e diete arricchite di timolo a due diverse concentrazioni). Queste carni sono state confezionate con diverse modalità (atmosfera ordinaria e protettiva) e conservate in condizioni di refrigerazione (2-4°C) per 14 giorni. La stabilità ossidativa è stata valutata mediante le determinazioni spettrofotometriche del numero di perossidi e delle sostanze reattive all’acido tiobarbiturico; - Valutazione dell’attività anti-infiammatoria di diversi bioflavonoidi (timolo, luteolina, tangeretina, sulforafano, polimetossiflavoni, derivati della curcumina), facendo luce sui meccanismi d’azione di quest’ultimi, su linee cellulari macrofagiche (LPS-stimulated RAW 264.7 cells) in vitro. Sono stati valutati la vitalità cellulare (MTT assay), la determinazione indiretta dell’ossido nitrico e l’identificazione delle proteine. In particolare, il lavoro si è soffermato sull’identificazione di potenziali componenti nutraceutici, caratterizzati da una forte azione sinergica, con lo scopo di indagare sulla loro attività biologica ed i loro possibili effetti sinergici e quindi di sviluppare nuove strategie finalizzate alla prevenzione del cancro, a lungo termine