PGC-1-related coactivator (PRC) was initially characterized as a transcriptional coactivator that shares structural and functional features with PGC-1␣. Both coactivators interact with nuclear respiratory factor 1 (NRF-1) and activate NRF-1 target genes required for respiratory chain expression. Here, we establish that PRC belongs to the class of immediate early genes that are rapidly induced in the transition from quiescence to proliferative growth. As observed for other members of this class, the rapid serum induction of PRC mRNA does not require de novo protein synthesis and inhibition of protein synthesis stabilizes PRC mRNA, leading to its superinduction. Previous work indicated that PRC activation of cytochrome c expression occurs through cis-acting elements that bind both NRF-1 and CREB. Here, we demonstrate that, like NRF-1, CREB binds PRC in vitro and exists in a complex with PRC in cell extracts. Both CREB and NRF-1 bind the same sites on PRC, and the interaction with CREB requires the CREB b-Zip DNA binding domain. Moreover, a CREB/NRF-1 interaction domain on PRC is required for its trans activation of the cytochrome c promoter and a PRC subfragment containing this domain inhibits respiratory growth on galactose when expressed in trans from a lentivirus vector. Finally, PRC associates with the cytochrome c promoter in vivo and its occupancy of the promoter is markedly elevated in response to serum induction of quiescent fibroblasts. The results establish that PRC is an immediate early gene product that can target key transcription factors as an early event in the program of cellular proliferation.Mitochondrial biogenesis relies upon the integrated expression of both the nucleo-cytosolic and the mitochondrial genetic system (7). Although mitochondria have their own DNA (mtDNA), which, in vertebrates, is a covalently closed circular molecule of approximately 16.5 kilobases, the protein coding capacity of this genome is limited to 13 polypeptide subunits of respiratory chain complexes I, III, IV, and V. The only other products of mtDNA expression are the tRNAs and rRNAs of the mitochondrial translation system. This arrangement necessitates that nuclear genes encode the majority of respiratory chain subunits as well as all of the gene products required for the transcription and replication of mtDNA.In recent years, there have been significant inroads into understanding the transcriptional mechanisms that contribute to nucleo-mitochondrial interactions in mammalian systems (15). Key components of the mitochondrial transcriptional machinery have been characterized (8). These include a single mitochondrial RNA polymerase (POLRMT); a stimulatory factor (Tfam), which binds DNA and is required for maintenance of the mitochondrial genome; specificity factors (TFB1M and -2M) that interact with Tfam and the polymerase; and a termination factor (mTERF), which may help regulate the rRNA/mRNA ratio. In addition, several nuclear transcription factors that act on nuclear genes required for mitochondrial function have b...

It has been shown that several factors such as feed source and breed might influence milk fat-soluble antioxidants (AOs). This study investigated pasture feeding effects and dairy cattle breed on the content of α-tocopherol and β-carotene in cows' milk by monitoring two grazing seasons (spring and fall) as well as a summer nopasture season. Four dairy farms located in Sicily were selected: two with both Holstein and Brown Swiss cows and two with only a Modicana (M) local breed cows. Bulk milk samples of each breed per farm were collected. Milk α-tocopherol and β-carotene were highest during spring (16.2 and 9.7 μg.g −1 of fat, respectively), lowest during fall (11.2 and 0.8 μg.g −1 of fat, respectively) and intermediate during summer (13.3 and 2.5 μg.g −1 of fat, respectively). These results indicate that grazing pasture season has an important impact on milk fat-soluble antioxidant content. In particular, higher milk AO levels in spring compared to fall might be attributed to several factors such as differences in the quality and composition of pasture, differences in pasture intake and even the climate. Breed effect on milk AO contents was not so pronounced. Milk β-carotene levels did not differ significantly among breeds. Saturation of milk β-carotene may explain similar vitamin levels among breeds in spring despite different pasture intakes. It was interesting that significant levels of αtocopherol were detected in milk from M cows during summer. The latter effect could be masked by the considerably higher pasture intake of M in spring compared to the other two breeds.

-Polyunsaturated fatty acids and lipo-soluble vitamins in the milk are considered as neutraceutical compounds due to their beneficial effects on human health. The aim of the present study was to evaluate the changes in fatty acid composition and fat-soluble antioxidant content in plasma and milk from cows fed with different dietary proportions from pasture. Cows from a farm in the Hyblean mountain region in Italy were randomly divided into three groups (12 animals per group): CTRL fed only a total mix ration (TMR); 30P fed a TMR supplemented with 30% dry matter (DM) from pasture and 70P fed a TMR supplemented with 70% DM of pasture. Blood and milk samples were collected, stored and analysed for their content of fatty acids and fat-soluble antioxidants. Fatty acid profiles were significantly modified by different diets. CLA, vaccenic acid (VA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) significantly (P < 0.05) increased in plasma as a function of the proportion of pasture added to the diet. In agreement with these data, a progressively significant (P < 0.05) increase in concentrations of VA, CLA and EPA was observed in the milk. Such changes in fatty acid composition were accompanied by a concomitant increase in the concentrations of α-tocopherol and β-carotene in both plasma and milk. The increase in EPA, DHA and CLA, β-carotene and α-tocopherol in plasma may not only have a beneficial impact for milk and meat quality, but may also result in an increased protection against inflammatory events. Article published by EDP SciencesRésumé -L'augmentation de la teneur en herbe de la ration améliore la teneur en acides gras polyinsaturés et en antioxydants lipophiles dans le plasma et le lait des vaches laitières en ration complète. Les acides gras polyinsaturés (AGPI) et les vitamines liposolubles du lait sont considérés comme des composés nutraceutiques en raison de leurs effets bénéfiques pour la santé. Le but de cette étude était d'évaluer les changements de composition en acides gras et de teneur en antioxydants liposolubles dans le plasma et le lait de vaches laitières recevant différentes proportions de pâture. Les vaches provenant d'une ferme de la région du mont Iblei en Italie, ont été réparties aléatoirement en trois groupes (12 animaux par groupe) : un groupe témoin recevant une alimentation en ration complète (TMR) ; un groupe recevant une alimentation TMR supplémentée à hauteur de 30 % de matière sèche en herbe ; un groupe recevant une alimentation TMR supplé-mentée à hauteur de 70 % de matière sèche en herbe. Des échantillons sanguins et du lait ont été collectés, conservés et analysés pour leur teneur en acides gras et en antioxydants liposolubles. Les profils en acides gras étaient modifiés de façon significative par les différents régimes. L'acide linoléique conjugué (CLA), l'acide vaccénique (VA), l'acide eisapentanoïque (EPA) et l'acide docohexanoïque (DHA) augmentaient significativement (P < 0,05) dans le plasma en fonction de la proportion de pâture. En accord avec ces rés...

The opportunity of replacing expensive feedstuffs with agro-industrial by-products in the diet of food producing animals is raising increasing interest while addressing global concern for the scarcity of natural resources and environmental impact of livestock farming. Hazelnut peels, rich in fiber and vitamins and characterized by a high concentration of fats, is considered a suitable ingredient to be included in the diet of ruminants. The aim of this research was to assess the effect of dietary hazelnut peels on the chemical and sensory properties of sheep cheese during refrigerated storage. To this purpose, 20 Comisana lactating ewes were randomly assigned to two experimental groups, control (C) and hazelnut peels (HP), balanced for parity, milk yield and body weight. Bulk milk collected from the 2 groups was used to produce 5 Pecorino cheeses for each group. After 40 d of aging, each cheese of each experimental group was divided into 3 pieces: 1 piece was sampled for analyses (C0, HP0) and 2 were wrapped in PVC film, simulating the condition of pre-wrapped products, and analyzed after 7 (C7, HP7) and 14 days of storage (C14, HP14) at 8°C with 80% moisture. The cheeses were analyzed for chemical and fatty acid composition, sensory analysis, odor active compounds and SmartNose. As expected, HP cheeses presented a higher lipid content compared to C, a lower content in SFA and PUFA, and a greater content in MUFA. A triangle test revealed a clear distinction between the 2 groups (α = 0.01) The sensory profile showed a significant effect on holes ( P < 0.05) and a marginal production of off-flavors linked to spicy and acid attributes for HP cheeses The volatile profile of C and HP cheese samples showed a good similarity, partially explained by the short ripening time and the absence of 2-nonanone in HP7, suggesting a higher antioxidant protection grade of this cheese compared to the others. These results were confirmed by Smart Nose analysis. Further studies on vitamin content should be conducted in order to investigate the interactions between the presence of antioxidant volatile compounds and the oxidative stability of ewe cheese.

This study was performed to evaluate α-tocopherol and β-carotene contents of pasture milk under ordinary Sicilian farming conditions. Fourteen dairy farms were allocated into 2 balanced groups on the basis of cultivated (CULT) or spontaneous (SPO) pasture type feeding. Bulk milk per farm was collected 4 times from February through April at 3-wk intervals. Pasture botanical and diet composition, diet nutritional quality, milk yield and composition were estimated each time. Pasture intake levels were calculated based on feed analyses, hay and concentrate amounts fed, and milk yield and chemical composition. According to pasture intake, the farms were split into low pasture intake (LPI; <29.5% of dry matter) and high pasture intake (HPI; >29.5% of dry matter) groups. Milk samples per farm were analyzed for α-tocopherol and β-carotene contents by HPLC. The SPO group had higher levels of α-tocopherol and β-carotene in milk (0.7 and 0.3 mg/L, respectively) and milk fat (19.0 and 7.5 mg/kg fat, respectively) compared with the CULT group in milk (0.5 and 0.2 mg/L, respectively) and milk fat (14.6 and 4.9 mg/kg, respectively). High pasture intake compared with LPI increased α-tocopherol in milk fat (18.0 and 16.0 mg/kg of fat, respectively). However, only in the SPO (not in CULT), HPI compared with LPI increased milk α-tocopherol (0.8 vs. 0.6 mg/L, respectively), milk β-carotene (0.3 vs. 0.2 mg/L, respectively), and milk fat β-carotene (8.4 vs. 6.6 mg/kg, respectively). Results may be related to the different botanical composition of the respective pasture types and pasture intake. Spontaneous pasture compared with CULT contained a higher mass proportion of Asteraceae, Fabaceae, Cruciferae, Euphorbiaceae, and Malvaceae plants. Milk and milk fat α-tocopherol levels were higher on test-days (TD)-1, TD-2, and TD-4 compared with TD-3. For HPI farms, milk fat β-carotene content was higher on the first 2 TD compared with the last 2 TD. These differences could be related to plant biological stage. On Sicilian dairy farms, the highest milk α-tocopherol and β-carotene contents may be obtained feeding high levels of SPO pasture in the spring.