Dietary creatine supplementation in gilthead seabream (Sparus aurata): comparative proteomics analysis on fish allergens, muscle quality, and liver

The quality of fish flesh depends on the skeletal muscle's energetic state and delaying energy depletion through diets supplementation could contribute to the preservation of muscle's quality traits and modulation of fish allergens. Food allergies represent a serious public health problem worldwide with fish being one of the top eight more allergenic foods. Parvalbumins, have been identified as the main fish allergen. In this study, we attempted to produce a low allergenic farmed fish with improved muscle quality in controlled artificial conditions by supplementing a commercial fish diet with different creatine percentages. The supplementation of fish diets with specific nutrients, aimed at reducing the expression of parvalbumin, can be considered of higher interest and beneficial in terms of food safety and human health. The effects of these supplemented diets on fish growth, physiological stress, fish muscle status, and parvalbumin modulation were investigated. Data from zootechnical parameters were used to evaluate fish growth, food conversion ratios and hepatosomatic index. Physiological stress responses were assessed by measuring cortisol releases and muscle quality analyzed by rigor mortis and pH. Parvalbumin, creatine, and glycogen concentrations in muscle were also determined. Comparative proteomics was used to look into changes in muscle and liver tissues at protein level. Our results suggest that the supplementation of commercial fish diets with creatine does not affect farmed fish productivity parameters, or either muscle quality. Additionally, the effect of higher concentrations of creatine supplementation revealed a minor influence in fish physiological welfare. Differences at the proteome level were detected among fish fed with different diets. Differential muscle proteins expression was identified as tropomyosins, beta enolase, and creatine kinase among others, whether in liver several proteins involved in the immune system, cellular processes, stress, and inflammation response were modulated. Regarding parvalbumin modulation, the tested creatine percentages added to the commercial diet had also no effect in the expression of this protein. The use of proteomics tools showed to be sensitive to infer about changes of the underlying molecular mechanisms regarding fish responses to external stimulus, providing a holistic and unbiased view on fish allergens and muscle quality.Project Allyfish contract MAR 16-02-01-FMP-0014 (PEP 4107IDNAD50308.12) Mar2020info:eu-repo/semantics/publishedVersio

A potential role for endogenous proteins as sacrificial sunscreens and antioxidants in human tissues

AbstractExcessive ultraviolet radiation (UVR) exposure of the skin is associated with adverse clinical outcomes. Although both exogenous sunscreens and endogenous tissue components (including melanins and tryptophan-derived compounds) reduce UVR penetration, the role of endogenous proteins in absorbing environmental UV wavelengths is poorly defined. Having previously demonstrated that proteins which are rich in UVR-absorbing amino acid residues are readily degraded by broadband UVB-radiation (containing UVA, UVB and UVC wavelengths) here we hypothesised that UV chromophore (Cys, Trp and Tyr) content can predict the susceptibility of structural proteins in skin and the eye to damage by physiologically relevant doses (up to 15.4J/cm2) of solar UVR (95% UVA, 5% UVB). We show that: i) purified suspensions of UV-chromophore-rich fibronectin dimers, fibrillin microfibrils and β- and γ-lens crystallins undergo solar simulated radiation (SSR)-induced aggregation and/or decomposition and ii) exposure to identical doses of SSR has minimal effect on the size or ultrastructure of UV chromophore-poor tropoelastin, collagen I, collagen VI microfibrils and α-crystallin. If UV chromophore content is a factor in determining protein stability in vivo, we would expect that the tissue distribution of Cys, Trp and Tyr-rich proteins would correlate with regional UVR exposure. From bioinformatic analysis of 244 key structural proteins we identified several biochemically distinct, yet UV chromophore-rich, protein families. The majority of these putative UV-absorbing proteins (including the late cornified envelope proteins, keratin associated proteins, elastic fibre-associated components and β- and γ-crystallins) are localised and/or particularly abundant in tissues that are exposed to the highest doses of environmental UVR, specifically the stratum corneum, hair, papillary dermis and lens. We therefore propose that UV chromophore-rich proteins are localised in regions of high UVR exposure as a consequence of an evolutionary pressure to express sacrificial protein sunscreens which reduce UVR penetration and hence mitigate tissue damage

Ecological Meltdown in the Firth of Clyde, Scotland: Two Centuries of Change in a Coastal Marine Ecosystem

BACKGROUND: The Firth of Clyde is a large inlet of the sea that extends over 100 km into Scotland\u27s west coast. METHODS: We compiled detailed fisheries landings data for this area and combined them with historical accounts to build a picture of change due to fishing activity over the last 200 years. FINDINGS: In the early 19th century, prior to the onset of industrial fishing, the Firth of Clyde supported diverse and productive fisheries for species such as herring (Clupea harengus, Clupeidae), cod (Gadus morhua, Gadidae), haddock (Melanogrammus aeglefinus, Gadidae), turbot (Psetta maxima, Scophthalmidae) and flounder (Platichthys flesus, Pleuronectidae). The 19th century saw increased demand for fish, which encouraged more indiscriminate methods of fishing such as bottom trawling. During the 1880s, fish landings began to decline, and upon the recommendation of local fishers and scientists, the Firth of Clyde was closed to large trawling vessels in 1889. This closure remained in place until 1962 when bottom trawling for Norway lobster (Nephrops norvegicus, Nephropidae) was approved in areas more than three nautical miles from the coast. During the 1960s and 1970s, landings of bottomfish increased as trawling intensified. The trawl closure within three nautical miles of the coast was repealed in 1984 under pressure from the industry. Thereafter, bottomfish landings went into terminal decline, with all species collapsing to zero or near zero landings by the early 21st century. Herring fisheries collapsed in the 1970s as more efficient mid-water trawls and fish finders were introduced, while a fishery for mid-water saithe (Pollachius virens, Gadidae) underwent a boom and bust shortly after discovery in the late 1960s. The only commercial fisheries that remain today are for Nephrops and scallops (Pecten maximus, Pectinidae). SIGNIFICANCE: The Firth of Clyde is a marine ecosystem nearing the endpoint of overfishing, a time when no species remain that are capable of sustaining commercial catches. The evidence suggests that trawl closures helped maintain productive fisheries through the mid-20th century, and their reopening precipitated collapse of bottomfish stocks. We argue that continued intensive bottom trawling for Nephrops with fine mesh nets will prevent the recovery of other species. This once diverse and highly productive environment will only be restored if trawl closures or other protected areas are re-introduced. The Firth of Clyde represents at a small scale a process that is occurring ocean-wide today, and its experience serves as a warning to others

City and country in Pisidia from classical antiquity to the middle ages : Ariassos, Sia and their territories

This thesis provides a study of the growth and decline of two small Pisidian urban settlements, Sia and Ariassos, with an especial focus on the relationship, both social and economic, between town and country. The thesis addresses the subject primarily chronologically, although chapter two is diachronic. The first chapter provides an historical and geographical introduction to the subject. The complexities of the ethnic and cultural environment in which the two cities were founded are discussed along with the history of early settlement in the region. The succeeding chapters present, discuss and analyse the archaeological evidence for the growth, transformation and, ultimately, the decline of the settlements. The central argument of the thesis is that the settlements can only be understood if seen both within their local physical and social environment and their larger political environment. The settlements existed as part of a complex urban and rural network. The effects of the changes of the third century AD, the arrival of Christianity, tax reforms and social unrest are all explored. The thesis concludes that the image of uniformity and continuity in this mountainous region can be highly deceptive. During the period in which the Pisidian urban landscape grew, flourished and then disintegrated, the area was subject to an enormous variety of changes, social, political and economic, all of which have to be taken into account when attempting to understand the complexity of the process of urban change.</p

Regionalism in Hellenistic and Roman Asia Minor

La notion de région a depuis fort longtemps été un concept de base de l'analyse historique du monde grec. Cependant, ce concept n'a pas toujours été clairement défini. Les contributions de ce volume n'esquivent pas la question et s'efforcent de mettre en évidence les implications de la notion selon différentes perspectives d'analyse, en prenant pour cadre de référence l'Asie Mineure hellénistique et romaine. Qu'elles examinent la culture, le monnayage ou les institutions politiques, les contributions de ce volume s'attachent à explorer les différentes facettes des identités régionales. De même, elles prennent en considération les moyens par lesquels ces identités pouvaient rester tendanciellement stables ou au contraire évoluer au fil du temps, et définissent leur type d'interaction avec les puissances hégémoniques. Parfois aussi, elles n'hésitent pas à mettre en cause l'utilité de l'approche régionale. Enfin, la question de l'"ethnicité" n'est pas négligée. Ce volume intéressera les spécialistes de l'Asie Mineure, aussi bien que tous ceux qui s'intéressent à la conceptualisation de la notion de région dans le monde méditerranéen.Regions and regionalism have been staples of historical analysis for the Greek world for a very long time. What is meant by a region, however, is not always obvious. The contributions in this volume seek to address the question of defining regions and working out the implications of regionalism along different dimensions of analysis for Asia Minor in the Hellenistic and Roman periods. Looking at culture, coinage, political institutions, the papers explore different markers of regional identity, consider ways in which these identities may remain stable or change over time, review the character of the interaction between regional entities and hegemonic powers, and challenge the usefulness in some cases of regional analysis. Questions of ethnicity are also addressed. This volume will be of interest to historians working in Asia Minor and also to anyone concerned with the conceptual questions around regions and regionalism in the Mediterranean world