by Chiu Shui-fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 186-203.

Sea bass (Lateolabrax maculatus) has been used for dietary therapy practice in China. In traditional Chinese medicinal books, it has been indicated that sea bass can be applied for managing many inflammation associated conditions. However, the studies on the pharmacological mechanisms of anti-inflammation of sea bass remain scarce. Hence, this study aims to illustrate the pharmacological and chemical basis for the folk use of sea bass in managing inflammation- associated conditions. For in vivo studies, dietary effect of sea bass on inflammation-associated conditions in ulcerative colitis, skin wounds, and intestinal dysbiosis were evaluated. A series of inflammatory mediators associated with wound healing and ulcerative colitis, and the proliferation effects of fibroblasts upon treatments were studied via Western blotting, enzyme-linked immunosorbent assay (ELISA), hematological parameters, histopathological and Immunofluorescence analysis, using cutaneous wound model and DSS induced colitis model, respectively. β-diversity analysis and species variance statistics were conducted to evaluate the effect of ASB on the microbial communities with colitis and discovered the high dimensional biomarkers. Results showed that ASB could significantly ameliorate several pathophysiological and morphological features in DSS induced colitis. ASB has a potential in accelerating the proliferation phase of wound healing via well-organized abundant collagen deposition, angiogenesis, strengthening the skin contraction and skin organ maturation in wounds. Moreover, the study also found that ASB could significantly down-regulated the expression levels of inflammatory associated mediators in colitis and skin wound. Additionally, principal coordinate analysis (PCoA) and relative abundance at phylum level among groups were indicated that ASB possess a potential amelioration on intestinal dysbiosis in colitis. Histogram of linear discriminant analysis (LDA) scores and Cladogram as the results of LEfSe analysis identified that Christensenellaceae might be treated as the the biomarker for treating colitis. For in vivo studies, macrophages and fibroblasts were used for further evaluation. Result showed that ASB could significantly inhibited the production of pro-inflammatory mediators in lipopolysaccharide (LPS) induced macrophages. The mRNA and protein expression level of inflammatory associated mediators were significantly down-regulated upon ASB treatment. Moreover, results also suggested that ASB treatment has a closely link to accelerate the wound healing through migration and proliferation enhancement. Furthermore, the characterization of the aqueous extract of sea bass (ASB) was conducted. Six kinds of peptides and two protein identified from fraction F1 by LC-QE-HF-MS might be responsible for anti-inflammatory activity. It confirmed that Fraction F1 could be treated as the main component for contributing the potential anti-inflammatory activities to ASB. Current results illustrated that fraction F1 (kDa) is a kind of nanoparticles with stability separated from ASB. It can be treated as a promising candidate for treating inflammation associated conditions, providing the chemical basis for the folk use of sea bass in managing inflammation-associated conditions. Current studies established a pharmacological and chemical basis for the folk use of sea bass in managing inflammation-associated conditions. A further justification for the clinical application of sea bass in treating inflammation associated conditions is necessary. Keywords: sea bass; inflammation; ulcerative colitis; wound healing; gut microbiota; peptides

Aquaculture is an essential developing sector for world food production however one of the major bottlenecks for the sustainability of the aquaculture industry is the ability to control fish reproduction in captivity and to produce high quality seeds. European sea bass is a one of most commercially important species for the European fish farming industry. If broodstock management under captivity is well established, problems remain in hatcheries where survival can be low and deformity prevalence high as well as in on growing sites where fish reach puberty early especially with skewed sex ratio towards males. Sea bass displays strong seasonality in its physiology and is therefore an excellent candidate for the study of the photo-neuroendocrine control of reproduction and growth. The overall aims of this thesis were to better understand the molecular and endocrine drivers that control the Brain-Pituitary-Gonad axis in repeat spawner sea bass, and expand our knowledge of sea bass light and temperature regulation of melatonin production. First, this PhD project investigated the seasonal expression of kisspeptin, GnRH and gonadotropin genes in relation to the gonadal development throughout a reproductive cycle in male repeat spawning sea bass (Chapter 3). A partial sequence for the receptor kissr4 was isolated and described showing similarity to all other teleost species sequences available to date. QPCR molecular assays were validated to mesure the expression of a suite of genes along the BPG axis including kisspeptin related genes (Kiss1 and Kiss2 and its receptor kissr4) over a full reproductive cycle (12 months) in adult male European sea bass. Brain Kisspeptin mRNA expression levels (kiss1, 2 and kissr4) showed clear seasonal profiles and correlated well to other BPG markers (GnRHs, fshβ and lhβ), supporting a possible involvement of kisspeptin genes in the seasonal control of reproduction in repeat spawning sea bass. Moreover, clear seasonal patterns were observed for expression of the genes encoding for pituitary mRNA expression of lhβ and fshβ, with a significant correlation between expression of both subunits and GSI and steroids levels. However, no clear seasonal profiles in brain GnRHs gene expression were observed with the exception to some peaks in GnRH1 and GnRH2. The second part of this PhD project investigated the potential direct effect of the two kisspeptin core peptides (kiss1 and kiss2) on the pituitary gonadotropin gene expression (Chapter 4). The aim of this work was to better understand the mechanism by which kisspeptin acts on the BPG axis. This was done by testing the kisspeptin decapeptide core sequences on the lhβ and fshβ transcript expression in primary culture of sea bass pituitary cells using QPCR technique. The findings, as a whole, provided evidence that kisspeptin can act directly on the pituitary gonadotroph cells and modulate fshß and lhß mRNA expression in sea bass although effects were limited and not uniform. Of note, kissr4 gene expression was also detected in the sea bass pituitary. The third part of this PhD project focused on the effects of environmental signals (photoperiod and temperature) on melatonin production (Chapter 5). Environmental manipulation is routinely used in the aquaculture industry with the purpose of enhancing growth and manipulating the timing of reproduction in seasonal fish species like sea bass. Melatonin, known as the light perception and time keeping hormone, has been suggested to play key roles in the synchronisation of most physiological functions in vertebrates, although the mechanisms by which melatonin controls reproduction, growth and behaviour are still not fully understood in fish. The studies performed aimed .to determine the synergistic effects of both temperature and photoperiod on the daily phase and amplitudinal changes in melatonin production through both in vivo and in vitro trials. The results confirmed the diel melatonin rhythm in sea bass as previously reported in many teleost species with “high at night” and “low at day” melatonin profiles. Temperature showed clear effects on the amplitude of the melatonin production under both in vivo and in vitro conditions for both long day and short day photoperiods. Furthermore, no endogenous melatonin production was found under constant darkness in both in vivo and in vitro conditions. These results suggested a lack of intrapineal (or located elsewhere such as retina and/or deep brain) oscillators in sea bass, contrasting with previous reports. These results further enhance our knowledge of light perception and circadian rhythmicity in sea bass, while the circadian system remains to be characterised in sea bass and teleosts as a whole. Overall, this doctoral work broadened our understanding on the photoneuroendocrine control of reproduction in a seasonal fish species, sea bass. New knowledge gained and tools developed from this work should help to develop/optimise husbandry techniques for the sea bass farming industry with the view to increase production and profitability and thus promoting the sustainable expansion of the sea bass aquaculture in Europe. It has also the potential to help the fishery sector in the modelling of wild sea bass populations.

Os objetivos deste estudo foram descrever a composição taxonômica e distribuição horizontal das larvas de Serranidae na Plataforma Continental Sudeste Brasileira (PCSE), e verificar a interferência dos fatores ambientais e bióticos na distribuição larval. O material provém de 10 cruzeiros oceanográficos realizados nos meses de janeiro, maio, setembro e dezembro de 1975 a 1981, entre cabo Frio (RJ) e cabo de Santa Marta Grande (SC) e depositados na \"Coleção Biológica Prof. E. F. Nonato\". As larvas de Serranidae (933) foram identificadas em 14 táxons (Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus itajara, Epinephelus morio, Epinephelus nigritus, Epinephelus tipo 1, Epinephelus spp., Mycteroperca spp., Pseudogramma gregoryi, Rypticus spp., Anthias menezesi, Hemanthias vivanus, Pronotogrammus martinicensis), distribuídos em nove gêneros e três subfamílias (Serraninae, Anthiinae, Epinephelinae). Com exceção de D. formosum, que apresentou ampla distribuição na plataforma interna da PCSE, e Epinephelus tipo 1 e Hemanthias vivanus, que se distribuíram preferencialmente na região sul da PCSE, os demais táxons se distribuíram na região norte da PCSE (cabo Frio-RJ a São Sebastião-SP), não ultrapassando a isóbata de 200 m. Os fatores salinidade, distância das ilhas e latitude foram significativos na distribuição de Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus tipo 1, e Mycteroperca spp., táxons mais abundantes. Foi obtido um avanço na identificação de Epinephelus (E. morio, E. itajara e E. nigritus) e ratificada a morfologia dos espinhos alongados de E. nigritus. / This study describes the taxonomic composition and horizontal distribution of Serranidae larvae along Southeastern Brazilian Continental Shelf (SBSC), and investigates how environmental and biological factors influence the larval distribuction. The samplers, deposited in the Marine Biological Collection \"Prof. E. F. Nonato\", were collected on the 10 survey cruisers conducted on january, may, september and december from 1975 to 1981, between cape Frio (RJ) to cape Santa Marta Grande (SC). Larvae of Serranidae (933) were identified into 14 taxa (Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus itajara, Epinephelus morio, Epinephelus nigritus, Epinephelus tipo 1, Epinephelus spp., Mycteroperca spp., Pseudogramma gregoryi, Rypticus spp., Anthias menezesi, Hemanthias vivanus, Pronotogrammus martinicensis), included in nine genera and three subfamilies (Serraninae, Anthiinae and Epinephelinae). Except for Diplectrum formosum, that was widely distributed throughout the southeastern continental shelf, and Epinephelus type 1 and Hemanthias vivanus, that were distributed into the south portion of the SBSC, other taxa distributed into the north portion of the SBSC (from cape Frio to São Sebastião), not exceeding the 200 m isobath. The salinity, latitude and distance of islands were significant factors in the horizontal distribution of Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus type 1 and Mycteroperca spp., most abundant taxa. A significant progress was considered in identifying grouper larvae (Epinephelus morio, Epinephelus itajara and Epinephelus nigritus) and ratified the morphology of the elongated spines of E. nigritus.

Os objetivos deste estudo foram descrever a composição taxonômica e distribuição horizontal das larvas de Serranidae na Plataforma Continental Sudeste Brasileira (PCSE), e verificar a interferência dos fatores ambientais e bióticos na distribuição larval. O material provém de 10 cruzeiros oceanográficos realizados nos meses de janeiro, maio, setembro e dezembro de 1975 a 1981, entre cabo Frio (RJ) e cabo de Santa Marta Grande (SC) e depositados na \"Coleção Biológica Prof. E. F. Nonato\". As larvas de Serranidae (933) foram identificadas em 14 táxons (Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus itajara, Epinephelus morio, Epinephelus nigritus, Epinephelus tipo 1, Epinephelus spp., Mycteroperca spp., Pseudogramma gregoryi, Rypticus spp., Anthias menezesi, Hemanthias vivanus, Pronotogrammus martinicensis), distribuídos em nove gêneros e três subfamílias (Serraninae, Anthiinae, Epinephelinae). Com exceção de D. formosum, que apresentou ampla distribuição na plataforma interna da PCSE, e Epinephelus tipo 1 e Hemanthias vivanus, que se distribuíram preferencialmente na região sul da PCSE, os demais táxons se distribuíram na região norte da PCSE (cabo Frio-RJ a São Sebastião-SP), não ultrapassando a isóbata de 200 m. Os fatores salinidade, distância das ilhas e latitude foram significativos na distribuição de Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus tipo 1, e Mycteroperca spp., táxons mais abundantes. Foi obtido um avanço na identificação de Epinephelus (E. morio, E. itajara e E. nigritus) e ratificada a morfologia dos espinhos alongados de E. nigritus. / This study describes the taxonomic composition and horizontal distribution of Serranidae larvae along Southeastern Brazilian Continental Shelf (SBSC), and investigates how environmental and biological factors influence the larval distribuction. The samplers, deposited in the Marine Biological Collection \"Prof. E. F. Nonato\", were collected on the 10 survey cruisers conducted on january, may, september and december from 1975 to 1981, between cape Frio (RJ) to cape Santa Marta Grande (SC). Larvae of Serranidae (933) were identified into 14 taxa (Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus itajara, Epinephelus morio, Epinephelus nigritus, Epinephelus tipo 1, Epinephelus spp., Mycteroperca spp., Pseudogramma gregoryi, Rypticus spp., Anthias menezesi, Hemanthias vivanus, Pronotogrammus martinicensis), included in nine genera and three subfamilies (Serraninae, Anthiinae and Epinephelinae). Except for Diplectrum formosum, that was widely distributed throughout the southeastern continental shelf, and Epinephelus type 1 and Hemanthias vivanus, that were distributed into the south portion of the SBSC, other taxa distributed into the north portion of the SBSC (from cape Frio to São Sebastião), not exceeding the 200 m isobath. The salinity, latitude and distance of islands were significant factors in the horizontal distribution of Diplectrum formosum, Diplectrum spp., Serranus spp., Epinephelus type 1 and Mycteroperca spp., most abundant taxa. A significant progress was considered in identifying grouper larvae (Epinephelus morio, Epinephelus itajara and Epinephelus nigritus) and ratified the morphology of the elongated spines of E. nigritus.