Ultraviolet radiation (UVR) in solar light is important for skin biology. It is involved in the development acute and chronic skin inflammation, aging and cancer, causing erythema, tanning and local or systemic immunosuppression. Omega-3 polyunsaturated fatty acids (n-3 PUFA) are considered anti- inflammatory and could reduce the damage caused by overexposure to UVR. Although, n-3 PUFA have been considered as photoprotective agents, their exact mechanisms of action is not completely understood. The aim of the work is to determine the effect of UVR and the n-3 PUFA eicosapentaenoic acid (EPA), or docosahexaenoic acid (DHA) on human skin cells (in vitro study), specifically on: cell viability, apoptosis and their metabolism through the cyclooxygenase and lipoxygenase pathways. Also, to study the cellular incorporation and effect of n-3 PUFA on the fatty acid profile of skin cells. A clinical study was undertaken to assess the incorporation of n-3 PUFA supplements in human skin. A clinical study was performed in 40 healthy women (active group) supplemented with 4g/day of EPA (70%) and DHA (10%) and 40 healthy women (placebo group) supplemented with 4g/day of glyceryl tricoprylate coprate (GTCC). After 3 months, both blood samples and skin punch biopsies were collected and analysed for fatty acids by gas chromatography (GC). HaCaT keratinocytes and 46BR.1N fibroblasts were cultured and treated with 10 and 50μM of either EPA, or DHA or oleic acid (OA) for 72h and exposed to 15 and 50 mJ/cm2. Cell viability was measured by the MTT assay and cell apoptosis by a colorimetric method, at 24h post UVR. Cells and culture media were analysed by GC and liquid chromatography tandem mass spectrometry (LC/ESI-MS/MS) to assess cellular fatty acids and production of eicosanoids. The clinical a study showed that in RBC saturated fatty acids (SFA) (44.27±7.43%) were the main fatty acid group followed by n-6 PUFA (29.61±5.53%). While in dermal tissue monounsaturated fatty acids (MUFA) (58.90±9.80%) was the main fatty acid group followed by SFA (27.06±6.78%). A significant increase in EPA, DHA and docosapentaenoic acid (DPA) was observed in RBC but only EPA was significantly increased in the dermis post n-3 PUFA supplementation. . The viability of HaCaT keratinocytes and 46BR.1N fibroblasts decreased post UVR and this was further reduced post PUFA treatment. Cell apoptosis increased when cells were exposed to UVR and further increased when cells were treated with EPA and DHA. . In HaCaT keratinocytes MUFA (54.22±8.82%) was the main fatty acid group followed by FAS (37.11±.9.16%), while SFA (51.94±8.68%) was the main group followed by MUFA (27.07±4.79) in 46BR.1N. Treated both cells with EPA and DHA showed significant increased in cellular EPA, DPA and DHA. 46BR.1N fibroblasts produced higher levels of prostaglandins (PG) compared to HaCaT keratinocytes: PGE2 and PGD2 were the main PG in both HaCaT (7.96±3.18 and 1.48±1.19 pg/million cell; respectively) and 46BR.1N with (44.2±23.00 and 17.1±9.71 pg/million cell; respectively). Significant increase in PGE1 and PGE2 occurred when cells were exposed to 15mJ/cm2 UVR. Treatment with n-3 PUFA decreased the level of PGE1 and PGE2, and increase production PGE3 at the baseline and post UVR. Both cell lines produced hydroxy fatty acids and the concentration of these mediators was higher in 46BR.1N than HaCaT. The concentrations of these mediators were significant increased post UVR: treatment with n-3 PUFA decreased the level of HODE and HETE, and increase production of HEPE and HDHA at baseline and post UVR. Overall, n-3PUFA treatment led to increases in the content of EPA and DHA on RBC, dermal tissue and human skin cell lines. EPA and DHA in skin cell lines appear to offer protection by increasing cellular apoptosis, decreasing inflammatory mediators specifically PGE2 and 12-HETE, and increasing anti-inflammatory mediators such as PGE3, 15-HEPE and 17-HDHA.

Background. Omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) may have different effects on cognitive health due to their anti- or pro-inflammatory properties. Methods. We aimed to prospectively examine the relationships between n-3 and n-6 PUFA contents in serum phospholipids with incident all-cause dementia and Alzheimer’s disease dementia (AD). We included 1264 non-demented participants aged 84 ± 3 years from the German Study on Ageing, Cognition, and Dementia in Primary Care Patients (AgeCoDe) multicenter-cohort study. We investigated whether fatty acid concentrations in serum phospholipids, especially eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), alpha-linolenic acid (ALA), linoleic acid (LA), dihomo-γ-linolenic acid (DGLA), and arachidonic acid (AA), were associated with risk of incident all-cause dementia and AD. Results. During the follow-up window of seven years, 233 participants developed dementia. Higher concentrations of EPA were associated with a lower incidence of AD (hazard ratio (HR) 0.76 (95% CI 0.63; 0.93)). We also observed that higher concentrations of EPA were associated with a decreased risk for all-cause dementia (HR 0.76 (95% CI 0.61; 0.94)) and AD (HR 0.66 (95% CI 0.51; 0.85)) among apolipoprotein E ε4 (APOE ε4) non-carriers but not among APOE ε4 carriers. No other fatty acids were significantly associated with AD or dementia. Conclusions. Higher concentrations of EPA were associated with a lower risk of incident AD. This further supports a beneficial role of n-3 PUFAs for cognitive health in old age.

No / Human saphenous vein endothelial cells (HSVECs) derived from primary cultures of adult human veins constitute an excellent in vitro model for studying human endothelial metabolism. In this study we report the14C-labelled prostanoid profile of HSVECs under resting and stimulated conditions and the effect of the n-3 polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid on them. Results indicate that HSVECs while under resting conditions produce mainly prostaglandin F2 ¿(PGF2 ¿). After stimulation with calcium ionophore A23187, the cells were found to synthesise PGI2, PGE2and PGF2¿as major products and thromboxane B2and PGD2as minor products. Production of14C-labelled hydroxyeicosatetraenoic acids was not detected. Eicosapentaenoic acid was found to inhibit basal and stimulated prostanoid production whereas docosahexaenoic acid inhibited basal but strongly increased stimulated prostanoid production. These results may offer the basis for further studies aiming to investigate targets for pharmacological intervention in inflammatory conditions.

Yes / Abstract Objective Omega-3 polyunsaturated fatty acids (PUFAs) have anticolorectal cancer (CRC) activity. The intestinal microbiota has been implicated in colorectal carcinogenesis. Dietary omega-3 PUFAs alter the mouse intestinal microbiome compatible with antineoplastic activity. Therefore, we investigated the effect of omega-3 PUFA supplements on the faecal microbiome in middle-aged, healthy volunteers (n=22). Design A randomised, open-label, cross-over trial of 8 weeks’ treatment with 4 g mixed eicosapentaenoic acid/docosahexaenoic acid in two formulations (soft-gel capsules and Smartfish drinks), separated by a 12-week ‘washout’ period. Faecal samples were collected at five time-points for microbiome analysis by 16S ribosomal RNA PCR and Illumina MiSeq sequencing. Red blood cell (RBC) fatty acid analysis was performed by liquid chromatography tandem mass spectrometry. Results Both omega-3 PUFA formulations induced similar changes in RBC fatty acid content, except that drinks were associated with a larger, and more prolonged, decrease in omega-6 PUFA arachidonic acid than the capsule intervention (p=0.02). There were no significant changes in α or β diversity, or phyla composition, associated with omega-3 PUFA supplementation. However, a reversible increased abundance of several genera, including Bifidobacterium, Roseburia and Lactobacillus was observed with one or both omega-3 PUFA interventions. Microbiome changes did not correlate with RBC omega-3 PUFA incorporation or development of omega-3 PUFA-induced diarrhoea. There were no treatment order effects. Conclusion Omega-3 PUFA supplementation induces a reversible increase in several short-chain fatty acid-producing bacteria, independently of the method of administration. There is no simple relationship between the intestinal microbiome and systemic omega-3 PUFA exposure. / NIHR/EME Yorkshire Cancer Research (YCR)

Eicosapentaenoic acid (EPA) is a polyunsaturated fatty acid (PUFA) with neuroprotective and cardioprotective properties. It is thought that some of the actions of EPA may be attributed to its elongated metabolite, the PUFA docosapentaenoic acid (DPA). Docosahexaenoic acid (DHA) and arachidonic acid (AA) are bioactive PUFA ubiquitously expressed in neural tissues. EPA and AA can be converted by cyclooxygenase (COX) to prostanoids and by lipoxygenase (LOX) to hydroxy fatty acids. PUFA can also be converted to ethanolamides in the brain. These mediators are involved in physiological and pathological processes in many bodily systems. The purpose of this study was to examine the production of eicosanoids, hydroxy fatty acids and fatty acid ethanolamides in young and aged rat brain following EPA or DPA enriched diets. The effects of specific PUFA on human platelet eicosanoid production were also investigated as these mediators play a role in adhesion and aggregation. Liquid chromatography coupled to tandem mass spectrometry (LC/ESI-MS/MS) assays were developed and used to measure lipid mediators in rat brain and human platelets. Ageing in rat brain was accompanied with several changes in the prostanoid and hydroxy fatty acid profiles. Supplementing the diet with EPA or DPA at a daily dose of 200 mg/kg for 8 weeks prevented these changes and decreased levels of PGE2. DPA changed the profile of hydroxy fatty acids synthesised in the brain tissue of young animals. This study has shown that levels of eicosapentaenoylethanolamide (EPA-EA) increase in the brain as a result of ageing and that this is accompanied by an increase in levels of anandamide. Feeding aged animals EPA or DPA further increased the levels of EPA-EA but prevented any change in the level of anandamide. Niacin is used to treat hypercholesterolaemia although it is associated with an unpleasant PGD2 mediated skin flush. This exploratory study has shown that human platelets treated with niacin did not show any changes in their prostanoid and hydroxy fatty acid profiles. Platelets treated with EPA showed increased production of TXB3 and 12-HEPE. Niacin augmented the effects of EPA on human platelet mediator synthesis. Overall, this study has demonstrated that EPA can change brain and platelet lipid mediator synthesis and has provided evidence that could explain some of the neuroprotective and cardioprotective actions of this PUFA.

No presente estudo avaliamos o impacto da adição de fluido folicular (FF) de mulheres inférteis sem e com endometriose em estágios iniciais (I/II) e avançados [(III/IV) sem e com endometrioma] ao meio de maturação in vitro (MIV) sobre as taxas de normalidade meiótica de oócitos bovinos. Avaliamos se a L-carnitina (LC) e os ácidos graxos ômega-3 [n3, ácidos docosahexaenóico (DHA) e eicosapentaenoico (EPA)] são capazes de prevenir os danos meióticos em oócitos bovinos induzidos por FF de mulheres inférteis com endometriose I/II e III/IV durante a MIV. Para isso, realizamos um estudo experimental utilizando modelo bovino. Trinta e duas amostras de FF foram colhidas de 24 mulheres inférteis com endometriose (8 com I/II, 8 com III/IV sem endometrioma e 8 III/IV com endometrioma no ciclo) e 8 sem endometriose (controle) que foram submetidas à estimulação ovariana controlada para realização de injeção intracitoplasmática de espermatozoide. Complexos cumulus-oócitos (CCOs) imaturos de bovinos foram submetidos à MIV divididos em 9 grupos: sem FF (sem-FF), com 1% de FF de mulheres inférteis sem endometriose (FFControle) e com endometriose (FFEI/II, FFEIII/IV e FFEendometrioma) suplementados ou não com LC (0,6mg/mL) e ácidos graxos ômega-3 (0,4 nM de DHA e 0,6 nM de EPA) (FFControle+LC+n3, FFEI/II+LC+n3, FFEIII/IV+LC+n3 e FFEendometrioma+LC+n3). Após 22-24h de MIV, os oócitos foram denudados, fixados e armazenados para realização de imunofluorescência para visualização do fuso meiótico e cromossomos por microscopia confocal. As taxas de metáfase II (MII) e de MII normais foram comparadas entre os 9 grupos utilizando o teste do qui-quadrado (p<0,05). Um total de 1686 CCOs imaturos foram submetidos à MIV, e 1401 oócitos foram visualizados por microscopia confocal. A adição de FF de mulheres com endometriose ao meio de MIV reduziu a taxa de MII normais (FFEI/II: 62,2%, FFEIII/IV: 70,2% e FFEendometrioma: 72,7%) comparado aos grupos sem-FF (87,2%) e FFControle (87,2%). O grupo FFEendometrioma (69,3%) apresentou a menor taxa de MII comparado a todos os demais grupos (sem-FF: 91,9%, FFControle: 89,2%, FFControle+LC+n3: 89,2%, FFEI/II: 85,4%, FFEI/II+LC+n3: 85,3%, FFEIII/IV: 80,7%, FFEIII/IV+LC+n3: 90,8%, FFEndometrioma+LC+n3: 86,4%). O grupo FFEIII/IV apresentou menor taxa de MII comparado ao grupo sem-FF. No grupo com FFControle, a adição de LC+n3 não alterou as taxas de MII (89,2% vs 89,2) e de MII normais (87,2% vs 82,5%). No grupo FFEI/II, a adição de LC+n3 aumentou a taxa de MII normais (84,5% vs. 62,2%). No grupo FFEIII/IV a adição de LC+n3 aumentou a taxa de MII normais (70,2% vs 84,1%) e de MII (90,8%), que passou a ser semelhante a dos grupos sem-FF e FFControle. No grupo FFEendometrioma a adição de LC+n3 aumentou a taxa de MII normais (86,4%), comparado ao grupo FFEendometrioma (69,3%), a qual foi similar a dos grupos sem-FF e FFControle. Portanto, o FF de mulheres com endometriose prejudica o fuso meiótico e o alinhamento cromossômico de oócitos bovinos, independentemente, do estágio da doença. Entretanto, o avanço da endometriose e a presença de endometrioma parecem ter um impacto ainda mais negativo na qualidade oocitária, prejudicando também a maturação nuclear. A adição de LC+n3 previne os danos meióticos oocitários provocados pelo FF de mulheres com endometriose em estágios iniciais e avançados. Dessa forma, sugerimos que inflamação, o estresse oxidativo e a desregulação da ?-oxidação são fatores envolvidos na alteração da qualidade oocitária e, consequente, piora da fertilidade natural de mulheres com endometriose. / In the present study, we evaluated the impact of the addition of follicular fluid (FF) from infertile women without and with endometriosis in the early (I/II) and advanced stages [(III/IV) with and without endometrioma] to the in vitro maturation (IVM) medium on the meiotic normality rates of bovine oocytes. We evaluated whether L-carnitine (LC) and omega-3 fatty acids [n3, docosahexaenoic (DHA) and eicosapentaenoic acid (EPA)] were able to prevent bovine meiotic oocyte damage induced by FF from infertile women with endometriosis in stages I/II and III/IV during IVM. For this, we performed an experimental study using bovine model. Thirty-two FF samples were collected from 24 infertile women with endometriosis (8 with I/II, 8 with III/IV without endometrioma and 8 III/IV with endometrioma in the cycle) and 8 without endometriosis (control) who underwent to controlled ovarian stimulation for intracytoplasmic sperm injection. Immature cumulus oocytes complexes(COCs) of bovines were submitted to IVM divided into 9 groups: without FF (No-FF), with 1% FF of infertile women without endometriosis (FFControl) and with endometriosis (FFEI/II, FFEIII/IV and FFEendometrioma) supplemented or not with LC (0.6 mg/mL) and omega-3 fatty acids (0.4 nM DHA and 0.6 nM EPA) (FFControl+LC+n3, FFEI/II+LC+n3, FFEIII/IV+LC+n3 and FFEendometrioma+LC+n3). After 22-24h of IVM, the oocytes were denuded, fixed and stored for subsequent immunofluorescence to visualize the meiotic spindle and chromosomes by confocal microscopy. The metaphase II (MII) and normal MII rates were compared between the 9 groups using the chi-square test (p <0.05). A total of 1686 immature COCs were submitted to IVM, and 1401 oocytes were visualized by confocal microscopy. Addition of FF from women with endometriosis to the IVM medium decreased the rate of normal MII (FFEI/II: 62.2%, FFEIII/IV: 70.2% and FFEendometrioma: 72.7%) compared to the No-FF (87.2%) and FFControl (87.2%) groups. The FFEendometrioma group (69.3%) presented the lowest rate of MII compared to all other groups (No-FF: 91.9%, FFControl: 89.2%, FFControl+LC+n3: 89.2%, FFEI/II: 85.4%, FFEI/II+LC+n3: 85.3%, FFEIII/IV: 80.7%, FFEIII/IV+LC+n3: 90.8%, FFEndometrioma+LC+n3: 86.4%). The FFEIII/IV group had a lower MII rate compared to the No-FF group. In the group with FFControl, the addition of LC+n3 did not change the rates of MII (89.2% vs 89.2%) and normal MII (87.2% vs 82.5%). In the FFEI/II group, the addition of LC+n3 increased the normal MII rate (84.5% vs 62.2%). In the FFEIII/IV group, the addition of LC+n3 increased the normal MII rate (70.2% vs 84.1%) and MII (90.8%), which was similar to that of the No-FF and FFControl. In the FFEendometrioma group, the addition of LC+n3 increased the normal MII rate (69.3% vs 86.4%) which was similar to No-FF and FFControl groups. Therefore, the FF of women with endometriosis impairs the meiotic spindle and the chromosomal alignment of bovine oocytes, regardless of the stage of the disease. However, the progression of endometriosis and the presence of endometrioma appear to have an even more negative impact on oocyte quality, and also impairs nuclear maturation. The addition of LC+n3 prevents meiotic oocyte damages induced by FF from women with endometriosis in the early and advanced stages. Thus, we suggest that inflammation, oxidative stress and deregulation of ?-oxidation are factors involved in the alteration of oocyte quality and, consequently, worsening of the natural fertility of women with endometriosis.

Mehrfach ungesättigte omega-3 Fettsäuren (n-3 PUFAs), wie Eicosapentaensäure (EPA) und Docosahexaensäure (DHA), schützen vor kardiovaskulären Erkrankungen, wie tödlichen Arrhythmien. In vitro Untersuchungen belegen, dass rekombinante Cytochrom P450 (CYP) Enzyme nicht nur die n-6 PUFA Arachidonsäure (AA), sondern auch die n-3 PUFAs EPA und DHA als alternative Substrate verwenden. Dabei entstehen bioaktive regio- und stereoisomere Epoxy- und Hydroxymetaboliten, CYP-Eicosanoide, die als sekundäre Botenstoffe bei der Regulation von Gefäß-, Nieren- und Herzfunktionen fungieren. Die genauen molekularen Mechanismen dieser Metabolite sind noch weitgehend unerforscht. In der vorliegenden Arbeit wurde zunächst der ernährungsbedingte Einfluss auf das endogene CYP-Eicosanoidprofil im Menschen untersucht. Die Ergebnisse der klinischen Studie zeigten, dass n-3 PUFAs auch in vivo alternative Substrate von CYP-Enzymen darstellen und wenn verfügbar sogar effektiver zu ihren Metaboliten umgesetzt wurden als AA. Als ein wichtiger Metabolit entsteht nach EPA/DHA-Supplementation 17,18-EEQ, welcher womöglich der eigentliche Vermittler der kardioprotektiven Effekte von n-3 PUFAs ist. Unter Verwendung eines etablierten Zellmodells mit spontan schlagenden neonatalen Rattenkardiomyozyten (NRKMs) wurde der anti-arrhythmische Effekte von 17,18-EEQ genauer untersucht. Der negativ chronotrope Effekt von EPA auf NRKMs wurde tatsächlich durch 17,18-EEQ vermittelt, insbesondere dem R,S-Enantiomer. Mittels Strukturfunktionsanalyse wurden synthetische Analoga mit gleicher Wirksamkeit wie dem 7,18-EEQ gefunden, wobei strikte strukturelle Merkmale für die biologische Funktion identifiziert wurden. Die Suche nach einem molekularen Ziel für CYP-Epoxyeicosanoide führte zu einem möglichen Rezeptorkandidaten, der hinsichtlich seiner Ligandenspezifität untersucht wurde. Dieser oder zukünftige andere Rezeptorkandidaten stellen ein mögliches neues zelluläres Ziel zur Behandlung kardialer Arrhythmien dar. / The n-3 polyunsaturated fatty acids (n-3 PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), protect from cardiovascular disease, especially from fetal arrhythmia. Moreover, in vitro studies proved that recombinant cytochrome P450 (CYP) enzymes not only accept the physiologically most important n-6 PUFA arachidonic acid (AA), but also EPA and DHA as alternative substrates, thereby generating regio- and stereospecific biologically active epoxy- and hydroxymetabolites, CYP-eicosanoids. These metabolites serve as second messengers regulating vascular, renal and cardiac function. The precise underlying molecular mechanisms are only partially understood and need further investigation. The first aim of the thesis was to show that the endogenous CYP-eicosanoid profile depends on the availability of the precursor fatty acids. The results of a clinical trial with 20 volunteers, show that n-3 PUFAs serve also in vivo as alternative CYP-dependent substrates and are even preferentially metabolized compared to AA. After EPA/DHA-supplementation 17,18 EEQ was generated as a major metabolite, potentially an important mediator of cardiovascular effects originally attributed to n-3 PUFAs. To test the anti-arrhythmic effect of EPA and 17,18-EEQ, an established cell model with neonatal rat cardiomyocytes (NRKMs) was used. The negative chronotropic effect of EPA was mimicked by 17,18-EEQ, attributed only to the R,S-enantiomer. A structure activity relationship study revealed synthetic analogs, exerting the same biological effect as 17,18-EEQ. Strict structural requirements were found for agonistic function, hinting at a specific interaction with cellular targets, like GPCRs. The search of a molecular target of CYP-eicosanoids led to a putative receptor, which was tested for ligand binding specificity. If the preliminary results on the ligand binding are confirmed in future experiments this receptor might be a novel target for the treatment of cardiac arrhythmia.

Ultraviolet radiation (UVR) in solar light is important for skin biology. It is involved in the development acute and chronic skin inflammation, aging and cancer, causing erythema, tanning and local or systemic immunosuppression. Omega-3 polyunsaturated fatty acids (n-3 PUFA) are considered anti- inflammatory and could reduce the damage caused by overexposure to UVR. Although, n-3 PUFA have been considered as photoprotective agents, their exact mechanisms of action is not completely understood. The aim of the work is to determine the effect of UVR and the n-3 PUFA eicosapentaenoic acid (EPA), or docosahexaenoic acid (DHA) on human skin cells (in vitro study), specifically on: cell viability, apoptosis and their metabolism through the cyclooxygenase and lipoxygenase pathways. Also, to study the cellular incorporation and effect of n-3 PUFA on the fatty acid profile of skin cells. A clinical study was undertaken to assess the incorporation of n-3 PUFA supplements in human skin. A clinical study was performed in 40 healthy women (active group) supplemented with 4g/day of EPA (70%) and DHA (10%) and 40 healthy women (placebo group) supplemented with 4g/day of glyceryl tricoprylate coprate (GTCC). After 3 months, both blood samples and skin punch biopsies were collected and analysed for fatty acids by gas chromatography (GC). HaCaT keratinocytes and 46BR.1N fibroblasts were cultured and treated with 10 and 50μM of either EPA, or DHA or oleic acid (OA) for 72h and exposed to 15 and 50 mJ/cm2. Cell viability was measured by the MTT assay and cell apoptosis by a colorimetric method, at 24h post UVR. Cells and culture media were analysed by GC and liquid chromatography tandem mass spectrometry (LC/ESI-MS/MS) to assess cellular fatty acids and production of eicosanoids. The clinical a study showed that in RBC saturated fatty acids (SFA) (44.27±7.43%) were the main fatty acid group followed by n-6 PUFA (29.61±5.53%). While in dermal tissue monounsaturated fatty acids (MUFA) (58.90±9.80%) was the main fatty acid group followed by SFA (27.06±6.78%). A significant increase in EPA, DHA and docosapentaenoic acid (DPA) was observed in RBC but only EPA was significantly increased in the dermis post n-3 PUFA supplementation. . The viability of HaCaT keratinocytes and 46BR.1N fibroblasts decreased post UVR and this was further reduced post PUFA treatment. Cell apoptosis increased when cells were exposed to UVR and further increased when cells were treated with EPA and DHA. . In HaCaT keratinocytes MUFA (54.22±8.82%) was the main fatty acid group followed by FAS (37.11±.9.16%), while SFA (51.94±8.68%) was the main group followed by MUFA (27.07±4.79) in 46BR.1N. Treated both cells with EPA and DHA showed significant increased in cellular EPA, DPA and DHA. 46BR.1N fibroblasts produced higher levels of prostaglandins (PG) compared to HaCaT keratinocytes: PGE2 and PGD2 were the main PG in both HaCaT (7.96±3.18 and 1.48±1.19 pg/million cell; respectively) and 46BR.1N with (44.2±23.00 and 17.1±9.71 pg/million cell; respectively). Significant increase in PGE1 and PGE2 occurred when cells were exposed to 15mJ/cm2 UVR. Treatment with n-3 PUFA decreased the level of PGE1 and PGE2, and increase production PGE3 at the baseline and post UVR. Both cell lines produced hydroxy fatty acids and the concentration of these mediators was higher in 46BR.1N than HaCaT. The concentrations of these mediators were significant increased post UVR: treatment with n-3 PUFA decreased the level of HODE and HETE, and increase production of HEPE and HDHA at baseline and post UVR. Overall, n-3PUFA treatment led to increases in the content of EPA and DHA on RBC, dermal tissue and human skin cell lines. EPA and DHA in skin cell lines appear to offer protection by increasing cellular apoptosis, decreasing inflammatory mediators specifically PGE2 and 12-HETE, and increasing anti-inflammatory mediators such as PGE3, 15-HEPE and 17-HDHA.

The gilthead seabream (Sparus aurata) and European seabass (Dicentrarchus labrax) require n-3 long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), for optimal growth and health. Due to the rapid growth of global aquaculture the quantity of marine oils used in aquafeeds has been limited, yet the overall quantity of oil in an aquafeed has increased by the addition of vegetable oil (VO) to supply dietary energy. For aquaculture to continue to grow more fish must be produced with less marine ingredients, yet EPA and DHA must be maintained at levels above fish requirements. This project set out to re-evaluate the requirement for EPA and DHA in gilthead seabream and European seabass. Two dose-response studies were designed and executed where juvenile seabream and seabass were fed one of six levels of EPA+DHA (0.2 – 3.2 % as fed). Biometric data were collected and analysed to determine new requirement estimates for EPA+DHA for fish of two weight ranges (24 – 80 g and 80 – 200 g). The effects of the dietary LC-PUFA gradient on lipid composition and metabolism were also considered.

Lipids are important for structural and physiological functions of neuronal cell membranes. They exhibit a range of biological effects many are bioactive lipid mediators derived from polyunsaturated fatty acids such as sphingolipids, fatty acid ethanolamides (FA-EA) and endocannabinoids (EC). These lipid mediators and oxysterols elicit potent bioactive functions in many physiological and pathological processes of the brain and neuronal tissues. They have been investigated for biomarker discovery of ageing, neuroinflammation and neurodegenerative disorders. The n-3 fatty acids EPA and DPA are thought to exhibit a range of neuroprotective effects many of which are mediated through production of such lipid mediators. The aims of this study were to evaluate the effects of n-3 EPA and n-3 DPA supplementation on RBC membranes and in this way assess dietary compliance and to investigate brain sphingomyelin species of adult and aged rats supplemented with n-3 EPA and n-3 DPA to evaluate the effects and benefits on age-related changes in the brain. Furthermore, to study the effects of lithium on the brain FA-EAs and ECs to further understand the neuroprotective effects of lithium neuroprotective action on neuroinflammation as induced by LPS. Finally to examine if circulating oxysterols are linked to the prevalence of ALS and whether RBC fatty acids are markers of this action in relation to age and disease stages. These analytes were extracted from tissue samples and analysed with GC, LC/ESI-MS/MS and GC-MS. It was found that aged rats exhibited a significant increase in brain AA and decrease in Σn-3 and Σn-6 PUFAs when compared to adult animals. The observed increase of brain AA was reversed following n-3 EPA and n-3 DPA supplementation. Sphingomyelin was significantly increased when aged animals were supplemented with n-3 DPA. LPS treatment following lithium supplementation increased LA-EA and ALA-EA, while it decreased DHA-EA. Both oxysterols 24-OH and 27-OH increased in ALS patients and SOD1-mice. Eicosadienoic acid was different in ASL-patients compared to aged SOD1-mice. These studies demonstrated that dietary intake of n-3 EPA and n-3DPA significantly altered RBC fatty acids and sphingolipids in rat brain. They suggest that n-3 DPA can be a potential storage form for EPA, as shown by retro-conversion of n-3 DPA into EPA in erythrocyte membranes, ensuring supply of n-3 EPA. Also, n-3 EPA and n-3 DPA supplementation can contribute to an increase in brain sphingomyelin species with implications for age effects and regulation of brain development. Effects of lithium highlight novel anti-neuroinflammatory treatment pathways. Both 24-hydroxycholesterol and eicosadienoic acid may be used as biomarkers in ALS thereby possibly helping to manage the progressive stages of disease.