Simultaneous Determination of Prostaglandin and Hormones in Excreta of Trogopterus xanthipes.

The excreta of Trogopterus xanthipes (also called Wulingzhi in Chinese, WLZ) is a well-known traditional Chinese medicine used for the treatment of irregular menstruation in clinic. Few reports are available on the chemical profiling of WLZ. In this work, qualitative and quantitative analyses of endogenous prostaglandin and hormones in WLZ were performed using UHPLC-orbitrap-MSn. In total, 48 compounds were identified in urine of T. xanthipes. Furthermore, the contents of four target compounds were simultaneously quantitated in 20 batches of samples by UPLC-MS/MS. The quantitative method showed a good linear correlation (R > 0.995) in a wide range for each compound. The method had a high sensitivity with LOD (0.5-1.0 ng/mL) and LOQ (1.0-2.5 ng/mL). The intra- and inter-day precisions were < 9.17 (RSD %), and repeatability and stability were < 6.14 (RSD %). The recovery of the analytes varied between 85.8% and 97.3% at three different concentrations. The present integrated qualitative and quantitative assessment of WLZ provides an evaluation strategy to assess the constituent in traditional Chinese medicine.

Lipidomic methodologies for biomarkers of chronic inflammation in nutritional research: ω-3 and ω-6 lipid mediators.

The evolutionary history of hominins has been characterized by significant dietary changes, which include the introduction of meat eating, cooking, and the changes associated with plant and animal domestication. The Western pattern diet has been linked with the onset of chronic inflammation, and serious health problems including obesity, metabolic syndrome, and cardiovascular diseases. Diets enriched with ω-3 marine PUFAs have revealed additional improvements in health status associated to a reduction of proinflammatory ω-3 and ω-6 lipid mediators. Lipid mediators are produced from enzymatic and non-enzymatic oxidation of PUFAs. Interest in better understanding the occurrence of these metabolites has increased exponentially as a result of the growing evidence of their role on inflammatory processes, control of the immune system, cell signaling, onset of metabolic diseases, or even cancer. The scope of this review has been to highlight the recent findings on: a) the formation of lipid mediators and their role in different inflammatory and metabolic conditions, b) the direct use of lipid mediators as antiinflammatory drugs or the potential of new drugs as a new therapeutic option for the synthesis of antiinflammatory or resolving lipid mediators and c) the impact of nutritional interventions to modulate lipid mediators synthesis towards antiinflammatory conditions. In a second part, we have summarized methodological approaches (Lipidomics) for the accurate analysis of lipid mediators. Although several techniques have been used, most authors preferred the combination of SPE with LC-MS. Advantages and disadvantages of each method are herein addressed, as well as the main LC-MS difficulties and challenges for the establishment of new biomarkers and standardization of experimental designs, and finally to deepen the study of mechanisms involved on the inflammatory response.

Heterocyclic homoprostanoid derivative attenuates monoarthritis in rats: An in vitro and in vivo preclinical paradigm.

From our lab, among the nineteen heterocyclic homoprostanoids (HHPs), three derivatives (compounds 3, 3b and 3c) exerted antioxidant and anti-inflammatory activity. Present study is an extension of the earlier work, and, is designed to establish their therapeutic potential in monoarthritis in rats. In addition, their possible mechanism of action would be investigated. A battery of in vitro tests such as lipopolysaccharide (LPS)-induced nitrite (NO)/reactive oxygen species (ROS) and NO/interleukin (IL)-6 generation in murine macrophages and whole blood (WhB), respectively were conducted. Later, in vitro cyclooxygenase (COX) enzyme inhibitory activity was also evaluated. All the tested compounds showed comparable efficacy against ROS and NO in LPS-stimulated murine macrophages. However, compound 3 did not exert inhibitory effect on LPS-induced NO/IL-6 generation in WhB assay. Compounds (3b and 3c) inhibited the NO generation in LPS-stimulated WhB. However, only compound 3b reversed the raised IL-6 levels in this assay. None of the test compounds inhibited COX iso-enzymes in the in vitro assay. All three HHPs showed comparable efficacy against carrageenan-induced paw inflammation. However, none of them exhibited any dose-dependent effect in this model. Based upon previous reports, compound 3c was explored against adjuvant-induced monoarthritis (AIA) in male Sprague-Dawley rats, where it exerted promising therapeutic effect. In addition to radiological and histological examinations of tibio-tarsal joint, various parameters such as chronic inflammation/pain, clinical score, interleukin (IL)-6 levels and complete blood cell profile were evaluated in AIA rats. Chronic treatment with 3c halted the disease progression in rats, improved the overall health of animals, as demonstrated by haematological, clinical scoring and joint examinations (radiological and histopathological). Inhibitory effect on elevated IL-6 in AIA rats suggested the possible mechanism of 3c on cytokine signalling. Overall, the study supports the anti-arthritic potential of compound 3c.

Effect of pre-partum feed supplementation on post-partum ovarian activity, milk production and calf growth of small holder dairy Cattle in Cameroon.

Seventy-two cows were selected for an on-farm study on the effect of feed supplementation before calving on milk production, ovarian activity and calf growth of Holstein, indigenous Red Fulani cows and their crosses. Pre-partum feed supplementation was done using cotton seed cake (80%), maize (18%), bone meal (1%) and kitchen salt (1% NaCl). Supplementation levels consisted of a low supplementation fed at 1 kg per animal per day and high supplementation fed at 2 kg per animal per day. In addition, Red Fulani cows received the supplements in two different ways namely a pre-partum supplementation consisting of 1 kg per cow per day and pre- and post-partum supplementation consisting of 1 kg per cow per day before calving and 1 kg per cow per day post-partum up to 30 days after calving. Blood samples were analysed using ELISA Progesterone kits to determine the length of post-partum anoestrus. Results show that pre-partum levels of feeding did not have any effect (P > 0.05) on body condition score (BCS) at 12 weeks after calving, calf birth weight, average daily weight gain of calves, milk production and post-partum anoestrus. High BCS at calving was shown to influence BCS at 12 weeks of lactation. Holstein cows had bigger calves (P < 0.01) at birth (45 kg) compared to traditional cows (36 kg) and crosses (34 kg). There was little benefit of pre-partum supplementation on the parameters investigated in this study. Consequently, low income farmers are advised to concentrate their efforts of supplementation early in lactation.

Organotypical vascular model for characterization of radioprotective compounds: studies on antioxidant 2,3-diaryl-substituted indole-based cyclooxygenase-2 inhibitors.

Radiotherapy of various cancers is closely associated with increased cardiovascular morbidity and mortality. Arachidonic acid metabolites are supposed to play a key role in radiation-induced vascular dysfunction. This study was designed to evaluate the effects of novel, antioxidative 2,3-diaryl-substituted indole-based selective cyclooxygenase-2 (COX-2) inhibitors (2,3-diaryl-indole coxibs) on radiation-induced formation of arachidonic acid metabolites via COX-2 and oxidant stress pathways in an organotypical vascular model of rat aortic rings. Acute and subacute effects of X-ray radiation (4 and 10 Gy; 1 and 3 days post irradiation) with or without the presence of 1 µM of the 2,3-diaryl-indole coxib 2-[4-(aminosulfonyl)phenyl]-3-(4-methoxyphenyl)-1H-indole (C1) or celecoxib as reference compared to sham-irradiated controls were assessed. The following parameters were measured: metabolic activity of the aortic rings; induction and regulation of COX-2 expression; release of prostaglandin E2 and F2α-isoprostane. Irradiation without presence of coxibs resulted in a dose-dependent augmentation of all parameters studied. When aortic rings were exposed to the 2,3-diaryl-indole coxib 1 h before irradiation, metabolic activity was restored and the release of both prostaglandin and isoprostane was inhibited. The latter indicates a direct interaction with oxidant stress pathways. By contrast, celecoxib exhibited only slight effects on the formation of isoprostane. The reduction of radiation-induced vascular dysfunction by antioxidative coxibs may widen the therapeutic window of COX-2 targeted treatment.

Multiplexed phosphospecific flow cytometry enables large-scale signaling profiling and drug screening in blood platelets.

BACKGROUND: Dissecting the signaling events that contribute to platelet activation will increase our understanding of platelet function and aid in the development of new antiplatelet agents. However, high-throughput methodology for the quantitative analysis of platelet signaling events is still lacking. OBJECTIVE: To develop a high-throughput assay for the analysis of platelet signaling events in whole blood. METHODS AND RESULTS: We developed a fluorescent barcoding protocol to facilitate multiplexing and enable large-scale signaling profiling in platelets in whole blood. The methodology allowed simultaneous staining and acquisition of 24-96 samples in a single analysis tube with a standard flow cytometer. This approach significantly reduced experimental numbers, data acquisition time, and antibody consumption, while providing automated statistically rich quantitative data on signaling events. Using vasodilator-stimulated phosphoprotein (VASP), an established marker of platelet inhibition and antiplatelet drug therapy, we demonstrated that the assay could detect subtle changes in phosphoVASP-Ser157/239 in response to cAMP-elevating agents of varying potency and known modulators of the cAMP signaling cascade. The assay could be used with washed platelets or whole blood, analyzed immediately or frozen, without any significant change in assay performance. To demonstrate the usefulness of the assay as a drug discovery platform, we examined a prostaglandin screening library. Our screen of 70 prostaglandin derivatives revealed three previously uncharacterized lipids that stimulated phosphorylation of VASP-Ser157. Follow-up analyses demonstrated that these agents elevated intraplatelet cAMP and inhibited collagen-induced platelet aggregation. CONCLUSIONS: This novel method enables rapid, large-scale quantitative signaling profiling and compound screening in human platelets present in whole blood.

Anti-inflammatory potential of alpha-linolenic acid mediated through selective COX inhibition: computational and experimental data.

The present work investigates the anti-inflammatory activity of alpha-linolenic acid (ALA) and linoleic acid (LA) using computational and experimental analysis. The binding affinity of ALA and LA was appraised for cyclooxygenase 1 (COX-1), cyclooxygenase 2 (COX-2), and 5-lipoxygenase (5-LOX) using AutoDock 4.2 and AutoDock Vina 1.1.2. Anti-inflammatory activity of ALA (2 and 4 ml/kg, i.p.) (55.65 % v/v) and LA (2 and 4 ml/kg, i.p.) (55 % v/v) was further assayed using the rat paw edema test against a variety of phlogistic agents including carrageenan, arachidonic acid, prostaglandin, and leukotriene, respectively. ALA (2 and 4 ml/kg, i.p.) and LA (2 and 4 ml/kg, i.p.) were further tested for their efficacy against complete Freund's adjuvant (CFA)-induced (0.05 ml) arthritis in albino rats. Following CFA-induced arthritis, ALA and LA were tested for their inhibitory proficiency against COX-1, COX-2, and 5-LOX in vitro. The present study commends that the anti-inflammatory potential of ALA could be attributed to COX inhibition, in particular, COX-2.

Prostaglandin analogous and antioxidant activity mediated gastroprotective action of Tabernaemontana divaricata (L.) R. Br. flower methanolic extract against chemically induced gastric ulcers in rats.

The present study was conducted to evaluate the antiulcerogenic effect and recognize the basic mechanism of action of Tabernaemontana divaricata (L.) R. Br. flowers. T. divaricata flower methanolic extract (TDFME) was screened for antiulcer activity versus aspirin and ethanol induced gastric ulcers at three doses--125, 250, and 500 mg/kg--orally using misoprostol as a standard. Besides histopathological examination, seven parameters, that is, ulcer index, total protein, nonprotein sulphhydryls, mucin, catalase, malondialdehyde, and superoxide dismutase levels, were estimated. In addition to HPLC profiling, GC-MS analysis and electrospray ionization--high resolution mass spectral (ESI-HRMS) analysis of crude TDFME were carried out in an attempt to identify known phytochemicals present in the extract on the basis of m/z value. The results revealed a significant increase in the levels of catalase, superoxide dismutase, mucin, and nonprotein sulphhydryls, while they revealed a reduction in ulcer index, the levels of total protein, and malondialdehyde. Histopathological observations also demonstrated the protective effect. Though all the doses of TDFME exhibited gastroprotective function, higher doses were found to be more effective. Mass spectral analysis gave a few characteristic m/z values suggesting the presence of a few known indole alkaloids, while HPLC profiling highlighted the complexity of the extract. TDFME was found to exhibit its gastroprotective effect through antioxidant mechanism and by enhancing the production of gastric mucous.

Δ12-prostaglandin J3, an omega-3 fatty acid-derived metabolite, selectively ablates leukemia stem cells in mice.

Targeting cancer stem cells is of paramount importance in successfully preventing cancer relapse. Recently, in silico screening of public gene-expression datasets identified cyclooxygenase-derived cyclopentenone prostaglandins (CyPGs) as likely agents to target malignant stem cells. We show here that Δ(12)-PGJ(3), a novel and naturally produced CyPG from the dietary fish-oil ω-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA; 20:5) alleviates the development of leukemia in 2 well-studied murine models of leukemia. IP administration of Δ(12)-PGJ(3) to mice infected with Friend erythroleukemia virus or those expressing the chronic myelogenous leukemia oncoprotein BCR-ABL in the hematopoietic stem cell pool completely restored normal hematologic parameters, splenic histology, and enhanced survival. More importantly, Δ(12)-PGJ(3) selectively targeted leukemia stem cells (LSCs) for apoptosis in the spleen and BM. This treatment completely eradicated LSCs in vivo, as demonstrated by the inability of donor cells from treated mice to cause leukemia in secondary transplantations. Given the potency of ω-3 polyunsaturated fatty acid-derived CyPGs and the well-known refractoriness of LSCs to currently used clinical agents, Δ(12)-PGJ(3) may represent a new chemotherapeutic for leukemia that targets LSCs.

The occurrence of 15-keto-prostaglandins in the red alga Gracilaria verrucosa.

New 15-keto-prostaglandins (1-4) were isolated from the MeOH extract of the red alga, Gracilaria verrucosa. Their structures were determined to be prostaglandin B congeners (1-3) and a prostaglandin E congener (4) based on the NMR and MS data. Prostaglandins with a C-15 keto function are rare from natural sources. The presence of these metabolites in the alga is notable because 15-keto-prostaglandins (15-keto-PGs) are considered to be the metabolic products of regular prostaglandins in mammals. The occurrence of different prostaglandins in this alga might be due to the existence of different oxidative enzymes, as previously mentioned for oxygenated fatty acids of the red alga Gracilariopsis lemaneiformis. The antiinflammatory activity of these prostaglandins was examined by evaluating their inhibitory effects on nitric oxide production in lipopolysaccharide (LPS)-activated RAW264.7 murine macrophage cells. These prostaglandins showed weak activity on nitric oxide production.

Prostaglandin-like fatty acid derivatives from Artemisia anomala.

Four prostaglandin-like fatty acid derivatives anomalone A-D (1-4) were isolated from the aerial part of Artemisia anomala S. Moore. Their structures were determined on the basis of extensive spectroscopic analyses.

Interaction of the human prostacyclin receptor with Rab11: characterization of a novel Rab11 binding domain within alpha-helix 8 that is regulated by palmitoylation.

The human prostacyclin receptor (hIP) undergoes agonist-induced internalization and subsequent recyclization in slowly recycling endosomes involving its direct physical interaction with Rab11a. Moreover, interaction with Rab11a localizes to a 22-residue putative Rab11 binding domain (RBD) within the carboxyl-terminal tail of the hIP, proximal to the transmembrane 7 (TM7) domain. Because the proposed RBD contains Cys(308) and Cys(311), in addition to Cys(309), that are known to undergo palmitoylation, we sought to identify the structure/function determinants of the RBD, including the influence of palmitoylation, on agonist-induced trafficking of the hIP. Through complementary approaches in yeast and mammalian cells along with computational structural studies, the RBD was localized to a 14-residue domain, between Val(299) and Leu(312), and proposed to be organized into an eighth alpha-helical domain (alpha-helix 8), comprising Val(299)-Val(307), adjacent to the palmitoylated residues at Cys(308)-Cys(311). From mutational and [(3)H]palmitate metabolic labeling studies, it is proposed that palmitoylation at Cys(311) in addition to agonist-regulated deacylation at Cys(309) > Cys(308) may dynamically position alpha-helix 8 in proximity to Rab11a, to regulate agonist-induced intracellular trafficking of the hIP. Moreover, Ala-scanning mutagenesis identified several hydrophobic residues within alpha-helix 8 as necessary for the interaction with Rab11a. Given the diverse membership of the G protein-coupled receptor superfamily, of which many members are also predicted to contain an alpha-helical 8 domain proximal to TM7 and, often, adjacent to palmitoylable cysteine(s), the identification of a functional role for alpha-helix 8, as exemplified as an RBD for the hIP, is likely to have broader significance for certain members of the superfamily.

Central prostaglandins in food intake regulation.

Prostaglandin (PG) E(2) and PGD(2), produced in the mammalian central nervous system, are known to have a variety of central actions on sleep, body temperature, and pain response via G-protein-coupled seven-transmembrane receptors. We found that centrally administered PGE(2) suppressed food intake via the EP(4) receptor, whereas PGD(2) increased food intake via the DP(1) receptor coupled to the neuropeptide Y Y(1) receptor. In this review, we summarize roles of central PGs in food intake regulation and discuss the relation between PGs and neuropeptides controlling food intake.

Phosphate concentrations in antiglaucoma medication.

BACKGROUND: Eye drops may contain phosphates as part of their buffer system. In the presence of epithelial keratopathy a high concentration of phosphate favours corneal calcification. To date European legislation does not require a quantitative declaration of the phosphates since buffers are regarded as additives. The knowledge of the phosphate concentration in medications helps to prevent corneal calcifications. Our study gives an overview on the amount of phosphate contained in antiglaucoma drops. METHODS: 21 samples of commercially available antiglaucoma drops were tested. The quantification of phosphate was performed using the molybdate method on a Modular P autoanalyzer. RESULTS: 10 of 21 (47 %) glaucoma drops had a phosphate concentration above physiological levels (> 1.45 mmol/L). A concentration higher than 100 mmol/L was found in four preparations that contained timolol. CONCLUSIONS: Many antiglaucoma drops contain unphysiological levels of phosphate, very high concentrations are found in some beta-blockers. These preparations have the potential to favour the formation of insoluble crystalline calcium phosphate deposits when used on a damaged corneal surface, and should therefore be avoided.

Synthesis and biological evaluation of new cross-conjugated dienone marine prostanoid analogues.

The synthesis of a series of brominated cross-conjugated dienones, marine prostanoid analogues, was considered using two cyclopentannelation processes, from enamine (by a domino 3-aza Claisen/Mannich reaction) and from dioxolane ester alkylation followed by intramolecular Wittig reaction. All the compounds synthesized featured the same cross-conjugated dienone system, with a vicinal syn or anti diol on the omega-chain. The replacement of the omega-side-chain of the natural prostanoids with a 1-hydroxyphenyl-butyl moiety gave new prostanoids (32-34) with good cytotoxicities. In a second series of products, the possibility of a shorter alpha-side-chain bearing a simple phenyl ester was investigated. The results indicated a dramatic increase in the cytotoxicity (39, 40, 43, 44). Finally, in a third series, the omega-1-hydroxyphenyl-butyl was replaced by a 1-hydroxymethyloxybenzyl chain. These simpler compounds (45, 46, 47, 48, 60) are still highly cytotoxic, in the medium range of 60 nM, close to the value of natural punaglandins.

Characterization of 11-dehydro-thromboxane B2 recombinant antibody obtained by phage display technology.

Recombinant monoclonal antibodies specific for 11-dehydro-thromboxane B(2) (11D-TX) were isolated from the combinatorial libraries on a pComb3 phage-display vector using a magnetic cell sorting (MACS) system. The libraries were constructed from repertories of light and heavy-chains derived from the total RNA of 11D-TX conjugated keyhole limpet haemocyanin-immunized mice. Biotinylation of 11D-TX conjugated bovine serum albumin (BSA) was performed through free thiol groups on BSA using 1-biotinamido-4-[4'-(maleimidomethyl) cyclohexanecarboxamido] butane (Biotin-BMCC). Affinity bio-panning was performed to enrich the phage display libraries against biotinylated 11D-TX conjugated BSA with the MACS system. Results indicated that the selected anti-11D-TX Fab fragments expressed by E. coli exhibited a five-fold higher affinity for BSA conjugated 11D-TX compared to BSA alone and little specificity to other related compounds as determined by the binding assay and inhibition enzyme-linked immunosorbent assay (ELISA). This is the first report of an antibody against prostaglandin produced by phage display technology and also determination of the DNA sequence of this antibody. The MACS system was shown to be a simpler and more efficient method of panning than the conventional ELISA procedure. According to our results, we concluded that the phage display technique combined with the MACS system allowed the selection of the antibody with high affinity and some specificity.

Neurotrophic actions of novel compounds designed from cyclopentenone prostaglandins.

Previously we found that some cyclopentenone prostaglandin derivatives promoted neurite outgrowth from PC12 cells and dorsal root ganglia explants in the presence of nerve growth factor; and so we referred to them as neurite outgrowth-promoting prostaglandins (NEPPs). In this study, NEPPs protected HT22 cells against oxidative glutamate toxicity. NEPP6, one of the most effective promoters of neurite outgrowth in PC12 cells, protected the cells most potently among NEPPs 1--10. Several derivatives, NEPPs 11--19, were newly synthesized based on the chemical structure of NEPP6. NEPP11 had a more potent neuroprotective effect than NEPP6. NEPP11 also prevented the death of cortical neurons induced by various stimuli and reduced ischemic brain damage in mice. Biotinylated compounds of NEPPs were synthesized to investigate their cellular accumulation. NEPP6-biotin protected the cells and emitted potent signals from the cells. In contrast, biotinylated non-neuroprotective derivatives emitted much weaker signals. These results suggest that NEPPs are novel types of neurotrophic compounds characterized by their dual biological activities of promoting neurite outgrowth and preventing neuronal death and that their accumulation in the cells is closely associated with their neuroprotective actions.

Analysis of oxidative stress and wound-inducible dinor isoprostanes F(1) (phytoprostanes F(1)) in plants.

Isoprostanes F(2) are arachidonate autoxidation products in mammals that have been shown to be induced during several human disorders associated with enhanced free-radical generation. Isoprostanes F(2) represent not only extremely reliable markers of oxidative stress in vivo, but they also exert potent biological effects. Therefore, it has been postulated that isoprostanoids are mediators of oxidant injury in vivo. Higher plants, however, do not synthesize arachidonic acid or isoprostanes. Here we show that a series of isoprostane F(2) analogs termed phytoprostanes F(1) (previously dinor isoprostanes F(1)) are formed by an analogous pathway from alpha-linolenate in plants. High-performance liquid chromatography and gas chromatography-mass spectrometry methods using [(18)O](3)phytoprostanes F(1) as internal standard have been developed to quantify phytoprostanes F(1). In fresh peppermint (Mentha piperita) leaves, phytoprostanes F(1) were found in free form (76 ng/g of dry weight) and at about 150-fold higher levels esterified in lipids. It is notable that these levels of phytoprostanes F(1) are more than two orders of magnitude higher than the basal levels of isoprostanes F(2) in mammalian tissues. Furthermore, wounding, as well as butyl hydroperoxide or cupric acetate stress triggered a dramatic increase of free and esterified phytoprostanes F(1). Thus phytoprostanes F(1) may represent a sensitive measure of oxidative damage in plants similar to isoprostanes in mammals. However, one of the most exciting issues to be clarified is the possibility that linolenate-derived phytoprostanes F(1) exert biological activities in plants and/or animals.

Are isoprostanes a clinical marker for antioxidant drug investigation?

Numerous pathological conditions are suspected to involve free radical production as part of their pathogenic process. Therefore, a pharmacological control of oxidative stress could probably benefit many vascular, inflammatory or degenerative diseases. However, the development of antioxidant drugs and their clinical evaluation are limited by the absence of an accurate, reliable and easy-to-handle marker of tissue oxidative events. Isoprostanes (isoPs), a prostaglandin-related series of metabolites, are emerging as major candidates for clinical measurement of oxidative stress. They are chemically stable products of lipid peroxidation, formed in cellular membranes and subsequently released and excreted in the urine. Many recent clinical studies have reported that urinary and plasma levels of isoPs (in particular the iPF2alpha-III isomer also called 8-epi-PGF2alpha) are increased in clinical conditions where oxidative stress is suspected to play a pathogenic role. Moreover, isoPs have been detected in tissue extracts from atherosclerotic plaques and Alzheimer patients brain tissue. Finally, antioxidant treatments such as vitamin E supplementation appear to reduce isoPs levels in biological fluids of treated patients. These preliminary observations argue for a further investigation of isoPs as a practical pharmacodynamic endpoint for the clinical evaluation of antioxidant therapies.

Dietary lipid affects phospholipid fatty acid compositions, eicosanoid production and immune function in Atlantic salmon (Salmo salar).

Atlantic salmon (Salmo salar) post-smolts were fed diets containing either Fosol (FO), a North Sea fish oil, sunflower oil (SO), linseed oil (LO) or Marinol K (MO), a southern hemisphere fish oil rich in 20:5(n-3) for 12 weeks. A macrophage-enriched leucocyte preparation was obtained from head kidney and the fatty acid compositions of the individual membrane phospholipids measured. In general phospholipids from SO- and LO-fed fish had increased 18:2(n-6), 20:2(n-6) and 20:3(n-6) compared to the fish oil treatments while LO-fed fish had lower 20:4(n-6) than any other dietary treatment. Fish fed LO also had increased 18:3(n-3), 18:4(n-3), 20:3(n-3) and 20:4(n-3). The 20:5(n-3) content of kidney macrophage-enriched leucocyte phospholipids was highest in MO-fed fish followed by FO- and LO-fed fish with the lowest level in fish fed SO. The overall effect on the ratio of eicosanoid precursors, 20:4/20:5, showed the highest value in SO-fed fish and the lowest in fish fed LO. Production of LTB5 by kidney macrophage-enriched leucocytes stimulated with A23187 was highest in MO-fed fish and lowest in those fed SO. Production of LTB4 was greatest in SO-fed fish and lowest in fish fed LO. Serum Ig levels were significantly affected by dietary treatment with highest values in fish fed FO and SO and lowest in fish fed MO and LO.