Feeding experiments with selected fatty acid Feeding experiments - PowerPoint PPT Presentation

Feeding experiments with selected fatty acid Feeding experiments with selected fatty acid supplementations supplementations EU IPA project – – ID: HUSRB/1002/214/120 ID: HUSRB/1002/214/120 EU IPA project Istvan Csengeri, PhD Research Institute for Fisheries, Aquaculture and Irrigation (HAKI) Szarvas, Hungary e-mail: csengeri@haki.hu

Introduction

BACKGROUND OF EU IPA-HUSRB PROJECT Hungary and Serbia are similar countries in respect of fish production and fish production capacity, in fish consumption and in cardiovascular disease (CVD) mortality rates. In both countries Common carp ( Cyprinus carpio ) is the main cultured fish comprising to 70 to 80% of the total domestic fish production (Pintér, 2009; FAO, 2011 ). The per capita fish consumption was 5.2 kg in 2006 in Serbia (FAO, 2011) and approx 6.0 kg in live weight in Hungary (4.16 kg fish meat per capita in 2008 in Hungary - Pintér,2009), being among the lowest in Europe. The CVD mortalities are over 50% in both countries (Knezevic & Grozdanov, 2009; Bényi, 2008). Our objectives: TO DEVELOP such MODERN FEEDS for CARP which can help to IMPROVE HEALTH CONDITION through CONSUMPTION OF INCREASED QUALITY FISH MEAT .

Role of omega-3 polyenoic fatty acids in human nutrition Several papers show that the CVD mortalities can be decreased by consuming fish rich in long chain polyunsaturated fatty acids (LcPUFA) belonging to omega-3 family. Polyunsaturated fatty acids of linoleic and linolenic acid family are regarded as essential nutrients, that is, they have to be supplied in the food. Essential fatty acids (EFA) are basically of plant origin. Main fatty acid series /families/ ω 7-series palmitoleic (n-7) 16 :1(n-7) ω 9-series oleic (n-9) 18 :1(n-9) ω 6-series linoleic (n-6) 18 :2(n-6) ω 3-series linolenic (n-3) 18 :3(n-3)

EFA – newer results

Membrane microdomains Association of proteins can be induced by selective accumulation of proteins in distinct lipid microdomains (a) or by specific protein–protein interactions (b). (a) The membrane contains lipid microdomains with distinct lipid compositions. These membrane areas harbor different sets of proteins. Green lipid molecules preferentially accumulate proteins whose transmembrane domain is displayed in black and also proteins that are attached to the extracellular leaflet of the membrane (glycosylphosphatidylinositol-anchored proteins). The mechanism for the selective accumulation of proteins in a given lipid environment can be explained by a preference of proteins for the chemical (hydrophobicity) or physical (membrane thickness, microviscosity) properties of the lipid microdomain. Nanometer-sized protein associations can be considered a lipid-mediated interaction in this case. (b) (b) Specific protein–protein interactions mediated by transmembrane proteins or ligands binding to them also may be responsible for the generation of protein associations . Source: Vereb et al. 2003. PNAS, 100 (14) 8053-8058

Modifications of membrane composition with increased eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake. When EPA and DHA (n-3 PUFAs) become incorporated into membranes, they affect the properties of both lipid rafts (left) and caveolae (right), reducing the sphingomyelin content of the former and the cholesterol and caveolin content of the latter. These changes can influence the function and binding of membrane associated proteins, ultimately altering cell function. Source: W.S. Harris, 2008. The omega-3 index as a risk factor for coronary heart disease. Am J Clin Nutr 2008; 87(suppl):1997S–2002S citing from MA et al., 2004. n–3PUFAand membrane microdomains: a new frontier in bioactive lipid research. J Nutr Biochem 15:700-6.

Newer functions of the Omega-3 Fatty acids Modified from: Serhan, C.N. 2010. Resolvins and Protectins: Specialized Pro-Resolving Mediators in Inflammation and Organ Protection: Metabolomics of Catabasis. NUTRITION, TRAUMA, AND THE BRAIN, Prepublication copy: Uncorrected proofs

The Omega-3 index The omega-3 index is the sum of 2 prominent long- chain n-3 fatty acids [ ie , eicosapentaenoic acid (EPA) and docosahexaenoic acids (DHA)] in erythrocyte membranes and is expressed as a percentage of total erythrocyte fatty acids (FAs). Source: W.S. Harris, C. von Schacky 2004. The Omega-3 Index: a new risk factor for death from coronary heart disease? Preventive Med., 39:212-220

The Omega-3 index Source: Sala-Vila A, Harris WS, Cofán M, Pérez-Heras AM, Pintó X, Lamuela-Raventós RM, Covas MI, Estruch R, Ros E. 2011. Determinants of the omega-3 index in a Mediterranean population at increased risk for CHD. British J Nutrition 106(3):425-31.

Increased blood levels of the omega-3 fatty acids (FA) – EPA and DHA have been inversely associated with risk for sudden cardiac death - Low EPA+DHA may be associated with increased risk for ACS Acute coronary syndrome (ACS) is usually one of three diseases involving the coronary arteries: ST elevation myocardial infarction (30%), non ST elevation myocardial infarction (25%), or unstable angina (38%). 1 Source: Block RC, Harris WS, Reid KJ, Sands SA, Spertus JA. 2008. EPA and DHA in blood cell membranes from acute coronary syndrome patients and controls. Atherosclerosis.197(2):821-8.

Planned dietary experiments

Planned feeds for carp experiments Activity 1: Development of fish feed formulations trials Four new diets for carp, with superior nutritional and physical characteristics, will be formulated. While control feed will be a commercial sinking pellet , four new formulations will be developed to produce floating feed containing different combinations of raw feed materials, linseed and fish oils, as well as specific ingredients such as arachidonic acid (ARA) rich oil and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) fortified oil. FEEDS : commercial sinking pellet (control – C1): 90 kg floating diets: (i) linseed oil diet (4 % LSO – F1); - 60 kg (ii) LSO plus arachidonic acid, ARA-rich oil (from fungus Mortierella alpina), (LSO 2% + 2% ARA(>40%) - F2); 30 kg (iii), fish oil diet (Fish oil 4 % - F3); 30 kg (iv) PUFA restoration floating diet (F4) - 60 kg (iv)? (Fish oil 2 % +1.4% ARA + 0.6 % DHA - F4) (v)? (Fish oil 2 % +1.0% ARA + 0.5 % EPA + 0.5 % DHA – F5) Oil addition depends on the available ingredients’ fat contents.

Planned experiments with carp Activity 4: Feed performance in fish feeding trials Feed efficiency of new four feeds will be tested in feeding trial with common carp (~ 0.5 kg) in in-door tank culture system to produce edible size (>1 kg) carp. In the 1st trial, one commercial sinking diet and three floating diets - containing LNA, ARA, EPA and DHA - will be fed for 2-month period. In the 2nd trial, fish will be fed a commercial sinking diet and the fourth floating diet for 6 weeks. During experiments, oxygen levels will be monitored daily and other water quality parameters will be measured weekly. The fish performance parameters will be evaluated at the end of experiments. 1st carp trial C1 - sinking pellet ( control – C1 ); 60 kg F1 - linseed oil diet ( 4 % LSO – F1 ); 30 kg F2 - LSO plus arachidonic acid, ( LSO 2% + 2% ARA - F2 ); 30 kg F3 - fish oil diet ( Fish oil 4 % - F3 ); 30 kg F4 - PUFA restoration floating diet ( Fish oil 2 % +1.5% ARA + 0.5 % DHA- F4 ); 30 kg 2nd carp trial C1 - sinking pellet ( control – C1 ): 30 kg C1-F4 - sinking pellet group continued on + PUFA restoration floating diet; 30 kg

Planned experiments with carp Activity 5: Fish meat quality - chemical assessment At the end of the feeding trials, fish fillets will be separated by standard slaughter technique. The fish meat chemical analyses of homogenized fillets (in total 36 samples from both feeding trials) will include basic chemical composition and fatty acid profile.

Planned experiments with mammalian model - feeding on carp meat Activity 6: Fish meat quality - biological assessment Fish fillet portions from the feeding trials will be included into diets for 2 feeding trials with mammalian model animals, i.e. rats. After feeding trials, specific physiological effects, which can appear in humans as a consequence of nutrition, will be determined and evaluated. The weight gain, blood pressure, heart rate and ex vivo platelet aggregation changes of rats, fed a carp-extract enriched food, will be recorded. Further, the effects of carp-extract feeding in rats on myocardial ischemia - reperfusion induced arrhythmias, will be determined. Rat feeding trial A. RChow - control group on rat chow diet RcarpF1 – solid diet plus/or with carp fillet (from fish reared on linseed oil diet (4 % LSO – F1) RcarpF2 - solid diet plus/or with carp fillet (from fish reared on LSO plus arachidonic acid diet (LSO 2% + 2% ARA - F2) Rat feeding trial B. RcarpF3 – solid diet plus/or with carp fillet (from fish reared on fish oil diet (Fish oil 4 % - F3) RcarpF4 - solid diet plus/or with carp fillet (from fish reared on PUFA restoration floating diet (Fish oil 2% +1.5% ARA + 0.5% DHA- F4)

Why to include ARA, EPA & DHA into experimental feeds of carp ? Carp meat with special quality and/or as functional food for mothers and/or infants ?

Review on the Long-Chain Omega-3 Oils–An Update on Sustainable Sources by Peter D. Nichols, James Petrie and Surinder Singh Nutrients 2010, 2, 572-585; doi:10.3390/nu2060572