On the allometric scaling of fatty acids in the phospholipids of metabolically active fowl tissues

In our recent studies domesticated fowl species in the range from 150 g (Japanese quail, Coturnix coturnix japonica) to 19 kg (turkey, Meleagris gallopavo) were analysed, to elucidate supposed allometric relationship of the membrane lipid fatty acids (FA). The basis of all studies was the „membranes as pacemakers of metabolism” by Hulbert (Lipids, 2007, 42, 811-819). First in the myocardium (B=-0.6), later in the avian kidney (-0.18) and lung (-0.24), as well as liver (-0.2) negative allometric scaling was found for docosahexaenoic acid (DHA). In the membrane FAs of all these tissues rather balanced polyunsaturation, negatively scaling n3 and unsaturation index and oppositely related n6 and monounsaturated FA molar proportions were described. In the lavaged avian lung surfactant phopsholipids we reported similar negative allometry for DHA. In contarst, avian brain phospholipid FA composition failed to provide body mass relation. We found unexpected results (positive allometry for n3 FAs, DHA, unsaturation index) in the m. pectoralis superficialis phospholipids during turkey ontogenesis. In all the aforementioned splanchnic organs the concentration of whole tissue malondialdehyde was also negatively related to body mass (B=-0.16, -0.05, -0.17, -0,13 in the heart, lung, kidney and liver). Results indicate a special regulatory role for DHA, in agreement with the membrane pacemaker theory, while suggest also a strong predispository and linking role for this acid and the polyunsaturated n3 FAs towards non enzymatic lipid peroxidation

Effect of short-term aflatoxin exposure in combination with medicinal herb mixture on lipid peroxidation and glutathione redox system in laying hens

Aflatoxins are well known hepatotoxic mycotoxins, which mainly contaminate the cereal grains. Those induce lipid peroxidation and impair the antioxidant, including glutathione redox system in long-term studies. The purpose of present study was to investigate the short-term (36-hour) effect of feeding aflatoxin B1 (AFB1) contaminated diet alone or in combination with a medicinal herb mixture on lipid peroxidation (conjugated dienes and trienes, and malondialdehyde), and on parameters of the glutathione system (reduced glutathione and glutathione peroxidase) in blood plasma, red blood cell haemolysate, liver and kidney homogenate of 49-week old Bovans Goldline laying hens. The results revealed that AFB1 (125 m /kg feed) did not have effect on feed intake, body and liver weight, but increased malondialdehyde content was observed in blood plasma and red blood cell haemolysate as effect of feeding AFB1 and medicinal herb mixture at 36th hour of the trial. However, the same diet resulted in lower malondialdehyde content in liver, but not in kidney. Reduced glutathione concentrations showed variance among treatments; thus due to inclusion of medicinal herb mixture in the diet lower values were measured in red blood cell haemolysate. Glutathione peroxidase activity was significantly lower in all treated groups as compared to the control at 36th hour of the trial in blood plasma, but not in other tissues. The results are contradictory with previous findings, probably due to the short-term exposure, and/or to medicinal herb mixture supplementation as it could moderately modify the effect of AFB1

The effects of excessive starvation on antioxidant defence and lipid peroxidation in intensively reared, commercial-size pikeperch (Sander lucioperca L.)

The present study investigated the influence of various lengths of starving periods on lipid peroxidation and on parameters of the glutathione redox system – as reduced glutathione (GSH) concentration and glutathione peroxidase (GPx) activity – in meat and liver of commercial-size pikeperch. Forty cultured, market size (average body weight: 732.2 ± 129.8 g), mixed sex pikeperch were divided into 5 groups (n = 8 in each), where the experimental groups were withdrawn from feed for 3 and 6 weeks. After respective periods, fish were slaughtered immediately. Increasing the length of the starving period reduced the body weight, mainly due to losses in intraperitoneal and intramuscular fat. Due to starvation, higher rate of lipid peroxidation was found, as measured by the significantly higher malondialdehyde (MDA) concentration in the liver (36.59 ± 11.11 vs. 17.90 ± 3.13 μmol/g wet weight) and meat (35.25 ± 6.28 vs. 26.99 ± 9.60 μmol/g wet weight), which was probably caused by the impairment of the glutathione redox system. Lower GSH concentration (1.42 ± 0.32 vs. 2.81 ± 0.32 µmol/g protein) and GPx activity (1.53 ± 0.38 vs. 2.59 ± 0.35 U/g protein) were also found in liver. The results indicate that long-term starvation impaired the amount and/or activity of glutathione redox system, and consequently increased the rate of lipid peroxidation in pikeperch. Keywords: Antioxidant defence, Lipid peroxidation, Pikeperch, Starvation, Glutathione, Malondialdehyd

Negative allometry of docosahexaenoic acid in the fowl lung and pulmonary surfactant phospholipids

In a recent study (Comp. Biochem. Physiol. B. (2010)155: 301–308) we reported that the fatty acids (FA) of the avian (7 species) total lung phospholipids (PL) (i.e. lung parenchyma and surfactant together) provide allometric properties. To test whether this allometric scaling also occurs in either of the above components, in six gallinaceous species, in a body weight range from 150 g (Japanese quail, Coturnix coturnix japonica) to 19 kg (turkey, Meleagris gallopavo) the PL FA composition (mol%) was determined in the pulmonary surfactant, in native and in thoroughly lavaged lungs (referred to as lung parenchyma). In all three components docosahexaenoic acid (DHA) showed significant and negative allometric scaling (B = –0.056, –0.17 and –0.1, respectively). Surfactant PLs provided further negative allometry for palmitic acid and the opposite was found for palmitoleate and arachidonate. In the lung parenchymal PLs increasing body weight was matched with shorter chain FAs (average FA chain length) and competing n6 and n3 end-product fatty acids (positive allometry for arachidonic acid and negative for DHA). Negative allometric scaling was found for the tissue malondialdehyde concentration in the native and lavaged lungs (B = –0.1582 and –0.1594, respectively). In these tissues strong correlation was found between the MDA concentration and DHA proportion (r = 0.439 and 0.679, respectively), denoting the role of DHA in shaping the allometric properties and influencing the extent of in vivo lipid peroxidation of membrane lipids in fowl lungs