Search results for "FATTY ACID"
showing 10 items of 1141 documents
Psychosocial stress, catecholamines, and essential fatty acid metabolism in rats.
1994
To examine the effects of psychosocial stress and the "stress hormone," epinephrine, on essential fatty acid metabolism in rats, two studies were conducted. In the first, the effects of four weeks of (i) social isolation and (ii) group housing (control) on liver microsomal delta 6 and delta 5 n-6 desaturase activity were studied in group-reared male normotensive (Wistar Kyoto) and spontaneously hypertensive (SHR) rats (n = 5/group). The second study examined the effects of acute ip epinephrine (0.0, 1.0, 2.0, and 4.0 mg/kg) 6 hr prior to and following an ig dose (4 g/kg) of safflower oil (rich in 18:2n-6, LA) on plasma and liver LA, 20:4n-6 (AA), and LA/AA ratios in adult essential fatty ac…
Liver fatty acid composition in the spontaneously diabetic BB rat.
1991
The purpose of the present experiment was to investigate if the modulation by insulin of liver microsomal desaturase activities in the spontaneously diabetic adult male Bio-Breeding (BB) rat, with destructive insulitis resembling the lesions described in the human Type I (insulin-dependent) diabetes, corresponds to modifications in fatty acid composition, reflect of changes in fatty acid desaturation. We observed no significant differences between BB rats, during the hyper-(48 h), the normo-(17 h) and the hypo-glycemic (3 h) periods which followed the insulin injection, and control rats for the fatty acid composition of liver total lipids, phosphatidylethanolamines, phosphatidylcholines, tr…
Fatty acid metabolism, pharmacological nutrients and hypertension.
1997
Abstract The purpose of the present study was to investigate the effect of a concentrated preparation (EPA30) containing eicosapentaenoic acid (EPA. 20:5 n -3) and docosahexaenoic acid (DHA, 22:6 n -3) on the limiting desaturation steps of the polyunsaturated fatty acid biosynthesis in spontaneously hypertensive rats (SHR). Adult SHR were divided into two groups: one group received a standard diet, and the experimental group the standard diet including 0.8% of EPA30 for 9 weeks. Blood pressure was measured at the end of the diets. The desaturase activities and fatty acid composition were determined in isolated hepatocytes. The blood pressure did not decrease in the experimental group. The d…
Depletion of delta 9 desaturase (EC 1.14.99.5) activity in lactating rat during protein restriction.
2000
The effects of protein restriction on the activity of delta9 desaturase (EC 1.14.99.5) were investigated in lactating rats. A control group was fed a balanced diet (20% casein) for 14 days, whereas the experimental groups were fed a low-protein diet (8% casein), supplemented with or without L-methionine (0.4%), for 14 days. The enzyme activity was measured by incubations of hepatic microsomal pellets with (1-14C) stearic acid. Results showed a decreased delta9 desaturase activity, after 2,7 and 14 days of depleted diet, of -50, -40 and -33% respectively, compared with control. The supplementation of the low-protein diet with 0.4% methionine, which favours food consumption as well as growth,…
Influence of spontaneous hypertension on n-3 delta-6-desaturase activity and fatty acid composition of rat hepatocytes.
1995
The first and rate limiting step in the conversion of alpha-linolenic acid is catalyzed by the delta-6-desaturase enzyme. The activity of such an enzyme was studied in order to investigate the n-3 Polyunsaturated Fatty Acid biogenesis during hypertension. Rat isolated hepatocyte n-3 delta-6-desaturase activity was higher in 1 month old Spontaneously Hypertensive Rats — prehypertensive period- as compared to normotensive Wistar Kyoto rats, whereas there was no significant difference at 12 months — hypertensive period-. Our data indicate no correlation between the directly measured enzyme activity and the changes in hepatocyte n-3 fatty acid compositions. The loss of hepatocyte n-3 delta-6-de…
Desaturation and esterification of fatty acids in kidney cells from spontaneously hypertensive rats
2001
In previous studies, several alterations in lipid metabolism have been related to hypertension, but the mechanisms explaining this relationship have not been elucidated. None of the previous works has focused on the lipid metabolism in kidney, which is a key organ in the overall regulation of blood pressure. The aim of the present work was to study the metabolism of polyunsaturated fatty acids, and the possible compositional changes in kidney from hypertensive rats. Radiolabelled linoleic acid (18:2,n-6) and dihomogammalinolenic acid (20:3, n-6) were incubated with isolated kidney cells from spontaneously hypertensive rats (SHR) or the parent normotensive strain (Wistar Kyoto, WKY). The rat…
Altered desaturase activities and fatty acid composition in liver microsomes of spontaneously diabetic Wistar BB rat.
1992
We examined the activities of delta 9, delta 6 and delta 5 desaturases and fatty acid composition of liver microsomes in the insulin-dependent spontaneously diabetic adult female Wistar Bio-Breeding (BB) rat. The diabetic BB rats were subcutaneously injected with different doses of protamine zinc insulin in order to be killed in hyper-, normo- or hypo-glycemic states. Desaturase activities, which are partially inhibited by spontaneous diabetes during the normo- and hyper-glycemic periods, were similarly affected by the various insulin treatment; delta 9 desaturase activity being more depressed than the desaturase activities of either delta 6 of delta 5. Insulin treatment with 10 I.U./kg bod…
Phospholipid fatty acids in anthers of eggplant (S.melogena), allied species and correspondent introgression lines
2009
In Vitro Bioactivity of Astaxanthin and Peptides from Hydrolisates of Shrimp (Parapenaeus longirostris) By-Products: From the Extraction Process to B…
2021
Non-edible parts of crustaceans could be a rich source of valuable bioactive compounds such as the carotenoid astaxanthin and peptides, which have well-recognized beneficial effects. These compounds are widely used in nutraceuticals and pharmaceuticals, and their market is rapidly growing, suggesting the need to find alternative sources. The aim of this work was to set up a pilot-scale protocol for the reutilization of by-products of processed shrimp, in order to address the utilization of this valuable biomass for nutraceutical and pharmaceuticals application, through the extraction of astaxanthin-enriched oil and antioxidant-rich protein hydrolysates. Astaxanthin (AST) was obtained using …
Seminal plasma biochemistry and spermatozoa characteristics of Atlantic cod (Gadus morhua L.) of wild and cultivated origin
2011
Abstract Our objectives were to compare spermatozoa activity, morphology, and seminal plasma (SP) biochemistry between wild and cultivated Atlantic cod ( Gadus morhua ). Swimming velocities of wild cod spermatozoa were significantly faster than those of cultivated males. Wild males had a significantly larger spermatozoa head area, perimeter, and length, while cultivated males had more circular heads. Total monounsaturated fatty acids and the ratio of n−3/n−6 were significantly higher in sperm from wild males, while total n−6 from cultivated males was significantly higher than the wild males. Significantly higher concentrations of the fatty acids C14:0, C16:1n−7, C18:4n−3, C20:1n−11, C20:1n−…