scholarly journals Direct modulation of G-proteins by polyunsaturated fatty acids: a novel eicosanoid-independent regulatory mechanism in the developing lung

1997 ◽  
Vol 326 (3) ◽  
pp. 725-730 ◽  
Author(s):  
Somnath MUKHOPADHYAY ◽  
Sarah J. RAMMINGER ◽  
Mark McLAUGHLIN ◽  
Lorraine GAMBLING ◽  
Richard E. OLVER ◽  
...  

Basal and fatty-acid-modulated G-protein function was studied in 1–3-day-pre-term, fetal guinea-pig, type II (fATII) pneumocyte apical membrane. Unstimulated (tonic) high-affinity GTPase activity (measured as [γ-32P]GTP hydrolysis rate) was high and 77% pertussis toxin-insensitive. Alteration of this activity was used as a marker of G-protein regulation. Arachidonic acid (AA) showed a dose-dependent (IC50 = 48±8 μM) inhibition of activity at concentrations significantly below critical micellar concentrations; this effect was mimicked by other polyunsaturated fatty acids (IC50 for linoleic acid = 47±2 μM; IC50 for oleic acid= 106±11 μM). Saturated fatty acids showed no effect. The effect of AA on ouabain-insensitive ATPases in the same preparation was significantly lower, suggesting a specificity of the GTPase modulation effect. AA modulation of GTPase activity was not attenuated by blocking eicosanoid metabolism with inhibitors of 5′-lipoxygenase, cyclo-oxygenase and P-450. In order to explore further the mechanism of AA–G-protein interaction, the effect of AA on the time course and equilibrium binding of [35S]GTP[S] to apical membrane was studied. Consistent with our GTPase assay data, AA inhibited binding with an IC50 value of 71±1 μM; stearic acid did not mimic this effect. This is the first report of unsaturated-fatty-acid-specific modulation of lung G-protein function: since AA also up-regulates perinatal lung alveolar Na+ transport, we suggest this lipid/G-protein switch helps maintain pulmonary fluid homoeostasis around birth.

2000 ◽  
Vol 70 (1) ◽  
pp. 51-61 ◽  
Author(s):  
L. O. W. McClintont ◽  
A. F. Carson

AbstractThis study investigated the efficiency of growth and the carcass characteristics of 24 Greyface (Border Leicester × Scottish Blackface), 24 Texel (12 purebred and 12 Texel × Texel-Greyface) and 24 Rouge (12 purebred and 12 Rouge × Rouge-Greyface) lambs finished on the same level of feeding. The efficiency of live-weight gain (kg/MJ) was higher in Greyface compared with Texel lambs (P< 0·01). The efficiency of empty body-weight gain (kg/MJ) was higher in Greyface (P< 0·01) and Rouge (P< 0·05) compared with Texel lambs. The efficiency of carcass gains (kg/MJ) tended to be higher in Greyface and Rouge compared with Texel lambs (P= 0·07). The efficiency of non-carcass component gains (kg/MJ) was also higher in Greyface compared with Texel lambs (P0·05). Carcass water, protein, lipid and ash gains did not vary significantly between the genotypes, however carcass energy gain tended to be higher in Greyface and Rouge compared with Texel lambs (P= 0·08). The relative proportions of water, protein, lipid and ash in carcass gains did not vary significantly between the genotypes. At the end of the experiment carcass water content was higher in Texel compared with Greyface lambs (P< 0·05) and carcass ash content was lower in Texel compared with Greyface (P< 0·01) and Rouge (P< 0·05) lambs. The concentration of saturated fatty acids was higher in Greyface compared with Rouge lambs (P< 0·001) and higher in Rouge compared with Texel lambs (P< 0·05). Monounsaturated fatty acid concentrations were higher in Rouge compared with Greyface lambs (P< 0·05) and higher in Texel compared with Rouge lambs (P< 0·001). Polyunsaturated fatty acid concentrations were higher in Rouge and Texel compared with Greyface lambs (P< 0·01). The ratio of n-6:n-3 fatty acids was lower in Rouge compared with Greyface lambs (P< 0·05).The efficiency of empty body gain was higher in male compared with female lambs (P< 0·05). Carcass water (P< 0·01) and protein (P< 0·05) gains were higher in male lambs. At the end of the experiment male carcasses contained a higher content of water (P< 0·05), protein (P< 0·01) and ash (P= 0·07), and a lower lipid (P< 0·05) and energy (P< 0·001) content. Carcass lipids from male lambs contained a higher concentration of polyunsaturated fatty acids (P< 0·001) and tended to contain a lower concentration of saturated fatty acids (P = 0·06).


2010 ◽  
Vol 39 (10) ◽  
pp. 2297-2303 ◽  
Author(s):  
Daniele Cristina da Silva-Kazama ◽  
Geraldo Tadeu dos Santos ◽  
Paula Toshimi Matumoto Pintro ◽  
Jesuí Vergílio Visentainer ◽  
Ricardo Kazama ◽  
...  

Eight Holstein cows with body weight 570 ± 43 kg and 60 ± 20 lactation days were distributed in a double Latin square design with four 21-day periods to determine the effects of feeding ground or whole flaxseed with or without monensin supplementation (0.02% on a dry matter basis) on fatty acid profile of butter stored for 15 and 45 days. Ground flaxseed supply, in comparison to whole flaxseed, reduced relative percentages of 16:0, cis7-16:1, 17:0, and cis10-17:1 but it increased those of cis9,trans11-18:2, cis3-18:3, and omega 3 fatty acids in butter fat, reducing relative percentage of medium-chain fatty acids and increasing the content of polyunsaturated fatty acids. Supplementation with monensin increased relative percentages of cis9,trans11-18:2 and tended to increase relative percentage of 17:0 and decrease that of saturated fatty acids in butter. Butter from cows fed diet with monensin presented lower relative percentages of cis 6-20:4. Relative percentages of cis 9-16:1, cis10-17:1, 18:0, trans11-18:1, cis9-18:1, cis3-18:3, cis6-20:4 in butter stored for 15 days were higher than those stored for 45 days and the relative percentages of cis3-20:5 tended to decrease with the increase of storage period. As a result, relative percentages of saturated fatty acids and medium-chain fatty acids increased with storage time, while those of monounsaturated and long-chain fatty acids decreased. Butter enriched with polyunsaturated fatty acids may have a shorter shelf life due to the negative effect of storage on fatty acid profile which may cause oxidation and rancidity.


2021 ◽  
Vol 14 (1) ◽  
pp. 11-22
Author(s):  
Prasetyo Nugroho ◽  
Komang Gede Wiryawan ◽  
Dewi Apri Astuti ◽  
Wasmen Manalu

Background and Aim: Flushing with the manipulation of fatty acids, particularly polyunsaturated fatty acids, like linoleic and α-linolenic acids in the ration, is a strategy to raise the nutritional status of the female mammals to improve ovarian function and follicle development. This study was designed to investigate the effectiveness of flushing supplementation with different types of polyunsaturated and saturated fatty acids in stimulating follicle growth and development during estrus in Ettawa Grade does with a low initial body condition score (BCS ≤2). Materials and Methods: Eighteen Ettawa Grade does in the second parity, with an average body weight of 32.11±2.19 kg, were divided into three groups according to the fatty acid supplemented to their ration: (i) About 2.8% lauric acid flushing (group); (ii) 2.8% linoleic acid flushing (LA group); and (iii) 2.8% a-linolenic acid flushing (ALA group). The ration was formulated to be isocaloric (total digestible nutrient = 77%) and isonitrogenous (crude protein = 15%). The experiment was conducted for 35 days; that is, 14 days for acclimatization and synchronization of the estrous cycle and 21 days for fatty acid flushing until the appearance of the next estrus. A completely randomized design was applied. Results: According to the results, none of the different fatty acids in the ration affected the nutrient intakes, BCSs, average daily gains, and plasma glucose, cholesterol, and progesterone concentrations of the three groups of does. However, the BCSs (by 0.8-0.9) and the plasma cholesterol concentrations were higher after fatty acid flushing for 21 days than before the flushing period. The ALA group had the highest number of large-sized preovulatory follicles, whereas the LAURIC group had the highest plasma estradiol concentration during estrus. All three groups had similar plasma progesterone concentrations during estrus after fatty acid flushing. Conclusion: Flushing supplementation with 2.8% ALA from flaxseed oil gave the best results in terms of stimulating the highest number of large-sized preovulatory follicles in Ettawa Grade does.


2011 ◽  
Vol 57 (6) ◽  
pp. 604-614 ◽  
Author(s):  
T.A. Misharina ◽  
E.B. Burlakova ◽  
L.D. Fatkullina ◽  
M.B. Terenina ◽  
N.I. Krikunova ◽  
...  

Age-related alterations of fatty acid composition in liver and brain of AKR mice was investigated. The effect of savory essential oil (Satureja hortensis L.), added with drinking water on fatty acid composition in these organs and the processes of lipid peroxidation in erythrocytes were estimated. It was found that during aging the percentage of saturated fatty acids and polyunsaturated fatty acids decreased while monounsaturated fatty acids increased. The development of leukemia was accompanied by the increase of saturated and polyunsaturated fatty acids percentage and a decrease of monounsaturated fatty acids amount. In the liver aging caused the increase in the percentage of saturated fatty acids, the decrease of monounsaturated fatty acids, while the amount of polyunsaturated fatty acids was not changed. Leukemia (after 8 month) was accompanied by the increase of percentage of monounsaturated fatty acids and the decrease in the amount of oleinic and docosohexaenic acids. The intake of savory essential oil was accompanied by intensification of polyunsaturated fatty acids synthesis in mice liver and reduction of lipid peroxidation products content.


2000 ◽  
Vol 84 (1) ◽  
pp. 103-109 ◽  
Author(s):  
Franca Marangoni ◽  
Carlo Agostoni ◽  
Anna M. Lammard ◽  
Marcello Giovannini ◽  
Claudio Galli ◽  
...  

While a wealth of data on the fatty acid composition of mature human milk has been published, limited information is available on the quantities of individual fatty acids supplied to the suckling infant with maternal milk, through the whole first year of life. Our aim was to qualitatively and quantitatively evaluate the fatty acid composition of human milk from Italian mothers, throughout extended lactation with particular emphasis on the long-chain polyunsaturated fatty acids. We have thus measured the total fat content and the concentrations of major fatty acids by quantitative GLC in pooled breast hindmilk collected from all feedings over 24 h at colostrum, 1, 3, 6, 9 and 12 months in ten mothers recruited after delivery of full-term infants. Total saturated fatty acids progressively increase and total monounsaturated progressively decrease as percentage levels, while among long-chain polyunsaturated fatty acids, percentages of arachidonic acid and docosahexaenoic acid decrease from colostrum up to the third month. Hindmilk total lipids (mg/dl) rise more than twofold up to 3 months, and then remain stable. The amounts (mg/dl) of linoleic acid and α-linolenic acid progressively increase, following the trend of total fat, while arachidonic and docosahexaenoic concentrations (mg/dl) remain stable throughout the whole nursing period. Assessment of the intakes per kg body weight shows different trends for the individual major long-chain polyunsaturated fatty acids supplied to the infant from hindmilk during exclusive breast-feeding (3 months). This information may be useful for the evaluation of infant intakes during extended lactation.


2002 ◽  
Vol 2002 ◽  
pp. 178-178
Author(s):  
M. Enser ◽  
N. Scollan ◽  
S. Gulati ◽  
G. Nute ◽  
K. Hallett ◽  
...  

Recommendations to improve the UK diet suggest an increase in the ratio of polyunsaturated to saturated fatty acids (P:S ratio) and a higher consumption of n-3 polyunsaturated fatty acids (PUFA). Ruminant meats have a poor P:S ratio, approximately 0.1 compared to the recommendation of 0.4-1.0 for the whole diet. However, the ratio of C18:2 n-6/C18:3 n-3 (the n-6:n-3) is well within the recommended value of <4.0 at approximately 2 and ruminant muscle also supplies longer-chain n-3 PUFA. By feeding lipid in a formaldehyde cross-linked protein matrix, rumen biohydrogenation can be avoided and the tissue PUFA level increased but with potential effects on oxidative shelf-life, colour and flavour of the meat. This trial investigated the fatty acid composition and quality of meat produced by feeding a protected lipid supplement (PLS).


Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 537
Author(s):  
Silvia Cetrullo ◽  
Stefania D’Adamo ◽  
Veronica Panichi ◽  
Rosa Maria Borzì ◽  
Carla Pignatti ◽  
...  

While high levels of saturated fatty acids are associated with impairment of cardiovascular functions, n-3 polyunsaturated fatty acids (PUFAs) have been shown to exert protective effects. However the molecular mechanisms underlying this evidence are not completely understood. In the present study we have used rat H9c2 ventricular cardiomyoblasts as a cellular model of lipotoxicity to highlight the effects of palmitate, a saturated fatty acid, on genetic and epigenetic modulation of fatty acid metabolism and fate, and the ability of PUFAs, eicosapentaenoic acid, and docosahexaenoic acid, to contrast the actions that may contribute to cardiac dysfunction and remodeling. Treatment with a high dose of palmitate provoked mitochondrial depolarization, apoptosis, and hypertrophy of cardiomyoblasts. Palmitate also enhanced the mRNA levels of sterol regulatory element-binding proteins (SREBPs), a family of master transcription factors for lipogenesis, and it favored the expression of genes encoding key enzymes that metabolically activate palmitate and commit it to biosynthetic pathways. Moreover, miR-33a, a highly conserved microRNA embedded in an intronic sequence of the SREBP2 gene, was co-expressed with the SREBP2 messenger, while its target carnitine palmitoyltransferase-1b was down-regulated. Manipulation of the levels of miR-33a and SREBPs allowed us to understand their involvement in cell death and hypertrophy. The simultaneous addition of PUFAs prevented the effects of palmitate and protected H9c2 cells. These results may have implications for the control of cardiac metabolism and dysfunction, particularly in relation to dietary habits and the quality of fatty acid intake.


Author(s):  
Martin Benzler ◽  
Jonas Benzler ◽  
Sigrid Stoehr ◽  
Cindy Hempp ◽  
Mohammed Z. Rizwan ◽  
...  

Saturated fatty acids are implicated in the development of metabolic diseases, including obesity and type 2 diabetes. There is evidence, however, that polyunsaturated fatty acids can counteract the pathogenic effects of saturated fatty acids. To gain insight into the early molecular mechanisms by which fatty acids influence hypothalamic inflammation and insulin resistance, we performed time-course experiments in a hypothalamic cell line, using different durations of treatment with the saturated fatty acid palmitate, and the omega-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA). Western blot analysis revealed that palmitate elevated the protein levels of phospho(p)AKT in a time-dependent manner. This effect seems involved in the pathogenicity of palmitate, as temporary inhibition of the PI3K/AKT pathway by selective PI3K inhibitors prevented palmitate-induced insulin resistance. Similarly to palmitate, DHA also increased levels of pAKT, but to a weaker extent. Co-administration of DHA with palmitate decreased pAKT close to the basal level after 8 h, and prevented palmitate-induced insulin resistance after 12 h. Measurement of the inflammatory markers pJNK and pNF&kappa;B-p65 revealed tonic elevation of both markers in the presence of palmitate alone. DHA alone transiently induced elevation of pJNK, returning to basal levels by 12 h treatment. Co-administration of DHA with palmitate prevented palmitate-induced inflammation after 12 h, but not at earlier time points.


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