Technical note: Comparative evaluation of 3 methods for the quantification of nonesterified fatty acids in bovine plasma sampled prepartum

Fatty liver is closely associated with elevated concentrations of nonesterified fatty acids (NEFA) and a low level of very low-density lipoproteins (VLDL) in blood of dairy cows. High NEFA inhibit the VLDL synthesis and assembly, and cause hepatic triacylglycerol (TAG) deposition. Sirtuin 3 (SIRT3), a mitochondrial deacetylase, antagonizes NEFA-induced TAG accumulation through modulating expressions of fatty acid synthesis and oxidation genes in cow hepatocytes. However, the role of SIRT3 in the VLDL synthesis and assembly was largely unknown. Here we aimed to test whether SIRT3 would recover the synthesis and assembly of VLDL in cow hepatocytes induced by high NEFA. Primary cow hepatocytes were isolated from 3 Holstein cows. Hepatocytes were infected with SIRT3 overexpression adenovirus (Ad-SIRT3), SIRT3-short interfering (si) RNA, or first infected with Ad-SIRT3 and then incubated with 1.0 mM NEFA (Ad-SIRT3 + NEFA). Expressions of key genes in VLDL synthesis and the VLDL contents in cell culture supernatants were measured. SIRT3 overexpression significantly increased the mRNA abundance of microsomal triglyceride transfer protein (MTP), apolipoprotein B100 (ApoB100) and ApoE (p < 0.01), and raised VLDL contents in the supernatants (p < 0.01). However, SIRT3 silencing displayed a reverse effect in comparison to SIRT3 overexpression. Compared with NEFA treatment alone, the Ad-SIRT3 + NEFA significantly upregulated the mRNA abundance of MTP, ApoB100 and ApoE (p < 0.01), and increased VLDL contents in the supernatants (p < 0.01). Our data demonstrated that SIRT3 restored the synthesis and assembly of VLDL in cow hepatocytes challenged with NEFA, providing an in vitro basis for further investigations testing its feasibility against hepatic TAG accumulation in dairy cows during the perinatal period.

Download Full-text

Comment on: Nonesterified fatty acids and risks of frailty, disability, and mobility limitation in older adults: The cardiovascular health study

Journal of the American Geriatrics Society ◽

10.1111/jgs.17129 ◽

2021 ◽

Author(s):

Mehmet Ilkin Naharci ◽

Ilker Tasci

Keyword(s):

Older Adults ◽

Fatty Acids ◽

Cardiovascular Health ◽

Mobility Limitation ◽

Health Study ◽

Cardiovascular Health Study ◽

Nonesterified Fatty Acids

Download Full-text

Seasonal Variation in Plasma Nonesterified Fatty Acids of Lake Sturgeon (Acipenser fulvescens) in the Vicinity of Hydroelectric Facilities

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f93-268 ◽

1993 ◽

Vol 50 (11) ◽

pp. 2440-2447 ◽

Cited By ~ 15

Author(s):

R. S. McKinley ◽

T. D. Singer ◽

J. S. Ballantyne ◽

G. Power

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Lake Sturgeon ◽

Acipenser Fulvescens ◽

Total Plasma ◽

Nefa Concentration ◽

Plasma Nefa ◽

Nonesterified Fatty Acids ◽

Plasma Nefa Concentration ◽

Fatty Acid Species

To establish the effects of hydroelectric generation on the health of lake sturgeon (Acipenser fulvescens), seasonal variations in plasma nonesterified fatty acids (NEFAs) upstream and downstream from hydroelectric stations were measured over a 2-yr period. Plasma NEFA profiles were also compared up- and downstream of the stations for differences in utilization of individual NEFA species as substrates for lipid oxidation. Significantly higher levels of total plasma NEFA were found in lake sturgeon upstream (2355 ± 395.9 nmol/mL) compared with those downstream (798 ± 133.5 nmol/mL) of the generating stations during the spring. The NEFA profiles for several key fatty acid species differed significantly among seasons up- and downstream of the facilities. In particular, during spring and summer, the levels of oleic acid (18:1n9) were highest upstream of the stations and levels of a polyunsaturated fatty acid, docosahexaenoic acid (22:6n3), were higher below rather than above the stations. The differences in plasma NEFA concentration may be attributed to altered nutritional status due to the varying flow regime located downstream of the hydroelectric stations.

Download Full-text

Effect of time of supplementary feeding on intake, apparent digestibility and rumen fermentation of grass hay by sheep

Animal Science ◽

10.1017/s0003356100007704 ◽

1994 ◽

Vol 59 (2) ◽

pp. 217-222 ◽

Cited By ~ 2

Author(s):

M. D. Carro ◽

A. R. Mantecón ◽

I. A. Wright ◽

I. J. Gordon

Keyword(s):

Fatty Acids ◽

Volatile Fatty Acids ◽

Plasma Concentrations ◽

Rumen Fermentation ◽

Apparent Digestibility ◽

Nonesterified Fatty Acids ◽

Rumen Ph ◽

Grass Hay ◽

Forage Intake ◽

Male Sheep

AbstractEffects of time of supplementation on forage intake, nutrient apparent digestibility and rumen fermentation were studied with 12 mature castrated male sheep (wethers) offered grass hay from 16.30 h to 09.30 h and supplemented with a cereal-based concentrate given at either 09.30 or 16.00 h. Voluntary intake of hay organic matter (OM) was decreased by feeding the concentrate (P< 0·01). Offering concentrate at 09.30 h after hay was available, increased intake of hay and total OM compared with offering it at 16.00 h before hay was available (P< 0·05). Daily pattern of hay intake was not changed when concentrate was offered at 09.30 h compared with feeding hay alone, but concentrate given at 16.00 h resulted in a lower hay intake between 16.30 and 18.00 h. Sheep offered concentrate at 09.30 h had higher rumen ammonia levels than those offered concentrate at 16.00 h, but there were no differences in the apparent digestibility of the nutrients, rumen pH and molar proportions of the main volatile fatty acids. There were also no differences between groups in the blood plasma concentrations of 3-hydroxybutyrate (30HB), nonesterified fatty acids (NEFA) and glucose. It is concluded that feeding supplement after rather than before a period of intake of forage or a bout of grazing may offer a means of minimizing reduction of forage intake as a consequence of feeding concentrate.

Download Full-text

STRUCTURE-FUNCTION RELATIONSHIPS IN THE ADIPOSE CELL

The Journal of Cell Biology ◽

10.1083/jcb.46.2.342 ◽

1970 ◽

Vol 46 (2) ◽

pp. 342-353 ◽

Cited By ~ 24

Author(s):

Samuel W. Cushman

Keyword(s):

Electron Microscopy ◽

Fatty Acids ◽

Colloidal Gold ◽

Intracellular Transport ◽

Nonesterified Fatty Acid ◽

Experimental Conditions ◽

Nonesterified Fatty Acids ◽

Adipose Cell ◽

Cell Functions ◽

The Relationship

Pinocytic activity in the adipose cell has been examined by measuring the uptake of colloidal gold. Pinocytic activity occurs in the isolated adipose cell under all experimental conditions; a portion of the vesicular elements of the cell can be identified by electron microscopy as pinocytic in origin. The isolated adipose cell appears to take up serum albumin by pinocytosis. Pinocytic activity in the isolated adipose cell is enhanced by epinephrine, but not by insulin. The relationship between pinocytosis and the metabolic activity of the adipose cell has been studied by measuring simultaneously the uptake of radioactive colloidal gold, the incorporation of 14C-counts from U-glucose-14C into CO2, total lipid, triglyceride glycerol and triglyceride fatty acids, and the release of nonesterified fatty acids in the absence of hormones and in the presence of insulin or epinephrine. Correlations between hormone-produced alterations in lipid metabolism and in pinocytic activity suggest that intracellular nonesterified fatty acid levels are a factor in the regulation of both the cell's pinocytic activity and its metabolism and that pinocytosis in the adipose cell functions in the extracellular-intracellular transport of nonesterified fatty acids.

Download Full-text