Adaptations for hibernation in the depot fats of a ground squirrel (Spermophilus beldingi)

1991 ◽  
Vol 69 (11) ◽  
pp. 2707-2711 ◽  
Author(s):  
Craig L. Frank
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Melting Point ◽  
Ground Squirrel ◽  
Unsaturated Fatty Acids ◽  
Ground Squirrels ◽  
Body Temperatures ◽  
Melting Points ◽  
Spermophilus Beldingi ◽  
Free Ranging

Ground squirrels are small herbivores that hibernate during winter. The ecological–nutritional limitations on hibernation are virtually unknown, but one constraint may be the melting point of stored fat. Lipids must be fluid to be metabolizable, and body temperatures maintained during hibernation are usually 30 °C below the melting point of typical mammalian fats. Fats containing greater amounts of unsaturated fatty acids, however, have correspondingly lower melting points. White adipose tissue was sampled from free-ranging Belding's ground squirrels, Spermophilus beldingi, during both the summer and fall. The lipids were twice as unsaturated as those of other rodent species, most of the increased unsaturation being due to the accumulation of plant-produced polyunsaturated fatty acids derived from the animals' diet. The melting points of S. beldingi fats were consequently 25 °C lower than those of other mammals. These results suggest that ground squirrels may depend upon their plant diet for the polyunsaturates necessary to produce the lipids with low melting points that are needed for hibernation.

Ketone body metabolism in a ground squirrel during hibernation and fasting

1985 ◽  
Vol 249 (4) ◽  
pp. R462-R470 ◽  
Author(s):  
B. L. Krilowicz
Keyword(s):  
Energy Source ◽  
Glucose Uptake ◽  
Ground Squirrel ◽  
Ketone Body ◽  
Glucose Utilization ◽  
Ground Squirrels ◽  
Body Protein ◽  
Muscle Tissues ◽  
Spermophilus Beldingi

Hibernating Belding's ground squirrels (Spermophilus beldingi) are ketotic relative to fed nonhibernators. Muscles from torpid individuals, when incubated in media containing physiological concentrations of glucose and ketone, show reduced uptake of glucose in the presence of ketone. The magnitude of the reduction is dependent on ketone concentration and reaches 60% in heart and 100% in pectoralis at 1.4 mM ketone. Fasted squirrels are also ketotic. However, ketone does not reduce glucose uptake in muscles from fed or fasted animals. Glucose utilization by muscles decreases during a long-term fast, but the reduction is independent of ketone. Thus both a long-term fast and hibernation lead to changes in muscle tissues that decrease their reliance on glucose as an energy source. Ketosis leads to glucose sparing during hibernation, whereas muscle glucose utilization is decreased independently of ketone during a fast. The glucose sparing achieved in both hibernation and fasting leads to conservation of body protein, the major source of gluconeogenic precursors in fasting mammals.

A note on the melting-point of paraffins and fatty acids

1938 ◽  
Vol 34 (3) ◽  
pp. 459-464 ◽  
Author(s):  
E. B. Moullin
Keyword(s):  
Fatty Acids ◽  
Melting Point ◽  
Melting Temperature ◽  
Smooth Curve ◽  
Melting Points ◽  
Normal Paraffin ◽  
Simple Interpretation

The purpose of this note is to draw attention to a certain correspondence between the melting-points of normal paraffins and of fatty acids and to indicate a simple interpretation of this phenomenon. If the number of carbon atoms in a normal paraffin is plotted against the corresponding melting temperature, all the points in the diagram lie very close to a smooth curve drawn among them. If a similar diagram is made for the fatty acids, the points corresponding to an even number of carbon atoms lie on a curve of the same character as that found for paraffins. The points for an odd number of carbon atoms lie on a separate but similar curve, exemplifying the well-known alternation property.

Results of the study on principles of brown adipose tissue deposits and characteristics of its fatty acids in pasture sheep lambs

2015 ◽  
Vol 15 (2) ◽  
pp. 38-42
Author(s):  
Ch Khorolmaa ◽  
Sh Demberel ◽  
B Battsetseg ◽  
G Gereltsetseg ◽  
S Andrei
Keyword(s):  
Fatty Acids ◽  
Body Weight ◽  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
White Adipose Tissue ◽  
Unsaturated Fatty Acids ◽  
Total Body Weight ◽  
Fatty Acids Composition ◽  
Brown Adipose ◽  
Total Body

Brown adipose tissue in newborn lambs accounts for 4.52% of total body weight, then during postpartum period it intensively decreases, reaching 1.5% after a week, and finally it is gradually adsorbed or replaced with white adipose tissue. Fatty acids composition of lamb brown adipose tissue includes 17 unsaturated fatty acids (53.23%) and 11 saturated ones (46.95%).Mongolian Journal of Agricultural Sciences Vol.15(2) 2015; 38-42

Altered adipose tissue metabolism in offspring of dietary obese rat dams

2011 ◽  
Vol 121 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Nassira Batoul Benkalfat ◽  
Hafida Merzouk ◽  
Samira Bouanane ◽  
Sid-Ahmed Merzouk ◽  
Jérôme Bellenger ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Unsaturated Fatty Acids ◽  
Cafeteria Diet ◽  
High Fat ◽  
Adipose Tissue Metabolism ◽  
Tissue Metabolism ◽  
Obese Rats ◽  
Maternal Overnutrition ◽  
The Impact

To investigate further the mechanisms of developmental programming, we analysed the effects of maternal overnutrition and of postnatal high-fat feeding on adipose tissue metabolism in the offspring. Postnatal changes in serum adiponectin, leptin and TAG [triacylglycerol (triglyceride)] levels, adipose tissue TAGs, fatty acids and enzyme activities were determined in offspring of cafeteria-diet-fed dams during gestation and lactation, weaned on to standard chow or on to cafeteria diet. Obese rats showed higher adiposity (+35% to 85%) as well as a significant increase in serum glucose, insulin, leptin, adiponectin and TAG levels (P<0.01) and adipose tissue LPL (lipoprotein lipase) and GPDH (glycerol-3-phosphate dehydrogenase) activities (P<0.01), compared with control pups at weaning (day 21) and at adulthood (day 90). Adipose HSL (hormone-sensitive lipase) activity was increased only at day 90 (P<0.05), and FAS (fatty acid synthase) activity remained unchanged. The proportions of SFAs (saturated fatty acids) and MUFAs (mono-unsaturated fatty acids) and the Δ9-desaturation index were significantly increased (P<0.05), whereas PUFAs (polyunsaturated fatty acids) were decreased (P<0.01) in serum and adipose TAGs of obese pups compared with controls. The cafeteria diet at weaning induced more severe abnormalities in obese rats. In conclusion, maternal overnutrition induced permanent changes in adipose tissue metabolism of the offspring. These pre-existing alterations in offspring were worsened under a high-fat diet from weaning to adulthood. Consequently, adipose adipokines and enzymes could provide a potential therapeutic target, and new investigations in this field could constitute strategies to improve the impact of early-life overnutrition.

scholarly journals Effect of diethylstilboestrol on adipose-tissue lipids

1965 ◽  
Vol 97 (2) ◽  
pp. 371-374 ◽  
Author(s):  
JD Sink ◽  
CK Huston ◽  
JW Shigley
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid Composition ◽  
Oleic Acid ◽  
Stearic Acid ◽  
Palmitoleic Acid ◽  
Unsaturated Fatty Acids ◽  
Bos Taurus ◽  
Saturated Fatty Acids ◽  
Tissue Lipids

1. The effect of diethylstilboestrol on the fatty acid composition of adipose-tissue lipids of the ox (Bos taurus) was studied. 2. The capsula adiposa (perirenal) was shown to contain more total saturated fatty acids, whereas more total unsaturated fatty acids were found in the panniculus adiposus (subcutaneous). 3. Significantly more stearic acid and linolenic acid were obtained from the capsula adiposa, whereas the panniculus adiposus contained more myristoleic acid, palmitoleic acid and oleic acid. 4. Implanting diethylstilboestrol significantly increased the deposition of the saturated fatty acids, particularly stearic acid. 5. A decrease in the deposition of total unsaturated fatty acids, myristoleic acid, palmitoleic acid and linoleic acid can also be attributed to the diethylstilboestrol treatment.

scholarly journals Assessment of individual fatty acid intake

2000 ◽  
Vol 59 (2) ◽  
pp. 187-191 ◽  
Author(s):  
Marie M. Cantwell
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Dietary Assessment ◽  
Individual Fatty Acid ◽  
Fatty Acid Intake ◽  
Tissue Concentrations ◽  
Acid Intake ◽  
Habitual Intake

Dietary assessment of individual fatty acid intake is difficult due to a number of limitations. Information regarding the type, quantity and brand-name of fat used in cooking and at the table is required. In addition, margarine manufacturers may change the component oils used for reasons of cost, which changes the fatty acid composition of their products from season-to-season. Independent markers of fatty acid intake are required, therefore, to compensate for these limitations. Adipose tissue concentrations have been used as a measure of habitual intake of fatty acid groups and individual fatty acids in numerous studies. Saturated (SFA) and monounsaturated fatty acids (MUFA) are generally poorly correlated with adipose tissue concentrations, which can be explained partly by endogenous synthesis. In general, adipose tissue concentrations of exogenously-produced fatty acids (n-3 and n-6 polyunsaturated fatty acids (PUFA)) are well correlated with estimates of habitual intake. Correlations between dietary trans unsaturated fatty acids (TUFA) and adipose tissue concentrations vary between countries, which may be due to differences in dietary sources. Correlations may be affected by differences in bioavailability or selective retention of fatty acids in certain tissue lipids.

scholarly journals Unsaturated Fatty Acids in Fish Oil Play a Role in Adequate Fat Distribution to Plasma, Liver and White Adipose Tissue

2011 ◽  
Vol 57 (4) ◽  
pp. 341-349 ◽  
Author(s):  
Sachiko Shiba ◽  
Nobuyo Tsunoda ◽  
Kanako Ito ◽  
Masaki Wakutsu ◽  
Etsuko Muraki ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fish Oil ◽  
White Adipose Tissue ◽  
Unsaturated Fatty Acids ◽  
Fat Distribution

Adipose tissue stearoyl-CoA desaturase mRNA is increased by obesity and decreased by polyunsaturated fatty acids

1996 ◽  
Vol 271 (1) ◽  
pp. E44-E49 ◽  
Author(s):  
B. H. Jones ◽  
M. A. Maher ◽  
W. J. Banz ◽  
M. B. Zemel ◽  
J. Whelan ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Polyunsaturated Fatty Acids ◽  
Unsaturated Fatty Acids ◽  
Corn Oil ◽  
Zucker Rats ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Obese Zucker Rats ◽  
Stearoyl Coa Desaturase

Stearoyl-CoA desaturase (SCD) is a key regulatory enzyme in the synthesis of unsaturated fatty acids. Although regulation of hepatic SCD by obesity and polyunsaturated fatty acids (PUFA) has been well investigated, no studies have addressed whether similar regulation occurs in adipose tissue. We addressed these questions by feeding control (12% corn oil) and high-PUFA (48% corn oil) diets to lean and obese Zucker rats and analyzing SCD mRNA levels in adipose tissue and liver. We report that SCD mRNA content was dramatically elevated in adipose tissue of obese vs. lean rats on both diets and was significantly decreased by PUFA in both genotypes. Interestingly, we demonstrate that SCD expression was directly downregulated in a dose dependent manner by PUFA in 3T3-L1 adipocytes. We conclude that 1) obese Zucker rats overexpress the SCD gene in both liver and adipose tissue and 2) PUFA directly suppress SCD expression in adipocytes. Further studies will elucidate the mechanisms responsible for obesity- and PUFA-mediated regulation of SCD in adipose cells.

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