Nutritional Regulation of the Activities of Lipogenic Enzymes of Rat Liver and Brown Adipose Tissue

Abstract Nutrition-induced effects on the activity of enzymes of lipogenesis, fatty acid synthase (FAS; EC 2.3.1.85). ATP citrate lyase (ACL; EC 4.1.3.8), malic enzyme (ME; EC 1.1.1.40), glucose-6-phosphate dehydrogenase (G6PDH; EC 1.1.1.49) and 6-phosphogluconate dehy drogenase (PGDH; EC 1.1.1.44) were investigated in liver and interscapular brown adipose tissue (BAT) of rats. The lipogenic enzymes could be grouped into two categories according to their response to dietary manipulations; FAS and ACL. both key enzymes of lipogenesis, responded fast and strongly to dietary manipulations. ME, G6PDH and PDGH, enzymes which also contribute to metabolic pathways other than lipogenesis, responded in a more sustained and less pronounced fashion. Feed deprivation caused the specific activities of lipogenic enzymes to decline several-fold. Refeeding of previously fasted (up to 3 days) animals increased the activities dramatically (10-to 25-fold) to far above pre-fasting levels (“overshoot”). Repetition of the fasting/refeeding regimen increasingly impaired the ability of both tissues to synthesize overshooting enzyme activities in the subsequent refeeding period. The fasting-induced decline of the activities was prevented when sugars were provided to the animals via drinking water. The sugars displayed different effectivities; sucrose= glucose> fructose> maltose » lactose. Sugars as the sole nutrient after fasting were also able to induce overshooting enzyme activities. Again, activities of FAS and ACL responded in a more pronounced fashion than the other three enzymes. Transition from feeding one diet to feeding a new diet of different composition led to adaptation of the lipogenic enzyme activities to levels characteristic for the new diet. Replacing a low-carbohydrate with a high-carbohydrate diet proceeded with major alterations of enzyme activities. This process of attaining a new level took up to 20 days and involved pronounced oscillations of the specific activities. In contrast, when a high-carbohydrate diet was replaced with another diet, particular one high in fat, transition to new enzyme activities was completed within 2 -3 days and proceeded without oscillations. All dietary manipulations caused more pronounced responses in young (35d-old) than in adult (180d-old) animals.

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Low-protein, high-carbohydrate diet increases glucose uptake and fatty acid synthesis in brown adipose tissue of rats

Nutrition ◽

10.1016/j.nut.2013.10.004 ◽

2014 ◽

Vol 30 (4) ◽

pp. 473-480 ◽

Cited By ~ 10

Author(s):

Suélem Aparecida de França ◽

Maísa Pavani dos Santos ◽

Roger Vinícius Nunes Queiroz da Costa ◽

Mendalli Froelich ◽

Samyra Lopes Buzelle ◽

...

Keyword(s):

Adipose Tissue ◽

Fatty Acid ◽

Brown Adipose Tissue ◽

Fatty Acid Synthesis ◽

Acid Synthesis ◽

High Carbohydrate Diet ◽

Carbohydrate Diet ◽

High Carbohydrate ◽

Low Protein ◽

Brown Adipose

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A Low-Protein, High-Carbohydrate Diet Stimulates Thermogenesis in the Brown Adipose Tissue of Rats via ATF-2

Lipids ◽

10.1007/s11745-016-4119-z ◽

2016 ◽

Vol 51 (3) ◽

pp. 303-310 ◽

Cited By ~ 11

Author(s):

Suélem A. de França ◽

Maísa P. dos Santos ◽

Franciele Przygodda ◽

Maria Antonieta R. Garófalo ◽

Isis C. Kettelhut ◽

...

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

High Carbohydrate Diet ◽

Carbohydrate Diet ◽

High Carbohydrate ◽

Low Protein ◽

Brown Adipose

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Effects of high-carbohydrate diets on lipogenesis in rat interscapular brown adipose tissue

Biochemical Journal ◽

10.1042/bj2060667 ◽

1982 ◽

Vol 206 (3) ◽

pp. 667-669 ◽

Cited By ~ 2

Author(s):

P. John Weaire ◽

Tazeen F. Kanagasabai

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

White Adipose Tissue ◽

White Bread ◽

Lipogenic Enzymes ◽

Adipose Tissues ◽

Interscapular Brown Adipose Tissue ◽

High Carbohydrate ◽

Brown Adipose

Cycloplasmic preparations from brown and white adipose tissues were assayed for three lipogenic enzymes throughout a programme of starvation followed by refeeding on either a normal or a white-bread diet. In the brown adipose tissue of rats fed on a white-bread diet the three enzymes were elevated to levels significantly higher than those in white adipose tissue.

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Developmental changes in fatty acid synthesis in interscapular brown adipose tissue of lean and genetically obese (ob/ob) mice

Biochemical Journal ◽

10.1042/bj2120393 ◽

1983 ◽

Vol 212 (2) ◽

pp. 393-398 ◽

Cited By ~ 33

Author(s):

S W Mercer ◽

P Trayhurn

Keyword(s):

Adipose Tissue ◽

Fatty Acid ◽

Brown Adipose Tissue ◽

Fatty Acid Synthesis ◽

Acid Synthesis ◽

Obese Mice ◽

Carbohydrate Diet ◽

Interscapular Brown Adipose Tissue ◽

Brown Adipose

Fatty acid synthesis was measured in vivo with 3H2O in interscapular brown adipose tissue of lean and genetically obese (ob/ob) mice. At 26 days of age, before the development of hyperphagia, synthesis in brown adipose tissue was higher in the obese than in the lean mice; synthesis was also elevated in the liver, white adipose tissue and carcass of the obese mice. At 8 weeks of age, when hyperphagia was well established, synthesis remained elevated in all tissues of the obese mice, with the exception of brown adipose tissue. Elevated synthesis rates were not apparent in brown adipose tissue of the obese mice at 14 days of age, nor at 35 days of age. These results demonstrate that brown adipose tissue in ob/ob mice has a transitory hyperlipogenesis at, and just after, weaning on to a low-fat/high-carbohydrate diet. Once hyperphagia has developed, by week 5 of life, brown adipose tissue is the only major lipogenic tissue in the obese mice not to exhibit elevated rates of fatty acid synthesis; this suggests that insulin resistance develops much more rapidly in brown adipose tissue than in other lipogenic tissues of the ob/ob mouse.

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Effect of thyroxine on glutathione-dependent antioxidant enzyme activities and glutathione content in the interscapular brown adipose tissue of different maturated rats

Jugoslovenska medicinska biohemija ◽

10.2298/jmh0404367s ◽

2004 ◽

Vol 23 (4) ◽

pp. 367-373 ◽

Cited By ~ 1

Author(s):

Zorica Saicic ◽

Dejan Mijalkovic ◽

Aleksandra Nikolic ◽

Dusko Blagojevic ◽

Mihajlo Spasic ◽

...

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Antioxidant Enzyme ◽

Enzyme Activities ◽

Antioxidant Enzyme Activities ◽

Developmental Phase ◽

Interscapular Brown Adipose Tissue ◽

Brown Adipose ◽

Old Rats ◽

Different Response

Effect of thyroxine on glutathione-dependent antioxidant enzyme activities and glutathione (GSH) content in the interscapular brown adipose tissue (IBAT) of different aged rats were studied. Male Mill Hill hybrid hooded rats aged 15, 45 and 75 days were treated with L-thyroxine, T4 (40 mg/100 g body mass), s.c., one dose per day, 14 days (finally aged 30, 60 and 90 days, respectively). Effect of T4 on GSH-dependent antioxidant enzyme activities in the IBAT differs with respect to age. T4 treatment gradually decrease activities of all GSH-dependent antioxidant enzymes in 60 and 90 days old rats in comparison to young ones. GSH content in animals of 30 and 60 days old rats are lower in comparison with 90 days old rats, but the effects are oppposite. L-thyroxine treatment significantly increase GSH content in 30 days old rats (p<0.001) in respect with coresponding controls, while decrease in 60 and 90 days old animals were detected (p<0.01). Different response of non-mature rats to thyroxine comparing to older rats could be attributed to the difference in thyroxine metabolism and developmental phase of regulatory physiological systems maturation including antioxidative.

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Glucose transporter expression and glucose utilization in skeletal muscle and brown adipose tissue during starvation and re-feeding

Biochemical Journal ◽

10.1042/bj2820231 ◽

1992 ◽

Vol 282 (1) ◽

pp. 231-235 ◽

Cited By ~ 11

Author(s):

D M Smith ◽

S R Bloom ◽

M C Sugden ◽

M J Holness

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Tibialis Anterior ◽

Glucose Transporter ◽

Glucose Utilization ◽

Interscapular Brown Adipose Tissue ◽

Glut 4 ◽

Mrna Concentration ◽

Brown Adipose ◽

Transporter Expression

Starvation (48 h) decreased the concentration of mRNA of the insulin-responsive glucose transporter isoform (GLUT 4) in interscapular brown adipose tissue (IBAT) (56%) and tibialis anterior (10%). Despite dramatic [7-fold (tibialis anterior) and 40-fold (IBAT)] increases in glucose utilization after 2 and 4 h of chow re-feeding, no significant changes in GLUT 4 mRNA concentration were observed in these tissues over this re-feeding period. The results exclude changes in GLUT 4 mRNA concentration in mediating the responses of glucose transport in these tissues to acute re-feeding after prolonged starvation.

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Changes in β1- and β2-adrenergic receptor mRNA levels in brown adipose tissue and heart of hypothyroid rats

Biochemical Journal ◽

10.1042/bj2770625 ◽

1991 ◽

Vol 277 (3) ◽

pp. 625-629 ◽

Cited By ~ 30

Author(s):

J P Revelli ◽

R Pescini ◽

P Muzzin ◽

J Seydoux ◽

M G Fitzgerald ◽

...

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Adrenergic Receptor ◽

State Level ◽

Total Density ◽

Mrna Levels ◽

Interscapular Brown Adipose Tissue ◽

Brown Adipose ◽

Displacement Experiments ◽

Beta 2

The aim of the present work was to study the effect of hypothyroidism on the expression of the beta-adrenergic receptor (beta-AR) in interscapular brown adipose tissue and heart. The total density of plasma membrane beta-AR per tissue is decreased by 44% in hypothyroid rat interscapular brown adipose tissue and by 55% in hypothyroid rat heart compared with euthyroid controls. The effects of hypothyroidism on the density of both beta 1- and beta 2-AR subtypes were also determined in competition displacement experiments. The densities of beta 1- and beta 2-AR per tissue are decreased by 50% and 48% respectively in interscapular brown adipose tissue and by 52% and 54% in the heart. Northern blot analysis of poly(A)+ RNA from hypothyroid rat interscapular brown adipose tissue demonstrated that the levels of beta 1- and beta 2-AR mRNA per tissue are decreased by 73% and 58% respectively, whereas in hypothyroid heart, only the beta 1-AR mRNA is decreased, by 43%. The effect of hypothyroidism on the beta 1-AR mRNA is significantly more marked in the interscapular brown adipose tissue than in the heart. These results indicate that beta-AR mRNA levels are differentially regulated in rat interscapular brown adipose tissue and heart, and suggest that the decrease in beta-AR number in interscapular brown adipose tissue and heart of hypothyroid animals may in part be explained by a decreased steady-state level of beta-AR mRNA.

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Noxious and innocuous mechanical cutaneous stimulation increase the sympathetic efferent nerve activity innervating the interscapular brown adipose tissue in anesthetized rats

Journal of the Autonomic Nervous System ◽

10.1016/0165-1838(91)90234-t ◽

1991 ◽

Vol 32 (1) ◽

pp. 47-52 ◽

Cited By ~ 2

Author(s):

Mieko Kurosawa ◽

Akira Niijima

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Nerve Activity ◽

Efferent Nerve ◽

Interscapular Brown Adipose Tissue ◽

Cutaneous Stimulation ◽

Anesthetized Rats ◽

Brown Adipose

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Stimulatory, but not anxiogenic, doses of caffeine act centrally to activate interscapular brown adipose tissue thermogenesis in anesthetized male rats

Scientific Reports ◽

10.1038/s41598-020-80505-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

L. Van Schaik ◽

C. Kettle ◽

R. Green ◽

W. Sievers ◽

M. W. Hale ◽

...

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Basolateral Amygdala ◽

Free Breathing ◽

Male Rats ◽

Central Administration ◽

Hypothalamic Area ◽

Interscapular Brown Adipose Tissue ◽

Brown Adipose ◽

Brown Adipose Tissue Thermogenesis

AbstractThe role of central orexin in the sympathetic control of interscapular brown adipose tissue (iBAT) thermogenesis has been established in rodents. Stimulatory doses of caffeine activate orexin positive neurons in the lateral hypothalamus, a region of the brain implicated in stimulating BAT thermogenesis. This study tests the hypothesis that central administration of caffeine is sufficient to activate BAT. Low doses of caffeine administered either systemically (intravenous [IV]; 10 mg/kg) and centrally (intracerebroventricular [ICV]; 5–10 μg) increases BAT thermogenesis, in anaesthetised (1.5 g/kg urethane, IV) free breathing male rats. Cardiovascular function was monitored via an indwelling intra-arterial cannula and exhibited no response to the caffeine. Core temperature did not significantly differ after administration of caffeine via either route of administration. Caffeine administered both IV and ICV increased neuronal activity, as measured by c-Fos-immunoreactivity within subregions of the hypothalamic area, previously implicated in regulating BAT thermogenesis. Significantly, there appears to be no neural anxiety response to the low dose of caffeine as indicated by no change in activity in the basolateral amygdala. Having measured the physiological correlate of thermogenesis (heat production) we have not measured indirect molecular correlates of BAT activation. Nevertheless, our results demonstrate that caffeine, at stimulatory doses, acting via the central nervous system can increase thermogenesis, without adverse cardio-dynamic impact.

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