scholarly journals Effects of chromium picolinate on in vitro lipogenesis and lipolysis in adipose tissue and protein synthesis in liver tissue of pigs

1998 ◽  
Vol 11 (4) ◽  
pp. 428-433 ◽  
Author(s):  
Y. J. Choi ◽  
H. G. Kim ◽  
J. S. Cho ◽  
I. B. Chung ◽  
Y. H. Kim ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Adipose Tissue ◽  
Liver Tissue ◽  
Chromium Picolinate

scholarly journals PPARγ regulates adipose triglyceride lipase in adipocytes in vitro and in vivo

2007 ◽  
Vol 293 (6) ◽  
pp. E1736-E1745 ◽  
Author(s):  
Erin E. Kershaw ◽  
Michael Schupp ◽  
Hong-Ping Guan ◽  
Noah P. Gardner ◽  
Mitchell A. Lazar ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Adipose Tissue ◽  
Lipid Metabolism ◽  
Protein Synthesis Inhibitor ◽  
Adipose Triglyceride Lipase ◽  
Dependent Manner ◽  
Triglyceride Lipase ◽  
Brown Adipose

Peroxisome proliferator-activated receptor-γ (PPARγ) regulates adipocyte genes involved in adipogenesis and lipid metabolism and is the molecular target for thiazolidinedione (TZD) antidiabetic agents. Adipose triglyceride lipase (ATGL) is a recently described triglyceride-specific lipase that is induced during adipogenesis and remains highly expressed in mature adipocytes. This study evaluates the ability of PPARγ to directly regulate ATGL expression in adipocytes in vitro and in vivo. In fully differentiated 3T3-L1 adipocytes, ATGL mRNA and protein are increased by TZD and non-TZD PPARγ agonists in a dose- and time-dependent manner. Rosiglitazone-mediated induction of ATGL mRNA is rapid and is not inhibited by the protein synthesis inhibitor cycloheximide, indicating that intervening protein synthesis is not required for this effect. Rosiglitazone-mediated induction of ATGL mRNA and protein is inhibited by the PPARγ-specific antagonist GW-9662 and is also significantly reduced following siRNA-mediated knockdown of PPARγ, supporting the direct transcriptional regulation of ATGL by PPARγ. In vivo, ATGL mRNA and protein are increased by rosiglitazone treatment in white and brown adipose tissue of mice with and without obesity due to high-fat diet or leptin deficiency. Thus, PPARγ positively regulates ATGL mRNA and protein expression in mature adipocytes in vitro and in adipose tissue in vivo, suggesting a role for ATGL in mediating PPARγ's effects on lipid metabolism.

scholarly journals The effect of insulin and glucocorticoids on the synthesis and degradation of phosphoenolpyruvate carboxykinase (GTP) in rat adipose tissue cultured in vitro

1976 ◽  
Vol 158 (1) ◽  
pp. 9-16 ◽  
Author(s):  
O Meyuhas ◽  
L Reshef ◽  
F J Ballard ◽  
R W Hanson
Keyword(s):  
Protein Synthesis ◽  
Adipose Tissue ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Epididymal Adipose Tissue ◽  
Large Size ◽  
A Value ◽  
Rat Adipose Tissue ◽  
Synthesis And Degradation

1. Epididymal adipose tissue from the rat was maintained in culture for periods of up to 96h. 2. After an initial decrease in protein synthesis during the first 24h of culture, the adipose tissue recovered its capacity to synthesize and accumulate proteins of a relatively large size. 3. The activity of phosphoenolpyruvate carboxykinase decreased in a parallel manner, but increased again after 24h of incubation of the tissue in culture, to a value twice that noted in the tissue in vivo. This increase in enzyme activity was due to an increase in its rate of synthesis. 4. Both insulin and dexamethasone (9alpha-fluoro-16alpha-methyl-11beta,17,-21-trihydroxypregna-1,4-diene-3,20-dione) inhibited phosphoenolpyruvate carboxykinase synthesis, but dexamethasone also decreased total protein synthesis. 5. The half-life of phosphoenolpyruvate carboxykinase in adipose tissue cultured in vitro was 5-7h and was not altered by insulin or dexamethasone. 6. It is concluded that both insulin and glucocroticoids lower the activity of phosphoenolpyruvate carboxykinase in rat adipose tissue by decreasing its rate of synthesis.

Leucine is a direct-acting nutrient signal that regulates protein synthesis in adipose tissue

2002 ◽  
Vol 283 (3) ◽  
pp. E503-E513 ◽  
Author(s):  
Christopher J. Lynch ◽  
Brian J. Patson ◽  
Joshua Anthony ◽  
Alain Vaval ◽  
Leonard S. Jefferson ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Adipose Tissue ◽  
Plasma Insulin ◽  
Mammalian Target Of Rapamycin ◽  
Initiation Factor ◽  
Sprague Dawley ◽  
Initiation Phase ◽  
Treatment Conditions ◽  
Direct Acting

In freshly isolated rat adipocytes, leucine or its analog norleucine activates the mammalian target of rapamycin (mTOR)-signaling pathway. This results in phosphorylation of the ribosomal protein S6 kinase 1 (S6K1) and eukaryotic initiation factor 4E-binding protein-1 (4E-BP1), two proteins involved in the initiation phase of protein synthesis. The purpose of the studies reported herein was to address the question of whether or not these in vitro effects of leucine and norleucine on adipocytes could be extended to the intact animal and to other tissues. To accomplish this, food-deprived (18 h) male Sprague-Dawley rats were orally administered solutions (2.5 ml/100 g body wt) containing normal saline (0.9% NaCl), a carbohydrate mixture (26.2% d-glucose and 26.2% sucrose), leucine (5.4%), or norleucine (5.4%). The protein synthetic responses of adipose tissue were measured and compared with those of other tissues. In addition, S6K1 and 4E-BP1 phosphorylation was measured, as was the plasma concentration of insulin and tissue ATP concentrations. Leucine administration stimulated protein synthesis in adipose tissue, gastrocnemius, and kidney but not in liver and heart. Norleucine stimulated protein synthesis in all of the tissues tested but, in contrast to leucine, without affecting plasma insulin concentrations. The carbohydrate meal had no effect on protein synthesis in any tissue tested but elicited a robust increase in plasma insulin. These findings provide support for a role of leucine as a direct-acting nutrient signal for stimulation of protein synthesis in adipose tissue as well as other select tissues. In adipose tissue, the effects of the different treatment conditions on the acute regulation of protein synthesis closely correlated with changes in phosphorylation of S6K1 and 4E-BP1; however, this correlation did not exist in all tissues examined. This result implies that leucine or norleucine may acutely stimulate protein synthesis, at least in some tissues, by a mechanism that is independent of both S6K1 and 4E-BP1 phosphorylation.

Protein synthesis in vitro in cultures of the subepidermal adipose tissue and the ovary of the shrimp Penaeus semisulcatus

1989 ◽  
Vol 21 (6) ◽  
pp. 911-916 ◽  
Author(s):  
M. Fainzilber ◽  
C.L Browdy ◽  
M. Tom ◽  
E. Lubzens ◽  
S.W. Applebaum
Keyword(s):  
Protein Synthesis ◽  
Adipose Tissue ◽  
Penaeus Semisulcatus

THE IN VITRO UTILIZATION AND PRODUCTION OF NON-ESTERIFIED FATTY ACIDS BY ADRENALECTOMIZED RATS

1961 ◽  
Vol 39 (6) ◽  
pp. 1061-1065 ◽  
Author(s):  
W. F. Perry ◽  
Helen F. Bowen
Keyword(s):  
Carbon Dioxide ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Liver Tissue ◽  
In Vitro Production ◽  
Esterified Fatty Acids ◽  
Adrenalectomized Animal ◽  
Vitro Production ◽  
Adrenalectomized Rats

The in vitro utilization of non-esterified fatty acids by various tissues and the in vitro production of non-esterified fatty acids by adipose tissue have been compared in normal and adrenalectomized rats. It was found that the production of NEFA by adipose tissue was similar in both groups of animals but that the in vitro utilization of NEFA and production of carbon dioxide by heart, diaphragm, kidney, and liver tissue was greater in the adrenalectomized animal. These findings together with the depletion of fat content of the depots are interpreted as indicating that in the adrenalectomized state there is increased peripheral utilization of fatty acids.

scholarly journals In Vitro Evaluation of Cytotoxicity and Proliferative Effects of Lyophilized Porcine Liver Tissue on HepG2 Hepatoma Cells and Adipose-Tissue-Derived Mesenchymal Stromal Cells

2021 ◽  
Vol 11 (15) ◽  
pp. 6691
Author(s):  
Priscilla Berni ◽  
Virna Conti ◽  
Orlando Ferroni ◽  
Roberto Ramoni ◽  
Giuseppina Basini ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Cell Count ◽  
Mtt Assay ◽  
Stromal Cells ◽  
Liver Tissue ◽  
Cell Types ◽  
Porcine Liver ◽  
Direct Cell ◽  
Liver Powder

In recent years, nutritional supplements from different sources have been widely considered to support medical treatments in patients affected by chronic hepatopathies. Their potential therapeutic benefit has been recognized, but some evidence of safety issues has been reported. Recently it has been hypothesized that the liver could produce various of bioactive factors to maintain organ homeostasis and promote tissue healing. Thus, liver-specific preparations containing bioactive factors could provide a suitable substrate for in vitro study of liver tissue maintenance/healing, as a prospective regenerative medicine approach. Furthermore, they could represent a dietary supplement or nutraceutical for adjuvant therapies when correctly prepared and formulated. This work aims to provide data about the safety and biological activity of a freeze-dried porcine liver preparation. The lyophilized powder obtained from the whole organ has been tested in term of in vitro cell cytotoxicity (MTT assay) and proliferation assays (bromo-deoxyuridine incorporation and direct cell count) in two different cell types: human hepatoma HepG2 cell line and adipose-tissue-derived canine mesenchymal stromal cells (At-MSCs). At concentration levels between 100 to 500 µg/mL, the lyophilized liver powder stimulated mitochondrial metabolism as assessed by MTT assay (p ≤ 0.001 for HepG2 and for At-MSCs) and induced an increase in bromo-deoxyuridine incorporation in both cell types (p ≤ 0.01 for HepG2 and p < 0.001 for At-MSCs). In addition, direct cell count demonstrated a higher proliferative activity in treated At-MSCs (p < 0.001). Although preliminary, these data suggest that the whole-liver powder is noncytotoxic in vitro and may represent a stimulus to cell metabolism and proliferation. Further studies are needed to detect the bioactive components of the supplement and characterize in deeper detail the cellular pathways that they can modulate.

ACETATE UTILIZATION BY LIVER AND ADIPOSE TISSUE OF RATS FASTED IN THE COLD

1958 ◽  
Vol 36 (1) ◽  
pp. 237-241
Author(s):  
William F. Perry
Keyword(s):  
Carbon Dioxide ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Liver Tissue ◽  
Carbon Dioxide Production ◽  
Acetate Incorporation ◽  
Fasted Rats ◽  
Glucose Supplementation

The in vitro incorporation of 1-C14 and 2-C14 acetate into fatty acids and carbon dioxide by liver and adipose tissue was studied in rats fasted at 5 °C. for 24 hours. Compared with fed rats at room temperature, there was a marked decrease in the incorporation of the acetate carbons into fatty acids and carbon dioxide by liver tissue. A pronounced decrease in acetate incorporation into fatty acid was also noted with adipose tissue from these same animals, but only a slight decrease in incorporation into carbon dioxide. Addition of glucose to the incubation medium caused increases in fatty acid formation by liver and adipose tissue from both normal and fasted animals, but glucose supplementation, while increasing the incorporation of acetate into carbon dioxide by liver tissue from cold fasted rats, did not affect carbon dioxide production by liver tissue from normal animals. Incorporation of acetate into carbon dioxide by adipose tissue was unaffected by glucose supplementation with tissue from both normal and cold fasted rats.

Specificity of insulin or oxytocin stimulation of protein synthesis in adipose tissue

1964 ◽  
Vol 207 (5) ◽  
pp. 1169-1172 ◽  
Author(s):  
M. E. Krahl
Keyword(s):  
Protein Synthesis ◽  
Adipose Tissue ◽  
Glucose Uptake ◽  
Lipid Synthesis ◽  
Specific Effect ◽  
Acetate Incorporation ◽  
Enhance Protein Synthesis ◽  
Rat Adipose Tissue ◽  
Synthetic Oxytocin

Insulin stimulates glucose uptake, fat synthesis, and incorporation of amino acids into protein of rat adipose tissue. Other agents having insulinlike effects on glucose metabolism have now been tested for their ability to promote protein synthesis in this in vitro system. Rat epididymal fat pads were incubated in Krebs bicarbonate medium containing glucose or pyruvate, acetate-1-C14 as precursor for lipids, or (in separate experiments) histidine-2(ring)-C14 as precursor for protein. Glucose uptake was measured by the glucose oxidase method, and radioactivity of lipid and protein fractions was estimated. Synthetic oxytocin (Sandoz), 0.1–10 U/ml, stimulated glucose uptake, acetate incorporation into lipid, and histidine-C14 incorporation into protein when glucose was present; unlike insulin, oxytocin did not enhance protein synthesis when pyruvate replaced glucose in the medium. RNA (1 mg/ml), nicotinic acid (0.001 m), and protamine sulfate (1 mg/ml) each stimulated glucose uptake and acetate incorporation into lipid, but did not enhance histidine-C14 incorporation into protein. It is concluded that in adipose tissue insulin has a specific effect on protein synthesis which cannot be mimicked by other agents which stimulate glucose uptake or lipid synthesis.

ACETATE UTILIZATION BY LIVER AND ADIPOSE TISSUE OF RATS FASTED IN THE COLD

1958 ◽  
Vol 36 (2) ◽  
pp. 237-241 ◽  
Author(s):  
William F. Perry
Keyword(s):  
Carbon Dioxide ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Liver Tissue ◽  
Carbon Dioxide Production ◽  
Acetate Incorporation ◽  
Fasted Rats ◽  
Glucose Supplementation

The in vitro incorporation of 1-C14 and 2-C14 acetate into fatty acids and carbon dioxide by liver and adipose tissue was studied in rats fasted at 5 °C. for 24 hours. Compared with fed rats at room temperature, there was a marked decrease in the incorporation of the acetate carbons into fatty acids and carbon dioxide by liver tissue. A pronounced decrease in acetate incorporation into fatty acid was also noted with adipose tissue from these same animals, but only a slight decrease in incorporation into carbon dioxide. Addition of glucose to the incubation medium caused increases in fatty acid formation by liver and adipose tissue from both normal and fasted animals, but glucose supplementation, while increasing the incorporation of acetate into carbon dioxide by liver tissue from cold fasted rats, did not affect carbon dioxide production by liver tissue from normal animals. Incorporation of acetate into carbon dioxide by adipose tissue was unaffected by glucose supplementation with tissue from both normal and cold fasted rats.

scholarly journals Effects of insulin, glucocorticoids and adrenaline on the activity of rat adipose-tissue lipoprotein lipase

1980 ◽  
Vol 188 (1) ◽  
pp. 185-192 ◽  
Author(s):  
P Ashby ◽  
D S Robinson
Keyword(s):  
Protein Synthesis ◽  
Adipose Tissue ◽  
Lipoprotein Lipase ◽  
Lipase Activity ◽  
Lipoprotein Lipase Activity ◽  
Fat Bodies ◽  
Rat Adipose Tissue ◽  
Adipose Tissue Lipoprotein Lipase

The lipoprotein lipase activity of epididymal fat-bodies from starved rats was measured during incubations at 37 degrees C in vitro. Protein synthesis independent activation of the enzyme, previously observed during incubations at 25 decrease C, also occurs at 37 degrees C. Protein-synthesis-dependent increases in the activity of the enzyme occur in the presence of insulin and are markedly potentiated by glucocorticoids. The effects on the activity of the enzyme of insulin alone, or in the presence of glucocorticoids, are correlated with its effects on total protein synthesis in the tissue. Adrenaline antagonizes the increase in activity of the enzyme brought about by insulin and abolishes the potentiation of insulin action by glucocorticoids. These changes may be due, at least in part, to its stimulation of inactivation of the enzyme in the tissue. It is suggested that changes in adipose-tissue lipoprotein lipase activity that occur with changes in nutritional status in vivo result from the combined effects of changes in plasma insulin and glucocorticoid concentrations.

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