Lipogenesis in liver, lung and adipose tissue of rats fed with oleoylanilide

Oleoylanilide was administered orally to groups of rats according to different patterns. Subcellular fractionation of liver, lung and adipose tissue was then carried out in order to study the main enzyme activities involved in the lipogenesis. The observed findings indicate that adipose tissue and lung are the main target organs for the anilide, adipose tissue being involved in a general decrease of the enzyme activities, whereas transacylation reaction exhibits the most marked depletion of all the enzyme activities in the lung. The enzyme activities in liver were not markedly affected by this oral administration, although some data support the existence of a latent liver toxicity. These data suggest that oleoylanilide has the capacity to alter lipid metabolism of lung and adipose tissue to a considerable extent, whereas no major effect was produced in the liver. This different organ response could be related to the lymphatic gland via absorption of the substance.

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Amorphous silica nanoparticles induced spleen and liver toxicity after acute intravenous exposure in male and female rats

Toxicology and Industrial Health ◽

10.1177/07482337211010579 ◽

2021 ◽

pp. 074823372110105

Author(s):

Roberta Tassinari ◽

Andrea Martinelli ◽

Mauro Valeri ◽

Francesca Maranghi

Keyword(s):

Amorphous Silica ◽

Liver Toxicity ◽

Female Rats ◽

Histopathological Analysis ◽

Short Term ◽

Short Term Treatment ◽

Male And Female ◽

Male And Female Rats ◽

Target Organs ◽

Short Term Exposure

Synthetic amorphous silica (SAS) nanomaterial – consisting of aggregates and agglomerates of primary silicon dioxide (SiO2) particles in the nanorange (<100 nm) – is commonly used as excipient in pharmaceuticals, in cosmetics and as food additive (E551). The available data suggest that SAS nanoparticles (NP) after intravenous (IV) exposure persist in liver and spleen; however, insufficient data exist to verify whether SAS may also induce adverse effects. The aim of the present study was to verify the potential long-term effects of SAS NP (NM-203) on spleen and liver as target organs following short-term exposure. Adult male and female Sprague-Dawley rats were treated by IV injection in the tail vein with a single (1-day) dose (SD) and repeated (5-day) doses (RD) of 20 mg/kg bw per day of SAS dispersed in sterile saline solution as vehicle. Histopathological examinations of target organs were performed after 90 days. Tissue biodistribution and full characterization of NM-203, primary particle size 13–45 nm, was performed within the framework of the Nanogenotox project. No mortality or general toxicity occurred; histopathological analysis showed splenomegaly in the RD group accompanied by inflammatory granulomas in both sexes. Granulomas were also present in liver parenchyma in the RD (both sexes) and SD groups (male only). The histopathological results indicated that SAS NP have the potential to persist and induce sex-specific chronic inflammatory lesions in spleen and liver upon short-term treatment. Overall, the data showed that the widespread use of silica in drugs might elicit chronic reactions in spleen and liver prompting to the need of further investigations on the safety of SAS NP.

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Dihydroquercetin as potential immunonutrient in treatment of COVID-19

Medical alphabet ◽

10.33667/2078-5631-2021-21-28-32 ◽

2021 ◽

pp. 28-32

Author(s):

V. V. Tatarinov ◽

S. V. Orlova ◽

E. A. Nikitina ◽

E. V. Prokopenko ◽

A. N. Vodolazkaya ◽

...

Keyword(s):

Biological Activity ◽

Recovery Period ◽

Enzymatic Reactions ◽

Target Organs ◽

Wide Range ◽

Complex Therapy ◽

Main Target ◽

Low Toxicity ◽

Anti Inflammatory

The main aspects of the antiviral, anti-inflammatory, antioxidant and hepatoprotective properties of dihydroquercetin (DHQ), which may affect the course of COVID-19, are considered. Given the low toxicity and a wide range of biological activity, aimed not only at suppressing enzymatic reactions with the participation of coronavirus, but also at eliminating the lesions caused by it in all the main target organs, dihydroquercetin can be recommended for inclusion in the complex therapy of the disease and during the recovery period of COVID-19.

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Adipose-tissue lipoprotein lipase activity and cellularity in the genetically obese Zucker rat (fa/fa) (Short Communication)

Biochemical Journal ◽

10.1042/bj1320633 ◽

1973 ◽

Vol 132 (3) ◽

pp. 633-635 ◽

Cited By ~ 16

Author(s):

P. de Gasquet ◽

E. Péquignot ◽

D. Lemonnier ◽

A. Alexiu

Keyword(s):

Adipose Tissue ◽

Surface Area ◽

Lipoprotein Lipase ◽

Lipase Activity ◽

Enzyme Activities ◽

Short Communication ◽

Zucker Rat ◽

Lipoprotein Lipase Activity ◽

Obese Zucker Rat ◽

Adipose Tissue Lipoprotein Lipase

The lipoprotein lipase activity per adipocyte was increased in the genetically obese rat (fa/fa). However, there was no difference between obese and lean animals when the enzyme activities were related to adipocyte surface area. The possible implications of the findings are discussed.

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Cellularity and Lipogenic Enzyme Activities of Porcine Intramuscular Adipose Tissue

Journal of Animal Science ◽

10.2527/jas1974.383538x ◽

1974 ◽

Vol 38 (3) ◽

pp. 538-544 ◽

Cited By ~ 22

Author(s):

Y. B. Lee ◽

R. G. Kauffman

Keyword(s):

Adipose Tissue ◽

Enzyme Activities ◽

Lipogenic Enzyme ◽

Intramuscular Adipose Tissue

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Fatty acid elongation and desaturation enzyme activities of bovine liver and subcutaneous adipose tissue microsomes.

Journal of Animal Science ◽

10.2527/1991.6931064x ◽

1991 ◽

Vol 69 (3) ◽

pp. 1064 ◽

Cited By ~ 93

Author(s):

L C St John ◽

D K Lunt ◽

S B Smith

Keyword(s):

Adipose Tissue ◽

Fatty Acid ◽

Enzyme Activities ◽

Subcutaneous Adipose Tissue ◽

Bovine Liver ◽

Fatty Acid Elongation ◽

Subcutaneous Adipose

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Subcellular fractionation of brown adipose tissue

Journal of Supramolecular Structure ◽

10.1002/jss.400110403 ◽

1979 ◽

Vol 11 (4) ◽

pp. 445-449 ◽

Cited By ~ 10

Author(s):

J.-P. Giacobino

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Subcellular Fractionation ◽

Brown Adipose

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Lipogenic Enzymes of Rat Liver and Adipose Tissue. Dietary Variations and Effect of Polychlorinated Biphenyls

Zeitschrift für Naturforschung C ◽

10.1515/znc-1994-9-1018 ◽

1994 ◽

Vol 49 (9-10) ◽

pp. 665-678 ◽

Cited By ~ 3

Author(s):

Meinrad Boll ◽

Lutz W. D. Weber ◽

Andreas Stampfl ◽

Burkhard Messner

Keyword(s):

Adipose Tissue ◽

Polychlorinated Biphenyls ◽

Enzyme Activities ◽

Time Course ◽

Fatty Acid Synthase ◽

Lipogenic Enzymes ◽

Brown Adipose ◽

Cleavage Enzyme ◽

Order Of Magnitude ◽

Glucose 6 Phosphate Dehydrogenase

Abstract The lipogenic enzymes fatty acid synthase (FAS; EC 2.3.1.85), citrate cleavage enzyme (CCE; 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 dehydrogenase (PGDH; EC 1.1.1.44) were investigated in liver and in brown adipose tissue (BAT) of Wistar rats under various dietary conditions and in the presence of 15 to 250 ppm (approximately 0.045-0.75 μmol/kg chow) polychlorinated biphenyls (PCBs).In response to refeeding starved animals, enzyme activities in both tissues increased to above normal levels and thereafter exhibited pronounced oscillations of their activities. The extent of increase depended on the carbohydrate and fat content of the diet. The lipogenic enzymes could be grouped in two categories according to their sensitivity to dietary carbohydrate: FAS and CCE responded faster to smaller changes in dietary composition, while ME, G6PDH and PGDH required larger changes and more time to respond.Diet-induced alterations of enzyme activities were of the same order of magnitude in liver and BAT. They were age-dependent, being more pronounced in young animals. Independent of the type of dietary manipulations, activities changed in a coordinate fashion, i.e., the changes of the activities of all 5 enzymes occurred at similar ratios to each other with an identical time course.Feeding PCB-containing diets resulted in a considerable increase of the activities of the lipogenic enzymes in liver, which was significantly greater with ME, G 6PD H and PGDH. The effect was dose-dependent but transient. In liver the response to PCB feeding was identical in male and female animals, whereas in BAT lipogenic activities increased in females, but decreased in males.Refeeding starved animals with a PCB-containing diet led to an additional stimulation of the normal refeeding-induced increase of the enzyme activities in liver and BAT. This PCB-induced increase was 2-fold for FAS and CCE, but up to 15-fold for the other enzymes. All PCB-induced effects were significantly less pronounced in old than in young animals.In primary hepatocytes activities increased in hormone-free medium in the presence of PCBs. While activity was induced in insuline-and triiodothyronine-containing medium, this increase was significantly greater with PCBs present.

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Aquaporin-11 Contributes to TGF-β1-induced Endoplasmic Reticulum Stress in Human Visceral Adipocytes: Role in Obesity-Associated Inflammation

Cells ◽

10.3390/cells9061403 ◽

2020 ◽

Vol 9 (6) ◽

pp. 1403 ◽

Cited By ~ 1

Author(s):

Gema Frühbeck ◽

Inmaculada Balaguer ◽

Leire Méndez-Giménez ◽

Víctor Valentí ◽

Sara Becerril ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Adipose Tissue ◽

Er Stress ◽

Subcutaneous Fat ◽

Subcellular Fractionation ◽

Normal Weight ◽

Compensatory Mechanism ◽

Tissue Samples ◽

Water Glycerol ◽

Tgf Β1

Aquaporin-11 (AQP11) is expressed in human adipocytes, but its functional role remains unknown. Since AQP11 is an endoplasmic reticulum (ER)-resident protein that transports water, glycerol, and hydrogen peroxide (H2O2), we hypothesized that this superaquaporin is involved in ER stress induced by lipotoxicity and inflammation in human obesity. AQP11 expression was assessed in 67 paired visceral and subcutaneous adipose tissue samples obtained from patients with morbid obesity and normal-weight individuals. We found that obesity and obesity-associated type 2 diabetes increased (p < 0.05) AQP11 mRNA and protein in visceral adipose tissue, but not subcutaneous fat. Accordingly, AQP11 mRNA was upregulated (p < 0.05) during adipocyte differentiation and lipolysis, two biological processes altered in the obese state. Subcellular fractionation and confocal microscopy studies confirmed its presence in the ER plasma membrane of visceral adipocytes. Proinflammatory factors TNF-α, and particularly TGF-β1, downregulated (p < 0.05) AQP11 mRNA and protein expression and reinforced its subcellular distribution surrounding lipid droplets. Importantly, the AQP11 gene knockdown increased (p < 0.05) basal and TGF-β1-induced expression of the ER markers ATF4 and CHOP. Together, the downregulation of AQP11 aggravates TGF-β1-induced ER stress in visceral adipocytes. Owing to its “peroxiporin” properties, AQP11 overexpression in visceral fat might constitute a compensatory mechanism to alleviate ER stress in obesity.

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Effects of Ca2+ and Mg2+ on the activity of pyruvate dehydrogenase phosphate phosphatase within toluene-permeabilized mitochondria

Biochemical Journal ◽

10.1042/bj2410371 ◽

1987 ◽

Vol 241 (2) ◽

pp. 371-377 ◽

Cited By ~ 18

Author(s):

P J Midgley ◽

G A Rutter ◽

A P Thomas ◽

R M Denton

Keyword(s):

Adipose Tissue ◽

Small Molecules ◽

White Adipose Tissue ◽

Pyruvate Dehydrogenase ◽

Maximum Rate ◽

Major Effect ◽

Lag Phase ◽

Inhibitory Effects ◽

Highly Sensitive ◽

Epididymal White Adipose Tissue

Mitochondria from rat epididymal white adipose tissue were made permeable to small molecules by toluene treatment and were used to investigate the effects of Mg2+ and Ca2+ on the re-activation of pyruvate dehydrogenase phosphate by endogenous phosphatase. Re-activation of fully phosphorylated enzyme after addition of 0.18 mM-Mg2+ showed a marked lag of 5-10 min before a maximum rate of reactivation was achieved. Increasing the Mg2+ concentration to 1.8 mM (near saturating) or the addition of 100 microM-Ca2+ resulted in loss of the lag phase, which was also greatly diminished if pyruvate dehydrogenase was not fully phosphorylated. It is concluded that, within intact mitochondria, phosphatase activity is highly sensitive to the degree of phosphorylation of pyruvate dehydrogenase and that the major effect of Ca2+ may be to overcome the inhibitory effects of sites 2 and 3 on the dephosphorylation of site 1. Apparent K0.5 values for Mg2+ and Ca2+ were determined from the increases in pyruvate dehydrogenase activity observed after 5 min. The K0.5 for Mg2+ was diminished from 0.60 mM at less than 1 nM-Ca2+ to 0.32 mM at 100 microM-Ca2+; at 0.18 mM-Mg2+, the K0.5 for Ca2+ was 0.40 microM. Ca2+ had little or no effect at saturating Mg2+ concentrations. Since effects of Ca2+ are readily observed in intact coupled mitochondria, it follows that Mg2+ concentrations within mitochondria are sub-saturating for pyruvate dehydrogenase phosphate phosphatase and hence less than 0.5 mM.

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