The molecular mechanisms linking obstructive sleep apnea syndrome (OSA) to obesity and the development of metabolic diseases are still poorly understood. The role of hypoxia (a characteristic feature of OSA) in excessive fat accumulation has been proposed. The present study investigated the possible effects of hypoxia (4% oxygen) on de novo lipogenesis by tracking the major carbon sources in differentiating 3T3-L1 adipocytes. Gas-permeable cultuware was employed to cultivate 3T3-L1 adipocytes in hypoxia (4%) for 7 or 14 days of differentiation. We investigated the contribution of glutamine, glucose or acetate using 13C or 14C labelled carbons to the newly synthesized lipid pool, changes in intracellular lipid content after inhibiting citrate- or acetate-dependent pathways and gene expression of involved key enzymes. The results demonstrate that, in differentiating adipocytes, hypoxia decreased the synthesis of lipids from glucose (44.1 ± 8.8 to 27.5 ± 3.0 pmol/mg of protein, p < 0.01) and partially decreased the contribution of glutamine metabolized through the reverse tricarboxylic acid cycle (4.6% ± 0.2-4.2% ± 0.1%, p < 0.01). Conversely, the contribution of acetate, a citrate- and mitochondria-independent source of carbons, increased upon hypoxia (356.5 ± 71.4 to 649.8 ± 117.5 pmol/mg of protein, p < 0.01). Further, inhibiting the citrate- or acetate-dependent pathways decreased the intracellular lipid content by 58% and 73%, respectively (p < 0.01) showing the importance of de novo lipogenesis in hypoxia-exposed adipocytes. Altogether, hypoxia modified the utilization of carbon sources, leading to alterations in de novo lipogenesis in differentiating adipocytes and increased intracellular lipid content.

• MeSH
• acetáty * metabolismus   farmakologie   MeSH
• buněčná diferenciace * účinky léků   MeSH
• buňky 3T3-L1 * MeSH
• citrátový cyklus MeSH
• glukosa * metabolismus   MeSH
• glutamin * metabolismus   MeSH
• hypoxie buňky MeSH
• lipidy biosyntéza   MeSH
• lipogeneze * účinky léků   MeSH
• metabolismus lipidů účinky léků   MeSH
• myši MeSH
• tukové buňky * metabolismus   účinky léků   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Cylindrospermopsin, a potent hepatotoxin produced by harmful cyanobacterial blooms, poses environmental and human health concerns. We used a 3D human liver in vitro model based on spheroids of HepG2 cells, in combination with molecular and biochemical assays, automated imaging, targeted LC-MS-based proteomics, and lipidomics, to explore cylindrospermopsin effects on lipid metabolism and the processes implicated in hepatic steatosis. Cylindrospermopsin (1 μM, 48 h) did not significantly affect cell viability but partially reduced albumin secretion. However, it increased neutral lipid accumulation in HepG2 spheroids while decreasing phospholipid levels. Simultaneously, cylindrospermopsin upregulated genes for lipogenesis regulation (SREBF1) and triacylglycerol synthesis (DGAT1/2) and downregulated genes for fatty acid synthesis (ACLY, ACCA, FASN, SCD1). Fatty acid uptake, oxidation, and lipid efflux genes were not significantly affected. Targeted proteomics revealed increased levels of perilipin 2 (adipophilin), a major hepatocyte lipid droplet-associated protein. Lipid profiling quantified 246 lipid species in the spheroids, with 28 significantly enriched and 15 downregulated by cylindrospermopsin. Upregulated species included neutral lipids, sphingolipids (e.g., ceramides and dihexosylceramides), and some glycerophospholipids (phosphatidylethanolamines, phosphatidylserines), while phosphatidylcholines and phosphatidylinositols were mostly reduced. It suggests that cylindrospermopsin exposures might contribute to developing and progressing towards hepatic steatosis or metabolic dysfunction-associated steatotic liver disease (MASLD).

• MeSH
• alkaloidy * farmakologie   MeSH
• bakteriální toxiny * metabolismus   MeSH
• buněčné sféroidy účinky léků   metabolismus   MeSH
• buňky Hep G2 MeSH
• homeostáza účinky léků   MeSH
• játra * metabolismus   účinky léků   MeSH
• lidé MeSH
• lipidomika MeSH
• lipogeneze účinky léků   MeSH
• metabolismus lipidů * účinky léků   MeSH
• proteomika MeSH
• toxiny kmene Cyanobacteria * MeSH
• uracil * analogy a deriváty   metabolismus   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

(1) Background: empagliflozin, sodium-glucose co-transporter 2 (SGLT-2) inhibitor, is an effective antidiabetic agent with strong cardio- and nephroprotective properties. The mechanisms behind its cardio- and nephroprotection are still not fully clarified. (2) Methods: we used male hereditary hypertriglyceridemic (hHTG) rats, a non-obese model of dyslipidaemia, insulin resistance, and endothelial dysfunction fed standard diet with or without empagliflozin for six weeks to explore the molecular mechanisms of empagliflozin effects. Nuclear magnetic resonance (NMR)-based metabolomics; quantitative PCR of relevant genes involved in lipid and glucose metabolism, or senescence; glucose and palmitic acid oxidation in isolated tissues and cell lines of adipocytes and hepatocytes were used. (3) Results: empagliflozin inhibited weight gain and decreased adipose tissue weight, fasting blood glucose, and triglycerides and increased HDL-cholesterol. It also improved insulin sensitivity in white fat. NMR spectroscopy identified higher plasma concentrations of ketone bodies, ketogenic amino acid leucine and decreased levels of pyruvate and alanine. In the liver, adipose tissue and kidney, empagliflozin up-regulated expression of genes involved in gluconeogenesis and down-regulated expression of genes involved in lipogenesis along with reduction of markers of inflammation, oxidative stress and cell senescence. (4) Conclusion: multiple positive effects of empagliflozin, including reduced cell senescence and oxidative stress, could contribute to its long-term cardio- and nephroprotective actions.

• MeSH
• aplikace orální MeSH
• benzhydrylové sloučeniny aplikace a dávkování   MeSH
• buňky 3T3-L1 MeSH
• buňky Hep G2 MeSH
• down regulace účinky léků   MeSH
• dyslipidemie farmakoterapie   MeSH
• glifloziny aplikace a dávkování   MeSH
• glukoneogeneze účinky léků   genetika   MeSH
• glukosidy aplikace a dávkování   MeSH
• hmotnostní přírůstek účinky léků   MeSH
• hypertriglyceridemie farmakoterapie   metabolismus   MeSH
• hypoglykemika aplikace a dávkování   MeSH
• inzulinová rezistence MeSH
• játra metabolismus   MeSH
• krysa rodu rattus MeSH
• ledviny metabolismus   MeSH
• lidé MeSH
• lipogeneze účinky léků   genetika   MeSH
• modely nemocí na zvířatech MeSH
• myši MeSH
• oxidační stres účinky léků   MeSH
• stárnutí buněk účinky léků   MeSH
• tuková tkáň metabolismus   MeSH
• upregulace účinky léků   MeSH
• viabilita buněk účinky léků   MeSH
• výsledek terapie MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Ovarian hormone deficiency leads to increased body weight, visceral adiposity, fatty liver and disorders associated with menopausal metabolic syndrome. To better understand the underlying mechanisms of these disorders in their early phases of development, we investigated the effect of ovariectomy on lipid and glucose metabolism. Compared to sham-operated controls, ovariectomized Wistar female rats markedly increased whole body and visceral adipose tissue weight (p ˂ 0.05) and exhibited insulin resistance in peripheral tissues. Severe hepatic triglyceride accumulation (p ˂ 0.001) after ovariectomy preceded changes in both serum lipids and glucose intolerance, reflecting alterations in some CYP proteins. Increased CYP2E1 (p ˂ 0.05) and decreased CYP4A (p ˂ 0.001) after ovariectomy reduced fatty acid oxidation and induced hepatic steatosis. Decreased triglyceride metabolism and secretion from the liver contributed to hepatic triglyceride accumulation in response to ovariectomy. In addition, interscapular brown adipose tissue of ovariectomized rats exhibited decreased fatty acid oxidation (p ˂ 0.01), lipogenesis (p ˂ 0.05) and lipolysis (p ˂ 0.05) despite an increase in tissue weight. The results provide evidence that impaired hepatic triglycerides and dysregulation of some CYP450 proteins may have been involved in the development of hepatic steatosis. The low metabolic activity of brown adipose tissue may have contributed to visceral adiposity as well as triglyceride accumulation during the postmenopausal period.

• MeSH
• bílá tuková tkáň metabolismus   MeSH
• dieta s vysokým obsahem tuků MeSH
• dyslipidemie metabolismus   MeSH
• glukosa metabolismus   MeSH
• hmotnostní přírůstek MeSH
• hnědá tuková tkáň metabolismus   MeSH
• inzulin metabolismus   MeSH
• inzulinová rezistence MeSH
• játra metabolismus   MeSH
• krysa rodu rattus MeSH
• lipidy krev   MeSH
• lipogeneze účinky léků   MeSH
• lipolýza MeSH
• menopauza metabolismus   fyziologie   MeSH
• metabolismus lipidů účinky léků   fyziologie   MeSH
• nitrobřišní tuk metabolismus   MeSH
• obezita metabolismus   MeSH
• ovarektomie škodlivé účinky   MeSH
• poruchy metabolismu lipidů etiologie   patofyziologie   MeSH
• postmenopauza metabolismus   fyziologie   MeSH
• potkani Wistar MeSH
• systém (enzymů) cytochromů P-450 metabolismus   fyziologie   MeSH
• triglyceridy metabolismus   MeSH
• ztučnělá játra metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Long-chain n-3 polyunsaturated fatty acids (Omega-3) and anti-diabetic drugs thiazolidinediones (TZDs) exhibit additive effects in counteraction of dietary obesity and associated metabolic dysfunctions in mice. The underlying mechanisms need to be clarified. Here, we aimed to learn whether the futile cycle based on the hydrolysis of triacylglycerol and re-esterification of fatty acids (TAG/FA cycling) in white adipose tissue (WAT) could be involved. We compared Omega-3 (30 mg/g diet) and two different TZDs-pioglitazone (50 mg/g diet) and a second-generation TZD, MSDC-0602K (330 mg/g diet)-regarding their effects in C57BL/6N mice fed an obesogenic high-fat (HF) diet for 8 weeks. The diet was supplemented or not by the tested compound alone or with the two TZDs combined individually with Omega-3. Activity of TAG/FA cycle in WAT was suppressed by the obesogenic HF diet. Additive effects in partial rescue of TAG/FA cycling in WAT were observed with both combined interventions, with a stronger effect of Omega-3 and MSDC-0602K. Our results (i) supported the role of TAG/FA cycling in WAT in the beneficial additive effects of Omega-3 and TZDs on metabolism of diet-induced obese mice, and (ii) showed differential modulation of WAT gene expression and metabolism by the two TZDs, depending also on Omega-3.

• MeSH
• bílá tuková tkáň metabolismus   MeSH
• dieta s vysokým obsahem tuků MeSH
• hypoglykemika farmakologie   MeSH
• kyseliny mastné omega-3 aplikace a dávkování   farmakologie   MeSH
• lipogeneze účinky léků   MeSH
• mastné kyseliny metabolismus   MeSH
• metabolismus lipidů účinky léků   MeSH
• myši inbrední C57BL MeSH
• myši obézní MeSH
• myši MeSH
• obezita farmakoterapie   metabolismus   MeSH
• pioglitazon farmakologie   MeSH
• thiazolidindiony aplikace a dávkování   farmakologie   MeSH
• triglyceridy metabolismus   MeSH
• tukové buňky účinky léků   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Saturated fatty acid (SFA) intake is associated with obesity, insulin resistance, and hepatic steatosis, but scant work examines the impact of SFA type upon these outcomes. We tested the hypothesis that an obesogenic diet prepared with medium chain SFA (MCSFA), mostly as lauric acid-derived from coconut oil, reduces obesity-induced outcomes compared to obesogenic diets prepared with increasing amounts long chain SFA (LCSFA), primarily palmitic acid. Mice were fed (16 weeks) a control, low fat diet or obesogenic diets prepared with differing content of MCSFA or LCSFA in which polyunsaturated and monounsaturated fatty acids (PUFA; MUFA) were kept constant. Inclusion of MCSFA in an obesogenic diet prevented hepatic lipid accumulation and lowered indices of insulin resistance. Obesogenic diets reduced hepatic levels of de novo lipogenesis proteins (SCD1 and FASN) but elevated the adipose levels of mRNA for the pro-inflammatory markers Mcp-1 and Tnfα. Lipidomic analysis of plasma indicated that MCSFA intake resulted in a different lipidomic signature than LCSFA intake, prevented elevation of pro-inflammatory ceramides, but elevated concentrations of some lipids associated with elevated cardiovascular disease risk. Intake of the obesogenic diets in an SFA-type dependent manner elevated plasma concentrations of several phosphatidylcholine (PC) lipids having the long chain PUFA (LCPUFA) arachidonic acid (ARA) and docosahexaenoic acid (DHA), altered phospholipid ethers, and changed the triacylglyceryl environments of these LCPUFA. Our data indicate that (1) MCSFA reduce the severity of some obesogenic co-morbidities, (2) SFA-type modulates lipidomic signatures associated with cardiovascular disease and diabetes, and (3) dietary SFA type impacts LCPUFA metabolism.

• MeSH
• ceramidy metabolismus   MeSH
• hepatitida etiologie   MeSH
• inzulinová rezistence MeSH
• kyseliny mastné mononenasycené farmakologie   MeSH
• lipidy krev   MeSH
• lipogeneze účinky léků   MeSH
• mastné kyseliny chemie   metabolismus   farmakologie   MeSH
• myši inbrední C57BL MeSH
• obezita etiologie   metabolismus   MeSH
• panniculitis etiologie   prevence a kontrola   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

The constitutive androstane receptor(CAR) activation is connected with mitogenic effects leading to liver hyperplasia and tumorigenesis in rodents. CAR activators, including phenobarbital, are considered rodent non-genotoxic carcinogens. Recently, trans-3,4,5,4´-tetramethoxystilbene(TMS), a potential anticancer drug (DMU-212), have been shown to alleviate N-nitrosodiethylamine/phenobarbital-induced liver carcinogenesis. We studied whether TMS inhibits mouse Car to protect from the PB-induced tumorigenesis. Unexpectedly, we identified TMS as a murine CAR agonist in reporter gene experiments, in mouse hepatocytes, and in C57BL/6 mice in vivo. TMS up-regulated Car target genes Cyp2b10, Cyp2c29 and Cyp2c55 mRNAs, but down-regulated expression of genes involved in gluconeogenesis and lipogenesis. TMS did not change or down-regulate genes involved in liver proliferation or apoptosis such as Mki67, Foxm1, Myc, Mcl1, Pcna, Bcl2, or Mdm2, which were up-regulated by another Car ligand TCPOBOP. TMS did not increase liver weight and had no significant effect on Ki67 and Pcna labeling indices in mouse liver in vivo. In murine hepatic AML12 cells, we confirmed a Car-independent proapoptotic effect of TMS. We conclude that TMS is a Car ligand with limited effects on hepatocyte proliferation, likely due to promoting apoptosis in mouse hepatic cells, while controlling Car target genes involved in xenobiotic and endobiotic metabolism.

• MeSH
• antikarcinogenní látky metabolismus   farmakologie   MeSH
• apoptóza účinky léků   MeSH
• aromatické hydroxylasy genetika   metabolismus   MeSH
• buňky Hep G2 MeSH
• glukoneogeneze účinky léků   genetika   MeSH
• hepatocyty účinky léků   metabolismus   patologie   MeSH
• játra účinky léků   metabolismus   MeSH
• lidé MeSH
• lipogeneze účinky léků   genetika   MeSH
• myši inbrední C57BL MeSH
• nádory jater enzymologie   genetika   patologie   prevence a kontrola   MeSH
• proliferace buněk účinky léků   MeSH
• pyridiny farmakologie   MeSH
• receptory cytoplazmatické a nukleární agonisté   genetika   metabolismus   MeSH
• regulace genové exprese enzymů účinky léků   MeSH
• rodina 2 cytochromů P450 genetika   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• simulace molekulového dockingu MeSH
• steroidhydroxylasy genetika   metabolismus   MeSH
• stilbeny metabolismus   farmakologie   MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• biomedicínský výzkum metody   trendy   MeSH
• desaturasy mastných kyselin antagonisté a inhibitory   metabolismus   terapeutické užití   MeSH
• diabetes mellitus enzymologie   metabolismus   MeSH
• kyseliny mastné mononenasycené izolace a purifikace   metabolismus   MeSH
• lidé MeSH
• lipogeneze genetika   imunologie   účinky léků   MeSH
• metabolické nemoci * enzymologie   metabolismus   MeSH
• nádory * enzymologie   metabolismus   MeSH
• statistika jako téma MeSH
• stearyl-CoA-desaturasa * antagonisté a inhibitory   metabolismus   terapeutické užití   MeSH
• triglyceridy izolace a purifikace   metabolismus   MeSH
• Check Tag
• lidé MeSH

Cachexia represents a fatal energy-wasting syndrome in a large number of patients with cancer that mostly results in a pathological loss of skeletal muscle and adipose tissue. Here we show that tumor cell exposure and tumor growth in mice triggered a futile energy-wasting cycle in cultured white adipocytes and white adipose tissue (WAT), respectively. Although uncoupling protein 1 (Ucp1)-dependent thermogenesis was dispensable for tumor-induced body wasting, WAT from cachectic mice and tumor-cell-supernatant-treated adipocytes were consistently characterized by the simultaneous induction of both lipolytic and lipogenic pathways. Paradoxically, this was accompanied by an inactivated AMP-activated protein kinase (Ampk), which is normally activated in peripheral tissues during states of low cellular energy. Ampk inactivation correlated with its degradation and with upregulation of the Ampk-interacting protein Cidea. Therefore, we developed an Ampk-stabilizing peptide, ACIP, which was able to ameliorate WAT wasting in vitro and in vivo by shielding the Cidea-targeted interaction surface on Ampk. Thus, our data establish the Ucp1-independent remodeling of adipocyte lipid homeostasis as a key event in tumor-induced WAT wasting, and we propose the ACIP-dependent preservation of Ampk integrity in the WAT as a concept in future therapies for cachexia.

• MeSH
• bílá tuková tkáň účinky léků   metabolismus   MeSH
• bílé tukové buňky účinky léků   metabolismus   MeSH
• kachexie etiologie   metabolismus   MeSH
• kultivované buňky MeSH
• lipogeneze účinky léků   MeSH
• lipolýza účinky léků   MeSH
• metabolismus lipidů účinky léků   MeSH
• myši MeSH
• nádory komplikace   metabolismus   MeSH
• peptidové fragmenty farmakologie   MeSH
• proteinkinasy aktivované AMP metabolismus   farmakologie   MeSH
• proteiny regulující apoptózu účinky léků   metabolismus   MeSH
• techniky in vitro MeSH
• termogeneze účinky léků   MeSH
• uncoupling protein 1 účinky léků   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

In-vitro investigation of the effects of hypoxia is limited by physical laws of gas diffusion and cellular O2 consumption, making prolonged exposures to stable O2 concentrations impossible. Using a gas-permeable cultureware, chronic effects of mild and severe hypoxia on triglyceride accumulation, lipid droplet size distribution, spontaneous lipolysis and gene expression of adipocyte-specific markers were assessed. 3T3-L1 cells were differentiated under 20%, 4% or 1% O2 using a gas-permeable cultureware. Triglyceride accumulation, expression of genes characteristic for advanced adipocyte differentiation and involvement of key lipogenesis enzymes were assessed after exposures. Lipogenesis increased by 375% under mild hypoxia, but dropped by 43% in severe hypoxia. Mild, but not severe, hypoxia increased formation of large lipid droplets 6.4 fold and strongly induced gene expression of adipocyte-specific markers. Spontaneous lipolysis increased by 488% in mild, but only by 135% in severe hypoxia. Inhibition of ATP-dependent citrate lyase suppressed hypoxia-induced lipogenesis by 81% and 85%. Activation of HIF inhibited lipogenesis by 59%. Mild, but not severe, hypoxia stimulates lipolysis and promotes adipocyte differentiation, probably through excess of acetyl-CoA originating from tricarboxylic acid cycle independently of HIF activation.

• MeSH
• acetylkoenzym A metabolismus   MeSH
• adipogeneze účinky léků   genetika   MeSH
• ATP-citrát-(pro-S)-lyasa genetika   metabolismus   MeSH
• buněčná diferenciace účinky léků   MeSH
• buňky 3T3-L1 MeSH
• citrátový cyklus účinky léků   genetika   MeSH
• diacylglycerol-O-acyltransferasa genetika   metabolismus   MeSH
• faktor 1 indukovatelný hypoxií - podjednotka alfa genetika   metabolismus   MeSH
• hypoxie buňky MeSH
• kyslík farmakologie   MeSH
• lipidová tělíska chemie   účinky léků   MeSH
• lipogeneze účinky léků   genetika   MeSH
• lipolýza účinky léků   genetika   MeSH
• myši MeSH
• perilipin 1 genetika   metabolismus   MeSH
• proteiny vázající mastné kyseliny genetika   metabolismus   MeSH
• regulace genové exprese účinky léků   MeSH
• signální transdukce MeSH
• sterolesterasa genetika   metabolismus   MeSH
• triglyceridy metabolismus   MeSH
• tukové buňky cytologie   účinky léků   metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH