Nejvíce citovaný článek - PubMed ID 25311170
Lipid signaling in adipose tissue: Connecting inflammation & metabolism
INTRODUCTION: Non-alcoholic fatty liver disease (NAFLD) can progress to more severe stages, such as steatohepatitis and fibrosis. Thermoneutral housing together with high-fat diet promoted NAFLD progression in C57BL/6J mice. Due to possible differences in steatohepatitis development between different C57BL/6 substrains, we examined how thermoneutrality affects NAFLD progression in C57BL/6N mice. METHODS: Male mice were fed standard or high-fat diet for 24 weeks and housed under standard (22°C) or thermoneutral (30°C) conditions. RESULTS: High-fat feeding promoted weight gain and hepatic steatosis, but the effect of thermoneutral environment was not evident. Liver expression of inflammatory markers was increased, with a modest and inconsistent effect of thermoneutral housing; however, histological scores of inflammation and fibrosis were generally low (<1.0), regardless of ambient temperature. In standard diet-fed mice, thermoneutrality increased weight gain, adiposity, and hepatic steatosis, accompanied by elevated de novo lipogenesis and changes in liver metabolome characterized by complex decreases in phospholipids and metabolites involved in urea cycle and oxidative stress defense. CONCLUSION: Thermoneutrality appears to promote NAFLD-associated phenotypes depending on the C57BL/6 substrain and/or the amount of dietary fat.
- Klíčová slova
- C57BL/6N mice, NASH, de novo lipogenesis, liver steatosis, metabolomics, non-alcoholic fatty liver disease, obesity, thermoneutrality,
- MeSH
- bydlení MeSH
- dieta s vysokým obsahem tuků škodlivé účinky MeSH
- hmotnostní přírůstek MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nealkoholová steatóza jater * metabolismus MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Obesity is associated with enhanced inflammation. However, investigation in human subcutaneous white adipose tissue (scWAT) is limited and the mechanisms by which inflammation occurs have not been well elucidated. Marine long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs) have anti-inflammatory actions and may reduce scWAT inflammation. METHODS: Subcutaneous white adipose tissue (scWAT) biopsies were collected from individuals living with obesity (n=45) and normal weight individuals (n=39) prior to and following a 12-week intervention with either 3 g/day of a fish oil concentrate (providing 1.1 g eicosapentaenoic acid (EPA) + 0.8 g docosahexaenoic acid (DHA)) or 3 g/day of corn oil. ScWAT fatty acid, oxylipin, and transcriptome profiles were assessed by gas chromatography, ultra-pure liquid chromatography tandem mass spectrometry, RNA sequencing and qRT-PCR, respectively. FINDINGS: Obesity was associated with greater scWAT inflammation demonstrated by lower concentrations of specialised pro-resolving mediators (SPMs) and hydroxy-DHA metabolites and an altered transcriptome with differential expression of genes involved in LC n-3 PUFA activation, oxylipin synthesis, inflammation, and immune response. Intervention with LC n-3 PUFAs increased their respective metabolites including the SPM precursor 14-hydroxy-DHA in normal weight individuals and decreased arachidonic acid derived metabolites and expression of genes involved in immune and inflammatory response with a greater effect in normal weight individuals. INTERPRETATION: Downregulated expression of genes responsible for fatty acid activation and metabolism may contribute to an inflammatory oxylipin profile and limit the effects of LC n-3 PUFAs in obesity. There may be a need for personalised LC n-3 PUFA supplementation based on obesity status. FUNDING: European Commission Seventh Framework Programme (Grant Number 244995) and Czech Academy of Sciences (Lumina quaeruntur LQ200111901).
- Klíčová slova
- Adipose tissue, Immune system, Inflammation, LC n-3 PUFA, Lipids, Obesity,
- MeSH
- bílá tuková tkáň metabolismus MeSH
- kyseliny dokosahexaenové MeSH
- lidé MeSH
- mastné kyseliny MeSH
- obezita farmakoterapie MeSH
- omega-3 mastné kyseliny * MeSH
- potravní doplňky * MeSH
- zánět metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- randomizované kontrolované studie MeSH
- Názvy látek
- kyseliny dokosahexaenové MeSH
- mastné kyseliny MeSH
- omega-3 mastné kyseliny * 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.
- Klíčová slova
- adipocytes, glucose homeostasis, insulin, lipogenesis, obesity,
- MeSH
- bílá tuková tkáň metabolismus MeSH
- dieta s vysokým obsahem tuků MeSH
- hypoglykemika 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
- omega-3 mastné kyseliny aplikace a dávkování farmakologie 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
- Názvy látek
- hypoglykemika MeSH
- mastné kyseliny MeSH
- omega-3 mastné kyseliny MeSH
- pioglitazon MeSH
- thiazolidindiony MeSH
- triglyceridy MeSH
BACKGROUND: Cachexia worsens long-term prognosis of patients with heart failure (HF). Effective treatment of cachexia is missing. We seek to characterize mechanisms of cachexia in adipose tissue, which could serve as novel targets for the treatment. METHODS: The study was conducted in advanced HF patients (n = 52; 83% male patients) undergoing heart transplantation. Patients with ≥7.5% non-intentional body weight (BW) loss during the last 6 months were rated cachectic. Clinical characteristics and circulating markers were compared between cachectic (n = 17) and the remaining, BW-stable patients. In epicardial adipose tissue (EAT), expression of selected genes was evaluated, and a combined metabolomic/lipidomic analysis was performed to assess (i) the role of adipose tissue metabolism in the development of cachexia and (ii) potential impact of cachexia-associated changes on EAT-myocardium environment. RESULTS: Cachectic vs. BW-stable patients had higher plasma levels of natriuretic peptide B (BNP; 2007 ± 1229 vs. 1411 ± 1272 pg/mL; P = 0.010) and lower EAT thickness (2.1 ± 0.8 vs. 2.9 ± 1.4 mm; P = 0.010), and they were treated with ~2.5-fold lower dose of both β-blockers and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACE/ARB-inhibitors). The overall pattern of EAT gene expression suggested simultaneous activation of lipolysis and lipogenesis in cachexia. Lower ratio between expression levels of natriuretic peptide receptors C and A was observed in cachectic vs. BW-stable patients (0.47 vs. 1.30), supporting activation of EAT lipolysis by natriuretic peptides. Fundamental differences in metabolome/lipidome between BW-stable and cachectic patients were found. Mitochondrial phospholipid cardiolipin (CL), specifically the least abundant CL 70:6 species (containing C16:1, C18:1, and C18:2 acyls), was the most discriminating analyte (partial least squares discriminant analysis; variable importance in projection score = 4). Its EAT levels were higher in cachectic as compared with BW-stable patients and correlated with the degree of BW loss during the last 6 months (r = -0.94; P = 0.036). CONCLUSIONS: Our results suggest that (i) BNP signalling contributes to changes in EAT metabolism in cardiac cachexia and (ii) maintenance of stable BW and 'healthy' EAT-myocardium microenvironment depends on the ability to tolerate higher doses of both ACE/ARB inhibitors and β-adrenergic blockers. In line with preclinical studies, we show for the first time in humans the association of cachexia with increased adipose tissue levels of CL. Specifically, CL 70:6 could precipitate wasting of adipose tissue, and thus, it could represent a therapeutic target to ameliorate cachexia.
- Klíčová slova
- Adipose tissue, Cardiac cachexia, Cardiolipin, Heart failure, Lipolysis, Natriuretic peptides,
- MeSH
- antagonisté receptorů pro angiotenzin MeSH
- inhibitory ACE MeSH
- kachexie * etiologie MeSH
- kardiolipiny MeSH
- lidé MeSH
- natriuretické peptidy MeSH
- srdeční selhání * komplikace MeSH
- tuková tkáň * MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- antagonisté receptorů pro angiotenzin MeSH
- inhibitory ACE MeSH
- kardiolipiny MeSH
- natriuretické peptidy MeSH
Branched esters of palmitic acid and hydroxystearic acid (PAHSA) are anti-inflammatory and antidiabetic lipokines that connect glucose and lipid metabolism. We aimed to characterize involvement of the 5-PAHSA regioisomer in the adaptive metabolic response of white adipose tissue (WAT) to cold exposure (CE) in mice, exploring the cross talk between glucose utilization and lipid metabolism. CE promoted local production of 5- and 9-PAHSAs in WAT. Metabolic labeling of de novo lipogenesis (DNL) using 2H2O revealed that 5-PAHSA potentiated the effects of CE and stimulated triacylglycerol (TAG)/fatty acid (FA) cycling in WAT through impacting lipogenesis and lipolysis. Adipocyte lipolytic products were altered by 5-PAHSA through selective FA re-esterification. The impaired lipolysis in global adipose triglyceride lipase (ATGL) knockout mice reduced free PAHSA levels and uncovered a metabolite reservoir of TAG-bound PAHSAs (TAG estolides) in WAT. Utilization of 13C isotope tracers and dynamic metabolomics documented that 5-PAHSA primes adipocytes for glucose metabolism in a different way from insulin, promoting DNL and impeding TAG synthesis. In summary, our data reveal new cellular and physiological mechanisms underlying the beneficial effects of 5-PAHSA and its relation to insulin action in adipocytes and independently confirm a PAHSA metabolite reservoir linked to ATGL-mediated lipolysis.
- MeSH
- bílá tuková tkáň metabolismus MeSH
- glukosa metabolismus MeSH
- izotopy uhlíku MeSH
- kyselina palmitová metabolismus MeSH
- kyseliny stearové metabolismus MeSH
- lipasa genetika metabolismus MeSH
- lipogeneze genetika MeSH
- lipolýza MeSH
- mastné kyseliny metabolismus MeSH
- metabolomika MeSH
- myši knockoutované MeSH
- myši MeSH
- nízká teplota MeSH
- oxid deuteria MeSH
- triglyceridy metabolismus MeSH
- tukové buňky metabolismus MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- 5-PAHSA MeSH Prohlížeč
- 9-PAHSA MeSH Prohlížeč
- glukosa MeSH
- izotopy uhlíku MeSH
- kyselina palmitová MeSH
- kyseliny stearové MeSH
- lipasa MeSH
- mastné kyseliny MeSH
- oxid deuteria MeSH
- PNPLA2 protein, mouse MeSH Prohlížeč
- triglyceridy MeSH
We found previously that white adipose tissue (WAT) hyperplasia in obese mice was limited by dietary omega-3 polyunsaturated fatty acids (omega-3 PUFA). Here we aimed to characterize the underlying mechanism. C57BL/6N mice were fed a high-fat diet supplemented or not with omega-3 PUFA for one week or eight weeks; mice fed a standard chow diet were also used. In epididymal WAT (eWAT), DNA content was quantified, immunohistochemical analysis was used to reveal the size of adipocytes and macrophage content, and lipidomic analysis and a gene expression screen were performed to assess inflammatory status. The stromal-vascular fraction of eWAT, which contained most of the eWAT cells, except for adipocytes, was characterized using flow cytometry. Omega-3 PUFA supplementation limited the high-fat diet-induced increase in eWAT weight, cell number (DNA content), inflammation, and adipocyte growth. eWAT hyperplasia was compromised due to the limited increase in the number of preadipocytes and a decrease in the number of endothelial cells. The number of leukocytes and macrophages was unaffected, but a shift in macrophage polarization towards a less inflammatory phenotype was observed. Our results document that the counteraction of eWAT hyperplasia by omega-3 PUFA in dietary-obese mice reflects an effect on the number of adipose lineage and endothelial cells.
- Klíčová slova
- adipocyte, cellularity, fat, nutrition, obesity, proliferation, white adipose tissue,
- MeSH
- bílá tuková tkáň účinky léků MeSH
- dieta s vysokým obsahem tuků MeSH
- endoteliální buňky účinky léků MeSH
- makrofágy účinky léků patologie MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- omega-3 mastné kyseliny aplikace a dávkování MeSH
- proliferace buněk účinky léků MeSH
- tukové buňky cytologie účinky léků MeSH
- zánět patologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- omega-3 mastné kyseliny MeSH
Fatty acid esters of hydroxy fatty acids (FAHFAs) are lipid mediators with promising antidiabetic and anti-inflammatory properties that are formed in white adipose tissue (WAT) via de novo lipogenesis, but their biosynthetic enzymes are unknown. Using a combination of lipidomics in WAT, quantitative trait locus mapping, and correlation analyses in rat BXH/HXB recombinant inbred strains, as well as response to oxidative stress in murine models, we elucidated the potential pathway of biosynthesis of several FAHFAs. Comprehensive analysis of WAT samples identified ∼160 regioisomers, documenting the complexity of this lipid class. The linkage analysis highlighted several members of the nuclear factor, erythroid 2 like 2 (Nrf2)-mediated antioxidant defense system (Prdx6, Mgst1, Mgst3), lipid-handling proteins (Cd36, Scd6, Acnat1, Acnat2, Baat), and the family of flavin containing monooxygenases (Fmo) as the positional candidate genes. Transgenic expression of Nrf2 and deletion of Prdx6 genes resulted in reduction of palmitic acid ester of 9-hydroxystearic acid (9-PAHSA) and 11-PAHSA levels, while oxidative stress induced by an inhibitor of glutathione synthesis increased PAHSA levels nonspecifically. Our results indicate that the synthesis of FAHFAs via carbohydrate-responsive element-binding protein-driven de novo lipogenesis depends on the adaptive antioxidant system and suggest that FAHFAs may link activity of this system with insulin sensitivity in peripheral tissues.
- MeSH
- bílá tuková tkáň enzymologie metabolismus MeSH
- biologické markery metabolismus MeSH
- estery chemie metabolismus MeSH
- faktor 2 související s NF-E2 genetika metabolismus MeSH
- krysa rodu Rattus MeSH
- kyselina palmitová chemie metabolismus MeSH
- kyseliny stearové chemie metabolismus MeSH
- metabolomika metody MeSH
- myši inbrední C57BL MeSH
- myši knockoutované MeSH
- náhodné rozdělení MeSH
- oxidační stres * MeSH
- peroxiredoxin VI genetika metabolismus MeSH
- potkani inbrední BN MeSH
- potkani inbrední SHR MeSH
- potkani transgenní MeSH
- regulace genové exprese enzymů * MeSH
- stanovení celkové genové exprese MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- 9-hydroxystearic acid MeSH Prohlížeč
- biologické markery MeSH
- estery MeSH
- faktor 2 související s NF-E2 MeSH
- kyselina palmitová MeSH
- kyseliny stearové MeSH
- Nfe2l2 protein, mouse MeSH Prohlížeč
- Nfe2l2 protein, rat MeSH Prohlížeč
- peroxiredoxin VI MeSH
- Prdx6 protein, mouse MeSH Prohlížeč