Light pollution disturbs circadian rhythm, and this can also be deleterious to the heart by increased susceptibility to arrhythmias. Herein, we investigated if rats exposed to continuous light had altered myocardial gene transcripts and/or protein expression which affects arrhythmogenesis. We then assessed if Omacor® supplementation benefitted affected rats. Male and female spontaneously hypertensive (SHR) and normotensive Wistar rats (WR) were housed under standard 12 h/12 h light/dark cycles or exposed to 6-weeks continuous 300 lux light for 24 h. Half the rats were then treated with 200 mg/100 g b.w. Omacor®. Continuous light resulted in higher male rat vulnerability to malignant ventricular fibrillation (VF). This was linked with myocardial connexin-43 (Cx43) down-regulation and deteriorated intercellular electrical coupling, due in part to increased pro-inflammatory NF-κB and iNOS transcripts and decreased sarcoplasmic reticulum Ca2+ATPase transcripts. Omacor® treatment increased the electrical threshold to induce the VF linked with amelioration of myocardial Cx43 mRNA and Cx43 protein levels and the suppression of NF-κB and iNOS. This indicates that rat exposure to continuous light results in deleterious cardiac alterations jeopardizing intercellular Cx43 channel-mediated electrical communication, thereby increasing the risk of malignant arrhythmias. The adverse effects were attenuated by treatment with Omacor®, thus supporting its potential benefit and the relevance of monitoring omega-3 index in human populations at risk.

• Klíčová slova
• NF-κB, cardiac arrhythmias, connexin-43, iNOS, light pollution, omacor, rats,
• MeSH
• fixní kombinace léků MeSH
• fyziologický stres * MeSH
• hypertenze komplikace   MeSH
• konexin 43 metabolismus   MeSH
• krevní tlak účinky léků   MeSH
• krysa rodu Rattus MeSH
• kyselina eikosapentaenová aplikace a dávkování   chemie   farmakologie   MeSH
• kyseliny dokosahexaenové aplikace a dávkování   chemie   farmakologie   MeSH
• modely nemocí na zvířatech MeSH
• potkani inbrední SHR MeSH
• potkani Wistar MeSH
• potravní doplňky * MeSH
• srdce účinky léků   MeSH
• srdeční arytmie komplikace   patofyziologie   prevence a kontrola   MeSH
• světelné znečištění * MeSH
• vodní organismy MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fixní kombinace léků MeSH
• konexin 43 MeSH
• kyselina eikosapentaenová MeSH
• kyseliny dokosahexaenové MeSH
• Omacor MeSH Prohlížeč

Obesity is believed to be associated with a dysregulated endocannabinoid system which may reflect enhanced inflammation. However, reports of this in human white adipose tissue (WAT) are limited and inconclusive. Marine long-chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs) have anti-inflammatory actions and therefore may improve obesity-associated adipose tissue inflammation. Therefore, fatty acid (FA) concentrations, endocannabinoid concentrations, and gene expression were assessed in subcutaneous WAT (scWAT) biopsies from healthy normal weight individuals (BMI 18.5-25 kg/m2) and individuals living with metabolically healthy obesity (BMI 30-40 kg/m2) prior to and following a 12-week intervention with 3 g fish oil/day (1.1 g eicosapentaenoic acid (EPA) + 0.8 g DHA) or 3 g corn oil/day (placebo). WAT from individuals living with metabolically healthy obesity had higher n-6 PUFAs and EPA, higher concentrations of two endocannabinoids (anandamide (AEA) and eicosapentaenoyl ethanolamide (EPEA)), higher expression of phospholipase A2 Group IID (PLA2G2D) and phospholipase A2 Group IVA (PLA2G4A), and lower expression of CNR1. In response to fish oil intervention, WAT EPA increased to a similar extent in both BMI groups, and WAT DHA increased by a greater extent in normal weight individuals. WAT EPEA and docosahexaenoyl ethanolamide (DHEA) increased in normal weight individuals only and WAT 2-arachidonyl glycerol (2-AG) decreased in individuals living with metabolically healthy obesity only. Altered WAT fatty acid, endocannabinoid, and gene expression profiles in metabolically healthy obesity at baseline may be linked. WAT incorporates n-3 PUFAs when their intake is increased which affects the endocannabinoid system; however, effects appear greater in normal weight individuals than in those living with metabolically healthy obesity.

• Klíčová slova
• LC n-3 PUFA, adipose tissue, endocannabinoids, lipids, obesity,
• MeSH
• časové faktory MeSH
• dospělí MeSH
• dvojitá slepá metoda MeSH
• endokanabinoidy metabolismus   MeSH
• fixní kombinace léků MeSH
• fosfolipasy A2, skupina II metabolismus   MeSH
• fosfolipasy A2, skupina IV metabolismus   MeSH
• kyselina eikosapentaenová aplikace a dávkování   MeSH
• kyseliny arachidonové metabolismus   MeSH
• kyseliny dokosahexaenové aplikace a dávkování   MeSH
• lidé středního věku MeSH
• lidé MeSH
• metabolicky zdravá obezita diagnóza   farmakoterapie   metabolismus   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• podkožní tuk účinky léků   metabolismus   MeSH
• polynenasycené alkamidy metabolismus   MeSH
• potravní doplňky * MeSH
• receptor kanabinoidní CB1 metabolismus   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Geografické názvy
• Anglie MeSH
• Názvy látek
• anandamide MeSH Prohlížeč
• CNR1 protein, human MeSH Prohlížeč
• endokanabinoidy MeSH
• fixní kombinace léků MeSH
• fosfolipasy A2, skupina II MeSH
• fosfolipasy A2, skupina IV MeSH
• kyselina eikosapentaenová MeSH
• kyseliny arachidonové MeSH
• kyseliny dokosahexaenové MeSH
• N-docosahexaenoylethanolamide MeSH Prohlížeč
• PLA2G2D protein, human MeSH Prohlížeč
• PLA2G4A protein, human MeSH Prohlížeč
• polynenasycené alkamidy MeSH
• receptor kanabinoidní CB1 MeSH

AIMS/HYPOTHESIS: Diets rich in n-3 polyunsaturated fatty acids, namely eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), protect against insulin resistance and obesity in rodents and increase insulin sensitivity in healthy humans. We tested whether the anti-diabetic effects of EPA and DHA involve enhanced production of the endogenous insulin sensitiser, adiponectin. METHODS: We studied the effects, in an obesity-promoting high-fat diet, of partial replacement of vegetable oils by EPA/DHA concentrate (6% EPA, 51% DHA) over a 5-week period in adult male C57BL/6J mice that either had free access to food or had their food intake restricted by 30%. At the end of the treatment, systemic markers of lipid and glucose metabolism and full-length adiponectin and leptin were measured. Adiponectin (Adipoq) and leptin (Lep) gene expression in dorsolumbar and epididymal white adipose tissue (WAT) and isolated adipocytes was quantified and adipokine production from WAT explants evaluated. RESULTS: In mice with free access to food, plasma triacylglycerols, NEFA, and insulin levels were lower in the presence of EPA/DHA, while glucose and leptin levels were not significantly altered. Food restriction decreased plasma triacylglycerols, glucose, insulin and leptin, but not adiponectin. EPA/DHA increased plasma adiponectin levels, independent of food intake, reflecting the stimulation of Adipoq expression in adipocytes and the release of adiponectin from WAT, particularly from epididymal fat. Expression of Lep and the release of leptin from WAT, while being extremely sensitive to caloric restriction, was unaltered by EPA/DHA. CONCLUSIONS/INTERPRETATION: Intake of diets rich in EPA and DHA leads to elevated systemic concentrations of adiponectin, largely independent of food intake or adiposity and explain, to some extent, their anti-diabetic effects.

• MeSH
• adiponektin biosyntéza   krev   genetika   MeSH
• aktivace enzymů MeSH
• dietní tuky aplikace a dávkování   farmakologie   MeSH
• glukosa metabolismus   MeSH
• inzulin krev   fyziologie   MeSH
• inzulinová rezistence MeSH
• kalorická restrikce MeSH
• kinasy AMP aktivovaných proteinkinas MeSH
• kyselina eikosapentaenová aplikace a dávkování   farmakologie   MeSH
• kyseliny dokosahexaenové aplikace a dávkování   farmakologie   MeSH
• leptin analýza   krev   genetika   fyziologie   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• obezita patofyziologie   prevence a kontrola   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• přijímání potravy MeSH
• proteinkinasy metabolismus   MeSH
• regulace genové exprese MeSH
• složení těla MeSH
• triglyceridy krev   MeSH
• tuková tkáň chemie   metabolismus   MeSH
• tukové buňky chemie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adiponektin MeSH
• dietní tuky MeSH
• glukosa MeSH
• inzulin MeSH
• kinasy AMP aktivovaných proteinkinas MeSH
• kyselina eikosapentaenová MeSH
• kyseliny dokosahexaenové MeSH
• leptin MeSH
• proteinkinasy MeSH
• triglyceridy MeSH