Metabolic dysfunction-associated steatotic liver disease (MASLD) occurs in subjects with obesity and metabolic syndrome. MASLD may progress from simple steatosis (i.e., hepatic steatosis) to steatohepatitis, characterized by inflammatory changes and liver cell damage, substantially increasing mortality. Lifestyle measures associated with weight loss and/or appropriate diet help reduce liver fat accumulation, thereby potentially limiting progression to steatohepatitis. As for diet, both total energy and macronutrient composition significantly influence the liver's fat content. For example, the type of dietary fatty acids can affect the metabolism of lipids and hence their tissue accumulation, with saturated fatty acids having a greater ability to promote fat storage in the liver than polyunsaturated ones. In particular, polyunsaturated fatty acids of n-3 series (omega-3), such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), have been intensively studied for their antisteatotic effects, both in preclinical animal models of obesity and hepatic steatosis and in overweight/obese patients. Their effects may depend not only on the dose and duration of administration of omega-3, or DHA/EPA ratio, but also on the lipid class used for their supplementation. This review summarizes the available evidence from recent comparative studies using omega-3 supplementation via different lipid classes. Albeit the evidence is mainly limited to preclinical studies, it suggests that phospholipids and possibly wax esters could provide greater efficacy against MASLD compared to traditional chemical forms of omega-3 supplementation (i.e., triacylglycerols, ethyl esters). This cannot be attributed solely to improved EPA and/or DHA bioavailability, but other mechanisms may be involved. Keywords: MASLD • Metabolic dysfunction-associated steatotic liver disease • NAFLD • Non-alcoholic fatty liver disease • n-3 polyunsaturated fatty acids.

• MeSH
• játra * metabolismus   účinky léků   patologie   MeSH
• lidé MeSH
• metabolismus lipidů účinky léků   MeSH
• nealkoholová steatóza jater metabolismus   farmakoterapie   dietoterapie   patologie   MeSH
• obezita metabolismus   farmakoterapie   dietoterapie   patologie   MeSH
• omega-3 mastné kyseliny * aplikace a dávkování   metabolismus   terapeutické užití   MeSH
• potravní doplňky * MeSH
• ztučnělá játra metabolismus   farmakoterapie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• omega-3 mastné kyseliny * MeSH

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

Preclinical evidence suggests that n-3 fatty acids EPA and DHA (Omega-3) supplemented as phospholipids (PLs) may be more effective than triacylglycerols (TAGs) in reducing hepatic steatosis. To further test the ability of Omega-3 PLs to alleviate liver steatosis, we used a model of exacerbated non-alcoholic fatty liver disease based on high-fat feeding at thermoneutral temperature. Male C57BL/6N mice were fed for 24 weeks a lard-based diet given either alone (LHF) or supplemented with Omega-3 (30 mg/g diet) as PLs (krill oil; ω3PL) or TAGs (Epax 3000TG concentrate; ω3TG), which had a similar total content of EPA and DHA and their ratio. Substantial levels of TAG accumulation (~250 mg/g) but relatively low inflammation/fibrosis levels were achieved in the livers of control LHF mice. Liver steatosis was reduced by >40% in the ω3PL but not ω3TG group, and plasma ALT levels were markedly reduced (by 68%) in ω3PL mice as well. Krill oil administration also improved hepatic insulin sensitivity, and its effects were associated with high plasma adiponectin levels (150% of LHF mice) along with superior bioavailability of EPA, increased content of alkaloids stachydrine and trigonelline, suppression of lipogenic gene expression, and decreased diacylglycerol levels in the liver. This study reveals that in addition to Omega-3 PLs, other constituents of krill oil, such as alkaloids, may contribute to its strong antisteatotic effects in the liver.

• Klíčová slova
• C57BL/6N mice, NAFLD, high-fat diet, krill oil, obesity, omega-3, phospholipids, thermoneutral temperature,
• MeSH
• bydlení zvířat MeSH
• dieta s vysokým obsahem tuků škodlivé účinky   MeSH
• Euphausiacea MeSH
• fosfolipidy farmakologie   MeSH
• fyziologie výživy zvířat MeSH
• inzulinová rezistence MeSH
• játra metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nealkoholová steatóza jater etiologie   terapie   MeSH
• obezita etiologie   terapie   MeSH
• potravní doplňky * MeSH
• rybí oleje farmakologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfolipidy MeSH
• rybí oleje MeSH

Antisteatotic effects of omega-3 fatty acids (Omega-3) in obese rodents seem to vary depending on the lipid form of their administration. Whether these effects could reflect changes in intestinal metabolism is unknown. Here, we compare Omega-3-containing phospholipids (krill oil; ω3PL-H) and triacylglycerols (ω3TG) in terms of their effects on morphology, gene expression and fatty acid (FA) oxidation in the small intestine. Male C57BL/6N mice were fed for 8 weeks with a high-fat diet (HFD) alone or supplemented with 30 mg/g diet of ω3TG or ω3PL-H. Omega-3 index, reflecting the bioavailability of Omega-3, reached 12.5% and 7.5% in the ω3PL-H and ω3TG groups, respectively. Compared to HFD mice, ω3PL-H but not ω3TG animals had lower body weight gain (-40%), mesenteric adipose tissue (-43%), and hepatic lipid content (-64%). The highest number and expression level of regulated intestinal genes was observed in ω3PL-H mice. The expression of FA ω-oxidation genes was enhanced in both Omega-3-supplemented groups, but gene expression within the FA β-oxidation pathway and functional palmitate oxidation in the proximal ileum was significantly increased only in ω3PL-H mice. In conclusion, enhanced intestinal FA oxidation could contribute to the strong antisteatotic effects of Omega-3 when administered as phospholipids to dietary obese mice.

• Klíčová slova
• Omega-3 index, Omega-3 phospholipids, high-fat diet, krill oil, small intestine,
• MeSH
• dieta s vysokým obsahem tuků * MeSH
• erytrocytární membrána metabolismus   MeSH
• Euphausiacea MeSH
• fosfolipidy aplikace a dávkování   MeSH
• krevní glukóza analýza   MeSH
• mastné kyseliny metabolismus   MeSH
• metabolismus lipidů účinky léků   MeSH
• myši obézní MeSH
• oleje MeSH
• omega-3 mastné kyseliny aplikace a dávkování   MeSH
• oxidace-redukce MeSH
• střeva anatomie a histologie   MeSH
• střevní sliznice metabolismus   MeSH
• tělesná hmotnost MeSH
• triglyceridy aplikace a dávkování   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfolipidy MeSH
• krevní glukóza MeSH
• mastné kyseliny MeSH
• oleje MeSH
• omega-3 mastné kyseliny MeSH
• triglyceridy MeSH