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《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2019,1864(3):271-280
Caffeine intake is associated with a reduced risk developing non-alcoholic fatty liver disease (NAFLD), but the underlying molecular mechanisms remain to be fully elucidated. We report here that caffeine markedly improved high fat diet-induced NAFLD in mice resulting in a 10-fold increase in circulating IL-6 levels, leading to STAT3 activation in the liver. Interestingly, the expression of IL-6 mRNA was not increased in the liver, but increased substantially in the muscles of caffeine-treated mice. Caffeine was found to stimulate IL-6 production in cultured myotubes but not in hepatocytes, adipocytes, or macrophages. The inhibition of p38/MAPK abrogated caffeine-induced IL-6 production in muscle cells. Caffeine failed to improve NAFLD in IL-6 and hepatocyte-specific STAT3 knockout mice, indicating that the IL-6/STAT3 pathway is vital for the hepatoprotective effects of caffeine in NAFLD. The possibility that IL-6/STAT3-mediated hepatic autophagosome induction and hepatocytic oxygen consumption are involved in the anti-NAFLD effects of caffeine cannot be excluded, based on the findings presented here. Our results reveal that caffeine ameliorates NAFLD via crosstalk between muscle IL-6 production and liver STAT3 activation. 相似文献
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Seven previously undescribed metabolites, designated as tricycloalternarenes Q–W (1–7), were isolated and identified from the fermented rice substrate of fungus Alternaria brassicicola. The planar and absolute structures of all new compounds were determined on the basis of extensive NMR spectroscopic data, a modified Mosher’s method, X-ray crystallographic analysis, and electronic circular dichroism (ECD) spectral analyses. All the isolates were evaluated for in vitro cytotoxicity against five human tumor MM231, MM468, HeLa, SW1990, and SW480 cell lines, and compounds 1, 2, 5, and 7 showed selective cytotoxicity against certain human tumor cell lines with IC50 values ranging from 12.83 to 32.87 μM, with no obvious cytotoxicity to the normal LO2 cell. 相似文献
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正Dear Editor,The fall armyworm, Spodoptera frugiperda(Lepidoptera:Noctuidae), a highly agricultural destructive pest of cereals, is originally rampant in tropical and subtropical America(Kenis et al. 2019). The caterpillars of this moth feed on more than 350 plant species(Harrison et al. 2019), 相似文献
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Three new drimane-type sesquiterpenoids named xylariaines A–C (1–3), together with one known analogue (4), were isolated from the ethyl acetate extract of cultures of the fungus Xylaria polymorpha (Pers.: Fr.) Grer. Their structures were elucidated unambiguously by NMR and single-crystal X-ray diffraction analysis. Compounds 1 and 2 exhibited weak anti-acetylcholinesterase activities at a concentration of 50 μg/mL with inhibition ratios of 12.4% and 18.0%, respectively. 相似文献
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《Bioorganic & medicinal chemistry letters》2014,24(24):5679-5682
To discover new natural-product-based insecticidal agents, a series of novel oxime derivatives of podophyllotoxin-based phenazines modified in the C, D and E rings of podophyllotoxin were prepared and tested as insecticidal agents against the pre-third-instar larvae of oriental armyworm, Mythimna separata (Walker) in vivo at 1 mg/mL. The steric configuration of IIIc was unambiguously confirmed by single-crystal X-ray diffraction analysis. Compounds IIIa–d, and IIIi exhibited an equal or higher insecticidal activity than toosendanin. 相似文献
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