Fish oil (mainly omega 3 polyunsaturated fatty acids), differently from lard (mainly saturated fatty acids) has been suggested to have anti-inflammatory effects associated with amelioration of insulin sensibility. An ...Fish oil (mainly omega 3 polyunsaturated fatty acids), differently from lard (mainly saturated fatty acids) has been suggested to have anti-inflammatory effects associated with amelioration of insulin sensibility. An important role in skeletal muscle insulin resistance development has been recently attributed to mitochondrial dynamic behavior. Mitochondria are dynamic organelles that frequently undergo fission/fusion processes and a shift toward fission process has been associated with skeletal muscle mitochondrial dysfunction and insulin resistance development. The present work aimed to evaluate if the replacement of lard with fish oil in high-fat diet positively affect skeletal muscle mitochondrial dynamic behavior in association with the improvement of insulin-resistance. Body weight gain, systemic insulin-resistance (glucose/insulin ratio), serum TNFα levels and skeletal muscle lipid content were assessed in rats fed a high-lard or high-fish-oil diet for 6 weeks. In skeletal muscle sections, immunohistochemical analysis were performed to detect the presence of insulin receptor substrate 1 (IRS1) and tyrosine phosphorylated IRS1 (key factor in insulin signalling pathway) as well as to detect the main proteins involved in mitochondrial fusion (MFN2 and OPA1) and fission (DRP1 and Fis1) processes. Skeletal muscle mitochondrial ultrastructural features were assessed by electron microscopy. High-fish oil feeding induced lower body weight gain, systemic inflammation and insulin-resistance development as well as skeletal muscle lipid accumulation compared to high-lard feeding. Skeletal muscle sections from high-fish oil fed rats exhibited a greater number of immunoreactive fibers for MFN2 and OPA1 proteins as well as weaker immunostaining for DRP1 and Fis1 compared to sections from high-lard fed rats. Electron microscopy observations suggested a prominent presence of fission events in L rats and fusion events in F rats. The positive effect of the replacement of lard with fish oil in high-fat diet on systemic and skeletal muscle insulin sensibility was associated to changes in mitochondrial dynamic behavior.展开更多
The isolation of microorganisms for biodegradation of minimal fats and oils at low temperatures was reported. By using rapeseed oil as a sole carbon source, six strains were isolated from five kinds of oils/fats-conta...The isolation of microorganisms for biodegradation of minimal fats and oils at low temperatures was reported. By using rapeseed oil as a sole carbon source, six strains were isolated from five kinds of oils/fats-contaminated wastewater, soil, and active sludge. Among them, two strains which show the highest oil removal ratios were identified as Pseudomonas pseudoalcaligenes and Pseudomonas mendocina, respectively. The experiments of orthogonal impact conditions show that the optimal oil degradation condition is at pH 8.0, 5 ℃ and 100 mg/L oil. Under this condition, the rapeseed oil degradation ratios of two strains after 24 hours amount to 92.6% and 92.0% respectively, whereas the removal ratios of lard decrease to 39.5% and 54.3%.展开更多
文摘Fish oil (mainly omega 3 polyunsaturated fatty acids), differently from lard (mainly saturated fatty acids) has been suggested to have anti-inflammatory effects associated with amelioration of insulin sensibility. An important role in skeletal muscle insulin resistance development has been recently attributed to mitochondrial dynamic behavior. Mitochondria are dynamic organelles that frequently undergo fission/fusion processes and a shift toward fission process has been associated with skeletal muscle mitochondrial dysfunction and insulin resistance development. The present work aimed to evaluate if the replacement of lard with fish oil in high-fat diet positively affect skeletal muscle mitochondrial dynamic behavior in association with the improvement of insulin-resistance. Body weight gain, systemic insulin-resistance (glucose/insulin ratio), serum TNFα levels and skeletal muscle lipid content were assessed in rats fed a high-lard or high-fish-oil diet for 6 weeks. In skeletal muscle sections, immunohistochemical analysis were performed to detect the presence of insulin receptor substrate 1 (IRS1) and tyrosine phosphorylated IRS1 (key factor in insulin signalling pathway) as well as to detect the main proteins involved in mitochondrial fusion (MFN2 and OPA1) and fission (DRP1 and Fis1) processes. Skeletal muscle mitochondrial ultrastructural features were assessed by electron microscopy. High-fish oil feeding induced lower body weight gain, systemic inflammation and insulin-resistance development as well as skeletal muscle lipid accumulation compared to high-lard feeding. Skeletal muscle sections from high-fish oil fed rats exhibited a greater number of immunoreactive fibers for MFN2 and OPA1 proteins as well as weaker immunostaining for DRP1 and Fis1 compared to sections from high-lard fed rats. Electron microscopy observations suggested a prominent presence of fission events in L rats and fusion events in F rats. The positive effect of the replacement of lard with fish oil in high-fat diet on systemic and skeletal muscle insulin sensibility was associated to changes in mitochondrial dynamic behavior.
文摘The isolation of microorganisms for biodegradation of minimal fats and oils at low temperatures was reported. By using rapeseed oil as a sole carbon source, six strains were isolated from five kinds of oils/fats-contaminated wastewater, soil, and active sludge. Among them, two strains which show the highest oil removal ratios were identified as Pseudomonas pseudoalcaligenes and Pseudomonas mendocina, respectively. The experiments of orthogonal impact conditions show that the optimal oil degradation condition is at pH 8.0, 5 ℃ and 100 mg/L oil. Under this condition, the rapeseed oil degradation ratios of two strains after 24 hours amount to 92.6% and 92.0% respectively, whereas the removal ratios of lard decrease to 39.5% and 54.3%.