Intrahepatic fat deposition has been demonstrated in patients with nonalcoholic fatty liver disease(NAFLD). Genetic and environmental factors are important for the development of NAFLD. Diseases such as obesity, diabe...Intrahepatic fat deposition has been demonstrated in patients with nonalcoholic fatty liver disease(NAFLD). Genetic and environmental factors are important for the development of NAFLD. Diseases such as obesity, diabetes, and hypertension have been found to be closely associated with the incidence of NAFLD. Evi-dence suggests that obesity and insulin resistance are the major factors that contribute to the development of NAFLD. In comparing the factors that contribute to the buildup of excess calories in obesity, an imbalance of energy homeostasis can be considered as the basis. Among the peripheral signals that are generated to regulate the uptake of food, signals from adipose tissue are of major relevance and involve the maintenance of energy homeostasis through processes such as lipo-genesis, lipolysis, and oxidation of fatty acids. Advances in research on adipose tissue suggest an integral role played by adipokines in NAFLD. Cytokines secreted by adipocytes, such as tumor necrosis factor-α, transform-ing growth factor-β, and interleukin-6, are implicated in NAFLD. Other adipokines, such as leptin and adiponectin and, to a lesser extent, resistin and retinol binding protein-4 are also involved. Leptin and adiponectin can augment the oxidation of fatty acid in liver by activating the nuclear receptor super-family of transcription fac-tors, namely peroxisome proliferator-activated receptor(PPAR)-α. Recent studies have proposed downregula-tion of PPAR-α in cases of hepatic steatosis. This re-view discusses the role of adipokines and PPARs with regard to hepatic energy metabolism and progression of NAFLD.展开更多
Adipose tissue is not an inert cell mass contributing only to the storage of fat, but a sophisticated ensemble of cellular components with highly specialized and complex functions. In addition to managing the most imp...Adipose tissue is not an inert cell mass contributing only to the storage of fat, but a sophisticated ensemble of cellular components with highly specialized and complex functions. In addition to managing the most important energy reserve of the body, it secretes a multitude of soluble proteins called adipokines, which have beneficial or, alternatively, deleterious effects on the homeostasis of the whole body. The expression of these adipokines is an integrated response to various signals received from many organs, which depends heavily on the integrity and physiological status of the adipose tissue. One of the main regulators of gene expression in fat is the transcription factor peroxisome proliferatoractivated receptor γ （PPARγ）, which is a fatty acid- and eicosanoid-dependent nuclear receptor that plays key roles in the development and maintenance of the adipose tissue. Furthermore, synthetic PPAR7 agonists are therapeutic agents used in the treatment of type 2 diabetes. This review discusses recent knowledge on the link between fat physiology and metabolic diseases, and the roles of PPARγ in this interplay via the regulation of lipid and glucose metabolism. Finally, we assess the putative benefits of targeting this nuclear receptor with still-to-be-identified highly selective PPARγ modulators.展开更多
This experiment was conducted to investigate the effects of branched-chain amino acids(BCAA)supplemented in protein-restricted diets on the growth performance and the expression profile of amino acid transporters and ...This experiment was conducted to investigate the effects of branched-chain amino acids(BCAA)supplemented in protein-restricted diets on the growth performance and the expression profile of amino acid transporters and energy metabolism related regulators in the white adipose tissue(WAT)of different regional depots including dorsal subcutaneous adipose(DSA) and abdominal subcutaneous adipose(ASA), A total of 24 crossbred barrows(7.40 ± 0.70 kg) were randomly divided into 4 groups and were fed the following isocaloric diets for 33 days: 1) a recommended adequate protein diet(AP, 20% CP, as a positive control); 2) a low protein diet(LP, 17% CP); 3) the LP diet supplemented with BCAA(LP + B, 17% CP) to reach the same level of the AP diet group; 4) the LP diet supplemented with 2 times the amount of BCAA(LP + 2B, 17% CP). The daily gain and daily feed intake of the LP diet group were the lowest among all the treatments(P < 0.01). The feed conversion was improved markedly in the group of LP + B compared with the LP diet group(P < 0.05). No significant difference was noted for the serum biochemical parameter concentrations of glucose, triglyceride, nonesterified fatty acid and insulin among the groups(P > 0.05). Moreover, BCAA supplementation down-regulated the expression levels of amino acid transporters including L-type amino acid transporter 1 and sodium-coupled neutral amino acid transporter 2 in DSA, but up-regulated the expression level of Ltype amino acid transporter 4 in ASA(P < 0.05), Meanwhile, the energy sensor AMP-activated protein kinase α was activated in the DSA of pigs fed LP diet and in the ASA of the pigs fed AP or LP + 2B diets(P < 0.05). The mRNA expression profile of the selected mitochondrial component and mitochondrial biogenesis associated regulators in DSA and ASA also responded differently to dietary BCAA supplementation. These results suggested that the growth performance of growing pigs fed protein restricted diets supplemented with BCAA could catch up to that of the pigs fed AP diets. The r展开更多
AIM: To investigate the metabolic changes in skeletal muscle and/or adipose tissue in glucagon-like peptide-1-induced improvement of nonalcoholic fatty liver disease (NAFLD).
Electrospinning is a simple and versatile technique that uses electrostatic forces to create fbers in the nano o micro range from a variety of materials,both synthetic and natural Due to the high surface area to volum...Electrospinning is a simple and versatile technique that uses electrostatic forces to create fbers in the nano o micro range from a variety of materials,both synthetic and natural Due to the high surface area to volume ratio,high porosity,and desirable mechanic characteristics of electrospun fbers,they are of current interest for a wide variety of applications.Some of the most signifcant applications of these fbers being researched include tissue engineering.drug delivery,wound dressings,environmental and energy applications,and protective materials.Notably,electrospun fbers may be specially tailored to better ft their fnal application through the direct 1oading of materials during the spining process as well as by choosing the correct base material for the fber.For example,it is desirable to use a biocompatible and biodegradable material in fibers desired for applications in the biomedical field;this way the fbers are able to safely interact with the human body.This review will explore the applications,as previously listed,with a focus on how fbers are made using carbohydrate polymers(such as alginate,cellulose and its derivatives,chitosan and chitin,starch,pul1ulan,hyaluronic acid,dextran,and 1evan)as their base material,and their applicability and functionality in various applications.展开更多
文摘Intrahepatic fat deposition has been demonstrated in patients with nonalcoholic fatty liver disease(NAFLD). Genetic and environmental factors are important for the development of NAFLD. Diseases such as obesity, diabetes, and hypertension have been found to be closely associated with the incidence of NAFLD. Evi-dence suggests that obesity and insulin resistance are the major factors that contribute to the development of NAFLD. In comparing the factors that contribute to the buildup of excess calories in obesity, an imbalance of energy homeostasis can be considered as the basis. Among the peripheral signals that are generated to regulate the uptake of food, signals from adipose tissue are of major relevance and involve the maintenance of energy homeostasis through processes such as lipo-genesis, lipolysis, and oxidation of fatty acids. Advances in research on adipose tissue suggest an integral role played by adipokines in NAFLD. Cytokines secreted by adipocytes, such as tumor necrosis factor-α, transform-ing growth factor-β, and interleukin-6, are implicated in NAFLD. Other adipokines, such as leptin and adiponectin and, to a lesser extent, resistin and retinol binding protein-4 are also involved. Leptin and adiponectin can augment the oxidation of fatty acid in liver by activating the nuclear receptor super-family of transcription fac-tors, namely peroxisome proliferator-activated receptor(PPAR)-α. Recent studies have proposed downregula-tion of PPAR-α in cases of hepatic steatosis. This re-view discusses the role of adipokines and PPARs with regard to hepatic energy metabolism and progression of NAFLD.
基金supported by the Etat de Vaud and the Swiss National Science Foundation.
文摘Adipose tissue is not an inert cell mass contributing only to the storage of fat, but a sophisticated ensemble of cellular components with highly specialized and complex functions. In addition to managing the most important energy reserve of the body, it secretes a multitude of soluble proteins called adipokines, which have beneficial or, alternatively, deleterious effects on the homeostasis of the whole body. The expression of these adipokines is an integrated response to various signals received from many organs, which depends heavily on the integrity and physiological status of the adipose tissue. One of the main regulators of gene expression in fat is the transcription factor peroxisome proliferatoractivated receptor γ （PPARγ）, which is a fatty acid- and eicosanoid-dependent nuclear receptor that plays key roles in the development and maintenance of the adipose tissue. Furthermore, synthetic PPAR7 agonists are therapeutic agents used in the treatment of type 2 diabetes. This review discusses recent knowledge on the link between fat physiology and metabolic diseases, and the roles of PPARγ in this interplay via the regulation of lipid and glucose metabolism. Finally, we assess the putative benefits of targeting this nuclear receptor with still-to-be-identified highly selective PPARγ modulators.
基金supported by National Basic Research Program of China (2013CB127305, 2012CB124704)National Nature Science Foundation of China (31110103909, 31330075)+3 种基金Nature Science Foundation of Hunan (2015JJ2146)The Chinese Academy of Sciences STS Project(KFJ-EW-STS-063)Key Projects in the National Science & Technology Pillar Program (2013BAD21B04)Hunan Province project (2014GK1007)
文摘This experiment was conducted to investigate the effects of branched-chain amino acids(BCAA)supplemented in protein-restricted diets on the growth performance and the expression profile of amino acid transporters and energy metabolism related regulators in the white adipose tissue(WAT)of different regional depots including dorsal subcutaneous adipose(DSA) and abdominal subcutaneous adipose(ASA), A total of 24 crossbred barrows(7.40 ± 0.70 kg) were randomly divided into 4 groups and were fed the following isocaloric diets for 33 days: 1) a recommended adequate protein diet(AP, 20% CP, as a positive control); 2) a low protein diet(LP, 17% CP); 3) the LP diet supplemented with BCAA(LP + B, 17% CP) to reach the same level of the AP diet group; 4) the LP diet supplemented with 2 times the amount of BCAA(LP + 2B, 17% CP). The daily gain and daily feed intake of the LP diet group were the lowest among all the treatments(P < 0.01). The feed conversion was improved markedly in the group of LP + B compared with the LP diet group(P < 0.05). No significant difference was noted for the serum biochemical parameter concentrations of glucose, triglyceride, nonesterified fatty acid and insulin among the groups(P > 0.05). Moreover, BCAA supplementation down-regulated the expression levels of amino acid transporters including L-type amino acid transporter 1 and sodium-coupled neutral amino acid transporter 2 in DSA, but up-regulated the expression level of Ltype amino acid transporter 4 in ASA(P < 0.05), Meanwhile, the energy sensor AMP-activated protein kinase α was activated in the DSA of pigs fed LP diet and in the ASA of the pigs fed AP or LP + 2B diets(P < 0.05). The mRNA expression profile of the selected mitochondrial component and mitochondrial biogenesis associated regulators in DSA and ASA also responded differently to dietary BCAA supplementation. These results suggested that the growth performance of growing pigs fed protein restricted diets supplemented with BCAA could catch up to that of the pigs fed AP diets. The r
文摘AIM: To investigate the metabolic changes in skeletal muscle and/or adipose tissue in glucagon-like peptide-1-induced improvement of nonalcoholic fatty liver disease (NAFLD).
文摘Electrospinning is a simple and versatile technique that uses electrostatic forces to create fbers in the nano o micro range from a variety of materials,both synthetic and natural Due to the high surface area to volume ratio,high porosity,and desirable mechanic characteristics of electrospun fbers,they are of current interest for a wide variety of applications.Some of the most signifcant applications of these fbers being researched include tissue engineering.drug delivery,wound dressings,environmental and energy applications,and protective materials.Notably,electrospun fbers may be specially tailored to better ft their fnal application through the direct 1oading of materials during the spining process as well as by choosing the correct base material for the fber.For example,it is desirable to use a biocompatible and biodegradable material in fibers desired for applications in the biomedical field;this way the fbers are able to safely interact with the human body.This review will explore the applications,as previously listed,with a focus on how fbers are made using carbohydrate polymers(such as alginate,cellulose and its derivatives,chitosan and chitin,starch,pul1ulan,hyaluronic acid,dextran,and 1evan)as their base material,and their applicability and functionality in various applications.
