Glucose is used aerobically and anaerobically to generate energy for cells.Glucose transporters(GLUTs)are transmembrane proteins that transport glucose across the cell membrane.Insulin promotes glucose utilization in ...Glucose is used aerobically and anaerobically to generate energy for cells.Glucose transporters(GLUTs)are transmembrane proteins that transport glucose across the cell membrane.Insulin promotes glucose utilization in part through promoting glucose entry into the skeletal and adipose tissues.This has been thought to be achieved through insulin-induced GLUT4 translocation from intracellular compartments to the cell membrane,which increases the overall rate of glucose flux into a cell.The insulin-induced GLUT4 translocation has been investigated extensively.Recently,significant progress has been made in our understanding of GLUT4 expression and translocation.Here,we summarized the methods and reagents used to determine the expression levels of Slc2a4 mRNA and GLUT4 protein,and GLUT4 translocation in the skeletal muscle,adipose tissues,heart and brain.Overall,a variety of methods such real-time polymerase chain reaction,immunohistochemistry,fluorescence microscopy,fusion proteins,stable cell line and transgenic animals have been used to answer particular questions related to GLUT4 system and insulin action.It seems that insulininduced GLUT4 translocation can be observed in the heart and brain in addition to the skeletal muscle and adipocytes.Hormones other than insulin can induce GLUT4 translocation.Clearly,more studies of GLUT4 are warranted in the future to advance of our understanding of glucose homeostasis.展开更多
Hypercholesterolemia is a risk factor of cardiovascular diseases,which have been managed using statin drugs.Red yeast rice(RYR)as a traditional food in the Eastern Asia countries has anti-hyperlipidemia activity.Recen...Hypercholesterolemia is a risk factor of cardiovascular diseases,which have been managed using statin drugs.Red yeast rice(RYR)as a traditional food in the Eastern Asia countries has anti-hyperlipidemia activity.Recently,a variety of food supplement products containing RYR have been developed to lower blood cholesterol,which is attributed to the presence of monacolins,especially monacolin K(lovastatin,a statin drug).This review was aimed to summarize the clinical trials using RYR products to investigate their effects on lipid profiles in humans.Relevant articles of human clinical trials were retrieved from PubMed and discussed here.Results showed that RYR and its extracts have been included in commercially available products alone and in combinations with various other materials,which include bioactive compounds such as coenzyme Q10 and berberine,vitamins,extracts from other plants such as phytosterols,polyunsaturated fatty acids or even probiotics.The durations of the trials ranged from 4 weeks to 60 months.The content of monacolin K ranged from 0.32 mg/pack to 10 mg/pack.The data of these human clinical trials demonstrated that these RYR supplement products were sufficient to reduce blood cholesterol in different populations.However,the inclusions of certain materials might not have additive effect.Additionally,studies including a lovastatin only positive control group with the equivalent dose as that of monacolin K in the RYR products remain to be done.Furthermore,variations of monacolin K contents and presence of toxic citrinin are still concerns.Last,bioactivities of other components in RYR should be investigated as well.More future studies will certainly help to fully explore the potentials of this traditional food in the combat against cardiovascular and other metabolic diseases.展开更多
基金We would like to thank the Department of Nutrition at the University of Tennessee at Knoxville for financial support to T.W.G.C.would like to thank Yantai Zestern Biotechnique Co.LTD for the research funding support.
文摘Glucose is used aerobically and anaerobically to generate energy for cells.Glucose transporters(GLUTs)are transmembrane proteins that transport glucose across the cell membrane.Insulin promotes glucose utilization in part through promoting glucose entry into the skeletal and adipose tissues.This has been thought to be achieved through insulin-induced GLUT4 translocation from intracellular compartments to the cell membrane,which increases the overall rate of glucose flux into a cell.The insulin-induced GLUT4 translocation has been investigated extensively.Recently,significant progress has been made in our understanding of GLUT4 expression and translocation.Here,we summarized the methods and reagents used to determine the expression levels of Slc2a4 mRNA and GLUT4 protein,and GLUT4 translocation in the skeletal muscle,adipose tissues,heart and brain.Overall,a variety of methods such real-time polymerase chain reaction,immunohistochemistry,fluorescence microscopy,fusion proteins,stable cell line and transgenic animals have been used to answer particular questions related to GLUT4 system and insulin action.It seems that insulininduced GLUT4 translocation can be observed in the heart and brain in addition to the skeletal muscle and adipocytes.Hormones other than insulin can induce GLUT4 translocation.Clearly,more studies of GLUT4 are warranted in the future to advance of our understanding of glucose homeostasis.
基金the Diabetes Action Research and Education Foundation for the research grant(#466)to G.Chen.
文摘Hypercholesterolemia is a risk factor of cardiovascular diseases,which have been managed using statin drugs.Red yeast rice(RYR)as a traditional food in the Eastern Asia countries has anti-hyperlipidemia activity.Recently,a variety of food supplement products containing RYR have been developed to lower blood cholesterol,which is attributed to the presence of monacolins,especially monacolin K(lovastatin,a statin drug).This review was aimed to summarize the clinical trials using RYR products to investigate their effects on lipid profiles in humans.Relevant articles of human clinical trials were retrieved from PubMed and discussed here.Results showed that RYR and its extracts have been included in commercially available products alone and in combinations with various other materials,which include bioactive compounds such as coenzyme Q10 and berberine,vitamins,extracts from other plants such as phytosterols,polyunsaturated fatty acids or even probiotics.The durations of the trials ranged from 4 weeks to 60 months.The content of monacolin K ranged from 0.32 mg/pack to 10 mg/pack.The data of these human clinical trials demonstrated that these RYR supplement products were sufficient to reduce blood cholesterol in different populations.However,the inclusions of certain materials might not have additive effect.Additionally,studies including a lovastatin only positive control group with the equivalent dose as that of monacolin K in the RYR products remain to be done.Furthermore,variations of monacolin K contents and presence of toxic citrinin are still concerns.Last,bioactivities of other components in RYR should be investigated as well.More future studies will certainly help to fully explore the potentials of this traditional food in the combat against cardiovascular and other metabolic diseases.