Energy metabolism is significantly reprogrammed in many human cancers, and these alterations confer many advantages to cancer cells, including the pro- motion of biosynthesis, ATP generation, detoxification and suppor...Energy metabolism is significantly reprogrammed in many human cancers, and these alterations confer many advantages to cancer cells, including the pro- motion of biosynthesis, ATP generation, detoxification and support of rapid proliferation. The pentose phos- phate pathway （PPP） is a major pathway for glucose catabolism. The PPP directs glucose flux to its oxi- dative branch and produces a reduced form of nico- tinamide adenine dinucleotide phosphate （NADPH）, an essential reductant in anabolic processes. It has become clear that the PPP plays a critical role in regulating cancer cell growth by supplying cells with not only ribose-5-phosphate but also NADPH for detoxification of intracellular reactive oxygen species, reductive biosynthesis and ribose biogenesis. Thus, alteration of the PPP contributes directly to cell pro- liferation, survival and senescence. Furthermore, recent studies have shown that the PPP is regulated oncogenically and/or metabolically by numerous fac- tors, including tumor suppressors, oncoproteins and intracellular metabolites. Dysregulation of PPP flux dramatically impacts cancer growth and survival. Therefore, a better understanding of how the PPP is reprogrammed and the mechanism underlying the balance between glycolysis and PPP flux in cancer will be valuable in developing therapeutic strategies targeting this pathway.展开更多
Helicobacter pylori(H.pylori)is still the most prevalent infection of the world.Colonization of the stomach by this agent will invariably induce chronic gastritis which is a low-grade inflammatory state leading to loc...Helicobacter pylori(H.pylori)is still the most prevalent infection of the world.Colonization of the stomach by this agent will invariably induce chronic gastritis which is a low-grade inflammatory state leading to local complications(peptic ulcer,gastric cancer,lymphoma)and remote manifestations.While H.pylori does not enter circulation,these extragastric manifestations are probably mediated by the cytokines and acute phase proteins produced by the inflammed mucosa.The epidemiologic link between the H.pylori infection and metabolic changes is inconstant and controversial.Growth delay was described mainly in low-income regions with high prevalence of the infection,where probably other nutritional and social factors contribute to it.The timely eradication of the infection will lead to a more healthy development of the young population,along with preventing peptic ulcers and gastric cancer An increase of total,low density lipoprotein and high density liporotein cholesterol levels in some infected people creates an atherogenic lipid profile which could promote atherosclerosis with its complications,myocardial infarction,stroke and peripheral vascular disease.Well designed and adequately powered long-term studies are required to see whether eradication of the infection will prevent these conditions.In case of glucose metabolism,the most consistent association was found between H.pylori and insulin resistance:again,proof that eradication prevents this common metabolic disturbance is expected.The results of eradication with standard regimens in diabetics are significantly worse than in non-diabetic patients,thus,more active regimens must be found to obtain better results.Successful eradication itself led to an increase of body mass index and cholesterol levels in some populations,while in others no such changes were encountered.Uncertainities of the metabolic consequences of H.pylori infection must be clarified in the future.展开更多
Glucose metabolism in gastric cancer cells differs from that of normal epithelial cells. Upregulated aerobic glycolysis(Warburg effect) in gastric cancer meeting the demands of cell proliferation is associated with ge...Glucose metabolism in gastric cancer cells differs from that of normal epithelial cells. Upregulated aerobic glycolysis(Warburg effect) in gastric cancer meeting the demands of cell proliferation is associated with genetic mutations, epigenetic modification and proteomic alteration. Understanding the mechanisms of aerobic glycolysis may contribute to our knowledge of gastric carcinogenesis. Metabolomic studies offer novel, convenient and practical tools in the search for new biomarkers for early detection, diagnosis, prognosis, and chemosensitivity prediction of gastric cancer. Interfering with the process of glycolysis in cancer cells may provide a new and promising therapeutic strategy for gastric cancer. In this article, we present a brief review of recent studies of glucose metabolism in gastric cancer, with primary focus on the clinical applications of new biomarkers and their potential therapeutic role in gastric cancer.展开更多
Contrary to the previous belief that insulin does not act in the brain, studies in the last three decades have demonstrated important roles of insulin and insulin signal transduction in various functions of the centra...Contrary to the previous belief that insulin does not act in the brain, studies in the last three decades have demonstrated important roles of insulin and insulin signal transduction in various functions of the central nervous system. Deregulated brain insulin signaling and its role in molecular pathogenesis have recently been reported in Alzheimer＇s disease （AD）. In this article, we review the roles of brain insulin signaling in memory and cognition, the metabolism of amyloid 13 precursor protein, and tau phosphorylation. We further discuss deficiencies of brain insulin signaling and glucose metabolism, their roles in the development of AD, and recent studies that target the brain insulin signaling pathway for the treatment of AD. It is clear now that deregulation of brain insulin signaling plays an important role in the development of sporadic AD. The brain insulin signaling pathway also offers a promising therapeutic target for treating AD and probably other neurodegenerative disorders.展开更多
Background Increasingly, evidence from population, clinic-based and laboratory studies supports an independent association between obstructive sleep apnea syndrome （OSAS） and an increased risk of type 2 diabetes; ho...Background Increasingly, evidence from population, clinic-based and laboratory studies supports an independent association between obstructive sleep apnea syndrome （OSAS） and an increased risk of type 2 diabetes; however, this observation has yet to be replicated in China and the potential mechanisms that link these two conditions are not clear. Methods A total of 179 Han Chinese subjects were enrolled in this study. All subjects underwent polysomnography, the oral glucose tolerance-insulin releasing test （OGTT-IRT） and serum HbAlc measurement. Indexes including homeostasis model assessment-IR （HOMA-IR）, Matsuda index, HOMA-β, early phase insulinogenic index （△I30 / △G30）, AUC-I180 and oral disposition index （DIo） were calculated for the assessment of insulin resistance and pancreatic β-cell function. Results Based on OGTT, 25.4%, 44.6% and 54.5% subjects were diagnosed having glucose metabolic disorders respectively in control, mild to moderate and severe OSAS groups （P 〈0.05）. Serum HbA1c levels were highest in subjects with severe OSAS （P 〈0.05）. In contrast, compared with normal subjects, HOMA-β, △I30/△G30 and DIo were lower in severe OSAS group （P 〈0.05）. In stepwise multiple linear regressions, 0-min glucose and HbAlc were positively correlated with the percentage of total sleep time below an oxyhemoglobin saturation of 90% （T90） （Beta = 0.215 and 0.368, P 〈0.05）; 30-min and 60-min glucose was negatively correlated with the lowest SpO2 （LSpO2） （Beta = -0.214 and -0.241, P 〈0.05）. HOMA-β and Dlowere negatively correlated with T90 （Beta = -0.153 and -0.169, P 〈0.05） while body mass index （BMI） was the only determinant of HOMA-IR and Matsuda index. Conclusions OSAS is associated with impairment in glucose tolerance and pancreatic β-cell function in Han Chinese subjects while insulin sensitivity is mainly determined by obesity.展开更多
Recent studies have revealed that bile acids(BAs)are not only facilitators of dietary lipid absorption but also important signaling molecules exerting multiple physiological functions.Some major signaling pathways inv...Recent studies have revealed that bile acids(BAs)are not only facilitators of dietary lipid absorption but also important signaling molecules exerting multiple physiological functions.Some major signaling pathways involving the nuclear BAs receptor farnesoid X receptor and the G protein-coupled BAs receptor TGR5/M-BAR have been identified to be the targets of BAs.BAs regulate their own homeostasis via signaling pathways.BAs also affect diverse metabolic pathways including glucose metabolism,lipid metabolism and energy expenditure.This paper suggests the mechanism of controlling metabolism via BA signaling and demonstrates that BA signaling is an attractive therapeutic target of the metabolic syndrome.展开更多
Zinc-α2-glycoprotein(ZAG), encoded by the AZGP1 gene, is a major histocompatibility complex I molecule and a lipid-mobilizing factor. ZAG has been demonstrated to promote lipid metabolism and glucose utilization, and...Zinc-α2-glycoprotein(ZAG), encoded by the AZGP1 gene, is a major histocompatibility complex I molecule and a lipid-mobilizing factor. ZAG has been demonstrated to promote lipid metabolism and glucose utilization, and to regulate insulin sensitivity. Apart from adipose tissue, skeletal muscle, liver, and kidney, ZAG also occurs in brain tissue, but its distribution in brain is debatable. Only a few studies have investigated ZAG in the brain. It has been found in the brains of patients with Krabbe disease and epilepsy, and in the cerebrospinal fluid of patients with Alzheimer disease, frontotemporal lobe dementia, and amyotrophic lateral sclerosis. Both ZAG protein and AZGP1 m RNA are decreased in epilepsy patients and animal models, while overexpression of ZAG suppresses seizure and epileptic discharges in animal models of epilepsy, but knowledge of the specific mechanism of ZAG in epilepsy is limited. In this review, we summarize the known roles and molecular mechanisms of ZAG in lipid metabolism and glucose metabolism, and in the regulation of insulin sensitivity, and discuss the possible mechanisms by which it suppresses epilepsy.展开更多
基金We apologize to those authors whose excellent work could not be cited due to space constraints. This work was supported by the Start-Up Package Fund from Tsinghua University to J.P. and the grant （Grants No. 2010CB912804 and 31030046 to WM） from National Natural Science Foundation of China.
文摘Energy metabolism is significantly reprogrammed in many human cancers, and these alterations confer many advantages to cancer cells, including the pro- motion of biosynthesis, ATP generation, detoxification and support of rapid proliferation. The pentose phos- phate pathway （PPP） is a major pathway for glucose catabolism. The PPP directs glucose flux to its oxi- dative branch and produces a reduced form of nico- tinamide adenine dinucleotide phosphate （NADPH）, an essential reductant in anabolic processes. It has become clear that the PPP plays a critical role in regulating cancer cell growth by supplying cells with not only ribose-5-phosphate but also NADPH for detoxification of intracellular reactive oxygen species, reductive biosynthesis and ribose biogenesis. Thus, alteration of the PPP contributes directly to cell pro- liferation, survival and senescence. Furthermore, recent studies have shown that the PPP is regulated oncogenically and/or metabolically by numerous fac- tors, including tumor suppressors, oncoproteins and intracellular metabolites. Dysregulation of PPP flux dramatically impacts cancer growth and survival. Therefore, a better understanding of how the PPP is reprogrammed and the mechanism underlying the balance between glycolysis and PPP flux in cancer will be valuable in developing therapeutic strategies targeting this pathway.
文摘Helicobacter pylori(H.pylori)is still the most prevalent infection of the world.Colonization of the stomach by this agent will invariably induce chronic gastritis which is a low-grade inflammatory state leading to local complications(peptic ulcer,gastric cancer,lymphoma)and remote manifestations.While H.pylori does not enter circulation,these extragastric manifestations are probably mediated by the cytokines and acute phase proteins produced by the inflammed mucosa.The epidemiologic link between the H.pylori infection and metabolic changes is inconstant and controversial.Growth delay was described mainly in low-income regions with high prevalence of the infection,where probably other nutritional and social factors contribute to it.The timely eradication of the infection will lead to a more healthy development of the young population,along with preventing peptic ulcers and gastric cancer An increase of total,low density lipoprotein and high density liporotein cholesterol levels in some infected people creates an atherogenic lipid profile which could promote atherosclerosis with its complications,myocardial infarction,stroke and peripheral vascular disease.Well designed and adequately powered long-term studies are required to see whether eradication of the infection will prevent these conditions.In case of glucose metabolism,the most consistent association was found between H.pylori and insulin resistance:again,proof that eradication prevents this common metabolic disturbance is expected.The results of eradication with standard regimens in diabetics are significantly worse than in non-diabetic patients,thus,more active regimens must be found to obtain better results.Successful eradication itself led to an increase of body mass index and cholesterol levels in some populations,while in others no such changes were encountered.Uncertainities of the metabolic consequences of H.pylori infection must be clarified in the future.
基金Supported by The China Scholarship CouncilNo.[2014]3012
文摘Glucose metabolism in gastric cancer cells differs from that of normal epithelial cells. Upregulated aerobic glycolysis(Warburg effect) in gastric cancer meeting the demands of cell proliferation is associated with genetic mutations, epigenetic modification and proteomic alteration. Understanding the mechanisms of aerobic glycolysis may contribute to our knowledge of gastric carcinogenesis. Metabolomic studies offer novel, convenient and practical tools in the search for new biomarkers for early detection, diagnosis, prognosis, and chemosensitivity prediction of gastric cancer. Interfering with the process of glycolysis in cancer cells may provide a new and promising therapeutic strategy for gastric cancer. In this article, we present a brief review of recent studies of glucose metabolism in gastric cancer, with primary focus on the clinical applications of new biomarkers and their potential therapeutic role in gastric cancer.
基金supported in part by the New York State Office for People with Developmental Disabilitiesthe Second Affiliated Hospital of the School of Medicine,Zhejiang Universitya grant from the U.S.Alzheimer’s Association(IIRG-10-170405)
文摘Contrary to the previous belief that insulin does not act in the brain, studies in the last three decades have demonstrated important roles of insulin and insulin signal transduction in various functions of the central nervous system. Deregulated brain insulin signaling and its role in molecular pathogenesis have recently been reported in Alzheimer＇s disease （AD）. In this article, we review the roles of brain insulin signaling in memory and cognition, the metabolism of amyloid 13 precursor protein, and tau phosphorylation. We further discuss deficiencies of brain insulin signaling and glucose metabolism, their roles in the development of AD, and recent studies that target the brain insulin signaling pathway for the treatment of AD. It is clear now that deregulation of brain insulin signaling plays an important role in the development of sporadic AD. The brain insulin signaling pathway also offers a promising therapeutic target for treating AD and probably other neurodegenerative disorders.
文摘Background Increasingly, evidence from population, clinic-based and laboratory studies supports an independent association between obstructive sleep apnea syndrome （OSAS） and an increased risk of type 2 diabetes; however, this observation has yet to be replicated in China and the potential mechanisms that link these two conditions are not clear. Methods A total of 179 Han Chinese subjects were enrolled in this study. All subjects underwent polysomnography, the oral glucose tolerance-insulin releasing test （OGTT-IRT） and serum HbAlc measurement. Indexes including homeostasis model assessment-IR （HOMA-IR）, Matsuda index, HOMA-β, early phase insulinogenic index （△I30 / △G30）, AUC-I180 and oral disposition index （DIo） were calculated for the assessment of insulin resistance and pancreatic β-cell function. Results Based on OGTT, 25.4%, 44.6% and 54.5% subjects were diagnosed having glucose metabolic disorders respectively in control, mild to moderate and severe OSAS groups （P 〈0.05）. Serum HbA1c levels were highest in subjects with severe OSAS （P 〈0.05）. In contrast, compared with normal subjects, HOMA-β, △I30/△G30 and DIo were lower in severe OSAS group （P 〈0.05）. In stepwise multiple linear regressions, 0-min glucose and HbAlc were positively correlated with the percentage of total sleep time below an oxyhemoglobin saturation of 90% （T90） （Beta = 0.215 and 0.368, P 〈0.05）; 30-min and 60-min glucose was negatively correlated with the lowest SpO2 （LSpO2） （Beta = -0.214 and -0.241, P 〈0.05）. HOMA-β and Dlowere negatively correlated with T90 （Beta = -0.153 and -0.169, P 〈0.05） while body mass index （BMI） was the only determinant of HOMA-IR and Matsuda index. Conclusions OSAS is associated with impairment in glucose tolerance and pancreatic β-cell function in Han Chinese subjects while insulin sensitivity is mainly determined by obesity.
文摘Recent studies have revealed that bile acids(BAs)are not only facilitators of dietary lipid absorption but also important signaling molecules exerting multiple physiological functions.Some major signaling pathways involving the nuclear BAs receptor farnesoid X receptor and the G protein-coupled BAs receptor TGR5/M-BAR have been identified to be the targets of BAs.BAs regulate their own homeostasis via signaling pathways.BAs also affect diverse metabolic pathways including glucose metabolism,lipid metabolism and energy expenditure.This paper suggests the mechanism of controlling metabolism via BA signaling and demonstrates that BA signaling is an attractive therapeutic target of the metabolic syndrome.
基金supported by the National Natural Science Foundation of China(81771391,81401073)Chongqing Municipal Public Health Bureau,Chongqing People’s Municipal Government(20142026)the Program for Innovative Research Team of Chongqing Kuanren Hospital,China
文摘Zinc-α2-glycoprotein(ZAG), encoded by the AZGP1 gene, is a major histocompatibility complex I molecule and a lipid-mobilizing factor. ZAG has been demonstrated to promote lipid metabolism and glucose utilization, and to regulate insulin sensitivity. Apart from adipose tissue, skeletal muscle, liver, and kidney, ZAG also occurs in brain tissue, but its distribution in brain is debatable. Only a few studies have investigated ZAG in the brain. It has been found in the brains of patients with Krabbe disease and epilepsy, and in the cerebrospinal fluid of patients with Alzheimer disease, frontotemporal lobe dementia, and amyotrophic lateral sclerosis. Both ZAG protein and AZGP1 m RNA are decreased in epilepsy patients and animal models, while overexpression of ZAG suppresses seizure and epileptic discharges in animal models of epilepsy, but knowledge of the specific mechanism of ZAG in epilepsy is limited. In this review, we summarize the known roles and molecular mechanisms of ZAG in lipid metabolism and glucose metabolism, and in the regulation of insulin sensitivity, and discuss the possible mechanisms by which it suppresses epilepsy.
