The Experts below are selected from a list of 34035 Experts worldwide ranked by ideXlab platform
Dwight J Klemm - One of the best experts on this subject based on the ideXlab platform.
-
depletion of camp response element binding protein atf1 inhibits Adipogenic conversion of 3t3 l1 cells ectopically expressing ccaat enhancer binding protein c ebp α c ebp β or pparγ2
Journal of Biological Chemistry, 2006Co-Authors: Dana M Fankell, Paul F Erickson, Susan M Majka, Joseph T Crossno, Dwight J KlemmAbstract:Abstract The differentiation of preadipocytes to adipocytes is orchestrated by the expression of the “master Adipogenic regulators,” CCAAT/enhancer-binding protein (C/EBP) β, peroxisome proliferator-activated receptor γ (PPARγ), and C/EBP α. In addition, activation of the cAMP-response element-binding protein (CREB) is necessary and sufficient to promote Adipogenic conversion and prevent apoptosis of mature adipocytes. In this report we used small interfering RNAto deplete CREB and the closely related factor ATF1 to explore the ability of the master Adipogenic regulators to promote adipogenesis in the absence of CREB and probe the function of CREB in late stages of adipogenesis. Loss of CREB/ATF1 blocked Adipogenic conversion of 3T3-L1 cells in culture or 3T3-F442A cells implanted into athymic mice. Loss of CREB/ATF1 prevented the expression of PPARγ, C/EBP α, and adiponectin and inhibited the loss of Pref-1. Loss of CREB/ATF1 inhibited Adipogenic conversion even in cells ectopically expressing C/EBP α, C/EBP β, or PPARγ2 individually. CREB/ATF1 depletion did not attenuate lipid accumulation in cells expressing both PPARγ2 and C/EBP α, but adiponectin expression was severely diminished. Conversely ectopic expression of constitutively active CREB overcame the blockade of adipogenesis due to depletion of C/EBP β but not due to loss of PPARγ2 or C/EBP α. Depletion of CREB/ATF1 did not suppress the expression of C/EBP β as we had previously observed using dominant negative forms of CREB. Finally results are presented showing that CREB promotes PPARγ2 gene transcription. The results indicate that CREB and ATF1 play a central role in adipogenesis because expression of individual master Adipogenic regulators is unable to compensate for their loss. The data also indicate that CREB not only functions during the initiation of Adipogenic conversion but also at later stages.
-
depletion of camp response element binding protein atf1 inhibits Adipogenic conversion of 3t3 l1 cells ectopically expressing ccaat enhancer binding protein c ebp α c ebp β or pparγ2
Journal of Biological Chemistry, 2006Co-Authors: Keith Fox, Dana M Fankell, Paul F Erickson, Susan M Majka, Joseph T Crossno, Dwight J KlemmAbstract:The differentiation of preadipocytes to adipocytes is orchestrated by the expression of the "master Adipogenic regulators," CCAAT/enhancer-binding protein (C/EBP) beta, peroxisome proliferator-activated receptor gamma (PPARgamma), and C/EBP alpha. In addition, activation of the cAMP-response element-binding protein (CREB) is necessary and sufficient to promote Adipogenic conversion and prevent apoptosis of mature adipocytes. In this report we used small interfering RNA to deplete CREB and the closely related factor ATF1 to explore the ability of the master Adipogenic regulators to promote adipogenesis in the absence of CREB and probe the function of CREB in late stages of adipogenesis. Loss of CREB/ATF1 blocked Adipogenic conversion of 3T3-L1 cells in culture or 3T3-F442A cells implanted into athymic mice. Loss of CREB/ATF1 prevented the expression of PPARgamma, C/EBP alpha, and adiponectin and inhibited the loss of Pref-1. Loss of CREB/ATF1 inhibited Adipogenic conversion even in cells ectopically expressing C/EBP alpha, C/EBP beta, or PPARgamma2 individually. CREB/ATF1 depletion did not attenuate lipid accumulation in cells expressing both PPARgamma2 and C/EBP alpha, but adiponectin expression was severely diminished. Conversely ectopic expression of constitutively active CREB overcame the blockade of adipogenesis due to depletion of C/EBP beta but not due to loss of PPARgamma2 or C/EBP alpha. Depletion of CREB/ATF1 did not suppress the expression of C/EBP beta as we had previously observed using dominant negative forms of CREB. Finally results are presented showing that CREB promotes PPARgamma2 gene transcription. The results indicate that CREB and ATF1 play a central role in adipogenesis because expression of individual master Adipogenic regulators is unable to compensate for their loss. The data also indicate that CREB not only functions during the initiation of Adipogenic conversion but also at later stages.
Jinxiu Huang - One of the best experts on this subject based on the ideXlab platform.
-
Expressions and Regulatory Effects of P38/ERK/JNK Mapks in the Adipogenic Trans-Differentiation of C2C12 Myoblasts.
Cellular physiology and biochemistry : international journal of experimental cellular physiology biochemistry and pharmacology, 2017Co-Authors: Hong Liu, Qi Wang, Jing Wang, Feiyun Yang, Dingbiao Long, Jinxiu HuangAbstract:Background/aims Myoblasts and muscle satellite cells have the potential to transdifferentiate into adipocytes or adipocyte-like cells. Previous studies suggest that mitogen-activated protein kinase (MAPK) is critical to Adipogenic trans-differentiation of muscle cells. ERK1/2, P38 and JNK are three major MAPK family members; their activation and regulatory functions during Adipogenic trans-differentiation of myoblasts are investigated. Methods C2C12 myoblasts were cultured and induced for Adipogenic trans-differentiation. Activation patterns of MAPKs were assayed using protein microarray and Western blot. Three specific MAPK blockers, U0126, SB20358 and SP600125, were used to block ERK1/2, P38 and JNK during trans-differentiation. Cellular adipogenesis was measured using staining and morphological observations of cells and expression changes in Adipogenic genes. Results Inhibitors reduced phosphorylation of corresponding MAPK and produced unique cellular effects. Suppressing P38 promoted Adipogenic trans-differentiation and intensified adipolytic metabolism in differentiated cells. However, inhibition of ERK1/2 had the opposite effects on adipogenesis and no effect on adipolysis. Blocking JNK weakly blocked trans-differentiation but stimulated adipolysis and induced apoptosis. Conclusion Three MAPKs participate in the regulation of myoblast Adipogenic trans-differentiation by controlling Adipogenic and adipolysis metabolism.
-
expressions and regulatory effects of p38 erk jnk mapks in the Adipogenic trans differentiation of c2c12 myoblasts
Cellular Physiology and Biochemistry, 2017Co-Authors: Hong Liu, Qi Wang, Jing Wang, Feiyun Yang, Dingbiao Long, Jinxiu HuangAbstract:Background/aims Myoblasts and muscle satellite cells have the potential to transdifferentiate into adipocytes or adipocyte-like cells. Previous studies suggest that mitogen-activated protein kinase (MAPK) is critical to Adipogenic trans-differentiation of muscle cells. ERK1/2, P38 and JNK are three major MAPK family members; their activation and regulatory functions during Adipogenic trans-differentiation of myoblasts are investigated. Methods C2C12 myoblasts were cultured and induced for Adipogenic trans-differentiation. Activation patterns of MAPKs were assayed using protein microarray and Western blot. Three specific MAPK blockers, U0126, SB20358 and SP600125, were used to block ERK1/2, P38 and JNK during trans-differentiation. Cellular adipogenesis was measured using staining and morphological observations of cells and expression changes in Adipogenic genes. Results Inhibitors reduced phosphorylation of corresponding MAPK and produced unique cellular effects. Suppressing P38 promoted Adipogenic trans-differentiation and intensified adipolytic metabolism in differentiated cells. However, inhibition of ERK1/2 had the opposite effects on adipogenesis and no effect on adipolysis. Blocking JNK weakly blocked trans-differentiation but stimulated adipolysis and induced apoptosis. Conclusion Three MAPKs participate in the regulation of myoblast Adipogenic trans-differentiation by controlling Adipogenic and adipolysis metabolism.
Hong Liu - One of the best experts on this subject based on the ideXlab platform.
-
Expressions and Regulatory Effects of P38/ERK/JNK Mapks in the Adipogenic Trans-Differentiation of C2C12 Myoblasts.
Cellular physiology and biochemistry : international journal of experimental cellular physiology biochemistry and pharmacology, 2017Co-Authors: Hong Liu, Qi Wang, Jing Wang, Feiyun Yang, Dingbiao Long, Jinxiu HuangAbstract:Background/aims Myoblasts and muscle satellite cells have the potential to transdifferentiate into adipocytes or adipocyte-like cells. Previous studies suggest that mitogen-activated protein kinase (MAPK) is critical to Adipogenic trans-differentiation of muscle cells. ERK1/2, P38 and JNK are three major MAPK family members; their activation and regulatory functions during Adipogenic trans-differentiation of myoblasts are investigated. Methods C2C12 myoblasts were cultured and induced for Adipogenic trans-differentiation. Activation patterns of MAPKs were assayed using protein microarray and Western blot. Three specific MAPK blockers, U0126, SB20358 and SP600125, were used to block ERK1/2, P38 and JNK during trans-differentiation. Cellular adipogenesis was measured using staining and morphological observations of cells and expression changes in Adipogenic genes. Results Inhibitors reduced phosphorylation of corresponding MAPK and produced unique cellular effects. Suppressing P38 promoted Adipogenic trans-differentiation and intensified adipolytic metabolism in differentiated cells. However, inhibition of ERK1/2 had the opposite effects on adipogenesis and no effect on adipolysis. Blocking JNK weakly blocked trans-differentiation but stimulated adipolysis and induced apoptosis. Conclusion Three MAPKs participate in the regulation of myoblast Adipogenic trans-differentiation by controlling Adipogenic and adipolysis metabolism.
-
expressions and regulatory effects of p38 erk jnk mapks in the Adipogenic trans differentiation of c2c12 myoblasts
Cellular Physiology and Biochemistry, 2017Co-Authors: Hong Liu, Qi Wang, Jing Wang, Feiyun Yang, Dingbiao Long, Jinxiu HuangAbstract:Background/aims Myoblasts and muscle satellite cells have the potential to transdifferentiate into adipocytes or adipocyte-like cells. Previous studies suggest that mitogen-activated protein kinase (MAPK) is critical to Adipogenic trans-differentiation of muscle cells. ERK1/2, P38 and JNK are three major MAPK family members; their activation and regulatory functions during Adipogenic trans-differentiation of myoblasts are investigated. Methods C2C12 myoblasts were cultured and induced for Adipogenic trans-differentiation. Activation patterns of MAPKs were assayed using protein microarray and Western blot. Three specific MAPK blockers, U0126, SB20358 and SP600125, were used to block ERK1/2, P38 and JNK during trans-differentiation. Cellular adipogenesis was measured using staining and morphological observations of cells and expression changes in Adipogenic genes. Results Inhibitors reduced phosphorylation of corresponding MAPK and produced unique cellular effects. Suppressing P38 promoted Adipogenic trans-differentiation and intensified adipolytic metabolism in differentiated cells. However, inhibition of ERK1/2 had the opposite effects on adipogenesis and no effect on adipolysis. Blocking JNK weakly blocked trans-differentiation but stimulated adipolysis and induced apoptosis. Conclusion Three MAPKs participate in the regulation of myoblast Adipogenic trans-differentiation by controlling Adipogenic and adipolysis metabolism.
Dana M Fankell - One of the best experts on this subject based on the ideXlab platform.
-
depletion of camp response element binding protein atf1 inhibits Adipogenic conversion of 3t3 l1 cells ectopically expressing ccaat enhancer binding protein c ebp α c ebp β or pparγ2
Journal of Biological Chemistry, 2006Co-Authors: Dana M Fankell, Paul F Erickson, Susan M Majka, Joseph T Crossno, Dwight J KlemmAbstract:Abstract The differentiation of preadipocytes to adipocytes is orchestrated by the expression of the “master Adipogenic regulators,” CCAAT/enhancer-binding protein (C/EBP) β, peroxisome proliferator-activated receptor γ (PPARγ), and C/EBP α. In addition, activation of the cAMP-response element-binding protein (CREB) is necessary and sufficient to promote Adipogenic conversion and prevent apoptosis of mature adipocytes. In this report we used small interfering RNAto deplete CREB and the closely related factor ATF1 to explore the ability of the master Adipogenic regulators to promote adipogenesis in the absence of CREB and probe the function of CREB in late stages of adipogenesis. Loss of CREB/ATF1 blocked Adipogenic conversion of 3T3-L1 cells in culture or 3T3-F442A cells implanted into athymic mice. Loss of CREB/ATF1 prevented the expression of PPARγ, C/EBP α, and adiponectin and inhibited the loss of Pref-1. Loss of CREB/ATF1 inhibited Adipogenic conversion even in cells ectopically expressing C/EBP α, C/EBP β, or PPARγ2 individually. CREB/ATF1 depletion did not attenuate lipid accumulation in cells expressing both PPARγ2 and C/EBP α, but adiponectin expression was severely diminished. Conversely ectopic expression of constitutively active CREB overcame the blockade of adipogenesis due to depletion of C/EBP β but not due to loss of PPARγ2 or C/EBP α. Depletion of CREB/ATF1 did not suppress the expression of C/EBP β as we had previously observed using dominant negative forms of CREB. Finally results are presented showing that CREB promotes PPARγ2 gene transcription. The results indicate that CREB and ATF1 play a central role in adipogenesis because expression of individual master Adipogenic regulators is unable to compensate for their loss. The data also indicate that CREB not only functions during the initiation of Adipogenic conversion but also at later stages.
-
depletion of camp response element binding protein atf1 inhibits Adipogenic conversion of 3t3 l1 cells ectopically expressing ccaat enhancer binding protein c ebp α c ebp β or pparγ2
Journal of Biological Chemistry, 2006Co-Authors: Keith Fox, Dana M Fankell, Paul F Erickson, Susan M Majka, Joseph T Crossno, Dwight J KlemmAbstract:The differentiation of preadipocytes to adipocytes is orchestrated by the expression of the "master Adipogenic regulators," CCAAT/enhancer-binding protein (C/EBP) beta, peroxisome proliferator-activated receptor gamma (PPARgamma), and C/EBP alpha. In addition, activation of the cAMP-response element-binding protein (CREB) is necessary and sufficient to promote Adipogenic conversion and prevent apoptosis of mature adipocytes. In this report we used small interfering RNA to deplete CREB and the closely related factor ATF1 to explore the ability of the master Adipogenic regulators to promote adipogenesis in the absence of CREB and probe the function of CREB in late stages of adipogenesis. Loss of CREB/ATF1 blocked Adipogenic conversion of 3T3-L1 cells in culture or 3T3-F442A cells implanted into athymic mice. Loss of CREB/ATF1 prevented the expression of PPARgamma, C/EBP alpha, and adiponectin and inhibited the loss of Pref-1. Loss of CREB/ATF1 inhibited Adipogenic conversion even in cells ectopically expressing C/EBP alpha, C/EBP beta, or PPARgamma2 individually. CREB/ATF1 depletion did not attenuate lipid accumulation in cells expressing both PPARgamma2 and C/EBP alpha, but adiponectin expression was severely diminished. Conversely ectopic expression of constitutively active CREB overcame the blockade of adipogenesis due to depletion of C/EBP beta but not due to loss of PPARgamma2 or C/EBP alpha. Depletion of CREB/ATF1 did not suppress the expression of C/EBP beta as we had previously observed using dominant negative forms of CREB. Finally results are presented showing that CREB promotes PPARgamma2 gene transcription. The results indicate that CREB and ATF1 play a central role in adipogenesis because expression of individual master Adipogenic regulators is unable to compensate for their loss. The data also indicate that CREB not only functions during the initiation of Adipogenic conversion but also at later stages.
Jeong Ho Hong - One of the best experts on this subject based on the ideXlab platform.
-
Phorbaketal A inhibits Adipogenic differentiation through the suppression of PPARγ-mediated gene transcription by TAZ.
European Journal of Pharmacology, 2013Co-Authors: Mi Ran Byun, Cham Han Lee, Jun Ha Hwang, A. Rum Kim, Sung Ah Moon, Mi Kyung Sung, Jung Rae Roh, Eun Sook Hwang, Jeong Ho HongAbstract:Obesity causes several metabolic diseases, including diabetes. Adipogenic differentiation is an important event for fat formation in obesity. Natural compounds that inhibit Adipogenic differentiation are frequently screened to develop therapeutic drugs for treating obesity. Here we investigated the effects of phorbaketal A, a natural marine compound, on Adipogenic differentiation of mesenchymal stem cells. Phorbaketal A significantly inhibited Adipogenic differentiation as indicated by less fat droplets and decreased expression of Adipogenic marker genes. The expression of TAZ (transcriptional coactivator with PDZ-binding motif), an inhibitor of Adipogenic differentiation, significantly increased during Adipogenic differentiation in the presence of phorbaketal A. Phorbaketal A increased the interaction of TAZ and PPARγ to suppress PPARγ (peroxisome proliferator-activated receptor γ) target gene expression. TAZ-depleted cells showed higher Adipogenic potential than that of control cells even in the presence of phorbaketal A. During cellular signaling induced by phorbaketal A, ERK (extracellular signal-regulated kinase) played an important role in Adipogenic suppression; an inhibitor of ERK blocked phorbaketal A-induced Adipogenic suppression. Thus, the results show that phorbaketal A inhibits adipocyte differentiation through TAZ.
-
Idesolide inhibits the Adipogenic differentiation of mesenchymal cells through the suppression of nitric oxide production.
European Journal of Pharmacology, 2012Co-Authors: Jun Ha Hwang, Mi Ran Byun, Cham Han Lee, A. Rum Kim, Sung Ah Moon, Mi Kyung Sung, Eun Sook Hwang, Hyun Jin Park, Sang Hyun Sung, Jeong Ho HongAbstract:Obesity is a major health problem worldwide and can increase the risk for several chronic diseases, including diabetes and cardiovascular disease. In this study, we screened small compounds isolated from natural products for the development of an anti-obesity drug. Among them, idesolide, a spiro compound isolated from the fruits of Idesia polycarpa Maxim, showed a significant suppression of the Adipogenic differentiation in mesenchymal cells, as indicated by the decrease in fat droplets and expression of Adipogenic marker genes such as aP2 and adiponectin. Idesolide inhibits the PPARγ-mediated gene transcription in a dose-dependent manner, revealed by luciferase reporter gene assay. During Adipogenic differentiation, idesolide inhibits nitric oxide production through the suppression of iNOS expression, and the increased Adipogenic differentiation by arginine, the substrate for NOS, is significantly inhibited by idesolide, suggesting that the inhibition of nitric oxide production plays a major role in idesolide-induced Adipogenic suppression. Taken together, the results reveal that idesolide has anti-Adipogenic activity and highlight its potential in the prevention and treatment of obesity.
-
Augmentation of PPARγ-TAZ interaction contributes to the anti-Adipogenic activity of KR62980
Biochemical pharmacology, 2009Co-Authors: Hana Jung, Jeong Ho Hong, Mi Sook Lee, Eun Jung Jang, Jin Hee Ahn, Nam Sook Kang, Sung Eun Yoo, Myung Ae Bae, Eun Sook HwangAbstract:Abstract Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated transcription factor that plays a pivotal role in the modulation of gene expression involved in adipocyte differentiation and insulin sensitivity. It has been previously established that thiazolidinedione (TZD) PPARγ ligands such as rosiglitazone have potent anti-diabetic and Adipogenic activities. A novel non-TZD ligand for PPARγ, KR62980 has recently been characterized to increase insulin sensitivity and to be weakly Adipogenic in 3T3-L1 cells or anti-Adipogenic in rosiglitazone-induced adipocyte differentiation. In this study, we have confirmed that KR62980 substantially suppresses rosiglitazone-induced adipocyte differentiation and attenuates Adipogenic gene expression via an induced reduction in PPARγ activity. KR62980 increased the nuclear localization of TAZ, a PPARγ suppressor, and also enhanced the interaction between PPARγ and TAZ, thus resulting in the TAZ-mediated suppression of PPARγ activity. Furthermore, KR62980 failed to suppress PPARγ-mediated Adipogenic gene expression and adipocyte differentiation in TAZ knockdown 3T3-L1 cells, thus indicating a TAZ-dependent suppressive activity of KR62980 on PPARγ-mediated function. These findings strongly suggest that the novel PPARγ ligand, KR62980, may prove to be beneficial to anti-Adipogenic function through the suppression of PPARγ-mediated adipocyte differentiation by activating TAZ.
