Peroxisome proliferator activated receptor-γ (PPARγ), a transcription factor of the nuclear receptor superfamily plays a significant role in colorectal cancer pathogenesis. In most experimental systems PPARγ activa...Peroxisome proliferator activated receptor-γ (PPARγ), a transcription factor of the nuclear receptor superfamily plays a significant role in colorectal cancer pathogenesis. In most experimental systems PPARγ activation has tumor suppressing effects in the colon. PPARγ is regulated at multiple levels by the ubiquitin-proteasome system (UPS). At a first level, UPS regulates PPARγ transcription. This regulation involves both PPARγ transcription specific factors and the general transcription machinery. At a second level UPS regulates PPARγ and its co-factors themselves, as PPARγ and many co-factors are proteasome substrates. At a third level of regulation, transduction pathways working in parallel but also having interrelations with PPARγ are regulated by the UPS, creating a network of regulation in the colorectal carcinogenesisrelated pathways that are under UPS control. Activation of PPARγ transcription by direct pharmacologic activators and by stabilization of its molecule by proteasome inhibitors could be strategies to be exploited in colorectal cancer treatment.展开更多
Summary： The role of protease activated receptor-2 （PAR-2） in the renal tubulointerstitial lesion induced by unilateral ureteral obstruction （UUO） was explored. Mice were sacrificed on the day 1, 3, 5, 7, 10, 14 ...Summary： The role of protease activated receptor-2 （PAR-2） in the renal tubulointerstitial lesion induced by unilateral ureteral obstruction （UUO） was explored. Mice were sacrificed on the day 1, 3, 5, 7, 10, 14 and 21 after UUO. The expression of PAR-2 mRNA and protein and a-smooth muscle actin （α-SMA） protein in tubuloin,terstitium was detected by RT-PCR and immunohistochemistry at each time point, respedtively. The results showed that the PAR-2 expression in renal tubulointerstitium was increased progressively starting from 24 h to the day 14 post-ligation, and it was significantly associated with the relative volume of interstitium and the positive area of α-SMA. PAR-2 was mainly expressed in renal tubule epithelial cells, especially in proximal tubular cells. It also located in renal capillary ansa, interstitial infiltrate cells and fibroblasts. It was concluded that PAR-2 was active in interstitial and tubular cells in the early phase of fibrotic process and played an important role in mediating the tubulointerstitial lesion after UUO.展开更多
AIM:To investigate the regulation of mindin expression and the signaling pathway involved during inflammation.METHODS:C57BL/6 mice were treated with 3% dextran sulfate sodium (DSS) in drinking water for 6 d to induce ...AIM:To investigate the regulation of mindin expression and the signaling pathway involved during inflammation.METHODS:C57BL/6 mice were treated with 3% dextran sulfate sodium (DSS) in drinking water for 6 d to induce acute colitis,and then the colon was harvested for histological analysis or for RNA isolation.mRNA expression of mindin and nuclear factor (NF)-κB p65 was analyzed by quantitative real time polymerase chain reaction (RT-PCR) and mindin expression construct was conf irmed by Western blotting.Mouse macrophage and intestinal epithelial lineage cells were stimulated with different cytokines and toll-like receptor (TLR) ligands,before pNF-κB-luciferase activity was assessed using the Dual-Luciferase reporter assay system.RESULTS:mRNA expression of mindin was upregulated 4.7 ± 1.1 fold compared with the baseline during DSS-induced intestinal inflammation in the mice.Stimulation with CpG-ODN (a known TLR-9 ligand) induced 4.2 ± 0.3 fold upregulation of mindin expression in RAW 264.7 cells.Full-length of mindin was cloned from cDNA of mouse mesenteric lymph node,then the pCMV-Mindin-Flag expression vector was established and the protein expression level was confi rmed.Transfection of the mindin construct and stimulation with CpG-ODN signifi cantly increased the NF-κB-luciferase activity by 2.5 ± 0.3 and 4.5 ± 0.5 fold in RAW264.7 and CMT93 cells,respectively (P < 0.01).CONCLUSION:Mindin expression is upregulated during intestinal inflammation and may induce NF-κB promoter activation in a TLR-9 mediated manner.展开更多
Background Protease activated receptor-2 is cleaved and activated by trypsin or mast cell tryptase and may play an important role in inflammation. However, it is unknown whetehr PAR-2 can mediate tryptase-induced infl...Background Protease activated receptor-2 is cleaved and activated by trypsin or mast cell tryptase and may play an important role in inflammation. However, it is unknown whetehr PAR-2 can mediate tryptase-induced inflammatory reaction. This study was conduct to investigate wheter PAR-2 could be the activated by mast cell tryptase and medicated the tryptase induced interleukin-8 expression in endothelial cells. Methods Protease activated receptor-2 expression was found in endothelial cell lines ECV304 cell by reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting. Interleukin-8 stimulated by purified human mast cell tryptase was determined by RT-PCR and enzyme linked immunosorbent assay （ELISA）. Data were analysed by the S-N-K one-way ANOVA test. Results The present study shows that mRNA and protein of protease activated receptor-2 could be expressed in ECV304 cells, and tryptase upregulated the expression levels of both interleukin-8 mRNA and protein. The increased expression of interleukin-8 was inhibited by an antiprotease activated receptor-2 monoclonal antibody, SAM11. An additional band was observed by Western blotting after the incubation of ECV304 cells with tryptase for 2 hours, which suggested that protease activated receptor-2 was activated. Conclusion Protease activated receptor-2 can mediate the mast cell tryptase stimulated expression of interleukin-8 in ECV304 cell.展开更多
Studies concerning the pathophysiological connection between obesity and osteoporosis are currently an intriguing area of research.Although the onset of these two diseases can occur in a different way,recent studies h...Studies concerning the pathophysiological connection between obesity and osteoporosis are currently an intriguing area of research.Although the onset of these two diseases can occur in a different way,recent studies have shown that obesity and osteoporosis share common genetic and environmental factors.Despite being a risk factor for health,obesity has traditionally been considered positive to bone because of beneficial effect of mechanical loading,exerted by high body mass,on bone formation.However,contrasting studies have not achieved a clear consensus,suggesting instead that excessive fat mass derived from obesity condition may not protect against osteoporosis or,even worse,could be rather detrimental to bone.On the other hand,it is hitherto better established that,since adipocytes and osteoblasts are derived from a common mesenchymal stem cell precursor,molecules that lead to osteoblastogenesis inhibit adipogenesis and vice versa.Here we will discuss the role of the key molecules regulating adipocytes and osteoblasts differentiation,which are peroxisome proliferators activated receptor-γand Wnts,respectively.In particular,wewill focus on the role of both canonical and non-canonical Wnt signalling,involved in mesenchymal cell fate regulation.Moreover,at present there are no experimental data that relate any influence of the Wnt inhibitor Sclerostin to adipogenesis,although it is well known its role on bone metabolism.In addition,the most common pathological condition in which there is a simultaneous increase of adiposity and decrease of bone mass is menopause.Given that postmenopausal women have high Sclerostin level inversely associated with circulating estradiol level and since the sex hormone replacement therapy has proved to be effective in attenuating bone loss and reversing menopause-related obesity,we hypothesize that Sclerostin contribution in adipogenesis could be an active focus of research in the coming years.展开更多
Alcohol-induced fatty liver (steatosis) was believed to result from excessive generation of reducing equivalents from ethanol metabolism, thereby enhancing fat accumulation. Recent findings have revealed a more comple...Alcohol-induced fatty liver (steatosis) was believed to result from excessive generation of reducing equivalents from ethanol metabolism, thereby enhancing fat accumulation. Recent findings have revealed a more complex picture in which ethanol oxidation is still required, but specific transcription as well as humoral factors also have important roles. Transcription factors involved include the sterol regulatory element binding protein 1 (SREBP-1) which is activated to induce genes that regulate lipid biosynthesis. Conversely, ethanol consumption causes a general down-regulation of lipid (fatty acid) oxidation, a reflection of inactivation of the peroxisome proliferator- activated receptor-alpha (PPAR-α) that regulates genes involved in fatty acid oxidation. A third transcription factor is the early growth response-1 (Egr-1), which is strongly induced prior to the onset of steatosis. The activities of all these factors are governed by that of the principal regulatory enzyme, AMP kinase. Important humoral factors, including adiponectin, and tumor necrosis factor-α (TNF-α), also regulate alcohol-induced steatosis. Their levels are affected by alcohol consumption and by each other. This review will summarize the actions of these proteins in ethanol-elicited fatty liver. Because steatosis is now regarded as a significant risk factor for advanced liver pathology, an understanding of the molecular mechanisms in its etiology is essential for development of effective therapies.展开更多
Background The cannabinoid receptor-2 （CB2） is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist （AM630） on receptor activator of nuclear factor kappa B （RANK）...Background The cannabinoid receptor-2 （CB2） is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist （AM630） on receptor activator of nuclear factor kappa B （RANK） ligand （RANKL）induced osteoclast differentiation and the underlying signaling pathway using a monocyte-macrophage cell line-RAW264.7.Methods RAW264.7 was cultured with RANKL for 6 days and then treated with AM630 for 24 hours. Mature osteoclasts were measured by tartrate-resistant acid phosphatase （TRAP） staining using a commercial kit. Total ribonucleic acid （RNA）was isolated and real-time reverse transcriptase-polymerase chain reaction （RT-PCR） was done to examine the expression of RANK, cathepsin K （CPK） and nuclear factor kappa B （NF-κB）. The extracellular signal-regulated kinase （ERK）,phosphorylation of ERK （P-ERK） and NF-κB production were tested by Western blotting. The effect of AM630 on RAW264.7 viability was determined using the 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazoliumbromide （MTT） assay.Results AM630 did not affect the viability of RAW264.7. However, this CB2 selective antagonist markedly inhibited osteoclast formation and the inhibition rate was dose-dependent. The dose of 〉100 nmol/L could reduce TRAP positive cells to the levels that were significantly lower than the control. AM630 suppressed the expression of genes associated with osteoclast differentiation and activation, such as RANK and CPK. An analysis of a signaling pathway showed that AM630 inhibited the RANKL-induced activation of ERK, but not NF-κB.Conclusion AM630 could inhibit the osteoclastogenesis from RAW264.7 induced with RANKL.展开更多
This study was aimed to explore the associations between the combined effects of several polymorphisms in the PPAR-γ and RXR-α gene and environmental factors with the risk of metabolic syndrome by back-error propaga...This study was aimed to explore the associations between the combined effects of several polymorphisms in the PPAR-γ and RXR-α gene and environmental factors with the risk of metabolic syndrome by back-error propaga- tion artificial neural network （BPANN）. We established the model based on data gathered from metabolic syndrome patients （n = 1012） and normal controls （n = 1069） by BPANN. Mean impact value （MIV） for each input variable was calculated and the sequence of factors was sorted according to their absolute MIVs. Generalized multifactor dimensionality reduction （GMDR） confirmed a joint effect of PPAR-9＂ and RXR-a based on the results from BPANN. By BPANN analysis, the sequences according to the importance of metabolic syndrome risk fac- tors were in the order of body mass index （BMI）, serum adiponectin, rs4240711, gender, rs4842194, family history of type 2 diabetes, rs2920502, physical activity, alcohol drinking, rs3856806, family history of hypertension, rs1045570, rs6537944, age, rs17817276, family history of hyperlipidemia, smoking, rs1801282 and rs3132291. However, no polymorphism was statistically significant in multiple logistic regression analysis. After controlling for environmental factors, A1, A2, B1 and B2 （rs4240711, rs4842194, rs2920502 and rs3856806） models were the best models （cross-validation consistency 10/10, P = 0.0107） with the GMDR method. In conclusion, the interaction of the PPAR-γ and RXR-α gene could play a role in susceptibility to metabolic syndrome. A more realistic model is obtained by using BPANN to screen out determinants of diseases of multiple etiologies like metabolic syndrome.展开更多
The possibility that a recombinant protein vaccine based on xenogeneic homologous FGFR-1 of chicken induces production of autoantibodies against self-FGFR-1 in BALB/c mice was examined by using ELISA, Western blot ana...The possibility that a recombinant protein vaccine based on xenogeneic homologous FGFR-1 of chicken induces production of autoantibodies against self-FGFR-1 in BALB/c mice was examined by using ELISA, Western blot analysis and ELISPOT assay respectively. Autoantibodies against mouse FGFR-1 were identified by Western blot analysis and ELISA. Compared with the two control groups, the number of APBCs, which were detected by ELISPOT assay, was significantly in- creased in the spleens of mice immunized with cFR1 （P〈0.05）. IgG1 and IgG2b, which were detected by ELISA, were the major subclasses and were substantially increased in response to chicken FGFR-1 when compared with control group. The recombinant chicken FGFR-1 protein used as a vaccine can induce autoantibodies against self-FGFR-1 in mice and provide a basis for the active immunotherapy of tumor angiogenesis.展开更多
Background Our previous papers indicate that flurbiprofen axetil （FA）, a cyclooxygenase inhibitor, is a promising therapeutic strategy for cerebral ischemia in rats. This study aimed to investigate whether FA could ...Background Our previous papers indicate that flurbiprofen axetil （FA）, a cyclooxygenase inhibitor, is a promising therapeutic strategy for cerebral ischemia in rats. This study aimed to investigate whether FA could promote a neuroprotective effect by activation of peroxisome proliferator-activated receptor-y （PPAR-y） after focal cerebral ischemia in rats. Methods Totally 48 male Sprague-Dawley （SD） rats were randomly assigned into six groups （n=8 in each group）： animals in group ischemia/reperfusion （I/R） only received 120-minute transient middle cerebral artery occlusion （tMCAO）; animals in group I/R ＋FA were administered FA （10 mg/kg） by caudal vein just after 120-minute tMCAO; animals in group I/R ＋FA＋GW9662 were administered GW9662 （a PPAR-Y inhibitor, 1 mg/kg） intraperitoneally 30 minutes before cerebral ischemia onset and FA （10 mg/kg） by caudal vein just after 120-minute tMCAO; animals in group I/R ＋GW9662 were administered GW9662 （1 mg/kg） intraperitoneally 30 minutes before cerebral ischemia onset; animals in group I/R ＋DMSO were administered 3% DMSO （vehicle of GW9662, 1 ml/kg） intraperitoneally 30 minutes before cerebral ischemia onset; animals in sham group experienced the identical surgery apart from the insertion of the nylon filament. The neurologic deficit score （NDS） were performed at 72 hours after reperfusion, and then mean brain infarct volume percentage （MBIVP） was determined with 2,3,5-triphenyltetrazolium chloride （TTC） 10 g/L staining. Results NDS was significantly increased in group I/R＋FA （12.0 （10.0-15.0））, group I/R＋FA＋GW9662 （10.0 （8.0-12.0））, and in group I/R＋FA＋DMSO （12.0 （9.0-14.0）） at 72 hours after reperfusion compared with those in group I/R （7.5 （6.0-10.0））. NDS was conspicuously different between group I/R＋FA （12.0 （10.0-15.0）） and group I/R＋FA＋GW9662 （10.0 （8.0-12.0））. MBIVP in group I/R （（45.82±8.83）%） was significantly greater than that in group I/R＋FA （（23.52±9.90）%）, group I/R＋FA＋GW9662 （（33.17±7.15）%）; MBIVP in group I/R＋FA （（23.52±9.90）%） was significantly smaller than that in group I/R＋FA＋GW9662 （（33.17±7.15）%）. Conclusions FA confers the neuroprotective effect on tMCAO in rats and the selective PPAR-Y antagonist GW9662 attenuates the effect of FA. FA could promote a neuroprotective effect by, or in part, activation of PPAR-y after focal cerebral ischemia in rats.展开更多
MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington＇s disease mouse models and patients is decreased. However, the effects of microRNA-124 on th...MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington＇s disease mouse models and patients is decreased. However, the effects of microRNA-124 on the progression of Huntington＇s disease have not been reported. Results from this study showed that microRNA-124 increased the latency to fall for each R6/2 Hunting- ton＇s disease transgenic mouse in the rotarod test. 5-Bromo-2＇-deoxyuridine （BrdU） staining of the striatum shows an increase in neurogenesis. In addition, brain-derived neurotrophic factor and peroxisome proliferator-activated receptor gamma coactivator 1-alpha protein levels in the striatum were increased and SRY-related HMG box transcription factor 9 protein level was de- creased. These findings suggest that microRNA-124 slows down the progression of Huntington＇s disease possibly through its important role in neuronal differentiation and survival.展开更多
Accumulating evidence suggests that the Thl immune .response induced by various antigens such as oxidized low density lipoprotein （ox-LDL） and heat shock proteins （HSPs） play a key role in the process of atheroscl...Accumulating evidence suggests that the Thl immune .response induced by various antigens such as oxidized low density lipoprotein （ox-LDL） and heat shock proteins （HSPs） play a key role in the process of atherosclerosis.1Dendritic cells （DCs） are the most potent antigen-presenting cells （APCs） in the body with the unique ability to initiate a primary immune response to certain antigens by the activation of ＂naive＂ T cells.2 The maturation of DC with the upregulation of costimulatory molecules such as CD83, CD40, CD86, and major histocompatibility complex （MHC） class molecules such as human leukocyte antigen （HLA）-DR, is required for DC to activate T cells. Pathologic studies have shown that immature DCs are present in normal arterial while abundant mature DCs clustered with T cells could be visualized in atherogenic vessels suggesting that DC 3 maturation is linked to the progression of atherosclerosls. Peroxisome proliferator-activated receptors （PPARs） a, one member of the family of PPARs, was found to have favorable effects on slowing the progression of atherosclerosis and reducing the risk of coronary heart disease in high-risk patients independent from their metabolism effects.4＇5 Furthermore, PPAR-α is also expressed on monocytes and monocyte-derived DCs.6 The effects of PPAR-α on DCs maturation and immune function remain unknown now, we therefore observed the effects of fenofibrate, a PPAR-α agonist, on the maturation and immune function of oxidized LDL-treated DCs in this study.展开更多
Objective： To explore the molecular mechanism of puerarin （Pue） in improving insulin resistance through observing its effect on the insulin resistance of 3T3-Li lipocyte induced by free fatty acid （FFA）. Methods...Objective： To explore the molecular mechanism of puerarin （Pue） in improving insulin resistance through observing its effect on the insulin resistance of 3T3-Li lipocyte induced by free fatty acid （FFA）. Methods： 3T3-L1 preadipocyte was induced by a culture solution containing insulin, isobutyo-menthyl-xanthine, and dexamethasone to mature lipocyte, and it was divided into six groups： the control group （normal cells）, the model group （untreated model cells）, and the four drug treatment group exposed to dimethyl biguanide （Met group）, high- dose pueradn （PueH group）, low-dose puerarin （PueL group）, and propylene glycol （PG group）, respectively. Mature lipocytes in various groups, except those in the normal group, were established into insulin resistance model by FFA induction and treated respectively with corresponding drugs. Peroxisome proliferator-activated receptor- γ （PPAR- γ） mRNA expressions at the fourth, sixth, and eighth day were observed using reverse transcription polymerase chain reaction （RT-PCR）; glucose transportation in various groups were observed by 2-deoxy-[3H]-D-glucose intake method; mRNA expression of Cbl binding protein （CAP） was determined by RT-PCR; and glucose transporter-4 （Glut-4） transposition was detected by immune-fluorescence method. Results： PPAR- γmRNA expression increased gradually, and it showed lower levels at the fourth, sixth, and eighth day in all treatment groups than that in the model group. Glucose transportation determination showed that the transportation in the model group was 2.23 ± 0.63, significantly lower than that in the normal group 5.05 ± 0.66 （P〈0.01）; as compared with the model group, they were significantly higher in the PueH and the PueL groups. In addition, the CAP mRNA expression and membranous distribution of Glut-4 were higher in the two Pue treated groups than those in the model group, respectively. Conclusion： Pue could markedly improve the insulin resistance of 3T3-L1 lipocyte, which is realized possibly by way of inactivating CAP path, promoting Glut-4 transposition to cell membrane to increase the transportation of glucose.展开更多
文摘Peroxisome proliferator activated receptor-γ (PPARγ), a transcription factor of the nuclear receptor superfamily plays a significant role in colorectal cancer pathogenesis. In most experimental systems PPARγ activation has tumor suppressing effects in the colon. PPARγ is regulated at multiple levels by the ubiquitin-proteasome system (UPS). At a first level, UPS regulates PPARγ transcription. This regulation involves both PPARγ transcription specific factors and the general transcription machinery. At a second level UPS regulates PPARγ and its co-factors themselves, as PPARγ and many co-factors are proteasome substrates. At a third level of regulation, transduction pathways working in parallel but also having interrelations with PPARγ are regulated by the UPS, creating a network of regulation in the colorectal carcinogenesisrelated pathways that are under UPS control. Activation of PPARγ transcription by direct pharmacologic activators and by stabilization of its molecule by proteasome inhibitors could be strategies to be exploited in colorectal cancer treatment.
文摘Summary： The role of protease activated receptor-2 （PAR-2） in the renal tubulointerstitial lesion induced by unilateral ureteral obstruction （UUO） was explored. Mice were sacrificed on the day 1, 3, 5, 7, 10, 14 and 21 after UUO. The expression of PAR-2 mRNA and protein and a-smooth muscle actin （α-SMA） protein in tubuloin,terstitium was detected by RT-PCR and immunohistochemistry at each time point, respedtively. The results showed that the PAR-2 expression in renal tubulointerstitium was increased progressively starting from 24 h to the day 14 post-ligation, and it was significantly associated with the relative volume of interstitium and the positive area of α-SMA. PAR-2 was mainly expressed in renal tubule epithelial cells, especially in proximal tubular cells. It also located in renal capillary ansa, interstitial infiltrate cells and fibroblasts. It was concluded that PAR-2 was active in interstitial and tubular cells in the early phase of fibrotic process and played an important role in mediating the tubulointerstitial lesion after UUO.
基金Supported by National Natural Science Foundation of China,No. 30750013
文摘AIM:To investigate the regulation of mindin expression and the signaling pathway involved during inflammation.METHODS:C57BL/6 mice were treated with 3% dextran sulfate sodium (DSS) in drinking water for 6 d to induce acute colitis,and then the colon was harvested for histological analysis or for RNA isolation.mRNA expression of mindin and nuclear factor (NF)-κB p65 was analyzed by quantitative real time polymerase chain reaction (RT-PCR) and mindin expression construct was conf irmed by Western blotting.Mouse macrophage and intestinal epithelial lineage cells were stimulated with different cytokines and toll-like receptor (TLR) ligands,before pNF-κB-luciferase activity was assessed using the Dual-Luciferase reporter assay system.RESULTS:mRNA expression of mindin was upregulated 4.7 ± 1.1 fold compared with the baseline during DSS-induced intestinal inflammation in the mice.Stimulation with CpG-ODN (a known TLR-9 ligand) induced 4.2 ± 0.3 fold upregulation of mindin expression in RAW 264.7 cells.Full-length of mindin was cloned from cDNA of mouse mesenteric lymph node,then the pCMV-Mindin-Flag expression vector was established and the protein expression level was confi rmed.Transfection of the mindin construct and stimulation with CpG-ODN signifi cantly increased the NF-κB-luciferase activity by 2.5 ± 0.3 and 4.5 ± 0.5 fold in RAW264.7 and CMT93 cells,respectively (P < 0.01).CONCLUSION:Mindin expression is upregulated during intestinal inflammation and may induce NF-κB promoter activation in a TLR-9 mediated manner.
基金This study was supported by grants from National Natural ScienceFoundation of China(No.30470689), and the Science DevelopingFoundation of Shanghai Medical Healthy Bureau (No.034087)
文摘Background Protease activated receptor-2 is cleaved and activated by trypsin or mast cell tryptase and may play an important role in inflammation. However, it is unknown whetehr PAR-2 can mediate tryptase-induced inflammatory reaction. This study was conduct to investigate wheter PAR-2 could be the activated by mast cell tryptase and medicated the tryptase induced interleukin-8 expression in endothelial cells. Methods Protease activated receptor-2 expression was found in endothelial cell lines ECV304 cell by reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting. Interleukin-8 stimulated by purified human mast cell tryptase was determined by RT-PCR and enzyme linked immunosorbent assay （ELISA）. Data were analysed by the S-N-K one-way ANOVA test. Results The present study shows that mRNA and protein of protease activated receptor-2 could be expressed in ECV304 cells, and tryptase upregulated the expression levels of both interleukin-8 mRNA and protein. The increased expression of interleukin-8 was inhibited by an antiprotease activated receptor-2 monoclonal antibody, SAM11. An additional band was observed by Western blotting after the incubation of ECV304 cells with tryptase for 2 hours, which suggested that protease activated receptor-2 was activated. Conclusion Protease activated receptor-2 can mediate the mast cell tryptase stimulated expression of interleukin-8 in ECV304 cell.
文摘Studies concerning the pathophysiological connection between obesity and osteoporosis are currently an intriguing area of research.Although the onset of these two diseases can occur in a different way,recent studies have shown that obesity and osteoporosis share common genetic and environmental factors.Despite being a risk factor for health,obesity has traditionally been considered positive to bone because of beneficial effect of mechanical loading,exerted by high body mass,on bone formation.However,contrasting studies have not achieved a clear consensus,suggesting instead that excessive fat mass derived from obesity condition may not protect against osteoporosis or,even worse,could be rather detrimental to bone.On the other hand,it is hitherto better established that,since adipocytes and osteoblasts are derived from a common mesenchymal stem cell precursor,molecules that lead to osteoblastogenesis inhibit adipogenesis and vice versa.Here we will discuss the role of the key molecules regulating adipocytes and osteoblasts differentiation,which are peroxisome proliferators activated receptor-γand Wnts,respectively.In particular,wewill focus on the role of both canonical and non-canonical Wnt signalling,involved in mesenchymal cell fate regulation.Moreover,at present there are no experimental data that relate any influence of the Wnt inhibitor Sclerostin to adipogenesis,although it is well known its role on bone metabolism.In addition,the most common pathological condition in which there is a simultaneous increase of adiposity and decrease of bone mass is menopause.Given that postmenopausal women have high Sclerostin level inversely associated with circulating estradiol level and since the sex hormone replacement therapy has proved to be effective in attenuating bone loss and reversing menopause-related obesity,we hypothesize that Sclerostin contribution in adipogenesis could be an active focus of research in the coming years.
基金Supported by New Research Grant from the University of Nebraska Medical Center, the NIAAA, and Medical Research Funds from the Department of Veterans Affairs, United States
文摘Alcohol-induced fatty liver (steatosis) was believed to result from excessive generation of reducing equivalents from ethanol metabolism, thereby enhancing fat accumulation. Recent findings have revealed a more complex picture in which ethanol oxidation is still required, but specific transcription as well as humoral factors also have important roles. Transcription factors involved include the sterol regulatory element binding protein 1 (SREBP-1) which is activated to induce genes that regulate lipid biosynthesis. Conversely, ethanol consumption causes a general down-regulation of lipid (fatty acid) oxidation, a reflection of inactivation of the peroxisome proliferator- activated receptor-alpha (PPAR-α) that regulates genes involved in fatty acid oxidation. A third transcription factor is the early growth response-1 (Egr-1), which is strongly induced prior to the onset of steatosis. The activities of all these factors are governed by that of the principal regulatory enzyme, AMP kinase. Important humoral factors, including adiponectin, and tumor necrosis factor-α (TNF-α), also regulate alcohol-induced steatosis. Their levels are affected by alcohol consumption and by each other. This review will summarize the actions of these proteins in ethanol-elicited fatty liver. Because steatosis is now regarded as a significant risk factor for advanced liver pathology, an understanding of the molecular mechanisms in its etiology is essential for development of effective therapies.
基金This work was supported by the grants from Jiangsu Province Key Medical Center （No. ZX200608）, the National Nature Science Foundation of China （No. 30672140, No. 81071451）, the Colleges and Universities Natural Science Foundation in Jiangsu Province （No. 10KJB320019）, the Key Project Surpported by the Medical Science and Technology Department Foundation, Jiangsu Province, Department of Health （No. H201012） and the Social Development Projects in Suzhou （No. SS08020）.
文摘Background The cannabinoid receptor-2 （CB2） is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist （AM630） on receptor activator of nuclear factor kappa B （RANK） ligand （RANKL）induced osteoclast differentiation and the underlying signaling pathway using a monocyte-macrophage cell line-RAW264.7.Methods RAW264.7 was cultured with RANKL for 6 days and then treated with AM630 for 24 hours. Mature osteoclasts were measured by tartrate-resistant acid phosphatase （TRAP） staining using a commercial kit. Total ribonucleic acid （RNA）was isolated and real-time reverse transcriptase-polymerase chain reaction （RT-PCR） was done to examine the expression of RANK, cathepsin K （CPK） and nuclear factor kappa B （NF-κB）. The extracellular signal-regulated kinase （ERK）,phosphorylation of ERK （P-ERK） and NF-κB production were tested by Western blotting. The effect of AM630 on RAW264.7 viability was determined using the 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazoliumbromide （MTT） assay.Results AM630 did not affect the viability of RAW264.7. However, this CB2 selective antagonist markedly inhibited osteoclast formation and the inhibition rate was dose-dependent. The dose of 〉100 nmol/L could reduce TRAP positive cells to the levels that were significantly lower than the control. AM630 suppressed the expression of genes associated with osteoclast differentiation and activation, such as RANK and CPK. An analysis of a signaling pathway showed that AM630 inhibited the RANKL-induced activation of ERK, but not NF-κB.Conclusion AM630 could inhibit the osteoclastogenesis from RAW264.7 induced with RANKL.
基金supported by the National Natural Science Foundation of China Grant No.30771858Jiangsu Provincial Natural Science Foundation Grant No.BK2007229Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘This study was aimed to explore the associations between the combined effects of several polymorphisms in the PPAR-γ and RXR-α gene and environmental factors with the risk of metabolic syndrome by back-error propaga- tion artificial neural network （BPANN）. We established the model based on data gathered from metabolic syndrome patients （n = 1012） and normal controls （n = 1069） by BPANN. Mean impact value （MIV） for each input variable was calculated and the sequence of factors was sorted according to their absolute MIVs. Generalized multifactor dimensionality reduction （GMDR） confirmed a joint effect of PPAR-9＂ and RXR-a based on the results from BPANN. By BPANN analysis, the sequences according to the importance of metabolic syndrome risk fac- tors were in the order of body mass index （BMI）, serum adiponectin, rs4240711, gender, rs4842194, family history of type 2 diabetes, rs2920502, physical activity, alcohol drinking, rs3856806, family history of hypertension, rs1045570, rs6537944, age, rs17817276, family history of hyperlipidemia, smoking, rs1801282 and rs3132291. However, no polymorphism was statistically significant in multiple logistic regression analysis. After controlling for environmental factors, A1, A2, B1 and B2 （rs4240711, rs4842194, rs2920502 and rs3856806） models were the best models （cross-validation consistency 10/10, P = 0.0107） with the GMDR method. In conclusion, the interaction of the PPAR-γ and RXR-α gene could play a role in susceptibility to metabolic syndrome. A more realistic model is obtained by using BPANN to screen out determinants of diseases of multiple etiologies like metabolic syndrome.
基金This work was supported by a 2003 grant of Hainan Pro-vincial Natural Sciences Foundation (No.30321)
文摘The possibility that a recombinant protein vaccine based on xenogeneic homologous FGFR-1 of chicken induces production of autoantibodies against self-FGFR-1 in BALB/c mice was examined by using ELISA, Western blot analysis and ELISPOT assay respectively. Autoantibodies against mouse FGFR-1 were identified by Western blot analysis and ELISA. Compared with the two control groups, the number of APBCs, which were detected by ELISPOT assay, was significantly in- creased in the spleens of mice immunized with cFR1 （P〈0.05）. IgG1 and IgG2b, which were detected by ELISA, were the major subclasses and were substantially increased in response to chicken FGFR-1 when compared with control group. The recombinant chicken FGFR-1 protein used as a vaccine can induce autoantibodies against self-FGFR-1 in mice and provide a basis for the active immunotherapy of tumor angiogenesis.
基金This study was supported by a grant from the National Natural Science Foundation of China （No. 30872445）.
文摘Background Our previous papers indicate that flurbiprofen axetil （FA）, a cyclooxygenase inhibitor, is a promising therapeutic strategy for cerebral ischemia in rats. This study aimed to investigate whether FA could promote a neuroprotective effect by activation of peroxisome proliferator-activated receptor-y （PPAR-y） after focal cerebral ischemia in rats. Methods Totally 48 male Sprague-Dawley （SD） rats were randomly assigned into six groups （n=8 in each group）： animals in group ischemia/reperfusion （I/R） only received 120-minute transient middle cerebral artery occlusion （tMCAO）; animals in group I/R ＋FA were administered FA （10 mg/kg） by caudal vein just after 120-minute tMCAO; animals in group I/R ＋FA＋GW9662 were administered GW9662 （a PPAR-Y inhibitor, 1 mg/kg） intraperitoneally 30 minutes before cerebral ischemia onset and FA （10 mg/kg） by caudal vein just after 120-minute tMCAO; animals in group I/R ＋GW9662 were administered GW9662 （1 mg/kg） intraperitoneally 30 minutes before cerebral ischemia onset; animals in group I/R ＋DMSO were administered 3% DMSO （vehicle of GW9662, 1 ml/kg） intraperitoneally 30 minutes before cerebral ischemia onset; animals in sham group experienced the identical surgery apart from the insertion of the nylon filament. The neurologic deficit score （NDS） were performed at 72 hours after reperfusion, and then mean brain infarct volume percentage （MBIVP） was determined with 2,3,5-triphenyltetrazolium chloride （TTC） 10 g/L staining. Results NDS was significantly increased in group I/R＋FA （12.0 （10.0-15.0））, group I/R＋FA＋GW9662 （10.0 （8.0-12.0））, and in group I/R＋FA＋DMSO （12.0 （9.0-14.0）） at 72 hours after reperfusion compared with those in group I/R （7.5 （6.0-10.0））. NDS was conspicuously different between group I/R＋FA （12.0 （10.0-15.0）） and group I/R＋FA＋GW9662 （10.0 （8.0-12.0））. MBIVP in group I/R （（45.82±8.83）%） was significantly greater than that in group I/R＋FA （（23.52±9.90）%）, group I/R＋FA＋GW9662 （（33.17±7.15）%）; MBIVP in group I/R＋FA （（23.52±9.90）%） was significantly smaller than that in group I/R＋FA＋GW9662 （（33.17±7.15）%）. Conclusions FA confers the neuroprotective effect on tMCAO in rats and the selective PPAR-Y antagonist GW9662 attenuates the effect of FA. FA could promote a neuroprotective effect by, or in part, activation of PPAR-y after focal cerebral ischemia in rats.
基金supported by a grant(A121911 and HI14C2348)of the Korean Health Technology R&D Project,Ministry of Health&WelfareNational Research Foundation of Korea(NRF)(2011-0012728 and 2014R1A2A1A11051520)
文摘MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington＇s disease mouse models and patients is decreased. However, the effects of microRNA-124 on the progression of Huntington＇s disease have not been reported. Results from this study showed that microRNA-124 increased the latency to fall for each R6/2 Hunting- ton＇s disease transgenic mouse in the rotarod test. 5-Bromo-2＇-deoxyuridine （BrdU） staining of the striatum shows an increase in neurogenesis. In addition, brain-derived neurotrophic factor and peroxisome proliferator-activated receptor gamma coactivator 1-alpha protein levels in the striatum were increased and SRY-related HMG box transcription factor 9 protein level was de- creased. These findings suggest that microRNA-124 slows down the progression of Huntington＇s disease possibly through its important role in neuronal differentiation and survival.
文摘Accumulating evidence suggests that the Thl immune .response induced by various antigens such as oxidized low density lipoprotein （ox-LDL） and heat shock proteins （HSPs） play a key role in the process of atherosclerosis.1Dendritic cells （DCs） are the most potent antigen-presenting cells （APCs） in the body with the unique ability to initiate a primary immune response to certain antigens by the activation of ＂naive＂ T cells.2 The maturation of DC with the upregulation of costimulatory molecules such as CD83, CD40, CD86, and major histocompatibility complex （MHC） class molecules such as human leukocyte antigen （HLA）-DR, is required for DC to activate T cells. Pathologic studies have shown that immature DCs are present in normal arterial while abundant mature DCs clustered with T cells could be visualized in atherogenic vessels suggesting that DC 3 maturation is linked to the progression of atherosclerosls. Peroxisome proliferator-activated receptors （PPARs） a, one member of the family of PPARs, was found to have favorable effects on slowing the progression of atherosclerosis and reducing the risk of coronary heart disease in high-risk patients independent from their metabolism effects.4＇5 Furthermore, PPAR-α is also expressed on monocytes and monocyte-derived DCs.6 The effects of PPAR-α on DCs maturation and immune function remain unknown now, we therefore observed the effects of fenofibrate, a PPAR-α agonist, on the maturation and immune function of oxidized LDL-treated DCs in this study.
文摘Objective： To explore the molecular mechanism of puerarin （Pue） in improving insulin resistance through observing its effect on the insulin resistance of 3T3-Li lipocyte induced by free fatty acid （FFA）. Methods： 3T3-L1 preadipocyte was induced by a culture solution containing insulin, isobutyo-menthyl-xanthine, and dexamethasone to mature lipocyte, and it was divided into six groups： the control group （normal cells）, the model group （untreated model cells）, and the four drug treatment group exposed to dimethyl biguanide （Met group）, high- dose pueradn （PueH group）, low-dose puerarin （PueL group）, and propylene glycol （PG group）, respectively. Mature lipocytes in various groups, except those in the normal group, were established into insulin resistance model by FFA induction and treated respectively with corresponding drugs. Peroxisome proliferator-activated receptor- γ （PPAR- γ） mRNA expressions at the fourth, sixth, and eighth day were observed using reverse transcription polymerase chain reaction （RT-PCR）; glucose transportation in various groups were observed by 2-deoxy-[3H]-D-glucose intake method; mRNA expression of Cbl binding protein （CAP） was determined by RT-PCR; and glucose transporter-4 （Glut-4） transposition was detected by immune-fluorescence method. Results： PPAR- γmRNA expression increased gradually, and it showed lower levels at the fourth, sixth, and eighth day in all treatment groups than that in the model group. Glucose transportation determination showed that the transportation in the model group was 2.23 ± 0.63, significantly lower than that in the normal group 5.05 ± 0.66 （P〈0.01）; as compared with the model group, they were significantly higher in the PueH and the PueL groups. In addition, the CAP mRNA expression and membranous distribution of Glut-4 were higher in the two Pue treated groups than those in the model group, respectively. Conclusion： Pue could markedly improve the insulin resistance of 3T3-L1 lipocyte, which is realized possibly by way of inactivating CAP path, promoting Glut-4 transposition to cell membrane to increase the transportation of glucose.
