The aim of this study was to investigate the effect of different concentrations of sporamin on the differentiation and proliferation of 3T3-LI preadipocytes, providing the theoretical basis for the development of food...The aim of this study was to investigate the effect of different concentrations of sporamin on the differentiation and proliferation of 3T3-LI preadipocytes, providing the theoretical basis for the development of food to treat obesity and diabetes, The isolation and purification of sporamin from sweet potato species 55-2 were performed by ammonium sulphate precipitation in combination with ion-exchange and gel filtration chromatography. With berberine as a positive control, different concentrations ofsporamin （0.000, 0.125, 0.025, 0.250, 0.500, and 1.000 mg·mL^-1 were used to treat 3T3-L1 preadipocytes. Intracellular fat accumulation and the degree of adipogenesis were quantified using Oil Red O staining and colorimetry, Preadipocytes differentiation was measured by 3（4,5-dimethylthiazolyl-2-yl）-2,5-diphenyltetrazolium bromide （MTT） spectrophotometric assay. Two sporamin proteins, which were separated into sporamin A （31 kD） and sporamin B （22 kD）, could be purified by ion-exchange and gel filtration chromatography. After being treated by different concentrations of sporamin, the differentiation of 3T3-L1 preadipocytes was significantly inhibited, compared with the positive control. When the sporamin solution concentration was 0.500 mg mL-1, the accumulation of lipid droplets within the cells was significantly decreased and the optical density （OD） value of the solution from destained Oil Red O reached to 0.35, which was the lowest value （P〈 0.05）. The proliferation of 3T3-L1 preadipocytes was significantly inhibited by treating at higher sporamin concentrations. In addition, the inhibitory effect was more obvious with the prolonged treatment time （P〈 0.05）. The differentiation and proliferation of 3T3-L1 preadipocytes could be inhibited significantly by the addition of higher concentration sporamin. It was, therefore, suggested that the sporamin was potentially effective for weight loss.展开更多
Objective： To explore the effects of thiazolidinediones （TZDs） pioglitazone on proliferation and differentiation of human preadipocytes. Methods：Omental adipose tissue biopsies were obtained from 15 patients who w...Objective： To explore the effects of thiazolidinediones （TZDs） pioglitazone on proliferation and differentiation of human preadipocytes. Methods：Omental adipose tissue biopsies were obtained from 15 patients who were undergoing elective open-abdominal surgery. The primary culture and differentiated induction of human preadipocytes were performed, and the human preadipo-cytes were treated with pioglitazone at different concentrations at proper moments. Dynamic morphological changes of the human preadipocytes were observed, and their proliferation and differentiation were assessed with Colorimetric MTT Assay and Oil Red O Staining. Results：After 24 hours and 72 hours with pioglitazone, 0.1 μmol/L （μmol/ml） pioglitazone increased the MTT values of the human preadipocytes by 25.3% and 34.8%,respectively（P 〈 0.05）, while 1 μmol/L pioglitazone by 27.4% and 26.6%（P 〈 0.05）, compared with the control group without pioglitazone. The human preadipocytes with pioglitazone cumulated more adipose in the endochylema than those without pioglitazone obviously. 0.1 μmol/L pioglitazone increased the differentiation degree of the human preadipocytes differentiated for 8-10 days by 44.81% and 1 μmol/L pioglitazone by 53.76%（P 〈 0.05）. Conclusion：Thi- azolidinediones pioglitazone may significantly promote the proliferation and differentiation of the human omental preadipocytes.展开更多
Conjugated linoleic acids （CLAs） are a generic term for linoleic acid isomers and have a variety of biological functions. After rat preadi- pocytes were incubated in CLAs-supplemented media, their proliferation and ...Conjugated linoleic acids （CLAs） are a generic term for linoleic acid isomers and have a variety of biological functions. After rat preadi- pocytes were incubated in CLAs-supplemented media, their proliferation and differentiation were observed by the cell count and the oil red O stai- ning. The results showed that the CLAs at different concentrations inhibited proliferation of the rat preadipocytes in a time- and dose-dependent manner. And the CLAs greatly decreased intracellular lipid content in mature adipocytes. Moreover, lipogenesis was inhibited by the CLAs in a dose-dependent manner. Therefore, the CLAs inhibit the lipogenesis by reducing the number of preadipocytes and decreasing the intracellular lipid展开更多
The effects of ghrelin on the proliferation and differentiation of 3T3-L1 preadipocytes and the possible mechanisms were investigated in this study. 3T3-L1 preadipocytes were cultured in vitro and treated with differe...The effects of ghrelin on the proliferation and differentiation of 3T3-L1 preadipocytes and the possible mechanisms were investigated in this study. 3T3-L1 preadipocytes were cultured in vitro and treated with different concentrations of ghrelin. Proliferation of 3T3-L1 preadipocytes was evaluated by MTT method and mRNA levels of c-myc and thymidine kinase were detected by RT-PCR. Morphological changes of 3T3-L1 preadipocytes were observed and cell differentiation was measured by oil red O staining. The mRNA levels of peroxisome proliferator-activated receptor γ （PPARγ） and CAAT/enhancer binding protein （C/EBPa） in the cells at different differentiation stages were detected by RT-PCR. The results showed that ghrelin at concentrations of 10^-7 to 10^-15 mol/L could significantly promote preadipocyte proliferation （P〈0.05）, with the most pronounced effect observed at 10^-11 mol/L （P〈0.01）. Treatment of 3T3-L1 preadipocytes with ghrelin significantly increased the mRNA levels of c-myc and thymidine kinase （P〈0.01）. Morphological findings demonstrated that the great amount of lipid droplets appeared in the 3T3-L1 preadipocytes treated with ghrelin. Ghrelin could morphologically induce the differentiation of 3T3-L1 preadipocytes into mature adipocytes. Ghrelin significantly increased the mRNA levels of PPAR7 and C/EBPα during the differentiation, when compared with control group （P〈0.05）. The mRNA levels of PPARγ and C/EBPα were obviously up-regulated with the differentiation of preadipocytes after the treatment of ghrelin. There were significant difference in the mRNA levels of PPARγ and C/EBPu on day 2 and day 8 of the differentiation of 3T3-L1 preadipocytes （P〈0.01）. In conclusion, ghrelin could promote the proliferation and differentiation of 3T3-L1 preadipocytes by increasing the mRNA levels of PPARγ and C/EBPα and therefore enhance the sensitivity of adipocytes against insulin.展开更多
[Objective] The research aimed to discuss the effects of rosiglitazone and serum on the expressions of PPARα and PPARγ genes in the induced differentiation process of pig preadipocyte.[Method] The pig preadipocyte w...[Objective] The research aimed to discuss the effects of rosiglitazone and serum on the expressions of PPARα and PPARγ genes in the induced differentiation process of pig preadipocyte.[Method] The pig preadipocyte was separated by using the collagenase digestion method.Three kinds of different differentiation culture solutions were used to induce the differentiation of pig preadipocyte.The oil red O staining extraction method was used to contrast the influences of different differentiation culture solutions on the variation of cellular fat content in the differentiation process.Moreover,the variation trends of PPARα and PPARγ expressions in the cellular differentiation process in the different differentiation culture solutions were detected by the real-time quantification PCR.[Result] The cellular fat accumulation was the fastest in MII which contained rosiglitazone and was the slowest in MI which didn＇t contain rosiglitazone.Rosiglitazone could significantly increase the expression of PPARγ gene（P0.01）,but had the certain inhibition effect on the expression of PPARα gene,which wasn＇t significant.The serum had the extremely significant up-regulation effect on the expression of PPARγ gene（P0.01）,but had the extremely significant down-regulation effect on the expression of PPARα gene（P0.01）.[Conclusion] Rosiglitazone could greatly promote the expression of PPARγ gene,which increased the cellular fat deposition.Maybe the activator of PPARγ gene existed in the serum,and the inhibitor of PPARα gene existed simultaneously.展开更多
Objective： To investigate the effect of the calcium channel blocker verapamil on adipocyte differentiation and its mechanism of action. Methods： Preadipocytes from 3T3-L1 strain mouse embryos were cultured and diffe...Objective： To investigate the effect of the calcium channel blocker verapamil on adipocyte differentiation and its mechanism of action. Methods： Preadipocytes from 3T3-L1 strain mouse embryos were cultured and differentiated into matured adipocytes in vitro. Verapamil was added to the culture medium in the concentration of 30 μmol/L on Day 0. Cell differentiation was determined by Oil Red O staining and marker gene mRNA expression was evaluated and compared by RT-PCR. The fluo-3/AM probe and laser scanning confocal microscopy were used to measure intracetlular calcium concentrations. Results： （1）The differentiation rate of 3T3-L1 preadipocytes exposed to verapamil was lower than that of untreated cells. （2）Verapamil promoted the retention of pref-1 gene expression. Lipoprotein lipase expression in the verapamil group was significantly lower than that in the control group on Day 4, Day 6 and Day 8 （P 〈 0.05） and resistin expression was significantly lower than that in the control group on Day 6, Day 8 and Day 10 （P 〈 0.05）. Fatty acid synthase expression in the verapamil group was significantly lower than that in the control group from Day 2 （P 〈 0.05）. （3） Intracellular concentrations of calcium [Ca^2＋]i in the verapamil group were significantly decreased compared with those in the control group on Day 2, Day 4 and Day 6 （P 〈 0.05）, while there was no obvious difference between the two groups on Day 0 （P 〉 0.05）. Conclusion： In 3T3-L1 preadipocytes verapamil significantly reduced adipocyte differentiation, down-regulated the mRNA expression of three marker genes for adipocytes differentiation, and prolonged the mRNA expression of an inhibitor of differentiation. The inhibitory effect of verapamil on differentiation may involve its role as a blocker of calcium influx in adipocytes.展开更多
Background: Preadipocyte differentiation plays a critical role in subcutaneous fat deposition in pigs.However,the roles of different RNAs,such as messenger RNAs(mRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(c...Background: Preadipocyte differentiation plays a critical role in subcutaneous fat deposition in pigs.However,the roles of different RNAs,such as messenger RNAs(mRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs) in the differentiation process of subcutaneous preadipocytes,are still largely unclear.In the present study,a transcriptome analysis,including the analysis of mRNAs,lncRNAs,and circRNAs,during different differentiation stages,namely,day 0(D0),day 2(D2),day 4(D4),and day 8(D8),of subcutaneous preadipocytes from Chinese Erhualian pigs was performed.Results: A total of 1554,470,1344,1777,and 676 differentially expressed(DE) mRNAs,112,58,95,136,and 93 DE lncRNAs,and 902,787,710,932,and 850 DE circRNAs were identified between D2 and D0,between D4 and D2,between D8 and D4,between D4 and D0,and between D8 and D0,respectively.Furthermore,functional enrichment analysis showed that the common DE mRNAs during the entire differentiation process were mainly involved in lipid metabolic and cell differentiation processes.Additionally,co-expression network analysis identified the potential lncRNAs related to adipogenesis,e.g.,MSTRG.131380 and MSTRG.62128.Conclusions: Our study provides new insights of the expression changes of RNAs during adipogenic differentiation,which might contribute to the phenotype of subcutaneous adipogenesis.These results greatly improve our understanding of the molecular mechanisms regulating subcutaneous fat deposition in pigs.展开更多
The present study investigates the molecular details of how arsenic trioxide inhibits preadipocyte differentiation and examines the role of Akt/PKB in regulation of differentiation and apoptosis. Continual exposure of...The present study investigates the molecular details of how arsenic trioxide inhibits preadipocyte differentiation and examines the role of Akt/PKB in regulation of differentiation and apoptosis. Continual exposure of arsenic trioxide, at the clinic achievable dosage that does not induce apoptosis, suppressed 3T3-L1 cell differentiation into fat cells by inhibiting the expression of PPARγ and C/EBPα and disrupting the interaction between PPARγ and RXRα, which determines the programming of the adipogenic genes. Interestingly, if we treated the cells for 12 or 24 h and then withdrew arsenic trioxide, the cells were able to differentiate to the comparable levels of untreated cells as assayed by the activity of GAPDH, the biochemical marker of preadipocyte differentiation. Long term treatment blocked the differentiation and the activity of GAPDH could not recover to the comparable levels of untreated cells. Continual exposure of arsenic trioxide caused accumulation in G2/M phase and the accumulation of p21. We found that arsenic trioxide induced the expression and the phosphorylation of Akt/PKB and it inhibited the interaction between Akt/PKB and PPARγ . Akt/PKB inhibitor appears to block the arsenic trioxide suppression of differentiation. Our results suggested that Akt/PKB may play a role in suppression of apoptosis and negatively regulate preadipocyte differentiation.展开更多
Obesity presents a serious threat to human health and broiler performance.The expansion of adipose tissue is mainly regulated by the differentiation of preadipocytes.The differentiation of preadipocytes is a complex b...Obesity presents a serious threat to human health and broiler performance.The expansion of adipose tissue is mainly regulated by the differentiation of preadipocytes.The differentiation of preadipocytes is a complex biological process regulated by a variety of transcription factors and signaling pathways.Previous studies have shown that the transcription factor HMG-box protein 1(HBP1)can regulate the differentiation of mouse 3T3-L1 preadipocytes by activating the Wnt/β-catenin signaling pathway.However,it is unclear whether HBP1 involved in chicken preadipocyte differentiation and which signaling pathways it regulates.The aim of the current study was to explore the biological function and molecular regulatory mechanism of HBP1 in the differentiation of chicken preadipocytes.The expression patterns of chicken HBP1 in abdominal adipose tissue and during preadipocyte differentiation were analyzed by RT-qPCR and Western blot.The preadipocyte stably overexpressing HBP1 or knockout HBP1 and their control cell line were used to analyze the effect of HBP1 on preadipocyte differentiation by oil red O staining,RT-qPCR and Western blot.Cignal 45-Pathway Reporter Array was used to screen the signal pathways that HBP1 regulates in the differentiation of chicken preadipocytes.Chemical inhibitor and siRNA for signal transducer and activator of transcription 3(STAT3)were used to analyze the effect of STAT3 on preadipocyte differentiation.The preadipocyte stably overexpressing HBP1 was transfected by the siRNA of STAT3 or treated with a chemical inhibitor of STAT3 for the rescue experiment.The results of gene expression analysis showed that the expression of HBP1 was related to abdominal fat deposition and preadipocyte differentiation in chickens.The results of function gain and loss experiments indicated that overexpression/knockout of HBP1 in chicken preadipocytes could inhibit/promote(P<0.05)lipid droplet deposition and the expression of adipogenesis-related genes.Mechanismlly,HBP1 activates(P<0.05)the signal transducer and activator of transcription 3(STAT3)signaling pathway by targeting janus kinase 2(JAK2)transcription.The results of functional rescue experiments indicated that STAT3 signaling mediated the regulation of HBP1 on chicken preadipocyte differentiation.In conclusion,HBP1 inhibits chicken preadipocyte differentiation by activating the STAT3 signaling pathway via directly enhancing JAK2 expression.Our findings provided new insights for further analysis of the molecular genetic basis of chicken adipose tissue growth and development.展开更多
Background: Despite the popularity of autologous fat transfer applications, high resorption rates, and consequential volume loss, have been reported. Viable adipocyte content has been defined as a key determinant of f...Background: Despite the popularity of autologous fat transfer applications, high resorption rates, and consequential volume loss, have been reported. Viable adipocyte content has been defined as a key determinant of fat transfer longevity. Moreover, traces of blood, free oil fat and fibrotic tissue accelerate adipocyte degradation. Objective: To compare the effectiveness of a 1470 nm, radial emitting laser-assisted liposection device to a mechanical liposection device in maintaining adipocyte viability in fat tissue harvests. Methods: Bilateral subcutaneous adipose tissue samples were harvested from ten female patients. Fat was harvested from one side using the LipoLife laser-assisted liposuction device and from the other side with a Byron mechanical aspirator. Samples were visually analyzed and blood:fat ratios and cell viability were determined. Results: Laser-harvested samples separated into two distinct phases, with a negligible blood phase at the bottom (1.1%) and a significant adipose phase at the top (98.9%), containing small, uniform-sized cells, of which 95.7% ± 2.7% proved viable. Mechanically harvested samples separated into blood (18%), adipose (60%) and lipid (22%) phases. The adipose phase contained significant amounts of connective tissue, large adipose tissue fragments, large oil droplets and a mean 79.7% ± 18.3% viable adipocytes. Conclusions: Laser liposuctioning was superior to mechanical liposuctioning, providing both higher cell viability and enhanced sample quality. The 1470 nm diode laser bears the potential of improving long-term clinical outcomes of fat transfer procedures. Improved purity of the harvested sample and heightened preadipocyte content are projected to provide for extended graft longevity.展开更多
Objective To study the effects of emodin on proliferation and differentiation of 3T3 L1 preadipocyte and the possible mechanism Methods Cell proliferation was determined by MTT spectrophotometry, cell differentiat...Objective To study the effects of emodin on proliferation and differentiation of 3T3 L1 preadipocyte and the possible mechanism Methods Cell proliferation was determined by MTT spectrophotometry, cell differentiation was determined by Oil Red O staining, and fatty acid synthase (FAS) activity was determined by spectrophotometry Results Emodin promoted proliferation of 3T3 L1 preadipocyte at low concentration and inhibited the proliferation at high concentration in a dose related manner In contrast, it inhibited cell differentiation into adipocyte at low concentration in a dose related manner In vitro emodin inhibited the activity of FAS in a dose related manner Conclusions The effects of emodin on 3T3 L1 cell's proliferation and differentiation are dose dependent Emodin inhibits the activity of FAS Our results suggest that emodin should have a potential to serve as a fat reducing drug展开更多
White adipose tissue(WAT)is a highly plastic organ that plays a central role in regulating whole-body energy metabolism.Adipose stem and progenitor cells(ASPCs)are essential components of the stromal vascular fraction...White adipose tissue(WAT)is a highly plastic organ that plays a central role in regulating whole-body energy metabolism.Adipose stem and progenitor cells(ASPCs)are essential components of the stromal vascular fraction(SVF)of adipose tissue.They give rise to mature adipocytes and play a critical role in maintaining adipose tissue function.However,the molecular heterogeneity and functional diversity of ASPCs are still poorly understood.Recently,single-cell RNA sequencing(scRNA-seq)analysis has identified distinct subtypes of ASPCs in murine and human adipose tissues,providing new insights into the cellular complexity of ASPCs among multiple fat depots.This review summarizes the current knowledge on ASPC populations,including their markers,functions,and regulatory mechanisms.Targeting one or several of these cell populations may ameliorate metabolic disorders by promoting adaptive hyperplastic adipose growth.展开更多
Imipramine （IM） has been widely used clinically for the treatment of mental disorders. Its actions on tissues or organs other than the nervous system also need to be understood for its proper clinical use. In this s...Imipramine （IM） has been widely used clinically for the treatment of mental disorders. Its actions on tissues or organs other than the nervous system also need to be understood for its proper clinical use. In this study, the effects of IM on adipogenic differentiation in both 3T3-L1 preadipocytes and mouse marrow stromal cells （MSCs） were investigated. The results showed that fewer adipocytic cells were developed from 3T3-L1 preadipocytes in the presence of 0.001 to 1 μmol/L of IM as compared to control. Similar inhibitory effect was also observed in mouse MSCs. The decrease in the formation of adipocytes was accompanied with significant down-regulation at mRNA expression of the early adipogenic transcription factor, peroxisome proliferator-activated receptor γ2 （PPARγ2）. Western blot analysis further revealed that the protein expression of PPARγ2 was reduced markedly in ceils treated with IM at concentrations of 0.01, 0.1 and 1 μmol/L, suggesting that the suppression on PPAR72 was involved in IM＇s inhibition on MSCs adipogenesis. Moreover, IM at the above concentrations could stimulate the mRNA expression of β2-adrenergic receptor （AR） and β3-AR, which implicated that the effect of IM on adipogenic differentiation was partially mediated by β-ARs. Our results demonstrated for the first time that the conventional antidepressive imipramine exerts accompanied inhibitory effect on adipocyte formation, which may have possible clinical implications.展开更多
Background CCAAT/enhancer-binding protein β（C/EBPβ） is required for mitotic clonal expansion （MCE） during adipogenesis. It is still unclear how C/EBPp regulates MCE in the earlier differentiation programs of 3T3...Background CCAAT/enhancer-binding protein β（C/EBPβ） is required for mitotic clonal expansion （MCE） during adipogenesis. It is still unclear how C/EBPp regulates MCE in the earlier differentiation programs of 3T3-L1 preadipocytes. The purpose of this paper was to understand why C/EBPβ is required for preadipocyte proliferation, and identify new target genes of C/EBPP with chromatin immunoprecipitation （ChlP）-on-chip. Methods Postconfluent growth-arrested 3T3-L1 preadipocytes were induced to differentiation using a standard differentiation protocol. Chip was performed at 20 hours after induction with specific anti-C/EBPβ antibodies. The precipitated DNA was amplified, labeled and hybridized with a mouse promoter microarray. Compared with the control in which the ChIP experiment was performed with non-specific antibody, only the genes with a signal increasing more than 2 fold were considered as candidate genes.Results A total of 110 candidate genes were identified. BTG3 associated nuclear protein （SMAR1, Banp） and tripartite motif-containing 35 （Hls5, trim35） were two target genes among the 110 candidate genes which are involved in cell cycle regulation; the binding of C/EBP3 to the promoter of banp and trim35 was verified by ChlP-PCR. Conclusion C/EBPβ may regulate preadipocyte proliferation through activation of banp and trim35.展开更多
Dextran-hyaluronate （Dex-HA） based supermacroporous cryogel scaffolds for soft tissue engineering were prepared by free radical cryo-copolymerization of aqueous solutions containing the dextran methacrylate （Dex-MA...Dextran-hyaluronate （Dex-HA） based supermacroporous cryogel scaffolds for soft tissue engineering were prepared by free radical cryo-copolymerization of aqueous solutions containing the dextran methacrylate （Dex-MA） and hyaluronate methacrylate （HA-MA） at various macromonomer concentrations under the freezing condition. It was observed that the suitable total concen- tration of macromonomers for the preparation of Dex-HA cryogel scaffold with satisfied properties was 5% （w/w） at the HA-MA concentration of 1% （w/v）, which was then used to produce the test scaffold. The obtained cryogel scaffold with 5% （w/w） macromonomer solution had high water permeability （5.1 × 10 ^-2m2） and high porosity （92.4%）. The pore diameter examined by scanning electron microscopy （SEM） was in a broad range of 50-135 um with the mean pore diameter of 91 um. Furthermore, the cryogel scaffold also had good elastic nature with the elastic modulus of 17.47±1.44 kPa. The culture of 3T3-L1 preadipocyte within the scaffold was investigated and observed by SEM. Cells clustered on the pore walls and grew inside the scaffold indicating the Dex-HA cryogel scaffold could be a promising porous biomaterial for applications in tissue engineering.展开更多
An in vitro cultured rat perirenal preadipocyte (PA) was established as a model system to investigate the role of the intracellular pH (pHi) and of the Na+/H+ exchanger during PA proliferation and differentiation. pH ...An in vitro cultured rat perirenal preadipocyte (PA) was established as a model system to investigate the role of the intracellular pH (pHi) and of the Na+/H+ exchanger during PA proliferation and differentiation. pH sensitive probe, 2' ,7'-bis-(2-carboxyethyl)-5(6)-carboxyfluorescein(BCECF) , was employed to measure the pHi of PA and to determine the Na+/H+ exchange activity. The results showed that there was Na+/H+ exchange activity in the plasma membrane of PA, FCS stimulated DNA synthesis measured by H-TdR incorporation, and the activation of Na + /H + exchanger resulted in pHi increase (nearly 0.2 pH unit) within 2 min. Ethyl-isopropyl-amiloride (EIPA) , a specific Na+/H+ exchange inhibitor, inhibited Na+/H+ exchange activity and DNA synthesis. In the absence of serum insulin did not stimulate DNA synthesis but did induce PA differentiation characterized by the appearance of adiposome in the cell and the enhancement of glycerol-3-phosphate dehydrogenase (G3 PDHase) activity. Meantime, insulin was also found to stimulate Na+/H+ exchange activity and pHi increase. EIPA inhibited Na+/H+ exchanger activation induced by insulin and also partially inhibited the enhancement of G3PDHase activity. These results demonstrated that the activation of Na+ /H+ exchange and the resulting pHi increase are the early events related to both proliferation and differentiation of PA.展开更多
Obesity is increasingly prevalent globally, searching for therapeutic agents acting on adipose tissue is of great importance. Equisetin(EQST), a meroterpenoid isolated from a marine sponge-derived fungus, has been rep...Obesity is increasingly prevalent globally, searching for therapeutic agents acting on adipose tissue is of great importance. Equisetin(EQST), a meroterpenoid isolated from a marine sponge-derived fungus, has been reported to display antibacterial and antiviral activities. Here, we revealed that EQST displayed anti-obesity effects acting on adipose tissue through inhibiting adipogenesis in vitro and attenuating HFD-induced obesity in mice, doing so without affecting food intake, blood pressure or heart rate.We demonstrated that EQST inhibited the enzyme activity of 11β-hydroxysteroid dehydrogenase type 1(11β-HSD1), a therapeutic target of obesity in adipose tissue. Anti-obesity properties of EQST were all offset by applying excessive 11β-HSD1’s substrates and 11β-HSD1 inhibition through knockdown in vitro or 11β-HSD1 knockout in vivo. In the 11β-HSD1 bypass model constructed by adding excess11β-HSD1 products, EQST’s anti-obesity effects disappeared. Furthermore, EQST directly bond to11β-HSD1 protein and presented remarkable better intensity on 11β-HSD1 inhibition and better efficacy on anti-obesity than known 11β-HSD1 inhibitor. Therefore, EQST can be developed into anti-obesity candidate compound, and this study may provide more clues for developing higher effective 11β-HSD1 inhibitors.展开更多
In mammals,a thermogenic mechanism exists that increases heat production and consumes energy.Recent work has shed light on the cellular and physiological mechanisms that control this thermogenic circuit.Thermogenicall...In mammals,a thermogenic mechanism exists that increases heat production and consumes energy.Recent work has shed light on the cellular and physiological mechanisms that control this thermogenic circuit.Thermogenically active adipocytes,namely brown and closely related beige adipocytes,differentiate from progenitor cells that commit to the thermogenic lineage but can arise from different cellular origins.Thermogenic differentiation shares some features with general adipogenesis,highlighting the critical role that common transcription factors may play in progenitors with divergent fates.However,thermogenic differentiation is also discrete from the common adipogenic program and,excitingly,cells with distinct origins possess thermogenic competency that allows them to differentiate into thermogenically active mature adipocytes.An understanding of this thermogenic differentiation program and the factors that can activate it has led to the development of assays that are able to measure thermogenic activity both indirectly and directly.By combining these assays with appropriate cell models,novel therapeutic approaches to combat obesity and its related metabolic disorders by enhancing the thermogenic circuit can be developed.展开更多
基金supported by the National 863 Program of China (2006AA10Z332)the Ear Marked Fund for Modern Agro-Industry Technology Research System, China
文摘The aim of this study was to investigate the effect of different concentrations of sporamin on the differentiation and proliferation of 3T3-LI preadipocytes, providing the theoretical basis for the development of food to treat obesity and diabetes, The isolation and purification of sporamin from sweet potato species 55-2 were performed by ammonium sulphate precipitation in combination with ion-exchange and gel filtration chromatography. With berberine as a positive control, different concentrations ofsporamin （0.000, 0.125, 0.025, 0.250, 0.500, and 1.000 mg·mL^-1 were used to treat 3T3-L1 preadipocytes. Intracellular fat accumulation and the degree of adipogenesis were quantified using Oil Red O staining and colorimetry, Preadipocytes differentiation was measured by 3（4,5-dimethylthiazolyl-2-yl）-2,5-diphenyltetrazolium bromide （MTT） spectrophotometric assay. Two sporamin proteins, which were separated into sporamin A （31 kD） and sporamin B （22 kD）, could be purified by ion-exchange and gel filtration chromatography. After being treated by different concentrations of sporamin, the differentiation of 3T3-L1 preadipocytes was significantly inhibited, compared with the positive control. When the sporamin solution concentration was 0.500 mg mL-1, the accumulation of lipid droplets within the cells was significantly decreased and the optical density （OD） value of the solution from destained Oil Red O reached to 0.35, which was the lowest value （P〈 0.05）. The proliferation of 3T3-L1 preadipocytes was significantly inhibited by treating at higher sporamin concentrations. In addition, the inhibitory effect was more obvious with the prolonged treatment time （P〈 0.05）. The differentiation and proliferation of 3T3-L1 preadipocytes could be inhibited significantly by the addition of higher concentration sporamin. It was, therefore, suggested that the sporamin was potentially effective for weight loss.
文摘Objective： To explore the effects of thiazolidinediones （TZDs） pioglitazone on proliferation and differentiation of human preadipocytes. Methods：Omental adipose tissue biopsies were obtained from 15 patients who were undergoing elective open-abdominal surgery. The primary culture and differentiated induction of human preadipocytes were performed, and the human preadipo-cytes were treated with pioglitazone at different concentrations at proper moments. Dynamic morphological changes of the human preadipocytes were observed, and their proliferation and differentiation were assessed with Colorimetric MTT Assay and Oil Red O Staining. Results：After 24 hours and 72 hours with pioglitazone, 0.1 μmol/L （μmol/ml） pioglitazone increased the MTT values of the human preadipocytes by 25.3% and 34.8%,respectively（P 〈 0.05）, while 1 μmol/L pioglitazone by 27.4% and 26.6%（P 〈 0.05）, compared with the control group without pioglitazone. The human preadipocytes with pioglitazone cumulated more adipose in the endochylema than those without pioglitazone obviously. 0.1 μmol/L pioglitazone increased the differentiation degree of the human preadipocytes differentiated for 8-10 days by 44.81% and 1 μmol/L pioglitazone by 53.76%（P 〈 0.05）. Conclusion：Thi- azolidinediones pioglitazone may significantly promote the proliferation and differentiation of the human omental preadipocytes.
基金funded by Scientific and Technological Research Project of Chongqing Municipal Education Commission (KJ080827)National Natural Science Foundation of China (30800843)the Key Disciplines of Zoology of chongqing, chongqing Normal University
文摘Conjugated linoleic acids （CLAs） are a generic term for linoleic acid isomers and have a variety of biological functions. After rat preadi- pocytes were incubated in CLAs-supplemented media, their proliferation and differentiation were observed by the cell count and the oil red O stai- ning. The results showed that the CLAs at different concentrations inhibited proliferation of the rat preadipocytes in a time- and dose-dependent manner. And the CLAs greatly decreased intracellular lipid content in mature adipocytes. Moreover, lipogenesis was inhibited by the CLAs in a dose-dependent manner. Therefore, the CLAs inhibit the lipogenesis by reducing the number of preadipocytes and decreasing the intracellular lipid
基金supported by a grant from the National Natural Sciences Foundation of China (No.30600213)
文摘The effects of ghrelin on the proliferation and differentiation of 3T3-L1 preadipocytes and the possible mechanisms were investigated in this study. 3T3-L1 preadipocytes were cultured in vitro and treated with different concentrations of ghrelin. Proliferation of 3T3-L1 preadipocytes was evaluated by MTT method and mRNA levels of c-myc and thymidine kinase were detected by RT-PCR. Morphological changes of 3T3-L1 preadipocytes were observed and cell differentiation was measured by oil red O staining. The mRNA levels of peroxisome proliferator-activated receptor γ （PPARγ） and CAAT/enhancer binding protein （C/EBPa） in the cells at different differentiation stages were detected by RT-PCR. The results showed that ghrelin at concentrations of 10^-7 to 10^-15 mol/L could significantly promote preadipocyte proliferation （P〈0.05）, with the most pronounced effect observed at 10^-11 mol/L （P〈0.01）. Treatment of 3T3-L1 preadipocytes with ghrelin significantly increased the mRNA levels of c-myc and thymidine kinase （P〈0.01）. Morphological findings demonstrated that the great amount of lipid droplets appeared in the 3T3-L1 preadipocytes treated with ghrelin. Ghrelin could morphologically induce the differentiation of 3T3-L1 preadipocytes into mature adipocytes. Ghrelin significantly increased the mRNA levels of PPAR7 and C/EBPα during the differentiation, when compared with control group （P〈0.05）. The mRNA levels of PPARγ and C/EBPα were obviously up-regulated with the differentiation of preadipocytes after the treatment of ghrelin. There were significant difference in the mRNA levels of PPARγ and C/EBPu on day 2 and day 8 of the differentiation of 3T3-L1 preadipocytes （P〈0.01）. In conclusion, ghrelin could promote the proliferation and differentiation of 3T3-L1 preadipocytes by increasing the mRNA levels of PPARγ and C/EBPα and therefore enhance the sensitivity of adipocytes against insulin.
基金Supported by Ministry of Science & Technology International Cooper-ation Project(2011DFB30340)the Earmarked Fund for China Agriculture Research System(CARS-36)the Project of Animal Breeding from Sichuan Bureau of Science & Technology(2006-YZGG-15)~~
文摘[Objective] The research aimed to discuss the effects of rosiglitazone and serum on the expressions of PPARα and PPARγ genes in the induced differentiation process of pig preadipocyte.[Method] The pig preadipocyte was separated by using the collagenase digestion method.Three kinds of different differentiation culture solutions were used to induce the differentiation of pig preadipocyte.The oil red O staining extraction method was used to contrast the influences of different differentiation culture solutions on the variation of cellular fat content in the differentiation process.Moreover,the variation trends of PPARα and PPARγ expressions in the cellular differentiation process in the different differentiation culture solutions were detected by the real-time quantification PCR.[Result] The cellular fat accumulation was the fastest in MII which contained rosiglitazone and was the slowest in MI which didn＇t contain rosiglitazone.Rosiglitazone could significantly increase the expression of PPARγ gene（P0.01）,but had the certain inhibition effect on the expression of PPARα gene,which wasn＇t significant.The serum had the extremely significant up-regulation effect on the expression of PPARγ gene（P0.01）,but had the extremely significant down-regulation effect on the expression of PPARα gene（P0.01）.[Conclusion] Rosiglitazone could greatly promote the expression of PPARγ gene,which increased the cellular fat deposition.Maybe the activator of PPARγ gene existed in the serum,and the inhibitor of PPARα gene existed simultaneously.
基金supported by grants from the National Natural Science Foundation of China (30371502)the Natural Science Foundation of Jiangsu Province (BK2001120)
文摘Objective： To investigate the effect of the calcium channel blocker verapamil on adipocyte differentiation and its mechanism of action. Methods： Preadipocytes from 3T3-L1 strain mouse embryos were cultured and differentiated into matured adipocytes in vitro. Verapamil was added to the culture medium in the concentration of 30 μmol/L on Day 0. Cell differentiation was determined by Oil Red O staining and marker gene mRNA expression was evaluated and compared by RT-PCR. The fluo-3/AM probe and laser scanning confocal microscopy were used to measure intracetlular calcium concentrations. Results： （1）The differentiation rate of 3T3-L1 preadipocytes exposed to verapamil was lower than that of untreated cells. （2）Verapamil promoted the retention of pref-1 gene expression. Lipoprotein lipase expression in the verapamil group was significantly lower than that in the control group on Day 4, Day 6 and Day 8 （P 〈 0.05） and resistin expression was significantly lower than that in the control group on Day 6, Day 8 and Day 10 （P 〈 0.05）. Fatty acid synthase expression in the verapamil group was significantly lower than that in the control group from Day 2 （P 〈 0.05）. （3） Intracellular concentrations of calcium [Ca^2＋]i in the verapamil group were significantly decreased compared with those in the control group on Day 2, Day 4 and Day 6 （P 〈 0.05）, while there was no obvious difference between the two groups on Day 0 （P 〉 0.05）. Conclusion： In 3T3-L1 preadipocytes verapamil significantly reduced adipocyte differentiation, down-regulated the mRNA expression of three marker genes for adipocytes differentiation, and prolonged the mRNA expression of an inhibitor of differentiation. The inhibitory effect of verapamil on differentiation may involve its role as a blocker of calcium influx in adipocytes.
基金supported by the National Transgenic Project of China(2018ZX0800928B)the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2015BAD03B01)the National Natural Science Foundation of China(31501930)
文摘Background: Preadipocyte differentiation plays a critical role in subcutaneous fat deposition in pigs.However,the roles of different RNAs,such as messenger RNAs(mRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs) in the differentiation process of subcutaneous preadipocytes,are still largely unclear.In the present study,a transcriptome analysis,including the analysis of mRNAs,lncRNAs,and circRNAs,during different differentiation stages,namely,day 0(D0),day 2(D2),day 4(D4),and day 8(D8),of subcutaneous preadipocytes from Chinese Erhualian pigs was performed.Results: A total of 1554,470,1344,1777,and 676 differentially expressed(DE) mRNAs,112,58,95,136,and 93 DE lncRNAs,and 902,787,710,932,and 850 DE circRNAs were identified between D2 and D0,between D4 and D2,between D8 and D4,between D4 and D0,and between D8 and D0,respectively.Furthermore,functional enrichment analysis showed that the common DE mRNAs during the entire differentiation process were mainly involved in lipid metabolic and cell differentiation processes.Additionally,co-expression network analysis identified the potential lncRNAs related to adipogenesis,e.g.,MSTRG.131380 and MSTRG.62128.Conclusions: Our study provides new insights of the expression changes of RNAs during adipogenic differentiation,which might contribute to the phenotype of subcutaneous adipogenesis.These results greatly improve our understanding of the molecular mechanisms regulating subcutaneous fat deposition in pigs.
基金This work is supported by grants from National Nature Science Foundation of China(No.30000083)Quan.CHEN's laboratory was supported by grants“Knowledge Innovation Key Project"(kscx2-sw-2010)of Chinese Academy of Sciences+1 种基金the National Basic Research Program of China(973 program project,No.2002CB5 13 100)National Fund for Outstanding Young Scholars from NSFC(30325013)awarded to Quan CHEN.
文摘The present study investigates the molecular details of how arsenic trioxide inhibits preadipocyte differentiation and examines the role of Akt/PKB in regulation of differentiation and apoptosis. Continual exposure of arsenic trioxide, at the clinic achievable dosage that does not induce apoptosis, suppressed 3T3-L1 cell differentiation into fat cells by inhibiting the expression of PPARγ and C/EBPα and disrupting the interaction between PPARγ and RXRα, which determines the programming of the adipogenic genes. Interestingly, if we treated the cells for 12 or 24 h and then withdrew arsenic trioxide, the cells were able to differentiate to the comparable levels of untreated cells as assayed by the activity of GAPDH, the biochemical marker of preadipocyte differentiation. Long term treatment blocked the differentiation and the activity of GAPDH could not recover to the comparable levels of untreated cells. Continual exposure of arsenic trioxide caused accumulation in G2/M phase and the accumulation of p21. We found that arsenic trioxide induced the expression and the phosphorylation of Akt/PKB and it inhibited the interaction between Akt/PKB and PPARγ . Akt/PKB inhibitor appears to block the arsenic trioxide suppression of differentiation. Our results suggested that Akt/PKB may play a role in suppression of apoptosis and negatively regulate preadipocyte differentiation.
基金supported by the China Agriculture Research System of MOF and MARA of China (CARS41)
文摘Obesity presents a serious threat to human health and broiler performance.The expansion of adipose tissue is mainly regulated by the differentiation of preadipocytes.The differentiation of preadipocytes is a complex biological process regulated by a variety of transcription factors and signaling pathways.Previous studies have shown that the transcription factor HMG-box protein 1(HBP1)can regulate the differentiation of mouse 3T3-L1 preadipocytes by activating the Wnt/β-catenin signaling pathway.However,it is unclear whether HBP1 involved in chicken preadipocyte differentiation and which signaling pathways it regulates.The aim of the current study was to explore the biological function and molecular regulatory mechanism of HBP1 in the differentiation of chicken preadipocytes.The expression patterns of chicken HBP1 in abdominal adipose tissue and during preadipocyte differentiation were analyzed by RT-qPCR and Western blot.The preadipocyte stably overexpressing HBP1 or knockout HBP1 and their control cell line were used to analyze the effect of HBP1 on preadipocyte differentiation by oil red O staining,RT-qPCR and Western blot.Cignal 45-Pathway Reporter Array was used to screen the signal pathways that HBP1 regulates in the differentiation of chicken preadipocytes.Chemical inhibitor and siRNA for signal transducer and activator of transcription 3(STAT3)were used to analyze the effect of STAT3 on preadipocyte differentiation.The preadipocyte stably overexpressing HBP1 was transfected by the siRNA of STAT3 or treated with a chemical inhibitor of STAT3 for the rescue experiment.The results of gene expression analysis showed that the expression of HBP1 was related to abdominal fat deposition and preadipocyte differentiation in chickens.The results of function gain and loss experiments indicated that overexpression/knockout of HBP1 in chicken preadipocytes could inhibit/promote(P<0.05)lipid droplet deposition and the expression of adipogenesis-related genes.Mechanismlly,HBP1 activates(P<0.05)the signal transducer and activator of transcription 3(STAT3)signaling pathway by targeting janus kinase 2(JAK2)transcription.The results of functional rescue experiments indicated that STAT3 signaling mediated the regulation of HBP1 on chicken preadipocyte differentiation.In conclusion,HBP1 inhibits chicken preadipocyte differentiation by activating the STAT3 signaling pathway via directly enhancing JAK2 expression.Our findings provided new insights for further analysis of the molecular genetic basis of chicken adipose tissue growth and development.
文摘Background: Despite the popularity of autologous fat transfer applications, high resorption rates, and consequential volume loss, have been reported. Viable adipocyte content has been defined as a key determinant of fat transfer longevity. Moreover, traces of blood, free oil fat and fibrotic tissue accelerate adipocyte degradation. Objective: To compare the effectiveness of a 1470 nm, radial emitting laser-assisted liposection device to a mechanical liposection device in maintaining adipocyte viability in fat tissue harvests. Methods: Bilateral subcutaneous adipose tissue samples were harvested from ten female patients. Fat was harvested from one side using the LipoLife laser-assisted liposuction device and from the other side with a Byron mechanical aspirator. Samples were visually analyzed and blood:fat ratios and cell viability were determined. Results: Laser-harvested samples separated into two distinct phases, with a negligible blood phase at the bottom (1.1%) and a significant adipose phase at the top (98.9%), containing small, uniform-sized cells, of which 95.7% ± 2.7% proved viable. Mechanically harvested samples separated into blood (18%), adipose (60%) and lipid (22%) phases. The adipose phase contained significant amounts of connective tissue, large adipose tissue fragments, large oil droplets and a mean 79.7% ± 18.3% viable adipocytes. Conclusions: Laser liposuctioning was superior to mechanical liposuctioning, providing both higher cell viability and enhanced sample quality. The 1470 nm diode laser bears the potential of improving long-term clinical outcomes of fat transfer procedures. Improved purity of the harvested sample and heightened preadipocyte content are projected to provide for extended graft longevity.
文摘Objective To study the effects of emodin on proliferation and differentiation of 3T3 L1 preadipocyte and the possible mechanism Methods Cell proliferation was determined by MTT spectrophotometry, cell differentiation was determined by Oil Red O staining, and fatty acid synthase (FAS) activity was determined by spectrophotometry Results Emodin promoted proliferation of 3T3 L1 preadipocyte at low concentration and inhibited the proliferation at high concentration in a dose related manner In contrast, it inhibited cell differentiation into adipocyte at low concentration in a dose related manner In vitro emodin inhibited the activity of FAS in a dose related manner Conclusions The effects of emodin on 3T3 L1 cell's proliferation and differentiation are dose dependent Emodin inhibits the activity of FAS Our results suggest that emodin should have a potential to serve as a fat reducing drug
基金supported by the National Key R&D Program of China (2020YFA0803604)the National Natural Science Foundation of China (81770868, 91742103, 82130024 and 82170866)+1 种基金the Science and Technology Innovation Program of Hunan Province (2020RC4009)the Project of Innovation-Driven Plan of Central South University (2020CX015)
文摘White adipose tissue(WAT)is a highly plastic organ that plays a central role in regulating whole-body energy metabolism.Adipose stem and progenitor cells(ASPCs)are essential components of the stromal vascular fraction(SVF)of adipose tissue.They give rise to mature adipocytes and play a critical role in maintaining adipose tissue function.However,the molecular heterogeneity and functional diversity of ASPCs are still poorly understood.Recently,single-cell RNA sequencing(scRNA-seq)analysis has identified distinct subtypes of ASPCs in murine and human adipose tissues,providing new insights into the cellular complexity of ASPCs among multiple fat depots.This review summarizes the current knowledge on ASPC populations,including their markers,functions,and regulatory mechanisms.Targeting one or several of these cell populations may ameliorate metabolic disorders by promoting adaptive hyperplastic adipose growth.
基金supported by a grant from UGC Area of Excellence project "Chinese Medicine Research and Further Development"(No.AoE/B-10/01)the Shenzhen Key Laboratory Funding Scheme of Shenzhen Municipal Government, Shenzhen Double Hundred Project
文摘Imipramine （IM） has been widely used clinically for the treatment of mental disorders. Its actions on tissues or organs other than the nervous system also need to be understood for its proper clinical use. In this study, the effects of IM on adipogenic differentiation in both 3T3-L1 preadipocytes and mouse marrow stromal cells （MSCs） were investigated. The results showed that fewer adipocytic cells were developed from 3T3-L1 preadipocytes in the presence of 0.001 to 1 μmol/L of IM as compared to control. Similar inhibitory effect was also observed in mouse MSCs. The decrease in the formation of adipocytes was accompanied with significant down-regulation at mRNA expression of the early adipogenic transcription factor, peroxisome proliferator-activated receptor γ2 （PPARγ2）. Western blot analysis further revealed that the protein expression of PPARγ2 was reduced markedly in ceils treated with IM at concentrations of 0.01, 0.1 and 1 μmol/L, suggesting that the suppression on PPAR72 was involved in IM＇s inhibition on MSCs adipogenesis. Moreover, IM at the above concentrations could stimulate the mRNA expression of β2-adrenergic receptor （AR） and β3-AR, which implicated that the effect of IM on adipogenic differentiation was partially mediated by β-ARs. Our results demonstrated for the first time that the conventional antidepressive imipramine exerts accompanied inhibitory effect on adipocyte formation, which may have possible clinical implications.
基金This work was supported by the National Natural Science Foundation of China （No. 30700403）.
文摘Background CCAAT/enhancer-binding protein β（C/EBPβ） is required for mitotic clonal expansion （MCE） during adipogenesis. It is still unclear how C/EBPp regulates MCE in the earlier differentiation programs of 3T3-L1 preadipocytes. The purpose of this paper was to understand why C/EBPβ is required for preadipocyte proliferation, and identify new target genes of C/EBPP with chromatin immunoprecipitation （ChlP）-on-chip. Methods Postconfluent growth-arrested 3T3-L1 preadipocytes were induced to differentiation using a standard differentiation protocol. Chip was performed at 20 hours after induction with specific anti-C/EBPβ antibodies. The precipitated DNA was amplified, labeled and hybridized with a mouse promoter microarray. Compared with the control in which the ChIP experiment was performed with non-specific antibody, only the genes with a signal increasing more than 2 fold were considered as candidate genes.Results A total of 110 candidate genes were identified. BTG3 associated nuclear protein （SMAR1, Banp） and tripartite motif-containing 35 （Hls5, trim35） were two target genes among the 110 candidate genes which are involved in cell cycle regulation; the binding of C/EBP3 to the promoter of banp and trim35 was verified by ChlP-PCR. Conclusion C/EBPβ may regulate preadipocyte proliferation through activation of banp and trim35.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （Grant Nos. 20876145, 21036005）, the Science and Technology Cooperation Project between China-Europe Country＇s Governments from the Ministry of Science and Technology of China （No. 1017） and the Zhejiang Provincial Natural Science Foundation of China （No. Y4080326）.
文摘Dextran-hyaluronate （Dex-HA） based supermacroporous cryogel scaffolds for soft tissue engineering were prepared by free radical cryo-copolymerization of aqueous solutions containing the dextran methacrylate （Dex-MA） and hyaluronate methacrylate （HA-MA） at various macromonomer concentrations under the freezing condition. It was observed that the suitable total concen- tration of macromonomers for the preparation of Dex-HA cryogel scaffold with satisfied properties was 5% （w/w） at the HA-MA concentration of 1% （w/v）, which was then used to produce the test scaffold. The obtained cryogel scaffold with 5% （w/w） macromonomer solution had high water permeability （5.1 × 10 ^-2m2） and high porosity （92.4%）. The pore diameter examined by scanning electron microscopy （SEM） was in a broad range of 50-135 um with the mean pore diameter of 91 um. Furthermore, the cryogel scaffold also had good elastic nature with the elastic modulus of 17.47±1.44 kPa. The culture of 3T3-L1 preadipocyte within the scaffold was investigated and observed by SEM. Cells clustered on the pore walls and grew inside the scaffold indicating the Dex-HA cryogel scaffold could be a promising porous biomaterial for applications in tissue engineering.
基金Project supported partially by the Foundation of State Key Laboratory of BiomembraneMembrane Biotechnology, Institute of Zoology, the Chinese Academy of Sciences and the Foundation of Institute of Zoology, the Chinese Academy of Sciences.
文摘An in vitro cultured rat perirenal preadipocyte (PA) was established as a model system to investigate the role of the intracellular pH (pHi) and of the Na+/H+ exchanger during PA proliferation and differentiation. pH sensitive probe, 2' ,7'-bis-(2-carboxyethyl)-5(6)-carboxyfluorescein(BCECF) , was employed to measure the pHi of PA and to determine the Na+/H+ exchange activity. The results showed that there was Na+/H+ exchange activity in the plasma membrane of PA, FCS stimulated DNA synthesis measured by H-TdR incorporation, and the activation of Na + /H + exchanger resulted in pHi increase (nearly 0.2 pH unit) within 2 min. Ethyl-isopropyl-amiloride (EIPA) , a specific Na+/H+ exchange inhibitor, inhibited Na+/H+ exchange activity and DNA synthesis. In the absence of serum insulin did not stimulate DNA synthesis but did induce PA differentiation characterized by the appearance of adiposome in the cell and the enhancement of glycerol-3-phosphate dehydrogenase (G3 PDHase) activity. Meantime, insulin was also found to stimulate Na+/H+ exchange activity and pHi increase. EIPA inhibited Na+/H+ exchanger activation induced by insulin and also partially inhibited the enhancement of G3PDHase activity. These results demonstrated that the activation of Na+ /H+ exchange and the resulting pHi increase are the early events related to both proliferation and differentiation of PA.
基金supported by the following grants:CXYJ-2021-04 from the Research Foundation of Capital Institute of Pediatrics(China)81573436 from National Natural Science Foundation of China2018ZX09711-001-001-016 from the Found of the National New Drug Innovation Major Project of China。
文摘Obesity is increasingly prevalent globally, searching for therapeutic agents acting on adipose tissue is of great importance. Equisetin(EQST), a meroterpenoid isolated from a marine sponge-derived fungus, has been reported to display antibacterial and antiviral activities. Here, we revealed that EQST displayed anti-obesity effects acting on adipose tissue through inhibiting adipogenesis in vitro and attenuating HFD-induced obesity in mice, doing so without affecting food intake, blood pressure or heart rate.We demonstrated that EQST inhibited the enzyme activity of 11β-hydroxysteroid dehydrogenase type 1(11β-HSD1), a therapeutic target of obesity in adipose tissue. Anti-obesity properties of EQST were all offset by applying excessive 11β-HSD1’s substrates and 11β-HSD1 inhibition through knockdown in vitro or 11β-HSD1 knockout in vivo. In the 11β-HSD1 bypass model constructed by adding excess11β-HSD1 products, EQST’s anti-obesity effects disappeared. Furthermore, EQST directly bond to11β-HSD1 protein and presented remarkable better intensity on 11β-HSD1 inhibition and better efficacy on anti-obesity than known 11β-HSD1 inhibitor. Therefore, EQST can be developed into anti-obesity candidate compound, and this study may provide more clues for developing higher effective 11β-HSD1 inhibitors.
基金This work was supported in part by National Institutes of Health(NIH)Grant(R01DK077097)Joslin Diabetes Center’s Diabetes Research Center(P30DK03836)+1 种基金a research grant from the American Diabetes Foundation(ADA 7-12-BS-191)by funding from the Harvard Stem Cell Institute(to Y-H.T).M.D.L was supported by NIH fellowships(T32DK007260 and F32DK102320).
文摘In mammals,a thermogenic mechanism exists that increases heat production and consumes energy.Recent work has shed light on the cellular and physiological mechanisms that control this thermogenic circuit.Thermogenically active adipocytes,namely brown and closely related beige adipocytes,differentiate from progenitor cells that commit to the thermogenic lineage but can arise from different cellular origins.Thermogenic differentiation shares some features with general adipogenesis,highlighting the critical role that common transcription factors may play in progenitors with divergent fates.However,thermogenic differentiation is also discrete from the common adipogenic program and,excitingly,cells with distinct origins possess thermogenic competency that allows them to differentiate into thermogenically active mature adipocytes.An understanding of this thermogenic differentiation program and the factors that can activate it has led to the development of assays that are able to measure thermogenic activity both indirectly and directly.By combining these assays with appropriate cell models,novel therapeutic approaches to combat obesity and its related metabolic disorders by enhancing the thermogenic circuit can be developed.
