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OBJECTIVE@#To investigate the expression of pyruvate kinase M2 (PKM2) in bone marrow mesenchymal stem cells (BMSCs) in myeloma bone disease (MBD) and its effect on osteogenic and adipogenic differentiation of BMSCs.@*METHODS@#BMSCs were isolated from bone marrow of five patients with multiple myeloma (MM) (MM group) and five with iron deficiency anemia (control group) for culture and identification. The expression of PKM2 protein were compared between the two groups. The differences between osteogenic and adipogenic differentiation of BMSCs were assessed by using alkaline phosphatase (ALP) and oil red O staining, and detecting marker genes of osteogenesis and adipogenesis. The effect of MM cell line (RPMI-8226) and BMSCs co-culture on the expression of PKM2 was explored. Functional analysis was performed to investigate the correlations of PKM2 expression of MM-derived BMSCs with osteogenic and adipogenic differentiation by employing PKM2 activator and inhibitor. The role of orlistat was explored in regulating PKM2 expression, osteogenic and adipogenic differentiation of MM-derived BMSCs.@*RESULTS@#Compared with control, MM-originated BMSCs possessed the ability of increased adipogenic and decreased osteogenic differentiation, and higher level of PKM2 protein. Co-culture of MM cells with BMSCs markedly up-regulated the expression of PKM2 of BMSCs. Up-regulation of PKM2 expression could promote adipogenic differentiation and inhibit osteogenic differentiation of MM-derived BMSCs, while down-regulation of PKM2 showed opposite effect. Orlistat significantly promoted osteogenic differentiation in MM-derived BMSCs via inhibiting the expression of PKM2.@*CONCLUSION@#The overexpression of PKM2 can induce the inhibition of osteogenic differentiation of BMSCs in MBD. Orlistat can promote the osteogenic differentiation of BMSCs via inhibiting the expression of PKM2, indicating a potential novel agent of anti-MBD therapy.
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Humains , Adipogenèse , Maladies osseuses/métabolisme , Cellules de la moelle osseuse , Différenciation cellulaire , Cellules cultivées , Cellules souches mésenchymateuses/physiologie , Myélome multiple/métabolisme , Orlistat/pharmacologie , Ostéogenèse/génétiqueRésumé
The present study aimed to investigate the effect of diosgenin on mammalian target of rapamycin(mTOR), fatty acid synthase(FASN), hypoxia inducible factor-1α(HIF-1α), and vascular endothelial growth factor A(VEGFA) expression in liver tissues of rats with non-alcoholic fatty liver disease(NAFLD) and explore the mechanism of diosgenin on lipogenesis and inflammation in NAFLD. Forty male SD rats were divided into a normal group(n=8) fed on the normal diet and an experimental group(n=32) fed on the high-fat diet(HFD) for the induction of the NAFLD model. After modeling, the rats in the experimental group were randomly divided into an HFD group, a low-dose diosgenin group(150 mg·kg~(-1)·d~(-1)), a high-dose diosgenin group(300 mg·kg~(-1)·d~(-1)), and a simvastatin group(4 mg·kg~(-1)·d~(-1)), with eight rats in each group. The drugs were continuously given by gavage for eight weeks. The levels of triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C), alanine transaminase(ALT), and aspartate transaminase(AST) in the serum were detected by the biochemical method. The content of TG and TC in the liver was detected by the enzyme method. Enzyme-linked immunosorbent assay(ELISA) was used to measure interleukin 1β(IL-1β) and tumor necrosis factor α(TNF-α) in the serum. Lipid accumulation in the liver was detected by oil red O staining. Pathological changes of liver tissues were detected by hematoxylin-eosin(HE) staining. The mRNA and protein expression levels of mTOR, FASN, HIF-1α, and VEGFA in the liver of rats were detected by real-time fluorescence-based quantitative polymerase chain reaction(PCR) and Western blot, respectively. Compared with the normal group, the HFD group showed elevated body weight and levels of TG, TC, LDL-C, ALT, AST, IL-1β, and TNF-α(P<0.01), increased lipid accumulation in the liver(P<0.01), obvious liver steatosis, up-regulated mRNA expression levels of mTOR, FASN, HIF-1α, and VEGFA(P<0.01), and increased protein expression levels of p-mTOR, FASN, HIF-1α, and VEGFA(P<0.01). Compared with the HFD group, the groups with drug treatment showed lowered body weight and levels of TG, TC, LDL-C, ALT, AST, IL-1β, and TNF-α(P<0.05, P<0.01), reduced lipid accumulation in the liver(P<0.01), improved liver steatosis, decreased mRNA expression levels of mTOR, FASN, HIF-1α, and VEGFA(P<0.05, P<0.01), and declining protein expression levels of p-mTOR, FASN, HIF-1α, and VEGFA(P<0.01). The therapeutic effect of the high-dose diosgenin group was superior to that of the low-dose diosgenin group and the simvastatin group. Diosgenin may reduce liver lipid synthesis and inflammation and potentiate by down-regulating the mTOR, FASN, HIF-1α, and VEGFA expression, playing an active role in preventing and treating NAFLD.
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Rats , Mâle , Animaux , Stéatose hépatique non alcoolique/métabolisme , Facteur de croissance endothéliale vasculaire de type A/métabolisme , Facteur de nécrose tumorale alpha/métabolisme , Cholestérol LDL , Rat Sprague-Dawley , Foie , Inflammation/métabolisme , Alimentation riche en graisse/effets indésirables , Sérine-thréonine kinases TOR/métabolisme , ARN messager/métabolisme , Poids , MammifèresRésumé
Objective:To explore the effect and mechanism of small GTP-binding protein GDP dissociation stimulator (SmgGDS) on the development of obesity.Methods:(1) 8-week-old C57BL/6J mice were randomly assigned to normal diet and high fat diet group, with 6 mice in each group. They were fed regular feed and a high fat diet containing 60% fat for 4 months, respectively. The expression of SmgGDS in epididymal adipose tissue (eWAT), liver, and skeletal muscle were measured using Western-blot. (2) 6-week-old wild-type (WT) and SmgGDS knockdown (KD) mice were divided into four groups, each receiving high fat diet for 4 months (7 in each group) and 7 months (9 in each group). Glucose tolerance test (GTT) and insulin tolerance test (ITT) were conducted; the weight, adipose tissue, and liver weight of mice were recorded; HE staining examined adipose tissue structural changes; Western-blot determined extracellular signal-regulated kinase (ERK) 1/2 phosphorylation levels in eWAT; real time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect mRNA levels of CCAAT/enhancer binding protein α (C/EBPα), C/EBPβ and peroxisome proliferator activated receptor γ (PPARγ) in eWAT. (3) Mouse embryonic fibroblasts (MEFs) extracted from WT and KD mice were induced for differentiation. Oil red O staining and Western-blot were used to detect lipid droplet and expression of SmgGDS and phospho-ERK; C/EBPα, C/EBPβ and PPARγ mRNA levels were measured using RT-qPCR. (4) 10-week-old C57BL/6J mice were randomly assigned into two groups, with 7 mice in each group. Mice were infected with SmgGDS overexpressing adeno-associated virus (AAV-SmgGDS) or empty vector intraperitoneally, then fed with high fat diet. After 4 weeks, performed GTT and ITT; recorded the weight and adipose tissue weight of mice; HE staining was used to analyze structural changes of eWAT; Western-blot was used to detect the phosphorylation level of ERK in eWAT.Results:(1) The expression of SmgGDS was significantly upregulated in eWAT of high fat diet fed mice (normal diet group: 0.218±0.037, high fat diet group:0.439±0.072, t=2.74, P=0.034). (2) At 4 months of high fat diet intervention, the glucose tolerance (60 minutes after glucose injection, WT group: 528 mg/dl±21 mg/dl, KD group: 435 mg/dl±17 mg/dl, t=3.47, P=0.030; 90 minutes, WT group: 463 mg/dl±24 mg/dl, KD group: 366 mg/dl±18 mg/dl, t=3.23, P=0.047;120 minutes, WT group: 416 mg/dl±21 mg/dl, KD group: 297 mg/dl±16 mg/dl, t=4.49, P=0.005) and insulin sensitivity (15 minutes after insulin injection, WT group: 77.79%±3.45%, KD group: 54.30%±2.92%, t=3.49, P=0.005; 30 minutes, WT group: 62.27%±5.31%, KD group: 42.25%±1.85%, t=2.98, P=0.024; 90 minutes, WT group: 85.69%±6.63%, KD group: 64.71%±5.41%, t=3.12, P=0.016) of KD mice were significantly improved compared to the WT group, with an increase in eWAT weight ratio (WT: 4.19%±0.18%, KD: 5.12%±0.37%, t=2.28, P=0.042), but a decrease in average adipocyte area (WT group: 5 221 μm2±241 μm2, KD group: 4 410 μm2±196 μm2, t=2.61, P=0.026). After 7 months of high fat diet, the eWAT weight ratio of KD mice decreased (WT: 5.02%±0.20%, KD: 3.88%±0.21%, t=3.92, P=0.001) and adipocyte size decreased (WT group: 6 783 μm2±390 μm2, KD group: 4 785 μm2±303 μm2, t=4.05, P=0.002). The phospho-ERK1 in eWAT increased (WT group: 0.174±0.056, KD group: 0.588±0.147, t=2.64, P=0.025), and mRNA level of PPARγ significantly decreased (WT group: 1.018±0.128, KD group: 0.029±0.015, t=7.70, P=0.015). (3) The expression of SmgGDS was significantly increased in differentiated MEF (undifferentiated: 6.789±0.511, differentiated: 10.170±0.523, t=4.63, P=0.010); SmgGDS knock-down inhibited lipid droplet formation in MEF (WT group: 1.00±0.02, KD group: 0.88±0.02, t=5.05, P=0.007) and increased ERK1 (WT group: 0.600±0.179, KD group: 1.325±0.102, t=3.52, P=0.025) and ERK2 (WT group: 2.179±0.687, KD group: 5.200±0.814, t=2.84, P=0.047) activity, which can be reversed by ERK1/2 inhibitor. (4) SmgGDS over expression resulted in weight gain, increased eWAT weight (control group: 3.29%±0.36%, AAV-SmgGDS group: 4.27%±0.26%, t=2.20, P=0.048) and adipocyte size (control group: 3 525 μm2±454 μm2, AAV-SmgGDS group: 5 326 μm2±655 μm2, t=2.26, P=0.047), impaired insulin sensitivity(30 minutes after insulin injection, control group: 44.03%±4.29%, AAV-SmgGDS group: 62.70%±2.81%, t=3.06, P=0.019), and decreased ERK1 (control group: 0.829±0.077, AAV-SmgGDS group: 0.326±0.036, t=5.96, P=0.001) and ERK2 (control group: 5.748±0.287, AAV-SmgGDS group: 2.999±0.845, t=3.08, P=0.022) activity in eWAT. Conclusion:SmgGDS knockdown improves obesity related glucose metabolism disorder by inhibiting adipogenesis and adipose tissue hypertrophy, which is associated with ERK activation.
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Objective:To investigate the counteractive effect of mouse dermal fibroblasts (MdFBs) during their adipogenic differentiation against Staphylococcus aureus infection, and to explore its mechanisms. Methods:MdFBs were obtained from newborn C57BL/6 mice, and their adipogenic differentiation was induced by culture in an adipogenic medium for 48 hours. Real-time fluorescence-based quantitative PCR (RT-PCR) was performed to determine the mRNA expression of cathelicidin antimicrobial peptide (CAMP) on days 0-6 during the adipogenic differentiation of MdFBs, and Western blot analysis to determine the protein expression of CAMP in the culture supernatant of MdFBs during their adipogenic differentiation. MdFBs were divided into 4 groups: co-stimulation group stimulated by S. aureus suspensions and cultured in an adipogenic medium, adipogenic control group cultured in an adipogenic medium, S. aureus-stimulation group stimulated by S. aureus suspensions and cultured in a common medium, and control group stimulated by phosphate-buffered saline and cultured in a common medium; Western blot analysis and RT-PCR were conducted to determine the protein and mRNA expression of CAMP. S. aureus (5 × 10 4 CFU/ml) was cultured with the culture supernatant of MdFBs after 5-day adipogenic differentiation (adipogenic group), and the growth activity was evaluated every 2 hours during 10 - 24 hours after the start of co-culture; S. aureus cultured with the culture supernatant of MdFBs in a common medium served as the normal control group, and that cultured with cell-free culture supernatant served as the negative control group. Differences between groups were assessed using unpaired t-test or analysis of variance. Results:Significant differences were observed in the relative mRNA expression of CAMP among different time points (days 0, 1, 2, 4, and 6) during the adipogenic differentiation of MdFBs (1.14 ± 0.74, 68.04 ± 12.72, 683.12 ± 38.06, 1 390.68 ± 226.21, 454.57 ± 204.12, F = 50.08, P < 0.001) ; the CAMP mRNA expression was significantly higher on days 1, 2, 4, and 6 than on day 0 ( t = 9.09, 31.03, 10.63, 3.85, respectively, all P < 0.05), and showed an initial rise and subsequent fall during days 0 - 6. The CAMP protein expression in the culture supernatant of MdFBs peaked on days 2-5 and subsequently decreased. Significant differences were observed in the mRNA and protein expression of CAMP among the control group, S. aureus-stimulation group, adipogenic control group and co-stimulation group (mRNA: 0.08 ± 0.02, 0.38 ± 0.10, 0.49 ± 0.11, 0.80 ± 0.03, respectively, F = 43.25, P < 0.05; protein: 0.433 ± 0.176, 0.574 ± 0.176, 1.007 ± 0.176, 1.217 ± 0.176, respectively, F = 46.79, P < 0.05), and the relative mRNA and protein expression of CAMP was significantly higher in the co-stimulation group than in the adipogenic control group, S. aureus-stimulation group and control group (all P < 0.05). At 10 hours during culture, the growth activity of S. aureus was significantly lower in the adipogenic group (0.053 ± 0.015) than in the normal control group and negative control group (0.109 ± 0.015, 0.106 ± 0.015, t = 11.30, 13.26, respectively, both P < 0.05) ; during 10 - 24 hours, the growth activity of S. aureus also showed a significant decrease in the adipogenic group compared with the normal control group and negative control group (all P < 0.05) . Conclusion:MdFBs secreted CAMP during the adipogenic differentiation, and could inhibit the proliferation of S. aureus.
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@#Plant extracts are gaining popularity among researchers as alternatives from natural sources for the treatment of obesity and inhibition of adipogenic differentiation is one of the mechanisms targeted by these extracts. The main focus of this scoping review is to specifically identify the phytochemicals within the extracts, and the protein changes that occurred during adipogenesis when subjected to the various plant extracts as well as to identify the gaps in the previous studies. A systematic search was conducted using predetermined keywords on three online databases (SCOPUS, PubMed, and ScienceDirect). Overall, a total of 988 articles were retrieved, leaving only 43 articles after applying the exclusion criteria. The selected studies looked at the effects of phytochemicals found in plant extracts on the alterations in adipogenesis-related proteins that results in adipocyte differentiation inhibition mainly in 3T3-L1 cells and mice. Despite plant extracts being the basis of numerous hyperlipidemic treatments, not much is focused on the changes in adipogenic proteins such as PPARs, CEBPs, or SREBPs. Thus, in this review, we discuss how the plant extracts aid in obesity prevention, and possible further research required to fully utilize the natural sources for the betterment of public health.
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Adipose tissue is a major energy storage and endocrine organ. Adipogenesis is a complex process of cell differentiation, which is regulated by nutrient levels, hormones and metabolites, etc. The mammalian target of rapamycin (mTOR) complex includes two protein complexes, mammalian target of rapamycin complex 1 (mTORC1) and mTORC2. The lipid kinase-like domain contained in the mTOR complex lays the foundation for the mTOR pathway to regulate adipogenesis. Research on some components of mTORC1 and mTORC2 has verified the roles of mTOR in the regulation of adipogenesis. Based on previous studies, we reviewed the research of miR-199a-3p, miR-103, miR-188, Src-associated substrate in mitosis of 68 kD (Sam68), endostatin and other substances in the regulation of adipogenesis through mTORC1 and mTORC2. At the same time, we had further constructed the adipogenesis network regulated by mTOR signaling pathway, including insulin/IGF pathway, PI3K-AKT pathway, amino acid pathway, AMPK pathway, cAMP pathway, cGMP pathway, NOTCH pathway, and the modulation of bta-miR-150, 4-O-methylasochlorin and a variety of proteins. This article mainly reviewed the characteristics of mTOR complex and the latest research progress in the regulation of adipogenesis by mTOR pathway. It was pointed out that mTORC2 can regulate lipid uptake, lipolysis and regulate the function of mTORC1. However, there are fewer studies on mTORC2 compared to mTORC1, so further researches on adipogenesis and lipid metabolism may be more focused on mTORC2.
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@# Objective: To investigate the effect of Oroxylum indicum fruit extract on high-fat diet-induced hyperlipidemic mice. Methods: The phytochemical composition of Oroxylum indicum fruit extract was determined by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry. Forty-two male mice were used. The mice were divided into six groups: normal control, high-fat diet control, simvastatin treatment (20 mg/kg BW/day), and Oroxylum indicum fruit extract (100, 200, 300 mg/kg BW/day) treatment groups. Food intake, body weight, serum parameters, lipid profile, and histopathological lesions of the kidney, liver, and epididymal fat were observed. Results: LC-MS/MS results revealed four major components of Oroxylum indicum fruit extract: luteolin, apigenin, baicalein, and oroxylin A. Twenty-seven volatile oils were identified from Oroxylum indicum fruit extract. Daily oral administration of Oroxylum indicum fruit extract at 100 to 300 mg/kg BW/day significantly reduced the body weight, total cholesterol, triglyceride, and low-density lipoprotein cholesterol level (P<0.05), whereas high-density lipoprotein cholesterol was higher than the high-fat diet control group. Treatment with 300 mg/kg BW/day Oroxylum indicum fruit extract reduced the pathological lesion and prevented fat accumulation in the kidney and liver. Conclusions: Oroxylum indicum fruit extract has hypolipidemic effect in hyperlipidemic mice, and the active ingredients of Oroxylum indicum fruit extract, both flavonoids and volatile oils, should be further explored as an antihyperlipidemic agent.
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BACKGROUND: Adipogenesis and fibrogenesis can be considered as a competitive process in muscle, which may affect the intramuscular fat deposition. The CCAAT/enhancer-binding protein beta (C/EBPb) plays an important role in adipogenesis, which is well-characterized in mice, but little known in bovine so far. RESULTS: In this study, real-time qPCR revealed that the level of C/EBPb was increased during the developmental stages of bovine and adipogenesis process of preadipocytes. Overexpression of C/EBPb promoted bovine fibroblast proliferation through mitotic clonal expansion (MCE), a necessary process for initiating adipogenesis, by significantly downregulating levels of p21 and p27 (p < 0.01). Also, the PPARc expression was inhibited during the MCE stage (p < 0.01). 31.28% of transfected fibroblasts adopted lipid-laden adipocyte morphology after 8 d. Real-time qPCR showed that C/EBPb activated the transcription of early stage adipogenesis markers C/EBPa and PPARc. Expression of ACCa, FASN, FABP4 and LPL was also significantly upregulated, while the expression of LEPR was weakened. CONCLUSIONS: It was concluded C/EBPb can convert bovine fibroblasts into adipocytes without hormone induction by initiating the MCE process and promoting adipogenic genes expression, which may provide new insights into the potential functions of C/EBPb in regulating intramuscular fat deposition in beef cattle.
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Bovins/métabolisme , Adipocytes/métabolisme , Protéine bêta de liaison aux séquences stimulatrices de type CCAAT/métabolisme , Fibroblastes/métabolisme , Tissu adipeux/métabolisme , Clones cellulaires , Prolifération cellulaire , Adipogenèse , Réaction de polymérisation en chaine en temps réel , Mitose , MusclesRésumé
BACKGROUND: Lycium barbarum (also called wolfberry), a famous Chinese traditional medicine and food ingredient, is well recognized for its significant role in preventing obesity; however, the molecular mechanisms underlying its preventive effects on fat accumulation are not well understood yet. The aim of this study was to determine the effects and mechanism of Lycium barbarum polysaccharides (LBP) on the proliferation and differentiation of 3T3-L1 preadipocytes. MTT was used to detect the proliferation of 3T3-Ll preadipocytes. Oil red O staining and colorimetric analysis were used to detect cytosolic lipid accumulation during 3T3-L1 preadipocyte differentiation. Real-time fluorescent quantitative PCR (qPCR) technology was used to detect peroxisome proliferator-activated receptor c (PPARc), CCAAT/enhancer-binding protein a (C/EBPa), adipocyte fatty-acid-binding protein (aP2), fatty acid synthase (FAS), and lipoprotein lipase (LPL) expression. RESULTS: The concentration of LBP from 25 to 200 lg/mL showed a tendency to inhibit the growth of preadipocytes at 24 h, and it inhibited the differentiation of 3T3-L1 preadipocytes in a dose-dependent manner. In the preadipocytes treated with 200 lg/mL LBP, there were reduced lipid droplets in the cytoplasm, and its effect was opposite to that of rosiglitazone (ROS), which significantly reduced the PPARc, C/EBPa, aP2, FAS, and LPL mRNA expression of adipocytes. CONCLUSIONS: LBP exerts inhibitive effects on the proliferation and differentiation of 3T3-L1 preadipocytes and decreases the cytoplasm accumulation of lipid droplets during induced differentiation of preadipocytes toward mature cells. Above phenomenon might link to lowered expression of PPARc, C/EBPa, aP2, FAS, and LPL after LBP treatment. Thus, LBP could serve as a potential plant extract to treat human obesity or improve farm animal carcass quality via adjusting lipid metabolism.
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Polyosides , Extraits de plantes , Adipocytes , Lycium/composition chimique , Différenciation cellulaire , Cellules 3T3-L1 , Prolifération cellulaire , Adipogenèse , Réaction de polymérisation en chaine en temps réel/méthodesRésumé
Objective:To observe the lipogenic or osteogenic differentiation of decellularized adipose matrix (DAM) in the periosteal microenvironment.Methods:From June 2020 to December 2020, adipose tissue obtained by human liposuction was prepared as DAM at the National Institute of Plastic Surgery. Six male SD rats of 4 to 6 weeks were selected and implanted into the subperiosteum of the rat parietal bone according to the same initial volume. After 12 weeks, adipogenesis and osteogenic differentiation of DAM were observed by gross specimens, histological staining, and immunofluorescence staining. Label-free quantitative protein mass spectrometry was used for detection of osteogenic-associated proteins in DAM.Results:Vascularization around the DAM was evident. Adipogenesis and angiogenesis were observed in DAM by H&E and Masson staining, while OCN immunofluorescence staining confirmed osteogenic differentiation of DAM. The osteogenic differentiation related proteins were screened by mass spectrometry.Conclusions:In the microenvironment of periosteum, DAM mainly differentiates towards adipose tissue, but a few of them havs the potential to differentiate towards osteogenesis, which might be related to some of the osteogenesis-related proteins contained in DAM.
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BACKGROUND: The effects of dietary nutrition on tail fat deposition and the correlation between production performance and the Hh signaling pathway and OXCT1 were investigated in fat-tailed sheep. Tan sheep were fed different nutritional diets and the variances in tail length, width, thickness and tail weight as well as the mRNA expression of fat-related genes (C/EBPα, FAS, LPL, and HSL) were determined in the tail fat of sheep at three different growth stages based on their body weight. Furthermore, the correlations between tail phenotypes and the Hedgehog (Hh) signaling pathway components (IHH, PTCH1, SMO, and GLI1) and OXCT1 were investigated. RESULTS: C/EBPα, FAS, LPL, and HSL were expressed with differences in tail fat of sheep fed different nutritional diets at three different growth stages. The results of the two-way ANOVA showed the significant effect of nutrition, stage, and interaction on gene expression, except the between C/EBPα and growth stage. C/EBPα, FAS, and LPL were considerably correlated with the tail phenotypes. Furthermore, the results of the correlation analysis demonstrated a close relationship between the tail phenotypes and Hh signaling pathway and OXCT1. CONCLUSIONS: The present study demonstrated the gene-level role of dietary nutrition in promoting tail fat deposition and related tail fat-related genes. It provides a molecular basis by which nutritional balance and tail fat formation can be investigated and additional genes can be identified. The findings of the present study may help improve the production efficiency of fat-tailed sheep and identify crucial genes associated with tail fat deposition.
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Animaux , Queue/métabolisme , Ovis/génétique , Tissu adipeux , Régime alimentaire , Phénotype , ARN messager , Coenzyme A-transferases , Expression des gènes , Répartition du tissu adipeux , Adipogenèse , Lipogenèse/génétique , Protéines Hedgehog/génétique , Réaction de polymérisation en chaine en temps réelRésumé
Objective: To establish an efficacious and efficient fermentation method of enhancing the anti-adipogenesis effect of mulberry (Morus alba) leaves using Cordyceps militais. Methods: Dried mulberry leaves, dried mulberry leaves with 50% raw silkworm pupa and raw silkworm pupa were fermented with Cordyceps militais for 4 weeks at 25 °C, after which the dried mulberry leaves and fermented product were extracted with 70% ethanol and subjected to high performance liquid chromatography (HPLC). The contents of cordycepin, pelargonidin, chlorogenic acid, iso-quercetin and caffeic acid were determined. We then used the 3T3-L1 cells to investigate whether extracts of fermentation enhanced anti-adipogenesis activity in vitro. Results: HPLC showed that fermentation changed the contents of cordycepin, pelargonidin, chlorogenic acid, iso-quercetin and caffeic acid. Furthermore, fermented dried mulberry leaves with 50% raw silkworm pupa had a better efficacy of anti-adipogenesis than dried mulberry leaves, fermented dried mulberry leaves and fermented silkworm pupa and inhibited triglycerides accumulation and glucose consumption. Additionally, fermented dried mulberry leaves with 50% raw silkworm pupa inhibited PPAR-? signaling. Conclusions: Fermentation with Cordyceps militaris enhanced anti-adipogenesis efficacy of mulberry leaves.
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Objective: To establish an efficacious and efficient fermentation method of enhancing the anti-adipogenesis effect of mulberry (Morus alba) leaves using Cordyceps militais. Methods: Dried mulberry leaves, dried mulberry leaves with 50% raw silkworm pupa and raw silkworm pupa were fermented with Cordyceps militais for 4 weeks at 25 °C, after which the dried mulberry leaves and fermented product were extracted with 70% ethanol and subjected to high performance liquid chromatography (HPLC). The contents of cordycepin, pelargonidin, chlorogenic acid, iso-quercetin and caffeic acid were determined. We then used the 3T3-L1 cells to investigate whether extracts of fermentation enhanced anti-adipogenesis activity in vitro. Results: HPLC showed that fermentation changed the contents of cordycepin, pelargonidin, chlorogenic acid, iso-quercetin and caffeic acid. Furthermore, fermented dried mulberry leaves with 50% raw silkworm pupa had a better efficacy of anti-adipogenesis than dried mulberry leaves, fermented dried mulberry leaves and fermented silkworm pupa and inhibited triglycerides accumulation and glucose consumption. Additionally, fermented dried mulberry leaves with 50% raw silkworm pupa inhibited PPAR-? signaling. Conclusions: Fermentation with Cordyceps militaris enhanced anti-adipogenesis efficacy of mulberry leaves.
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Chronic energy surplus increases body fat, leading to obesity. Since obesity is closely associated with most metabolic complications, pathophysiological roles of adipose tissue in obesity have been intensively studied. White adipose tissue is largely divided into subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). These two white adipose tissues are similar in their appearance and lipid storage functions. Nonetheless, emerging evidence has suggested that SAT and VAT have different characteristics and functional roles in metabolic regulation. It is likely that there are intrinsic differences between VAT and SAT. In diet-induced obese animal models, it has been reported that adipogenic progenitors in VAT rapidly proliferate and differentiate into adipocytes. In obesity, VAT exhibits elevated inflammatory responses, which are less prevalent in SAT. On the other hand, SAT has metabolically beneficial effects. In this review, we introduce recent studies that focus on cellular and molecular components modulating adipogenesis and immune responses in SAT and VAT. Given that these two fat depots show different functions and characteristics depending on the nutritional status, it is feasible to postulate that SAT and VAT have different developmental origins with distinct adipogenic progenitors, which would be a key determining factor for the response and accommodation to metabolic input for energy homeostasis.
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Adipocytes , Adipogenèse , Tissu adipeux , Tissu adipeux blanc , Métabolisme énergétique , Main , Homéostasie , Inflammation , Graisse intra-abdominale , Modèles animaux , État nutritionnel , Obésité , Cellules souches , Graisse sous-cutanéeRésumé
BACKGROUND: The relationship between obstructive sleep apnoea (OSA) and metabolic disorders is complex and highly associated. The impairment of adipogenic capacity in pre-adipocytes may promote adipocyte hypertrophy and increase the risk of further metabolic dysfunction. We hypothesize that intermittent hypoxia (IH), as a pathophysiologic feature of OSA, may regulate adipogenesis by promoting macrophage polarization. METHODS: Male C57BL/6N mice were exposed to either IH (240 seconds of 10% O₂ followed by 120 seconds of 21% O₂, i.e., 10 cycles/hour) or intermittent normoxia (IN) for 6 weeks. Stromal-vascular fractions derived from subcutaneous (SUB-SVF) and visceral (VIS-SVF) adipose tissues were cultured and differentiated. Conditioned media from cultured RAW 264.7 macrophages after air (Raw) or IH exposure (Raw-IH) were incubated with SUB-SVF during adipogenic differentiation. RESULTS: Adipogenic differentiation of SUB-SVF but not VIS-SVF from IH-exposed mice was significantly downregulated in comparison with that derived from IN-exposed mice. IH-exposed mice compared to IN-exposed mice showed induction of hypertrophic adipocytes and increased preferential infiltration of M1 macrophages in subcutaneous adipose tissue (SAT) compared to visceral adipose tissue. Complementary in vitro analysis demonstrated that Raw-IH media significantly enhanced inhibition of adipogenesis of SUB-SVF compared to Raw media, in agreement with corresponding gene expression levels of differentiation-associated markers and adipogenic transcription factors. CONCLUSION: Low frequency IH exposure impaired adipogenesis of SAT in lean mice, and macrophage polarization may be a potential mechanism for the impaired adipogenesis.
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Animaux , Humains , Mâle , Souris , Adipocytes , Adipogenèse , Hypoxie , Milieux de culture conditionnés , Expression des gènes , Hypertrophie , Techniques in vitro , Inflammation , Graisse intra-abdominale , Macrophages , Graisse sous-cutanée , Facteurs de transcriptionRésumé
Fumigaclavine C (FC), an active indole alkaloid, is obtained from endophytic Aspergillus terreus (strain No. FC118) by the root of Rhizophora stylosa (Rhizophoraceae). This study is designed to evaluate whether FC has anti-adipogenic effects in 3T3-L1 adipocytes and whether it ameliorates lipid accumulation in high-fat diet (HFD)-induced obese mice. FC notably increased the levels of glycerol in the culture supernatants and markedly reduced lipid accumulation in 3T3-L1 adipocytes. FC differentially inhibited the expressions of adipogenesis-related genes, including the peroxisome proliferator-activated receptor proteins, CCAAT/enhancer-binding proteins, and sterol regulatory element-binding proteins. FC markedly reduced the expressions of lipid synthesis-related genes, such as the fatty acid binding protein, lipoprotein lipase, and fatty acid synthase. Furthermore, FC significantly increased the expressions of lipolysis-related genes, such as the hormone-sensitive lipase, Aquaporin-7, and adipose triglyceride lipase. In HFD-induced obese mice, intraperitoneal injections of FC decreased both the body weight and visceral adipose tissue weight. FC administration significantly reduced lipid accumulation. Moreover, FC could dose-dependently and differentially regulate the expressions of lipid metabolism-related transcription factors. All these data indicated that FC exhibited anti-obesity effects through modulating adipogenesis and lipolysis.
Sujets)
Animaux , Souris , Adipocytes , Adipogenèse , Aspergillus , Poids , Protéines de transport , Alimentation riche en graisse , Glycérol , Injections péritoneales , Graisse intra-abdominale , Triacylglycerol lipase , Lipolyse , Lipoprotein lipase , Souris obèse , Péroxysomes , Rhizophoraceae , Sterol Esterase , Facteurs de transcriptionRésumé
The biological relevance of cytokines is known for more than 20 years. Evidence suggests that adipogenesis is one of the biological events involved in the regulation of cytokines, and pro-inflammatory cytokines (e.g., TNFα and IL-1β) inhibit adipogenesis through various pathways. This inhibitory effect can constrain the hyperplastic expandability of adipose tissues. Meanwhile, chronic low-grade inflammation is commonly observed in obese populations. In some individuals, the impaired ability of adipose tissues to recruit new adipocytes to adipose depots during overnutrition results in adipocyte hypertrophy, ectopic lipid accumulation, and insulin resistance. Intervention studies showed that pro-inflammatory cytokine antagonists improve metabolism in patients with metabolic syndrome. This review focuses on the cytokines currently known to regulate adipogenesis under physiological and pathophysiological circumstances. Recent studies on how inhibited adipogenesis leads to metabolic disorders were summarized. Although the interplay of cytokines and lipid metabolism is yet incompletely understood, cytokines represent a class of potential therapeutic targets in the treatment of metabolic disorders.
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Objective To prepare polyclonal antibodies against mouse UPF1 protein and to investigate the expression of UPF1 protein during adipocyte differentiation. Methods UPF1 protein expression vector was constructed to prepare and purify rabbit UPF1 antibody. The differentation of 3T3-L1 cells was induced and the expression of UPF1 was detected by CoIP. Results 1)High specific mUPF1 polyclonal antibody was prepared and the titer of this anti-body reached 640 000;2)The expression of UPF1 protein did not change during adipogenesis;3)In the process of adipocyte differentiation,interaction of UPF1 and UPF2 was increased. Conclusions 1)The polyclonal antibodies prepared by using 550 amino acids at the C terminal of mUPF1 protein could effectively recognize intact mUPF1 pro-tein;2)The interaction of UPF1 protein with UPF2 protein during adipocyte differentiation is enhanced.
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Objective To examine the effect of miR-301b in the regulating the differentiation of mesenchymal stem cells into adipocytes.Methods Murine ST2 stromal cells were isolated,cultured and induced with adipogenic agents.The expression of miR-301b was detected by qRT-PCR in adipogenic differentiation group and control group.Stromal ST2 cells were transfected with miR-301b mimics followed by adipogenic treatment.qRT-PCR and Western blotting were conducted to detect the changes of adipocyte specific genes and protein expression levels in the miR-301b mimics transfection group and negative control(NC)transfection group. Results qRT-PCR showed that the expression of miR-301b was decreased after adipogenic treatment in ST2 cells.The relative expression level of miR-301b was less in the adipogenic differentiation group (0.219 ± 0.021) than that of the control group (1.000 ± 0.425, P<0.05). The relative expressions of peroxisome proliferator activated receptor γ(PPARγ),CCAAT/enhancer-binding protein α(C/EBPα)and adipocyte fatty acid binding proteins(aP2)were lower in the miR-301b mimics transfecting group than those in the NC transfecting group(P<0.05).The protein levels of the marker gene aP2 and transcription factors PPARγ and C/EBPα decreased in miR-310b mimics transfecting group compared with those of the NC transfecting group (P<0.05). Conclusion miR-301b can reduce adipocyte differentiation.
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BACKGROUND/OBJECTIVES: Reducing the number of adipocytes by inducing apoptosis of mature adipocytes as well as suppressing differentiation of preadipocytes plays an important role in preventing obesity. This study examines the anti-adipogenic and pro-apoptotic effect of red pepper seed water extract (RPS) prepared at 4℃ (RPS4) in 3T3-L1 cells. MATERIALS/METHODS: Effect of RPS4 or its fractions on lipid accumulation was determined in 3T3-L1 cells using oil red O (ORO) staining. The expressions of AMP-activated protein kinase (AMPK) and adipogenic associated proteins [peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding proteins α (C/EBP α), sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC)] were measured in 3T3-L1 cells treated with RPS4. Apoptosis and the expression of Akt and Bcl-2 family proteins [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad), Bcl-2 like protein 4 (Bax), Bal-2 homologous antagonist/killer (Bak)] were measured in mature 3T3-L1 cells treated with RPS4. RESULTS: Treatment of RPS4 (0–75 µg/mL) or its fractions (0–50 µg/mL) for 24 h did not have an apparent cytotoxicity on pre and mature 3T3-L1 cells. RPS4 significantly suppressed differentiation and cellular lipid accumulation by increasing the phosphorylation of AMPK and reducing the expression of PPAR-γ, C/EBP α, SREBP-1c, FAS, and ACC. In addition, all fractions except ethyl acetate fraction significantly suppressed cellular lipid accumulation. RPS4 induced the apoptosis of mature adipocytes by hypophosphorylating Akt, increasing the expression of the pro-apoptotic proteins, Bak, Bax, and Bad, and reducing the expression of the anti-apoptotic proteins, Bcl-2 and p-Bad. CONCLUSIONS: These finding suggest that RPS4 can reduce the numbers as well as the size of adipocytes and might useful for preventing and treating obesity.