Chlorogenic Acid Functions as a Novel Agonist of PPARγ2 during the Differentiation of Mouse 3T3-L1 Preadipocytes

Rosiglitazone (RG) is a well-known activator of peroxisome proliferator-activated receptor-gamma (PPARγ) and used to treat hyperglycemia and type 2 diabetes; however, its clinical application has been confounded by adverse side effects. Here, we assessed the roles of chlorogenic acid (CGA), a phenolic secondary metabolite found in many fruits and vegetables, on the differentiation and lipolysis of mouse 3T3-L1 preadipocytes. The results showed that CGA promoted differentiation in vitro according to oil red O staining and quantitative polymerase chain reaction assays. As a potential molecular mechanism, CGA downregulated mRNA levels of the adipocyte differentiation-inhibitor gene Pref1 and upregulated those of major adipogenic transcriptional factors (Cebpb and Srebp1). Additionally, CGA upregulated the expression of the differentiation-related transcriptional factor PPARγ2 at both the mRNA and protein levels. However, following CGA intervention, the accumulation of intracellular triacylglycerides following preadipocyte differentiation was significantly lower than that in the RG group. Consistent with this, our data indicated that CGA treatment significantly upregulated the expression of lipogenic pathway-related genes Plin and Srebp1 during the differentiation stage, although the influence of CGA was weaker than that of RG. Notably, CGA upregulated the expression of the lipolysis-related gene Hsl, whereas it did not increase the expression of the lipid synthesis-related gene Dgat1. These results demonstrated that CGA might function as a potential PPARγ agonist similar to RG; however, the impact of CGA on lipolysis in 3T3-L1 preadipocytes differed from that of RG.

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Role of Hyaluronan in Human Adipogenesis: Evidence from in-Vitro and in-Vivo Studies

International Journal of Molecular Sciences ◽

10.3390/ijms20112675 ◽

2019 ◽

Vol 20 (11) ◽

pp. 2675 ◽

Cited By ~ 1

Author(s):

Nicholas Wilson ◽

Robert Steadman ◽

Ilaria Muller ◽

Mohd Draman ◽

D. Aled Rees ◽

...

Keyword(s):

Stem Cell Differentiation ◽

In Vivo Studies ◽

Peroxisome Proliferator ◽

Synthesis Inhibitor ◽

Peroxisome Proliferator Activated Receptor ◽

Inhibitory Role ◽

The Impact

Hyaluronan (HA), an extra-cellular matrix glycosaminoglycan, may play a role in mesenchymal stem cell differentiation to fat but results using murine models and cell lines are conflicting. Our previous data, illustrating decreased HA production during human adipogenesis, suggested an inhibitory role. We have investigated the role of HA in adipogenesis and fat accumulation using human primary subcutaneous preadipocyte/fibroblasts (PFs, n = 12) and subjects of varying body mass index (BMI). The impact of HA on peroxisome proliferator-activated receptor gamma (PPARγ) expression was analysed following siRNA knockdown or HA synthase (HAS)1 and HAS2 overexpression. PFs were cultured in complete or adipogenic medium (ADM) with/without 4-methylumbelliferone (4-MU = HA synthesis inhibitor). Adipogenesis was evaluated using oil red O (ORO), counting adipogenic foci, and measurement of a terminal differentiation marker. Modulating HA production by HAS2 knockdown or overexpression increased (16%, p < 0.04) or decreased (30%, p = 0.01) PPARγ transcripts respectively. The inhibition of HA by 4-MU significantly enhanced ADM-induced adipogenesis with 1.52 ± 0.18- (ORO), 4.09 ± 0.63- (foci) and 2.6 ± 0.21-(marker)-fold increases compared with the controls, also increased PPARγ protein expression (40%, (p < 0.04)). In human subjects, circulating HA correlated negatively with BMI and triglycerides (r = −0.396 (p = 0.002), r = −0.269 (p = 0.038), respectively), confirming an inhibitory role of HA in human adipogenesis. Thus, enhancing HA action may provide a therapeutic target in obesity.

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The Effect of Diet on Improved Endurance in Male C57BL/6 Mice

Nutrients ◽

10.3390/nu10081101 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1101 ◽

Cited By ~ 5

Author(s):

Jin Yu ◽

Hong Zhu ◽

Saeid Taheri ◽

Stephen Perry ◽

Mark Kindy

Keyword(s):

Mitochondrial Biogenesis ◽

Fruits And Vegetables ◽

Sirtuin 1 ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor ◽

Nuclear Respiratory Factor ◽

Mitochondrial Transcription Factor ◽

Exercise Endurance ◽

The Impact

The consumption of fruits and vegetables appears to help with maintaining an adequate level of exercise and improves endurance. However, the mechanisms that are involved in this process are not well understood. In the current study, the impact of diets enriched in fruits and vegetables (GrandFusion®) on exercise endurance was examined in a mouse model. GrandFusion (GF) diets increased mitochondrial DNA and enzyme activity, while they also stimulated mitochondrial mRNA synthesis in vivo. GF diets increased both the mRNA expression of factors involved in mitochondrial biogenesis, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), mitochondrial transcription factor A (Tfam), estrogen-related receptor alpha (ERRα), nuclear respiratory factor 1 (NRF-1), cytochrome c oxidase IV (COXIV) and ATP synthase (ATPsyn). Mice treated with GF diets showed an increase in running endurance, rotarod perseverance and grip strength when compared to controls who were on a regular diet. In addition, GF diets increased the protein expression of phosphorylated AMP-activated protein kinase (AMPK), sirtuin 1 (SIRT1), PGC-1α and peroxisome proliferator-activated receptor delta (PPAR-δ), which was greater than exercise-related changes. Finally, GF reduced the expression of phosphorylated ribosomal protein S6 kinase 1 (p-S6K1) and decreased autophagy. These results demonstrate that GF diets enhance exercise endurance, which is mediated via mitochondrial biogenesis and function.

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Tissue-specific induction of 17 beta-hydroxysteroid dehydrogenase type IV by peroxisome proliferator chemicals is dependent on the peroxisome proliferator-activated receptor alpha

Journal of Endocrinology ◽

10.1677/joe.0.1580237 ◽

1998 ◽

Vol 158 (2) ◽

pp. 237-246 ◽

Cited By ~ 44

Author(s):

LQ Fan ◽

RC Cattley ◽

JC Corton

Keyword(s):

Hydroxysteroid Dehydrogenase ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

Ppar Alpha ◽

Peroxisome Proliferator Activated Receptor ◽

Receptor Alpha ◽

Protein Levels ◽

Type Iv ◽

Liver And Kidney ◽

The Impact

The 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) family of proteins regulates the levels of the active 17 beta-hydroxy forms of sex steroids. The expression of 17 beta-HSD type IV is induced by peroxisome proliferator chemicals (PPC) in rat liver. In order to characterize more generally the impact of PPC on 17 beta-HSD expression, we determined (1) if expression of other members of the 17 beta-HSD family was coordinately induced by PPC exposure, (2) the tissues in which 17 beta-HSD was induced by PPC, and (3) whether the induction of 17 beta-HSD by PPC was dependent on the peroxisome proliferator-activated receptor alpha (PPAR alpha), the central mediator of PPC effects in the mouse liver. The mRNA levels of 17 beta-HSD I, II, and III were not altered in the liver, kidney, and testis or uterus of rats treated with PPC. The mRNA or 80 kDa a full-length protein levels of 17 beta-HSD IV were strongly induced in liver and kidney, but not induced in adrenals, brown fat, heart, testis, and uterus of rats treated with diverse PPC. In liver and kidneys from treated rats, additional proteins of 66 kDa, 56 kDa, and 32 kDa were also induced which reacted with the anti-17 beta-HSD IV antibodies and were most likely proteolytic fragments of 17 bega-HSD IV. Treatment of mice which lack a functional form of PPAR alpha with PPC, demonstrated that PPC-inducibility of 17 beta-HSD IV mRNA or the 80 kDa protein was dependent on PPAR alpha expression in liver and kidney. Our results demonstrate that 17 beta-HSD IV is induced by PPC through a PPAR alpha-dependent mechanism and support the hypothesis that exposure to PPC leads to alterations in sex steroid metabolism.

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SREBP-1c/MicroRNA 33b Genomic Loci Control Adipocyte Differentiation

Molecular and Cellular Biology ◽

10.1128/mcb.00745-15 ◽

2016 ◽

Vol 36 (7) ◽

pp. 1180-1193 ◽

Cited By ~ 28

Author(s):

Nathan L. Price ◽

Brandon Holtrup ◽

Stephanie L. Kwei ◽

Martin Wabitsch ◽

Matthew Rodeheffer ◽

...

Keyword(s):

Lipid Droplet ◽

Target Genes ◽

Adipocyte Differentiation ◽

Regulatory Element ◽

Critical Role ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor ◽

The Impact

White adipose tissue (WAT) is essential for maintaining metabolic function, especially during obesity. The intronic microRNAs miR-33a and miR-33b, located within the genes encoding sterol regulatory element-binding protein 2 (SREBP-2) and SREBP-1, respectively, are transcribed in concert with their host genes and function alongside them to regulate cholesterol, fatty acid, and glucose metabolism. SREBP-1 is highly expressed in mature WAT and plays a critical role in promotingin vitroadipocyte differentiation. It is unknown whether miR-33b is induced during or involved in adipogenesis. This is in part due to loss of miR-33b in rodents, precludingin vivoassessment of the impact of miR-33b using standard mouse models. This work demonstrates that miR-33b is highly induced upon differentiation of human preadipocytes, along withSREBP-1. We further report that miR-33b is an important regulator of adipogenesis, as inhibition of miR-33b enhanced lipid droplet accumulation. Conversely, overexpression of miR-33b impaired preadipocyte proliferation and reduced lipid droplet formation and the induction of peroxisome proliferator-activated receptor γ (PPARγ) target genes during differentiation. These effects may be mediated by targeting of HMGA2, cyclin-dependent kinase 6 (CDK6), and other predicted miR-33b targets. Together, these findings demonstrate a novel role of miR-33b in the regulation of adipocyte differentiation, with important implications for the development of obesity and metabolic disease.

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Molecular mechanism of 1,25-dihydroxyvitamin D3 inhibition of adipogenesis in 3T3-L1 cells

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00410.2005 ◽

2006 ◽

Vol 290 (5) ◽

pp. E916-E924 ◽

Cited By ~ 179

Author(s):

Juan Kong ◽

Yan Chun Li

Keyword(s):

Cell Differentiation ◽

Molecular Mechanism ◽

Regulatory Element ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

Dependent Manner ◽

Dihydroxyvitamin D3 ◽

Peroxisome Proliferator Activated Receptor ◽

Protein Levels

We have investigated the molecular mechanism whereby 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] inhibits adipogenesis in vitro. 1,25(OH)2D3 blocks 3T3-L1 cell differentiation into adipocytes in a dose-dependent manner; however, the inhibition is ineffective 24–48 h after the differentiation is initiated, suggesting that 1,25(OH)2D3 inhibits only the early events of the adipogenic program. Treatment of 3T3-L1 cells with 1,25(OH)2D3 does not block the mitotic clonal expansion or C/EBPβ induction; rather, 1,25(OH)2D3 blocks the expression of C/EBPα, peroxisome proliferator-activated receptor-γ (PPARγ), sterol regulatory element-binding protein-1, and other downstream adipocyte markers. The inhibition by 1,25(OH)2D3 is reversible, since removal of 1,25(OH)2D3 from the medium restores the adipogenic process with only a temporal delay. Interestingly, although the vitamin D receptor (VDR) protein is barely detectable in 3T3-L1 preadipocytes, its levels are dramatically increased during the early phase of adipogenesis, peaking at 4–8 h and subsiding afterward throughout the rest of the differentiation program; 1,25(OH)2D3 treatment appears to stabilize the VDR protein levels. Consistently, adenovirus-mediated overexpression of human (h) VDR in 3T3-L1 cells completely blocks the adipogenic program, confirming that VDR is inhibitory. Inhibition of adipocyte differentiation by 1,25(OH)2D3 is ameliorated by troglitazone, a specific PPARγ antagonist; conversely, hVDR partially suppresses the transacting activity of PPARγ but not of C/EBPβ or C/EBPα. Moreover, 1,25(OH)2D3 markedly suppresses C/EBPα and PPARγ mRNA levels in mouse epididymal fat tissue culture. Taken together, these data indicate that the blockade of 3T3-L1 cell differentiation by 1,25(OH)2D3 occurs at the postclonal expansion stages and involves direct suppression of C/EBPα and PPARγ upregulation, antagonization of PPARγ activity, and stabilization of the inhibitory VDR protein.

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Proadipogenic effect of leptin on rat preadipocytes in vitro: activation of MAPK and STAT3 signaling pathways

AJP Cell Physiology ◽

10.1152/ajpcell.00331.2001 ◽

2002 ◽

Vol 282 (4) ◽

pp. C853-C863 ◽

Cited By ~ 95

Author(s):

F. Machinal-Quélin ◽

M. N. Dieudonné ◽

M. C. Leneveu ◽

R. Pecquery ◽

Y. Giudicelli

Keyword(s):

Subcutaneous Fat ◽

Cell Types ◽

Binding Activity ◽

Mitogen Activated Protein Kinase ◽

Cell Counting ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

Peroxisome Proliferator Activated Receptor ◽

Stat3 Phosphorylation

Because leptin has recently been shown to induce proliferation and/or differentiation of different cell types through different pathways, the aim of the present study was to investigate, in vitro, the influence of leptin on adipogenesis in rat preadipocytes. A prerequisite to this study was to identify leptin receptors (Ob-Ra and Ob-Rb) in preadipocytes from femoral subcutaneous fat. We observed that expressions of Ob-Ra and Ob-Rb increase during adipogenesis. Furthermore, leptin induces an increase of p42/p44 mitogen-activated protein kinase phosphorylated isoforms in both confluent and differentiated preadipocytes and of STAT3 phosphorylation only in confluent preadipocytes. Moreover, exposure to leptin promoted activator protein-1 complex DNA binding activity in confluent preadipocytes. Finally, exposure of primary cultured preadipocytes from the subcutaneous area to leptin (10 nM) resulted in an increased proliferation ([3H]thymidine incorporation and cell counting) and differentiation (glycerol-3-phosphate dehydrogenase activity and mRNA levels of lipoprotein lipase, peroxisome proliferator-activated receptor-γ2, and c-fos). Altogether, these results indicate that, in vitro at least, leptin through its functional receptors exerts a proadipogenic action in subcutaneous preadipocytes.

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N-Acetylcysteine Inhibits Lipids Production in Mature Adipocytes through the Inhibition of Peroxisome Proliferator-Activated Receptor 

International Journal of Biochemistry Research & Review ◽

10.9734/ijbcrr/2020/v29i430182 ◽

2020 ◽

pp. 17-29

Author(s):

Daniela Soto ◽

Claudia Martini ◽

Evelyn Frontera ◽

Laura Montaldo ◽

Maria C. Vila ◽

...

Keyword(s):

In Vitro Study ◽

Nutritional Supplement ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

Peroxisome Proliferator Activated Receptor ◽

Mrna And Protein Expression ◽

Species Production ◽

Lipids Production

Aims: Reports regarding the effects of antioxidants in obesity have been contradictory. Antioxidant N-acetylcysteine is usually considered a nutritional supplement. Our aim is to evaluate bioactivity of N-acetylcysteine (NAC) on mature adipocytes, which is a close model to in vivo condition. Study Design: In vitro study. Place and Duration of Study: Department of Basic Science (Universidad Nacional de Lujan), Department of Chemical Biology (Universidad de Buenos Aires), CONICET – INEDES and CONICET – IQUIBICEN, between March 2017 and June 2019. Methodology: We evaluated the bioactivity of different concentrations of NAC for 5 days (0.01 mM to 5 mM) on fully differentiated 3T3-L1 cells (mature adipocytes). Results: We demonstrated that NAC treatment was not toxic to mature adipocytes. Only 5mM NAC inhibited reactive oxygen species production. 5 mM NAC treatment resulted in a 60% decrease in cellular triglycerides content and inhibited 70% cholesterol accumulation. We also determined the mRNA and protein expression levels of Peroxisome Proliferator-Activated Receptor g as well as, mRNA levels of lipid protein Perilipin in NAC treated adipocytes; we observed that 5mM NAC treatment caused nearly 30% decrease in the expression of these parameters. Conclusion: These results suggest that NAC could avoid lipid accumulation in mature adipocytes; the antioxidant NAC could be beneficial in obesity treatment.

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Romidepsin Promotes Osteogenic and Adipocytic Differentiation of Human Mesenchymal Stem Cells through Inhibition of Histondeacetylase Activity

Stem Cells International ◽

10.1155/2018/2379546 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Dalia Ali ◽

Elna P. Chalisserry ◽

Muthurangan Manikandan ◽

Rimi Hamam ◽

Musaad Alfayez ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Biological Effects ◽

Quantitative Polymerase Chain Reaction ◽

Osteoblastic Differentiation ◽

Peroxisome Proliferator ◽

Dual Inhibitor ◽

Multipotent Stem Cells ◽

Peroxisome Proliferator Activated Receptor

Bone marrow mesenchymal stem cells (BMSCs) are adult multipotent stem cells that can differentiate into mesodermal lineage cells, including adipocytes and osteoblasts. However, the epigenetic mechanisms governing the lineage-specific commitment of BMSCs into adipocytes or osteoblasts are under investigation. Herein, we investigated the epigenetic effect of romidepsin, a small molecule dual inhibitor targeting HDAC1 and HDAC2 identified through an epigenetic library functional screen. BMSCs exposed to romidepsin (5 nM) exhibited enhanced adipocytic and osteoblastic differentiation. Global gene expression and signaling pathway analyses of differentially expressed genes revealed a strong enrichment of genes involved in adipogenesis and osteogenesis in romidepsin-treated BMSCs during induction into adipocytes or osteoblasts, respectively. Pharmacological inhibition of FAK signaling during adipogenesis or inhibition of FAK or TGFβ signaling during osteogenesis diminished the biological effects of romidepsin on BMSCs. The results of chromatin immunoprecipitation combined with quantitative polymerase chain reaction indicated a significant increase in H3K9Ac epigenetic markers in the promoter regions of peroxisome proliferator-activated receptor gamma (PPARγ) and KLF15 (related to adipogenesis) or SP7 (Osterix) and alkaline phosphatase (ALP) (related to osteogenesis) in romidepsin-treated BMSCs. Our data indicated that romidepsin is a novel in vitro modulator of adipocytic and osteoblastic differentiation of BMSCs.

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The Pro-Differentiation Effect of Doxycycline on Human SZ95 Sebocytes

Dermatology ◽

10.1159/000510885 ◽

2020 ◽

pp. 1-5

Author(s):

Christos C. Zouboulis ◽

Síona Ní Raghallaigh ◽

Gerd Schmitz ◽

Frank C. Powell

Keyword(s):

Lipid Content ◽

Acne Vulgaris ◽

Cell Number ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

Sebaceous Glands ◽

Peroxisome Proliferator Activated Receptor ◽

New Findings

Background: Despite their widespread clinical use in both acne vulgaris and rosacea, the effects of tetracyclines on sebocytes have not been investigated until now. Sebaceous glands are central to the pathogenesis of acne and may be important in the development of rosacea. Objective: The aim of this study was to assess the effects of doxycycline on the immortalized SZ95 sebaceous gland cell line as a model for understanding possible effectiveness on the sebaceous glands in vivo. Methods: The effects of doxycycline on SZ95 sebocyte numbers, viability, and lipid content as well as its effects on the mRNA levels of peroxisome proliferator-activated receptors α and γ, in comparison to the peroxisome proliferator-activated receptor γ agonist troglitazone, were investigated. Results: Doxycycline reduced the cell number and increased the lipid content of SZ95 sebocytes in vitro after 2 days of treatment. These doxycycline effects may be explained by an upregulation of peroxisome proliferator-activated receptor γ mRNA levels at 12 and 24 h, whereas troglitazone already upregulated peroxisome proliferator-activated receptor γ levels after 6 h. Both compounds did not influence peroxisome proliferator-activated receptor α mRNA levels. Conclusion: These new findings illustrate a previously unknown effect of doxycycline on sebocytes, which may be relevant to their modulation of disorders of the pilosebaceous unit, such as acne vulgaris and rosacea.

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High-throughput toxicogenomic screening of chemicals in the environment using metabolically competent hepatic cell cultures

npj Systems Biology and Applications ◽

10.1038/s41540-020-00166-2 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Jill A. Franzosa ◽

Jessica A. Bonzo ◽

John Jack ◽

Nancy C. Baker ◽

Parth Kothiya ◽

...

Keyword(s):

Cell Cultures ◽

Screening Program ◽

Cell Model ◽

Quantitative Polymerase Chain Reaction ◽

Pregnane X Receptor ◽

Farnesoid X Receptor ◽

Peroxisome Proliferator ◽

Molecular Signaling ◽

Peroxisome Proliferator Activated Receptor

AbstractThe ToxCast in vitro screening program has provided concentration-response bioactivity data across more than a thousand assay endpoints for thousands of chemicals found in our environment and commerce. However, most ToxCast screening assays have evaluated individual biological targets in cancer cell lines lacking integrated physiological functionality (such as receptor signaling, metabolism). We evaluated differentiated HepaRGTM cells, a human liver-derived cell model understood to effectively model physiologically relevant hepatic signaling. Expression of 93 gene transcripts was measured by quantitative polymerase chain reaction using Fluidigm 96.96 dynamic arrays in response to 1060 chemicals tested in eight-point concentration-response. A Bayesian framework quantitatively modeled chemical-induced changes in gene expression via six transcription factors including: aryl hydrocarbon receptor, constitutive androstane receptor, pregnane X receptor, farnesoid X receptor, androgen receptor, and peroxisome proliferator-activated receptor alpha. For these chemicals the network model translates transcriptomic data into Bayesian inferences about molecular targets known to activate toxicological adverse outcome pathways. These data also provide new insights into the molecular signaling network of HepaRGTM cell cultures.

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