Process Of Adipogenesis Research Articles

Cell-Intrinsic Tumorigenic Functions of PPARγ in Bladder Urothelial Carcinoma.

The role of PPAR gamma (PPARγ) has been well characterized in the developmental process of adipogenesis, yet its aberrant expression patterns and functions in cancer subtypes are less understood. Although PPARγ has been recently demonstrated to play non-cell-autonomous roles in promoting bladder urothelial carcinoma (UC) progression, underlying mechanisms of the cell-intrinsic oncogenic activity remain unknown. Here, we report robust expression and nuclear accumulation of PPARγ in 47% of samples of patients with UC, exceeding mRNA expression patterns published by The Cancer Genome Atlas. In vitro assays revealed for the first time that treatment of UC cells with PPARγ inverse agonist or PPARG knockout by CRISPR-Cas9 reduces proliferation, migration, and invasion of multiple established UC cell lines, most strongly in those characterized by PPARG genomic amplification or activating mutations of RXRA, the obligate heterodimer of PPARγ. Through genome-wide approaches including chromatin immunoprecipitation sequencing and RNA sequencing, we define a novel set of PPARγ-regulated genes in UC, including Sonic Hedgehog (SHH). Similar to PPARγ, genetic inhibition of SHH reduces proliferation and motility. Finally, we demonstrate the PPARγ dependency of UC tumors in vivo by genetic and pharmacologic PPARγ inhibition in subcutaneous xenografts. Collectively, our data indicate that PPARγ promotes UC progression in a subset of patients, at least in part, through cell-autonomous mechanisms linked to SHH signaling. IMPLICATIONS: Genome-wide analysis of DNA-binding sites for oncogenic factor PPARγ revealed SHH as a novel downstream target involved in UC progression, providing important insight into the tumorigenic nature and molecular mechanism of PPARγ signaling in UC.

Alterations of DNA methylation during adipogenesis differentiation of mesenchymal stem cells isolated from adipose tissue of patients with obesity is associated with type 2 diabetes

ABSTRACT Adipogenesis regulation is crucial for mature adipocyte function. In obesity, a major driver of type 2 diabetes (T2D), this process is disrupted and remains poorly characterized. Here we identified altered DNA methylation profiles in diabetic obese patients, during three adipocytes differentiation stages. We isolated mesenchymal cells from visceral adipose tissue of obese patients with and without T2D to analyse DNA methylation profiles at 0, 3, and 18 days of ex vivo differentiation and documented their impact on gene expression. Methylation and gene expression were analysed with EPIC and Clarion S arrays, respectively. Patients with T2D had epigenetic alterations in all the analysed stages, and these were mainly observed in genes important in adipogenesis, insulin resistance, cell death programming, and immune effector processes. Importantly, at 3 days, we found six-fold more methylated CpG alterations than in the other stages. This is the first study to document epigenetic markers that persist through all three adipogenesis stages and their impact on gene expression, which could be a cellular metabolic memory involved in T2D. Our data provided evidence that, throughout the adipogenesis process, alterations occur in methylation that might impact mature adipocyte function, cause tissue malfunction, and potentially, lead to the development of T2D.

АНАЛІЗ ЯКІСНОГО СКЛАДУ МАТРИКСНИХ МЕТАЛОПРОТЕЇНАЗ У ПАТОГЕНЕЗІ ОЖИРІННЯ, ЩО ІНДУКОВАНЕ ВИСОКОКАЛОРІЙНОЮ ДІЄТОЮ У ЩУРІВ

The problem of obesity in modern life is becoming more actual and is a serious social risk for human life. This problem is common despite social and professional affiliation, location, age and gender. Obesity is associated with an increase growth of adipose tissue. Today obesity isn't studied only as an excessive accumulation of fat in the body, but as a chronic multivariate disease associated with a number of serious metabolic, oncological, cardiological and other complications. Although a lot of research studies regulation and intracellular processes of adipogenesis, however the information about molecular mechanisms of remodeling of the extracellular matrix during an increase fat mass is limited. Matrix metalloproteinases (MMPs) can increase the plasticity of the matrix, thereby providing adipose tissue remodeling and / or adipocyte hypertrophy, play an additional role in the growth of adipose tissue associated with obesity, supporting the differentiation of adipose tissue progenitor cells. Our research is aimed at characterization of enzymatic activitiesof MMPs in adipose tissue of the rats with obesity. We found that active enzymes with a molecular weight > 100 kDa were found in the adipose tissue of rats for the development of obesity, which may result from the formation of homodimers in these pathological conditions.Also activities of the MMP-2, -9 increase during obesity. Future studies of enzymatic activity of MMPs of rat's adipocytes tissues will improve understanding the biochemical processes under the conditions of this pathology and development of new approaches to diagnosis and treatment of obesity principles.

New insights into TNFα/PTP1B and PPARγ pathway through RNF213- a link between inflammation, obesity, insulin resistance, and Moyamoya disease.

Diabetic patients are always at a higher risk of ischemic diseases like coronary artery diseases. One such ischemic carotid artery disease is Moyamoya disease (MMD) associated with diabetes Type I and II, but the causality was unclear. Ring Finger Protein 213 (RNF213) is the major susceptible gene for MMD. To understand the association between diabetes mellitus and MMD we chose the major players from both of the anomalies: insulin and RNF213. But before establishing the role of RNF213 in the insulin-regulating pathway we had to understand the involvement of RNF213 within different biological systems. For this, we have adopted a preliminary computational approach to find the prominent interactions of RNF213. Our first objective was to construct an interactome for RNF213. We have analyzed several curated databases and adapted a list of RNF213 interacting partners to develop its interactome. Then to understand the involvement of this interactome in biological functions we have analyzed major biological pathways, biological processes, and prominent clusters related to this interactome through a computational approach. Then to develop a pathway that might give clues for RNF213 involvement in the insulin regulatory pathway we have validated the intercluster and intracluster predictions and identified a regulatory pathway for RNF213. RNF213 interactome was observed to be involved in adaptive immunity with 4 major clusters; one of the clusters involved TNFα. The immune system involves several pathways, and therefore at this point, we have chosen an event-based strategy to obtain an explicit target. Immunity is mediated by pro-inflammatory cytokines like TNFα. TNFα-mediated inflammation, obesity, and insulin resistance are associated. Therefore we chose to explore the role of RNF213 in TNFα-mediated inflammation in macrophages and inflammation-mediated insulin-resistance in adipocytes. We have observed an enhancement of RNF213 gene expression by LPS mediated pro-inflammatory stimuli and suppression by PPARγ-mediated anti-inflammatory, insulin-sensitizing stimuli in macrophages, and also in adipocytes. Administration of the pro-inflammatory cytokine TNFα was able to impede the reduction in RNF213 expression during adipogenesis and this effect was observed to be mediated by PTP1B. Inactivation of PTP1B abolished RNF213 expression which in turn enhanced the adipogenesis process through enhanced PPARγ. Constitutive expression of RNF213 suppressed the adipocyte differentiation by the inhibition of PPARγ. We could show the regulation of RNF213 by TNFα/PTP1B pathway and PPARγ. The constitutive expression of RNF213 during adipogenesis appears to be an adipostatic measure that obese patients acquire to inhibit further adipogenesis. This is verified in silico by analyzing the gene expression data obtained from the Gene Expression Omnibus database, which showed a higher expression of RNF213 in adipose tissue samples of obese people. Overall this study gives new insights into the TNFα-mediated pathway in adipogenesis and suggests the role of RNF213 in adipogenesis via this pathway.

Morolic Acid 3-O-Caffeate Inhibits Adipogenesis by Regulating Epigenetic Gene Expression.

Obesity causes a wide range of metabolic diseases including diabetes, cardiovascular disease, and kidney disease. Thus, plenty of studies have attempted to discover naturally derived compounds displaying anti-obesity effects. In this study, we evaluated the inhibitory effects of morolic acid 3-O-caffeate (MAOC), extracted from Betula schmidtii, on adipogenesis. Treatment of 3T3-L1 cells with MAOC during adipogenesis significantly reduced lipid accumulation and decreased the expression of adiponectin, a marker of mature adipocytes. Moreover, the treatment with MAOC only during the early phase (day 0–2) sufficiently inhibited adipogenesis, comparable with the inhibitory effects observed following MAOC treatment during the whole processes of adipogenesis. In the early phase of adipogenesis, the expression level of Wnt6, which inhibits adipogenesis, increased by MAOC treatment in 3T3-L1 cells. To identify the gene regulatory mechanism, we assessed alterations in histone modifications upon MAOC treatment. Both global and local levels on the Wnt6 promoter region of histone H3 lysine 4 trimethylation, an active transcriptional histone marker, increased markedly by MAOC treatment in 3T3-L1 cells. Our findings identified an epigenetic event associated with inhibition of adipocyte generation by MAOC, suggesting its potential as an efficient therapeutic compound to cure obesity and metabolic diseases.

A new phytocosmetic preparation from Thymus vulgaris stimulates adipogenesis and controls skin aging process: In vitro studies and topical effects in a double-blind placebo-controlled clinical trial.

The use of the injectable products for soft tissue augmentation and treatment of skin aging is an uncomfortable, invasive and related to several complications, and chronic reactions, mainly after long-term application. Efforts to develop new topically active anti-aging products with fewer adverse effects are a huge challenge that should be faced. We evaluated the anti-aging effects of a phytocosmetic preparation containing Thymus vulgaris associated with lecithin (ThymLec) on the facial wrinkles, expression lines, and face oval remodeling using a double-blind placebo-controlled clinical trial and in vitro cell culture assays. A clinical trial was conducted to evaluate the effects of ThymLec 2% on the area, length, and depth of the perioral and crow's feet wrinkles, nasolabial and smile lines, as well as face oval remodeling in female volunteers using a sophisticated Bio3D Structured-light Scanner. In the in vitro studies using 3T3-L1 mouse embryonic fibroblasts, adiponectin was measured by immunoenzymatic assay, adipogenesis by the AdipoRed reagent method, and the PPAR-γ expression by RT-PCR analysis. Topical treatment with ThymLec 2% reduced facial wrinkles and expression lines promoting a face oval remodeling. In the in vitro studies, ThymLec upregulated the PPAR-γ expression increasing adiponectin production and stimulating the adipogenesis process. The phytocosmetic preparation containing Thymus vulgaris and lecithin is an innovative and safe topical anti-aging product promoting fat tissue augmentation by adipogenesis stimulation via the upregulation of PPAR-γ expression and adiponectin production.

Obesity related microRNA‑424 is regulated by TNF‑α in adipocytes.

In recent years, obesity has become a major public health concern. Obesity has been previously associated with low‑grade inflammation and TNF‑α induction in adipose tissue, which subsequently disrupts adipocyte metabolism. MicroRNAs (miRNAs/miRs) are important metabolic factors and their dysregulation has been associated with obesity‑related metabolic syndromes. In fact, it has been directly suggested that miR‑424 may be functionally associated with adipogenesis, although its exact role in this process remains unclear. The present study aimed to identify the function of miR‑424 in adipogenesis. In the present study, miR‑424 expression levels were analyzed during adipogenesis and the differential expression of this miRNA in the adipose tissue of obese and non‑obese children was also assessed. Furthermore, the interaction between miR‑424 and the adipocytokine TNF‑α was determined. Finally, miR‑424 target genes and downstream signaling pathways were predicted via bioinformatics and analyzed by performing a luciferase reporter assay to elucidate the functional mechanisms of miR‑424 in adipogenesis of visceral adipocytes. The results revealed that the expression levels of miR‑424 upregulated in the adipose tissue biopsies from obese children compared with the biopsies of non‑obese children. However, in cultured adipocytes, the expression levels of miR‑424 were discovered to be gradually downregulated during the adipogenesis process. TNF‑α treatment significantly downregulated the expression levels of miR‑424 via binding to its promoter region and reducing its transcriptional activity. Through bioinformatic prediction analysis, miR‑424 target genes were analyzed, of which several were identified to be involved in signaling pathways that are known to regulate adipogenesis, such as the Wnt signaling pathway. In conclusion, the present study indicated that miR‑424 was regulated by TNF‑α and served an important role in adipogenesis.

Gut microbiota and metabolic marker alteration following dietary isoflavone-photoperiod interaction.

IntroductionThe interaction between isoflavones and the gut microbiota has been highlighted as a potential regulator of obesity and diabetes. In this study, we examined the interaction between isoflavones and a shortened activity photoperiod on the gut microbiome.MethodsMale mice were exposed to a diet containing no isoflavones (NIF) or a regular diet (RD) containing the usual isoflavones level found in a standard vivarium chow. These groups were further divided into regular (12L:12D) or short active (16L:8D) photoperiod, which mimics seasonal changes observed at high latitudes. White adipose tissue and genes involved in lipid metabolism and adipogenesis processes were analysed. Bacterial genomic DNA was isolated from fecal boli, and 16S ribosomal RNA sequencing was performed.ResultsNIF diet increased body weight and adipocyte size when compared to mice on RD. The lack of isoflavones and photoperiod alteration also caused dysregulation of lipoprotein lipase (Lpl), glucose transporter type 4 (Glut‐4) and peroxisome proliferator‐activated receptor gamma (Pparg) genes. Using 16S ribosomal RNA sequencing, we found that mice fed the NIF diet had a greater proportion of Firmicutes than Bacteroidetes when compared to animals on the RD. These alterations were accompanied by changes in the endocrine profile, with lower thyroid‐stimulating hormone levels in the NIF group compared to the RD. Interestingly, the NIF group displayed increased locomotion as compared to the RD group.ConclusionTogether, these data show an interaction between the gut bacterial communities, photoperiod length and isoflavone compounds, which may be essential for understanding and improving metabolic health.

Comparative Proteomic Profiling of 3T3-L1 Adipocyte Differentiation Using SILAC Quantification.

Adipocyte differentiation is a general physiological process that is also critical for metabolic syndrome. In spite of extensive study in the past two decades, adipogenesis is a still complex cellular process that is accompanied by complicated molecular mechanisms. Here, we performed SILAC-based quantitative global proteomic profiling of 3T3-L1 adipocyte differentiation. We report protein changes to the proteome profiles, with 354 proteins exhibiting significant increase and 56 proteins showing decrease in our statistical analysis. Our results show that adipocyte differentiation is involved not only in metabolic processes by increasing TCA cycle, fatty acid synthesis, lipolysis, acetyl-CoA production, antioxidants, and electron transport, but also in nicotinamide metabolism, cristae formation, mitochondrial protein import, and Ca2+ transport into mitochondria and ER. A search for Chromosome-Centric Human Proteome Project (C-HPP) using neXtprot highlighted one protein with a protein existence uncertain (PE5) and 17 proteins as functionally uncharacterized protein existence 1 (uPE1). This study provides quantitative information on proteome changes in adipogenic differentiation, which is helpful in improving our understanding of the processes of adipogenesis.

Brucella abortus Infection Modulates 3T3-L1 Adipocyte Inflammatory Response and Inhibits Adipogenesis.

Brucellosis is a prevalent global zoonotic infection but has far more impact in developing countries. The adipocytes are the most abundant cell type of adipose tissue and their secreted factors play an important role in several aspects of the innate and adaptive immune response. Here, we demonstrated the ability of Brucella abortus to infect and replicate in both adipocytes and its precursor cells (pre-adipocytes) derived from 3T3-L1 cell line. Additionally, infection of pre-adipocytes also inhibited adipogenesis in a mechanism independent of bacterial viability and dependent on lipidated outer membrane protein (L-Omp19). B. abortus infection was able to modulate the secretion of IL-6 and the matrix metalloproteases (MMPs) -2 and-9 in pre-adipocytes and adipocytes, and also modulated de transcription of adiponectin, leptin, and resistin in differentiated adipocytes. B. abortus-infected macrophages also modulate adipocyte differentiation involving a TNF-α dependent mechanism, thus suggesting a plausible interplay between B. abortus, adipocytes, and macrophages. In conclusion, B. abortus is able to alter adipogenesis process in adipocytes and its precursors directly after their infection, or merely their exposure to the B. abortus lipoproteins, and indirectly through soluble factors released by B. abortus-infected macrophages.

Small RNA sequencing reveals a novel tsRNA-06018 playing an important role during adipogenic differentiation of hMSCs.

Transfer RNA‐derived small RNAs (tsRNAs), a novel type of non‐coding RNA derivative, are able to regulate a wide range of biological processes. What role these tsRNAs play in the regulation of human bone marrow mesenchymal stem cell (hMSCs) adipogenic differentiation remains uncertain. We induced the adipogenic differentiation of human bone marrow mesenchymal cells (hMSCs) and then performed small RNA transcriptomic sequencing, leading us to identify tsRNA‐06018 as a target of interest based upon resultant the tsRNA expression profiles. When tsRNA‐06018 was knocked down, this led to the inhibition of adipogenesis and a decrease in adipogenic marker expression. When STC2 was overexpressed, this impaired the adipogenic differentiation of these cells. We further used luciferase reporter assays to confirm that tsRNA‐06018 directly binds the 3′‐untranslated region (3′‐UTR) of STC2. In addition, we determined that both knocking down tsRNA‐06018 and overexpressing STC2 increased extracellular signal‐regulated kinase 1/2 (ERK1/2) phosphorylation within cells. We also assessed that the adipogenic differentiation of hMSCs in which tsRNA‐06018 was knocked down was further enhanced upon the addition of the ERK1/2 inhibitor U0126 as compared tsRNA‐06018 knockdown alone. Taken together, using small RNA sequencing we profiled tsRNAs in hMSCs during the process of adipogenesis, leading us to identify tsRNA‐06018 as a novel regulator of this differentiation process. This tsRNA was able to regulate adipogenic differentiation by targeting STC2 via the ERK1/2 signalling pathway.

Regulation of bone marrow mesenchymal stem cell fate by long non-coding RNA.

Bone mesenchymal stem cells (BMSCs) are progenitor cells isolated from bone marrow, which keep potential to differentiate into several kinds of cells including osteoblasts and adipocytes. A dynamic mutual regulation exists between osteogenesis and adipogenesis processes. Long non-coding RNA (lncRNA) performs diverse functions in biological activities including regulation of BMSCs commitment. Evidence has shown that lncRNA regulates key signaling pathways including TGFβ/BMP, Wnt and Notch pathways, and several transcription factors in BMSCs differention. Dysregulation of lncRNA in BMSCs leads to disruption of osteo-adipogenesis difffrentiation and results in impairment of bone homeostasis. In this review, we focus on the role of lncRNA in several critical signaling pathways that involved in regulation of osteo-adipogenesis of BMSC and prospects the potential clinical application of lncRNA.

Effects of Viburnum opulus fruit extracts on adipogenesis of 3T3-L1 cells and lipase activity

In this study, the anti-obesity effect and mechanism of action of Viburnim opulus fruit crude extract (CE) and semi-purified phenolic extract (SPPE) in 3T3-L1 cells were studied. In addition, inhibitory activity of extracts against pancreatic lipase in triolein emulsion was estimated, as well as their phenolic profiles by UPLC/Q-TOF-MS. Twenty four phenolic compounds were identified in both extracts with chlorogenic acid as the dominant compound. The inhibition mode of extracts against lipase was competitive and SPPE demonstrated synergistic action with orlistat. Both extracts had the ability to inhibit adipogenesis process in a dose-dependent manner. Cells treatment with extracts at 75 µg/mL concentration was not only sufficient to inhibit lipids accumulation at almost 20%, but also influenced the size of lipid droplets. CE and SPPE reduced intracellular reactive oxygen species production by 20% and leptin level by 21–30%. They did not affect the peroxisome proliferator-activated receptor-gamma and adiponectin protein expression levels.

Viburnum opulus L. Juice Phenolics Inhibit Mouse 3T3-L1 Cells Adipogenesis and Pancreatic Lipase Activity.

Viburnum opulus L. fruit is a rich source of phenolic compounds that may be involved in the prevention of metabolic diseases. The purpose of this study was to determine the effects of Viburnum opulus fresh juice (FJ) and juice purified by solid-phase extraction (PJ) on the adipogenesis process with murine 3T3-L1 preadipocyte cell line and pancreatic lipase activity in triolein emulsion, as well as their phenolic profiles by UPLC/Q-TOF-MS. Decrease of lipids and triacylglycerol accumulation in differentiated 3T3-L1 cells were in concordance with downregulation of the expression of peroxisome proliferator-activated receptor-gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPβ/α), and sterol regulatory element-binding protein 1c (SREBP-1c). Furthermore, regulation of PPARγ-mediated β-lactamase expression by V. opulus components in reporter gene assay, as well as their binding affinity to ligand-binding domain of PPARγ, were tested. In addition, the levels of enzymes involved in lipid metabolism, like fatty acid synthase (FAS) or acetyl-CoA carboxylase (ACC), were decreased, along with inflammatory cytokines, like tumor necrosis factorα (TNFα), interleukin-6 (Il-6) and leptin. Moreover, FJ and PJ were able to inhibit pancreatic lipase, which potentially could reduce the fat absorption from the intestinal lumen and the storage of body fat in the adipose tissues. Thirty-two phenolic compounds with chlorogenic acid as the dominant compound were identified in PJ which revealed significant biological activity. These data contribute to elucidate V. opulus juice phenolic compounds’ molecular mechanism in adipogenesis regulation in 3T3-L1 cells and dietary fat lipolysis.

Differentially Expressed miRNA-Gene Targets Related to Intramuscular Fat in Musculus Longissimus Dorsi of Charolais × Holstein F2-Crossbred Bulls.

Intramuscular fat (IMF) is a meat quality indicator associated with taste and juiciness. IMF deposition, influenced by genetic and non-genetic factors, occurs through a transcriptionally coordinated process of adipogenesis. MicroRNAs (miRNAs) are transcriptional regulators of vital biological processes, including lipid metabolism and adipogenesis. However, in bovines, limited data on miRNA profiling and association with divergent intramuscular fat content, regulated exclusively by genetic parameters, have been reported. Here, a microarray experiment was performed to identify and characterize the miRNA expression pattern in the Musculus longissimus dorsi of F2-cross (Charolais × German Holstein) bulls with high and low IMF. A total of 38 differentially expressed miRNAs (DE miRNAs), including 33 upregulated and 5 downregulated (corrected p-value ≤ 0.05, FC ≥ ±1.2), were reported. Among DE miRNAs, the upregulated miRNAs miR-105a/b, miR-695, miR-1193, miR-1284, miR-1287-5p, miR-3128, miR-3178, miR-3910, miR-4443, miR-4445 and miR-4745, and the downregulated miRNAs miR-877-5p, miR-4487 and miR-4706 were identified as novel fat deposition regulators. DE miRNAs were further analyzed, along with previously identified differentially expressed genes (DEGs) from the same samples and predicted target genes, using multiple bioinformatic approaches, including target prediction tools and co-expression networks, as well as Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. We identified DE miRNAs and their gene targets associated with bovine intramuscular adipogenesis, and we provide a basis for further functional investigations.

Gaucher disease-associated alterations in mesenchymal stem cells reduce osteogenesis and favour adipogenesis processes with concomitant increased osteoclastogenesis

Gaucher disease (GD) is caused by pathogenic mutations in GBA1, the gene that encodes the lysosomal enzyme β-glucocerebrosidase. Until now, treatments for GD cannot completely reverse bone problems. The aim of this work was to evaluate the potential of MSCs from GD patients (GD MSCs) to differentiate towards the osteoblast (GD Ob) and adipocyte (GD Ad) lineages, and their role in osteoclastogenesis. We observed that GD Ob exhibited reduced mineralization, collagen deposition and alkaline phosphatase activity (ALP), as well as decreased gene expression of RUNX2, COLA1 and ALP. We also evaluated the process of osteoclastogenesis and observed that conditioned media from GD MSCs supernatants induced an increase in the number of osteoclasts. In this model, osteoclastogenesis was induced by RANKL and IL-1β. Furthermore, results showed that in GD MSCs there was a promotion in NLRP3 and PPAR-γ gene expression. Adipogenic differentiation revealed that GD Ad had an increase in PPAR-γ and a reduced RUNX2 gene expression, promoting adipocyte differentiation. In conclusion, our results show that GD MSCs exhibited deficient GD Ob differentiation and increased adipogenesis. In addition, we show that GD MSCs promoted increased osteoclastogenesis through RANKL and IL-1β. These changes in GD MSCs are likely to contribute to skeletal imbalance observed in GD patients.

The mechanisms of baicalin ameliorate obesity and hyperlipidemia through a network pharmacology approach

Obesity is one of the main causes of human cardiovascular and cerebrovascular diseases. Baicalin, a bioactive flavonoid isolated from the herbal medicine Scutellaria baicalensis Georgi, is reported to ameliorate obesity and hyperlipidemia. However, its mechanism remains unclear. Here, we used network pharmacology to explore the potential mechanism of baicalin on a system level. First, we predicted the targets of baicalin and diseases, and then protein-protein interaction (PPI) networks were constructed. Moreover, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment was performed via the Database for Annotation, Visualization, and Integrated Discovery (DAVID) server. Lastly, we confirmed the results of the network analysis by palmitic acid (PA) treated human hepatoma cells (HepG2) in vitro. The results indicated that 37 targets related to obesity treated by baicalin were predicted by network pharmacology, and top 10 related pathways were extracted by the KEGG database. Baicalin treatment could reduce triglyceride (TG) contents and lipid droplet accumulation in PA-treated HepG2 cells. The anti-obesity effects of baicalin might be due to the up-regulation of solute carrier family 2 member 1 (SLC2A1) and down-regulation of tumor necrosis factor (TNF), nuclear factor kappa B subunit 1 (NFKB1), sterol regulatory element binding transcription factor 1 (SREBF1), peroxisome proliferator activated receptor gamma and caspase 3 (CASP3). Our results indicated that baicalin may regulate key inflammatory markers, adipogenesis process, and apoptosis for treatment of obesity.

Anti-obesity Effect of Gold Nanoparticles fromDendropanax morbifera Léveilleby Suppression of Triglyceride Synthesis and Downregulation of PPARγ and CEBPα Signaling Pathways in 3T3-L1 Mature Adipocytes and HepG2 Cells

Background:Biosynthesis of gold nanoparticles from medicinal plants has become an interesting strategy in biomedical research due to its exclusive properties including less toxic cellular level through its ecofriendly biological function.Objective:To examine the anti-lipid accumulation effect of spherical gold nanoparticles (size 10-20 nm) synthesized from Dendropanax morbifera Léveille (D-AuNPs) in both 3T3-L1 and HepG2 cells.Method:3T3-L1 preadipocytes and HepG2 hepatocytes were stimulated with cocktail media to generate obese and fatty liver disease models. Cell cytotoxicity and cell proliferation assays were performed in adipocytes at different stages of growth. An anti-lipid accumulation assay was performed in 3T3-L1 obese and HepG2 fatty liver models using different doses of D-AuNPs. Expression of adipogenic genes of PPARγ, CEBPα, Jak2, STAT3, and ap2 and hepatogenic genes PPARα, FAS, and ACC was measured by real-time PCR. In addition, protein expression of PPARγ and CEBPα was evaluated by immunoblotting assay.Result:We found that D-AuNPs (size 10–20 nm) at concentrations up to 100 µg/ml were nontoxic to 3T3-L1 and HepG2 at post-confluent and mature stages. In addition, pretreatment of D-AuNPs at post-confluent stage reduced triglyceride content. In addition, the adipogenesis process was negatively controlled by D-AuNPs, with downregulated PPARγ, CEBPα, Jak2, STAT3, and ap2 expression in 3T3-L1 cells and FAS and ACC levels in HepG2 cells.Conclusion:These data indicated that D-AuNPs exert antiadipogenic properties. We hypothesize that Dendropanax contains a large amount of phenolic compound that coats the surface of gold nanoparticles and has the ability to reduce the excess amount of lipid in both cell lines.

Induction of DEAD Box helicase 5 in early adipogenesis is regulated by Ten-eleven translocation 2

Dead box helicase 5 (DDX5) is an RNA helicase that is has cellular function on RNA splicing and transcriptional regulation. It has been reported to be involved in cell differentiation including adipogenesis. However, it is not clear how DDX5 is regulated during adipogenesis. Our previous report demonstrated that the Ten-eleven translocation methyl-cytosine dioxygenase 2 (TET2) is required for adipogenesis. This study was aimed to investigate DDX5 as a direct target of TET2 upon adipogenic induction of 3T3-L1 preadipocyte. Microarray-based screening of differentially expressed genes upon TET2 knockdown identified genes involved in cell cycle, DNA replication, and ribosome biology as major targets of TET2 in the initial step of adipogenic induction. The Ddx5 gene was identified and validated as the target. TET2-mediated epigenetic regulation of the Ddx5 gene was measured by two independent methods including immunoprecipitation against 5-hydroxymethylcytosine (5hmC) and 5-methylcytosine (5mC) as well as EpiMark 5hmC and 5mC analysis. Ddx5 expression was downregulated upon TET2 knockdown, coincided with a significant decrease of 5hmC at the Ddx5 locus. DDX5 knockdown significantly suppressed adipogenesis, while DDX5 overexpression promoted it. Importantly, DDX5 overexpression, when co-transfected, rescued the process of adipogenesis, which was hindered by TET2 siRNA treatment. The findings suggest TET2-mediated regulation of the Ddx5 gene is required for an initial step of adipogenesis.

Meat Protein in High-Fat Diet Induces Adipogensis and Dyslipidemia by Altering Gut Microbiota and Endocannabinoid Dysregulation in the Adipose Tissue of Mice.

Endocannabinoids modulate insulin and adipokine expression in adipocytes through cannabinoid receptors and their levels are elevated during hyperglycemia and obesity, but little is known about how diets affect them. We assessed the effects of dietary casein, chicken, beef, and pork proteins in a high-fat diet mode, on endocannabinoids, adipogenesis, and biomarkers associated with dyslipemdia. A high-fat beef or chicken diet upregulated cannabinoid 1 receptor, N-acyl phosphatidylethanolamine-selective phospholipase-D and diacylglycerol lipase α in adipose tissue and reduced the immunoreactivity of mitochondrial uncoupling protein 1 in brown adipose tissue. In addition, the high-fat diets with beef and chicken protein had a significant impact on adipocyte differentiation and mitochondrial biogenesis in obese mice. A 16S rRNA gene sequencing indicated that high-fat diets, regardless of the protein source, significantly enhanced the ratio of Firmicutes to Bacteroidetes in colon. Meat proteins in a high-fat diet significantly decreased the relative abundances of Akkermansia and Bifidobacteria but enhanced the lipopolysaccharides level in the serum, which promoted the adipogenesis process by causing dysregulation in the endocannabinoid receptors. Consumption of meat protein with high-fat-induced adiposity, visceral obesity, and dyslipidemia reduced the thermogenesis and had a distinctive effect on the mitochondrial biogenesis compared with casein protein.