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Biochimica Et Biophysica Acta.... Jun 2024The functional differences between preadipocytes and fully differentiated mature adipocytes derived from stromal vascular fraction stem cells, as well as primary...
The functional differences between preadipocytes and fully differentiated mature adipocytes derived from stromal vascular fraction stem cells, as well as primary adipocytes have been analysed by evaluating their response to the obesogenic factor (a saturated fatty acid) and TNF-triggered inflammation. The analysis of single adipocytes shows that the saturated fatty acid (palmitic acid) accumulation is accompanied by inflammation and considerably dependent on the stage of the adipogenesis. In particular, preadipocytes show the exceptional potential for palmitic acid uptake resulting in their hypertrophy and the elevated cellular expression of the inflammation marker (ICAM-1). Our research provides new information on the impact of obesogenic factors on preadipocytes that is important in the light of childhood obesity prevention.
PubMed: 38876269
DOI: 10.1016/j.bbalip.2024.159525 -
Biochemistry and Biophysics Reports Jul 2024The estrogen-synthesizing enzyme aromatase is expressed in adipose tissue where it controls the local concentration of estrogen. It has been suggested that the organic...
The estrogen-synthesizing enzyme aromatase is expressed in adipose tissue where it controls the local concentration of estrogen. It has been suggested that the organic solvents ethanol and ethylene glycol can induce estrogen synthesis by inhibiting PPARγ activity. Since elevated estrogen synthesis in adipose tissue is a risk factor for breast cancer development, it is of interest to further characterize the mechanisms regulating aromatase expression. Here, we explored the mechanisms by which ethanol and ethylene glycol modulate aromatase mRNA expression and the ultimate conversion of androgens into estrogens. NMR spectroscopy revealed that ethanol and ethylene glycol influence the active state of PPARγ. An inhibitory effect on PPARγ was confirmed by adipogenesis assays and PPARγ target gene expression analysis in adipocytes. However, only ethanol increased aromatase mRNA in differentiated human adipocytes. In contrast, ethylene glycol downregulated aromatase in a PPARγ-independent manner. An animal study using female Wistar rats was conducted to assess the acute effects of ethanol and ethylene glycol on aromatase expression in adipose tissue within a physiological context. No changes in aromatase or PPARγ target gene ( and ) levels were observed in adipose tissue or ovary in response to the chemical exposures, suggesting an absence of acute PPARγ-mediated effects in these organs. The results suggest that ethanol and ethylene glycol are weak PPARγ antagonists in mouse and human adipocytes as well as in cell-free NMR spectroscopy. Both compounds seem to affect adipocyte aromatase expression , where ethanol increased aromatase expression PPARγ-dependently and ethylene glycol decreased aromatase expression independently of PPARγ. No acute effects on aromatase expression or PPARγ activity were observed in adipose tissue or ovary in rats in this study design.
PubMed: 38873224
DOI: 10.1016/j.bbrep.2024.101742 -
Ecotoxicology and Environmental Safety Jun 2024Tetrabromobisphenol A (TBBPA), a widely-used brominated flame retardant, has been revealed to exert endocrine disrupting effects and induce adipogenesis. Given the high...
Tetrabromobisphenol A (TBBPA), a widely-used brominated flame retardant, has been revealed to exert endocrine disrupting effects and induce adipogenesis. Given the high structural similarities of TBBPA analogues and their increasing exposure risks, their effects on lipid metabolism are necessary to be explored. Herein, 9 representative TBBPA analogues were screened for their interference on 3T3-L1 preadipocyte adipogenesis, differentiation of C3H10T1/2 mesenchymal stem cells (MSCs) to brown adipocytes, and lipid accumulation of HepG2 cells. TBBPA bis(2-hydroxyethyl ether) (TBBPA-BHEE), TBBPA mono(2-hydroxyethyl ether) (TBBPA-MHEE), TBBPA bis(glycidyl ether) (TBBPA-BGE), and TBBPA mono(glycidyl ether) (TBBPA-MGE) were found to induce adipogenesis in 3T3-L1 preadipocytes to different extends, as evidenced by the upregulated intracellular lipid generation and expressions of adipogenesis-related biomarkers. TBBPA-BHEE exhibited a stronger obesogenic effect than did TBBPA. In contrast, the test chemicals had a weak impact on the differentiation process of C3H10T1/2 MSCs to brown adipocytes. As for hepatic lipid formation test, only TBBPA mono(allyl ether) (TBBPA-MAE) was found to significantly promote triglyceride (TG) accumulation in HepG2 cells, and the effective exposure concentration of the chemical under oleic acid (OA) co-exposure was lower than that without OA co-exposure. Collectively, TBBPA analogues may perturb lipid metabolism in multiple tissues, which varies with the test tissues. The findings highlight the potential health risks of this kind of emerging chemicals in inducing obesity, non-alcoholic fatty liver disease (NAFLD) and other lipid metabolism disorders, especially under the conditions in conjunction with high-fat diets.
PubMed: 38870736
DOI: 10.1016/j.ecoenv.2024.116577 -
Controlled Quercetin Release by Fluorescent Mesoporous Nanocarriers for Effective Anti-Adipogenesis.International Journal of Nanomedicine 2024Quercetin (QUER), a flavonoid abundant in fruits and vegetables, is emerging as a promising alternative therapeutic agent for obesity treatment due to its antioxidant...
INTRODUCTION
Quercetin (QUER), a flavonoid abundant in fruits and vegetables, is emerging as a promising alternative therapeutic agent for obesity treatment due to its antioxidant and anti-adipogenic properties. However, the clinical application of QUER is limited by its poor solubility, low bioavailability, and potential toxicity at high doses. To address these challenges, this study aims to develop an advanced drug delivery system using fluorescent mesoporous silica nanoparticles (FMSNs) coated with polydopamine (PDA) for the efficient and sustained delivery of QUER to inhibit adipogenesis.
METHODS
The research included the synthesis of PDA-coated FMSNs for encapsulation of QUER, characterization of their mesoporous structures, and systematic investigation of the release behavior of QUER. The DPPH assay was used to evaluate the sustained radical scavenging potential. Concentration-dependent effects on 3T3-L1 cell proliferation, cellular uptake and adipogenesis inhibition were investigated.
RESULTS
PDA-coated FMSNs exhibited well-aligned mesoporous structures. The DPPH assay confirmed the sustained radical scavenging potential, with FMSNs-QUER@PDA showing 53.92 ± 3.48% inhibition at 72 h, which was higher than FMSNs-QUER (44.66 ± 0.57%) and free QUER (43.37 ± 5.04%). Concentration-dependent effects on 3T3-L1 cells highlighted the enhanced efficacy of PDA-coated FMSNs for cellular uptake, with a 1.5-fold increase compared to uncoated FMSNs. Adipogenesis inhibition was also improved, with relative lipid accumulation of 44.6 ± 4.6%, 37.3 ± 4.6%, and 36.5 ± 7.3% at 2.5, 5, and 10 μM QUER concentrations, respectively.
CONCLUSION
The study successfully developed a tailored drug delivery system, emphasizing sustained QUER release and enhanced therapeutic effects. FMSNs, especially when coated with PDA, exhibit promising properties for efficient QUER delivery, providing a comprehensive approach that integrates advanced drug delivery technology and therapeutic efficacy.
Topics: Quercetin; Animals; 3T3-L1 Cells; Mice; Adipogenesis; Silicon Dioxide; Indoles; Nanoparticles; Delayed-Action Preparations; Drug Carriers; Polymers; Porosity; Drug Liberation; Cell Proliferation; Antioxidants
PubMed: 38868593
DOI: 10.2147/IJN.S463765 -
IMeta Feb 2024Pig gastrointestinal tracts harbor a heterogeneous and dynamic ecosystem populated with trillions of microbes, enhancing the ability of the host to harvest energy from...
Pig gastrointestinal tracts harbor a heterogeneous and dynamic ecosystem populated with trillions of microbes, enhancing the ability of the host to harvest energy from dietary carbohydrates and contributing to host adipogenesis and fatness. However, the microbial community structure and related mechanisms responsible for the differences between the fatty phenotypes and the lean phenotypes of the pigs remained to be comprehensively elucidated. Herein, we first found significant differences in microbial composition and potential functional capacity among different gut locations in Jinhua pigs with distinct fatness phenotypes. Second, we identified that Jinhua pigs with lower fatness exhibited higher levels of short-chain fatty acids in the colon, highlighting their enhanced carbohydrate fermentation capacity. Third, we explored the differences in expressed carbohydrate-active enzyme (CAZyme) in pigs, indicating their involvement in modulating fat storage. Notably, might be a representative bacterial species from Jinhua pigs with lower fatness, and a significantly higher percentage of its genome was dedicated to CAZyme glycoside hydrolase family 13 (GH13). Finally, a subsequent mouse intervention study substantiated the beneficial effects of isolated from experimental pigs, suggesting that it may possess characteristics that promote the utilization of carbohydrates and hinder fat accumulation. Remarkably, when Jinhua pigs were administered , similar alterations in the gut microbiome and host fatness traits were observed, further supporting the potential role of in modulating fatness. Taken together, our findings reveal previously overlooked links between and CAZyme function, providing insight into the basic mechanisms that connect gut microbiome functions to host fatness.
PubMed: 38868506
DOI: 10.1002/imt2.160 -
Cell Communication and Signaling : CCS Jun 2024Mesenchymal stem cells (MSCs) are widely used in the development of therapeutic tools in regenerative medicine. However, their quality decreases during in vitro...
BACKGROUND
Mesenchymal stem cells (MSCs) are widely used in the development of therapeutic tools in regenerative medicine. However, their quality decreases during in vitro expansion because of heterogeneity and acquired cellular senescence. We investigated the potential role of podoplanin (PDPN) in minimizing cellular senescence and maintaining the stemness of tonsil-derived MSCs (TMSCs).
METHODS
TMSCs were isolated from human tonsil tissues using an enzymatic method, expanded, and divided into two groups: early-passaged TMSCs, which were cultured for 3-7 passages, and late-passaged TMSCs, which were passaged more than 15 times. The TMSCs were evaluated for cellular senescence and MSC characteristics, and PDPN-positive and -negative cells were identified by fluorescence-activated cell sorting. In addition, MSC features were assessed in siRNA-mediated PDPN-depleted TMSCs.
RESULTS
TMSCs, when passaged more than 15 times and becoming senescent, exhibited reduced proliferative rates, telomere length, pluripotency marker (NANOG, OCT4, and SOX2) expression, and tri-lineage differentiation potential (adipogenesis, chondrogenesis, or osteogenesis) compared to cells passaged less than five times. Furthermore, PDPN protein levels significantly decreased in a passage-dependent manner. PDPN-positive cells maintained their stemness characteristics, such as MSC-specific surface antigen (CD14, CD34, CD45, CD73, CD90, and CD105) and pluripotency marker expression, and exhibited higher tri-lineage differentiation potential than PDPN-negative cells. SiRNA-mediated silencing of PDPN led to decreased cell-cycle progression, proliferation, and migration, indicating the significance of PDPN as a preliminary senescence-related factor. These reductions directly contributed to the induction of cellular senescence via p16/Rb pathway activation.
CONCLUSION
PDPN may serve as a novel biomarker to mitigate cellular senescence in the clinical application of MSCs.
Topics: Mesenchymal Stem Cells; Humans; Cellular Senescence; Membrane Glycoproteins; Cyclin-Dependent Kinase Inhibitor p16; Palatine Tonsil; Cell Differentiation; Cell Proliferation; Signal Transduction; Cells, Cultured
PubMed: 38867259
DOI: 10.1186/s12964-024-01705-8 -
Adipocyte Dec 2024Adipose tissue plays a crucial role in metabolic syndrome, autoimmune diseases, and many cancers. Because of adipose's role in so many aspects of human health, there is...
Adipose tissue plays a crucial role in metabolic syndrome, autoimmune diseases, and many cancers. Because of adipose's role in so many aspects of human health, there is a critical need for in vitro models that replicate adipose architecture and function. Traditional monolayer models, despite their convenience, are limited, showing heterogeneity and functional differences compared to 3D models. While monolayer cultures struggle with detachment and inefficient differentiation, healthy adipocytes in 3D culture accumulate large lipid droplets, secrete adiponectin, and produce low levels of inflammatory cytokines. The shift from monolayer models to more complex 3D models aims to better replicate the physiology of healthy adipose tissue in culture. This study introduces a simple and accessible protocol for generating adipose organoids using a scaffold-free spheroid model. The method, utilizing either 96-well spheroid plates or agarose micromolds, demonstrates increased throughput, uniformity, and ease of handling compared to previous techniques. This protocol allows for diverse applications, including drug testing, toxin screening, tissue engineering, and co-culturing. The choice between the two methods depends on the experimental goals, with the 96-well plate providing individualized control and the micromold offering scale advantages. The outlined protocol covers isolation, expansion, and characterization of stromal vascular fraction cells, followed by detailed steps for spheroid formation and optional downstream analyses.
Topics: Spheroids, Cellular; Adipose Tissue; Humans; Adipocytes; Cell Culture Techniques; Animals; Tissue Engineering; Cells, Cultured; Cell Differentiation; Mice
PubMed: 38864486
DOI: 10.1080/21623945.2024.2347215 -
Adipocyte Dec 2024Mouse mesenchymal stem cells (MSCs) provide a resourceful tool to study physiological and pathological aspects of adipogenesis. Bone marrow-derived MSCs (BM-MSCs) and...
INTRODUCTION AND PURPOSE
Mouse mesenchymal stem cells (MSCs) provide a resourceful tool to study physiological and pathological aspects of adipogenesis. Bone marrow-derived MSCs (BM-MSCs) and adipose tissue-derived MSCs (ASCs) are widely used for these studies. Since there is a wide spectrum of methods available, the purpose is to provide a focused hands-on procedural guide for isolation and characterization of murine BM-MSCs and ASCs and to effectively differentiate them into adipocytes.
METHODS AND RESULTS
Optimized harvesting procedures for murine BM-MSCs and ASCs are described and graphically documented. Since macrophages reside in bone-marrow and fat tissues and regulate the biological behaviour of BM-MSCs and ASCs, we included a procedure to deplete macrophages from the MSC preparations. The identity and stemness of BM-MSCs and ASCs were confirmed by flow cytometry using established markers. Since the composition and concentrations of adipogenic differentiation cocktails differ widely, we present a standardized four-component adipogenic cocktail, consisting of insulin, dexamethasone, 3-isobutyl-1-methylxanthine, and indomethacin to efficiently differentiate freshly isolated or frozen/thawed BM-MSCs and ASCs into adipocytes. We further included visualization and quantification protocols of the differentiated adipocytes.
CONCLUSION
This laboratory protocol was designed as a step-by-step procedure for harvesting murine BM-MSCs and ASCs and differentiating them into adipocytes.
Topics: Animals; Mesenchymal Stem Cells; Mice; Adipose Tissue; Adipogenesis; Macrophages; Bone Marrow Cells; Cell Differentiation; Cell Separation; Adipocytes; Cells, Cultured
PubMed: 38860452
DOI: 10.1080/21623945.2024.2350751 -
Frontiers in Endocrinology 2024The beneficial effect of thermogenic adipocytes in maintaining body weight and protecting against metabolic disorders has raised interest in understanding the regulatory...
BACKGROUND
The beneficial effect of thermogenic adipocytes in maintaining body weight and protecting against metabolic disorders has raised interest in understanding the regulatory mechanisms defining white and beige adipocyte identity. Although alternative splicing has been shown to propagate adipose browning signals in mice, this has yet to be thoroughly investigated in human adipocytes.
METHODS
We performed parallel white and beige adipogenic differentiation using primary adipose stem cells from 6 unrelated healthy subjects and assessed differential gene and isoform expression in mature adipocytes by RNA sequencing.
RESULTS
We find 777 exon junctions with robust differential usage between white and beige adipocytes in all 6 subjects, mapping to 562 genes. Importantly, only 10% of these differentially spliced genes are also differentially expressed, indicating that alternative splicing constitutes an additional layer of gene expression regulation during beige adipocyte differentiation. Functional classification of alternative isoforms points to a gain of function for key thermogenic transcription factors such as and , and enzymes such as , or . We find that a large majority of the splice variants arise from differential TSS usage, with beige-specific TSSs being enriched for PPARγ and MED1 binding compared to white-specific TSSs. Finally, we validate beige specific isoform expression at the protein level for two thermogenic regulators, PPARγ and PEMT.
DISCUSSION
These results suggest that differential isoform expression through alternative TSS usage is an important regulatory mechanism for human adipocyte thermogenic specification.
Topics: Humans; Adipocytes, Beige; Thermogenesis; Alternative Splicing; Protein Isoforms; Cell Differentiation; Adipogenesis; Male; Female; Adult; Cells, Cultured; Gene Expression Regulation; PPAR gamma
PubMed: 38859907
DOI: 10.3389/fendo.2024.1395750 -
Adipocyte Dec 2024microRNAs (miRNAs), a subclass of noncoding short RNAs, direct cells fate decisions that are important for cell proliferation and cell lineage decisions. Adipogenic...
microRNAs (miRNAs), a subclass of noncoding short RNAs, direct cells fate decisions that are important for cell proliferation and cell lineage decisions. Adipogenic differentiation contributes greatly to the development of white adipose tissue, involving of highly organized regulation by miRNAs. In the present study, we screened and identified 78 differently expressed miRNAs of porcine BMSCs during adipogenic differentiation. Of which, the role of miR-29c in regulating the proliferation and adipogenic differentiation was proved and detailed. Specifically, over-expression miR-29c inhibits the proliferation and adipogenic differentiation of BMSCs, which were reversed upon miR-29c inhibitor. Interference of inhibits the proliferation and adipogenic differentiation of BMSCs. Mechanistically, miR-29c regulates the proliferation and adipogenic differentiation of BMSCs by targeting IGF1 and further regulating the MAPK pathway and the PI3K-AKT-mTOR pathway, respectively. In conclusion, we highlight the important role of miR-29c in regulating proliferation and adipogenic differentiation of BMSCs.
Topics: Animals; Mesenchymal Stem Cells; MicroRNAs; Swine; Adipogenesis; Cell Proliferation; Cell Differentiation; Cells, Cultured; Signal Transduction; Adipocytes; Bone Marrow Cells
PubMed: 38858810
DOI: 10.1080/21623945.2024.2365211