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Oncocytic lipoadenoma is an extremely rare benign salivary gland tumor with only few cases reported in the literature. We herein report a case of oncocytic lipoadenoma originating in the parotid gland of a 65-year-old man. The tumor presented as a slowly growing asymptomatic right-sided parotid gland mass. On MRI, right parotid showed a 40 × 32 × 20 mm well-encapsulated, neoplastic mass in the superficial lobe. On core biopsy, differentials considered were nodular oncocytosis and oncocytoma. Subsequently, superficial parotidectomy was performed. The resected tumor was encapsulated, yellowish brown, and homogenous. Microscopically, it was composed of oncocytoma-like epithelial component admixed with mature adipocytes, each contributing to 50% of the mass. Adjacent salivary gland showed multiple foci of oncocytosis. Differential diagnosis includes lipomatous tumors as well as neoplastic and non-neoplastic oncocytic lesions of the salivary gland. The present case of oncocytic lipoadenoma against a background of multifocal oncocytic hyperplasia has been reported for its rarity.

Obesity has been associated with the development of 13 different types of cancers, including breast cancer. Evidence has indicated that cancer-associated adipocytes promote the proliferation, invasion, and metastasis of cancer. However, the mechanisms that link CAAs to the progression of obesity-related cancer are still unknown. Here, we found themature adipocytes in the visceral fat of HFD-fedmice have a CAAs phenotype but the stromal vascular fraction of the visceral fat has not. Importantly, we found the derivate of the potent PPARγ antagonist GW9662, BZ26 inhibited the reprogramming of mature adipocytes in the visceral fat of HFD-fed mice into CAA-like cells and inhibited the proliferation and invasion of obesity-related breast cancer. Further study found that itmediated the browning of visceral, subcutaneous and perirenal fat and attenuated inflammation of adipose tissue andmetabolic disorders. For the mechanism, we found that BZ26 bound and inhibited PPARγ by acting as a new modulator. Therefore, BZ26 serves as a novel modulator of PPARγ activity, that is, capable of inhibiting obesity-related breast cancer progression by inhibiting of CAA-like cell formation, suggesting that inhibiting the reprogramming of mature adipocytes into CAAs or CAA-like cells may be a potential therapeutic strategy for obesity-related cancer treatment. [ABSTRACT FROM AUTHOR]

White adipose tissue (WAT) plays a crucial role in energy homeostasis and secretes numerous adipokines with far-reaching effects. WAT is linked to diseases such as diabetes, cardiovascular disease, and cancer. There is a high demand for suitable in vitro models to study diseases and tissue metabolism. Most of these models are covered by 2D-monolayer cultures. This study aims to evaluate the performance of different WAT models to better derive potential applications. The stability of adipocyte characteristics in spheroids and two 3D gellan gum hydrogels with ex situ lobules and 2D-monolayer culture is analyzed. First, the differentiation to achieve adipocyte-like characteristics is determined. Second, to evaluate the maintenance of differentiated ASC-based models, an adipocyte-based model, and explants over 3 weeks, viability, intracellular lipid content, perilipin A expression, adipokine, and gene expression are analyzed. Several advantages are supported using each of the models. Including, but not limited to, the strong differentiation in 2D-monolayers, the self-assembling within spheroids, the long-term stability of the stem cell-containing hydrogels, and the mature phenotype within adipocyte-containing hydrogels and the lobules. This study highlights the advantages of 3D models due to their more in vivo-like behavior and provides an overview of the different adipose cell models., (© 2024 The Author(s). Macromolecular Bioscience published by Wiley‐VCH GmbH.)

Obesity and associated diseases, such as diabetes, have reached epidemic proportions globally. In this era of "diabesity", white adipose tissue (WAT) has become a target of high interest for therapeutic strategies. To gain insights into mechanisms of adipose (patho‐)physiology, researchers traditionally relied on animal models. Leveraging Organ‐on‐Chip technology, a microphysiological in vitro model of human WAT is introduced: a tailored microfluidic platform featuring vasculature‐like perfusion that integrates 3D tissues comprising all major WAT‐associated cellular components (mature adipocytes, organotypic endothelial barriers, stromovascular cells including adipose tissue macrophages) in an autologous manner and recapitulates pivotal WAT functions, such as energy storage and mobilization as well as endocrine and immunomodulatory activities. A precisely controllable bottom‐up approach enables the generation of a multitude of replicates per donor circumventing inter‐donor variability issues and paving the way for personalized medicine. Moreover, it allows to adjust the model's degree of complexity via a flexible mix‐and‐match approach. This WAT‐on‐Chip system constitutes the first human‐based, autologous, and immunocompetent in vitro adipose tissue model that recapitulates almost full tissue heterogeneity and can become a powerful tool for human‐relevant research in the field of metabolism and its associated diseases as well as for compound testing and personalized‐ and precision medicine applications. [ABSTRACT FROM AUTHOR]

Abstract Obesity and associated diseases, such as diabetes, have reached epidemic proportions globally. In this era of “diabesity”, white adipose tissue (WAT) has become a target of high interest for therapeutic strategies. To gain insights into mechanisms of adipose (patho‐)physiology, researchers traditionally relied on animal models. Leveraging Organ‐on‐Chip technology, a microphysiological in vitro model of human WAT is introduced: a tailored microfluidic platform featuring vasculature‐like perfusion that integrates 3D tissues comprising all major WAT‐associated cellular components (mature adipocytes, organotypic endothelial barriers, stromovascular cells including adipose tissue macrophages) in an autologous manner and recapitulates pivotal WAT functions, such as energy storage and mobilization as well as endocrine and immunomodulatory activities. A precisely controllable bottom‐up approach enables the generation of a multitude of replicates per donor circumventing inter‐donor variability issues and paving the way for personalized medicine. Moreover, it allows to adjust the model's degree of complexity via a flexible mix‐and‐match approach. This WAT‐on‐Chip system constitutes the first human‐based, autologous, and immunocompetent in vitro adipose tissue model that recapitulates almost full tissue heterogeneity and can become a powerful tool for human‐relevant research in the field of metabolism and its associated diseases as well as for compound testing and personalized‐ and precision medicine applications.

When normalized to volume, adipose tissue is comprised mainly of large lipid metabolizing and storing cells called adipocytes. Strikingly, the numerical representation of non-adipocytes, composed of a wide variety of cell types found in the so-called stromal vascular fraction (SVF), outnumber adipocytes by far. Besides its function in energy storage, adipose tissue has emerged as a versatile organ that regulates systemic metabolism and has therefore constituted an attractive target for the treatment of metabolic diseases. Recent high-resolution single cells/nucleus RNA seq data exemplify an intriguingly profound diversity of both adipocytes and SVF cells in all adipose depots, and the current data, while limited, demonstrate the significance of the intra-tissue cell composition in shaping the overall functionality of this tissue. Due to the complexity of adipose tissue, our understanding of the biological relevance of this heterogeneity and plasticity is fractional. Therefore, establishing atlases of adipose tissue cell heterogeneity is the first step towards generating an understanding of these functionalities. In this review, we will describe the current knowledge on adipose tissue cell composition and the heterogeneity of single-cell RNA sequencing, including the technical limitations. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer among women worldwide. Overweight and obesity are now recognized as established risk factors for this pathology in postmenopausal women. These conditions are also believed to be responsible for higher recurrence and mortality rates. Reciprocal interactions have been described between adipose and cancer cells. An adipose microenvironment favors a greater proliferation of cancer cells, their invasion and even resistance to anti-cancer treatments. In addition, the chronic low-grade inflammation observed in obese individuals is believed to amplify these processes. Among the cell types present in the breast, myoepithelial cells (MECs), located at the interface of the epithelial cells and the stroma, are considered “tumor suppressor” cells. During the transition from ductal carcinoma in situ to invasive cancer, disorganization or even the disappearance of MECs is observed, thereby enhancing the ability of the cancer cells to migrate. As the adipose microenvironment is now considered as a central actor in the progression of breast cancer, our objective was to evaluate if it could be involved in MEC functional modifications, leading to the transition of in situ to invasive carcinoma, particularly in obese patients. Through a co-culture model, we investigated the impact of human adipose stem cells from women of normal weight and obese women, differentiated or not into mature adipocytes, on the functionality of the MECs by measuring changes in viability, apoptosis, gene, and miRNA expressions. We found that adipose cells (precursors and differentiated adipocytes) could decrease the viability of the MECs, regardless of the original BMI. The adipose cells could also disrupt the expression of the genes involved in the maintenance of the extracellular matrix and to amplify the expression of leptin and inflammatory markers. miR-122-5p and miR-132-3p could also be considered as targets for adipose cells. The metabolite analyses revealed specific profiles that may be involved in the growth of neoplastic cells. All of these perturbations could thus be responsible for the loss of tumor suppressor status of MECs and promote the transition from in situ to invasive carcinoma.

Hair follicles (HFs) strongly interact with adipocytes within the dermal white adipose tissue (dWAT), suggesting a strong physiological dependence on the content of immature and mature adipocytes in this layer. This content is regulated by the proliferation and differentiation of adipocyte precursors, as well as by dedifferentiation of mature existing adipocytes. Spatially, long-range interactions between HFs and dWAT involve the exchange of extracellular vesicles which are differentially released by precursors, preadipocytes, and mature adipocytes. Different exogenous factors, including light irradiation, are likely to modify the release of adipocyte-derived exosomes in dWAT, which can lead to aberrations of the HF cycle. Consequently, dWAT should be considered as a potential target for the modulation of hair growth. Highlights HFs strongly interact with adipocytes within dWAT, suggesting a strong physiological dependence on the content of immature and mature adipocytes in this layer. This content is regulated by the proliferation and differentiation of adipose precursors and preadipocytes, as well as by dedifferentiation of mature existing adipocytes leading to the production of adipocyte-derived preadipocytes. Long-range spatial interactions between HFs and dermal adipocytes involve the exchange of extracellular vesicles which are differentially released by precursors, preadipocytes, and mature adipocytes, and are likely to carry various proteomic fingerprints during different phases of the HF cycle, effectively modulating the transcriptome profile of the recipient HFs. Different exogenous factors, including light irradiation and some chemical agents, can affect immature and immature adipocytes, and are likely to modify the release of adipocyte-derived exosomes in dWAT, which can lead to aberrations of the HF cycle. Dermal adipocytes should be considered as a potential target both for the modulation of hair growth and for the removal of unwanted hair. [ABSTRACT FROM AUTHOR]

The aryl hydrocarbon receptor (AhR) is a ligand-activated factor that regulates biological effects associated with obesity. The AhR agonists, such as environmental contaminants 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and β-naphthoflavone (BNF), inhibit preadipocyte differentiation and interfere with the functions of adipose tissue, whereas the antagonist may have opposite or protective effects in obesity. This study investigated the effects of α-naphthoflavone (α-NF), an AhR antagonist, on adipogenesis- and angiogenesis-associated factors in mature adipocytes and on cross-talk of mature adipocytes with endothelial cells (ECs). Besides, the roles of the AhR on lipid accumulation and on secretion of vascular endothelial growth factor were also determined by introducing siRNA of AhR. Differentiated 3T3-L1 cells were treated with α-naphthoflavone (α-NF) (1–5 μM) for 16 h. Lipid accumulation and the expressions of AhR-associated factors in the cells were determined. The interaction between adipocytes and ECs was investigated by cultivating ECs with conditioned medium (CM) from α-NF-treated mature adipocytes, followed by the determination of endothelial tube formation. The results showed that α-NF significantly increased triglyceride (TG) accumulation in mature adipocytes, which was associated with increased expression of hormone-sensitive lipase (HSL), estrogen receptor (ER), as well as decreased expression of AhR, AhR nuclear translocator (ARNT), cytochrome P4501B1 (CYP1B1), and nuclear factor erythroid-2-related factor (NRF-2) proteins. In addition, CM stimulated formation of tube-like structures in ECs, and α-NF further enhanced such stimulation in association with modulated the secretions of various angiogenic mediators by mature adipocytes. Similarly, increased TG accumulation and vascular endothelial growth factor (VEGF) secretion were observed in AhR-knockout cells. In conclusion, α-NF increased TG accumulation in mature adipocytes and enhanced mature adipocyte-stimulated tube formation in ECs, suggesting that the AhR may suppress obesity-induced adverse effects, and α-NF abolished the protective effects of the AhR.

Mature adipocytes are the major cell type in adipose tissue. This study aimed to explore the osteogenic potency of dedifferentiated fat cells obtained from osteoporotic patients (opDFATs) in vitro and in vivo. Mature adipocytes and adipose-derived stem cells (opASCs) were harvested from subcutaneous adipose tissue. Mature adipocytes were dedifferentiated to produce opDFATs by the ceiling culture method. OpDFATs were osteogenically induced in vitro with opASCs as a control. Cell growth, alkaline phosphatase (ALPase) activity and cell mineralization were determined, and expression levels of osteogenesis-specific genes (collagen I, osteocalcin and bone sialoprotein) were analyzed using quantitative reverse transcription polymerase chain reaction. After 14 days, the opDFATs were combined with a poly(lactide-co-glycolide)- ß-tricalcium phosphate porous scaffold after being suspended in collagen I gel and implanted into nude mice for 4 weeks prior to histological analysis. Unilocular lipid droplets in mature adipocytes gradually split into smaller droplets and disappeared from the cytoplasm. Mature adipocytes dedifferentiated to opDFATs and cell morphology changed from spherical to elongated. High levels of ALPase and cell mineralization were observed in opDFATs by staining. No significant differences were found between the growth curves, ALPase activity, cell mineralization and expression levels of osteogenesis-specific genes between opDFATS and opASCs. After implantation for 4 weeks, new bone tissue was observed histologically in the opDFATs-based biocomposite. OpDFATs are implicated as a novel type of seed cell for bone tissue engineering based on their osteogenic potency and higher abundance in adipose tissue compared with opASCs. [ABSTRACT FROM AUTHOR]

Purpose of Review: This review provides a summary of recent insights into the role of the local white adipose tissue (WAT) in systemic sclerosis. Recent Findings: Adipocytes located in an interfacial WAT area adjacent to fibrotic lesions have an intermediate phenotype and special properties implicated in fibrotic pathology in systemic sclerosis (SSc). The important role of these cells is recognized in different pathologies, such as wound healing, psoriasis, breast cancer, and prostate cancer. Additionally, both immature and mature adipocytes are involved in the appearance of fibroblast-like cells but exhibit different phenotypes and synthetic properties. Summary: Adipocytes from interfacial WAT adjacent to the fibrotic area in SSc are phenotypically different from bulk adipocytes and are involved in pathogenesis of SSc. Immature and mature adipocytes from this WAT layer differentiate into various types of fibroblast-like cells, making the local ratio of immature to mature adipocytes in interfacial WAT of particular importance in SSc pathogenesis. [ABSTRACT FROM AUTHOR]

Obesity has been associated with the development of 13 different types of cancers, including breast cancer. Evidence has indicated that cancer-associated adipocytes promote the proliferation, invasion, and metastasis of cancer. However, the mechanisms that link CAAs to the progression of obesity-related cancer are still unknown. Here, we found the mature adipocytes in the visceral fat of HFD-fed mice have a CAAs phenotype but the stromal vascular fraction of the visceral fat has not. Importantly, we found the derivate of the potent PPARγ antagonist GW9662, BZ26 inhibited the reprogramming of mature adipocytes in the visceral fat of HFD-fed mice into CAA-like cells and inhibited the proliferation and invasion of obesity-related breast cancer. Further study found that it mediated the browning of visceral, subcutaneous and perirenal fat and attenuated inflammation of adipose tissue and metabolic disorders. For the mechanism, we found that BZ26 bound and inhibited PPARγ by acting as a new modulator. Therefore, BZ26 serves as a novel modulator of PPARγ activity, that is, capable of inhibiting obesity-related breast cancer progression by inhibiting of CAA-like cell formation, suggesting that inhibiting the reprogramming of mature adipocytes into CAAs or CAA-like cells may be a potential therapeutic strategy for obesity-related cancer treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Geng, Yu, Zhou, Zheng, Fu, Kong and Feng.)

KCNMA1 is a pore-forming α-subunit of the large conductance Ca2+- and voltage-activated K+ channels, referred to as BK channels, which play key roles in various physiological functions. However, the role of KCNMA1 in mature adipocytes remains unclear. In this study, we reveal that kcnma1 expression is downregulated in white adipose tissue of mice fed a high-fat diet and in hypertrophied adipocytes. Furthermore, inhibition of kcnma1 expression or treatment with a BK channel blocker attenuated insulin-induced Akt phosphorylation in mature adipocytes. These results strongly indicate that KCNMA1 contributes to the regulation of insulin signalling in mature adipocytes. [ABSTRACT FROM AUTHOR]

Lipomlar, çoğunlukla ince bir fibröz kapsül ile çevrili olgunlaşmış adipositlerden oluşan benign mezenşimal neoplazmlardır. Lipomlar en yoğun olarak 40 yaş ve üzerinde görülür. Maksilofasiyal bölgede en sık yerleştiği kısım bukkal mukoza olarak bildirilmiştir. Bunu sırasıyla dil, ağız tabanı, dudaklar izler. Oral kavitede lipomların en sık görüldüğü bölgeler yanak, dil, damak, mandibulave dudaktır ve genellikle sapsız ya da kapsüllü bir kitle olarak gözlenirler. Bu olgu raporunda 6 aydır sağ alt vestibülde ağrısız şişliği bulunan, 58 yaşında erkek hasta sunulmuştur. Lezyon normal mukoza ile çevrili ve sınırlanmış olarak görülmekteydi. Hasta lokal anestezi altında opere edildi. Histopatolojik inceleme sonucunda lipom tanısı doğrulandı.

The composition of vascularized adipose tissue is still an ongoing challenge as no culture medium is available to supply adipocytes and endothelial cells appropriately. Endothelial cell medium is typically supplemented with epidermal growth factor (EGF) as well as hydrocortisone (HC). The effect of EGF on adipocytes is discussed controversially. Some studies say it inhibits adipocyte differentiation while others reported of improved adipocyte lipogenesis. HC is known to have lipolytic activities, which might result in mature adipocyte dedifferentiation. In this study, we evaluated the influence of EGF and HC on the co-culture of endothelial cells and mature adipocytes regarding their cell morphology and functionality. We showed in mono-culture that high levels of HC promoted dedifferentiation and proliferation of mature adipocytes, whereas EGF seemed to have no negative influence. Endothelial cells kept their typical cobblestone morphology and showed a proliferation rate comparable to the control independent of EGF and HC concentration. In co-culture, HC promoted dedifferentiation of mature adipocytes, which was shown by a higher glycerol release. EGF had no negative impact on adipocyte morphology. No negative impact on endothelial cell morphology and functionality could be seen with reduced EGF and HC supplementation in co-culture with mature adipocytes. Taken together, our results demonstrate that reduced levels of HC are needed for co-culturing mature adipocytes and endothelial cells. In co-culture, EGF had no influence on mature adipocytes. Therefore, for the composition of vascularized adipose tissue constructs, the media with low levels of HC and high or low levels of EGF can be used. [ABSTRACT FROM AUTHOR]

In vitro engineering of autologous fatty tissue constructs is still a major challenge for the treatment of congenital deformities, tumor resections or high-graded burns. In this study, we evaluated the suitability of photo-crosslinkable methacrylated gelatin (GM) and mature adipocytes as components for the composition of three-dimensional fatty tissue constructs. Cytocompatibility evaluations of the GM and the photoinitiator Lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) showed no cytotoxicity in the relevant range of concentrations. Matrix stiffness of cell-laden hydrogels was adjusted to native fatty tissue by tuning the degree of crosslinking and was shown to be comparable to that of native fatty tissue. Mature adipocytes were then cultured for 14 days within the GM resulting in a fatty tissue construct loaded with viable cells expressing cell markers perilipin A and laminin. This work demonstrates that mature adipocytes are a highly valuable cell source for the composition of fatty tissue equivalents in vitro. Photo-crosslinkable methacrylated gelatin is an excellent tissue scaffold and a promising bioink for new printing techniques due to its biocompatibility and tunable properties. [ABSTRACT FROM AUTHOR]

Engineering of large vascularized adipose tissue constructs is still a challenge for the treatment of extensive high-graded burns or the replacement of tissue after tumor removal. Communication between mature adipocytes and endothelial cells is important for homeostasis and the maintenance of adipose tissue mass but, to date, is mainly neglected in tissue engineering strategies. Thus, new co-culture strategies are needed to integrate adipocytes and endothelial cells successfully into a functional construct. This review focuses on the cross-talk of mature adipocytes and endothelial cells and considers their influence on fatty acid metabolism and vascular tone. In addition, the properties and challenges with regard to these two cell types for vascularized tissue engineering are highlighted. [ABSTRACT FROM AUTHOR]

Background aims: Adipose tissue is a critical organ that plays a major role in energy balance regulation and the immune response through intricate signals. Methods: We report on the inter-relation between mature adipocytes and lymphocytes in terms of adipocyte-derived T-cell chemo-attractants and adipocyte metabolic effects on lymphocytes. Results: During the culture time, mature adipocytes changed their structural and functional properties into de-differentiated cells. Isolated mature adipocytes expressed significantly higher levels of CIITA, major histocompatibility complex II (human leukocyte antigen [HLA]-DR) and costimulatory signal molecule CD80 compared with adipocytes after the de-differentiation process. Moreover, human leukocyte antigen--G, which may prevent the immune responses of mesenchymal stromal cells, was expressed at lower level in mature adipocytes compared with de-differentiated adipocytes. In line with these molecular data, functional results showed different immunoregulatory properties between adipocytes before and after the de-differentiation process. Mature adipocytes stimulated the proliferation of total lymphocytes and immunoselected cell populations CD3+, CD4+ and CD8+ in a direct contact-dependent way that involved the major histocompatibility complex I and II pathways. Moreover, adipocytes secreted potential chemo-attractant factors, but data showed that adipocyte-derived culture medium was not sufficient to activate lymphocyte proliferation, suggesting that a direct contact between adipocytes and immune cells was needed. However, specific mature adipocyte cytokines enhanced lymphocyte proliferation in a mixed lymphocyte reaction. Conclusions: In conclusion, cross-talk occurs between adipocytes and lymphocytes within adipose tissue involving T-cell chemo-attraction by mature adipocytes. Our findings, together with current observations in the field, provide a rationale to identify adipocyte-lymphocyte cross-talk that instigates adipose inflammation. [ABSTRACT FROM AUTHOR]

Background aims. Adipocytes are metabolically active cells and have endocrine functions, such as cytokine secretion. Notably, adipocytes are found underneath skin and are thought to be involved in the body's response to ischemia-reperfusion (I-R). I-R injury is an important factor in the pathogenesis of chronic skin wounds. In this study, we investigated the response of human adipocytes to hypoxia-reoxygenation (H-R), the in vitro equivalent of I-R. Methods. We cultured human mature adipocytes by enclosing them in hydrogel composed of hyaluronan and collagen and analyzed their proliferation and response to H-R. Results. The average diameter of mature adipocytes isolated from abdominal subcutaneous fat tissue was between 60 and 109 pm, and a positive correlation was found between adipocyte size and body mass index. Hydrogelenclosed human adipocytes displayed viability in in vitro culture and were capable of expressing foreign genes for at least 1 month. Proliferation analysis revealed 5-bromo-2'-deoxy-uridine labeling and positive Ki67 signaling, vascular endothelial growth factor expression was differentially altered in adipocytes in response to hypoxia and H-R. Adipocyte messenger RNA expression of pro-inflammatory cytokines, such as interleukin-1, interleukin-8 and tumor necrosis factor-a, was upregulated in response to H-R. In addition, the expression of heat shock protein 70, a cytoprotective gene, and inducible nitric oxide synthase, a proapoptotic gene, were both increased in H-R. Survival of hydrogel-enclosed adipocytes was found at 2 months after delivery into athymic mice. Conclusions. These and previous results from our group show that mature adipocytes can be cultured in vitro within a matrix and that they are functionally active cells that respond to environmental changes. [ABSTRACT FROM AUTHOR]

Lipomas are benign mesenchymal neoplasms composed of mature adipocytes, usually surrounded by a thin fibrous capsule. The most common location for lipomas in the maxillofacial region has been reported as the buccal mucosa and the peak incidence age for lipoma is 40 years and above. In the oral cavity, the most common sites are the cheek, tongue, palate, mandible and lip where lipomas occur as sessile or encapsulated masses. The present study reports a case of a 58-year-old man presented with a painless mass in the right vestibule that had been present for 6 months. The lesion was covered by normal mucosa, seemed to be circumscribed. Under local anesthesia, excision was performed. Histopathological examination was consistence with the diagnosis of a lipoma. Keywords: Lipoma, mature adipocytes, painless mass in vestibule. ÖZET Lipomlar, çoğunlukla ince bir fibröz kapsül ile çevrili olgunlaşmış adipositlerden oluşan benign mezenşimal neoplazmlardır. Lipomlar en yoğun olarak 40 yaş ve üzerinde görülür. Maksilofasiyal bölgede en sık yerleştiği kısım bukkal mukoza olarak bildirilmiştir. Bunu sırasıyla dil, ağız tabanı, dudaklar izler. Oral kavitede lipomların en sık görüldüğü bölgeler yanak, dil, damak, mandibula ve dudaktır ve genellikle sapsız ya da kapsüllü bir kitle olarak gözlenirler. Bu olgu raporunda 6 aydır sağ alt vestibülde ağrısız şişliği bulunan, 58 yaşında erkek hasta sunulmuştur. Lezyon normal mukoza ile çevrili ve sınırlanmış olarak görülmekteydi. Hasta lokal anestezi altında opere edildi. Histopatolojik inceleme sonucunda lipom tanısı doğrulandı.

Abstract: The dynamics of human and animal adipogenesis has been defined using several traditional cell systems including stromal vascular cells and adipocyte-related cell lines. But a relatively new cell system using progeny cells stemming from the dedifferentiation of purified cultures of mature adipocytes may be used for studying the development and biology of adipocytes. In this research, we show that isolated (and purified) mature adipocytes derived from Wagyu cattle dedifferentiate into progeny cells, and that these spindle-shaped, proliferative-competent daughter cells possess ability to proliferate. We outline the optimum cell culture system and offer precautionary thoughts for effective mature adipocyte culture. Collectively, this represents a novel cell model which may provide new insights into cell development, physiology and use as a model for animal production/composition, tissue engineering and disease treatment. [Copyright &y& Elsevier]

A large number of studies have shown that mature adipocytes are able to dedifferentiate in vitro into progeny cells, which possess proliferative capacity and mutilineage potential. Our present study confirms that mature adipocytes derived from Angus cattle also dedifferentiate into proliferative-competent progeny cells. However, this report is unlike any published for all other breeds of cattle we have worked with or that we have seen in published reports, in which mature adipocytes retain and distribute lipids into daughter cells symmetrically or asymmetrically. In the present work, we noted that Angus-derived mature adipocytes extruded a majority of their cellular lipid droplets prior to cell division. In this manner, these cells are processing lipid in a manner observed in mature adipocytes isolated from swine tissue. These results suggest that regulation of the mechanism(s) underlying lipid processing might be different between and within animal breeds. Lipid processing in beef-derived adipocytes during dedifferentiation may serve as a unique animal model for studying lipid metabolism during reverse adipogenesis. [ABSTRACT FROM AUTHOR]

Abstract: Weight gain and metabolic abnormalities are serious side effects associated with the use of several second generation antipsychotics (SGA). The adipose tissue has been considered a direct SGA target involved in the development of these adverse effects. Recent studies, mainly using murine cells, have suggested that SGA increase both adipogenesis of preadipocytes and lipid accumulation in mature adipocytes. However, to date there has been little research comparing the effects of antipsychotics with different propensities to induce weight gain on human in vitro models of white adipose tissue neoformation and metabolism. The present study aimed to investigate the effects of antipsychotics either strongly associated with weight gain, such as the SGA clozapine and olanzapine, or not, such as the SGA ziprasidone and the classical antipsychotic haloperidol, on proliferation and adipocyte differentiation of human adipose-derived stem cells (ADSCs) and lipogenesis in human mature adipocytes. Whereas ziprasidone induced elevated levels of cell death during adipogenesis and could not be investigated further, we observed that clozapine, olanzapine and haloperidol had slight stimulatory effects on the transcriptional program of ADSCs adipogenesis. However, the observed changes in adipocyte-specific genes were not accompanied by a significant increase in triglyceride accumulation within differentiated adipocytes. Our data also showed that these three antipsychotics displayed inhibitory effects on the proliferation rates of undifferentiated ADSCs. Regarding mature adipocyte metabolism, we observed that olanzapine slightly inhibited insulin-stimulated lipogenesis at the highest concentration used, and haloperidol exerted the strongest inhibitory effects on both basal and insulin-stimulated lipogenesis. Taken together, our results suggest that a direct and potent effect of clozapine and olanzapine on adipose tissue biology is not an important mechanism by which these SGA induce metabolic disturbances in humans. On the other hand, the haloperidol-mediated downregulation of the lipogenic capacity of human adipose tissue may be a possible mechanism contributing to its lower propensity to induce serious metabolic side effects. [Copyright &y& Elsevier]

Background: Adipose tissue engineering has been hampered by the inability to culture mature adipocytes. Adipose-derived stem cell (ASC) culture opens the way for the preparation of human 3-D hypodermis in large quantities. These models play a role in obesity-related active molecules and slimming agent screening. Moreover, they contribute to a better understanding of the mechanisms underpinning obesity. Materials and Methods: Freshly extracted ASC from fat tissue were characterized by flow cytometry for CD73, CD90, CD105, HLA-ABC, CD14 and CD45 markers and by Western blot for pref-1. Their differentiation in mature adipocytes was followed by lipid and adiponectin secretion or by oil red O staining and radioimmunoassay. Neosynthesized extracellular matrix (ECM) of 3-D hypodermis was investigated by immunohistochemistry (collagen type I, V and VI) and transmission electron microscopy. Results: Our results demonstrate that the culture of preadipocytes in proliferation medium for 15 days followed by 16 days of culture in differentiation medium allowed production of the thickest single-layer hypodermis in which preadipocytes and mature adipocytes coexist and synthesize adiponectin and ECM components. Functionality of our 3-D single-layer hypodermis was demonstrated both by a 3.5-fold glycerol production after its stimulation with norepinephrine (adrenergic agonist) and by its slimming after caffeine treatment versus the nontreated 3-D hypodermis. Conclusion: This economic 3-D model, easy to prepare and giving reproducible results after the treatment of actives, is useful for pharmacotoxicological trials as an alternative to animal experimentation. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]