Layer Of Adipose Tissue Research Articles

Analysis of Physiological Oxygen Concentrations in Different Abdominal Fat Layers by Body Mass Index.

Physiological oxygen concentration in adipose tissue is closely linked to metabolic disorders such as chronic inflammation and insulin resistance. However, the nature of the variation in the oxygen levels of adipose tissue with body mass index (BMI) and depths of abdominal fat remain unclear. Therefore, this study aimed to elucidate the patterns of oxygen concentration in adipose tissue layers according to BMI. In this study, patients undergoing abdominal fat removal surgery were divided into the normal-weight (NW) or overweight-obese (OW) groups based on their BMI. Oxygen concentrations in abdominal superficial (sSAT) and deep subcutaneous adipose tissue (dSAT) were measured. The oxygen consumption rate, mean cell area, and capillary density in both tissue layers were compared between the two groups. Furthermore, the interaction between these three variables, BMI, and adipose tissue oxygen concentration, was analyzed using linear regression. A total of 42 patients were recruited in this study and we observed that oxygen concentration in the sSAT was significantly lower than in the dSAT, irrespective of BMI. In terms of the oxygen concentration in the dSAT, OW's was significantly lower than that of NW's. Linear regression analysis revealed a significant correlation between dSAT oxygen concentration and BMI, mean adipocyte area, and vascular density. Individuals who are obese have significantly lower oxygen levels in the deep abdominal adipose tissue, and this is influenced by BMI, adipocyte area, and capillary density. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Association of vasospastic angina with myocardial bridging and pericoronary adipose tissue attenuation on computed tomography angiography

Abstract Background Recent studies have suggested that vasospastic angina (VSA) is associated with myocardial bridging (MB). The relationship between VSA and pericoronary adipose tissue (PCAT) inflammation has also been reported but still remains to be determined. Purpose We investigated clinical and coronary computed tomography angiographic (CCTA) features in patients with VSA diagnosed by spasm provocation test (SPT). Methods We retrospectively studied patients with clinically suspected VSA who underwent both SPT with intracoronary acetylcholine administration and CCTA within three months before SPT at Tsuchiura Kyodo General Hospital. PCAT inflammation was evaluated on CCTA images by fat attenuation index (FAI) which has been recently used as a novel biomarker of coronary inflammation. In FAI analysis, we measured FAI of the proximal segments not only for 4mm (FAI4mm) but also for the inner and thinner 2mm pericoronary adipose tissue layer from the vessel wall (FAI2mm), since FAI2mm has been reported to provide better discriminating efficacy for VSA diagnosis than FAI4mm. We also evaluated the presence or absence of MB and its features including length, depth and location on CCTA images. Results A total of 172 patients were studied and VSA was diagnosed in 39.0% (67/172) of patients by SPT according to the latest guideline. Male (74.6% vs 49.5%, P=0.001), smoking history (74.6% vs 48.6%, P=0.001) were more frequent, and prevalence of CCTA-defined MB (47.8% vs 34.3%, P=0.082) and RCA-FAI2mm (-68.73 HU vs -73.35 HU, P<0.001) were higher in patients with versus without VSA. In multivariable analysis, presence of CCTA-defined MB (odds ratio [OR] 2.56, 95% confidence interval [CI] 1.26-5.19, P=0.0095), RCA-FAI2mm (OR 1.05, 95% CI 1.01-1.09, P=0.025), and smoking (OR 3.40, 95% CI 1.57-7.36, P=0.0019) were independently associated with VSA. A combination of high RCA-FAI2mm (≥-68.93HU, the best cut-off obtained by ROC analysis with AUC of 0.64, 95% CI 0.551 - 0.728), smoking history and existence of MB could predict VSA with 73.7% of probability, while an absence of all 3 covariates could exclude VSA with 85.3% of probability. Conclusion CCTA-defined MB, high RCA-FAI2mm and smoking were independently predictive of VSA.

Vasa vasorum of the no-touch saphenous vein graft observed using frequency-domain optical coherence tomography.

One possible reason for the long-term patency of no-touch saphenous vein grafts is the preservation of the vasa vasorum in the adventitia/perivascular adipose tissue. In this study, we investigated the vasa vasorum of the no-touch saphenous vein graft in vivo using frequency-domain optical coherence tomography, performed qualitative and quantitative analyses, and compared them with the conventional saphenous vein graft. A frequency-domain optical coherence tomography study was performed on 14 saphenous vein grafts at the postoperative coronary angiography 1-2 weeks after surgery (no-touch group, n = 9; conventional group, n = 5). Many signal-poor tubular lumen structures that can be recognised in the cross-sectional and longitudinal profiles, which indicates the vasa vasorum, were observed in the adventitial/perivascular adipose tissue layer in the no-touch saphenous vein grafts. In contrast, the vasa vasorum was less abundant in the conventional saphenous vein grafts. The vasa vasorum volume per millimetre of graft in the no- touch group was significantly higher than in the conventional group (0.0020 [0.0017, 0.0043] mm3 and 0.0003 [0.0000, 0.0006] mm3, P = 0.023). Frequency-domain optical coherence tomography showed abundant vasa vasorum in the thick adventitia/perivascular adipose tissue layer of no-touch saphenous veins in vivo. In contrast, few vasa vasorum was observed in the conventional saphenous vein grafts.

Decellularized adipose-derived matrix from Superficial layers of abdominal adipose tissue exhibits superior capacity of adipogenesis compared to deep layers

The adipogenic property of decellularized adipose-derived matrix (DAM) varies widely across reports, making it difficult to make a horizontal comparison between reports and posing challenges for the stable clinical translation of DAM. It is possibly due to differences in donor characteristics, but the exact relationship remains unclear. Despite extensive research on the differences between superficial and deep layers of abdominal subcutaneous fat, a main donor of DAM, little is known about their extracellular matrix (ECM) which is promising in regenerative medicine. In this study, we first confirmed the distinct compositional profiles and adipogenic potential between superficial and deep DAM (S-DAM and D-DAM). Both in vitro and in vivo assays confirmed superior adipogenic induction potential in S-DAM over D-DAM. Total amounts of ECM proteins like collagen and laminin were similar, however, the predominant types differed, with collagen I dominating S-DAM and collagen XIV prevailing in D-DAM. S-DAM was enriched with mitochondrial and immunological proteins, whereas D-DAM featured more neuronal, vascular, muscular, and endocrine-related proteins. More proteins involved in mRNA processing were found in D-DAM, with Protein-Protein Interaction (PPI) analysis revealing HNRNPA2B1, HNRNPA1, and HNRNPC as the most tightly interacting members. These findings not only deepen our comprehension of the structural and functional heterogeneity of adipose tissues but also become one of the reason for the large variability between batches of DAM products, providing guidance for constructing more efficient and stable bio-scaffolds.

Choke Anastomosis: A Key Element Acting as a Shunt Converter Between Adjacent Angiosomes.

Choke anastomosis is commonly recognized as a resistance factor that detrimentally affects the hemodynamics of the skin flap; however, its additional potential physiological roles in normal skin function are currently not fully understood. Ten cadaveric forehead flap specimens pedicled with unilateral STAs were perfused with lead oxide-gelatin mixture, and then dissected into 3 layers, including the super temporal fascia-frontalis-galea aponeurotica layer, the subcutaneous adipose tissue layer, and the "super-thin flap" layer. The forehead flap and stratified specimens underwent molybdenum target x-ray and subsequent transparent processing to effectively visualize the microscopic spatial architecture of arterial vessels across all levels. Based on the different anastomoses near the midline area of the flap, 2 types of arterial perfusion were identified: choke anastomosis type (8/10) and true anastomosis type (2/10). The former formed multiple choke anastomoses near the midline. In the "super-thin flap" layer, arterial perfusion density on the ipsilateral side was significantly higher compared to that on the contralateral side. The arterioles on the ipsilateral side exhibited a dense and uninterrupted distribution, whereas those on the contralateral side appeared sparse and dispersed. The latter exhibited an alternative perfusion pattern; the bilateral arterial vessels were connected with 3 to 5 true anastomoses near the midline. Furthermore, the microscopic architecture confirmed a uniform distribution of arterioles that remained continuous from ipsilateral to contralateral sides in the "super-thin flap" layer. This study demonstrated that choke anastomosis not only impairs blood perfusion in the adjacent angiosomes but also acts as a shunt converter to impact the blood supply of distal skin flaps at different levels through the "trans-territory diversion phenomenon." This results in necrosis of the superficial dermis while preserving survival of the deep subcutaneous adipose tissue.

GelMA loaded with platelet lysate promotes skin regeneration and angiogenesis in pressure ulcers by activating STAT3

Pressure ulcers (PU) are caused by persistent long-term pressure, which compromises the integrity of the epidermis, dermis, and subcutaneous adipose tissue layer by layer, making it difficult to heal. Platelet products such as platelet lysate (PL) can promote tissue regeneration by secreting numerous growth factors based on clinical studies on skin wound healing. However, the components of PL are difficult to retain in wounds. Gelatin methacrylate (GelMA) is a photopolymerizable hydrogel that has lately emerged as a promising material for tissue engineering and regenerative medicine. The PL liquid was extracted, flow cytometrically detected for CD41a markers, and evenly dispersed in the GelMA hydrogel to produce a surplus growth factor hydrogel system (PL@GM). The microstructure of the hydrogel system was observed under a scanning electron microscope, and its sustained release efficiency and biological safety were tested in vitro. Cell viability and migration of human dermal fibroblasts, and tube formation assays of human umbilical vein endothelial cells were applied to evaluate the ability of PL to promote wound healing and regeneration in vitro. Real-time polymerase chain reaction (PCR) and western blot analyses were performed to elucidate the skin regeneration mechanism of PL. We verified PL’s therapeutic effectiveness and histological analysis on the PU model. PL promoted cell viability, migration, wound healing and angiogenesis in vitro. Real-time PCR and western blot indicated PL suppressed inflammation and promoted collagen I synthesis by activating STAT3. PL@GM hydrogel system demonstrated optimal biocompatibility and favorable effects on essential cells for wound healing. PL@GM also significantly stimulated PU healing, skin regeneration, and the formation of subcutaneous collagen and blood vessels. PL@GM could accelerate PU healing by promoting fibroblasts to migrate and secrete collagen and endothelial cells to vascularize. PL@GM promises to be an effective and convenient treatment modality for PU, like chronic wound treatment.

Method for obtaining ecological products from rainbow trout Oncorhynchus mykiss farming

In aquaculture, the period of active development of aquatic organisms is considered one of the most important for the formation of potential in the future. The issue of using natural components when growing aquatic organisms and feeding young fish is given special attention. This research investigated Spirulina (25%) + Vermiculture (50%) + Hermetia illucens (25%) as an additional source of functional active substances and protein that affect the body performance of rainbow trout in early ontogenesis. All objects were cultured in a special bioreactor, which was a component of the recirculating aquaculture model system as well as in the laboratory, where an installation was made for cultivating natural food. The results of the scientific and practical part of the work showed that after the end of the experiment, body weight was higher in the experimental fish by 7.2% than in the control group. This article presents the results of feeding rainbow trout as one of the cases of improving the morpho-functional and biochemical composition of the blood of this species: an increase in the total number of red blood cells by 11.0%, hemoglobin content by 9.7%, total protein at 22.7%, albumin by 24.2%, and creatinine by 15.5%, compared with the control group. The presented positive changes in the functional status of the rainbow trout organism were in harmony with the parameters of body weight, as well as histological indicators. Histological indicators of the liver and muscle tissue of the fish supplemented the obtained positive result of the influence of natural and active components of the feed. Feeding fish according to the scheme in the experimental group promotes the formation of layers of special adipose tissue in the endomysium. The total amount of the stromal component in the muscle tissue of rainbow trout was 25% of the mass of the entire tissue. The control group showed that the muscle fibers were polygonal in cross section, separated from each other within the bundle by delicate layers of endomysium. When using a standard feeding regimen (control group), the stromal component is a moderately expanding structure that replaces the space between the fibers. The experimental group had the most significant indicators. The intensification of individual aspects of homeostasis achieved with the help of feed components (experimental group) promotes the growth of muscle fibers in thickness due to the formation of new fibrils, but not an increase in the proportion of sarcoplasm (watery meat). As a result, neurohumoral regulation and substance synthesis processes improved in the fishes’ body, which helps to improve ontogenesis rates. The presented ingredients in the diet of rainbow trout are natural stimulants of metabolic processes and sources of nutrients. The method allows aquaculture to be defined as being as close as possible to “environmentally safe”. The next stage will be a comprehensive analysis of the qualitative and quantitative characteristics of rainbow trout meat under the influence of the feed factor.

Ventricular Epicardial Adipose Distribution on Human Hearts: 3-Dimensional Reconstructions and Quantitative Assessments.

Epicardial interventions have forged new frontiers in cardiac ablation and device therapies. Healthy human hearts typically present with significant adipose tissue layers superficial to the ventricular myocardium and may hinder success or increase the complexities of epicardial interventions. We quantitatively evaluated the distribution of epicardial adipose tissue on the surface of human hearts and provided high-fidelity 3-dimensional reconstructions of these epicardial adipose tissue layers. The regional thickness of adipose tissues was analyzed at 51 anatomical reference points surrounding both ventricles and compared to specific patient demographics. Adipose deposits on the human hearts displayed characteristic patterns, with the thickest accumulations along the interventricular septa (anterior, 9.01 ± 0.50mm; posterior, 6.78 ± 0.50mm) and the right ventricular margin (7.44 ± 0.57mm). We provide one of the most complete characterizations of human epicardial adipose location and relative layer thickness. These results are considered fundamental for an underlying anatomic understanding when performing procedures within the pericardial space.

Thickened submucosal adipose tissue layer during endoscopic submucosal dissection of inflammatory bowel disease dysplasia

Thickened submucosal adipose tissue layer during endoscopic submucosal dissection of inflammatory bowel disease dysplasia

Abstract 6810: Macrophage secreted CCL9/CCL5 induces CCR1-mediated ovarian cancer metastasis to the omentum in the absence of CCL6

Abstract The tumor-microenvironment (TME) of the omentum plays an important role in providing a pre-metastatic niche for high-grade serous ovarian cancer (HGSC-OvCa) progression. Omentum, a layer of fatty adipose tissue within the peritoneal cavity, is the preferred primary metastatic site for OvCa. Omentum is a well-vascularized fatty tissue containing wide-spread immune clusters (milky spots). Milky spots in the omentum are primarily composed of B cells, T cells, macrophages, NK cells, and dendritic cells. Previous studies from our laboratory have highlighted the importance of CCL6 secreted by omental macrophages as a key chemokine in providing a pre-metastatic niche by activating the CCR1 axis on the cancer cells required for OvCa invasion. We engineered and characterized a CCL6-depleted in vivo mouse model using CRISPR/Cas9 to study the effect on OvCa progression and macrophage biology. We demonstrate that deletion of CCL6 in mice alters characteristics of omental tissue-resident (OM-Macφ) and bone marrow-derived macrophages (BMDM) derived from circulating monocytes. RNA sequencing of OM-Macφ and microarray study of BMDM revealed that CCL6 deletion produces enhanced TGFβ1+CSF-1+CCL5+ expression in OM-Macφ and an increase in TGFβ1+CSF-1+CCL9+ in BMDM. This acts as a rescue mechanism to maintain activation of their shared CCR1 receptor with a pro-M2 stimulation profile. Deep multiplexed imaging of the omentum tissue by CODEX showed that CCL6 deletion alters the architecture of milky spots, with enriched macrophage content and reduced B-cell and T-cell-rich neighborhoods. While our previous studies indicated that CCL6 deletion could potentially have an anti-tumoral effect, we found that it does not significantly affect murine ID8 ovarian cancer tumor burden in both short-term (7 days) and long-term in vivo studies and provides no added survival advantage. We report that CCL9+F4/80+ macrophages accumulate in the omentum post-tumor infiltration in the CCL6-KO model, and neutralizing CCL9 in the CCL6-KO BMDM macrophage-derived conditioned media significantly reduces migration of ID8 cancer cells in vitro. Furthermore, we demonstrate that murine CCL9 and its analog, human CCL15, promote the epithelial-mesenchymal transition (EMT) of mouse ID8 and human A2780 OvCa cells. Moreover, our findings indicate that human CCL15 is a prognostic biomarker for reduced survival in OvCa patient cohorts (Stages I&II and Stage III&IV). Further classification of HGSC-OV patients (n=375) from TCGA-OV based on CCL15 and CCR1-high expression correlated with a higher expression of TGFβ1, CCL5, and a T-cell exhaustion signature in the TME. Taken together, given the apparent redundancy of the chemokine network controlling CCR1 signaling, our findings support the strategy of therapeutically blocking the CCR1 receptor to potentially produce a favorable anti-tumor response in HGSC-OvCa patients. Citation Format: Supreeti Tallapragada, Justine Chan, Venkatesh Krishnan, Oliver Dorigo. Macrophage secreted CCL9/CCL5 induces CCR1-mediated ovarian cancer metastasis to the omentum in the absence of CCL6 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6810.

Omentum a Powerful Viable Organ in Patient with Liver Crash Trauma: A Case Series

The Omentum is a large flat adipose tissue layer nestling on the surface of the intra-peritoneal organs. Besides fat storage, omentum has key biological functions in immune-regulation and tissue regeneration. Omentum biological properties include neovascularization, haemostasis, tissue healing and regeneration and as an in vivo incubator for cells and tissue cultivation. Some of these properties have long been noted in surgical practice and used empirically in several procedures. we did 5 pedicular omental flap in 5 patients to prepare hemostasis in trauma with liver crash after resection and repairs.

Microstructural analysis of meat and internal organs of broiler chickens using a probiotic biological product

Probiotic preparation containing bacteria of the genus Bacillus subtilis and Bacillus licheniformis used for feeding broiler chickens to improve feed digestion, nutrient absorption, increase immune status and productivity, and for the prevention and treatment of various poultry diseases. The purpose of the study is to conduct histological tests of broiler chicken slaughter products when they were administered a probiotic biologic medical product in doses of: 0.5 g, 2.0, and 4.0 g per 10 dm3 of water. The material was examined by the histological method. It was found that the muscle fibres in the pectoralis major are of the same type, evenly directed, the cytoplasm of muscle fibres is moderately eosinophilic, uniformly light pink, and minor layers of adipose tissue are found between the bundles of muscle fibres. The morphological architectonics of the heart muscle are preserved, cardiomyocytes are homogeneous and have a clear orientation. The microstructure of the liver of broiler chickens is unchanged: hepatocytes are collected in the same type of groups; the central veins are desolate; the cytoplasm of these cells is homogeneous, clear, and pink; the nuclei are weakly basophilic. In the spleen, the follicular structure is formed, leukocytes are diffusely placed at different stages of differentiation; vessels in significant numbers, thickened, of different calibre. The cuticle of the muscular part of the stomach contains the epithelial layer, the volume part of the connective tissue base layer is revealed; muscle fibres are located under the mesenchymal base of the cuticle. Lungs by morphological structure have bronchial tubes throughout the structure, which contain blood cells. According to the results of the conducted studies, a beneficial effect of a probiotic biological product at a dose of 4.0 g/10 dm3 of water on the morphology of the pectoralis major and internal organs of broiler chickens was established. Therefore, a probiotic at a dose of 4.0 g/10 dm3 of water during the drinking of broiler chickens can be recommended to increase productivity and produce safe slaughter products. The practical significance of the results obtained is to determine the features of the effect of feeding poultry with different doses of probiotics on the microstructure of its slaughter products, which is important for obtaining the best effect from its use

Patient Age and Gender Analysis of Oral and Maxillofacial Clinical Conditions in Iraq: A Retrospective Study

Background This study aims at assessing the age and gender distribution among patients with various clinical conditions who sought treatment at the Department of Oral and Cranio-maxillofacial Surgery in Al Kindy Teaching Hospital in Baghdad, Iraq. Methods The research data for this study was obtained from the Department of Oral and Cranio-maxillofacial Surgery at Al Kindy Teaching Hospital in Baghdad, Iraq. The data was collected between April 2019 and February 2020, involving 1443 patients spanning various age groups, from infants to 85-year-olds. The patients are categorized based on age, sex, and diagnosis using the International Classification of Diseases. The diagnosed diseases were classified according to the Contemporary Oral and Maxillofacial Surgery textbook guidelines. Results The majority of patients are in their second decades, and most of the samples that attended the hospital are from the male category, female patients had to do with temporomandibular problems, trauma, and surgical extraction. In contrast, the most common category among male patients is trauma, followed by jaw fractures. Trauma, Follow-up, Facial Palsy, Ranula, Trigeminal Neuralgia, and Parotid Gland Swelling were all significantly different between males and females when compared on their own in each category. Conclusions Males exhibit a higher hospital attendance rate compared to females, with males being more prone to oral trauma, while females are more susceptible to temporomandibular joint disorders. Young children have a greater likelihood of experiencing trauma rather than jaw fractures due to the presence of a thicker adipose tissue layer and the absence of paranasal sinus pneumatization.

Parameter variation effects on millimeter wave dosimetry based on precise skin thickness in real rats

This study presents a parametric analysis of the steady-state temperature elevation in rat skin models due to millimeter wave exposure at frequencies from 6–100 GHz. The statistical data of the thickness of skin layers, namely epidermis, dermis, dermal white adipose tissue, and panniculus carnosus, were measured for the first time using the excised tissues of real male Sprague–Dawley rats. Based on the precise structure obtained from the histological analysis of rat skin, we solve the bioheat transfer equation to investigate the effects of changes in parameters, such as body parts and thermal constants, on the absorbed power density and temperature elevation of biological tissues. Owing to the notably thin dermal white adipose tissue layer, the surface temperature elevation in the rat head and dorsal skin at 6–100 GHz is 52.6–32.3% and 83.3–58.8% of the average values of different human skin models, respectively. Our results also reveal that the surface temperature elevation of rat skin may correlate with the tissue thickness and deep blood perfusion rates.

Application of upconversion nanoparticles as a thermal sensor for biological tissue

The paper shows the possibility of simultaneous registration of the temperature of nanoparticles embedded in the fat layer and temperature-induced phase transitions in the fat layer. The luminescence spectra of upconversion particles (UCNPs) were measured and analyzed in a wide temperature range: from room to physiological and further to a hyperthermic temperature resulting in tissue morphology change. Typical samples thickness of adipose tissue was 0.5 mm. The sample temperature varied between 25 °C and 60 °C. The temperature dependence of the UCNPs luminescence intensity from UCNPs deposited onto the sample surface (1 layer) and from UCNPs deposited between two layers of abdominal adipose tissue was recorded. In the course of adipocyte heating, lipids of fat droplet first transit from a crystalline form to a liquid crystal form and then to a liquid form, which is characterized by much less scattering. The high-temperature transition is recorded most well. The obtained results confirm a high sensitivity of the luminescent UCNPs to the temperature variations within tissues and show a strong potential for the controllable tissue thermolysis.

Combining Allograft Adipose and Fascia Matrix as an Off-the-Shelf Scaffold for Adipose Tissue Engineering Stimulates Angiogenic Responses and Activates a Proregenerative Macrophage Profile in a Rodent Model.

Bioscaffolds for treating soft tissue defects have limitations. As a bioscaffold, allograft adipose matrix (AAM) is a promising approach to treat soft tissue defects. Previously, we revealed that combining superficial adipose fascia matrix with AAM, components of the hypodermis layer of adipose tissue, improved volume retention, adipogenesis, and angiogenesis in rats 8 weeks after it was implanted compared with AAM alone. Here, we modified the fascia matrix and AAM preparation, examined the tissue over 18 weeks, and conducted a deeper molecular investigation. We hypothesized that the combined matrices created a better scaffold by triggering angiogenesis and proregenerative signals. Human AAM and fascia matrix were implanted (4 [1 mL] implants/animal) into the dorsum of male Fischer rats (6-8 weeks old; ~140 g) randomly as follows: AAM, fascia, 75/25 (AAM/fascia), 50/50, and 50/50 + hyaluronic acid (HA; to improve extrudability) (n = 4/group/time point). After 72 hours, as well as 1, 3, 6, 9, 12, and 18 weeks, graft retention was assessed by a gas pycnometer. Adipogenesis (HE), angiogenesis (CD31), and macrophage infiltration (CD80 and CD163) were evaluated histologically at all time points. The adipose area and M1/M2 macrophage ratio were determined using ImageJ. RNA sequencing (RNA-seq) and bioinformatics were conducted to evaluate pathway enrichments. By 18 weeks, the adipose area was 2365% greater for 50/50 HA (281.6 ± 21.6) than AAM (11.4 ± 0.9) (P < 0.001). The M1/M2 macrophage ratio was significantly lower for 50/50 HA (0.8 ± 0.1) than AAM (0.9 ± 0.1) at 6 weeks (16%; P < 0.05). This inversely correlated with adipose area (r = -0.6; P > 0.05). The RNA-seq data revealed that upregulated adipogenesis, angiogenesis, and macrophage-induced tissue regeneration genes were temporally different between the groups. Combining the fascia matrix with AAM creates a bioscaffold with an improved retention volume that supports M2 macrophage-mediated angiogenesis and adipogenesis. This bioscaffold is worthy of further investigation.

Specific Features of Stromal Cells Isolated from the Two Layers of Subcutaneous Adipose Tissue: Roles of Their Secretion on Angiogenesis and Neurogenesis.

Human-adipose-tissue-derived mesenchymal stromal cells (AD-MSCs) are currently being tested as autologous-cell-based therapies for use in tissue healing and regeneration. Recent studies have also demonstrated that AD-MSC-derived exosomes contribute to tissue repair and peripheral nerve regeneration. Subcutaneous abdominal adipose tissue (AAT) is divided into two layers: the superficial layer (sAAT) and the deep layer (dAAT). However, it is unclear whether there are particular characteristics of each layer in terms of AD-MSC regenerative potential. Using AD-MSCs purified and characterized from three abdominoplasties, we compared their secretomes and exosome functions to identify which layer may be most suitable as a source for cell therapy. Phenotypical analysis of the AD-MSCs containing stromal vascular fraction did not reveal any difference between the two layers. The AD-MSC secretomes showed a very similar pattern of cytokine content and both layers were able to release exosomes with identical characteristics. However, compared to the secretome, the released exosomes showed better biological properties. Interestingly, dAAT exosomes appeared to be more effective on neuromodulation, whereas neither sAAT nor dAAT-derived exosomes had significant effects on endothelial function. It thus appears that AD-MSC-derived exosomes from the two abdominal adipose tissue layers possess different features for cell therapy.

Tracing the Change and Contribution of Subcutaneous Adipose to Skin Expansion Using a Luciferase-Transgenic Fat Transplantation Model.

During skin expansion, subcutaneous adipose tissue undergoes the greatest change. The adipose layer appears to gradually thin or even disappear in long-term expansion. The response and contribution of adipose tissue to skin expansion remain to be elucidated. The authors established a novel expansion model by transplanting luciferase-transgenic adipose tissue into the rat dorsum, followed by integrated expansion, to trace the dynamic changes in subcutaneous adipose tissue during expansion and the migration of adipose tissue-derived cells. In vivo luminescent imaging was performed to continuously track the adipose tissue changes. Histologic analysis and immunohistochemical staining evaluated the regeneration and vascularization of the expanded skin. Growth factor expression in expanded skin with or without adipose tissue was determined to evaluate the paracrine effect of adipose tissue. Adipose tissue-derived cells were traced in vitro by anti-luciferase staining, and their fate was determined by costaining for PDGFRα, DLK1, and CD31. In vivo bioimaging showed that cells in adipose tissue were alive during expansion. After expansion, the adipose tissue exhibited fibrotic-like structures, with more DLK1 + preadipocytes. Skin expanded with adipose tissue was significantly thicker than that without adipose tissue, with more blood vessels and cell proliferation. Vascular endothelial growth factor, epidermal growth factor, and basic fibroblast growth factor expression was higher in adipose tissue than in skin, indicating paracrine support from adipose tissue. Luciferase-positive adipose tissue-derived cells were observed in expanded skin, indicating direct participation in skin regeneration. Adipose tissue transplantation can effectively promote long-term skin expansion by contributing to vascularization and cell proliferation by means of various mechanisms. The authors' findings suggest that it would be better if the expander pocket is dissected over the superficial fascia to preserve a layer of adipose tissue with skin. In addition, their findings support the treatment of fat grafting when expanded skin presents with thinning.

LC-MS/MS quantitation of elastin crosslinker desmosines and histological analysis of skin aging characteristics in mice

Elastic fibers consist of an insoluble inner core of elastin, which confers elasticity and resilience to vertebral organs and tissues. Desmosine (DES) and isodesmosine (IDES) are potential biomarkers of pathologies that lead to decreased elastin turnover. Mice are commonly used in research to mimic humans because of their similar genetics, physiology, and organ systems. The present study thus used senescent accelerated prone (SAMP10) and senescent accelerated resistant (SAMR1) mice to examine the connection between aging and histological or biomolecular changes. Mice were divided into three groups: SAMP10 fed a control diet (CD), SAMP10 fed a high-fat diet (HFD), and SAMR1 fed a CD. The percent liver to total body weight ratio (%LW/BW), desmosines (DESs or DES/IDES) content, and histological alterations in skin samples were evaluated. DESs were quantified using an isotope-dilution liquid chromatography–tandem mass spectrometry method with isodesmosine-13C3,15N1 as the internal standard (ISTD). The assays were repeatable, reproducible, and accurate, with %CV values ≤ (1.90, 1.77, and 3.03), ISTD area %RSD of (1.54, 0.92, and 1.13), and %AC of (99.02 ± 1.86, 101.00 ± 2.30, and 101.30 ± 2.90) for the calibrations (equimolar DES/IDES, DES, and IDES, respectively). The average DESs content per dry-weight abdominal skin and %LW/BW were similar between the three groups. Histological analyses revealed elastin fibers in five randomly selected samples. The epidermis and dermal white adipose tissue layers were thicker in SAMP10 mice than SAMR1 mice. Thus, characteristic signs of aging in SAMP10 and SAMR1 mice could not be differentiated based on measurement of DESs content of the skin or %LW/BW, but aging could be differentiated based on microscopic analysis of histological changes in the skin components of SAMP10 and SAMR1 mice.

Melanopsin (OPN4) is a novel player in skin homeostasis and attenuates UVA-induced effects.

The presence of melanopsin (OPN4) has been shown in cultured murine melanocytes and was associated with ultraviolet A radiation (UVA) reception. Here we demonstrated the protective role of OPN4 in skin physiology and the increased UVA-induced damage in its absence. Histological analysis showed a thicker dermis and thinner hypodermal white adipose tissue layer in Opn4-/- (KO) mice than in wild-type (WT) animals. Proteomics analyses revealed molecular signatures associated with proteolysis, remodeling chromatin, DNA damage response (DDR), immune response, and oxidative stress coupled with antioxidant responses in the skin of Opn4 KO mice compared to WT. Skin protein variants were found in Opn4 KO mice and Opn2, Opn3, and Opn5 gene expressions were increased in the genotype. We investigated each genotype response to UVA stimulus (100kJ/m2). We found an increase of Opn4 gene expression following stimulus on the skin of WT mice suggesting melanopsin as a UVA sensor. Proteomics findings suggest that UVA decreases DDR pathways associated with ROS accumulation and lipid peroxidation in the skin of Opn4 KO mice. Relative changes in methylation (H3-K79) and acetylation sites of histone between genotypes and differentially modulated by UVA stimulus were also observed. We also identified alterations of molecular traits of the central hypothalamus-pituitary- adrenal (HPA) and the skin HPA-like axes in the absence of OPN4. Higher skin corticosterone levels were detected in UVA-stimulated Opn4 KO compared to irradiated WT mice. Taken altogether, functional proteomics associated with gene expression experiments allowed a high-throughput evaluation that suggests an important protective role of OPN4 in regulating skin physiology in the presence and absence of UVA radiation.