Stromal Vascular Fraction Research Articles

Origin of dedifferentiated adipocyte-derived cells (DFAT) during ceiling culture in an Adiponectin Cre-Recombinase mouse model.

Dedifferentiated adipose tissue-derived (DFAT) cells represent an attractive source of stem cells for tissue engineering and the potential treatment of several clinical conditions. Our objective was to determine whether DFAT cells originate from mature adipocytes and address whether contamination from the stromal vascular fraction (SVF) could be as a source for these cells. A murine adiponectin-creERT; mT/mG model was used with the excision of the cassette induced by tamoxifen injection for the cells expressing adiponectin (adipoq). This model allows distinguishing mature adipocytes (green fluorescence) from other SVF cell types (red fluorescence) based on the fluorescent protein expressed. Mature adipocytes and SVF cells were isolated from adipose tissues by collagenase digestion. Ceiling cultures were imaged by time-lapse microscopy. Confocal microscopy was used to follow cells over 21 days. Time-lapse microscopy experiments showed liposecretion occurring in mature adipocytes displaying green fluorescence. Confocal imaging allowed the identification of a heterogeneous cell population expressing green but also red fluorescence after 21 days of culture. Asymmetrical division of mature adipocytes was not observed. In conclusion, liposecretion of mature adipocytes is a phenomenon that can be observed in vitro and DFAT cells do originate from mature adipocytes. However, the population of DFAT cells is heterogenous.

Epigenetic modifications in transdifferentiation of adipose tissue-derived stromal cells into spontaneously beating cardiomyocyte-like cells

Abstract Background Adipose tissue-derived stromal vascular fraction (adipose SVF) contains pluripotent mesenchymal stem cells and rarely transdifferentiate into beating cardiomyocytes. We developed a simple culture protocol under which the adult murine inguinal adipose SVF reproductively transdifferentiates into beating cardiomyocyte-like cells (beating CM) without inductions in the primary culture. We also reported that Mef2c is a crucial factor in this conversion. However, the characteristics of beating CM and the factors that regulate the differentiation of adipose SVF toward the cardiac lineage are unknown. Purpose To investigate sequential changes in global gene expression profiles of adipose SVF in primary culture and determine the mechanism of differentiation into beating CM. Methods Adipose SVF cells were isolated from adult mice's inguinal subcutaneous fat pad and cultured using the previously established beating CM induction method (Sci Rep. 2021). At 6 time points (days 0, 3, 7, 14, 21, and 28) in primary culture, total RNA was extracted, and RNA-sequencing was performed (n = 3). The data was analyzed using Subio Platform and MetaCore software. To assess the candidate gene and proteins, adipose SVF cells were transduced with the gene using a lentivirus vector and supplemented with the specific inhibitors. The cardiac differentiation was evaluated by quantitative PCR on day 28. Results The beating CM was confirmed on days 14, 21, and 28 in the primary culture. Among prefiltered 14,574 genes, the expression level of 749 genes were significantly changed (153 genes upregulated vs. 596 genes downregulated) between days 7 and 14 (2-fold, P < 0.05), in which beating CM appeared. The GO molecular functions analysis showed that O-GluNAC transferase and histone deacetylase (HDAC)-associated genes were expressed dominantly before day 7, and KLF4-associated genes were expressed prominently after day 14 in primary culture. The expression of cardiac troponin T (Tnnt2) and myosin light chain ventricular type (Myl2) increased on day 3 and day 14, respectively. The HDAC7, an epigenetic regulator, decreased the expression on day 14 or later. Treatment with the HDAC inhibitor (150 nmol/L) increased the expression of Tnnt2 (5-fold vs. control) on day 28 in adipose SVF. Furthermore, treatment of Mef2c-transduced adipose SVFs with HDAC inhibitors increased expression of cardiac troponin T (29-fold vs. control, P < 0.05). Conclusion The time course analysis demonstrated that a remarkable change occurred in the regulation of transcription on day 14 in adipose SVF primary culture. Alterations in epigenetic modifications increased beating CM in adipose SVFs. Adipose SVF could be applied to new cardiac regeneration therapies by increasing the efficiency of introduction into the beating CM.

Comparing mechanical and enzymatic isolation procedures to isolate adipose-derived stromal vascular fraction: A systematic review.

The stromal vascular fraction of adipose tissue has gained popularity as regenerative therapy for tissue repair. Both enzymatic and mechanical intraoperative SVF isolation procedures exist. To date, the quest for the preferred isolation procedure persists, due to the absence of standardised yield measurements and a defined clinical threshold. This systematic review is an update of the systematic review published in 2018, where guidelines were proposed to improve and standardise SVF isolation procedures. An elaborate data search in MEDLINE (PubMed), EMBASE (Ovid) and the Cochrane Central Register of Controlled Trials was conducted from September 2016 to date. A total of 26 full-text articles met inclusion criteria, evaluating 33 isolation procedures (11 enzymatic and 22 mechanical). In general, enzymatic and mechanical SVF isolation procedures yield comparable outcomes concerning cell yield (2.3-18.0 × 105 resp. 0.03-26.7 × 105 cells/ml), and cell viability (70%-99% resp. 46%-97.5%), while mechanical procedures are more time consuming (8-20 min vs. 50-210 min) and cost-efficient. However, as most studies used poorly validated outcome measures on SVF characterisation, it still remains unclear which intraoperative SVF isolation method is preferred. Future studies are recommended to implement standardised guidelines to standardise methods and improve comparability between studies.

The ameliorating effects of adipose-derived stromal vascular fraction cells on blue light-induced rat retinal injury via modulation of TLR4 signaling, apoptosis, and glial cell activity.

Blue light (BL)-induced retinal injury has become a very common problem due to over exposure to blue light-emitting sources. This study aimed to investigate the possible ameliorating impact of stromal vascular fraction cells (SVFCs) on BL-induced retinal injury. Forty male albino rats were randomly allocated into four groups. The control group rats were kept in 12-h light/12-h dark. Rats of SVFC-control as the control group, but rats were intravenously injected once by SVFCs. Rats of both the BL-group and BL-SVFC group were exposed to BL for 2 weeks; then rats of the BL-SVFC group were intravenously injected once by SVFCs. Following the BL exposure, rats were kept for 8 weeks. Physical and physiological studies were performed; then retinal tissues were collected for biochemical and histological studies. The BL-group showed physical and physiological changes indicating affection of the visual function. Biochemical marker assessment showed a significant increase in MDA, TLR4 and MYD88 tissue levels with a significant decrease in TAC levels. Histological and ultrastructural assessment showed disruption of the normal histological architecture with retinal pigment epithelium, photoreceptors, and ganglion cell deterioration. A significant increase in NF-κB, caspase-3, and GFAP immunoreactivity was also detected. BL-SVFC group showed a significant improvement in physical, physiological, and biochemical parameters. Retinal tissues revealed amelioration of retinal structural and ultrastructural deterioration and a significant decrease in NF-κB and caspase-3 immunoreactivity with a significant increase in GFAP immunoreaction. This study concluded that SVFCs could ameliorate the BL-induced retinal injury through TLR-4/MYD-88/NF-κB signaling inhibition, regenerative, anti-oxidative, and anti-apoptotic effects.

Elevated Netrin-4 Expression and Its Action in Infrapatellar Fat Pad

Knee osteoarthritis (KOA) is a degenerative joint disease characterized by inflammation and cartilage degradation. The infrapatellar fat pad (IFP), located beneath the patella within the knee joint, serves as a key anatomical structure involved in cushioning and supporting the knee. It is also an active endocrine organ that secretes various bioactive substances, potentially influencing the local inflammatory environment and contributing to KOA pathogenesis. Netrin-4 (NTN4), a protein primarily known for its role in neuronal guidance, has been implicated in various non-neuronal functions, including inflammatory processes and tissue remodeling. This study aims to explore the involvement of NTN4 in KOA, focusing on its expression in the IFP and its potential impact on disease progression. This study involved 82 patients with radiographically confirmed KOA undergoing total knee arthroplasty (TKA). The correlation between NTN4 expression and OA pathology, including Kellgren–Lawrence (K/L) grades, was investigated. NTN4-expressing cells were identified in the stromal vascular fraction, including fibroblastic, hematopoietic, and endothelial cells of the IFP. To elucidate the molecular effects of NTN4, RNA sequencing (RNA-seq) was performed on fibroblastic cells treated with recombinant NTN4. Subsequent quantitative PCR (qPCR) was used to validate the RNA-seq findings. NTN4 expression was significantly elevated in the IFP of patients with advanced KOA (K/L grades 3 and 4) compared to those with early-stage disease (K/L grade 2). Higher NTN4 expression was found in fibroblastic cells, and RNA-seq analysis revealed upregulation of genes associated with pro-inflammatory pathways, including IL-17 and TNF-α signaling, and matrix degradation. Notably, genes including IL6, MMP1, CXCL1, and CXCL8 were significantly elevated, as confirmed by qPCR, indicating NTN4’s role in promoting an inflammatory and catabolic environment. Our findings suggest that NTN4 plays a significant role in the pathogenesis of KOA by promoting inflammation and matrix degradation within the IFP. Although NTN4 expression was not directly correlated with clinical symptoms, its elevated expression in fibroblastic cells and influence on inflammatory and degradative pathways suggest a potential mechanism for exacerbating joint damage. Targeting NTN4 could offer a novel therapeutic approach to mitigating inflammation and slowing disease progression in KOA, ultimately improving patient outcomes. Further research is needed to clarify NTN4’s specific roles and therapeutic potential in OA management.

Early activation of macrophage-2 with IL-4 in stromal vascular fraction increases VEGF levels and adipocyte count and maintains volume of fat graft in Wistar rats (Rattus norvegicus)

Several previous studies have demonstrated the benefits of early macrophage 2 activation fat grafts supplemented with macrophage culture. However, this approach is considered impractical in clinical settings because of intraperitoneal induction use. The aim of this study was to investigate the effect of early stromal vascular fraction (SVF) macrophage-2 activation with IL-4 on fat graft survival compared to SVF alone using an animal model for better fat graft viability. This experimental study included inguinal fat harvesting, isolated with collagenases to retrieve the SVF, and then injected with a combination of fat graft and SVF (0.3 mL) into the scalp region. The intervention group received an IL-4 intralesional injection on the third day, and the fat grafts were biopsied on days 7, 14, and 30. The primary outcomes were the final volume of the fat graft, vascular endothelial growth factor (VEGF) expression, and the adipocyte cell count using perilipin staining on immunohistochemistry examination. The group receiving IL-4 exhibited significantly higher VEGF on days 7, 14, and 30 (p=0.009, 0.009, and 0.021, respectively). Similarly, the IL-4 treatment significantly increased the perilipin concentration on days 7, 14, and 30 (p=0.008, 0.008, and 0.029, respectively). In this group, VEGF concentration was significantly increased on day 14 as compared to day 7 (p=0.009), while no significant difference was observed in the control group (p=0.090). Additionally, the IL-4 group displayed significantly less reduction of fat graft volume than the control group, as observed on days 7, 14, and 30 (p=0.009, 0.009, and 0.021, respectively). Overall, the study underscores the potential benefits of early M2 polarization in fat grafting, as well as providing practical advantages for improving fat graft volume retention.

8729 Role of PARP1 in Macrophage-dependent Regulation of Adipose Tissue Inflammation, Adipogenesis, and Diet-induced Obesity

Abstract Disclosure: J. Zhu: None. R. Gupte: None. T.S. Nandu: None. W.L. Kraus: None. D. Huang: None. Adipose tissue macrophages play a significant role in maintaining adipose tissue homeostasis, as well as promoting chronic low-grade inflammation during the development of obesity and metabolic dysfunction. However, the crosstalk between macrophages and adipocytes, especially how macrophages affect adipogenesis in obese adipose tissue, are still poorly understood. We have investigated the function of PARP1 in the control of adipogenesis by using an adipocyte precursor-specific Parp1 knockout mouse model. Here, to investigate the role of macrophage PARP1 in regulating adipogenesis, we deleted Parp1 in the myeloid lineage by crossing Parp1loxp/loxp mice with LysMCre mice (Parp1 cKOLysMCre). Macrophages-specific knockout of Parp1 dramatically reduced LPS-induced pro-inflammatory gene expression in bone marrow-derived macrophages (BMDMs). To explore whether macrophage-specific Parp1 knockout affects adipocyte differentiation, we treated the primary preadipocytes from stromal vascular fraction (SVF) of white adipose tissue with the conditioned medium from LPS-stimulated control or Parp1 cKOLysMCre BMDMs throughout a 6-day period of differentiation. We observed that exposure of preadipocytes to the conditioned medium of Parp1 cKOLysMCre macrophages promoted adipogenesis by Oil Red O staining, as well as by monitoring the expression of key proadipogenic marker genes (e.g., Adipoq and Fabp4) by RT-qPCR. To further investigate the role of macrophage-specific deletion of Parp1 in metabolic outcomes, we fed the Parp1 cKOLysMCre mice with a high fat diet for 12 weeks. The knockout mice exhibited a significant increase in body weight compared to the control mice. Interestingly, we observed a reduction of the total number of macrophages resident in the adipose tissue from macrophage-specific Parp1 knockout mice. To explore the underlying mechanism, we performed single cell RNA-seq for adipose tissue macrophages using sorted SVF cells collected from HFD-fed mice. The results demonstrated dramatic reductions in macrophage M1 marker genes and pro-inflammatory transcription factors in Parp1 cKOLysMCre mice. Taken together, our study suggests that Parp1 knockout in macrophages selectively affects the recruitment and pro-inflammatory activation of macrophages, as well as adipocyte differentiation in adipose tissue. Importantly, despite the decreased adipose tissue inflammation, macrophage-specific Parp1 knockout enhanced adipogenesis, which leads to obesity in mice.This work was supported by a grant from the NIH/NIDDK (R01 DK069710) and funds from the Cecil H. and Ida Green Center for Reproductive Biology Sciences Endowment, to W.L.K., and a grant from NSFC (82270929) to D.H. Presentation: 6/1/2024

Pilot Study: Use of Stem Cell Therapy and Diced Cartilage in Secondary Rhinoplasty Cases Clinical Outcomes: The Golden Turkish Delight.

Although many techniques in the secondary rhinoplasty field have been developed in recent years, there are debates regarding achieving results with a high satisfaction rate. We aimed to share the surgical use technique in secondary rhinoplasty patients by enriching the Turkish delight technique with mesenchymal stem cells, which we described as the golden Turkish delight (GTD) technique, and the long-term patient satisfaction results. The study was planned as prospective research, and 30 secondary rhinoplasty patients who presented to our service for rhinoplasty were included. The GTD technique was applied to these patients. The patient's satisfaction with the surgical procedure was evaluated at least 9-12 months after the surgery, and the Global Aesthetic Improvement Scale (GAIS) was used as a measurement tool. Of the participants, the satisfaction levels of 30 patients were evaluated with a 1-year follow-up on average, and the rate of those who improved was found to be 80% using the GAIS score. The rate of those with high GAIS scores and those with high satisfaction levels was approximately 56%. Twenty percent of the patients were not satisfied with the result. When we evaluate the postoperative 1-year results of our patients in terms of satisfaction and complications, we may state that the absorption that may occur in the Turkish delight technique over time could give better results with the GTD technique. In addition to GTD and fat graft support, regenerative medicine products such as stromal vascular fraction are very effective in obtaining favorable results.

In Vitro Treatment with Metformin Significantly Reduces Senescent B Cells Present in the Adipose Tissue of People with Obesity

BackgroundOur previous work has shown that senescent B cells accumulate in the human adipose tissue (AT) from people with obesity, where they express transcripts for markers associated with the senescence-associated secretory phenotype (SASP) and secrete multiple inflammatory mediators. These functions of AT-derived B cells are metabolically supported. ObjectivesTo show that Metformin (MET), a widely used hypoglycemic and antidiabetic drug, is able at least in vitro to decrease frequencies, secretory profile, and metabolic requirements of senescent B cells isolated from the AT from people with obesity. MethodsWe recruited adult females with obesity (n = 8, age 40 ± 2 y, BMI range: 33–42) undergoing breast reduction surgery, who donated their discarded subcutaneous AT. B cells from stromal vascular fractions isolated after collagenase digestion of the AT were evaluated after in vitro incubation with MET (1 mM × 106 B cells) or with a medium for the following measures. The expression of transcripts for SASP-associated markers (p16INK4a and p21CIP1/WAF1) measured by quantitative polymerase chain reaction (qPCR); secretion of inflammatory cytokines (TNF-α, IL-6, IFN-γ and IL-17A) measured by a Cytometric Bead Array); metabolic characteristics as identified by a glycolytic test and Seahorse technology, and by the expression of transcripts for glucose transporters and metabolic enzymes involved in glucose metabolic pathways, measured by qPCR. To examine differences between MET-treated compared with untreated groups, paired Student’s t tests (two-tailed) were employed. ResultsMET in vitro was able to reduce frequencies and numbers of senescent B cells, as identified by staining with β-galactosidase, as well as the secretion of inflammatory cytokines, the expression of transcripts for SASP, and metabolic markers that support intrinsic B cell inflammation. ConclusionsOur results provide evidence to support the beneficial effects of MET in reducing AT-related inflammation through its effects on senescent B cells.

Therapeutic Efficacy of Adipose Tissue-Derived Components in Neuropathic Pain: A Systematic Review.

Neuropathic pain results from a defect in the somatosensory nervous system caused by a diversity of etiologies. The effect of current treat-ment with analgesics and surgery is limited. Studies report the therapeutic use of adipose tissue-derived components to treat neuropathic pain as a new treatment modality. The aim of this systematic review was to investigate the therapeutic clinical efficacy of adipose tissue-derived components on neuro-pathic pain. PubMed, Medline, Cochrane and Embase databases were searched until August 2023. Clinical studies assessing neuropathic pain after autologous fat grafting or the therapeutic use of adipose tissue-derived com-ponents were included. The outcomes of interest were neuropathic pain and quality of life. In total, 433 studies were identified, of which 109 dupli-cates were removed, 324 abstracts were screened and 314 articles were excluded. In total, ten studies were included for comparison. Fat grafting and cellular stromal vascular fraction were used as treatments. Fat grafting indications were post-mastectomy pain syndrome, neuromas, post-herpetic neuropathy, neuro-pathic scar pain and trigeminal neuropathic pain. In seven studies, neuropathic pain levels decreased, and overall, quality of life did not improve. The therapeutic efficacy of adipose tissue-derived components in the treatment of neuropathic pain remains unclear due to the few performed clinical trials with small sample sizes for various indications. Larger and properly designed (randomized) controlled trials are required.

Efficacy of a Single Injection of Stromal Vascular Fraction in Dogs with Elbow Osteoarthritis: A Clinical Prospective Study

This study aimed to assess the efficacy of a single intra-articular injection of autologous stromal vascular fraction (SVF) in dogs with chronic lameness due to advanced elbow osteoarthritis (OA) that were unresponsive to conventional drug therapy. In this clinical, prospective, non-blinded, single-center study, twenty-three dogs received autologous SVF derived from falciform adipose tissue. Primary outcome measures over the six-month study period included clinical-orthopedic and radiographic examinations, objective gait analysis and validated owner questionnaires. In 19 of 23 joints, no progression of OA was visible radiographically. Peak vertical force improved significantly at three months and vertical impulse at six months after the injection compared to baseline. Over 33% of dogs demonstrated treatment-related improvements in lameness based on objective gait analysis. Owner questionnaires indicated significant improvement in clinical signs throughout the study period and 26% of dogs showed treatment-related improvements in pain scores according to the Canine Brief Pain Inventory. No side effects were reported. These findings suggest that autologous regenerative cell therapy may provide a promising treatment option for dogs with advanced OA that do not respond to conventional drug therapy. However, the treatment did not improve the clinical symptoms in all dogs, so it cannot be recommended for all patients.

A Novel Laboratory-Based Strategy for Single Adipocyte and Adipose-Derived Stem Cells Extraction for Transplantation: An Experimental Research.

Autologous fat grafting is widely used in plastic surgery. However, its main limitation is the low survival rate of fat grafts after transplantation. Transplantation of single adipocytes in combination with adipose-derived stem cells (ADSCs) could largely preserve the activity of the fat and improve graft survival. To verify the long-term survival rate of single adipocyte graft in vivo and its viable fat morphology for future fat grafting. Healthy adipose tissue was harvested and disassociated using fat dissociation solution, the Single-cell Suspension Preparation System (SSPS) was used to obtain a mixture of single adipocytes, ADSCs and stromal vascular fraction (SVF), and the structure of single adipocytes was verified by cell mask red and DAPI double staining. Nine male Balb/c nude mice were used, and three different graft volumes were established (0.05, 0.1 and 0.2ml). For each mouse, four sites were selected for transplantation, one for macrofat and the other three for single adipocytes, and different transplant volumes 30, 60 and 90days after transplantation. In each period, 3mice were selected to measure the volume of fat graft. Double staining with cell mask red and DAPI confirmed that the nucleus was identified intracellularly, which also indicated that the adipocytes in the single-cell suspension were structurally complete. When evaluating the transplantation, the groups with a volume of 0.05 ml and 0.2ml performed better in the single-cell fat group in all transplantation periods, the group with a volume of 0.1ml performed better in the single-cell group in the 30- and 60-day transplantation, and the differences were significant (P<0.05). In this study, the SSPS was used to obtain a new transplant material containing single adipocytes and ADSCs by enzymatic hydrolysis of adipose tissue and converted into single cells. It effectively improved the survival rate of fat grafting and the long-term effect of transplantation. 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.

Human uncultured adipose-derived stromal vascular fraction shows therapeutic potential against osteoarthritis in immunodeficient rats via direct effects of transplanted M2 macrophages

BackgroundThe uncultured adipose-derived stromal vascular fraction (SVF), consisting of adipose-derived stromal cells (ADSCs), M2 macrophages (M2Φ) and others, has shown therapeutic potential against osteoarthritis (OA), however, the mechanisms underlying its therapeutic effects remain unclear. Therefore, this study investigated the effects of the SVF on OA in a human-immunodeficient rat xenotransplantation model.MethodsOA model was induced in the knees of female immunodeficient rats by destabilization of the medial meniscus. Immediately after the surgery, human SVF (1 × 105), ADSCs (1 × 104), or phosphate buffered saline as a control group were transplanted into the knees. At 4 and 8 weeks postoperatively, OA progression and synovitis were analyzed by macroscopic and histological analyses, and the expression of collagen II, SOX9, MMP-13, ADAMTS-5, F4/80, CD86 (M1), CD163 (M2), and human nuclear antigen (hNA) were evaluated immunohistochemically. In vitro, flow cytometry was performed to collect CD163-positive cells as M2Φ from the SVF. Chondrocyte pellets (1 × 105) were co-cultured with SVF (1 × 105), M2Φ (1 × 104), and ADSCs (1 × 104) or alone as a control group, and the pellet size was compared. TGF-β, IL-10 and MMP-13 concentrations in the medium were evaluated using enzyme-linked immunosorbent assay.ResultsIn comparison with the control and ADSC groups, the SVF group showed significantly slower OA progression and less synovitis with higher expression of collagen II and SOX9, lower expression of MMP-13 and ADAMTS-5, and lower F4/80 and M1/M2 ratio in the synovium. Only the SVF group showed partial expression of hNA-, CD163-, and F4/80-positive cells in the rat synovium. In vitro, the SVF, M2Φ, ADSC and control groups, in that order, showed larger pellet sizes, higher TGF-β and IL-10, and lower MMP-13 concentrations.ConclusionsThe M2Φ in the transplanted SVF directly affected recipient tissue, enhancing the secretion of growth factors and chondrocyte-protecting cytokines, and partially improving chondrocytes and joint homeostasis. These findings indicate that the SVF is as an effective option for regenerative therapy for OA, with mechanisms different from those of ADSCs.

Combined Stromal Vascular Fraction and Fractional CO2 Laser Therapy for Hypertrophic Scar Treatment: A Systematic Review and Meta-Analysis.

Hypertrophic scars (HTSs) result from aberrant wound healing processes, leading to raised, thickened tissue with functional discomfort and cosmetic concerns. Current treatments, including corticosteroid injections and laser therapy, have limitations. Stromal vascular fraction (SVF) therapy and CO2 laser treatment offer promising avenues, with SVF therapy showing regenerative potential and CO2 laser therapy promoting precise tissue removal and wound healing. This study aims to investigate the combined application of SVF therapy and CO2 laser treatment for HTS, aiming to enhance treatment efficacy, tissue remodeling, and aesthetic outcomes, ultimately improving patient satisfaction in HTS management. PubMed, Scopus, Embase, and Web of Science databases have been searched for relevant studies. The "R" software (version 4.3.1) along with the "tidyverse" and "meta" statistical packages utilized to analyze data related to the efficiency of this combined method. A random-effects model was fitted to the data. For each study, continuous outcomes were pooled by calculating the standardized mean difference, along with their 95% confidence intervals. The assessment of heterogeneity utilized the I2 and chi-squared tests, applying the random effect model. Six articles fulfilled our inclusion criteria and were included in our review. Results from the pooled analysis of Vancouver Scar Scale (VSS) scores across three included studies indicated a significant impact of the SVF+CO2 method on VSS scores post-treatment (SMD=-3.0144; 95% CI:-4.3706 to -1.6583, p<0.0001). However, analysis of transepidermal water loss levels before and after treatment showed no significant difference (SMD=-2.7603; 95% CI: -6.8729 to 1.3522; p=0.1883). Comparatively, in a pooled analysis of two studies, the combined SVF+CO2 method demonstrated superior efficacy in VSS scores compared to other methods (SMD= -1.3573; 95% CI: -2.2475 to -0.4672, p = 0.0028), with moderate heterogeneity across studies (I^2=23.0%, p = 0.2545). The combined application of SVF and CO2 laser treatment shows significant promise in improving hypertrophic scars' appearance and texture. The SVF+CO2 method demonstrates superior efficacy compared to other modalities, suggesting its potential as a valuable therapeutic approach for hypertrophic scar management. This journal requires that authors assign a level of evidence to each article. 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 .

Adipose Tissue Plasticity: A Comprehensive Definition and Multidimensional Insight.

Adipose tissue is composed of adipocytes, stromal vascular fraction, nerves, surrounding immune cells, and the extracellular matrix. Under various physiological or pathological conditions, adipose tissue shifts cellular composition, lipid storage, and organelle dynamics to respond to the stress; this remodeling is called "adipose tissue plasticity". Adipose tissue plasticity includes changes in the size, species, number, lipid storage capacity, and differentiation function of adipocytes, as well as alterations in the distribution and cellular composition of adipose tissue. This plasticity has a major role in growth, obesity, organismal protection, and internal environmental homeostasis. Moreover, certain thresholds exist for this plasticity with significant individualized differences. Here, we comprehensively elaborate on the specific connotation of adipose tissue plasticity and the relationship between this plasticity and the development of many diseases. Meanwhile, we summarize possible strategies for treating obesity in response to adipose tissue plasticity, intending to provide new insights into the dynamic changes in adipose tissue and contribute new ideas to relevant clinical problems.

Optimizing adipose-derived stromal vascular fraction storage: Temperature and time impact on cell viability in regenerative medicine.

The adipose-derived stromal vascular fraction (SVF) plays a crucial role in regenerative medicine owing to its regenerative and immunomodulatory properties. However, the effective utilization of SVF in therapeutic applications requires careful consideration of storage conditions to maintain cell viability. We conducted a research on 43 patients of different ages and sexes who were older than 18 years. This study explored the impact of different temperatures (-80, -20, and 4 °C) on SVF storage in platelet-poor plasma for 1 and 6 months. SVF extracted using a semi-UNISTATION™ system was subjected to rigorous analysis of cell count and viability using a LUNA-STEM™ Dual Fluorescence Cell Counter. The results indicated a significant correlation between the storage conditions and SVF viability. Notably, storing SVF at 4 °C demonstrated the highest cell viability and count, while -80 °C storage exhibited the least favorable outcomes. This study emphasizes the importance of minimizing storage time to preserve SVF viability, as evidenced by a decline in both cell count and viability over a 6-month period. Comparisons with the existing literature underscore the need for precise protocols for SVF storage, with considerations for temperature and cryoprotective agents. These findings provide valuable insights for developing optimal SVF storage protocols to enhance therapeutic outcomes and reduce the need for repeated adipose tissue harvesting. Despite the limitations of the study, such as the use of a cell counter instead of flow cytometry, the results establish the foundation for further research on refining SVF storage methods. The ideal storage temperature is from 4 °C, while the length of storage time inversely affects the viability of SVF; the longer the storage time, the lower the number and the viability of SVF cells, regardless of the temperature at which they are preserved.

Mechanical force promotes tissue and molecular changes in adipose tissue regeneration post-transplantation.

Fat grafting often yields inconsistent and suboptimal results, necessitating improved fat processing techniques. A stromal vascular fraction (SVF) gel created using mechanical emulsification demonstrates superior retention rates to conventional Coleman fat grafts. This study investigated the mechanisms at play by transplanting fat aspirates from liposuction patients-either processed as Coleman fat grafts or further refined into an SVF gel via mechanical shear force-onto the backs of nude mice. The retention rate of the SVF gel after transplantation surpassed that observed for Coleman fat. Hematoxylin and eosin (HE) staining and immunofluorescence results demonstrated that the SVF gel group could form new adipose tissue characterized by well-organized mature fat structures. Mechanical shear force application induced increased mesenchymal stem cell abundance. Rather than merely surviving regeneration, fat was regenerated after transplantation, and the regenerated cells were mainly from mice, which was supported by microarray analysis. RNA-seq highlighted 601 genes expressed between SVF gel and Coleman fat groups, with 164 genes upregulated (cell cycle processes), and 437 genes downregulated (lipid metabolism). The application of mechanical shear force reduces the risk of complications and fosters cell proliferation and division, thereby enhancing the retention and regeneration of transplanted fat.

The Protective Effect of Adipose-Derived Stromal Vascular Fraction on Ovarian Function in Rats with Cyclophosphamide-Induced Ovarian Damage

Objective: The aim of this study was to investigate if adipose-derived stromal vascular fraction (SVF) treatment has any protective effect on ovarian function in rats with cyclophosphamide (CP) induced ovarian damage. Design: This was an experimental animal study. Participants/Materials, Setting, Methods: 25 mature cycling Wistar-Albino rats were randomized into four groups (n = 5 per group). Rats in groups 1 and 2 received single dose of intraperitoneal (i.p.) 1 mL/kg sodium chloride 0.9% (NaCl). Groups 3 and 4 received single dose of 75 mg/kg i.p. CP. On seventh day, SVF was prepared from adipose tissues of 5 additional rats and groups 1 and 3 received 0.9% NaCl i.p. injections while groups 2 and 4 received 0.2 mL i.p. injections of SVF. On day 21 all rats were euthanized, and serum anti-mullerian hormone (AMH) levels, primordial, primary, secondary, antral, and atretic follicle counts, AMH positive staining follicle counts along with AMH staining intensity of the follicles were evaluated. Results: Among two CP induced ovarian damaged groups, SVF treated group showed significantly higher secondary and antral follicle and lower atretic follicle counts, significantly higher mean serum AMH levels, AMH positive antral follicle count and higher intensity of AMH positive follicle scores for primary, secondary, and antral follicles when compared to untreated group. Moreover, group 1 showed no significant difference for all parameters except antral follicle count and AMH positive staining intensity scores for antral follicles when compared to group 4. Limitations: This study was conducted on experimental rat model. Conclusion: Our study demonstrated a significant protective effect of SVF against CP-induced ovarian damage which reveals the apparent need for further investigation of its precise mechanisms of action as it may provide a new treatment approach for women with premature ovarian failure.

Effect of Stromal Vascular Fraction in the Rat Model of Pharyngocutaneous Fistulas.

A pharyngocutaneous fistula is one of the complications after laryngeal and pharyngeal surgery. It may also contribute to wound healing due to adipose tissue-derived stem cells and the growth factors in the stromal vascular fraction. The aim of this study was to investigate the effects of the adipose tissue-derived stromal vascular fraction on wound healing in the pharyngocutaneous fistula model induced in rats. Approval was received from the Animal Experiments Local Ethics Committee before starting the study (29.01.2016-2016/09). Eleven male Sprague-Dawley rats weighing approximately 300 g were included in the study. The animals were randomly divided into the study and control groups so that each group would include five animals. An animal was assigned as a donor for the removal of omental adipose tissue. Among the animals in which the pharyngocutaneous fistula model was created under general anesthesia, 1 ml of the stromal vascular fraction was injected into the study group on postoperative day 1. In postoperative week 2, all the animals were sacrificed and examined histologically (epithelialization-cell infiltration - mucosal injury). IBM SPSS Statistics for Windows, version 15, was used in the analyses. A p-value <0.05 was considered significant. Epithelialization was higher in the study group compared to the control group. However, no statistically significant difference was found between the two groups (p = 0.08). The cell infiltration was found to be statistically higher in the control group compared to the study group (p = 0.03). The mucosal injury was found to be significantly higher in the control group compared to the study group (p = 0.03). According to the Pearson correlation test, a negative correlation was found between epithelialization and cell infiltration and mucosal injury (p = 0.019 and p = 0.001). A positive correlation was found between cell infiltration and mucosal injury (p = 0.009). It was shown that stromal vascular fraction had a positive effect on wound healing in the pharyngocutaneous fistula model. According to the data we have obtained, we think that it can be effective in the treatment of pharyngocutaneous fistulas after more extensive preclinical and clinical studies are carried out.

Differential Secretomes of Processed Adipose Grafts, the Stromal Vascular Fraction, and Adipose-Derived Stem Cells.

There are multiple methods to prepare lipoaspirate for autologous fat transfer; however, graft retention remains unpredictable. The purpose of this study was to compare the cellular and protein composition of adipose grafts and the stromal vascular fraction (SVF) resulting from three common techniques to prepare adipose grafts. Adipose grafts were harvested from healthy donors and processed via three techniques: centrifugation (C), a single-filter (SF) device, and a double-filtration (DF) system. Part of each graft was analyzed or further processed to isolate the SVF. Cell viability, surface markers, cytokine, and growth factors were compared between the graft and SVF as well as adipose-derived stem cells (ASCs). Overall, we found variations across the three processing techniques and among the graft components (ASCs, SVF, and fat). Cell viability within the grafts was similar (94.6%, 92.3%, and 93.6%; P = 0.93). The trend was a greater percentage of ASCs from SF versus DF or centrifugation (6.95%, 4.63%, and 1.93%, respectively, P = 0.06). Adipogenic markers (adiponectin and leptin) were similar among all three grafts (P = 0.45). Markers of tissue remodeling were greatest in the SVF compared with fat and ASCs, regardless of processing technique. There was higher relative expression of MMP-9 (2×), Extracellular matrix metalloproteinase inducer (EMMPRIN) (2.5×), endoglin (5×), and IL-8 (1.5×) in the SVF (P < 0.005). Our study identified differences in cytokine expression in adipose grafts and the SVF, particularly in cytokines important in inflammation and wound healing. These secretomes may impact graft retention and fat necrosis and have the potential implications in cell-assisted lipotransfer. There were no significant differences between the final products of any of the processing techniques.