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Background Oxidative stress induced by ischemia and hypoxia in fat transplantation is a major obstacle to graft retention. Previous studies have shown that lutein has excellent adipose tissue affinity and antioxidative stress ability, however, the effects of oral lutein on fat transplantation have not yet been studied. Objectives We aimed to investigate whether oral lutein could improve fat transplantation retention by regulating oxidative stress, apoptosis, and inflammatory cytokine levels in graft tissues. Methods Nude mice were assigned to the control group (normal saline), low-dose lutein group (10 mg/kg/day), and high-dose lutein group (20 mg/kg/day) randomly. All mice received treatment by gavage 1 week before fat grafting and continued for 2 weeks. The grafts were collected 1, 2, and 12 weeks after treatment. By conducting histological analyses, Western blotting, quantitative polymerase chain reaction and cell metabolic function detection, the regulatory effects of lutein on apoptosis and oxidative stress in grafts were demonstrated. Additionally, RNA sequencing was conducted to further clarify the efficacy of lutein on fat grafting. Results Lutein induced superior graft retention, histological structures, and more viable adipocytes than the control group. It relieved tissue oxidative stress and lipid oxidative damage by decreasing reactive oxygen species and significantly reduced inflammation and apoptosis of grafts. RNA sequencing analysis confirmed that lutein could downregulate the gene expression of oxidative stress and related inflammation and apoptosis. Conclusions Our study suggests that oral administration of lutein can improve fat graft survival by reducing the levels of oxidative stress, inflammation, and apoptosis in grafted fat. [ABSTRACT FROM AUTHOR]

Background: At present, fat transplantation is widely used in the plastic surgery industry, but the long-term preservation rate of transplanted fat decreases because of complications such as oil cysts due to the inability in macrophages to metabolize absorption. In cell-assisted lipotransfer technology, adipose-derived stem cells (ASCs) can influence the inflammatory response of grafts through the immunoregulation in macrophages, and the lipid metabolism in macrophages plays an important role in this process. Therefore, we hypothesized ASCs could improve the retention rate of fat grafts by regulating the progress of lipid metabolism in macrophages. Methods: We established fat transplantation and ASC-assisted fat transplantation model in C57BL/6 mice in vivo, and bone marrow-derived macrophages cocultured with apoptotic adipocytes were treated with or without ASCs in vitro. Graft retention, tissue structure, fibrosis, macrophage phenotype transformation, lipid deposition, mitochondrial morphology, oxygen consumption rate (OCR), fatty acid β-oxidation (FAO) level, and ATP production were assessed. Additionally, fat transplantation and ASC-assisted fat transplantation model was treated with etomoxir which inhibits mitochondrial FAO. Macrophages pretreated with etomoxir were co-cultured with apoptotic adipocytes and treated with or without ASCs. The method aboved was used for detection and verification. Results: In vivo, ASC-assisted fat transplantation improved macrophage mitochondrial expression and FAO level, promoted the early transformation of M2 macrophages, reduced the long-term lipid deposition of macrophages, and improved the retention rate of fat grafts. In vitro, ASCs up-regulated the level of mitochondrial FAO, OCR and ATP production in macrophages, reduced lipid deposition of macrophages and promoted M2 macrophages polarization by paracine function. The ability of ASCs in group pretreated with etomoxir to reduce the foaming of macrophages, promote the transformation to M2 macrophages, and improve the retention rate of fat transplantation was weakened. Conclusions: ASCs increased the retention rate of transplanted fat by upregulating mitochondrial FAO to promote M2 polaration in macrophages. In addition, ASCs up-regulate mitochondrial FAO by paracrine effect to reduce foam cells formation and promote M2 transformation in macrophages in vitro. [ABSTRACT FROM AUTHOR]

Background Persistent macrophage infiltration may lead to adverse consequences, such as calcifications and nodules in fat grafts. Lymphatic vessels, which transport inflammatory cells, are involved in regulating inflammatory responses. Less is known, however, about lymphatic vessels after fat grafting. Objectives The aim of this study was to explore the regulation of fat graft survival by lymphatic vessels. Methods A common adipose graft model was constructed to assess the processes responsible for changes in the number of lymphatic vessels in grafts. Adipose tissue samples from C57/BL6 mice and green fluorescent protein–expressing mice were cross-grafted to determine the source of lymphatic vessels. The number of lymphatic vessels in the grafts was increased by treatment with vascular endothelial growth factor C, and the effects of this increase on fat grafting were evaluated. Results The number of lymphatic vessels was greater in postgrafted fat than in inguinal fat before transplantation, with lymphatic vessels in these grafts gradually transitioning from donor to recipient sources. Lymphatic vessels grew more slowly than blood vessels during early stages of grafting; during later stages, however, the number of blood vessels declined markedly, with more lymphatic vessels than blood vessels being observed 60 days after grafting. Vascular endothelial growth factor C treatment increased graft lymphatics and distant volume retention, while reducing fibrosis and oil sacs. Lymphatic vessels acted as drainage channels for macrophages, with the degree of sustained macrophage infiltration decreasing with increases in the number of lymphatic vessels. Conclusions Increasing the number of lymphatic vessels is beneficial for fat graft survival, which may be related to a reduction in prolonged macrophage infiltration. Level of Evidence: 4 [ABSTRACT FROM AUTHOR]

Abstract Background At present, fat transplantation is widely used in the plastic surgery industry, but the long-term preservation rate of transplanted fat decreases because of complications such as oil cysts due to the inability in macrophages to metabolize absorption. In cell-assisted lipotransfer technology, adipose-derived stem cells (ASCs) can influence the inflammatory response of grafts through the immunoregulation in macrophages, and the lipid metabolism in macrophages plays an important role in this process. Therefore, we hypothesized ASCs could improve the retention rate of fat grafts by regulating the progress of lipid metabolism in macrophages. Methods We established fat transplantation and ASC-assisted fat transplantation model in C57BL/6 mice in vivo, and bone marrow-derived macrophages cocultured with apoptotic adipocytes were treated with or without ASCs in vitro. Graft retention, tissue structure, fibrosis, macrophage phenotype transformation, lipid deposition, mitochondrial morphology, oxygen consumption rate (OCR), fatty acid β-oxidation (FAO) level, and ATP production were assessed. Additionally, fat transplantation and ASC-assisted fat transplantation model was treated with etomoxir which inhibits mitochondrial FAO. Macrophages pretreated with etomoxir were co-cultured with apoptotic adipocytes and treated with or without ASCs. The method aboved was used for detection and verification. Results In vivo, ASC-assisted fat transplantation improved macrophage mitochondrial expression and FAO level, promoted the early transformation of M2 macrophages, reduced the long-term lipid deposition of macrophages, and improved the retention rate of fat grafts. In vitro, ASCs up-regulated the level of mitochondrial FAO, OCR and ATP production in macrophages, reduced lipid deposition of macrophages and promoted M2 macrophages polarization by paracine function. The ability of ASCs in group pretreated with etomoxir to reduce the foaming of macrophages, promote the transformation to M2 macrophages, and improve the retention rate of fat transplantation was weakened. Conclusions ASCs increased the retention rate of transplanted fat by upregulating mitochondrial FAO to promote M2 polaration in macrophages. In addition, ASCs up-regulate mitochondrial FAO by paracrine effect to reduce foam cells formation and promote M2 transformation in macrophages in vitro.

Background: Facial aging involves ptosis, adipose atrophy, and skeletal resorption. Depletion of adipose tissue primarily affects the deep facial fat compartment, leading to facial depression or ptosis, accompanied by atrophy of the superficial compartment. Restoring volume in the deep fat compartment is crucial for facial rejuvenation, while enhancing its supportive properties is also important. The superficial fat compartment contains small-sized adipocytes, and autologous fat grafting is a popular approach. However, variability in fat retention, homogeneity, and processing methods can impact outcomes, necessitating careful selection of a suitable fat processing material for precise facial fat grafting. Method: A retrospective study was conducted on 50 patients who underwent facial augmentation using combined transplantation of high-density fat (HDF) and condensed low-density fat (CLDF) and 25 patients who underwent conventional Coleman fat grafting. Coleman fat was harvested by standard technique and the adipose tissue was divided into HDF and CLDF fractions through centrifugation. Subsequently, the low-density fat fraction was subjected to a process involving physical disruption followed by additional centrifugation to obtain CLDF. The CLDF fraction was consequently injected into the pre-SMAS subcutaneous layer of the superficial fat compartments. Patient satisfaction was evaluated using a typical Likert scale. Photographs were taken and imageological examinations were performed before and after treatment. Result: The CLDF+HDF grafting group demonstrated a significantly shorter duration of swelling (6.0 ± 1.2 to 12.6 ± 3.3 days) and higher level of patient satisfaction when compared to the Coleman fat group. No serious complications were observed among all the patients who received the injections. Conclusion: The use of this new treatment approach allows for precise fat transplantation in facial regions. The use of high-concentration fat filling for deep facial layers and CLDF filling for superficial layers is a safe and effective treatment plan for facial rejuvenation. Level of Evidence IV: 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. [ABSTRACT FROM AUTHOR]

Autologous fat transplantation is limited by the uncertainty of graft retention, impeding its application. Among the current strategies for processing lipoaspirates, high-density fat (HDF) is recommended owing to the enrichment of stem cells and washing before cotton concentration for simplicity of operation. Poloxamer 188 (P188) washing has been shown to repair the membranes of damaged cells. This study aimed to investigate the effect of P188-washing on fat graft survival and identify the best technique for processing lipoaspirates. Lipoaspirates were prepared using centrifugation to obtain HDF, which was then washed with saline or P188 followed by cotton concentration. Tissue integrity, adipocytic activity, and viability of stromal vascular fraction (SVF) in the samples from the 3 groups were assessed. Samples were sequenced in vitro using high-throughput RNA-seq, and differentially expressed genes were validated using qPCR and western blotting (WB). After transplantation under the dorsum of nude mice for 8 weeks, the grafts were extracted and examined for residual volume, histologic characteristics, and vascularization. The HDF and P188 groups showed a higher survival rate of SVF, more Ki67-positive cells, intact tissue structure, and lesser fibrosis than the saline group. There were no significant differences in the density of SVF and residual volume of grafts. HDF showed significantly improved vascularization during 8 weeks. Through RNA-seq and bioinformatic analysis, notable changes in several related genes after transplantation were observed. P188 treatment can prevent cells from apoptosis and preserve tissue viability, thereby improving graft quality. HDF contains large amounts of SVF and can be regarded as an excellent grafting material. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Several studies show how submuscular breast reconstruction is linked to animation deformity, shoulder dysfunction, and increased postoperative chest pain, when compared to prepectoral breast reconstruction. In solving all these life-impairing side effects, prepectoral implant pocket conversion has shown encouraging results. Objectives The aim of this study was to propose a refinement of the prepectoral implant pocket conversion applied to previously irradiated patients. Methods We conducted a retrospective study on 42 patients who underwent previous nipple- or skin-sparing mastectomy and immediate submuscular reconstruction, followed by radiotherapy. We performed fat grafting sessions as regenerative pretreatment. Six months after the last fat graft, we performed the conversion, with prepectoral placement of micropolyurethane foam–coated implants. We investigated the preconversion and postconversion differences in upper limb range of motion, Upper Extremity Functional Index, and patient satisfaction with the breast and physical well-being of the chest. Results We reported a resolution of animation deformity in 100% of cases. The range of motion and the Upper Extremity Functional Index scores were statistically improved after prepectoral implant pocket conversion. BREAST-Q scores for satisfaction with the breast and physical well-being of the chest were also improved. Conclusions The refined prepectoral implant pocket conversion is a reliable technique for solving animation deformity and improving quality of life in patients previously treated with submuscular reconstruction and radiotherapy. Level of Evidence: 3 [ABSTRACT FROM AUTHOR]

Background Gluteal augmentation with autologous fat transfer is one of the fastest growing aesthetic surgical procedures worldwide over the past decade. However, this procedure can be associated with high mortality from fatal pulmonary fat embolism events caused by intramuscular injection of fat. Ultrasound-guided fat grafting allows visualization of the transfer in the subcutaneous space, avoiding intramuscular injection. Objectives The aim of this study was to assess the safety and efficacy of gluteal fat grafting performed with ultrasound-guided cannulation. Methods A retrospective chart review of all patients undergoing ultrasound-guided gluteal fat grafting at the authors' center between 2019 and 2022 was performed. All cases were performed by board-certified and board-eligible plastic surgeons under general anesthesia in ASA Class I or II patients. Fat was only transferred to the subcutaneous plane when over the gluteal muscle. Patients underwent postoperative follow-up from a minimum of 3 months up to 2 years. Results were analyzed with standard statistical tests. Results The study encompassed 1815 female patients with a median age of 34 years. Controlled medical comorbidities were present in 14%, with the most frequent being hypothyroidism (0.7%), polycystic ovarian syndrome (0.7%), anxiety (0.6%), and asthma (0.6%). Postoperative complications occurred in 4% of the total cohort, with the most common being seroma (1.2%), local skin ischemia (1.2%), and surgical site infection (0.8%). There were no macroscopic fat emboli complications or mortalities. Conclusions These data suggest that direct visualization of anatomic plane injection through ultrasound guidance is associated with a low rate of complications. Ultrasound guidance is an efficacious adjunct to gluteal fat grafting and is associated with an improved safety profile that should be considered by every surgeon performing this procedure. Level of Evidence: 3 [ABSTRACT FROM AUTHOR]

Background Traditional facelift surgery does not behave well in the correction of nasolabial folds, which is a common clinical problem and needed to be improved. Objectives To investigate the effect of free dermal fat grafting during facelift surgery for the treatment of nasolabial folds. Methods This prospective cohort study involved 80 patients with moderate to severe nasolabial folds and facial skin dermatolysis. Fifty of them underwent facelift surgery combined with free dermal fat grafting, and 30 of them underwent traditional facelift surgery. These patients were followed up 2 months, 6 months, and 1 year after the surgery to evaluate the effect. Results The difference in Wrinkle Severity Rating Scale (WSRS) scores, assessed at each follow-up, between the patients who underwent and did not undergo free dermal fat grafting during facelift surgery, was statistically significant. For patients who underwent free dermal fat grafting during facelift surgery, the WSRS scores assessed at 2 months, 6 months, and 1 year after the surgery were significantly different from those before the surgery. The analytic results of FACE-Q indicated a high level of overall satisfaction rate. No major complications were recorded. Conclusions Free dermal fat as a filler for nasolabial folds can achieve excellent therapeutic effect. The combination of facelift surgery with free dermal fat grafting for the treatment of nasolabial folds can provide very good long-term results and a high patient satisfaction rate for patients with symptoms of facial aging such as facial dermatolysis, obvious wrinkles, and deep nasolabial folds. Level of Evidence: 4 [ABSTRACT FROM AUTHOR]

Background Enhancing graft fat survival remains a paramount challenge in autologous fat transplantation surgeries. Dedifferentiated fat cells (DFATs) and adipose-derived stem cells (ASCs) represent 2 pivotal cells with potential to improve fat graft survival rates. Objectives In this study we aimed to compare the effectiveness of DFATs and ASCs in promoting fat graft survival, emphasizing their adipogenic and angiogenic capabilities. Methods Both in vitro and in vivo experiments were conducted. In vitro assessments compared adipogenesis, angiogenesis, osteogenesis, chondrogenesis, cell migration abilities, and surface markers. For in vivo evaluation, a cell-assisted lipotransfer animal model was employed to gauge graft volume retention and histological morphology. Analysis techniques included hematoxylin and eosin staining, Western blotting, and real-time polymerase chain reaction. Results In vitro findings suggested a slight superiority of DFATs in adipogenesis and angiogenesis compared to ASCs. In vivo tests demonstrated both cell types surpassed the control in terms of graft volume retention, with the DFATs group marginally outperforming in retention rates and the ASC group presenting a slightly enhanced graft tissue structure. Conclusions Our study underscores the distinct advantages of DFATs and ASCs in bolstering fat graft survival, offering potentially novel insights for plastic surgeons aiming to elevate fat graft survival rates. [ABSTRACT FROM AUTHOR]

Background Weight loss leads to excessive flaccidity, volume loss, and tissue descent in the gluteal region. Translated autologous flaps during lower body lifting have been utilized in patients; they address sagging tissue and the lack of volume. However, sometimes use of these autologous flaps does not provide adequate gluteal projection, and a second procedure with fat injection may be required. Objectives The authors describe their technique of a lower body lift with a lumbosacral flap in association with liposuction and lipofilling for gluteoplasty. Methods A prospective series of 23 post–bariatric surgery individuals who underwent a lower body lift with lumbosacral flap gluteal augmentation, liposuction, and lipofilling between January 2021 and September 2022 were described. The satisfaction rate and complications were assessed 6 months postoperatively with a validated questionnaire (BODY-Q scale). Results The patients had a mean age of 38.18 (range, 28-56 years) and median body mass index of 26. Four patients with dehiscence were diagnosed and treated conservatively. All wound breakdowns were observed in the paramedian plane of the torsoplasty. No reoperations were performed. The mean satisfaction percentage of the BODY-Q scale transformed score was 97.5. Conclusions A technique for a lower body lift with buttock augmentation combined with liposuction and fat grafting was presented. In future studies other techniques to maximize gluteal contouring should be investigated. [ABSTRACT FROM AUTHOR]

Introduction: Progressive hemifacial atrophy (PHA) is a nonnegligible disease, and its treatment currently lacks consensus. We aim to conduct an analysis of PHA patients to summarize the postoperative effect. Moreover, we introduced the free serratus anterior muscle-fascial composite tissue flap as a safe and novelty surgical procedure for moderate-severe PHA. Methods: This clinical study included four patients who received a free serratus anterior muscle-fascial composite tissue flap and 19 patients who received Coleman fat transplantation. Preoperative (preoperative photograph and imageological examination) and postoperative (postoperative photograph, complications, therapeutic effect, and satisfaction) assessments were performed for all PHA patients. Body Image Concern Inventory (BICI), Self-rating Anxiety Scale (SAS), Self-rating Depression Scale (SDS) were performed preoperatively and postoperatively. Results: All the cases were cured with a good appearance with two kinds of operations. Free serratus anterior muscle-fascial composite tissue flap could correct face defects in one surgery and achieve good long time and short-time postoperative satisfaction in moderate-severe PHA. Fat transplantation could also enhance appearance in numerous operations for mild-moderate PHA. The volume of free-fat grafts decreased obviously after implantation in many cases. So, many patients (42.11%) accepted a series of operations to achieve satisfied postoperative effect. BICI, SAS, SDS score decreased a year later in all patients. Conclusion: Free serratus anterior muscle-fascial composite tissue flap transplantation is an effective and safe treatment for moderate to severe PHA.

Summary: The induction of thermogenesis in brown adipose tissue is emerging as an attractive therapy for obesity and metabolic syndrome. However, the long‐term efficacy and safety of clinical pharmaceutical agents have yet to be fully characterized. The transplantation of brown adipose tissue represents an alternative approach that might have a therapeutic effect by inducing a long‐term increase in energy expenditure. However, limited tissue resources hinder the development of transplantation. Stem cell‐based therapy and brown adipose tissue engineering, in addition to transplantation, represent alternative approaches that might resolve this problem. In this article, we discuss recent advances in understanding the mechanisms and applications of brown adipose tissue transplantation in the treatment of obesity and related metabolic disorders. Specifically, the induction of brown adipocytes and the fabrication of engineered brown adipose tissue as novel transplantation resources have long‐term effects on ameliorating metabolic defects in rodent models. Additionally, we explore future prospects regarding the development of three‐dimensional engineered brown adipose tissue and the associated challenges. [ABSTRACT FROM AUTHOR]

Background The safety of gluteal fat grafting is a global concern in plastic surgery. Objective The goal of this study was to test whether fat grafting to the buttocks with Auto Stop Reach (ASR) technology prevents penetration from the subcutaneous space into the fascia and muscle layers of the buttocks. Methods Fat transfer simulation was performed with blue dye on 8 fresh tissue cadaver buttocks by 3 board-certified plastic surgeons (S.S.K., S.C., B.W.). An open control was utilized to visualize the process in the different anatomic layers, and all of the other procedures were performed blindly, akin to live surgery. After blue dye transfer reached maximum capacity (ranging from 400-800 mL per buttock), dissection of the anatomical layers of the buttocks was performed to determine the plane(s) of injection. Results Blue dye fat transfer injection to the buttocks did not penetrate the gluteal fascia or muscle layers from the subcutaneous space while using ASR. Conclusions Auto Stop Reach technology supports the safety of gluteal fat transfer in the subcutaneous space by board-certified plastic surgeons. Level of Evidence: 4 [ABSTRACT FROM AUTHOR]

Progressive hemifacial atrophy (PHA) is a nonnegligible disease, and its treatment currently lacks consensus. We aim to conduct an analysis of PHA patients to summarize the postoperative effect. Moreover, we introduced the free serratus anterior muscle-fascial composite tissue flap as a safe and novelty surgical procedure for moderate-severe PHA. This clinical study included four patients who received a free serratus anterior muscle-fascial composite tissue flap and 19 patients who received Coleman fat transplantation. Preoperative (preoperative photograph and imageological examination) and postoperative (postoperative photograph, complications, therapeutic effect, and satisfaction) assessments were performed for all PHA patients. Body Image Concern Inventory (BICI), Self-rating Anxiety Scale (SAS), Self-rating Depression Scale (SDS) were performed preoperatively and postoperatively. All the cases were cured with a good appearance with two kinds of operations. Free serratus anterior muscle-fascial composite tissue flap could correct face defects in one surgery and achieve good long time and short-time postoperative satisfaction in moderate-severe PHA. Fat transplantation could also enhance appearance in numerous operations for mild-moderate PHA. The volume of free-fat grafts decreased obviously after implantation in many cases. So, many patients (42.11%) accepted a series of operations to achieve satisfied postoperative effect. BICI, SAS, SDS score decreased a year later in all patients. Free serratus anterior muscle-fascial composite tissue flap transplantation is an effective and safe treatment for moderate to severe PHA. [ABSTRACT FROM AUTHOR]

Background The volume and position of the buccal fat pad (BFP) change with age, which manifests as a hollow midface. Previous studies showed that autologous fat grafting for BFP augmentation could effectively ameliorate midfacial hollowing. Objectives The aim of this study was to introduce a modified fat grafting technique for female patients with midfacial hollowing to restore the volume of BFP, and to evaluate the safety and effectiveness of this approach. Methods Two cadavers were used for the dissection of the BFP and to demonstrate the surgical procedures. Forty-eight patients were treated for midfacial hollowing with the modified grafting strategy. The BFP was filled through a percutaneous zygomatic incision and an immediate amelioration in the hollow area was observed. Improvements were evaluated from measurements of the ogee line and ogee angle, FACE-Q questionnaires, and 3-party satisfaction ratings. Clinical profiles were reviewed and statistically analysed. Results The mean [standard deviation] ogee angle was 6.6° [1.9°] preoperatively and 3.9° [1.4°] postoperatively (average reduction, 2.7°). Patients' ogee lines were smoother postoperatively, with marked improvements in overall appearance, psychological well-being, and social confidence. Patients reported high satisfaction with decision-making and postoperative outcomes and felt 6.61 [2.21] years younger. Overall, 88%, 76%, and 83% of the cases were graded as good or excellent in improvement by surgeon, patient, and the third party, respectively. Conclusions For age-dependent midfacial hollowing in female patients, the modified percutaneous grafting technique described here was safe and efficacious in restoring BFP volume. This technique produced a smoother ogee line and a natural, younger midfacial contour. Level of Evidence: 4 [ABSTRACT FROM AUTHOR]

Background Traditional plication techniques have been ineffective in addressing the anterior midface when compared to the sub–superficial musculoaponeurotic system (SMAS) "deep plane" approaches. However, by moving the plication much closer to the mobile medial fat tissues, a more effective and long-lasting plication can be accomplished without releasing the SMAS layer. Objectives The authors' "Delta facelift" approach combines a rotation vertical advancement of the midface fat with a dual-vector platysmaplasty and deep cervicoplasty as indicated for a harmoniously youthful neck. Methods A retrospective chart review was performed on all patients who underwent facial rejuvenation with the Delta facelift technique between January 1, 2012, and May 30, 2021, for patient demographics, procedure details, outcomes, and complications. Results A total of 283 patients underwent Delta facelift (273 females, 10 males). The average age was 60.8 years old. Primary facelift was performed in 229 patients, whereas 54 facelifts were secondary or further procedures. Adjunctive procedures included autologous fat grafting (93%), blepharoplasty (52%), and skin rejuvenating procedures (35%). There were 11 self-resolving neuropraxias, 6 minor hematomas, and 6 infections. Nine patients underwent repeat Delta facelift at an average of 9.3 years. Conclusions The Delta rotation vertical advancement of the anterior facial fat counters the descent and deflation associated with facial aging. Dual-vector platysmaplasty, with or without myotomy, effectively manages the jowl and delineates the jawline. Addition of deep cervicoplasty is recommended for patients with oblique necks or those with subplatysmal volume excess. Level of Evidence: 3 [ABSTRACT FROM AUTHOR]

Background Fat grafting is an effective procedure for breast augmentation, but the variations in this technique result in unpredictable fat retention. Therefore, animal models are needed to simulate the operation and the optimal layer for fat retention. Objectives An autologous fat grafting murine model for breast augmentation was built to detect a new layer for fat grafting in the chest. Methods The left side of the female rat inguinal fat flap was harvested, dissected into small pieces, and autotransplanted into 3 different layers of the breast. Retention rate and hematoxylin and eosin (H&E) staining were measured at 1, 4, 8 12, and 16 weeks. Immunofluorescence staining was utilized to detect adipocytes and endothelial cells, and immunohistochemistry was conducted to evaluate the expression of integrins β1 and α6. Results The volume of fat grafts slightly grew in the intramuscular and submuscular layers at Week 4. Retention rates in the subcutaneous layer and submuscular layer were significantly higher than the intramuscular layer at Week 16. H&E staining showed that oil cysts existed in the subcutaneous layer throughout the 16 weeks. At the terminal time point, well-vascularized mature adipose structures were observed in intramuscular and submuscular layers, with smaller adipocytes in intramuscular layers. Immunohistochemistry analysis showed that integrin β1 was identically expressed in every adipocyte in all the layers, whereas integrin α6 selectively expressed in bigger adipocytes in the intramuscular layer. The expression intensities of integrin β1 and α6 were significantly higher in the intramuscular layer than in the subcutaneous and submuscular layers. Conclusions The angiogenic and moderate mechanical environment makes the submuscular layer the optimal layer for fat retention. [ABSTRACT FROM AUTHOR]

In cell-assisted lipotransfer, adipose-derived stem cells play a crucial role in enhancing fat graft retention. In vitro, human adipose-derived stem cells were modified with Bcl-2 gene. In vivo, aspirated fat was mixed with the Bcl-2-modified adipose-derived stem cells and then transplanted subcutaneously into nude mice. The retention of fat graft was evaluated. The surviving Bcl-2-modified adipose-derived stem cells were tracked after transplantation. Capillary density was quantified after transplantation. Transplantation with Bcl-2-modified adipose-derived stem cells enhanced fat graft retention by 49% and 114% at 6 weeks compared with the Fat + vector-modified adipose-derived stem cell group and Fat-only group, respectively. Transplants from the Fat + Bcl-2-modified adipose-derived stem cell group had significantly more intact adipocytes and lower levels of fat necrosis and fibrosis at 6 weeks. The survival of Bcl-2-modified adipose-derived stem cells increased by 33% at 3 weeks and 54% at 6 weeks, respectively, compared with vector-modified adipose-derived stem cells. The capillary density was 24% higher in Fat + Bcl-2-modified adipose-derived stem cell group than in Fat + vector-modified adipose-derived stem cell group or 60% higher than in Fat-only group at 3 weeks.

Objective To compared the effects of washing and filtering treatment modes with different apertures on the survival rate and vascularization of transplanted plants after particle fat transplantation. Methods From October 2018 to April 2019, granular adipose tissue was obtained by manual liposuction. The adipose tissue was treated by the static method (group A), the centrifugal method (group B), and the filtration with different apertures (group C) in the fat treatment device with a closed environment. Each group of granular fat was transplanted to the back of the nude mice, and the grafts were extracted after 1 week, 2 weeks, 4 weeks and 8 weeks. The differences in vascularization and survival rate of the grafts were observed by HE staining, Masson staining, PerilipinA immunofluorescence staining and CD31 immunofluorescence staining. Results In vitro, the volume of adipocytes observed by the static method was the largest, followed by 2.4 mm. In animal experiments, the filtration method had the best retention rate of transplanted fat, and the 1.2 mm group had the highest retention rate. Under the 1.2 mm filtration condition, the size of fat particles can be effectively controlled, fibrous tissues and cell impurities can be removed. At the same time, the concentration and vascularization of Adipose-derived stem cells can be increased, and the fat retention rate can be improved. Conclusion The adipose tissue treated by 1.2 mm pore size filtration has a good fat retention rate and is rich in adipose stem cells, which can be popularized in clinical practice. [ABSTRACT FROM AUTHOR]

In cell-assisted lipotransfer, adipose-derived stem cells play a crucial role in enhancing fat graft retention. In vitro, human adipose-derived stem cells were modified with Bcl-2 gene. In vivo, aspirated fat was mixed with the Bcl-2-modified adipose-derived stem cells and then transplanted subcutaneously into nude mice. The retention of fat graft was evaluated. The surviving Bcl-2-modified adipose-derived stem cells were tracked after transplantation. Capillary density was quantified after transplantation. Transplantation with Bcl-2-modified adipose-derived stem cells enhanced fat graft retention by 49% and 114% at 6 weeks compared with the Fat + vector-modified adipose-derived stem cell group and Fat-only group, respectively. Transplants from the Fat + Bcl-2-modified adipose-derived stem cell group had significantly more intact adipocytes and lower levels of fat necrosis and fibrosis at 6 weeks. The survival of Bcl-2-modified adipose-derived stem cells increased by 33% at 3 weeks and 54% at 6 weeks, respectively, compared with vector-modified adipose-derived stem cells. The capillary density was 24% higher in Fat + Bcl-2-modified adipose-derived stem cell group than in Fat + vector-modified adipose-derived stem cell group or 60% higher than in Fat-only group at 3 weeks. [ABSTRACT FROM AUTHOR]

Adipose tissue engraftment has become a promising strategy in the field of regenerative surgery; however, there are notable challenges associated with it, such as resorption of 50‑90% of the transplanted fat or cyst formation due to fat necrosis after fat transplantation. Therefore, identifying novel materials or methods to improve the engraftment efficiency is crucial. The present study investigated the effects of nervonic acid (NA), a monounsaturated very long‑chain fatty acid, on adipogenesis and fat transplantation, as well as its underlying mechanisms. To assess this, NA was used to treat cells during adipogenesis in vitro , and the expression levels of markers, including PPARγ and CEBPα, and signaling molecules were detected through reverse transcription‑quantitative PCR and western blotting. In addition, NA was mixed with fat grafts in in vivo fat transplantation, followed by analysis through Oil Red O staining, hematoxylin & eosin staining and immunohistochemistry. It was demonstrated that NA treatment accelerated adipogenesis through activation of the Akt/mTOR pathway and inhibition of Wnt signaling. NA treatment enriched the expression of Akt/mTOR signaling‑related genes, and increased the expression of genes involved in angiogenesis and fat differentiation in human mesenchymal stem cells (MSCs). Additionally, NA effectively improved the outcome of adipose tissue engraftment in mice. Treatment of grafts with NA at transplantation reduced the resorption of transplanted fat and increased the proportion of perilipin‑1 + adipocytes with a lower portion of vacuoles in mice. Moreover, the NA‑treated group exhibited a reduced pro‑inflammatory response and had more CD31 + vessel structures, which were relatively evenly distributed among viable adipocytes, facilitating successful engraftment. In conclusion, the present study demonstrated that NA may not only stimulate adipogenesis by regulating signaling pathways in human MSCs, but could improve the outcome of fat transplantation by reducing inflammation and stimulating angiogenesis. It was thus hypothesized that NA could serve as an adjuvant strategy to enhance fat engraftment in regenerative surgery.

BACKGROUND: Autologous fat is an ideal filler that repairs soft tissue defects, but the long-term survival rate of adipose tissue after transplantation has uncertainty. We explored the effect of adipose tissue structure on the survival of fat transplantation, providing theoretical basis for improving the clinical effect of fat transplantation. OBJECTIVE: To investigate the viability of different fat derivatives in vitro and the outcome after transplantation. METHODS: The adipose tissue obtained after liposuction was prepared into four kinds of adipose derivatives: large granular adipose tissue, medium granular adipose tissue, small granular adipose tissue and stromal vascular fraction gel. Fat acquisition rate and histological structural integrity, content, activity and migration ability of adipose-derived stem cells were compared. Four groups of adipose derivatives were randomly injected into the back of nude mice. The survival rate of the grafts, tissue structure observation and CD31 immunohistochemical staining were performed 1 and 12 weeks after transplantation. RESULTS AND CONCLUSION: (1) The volume acquisition rates of large, medium, small granular fat and stromal vascular fraction gel were (71.43±2.87)%, (57.14±3.11)%, (45.72±3.97)%, and (11.30±2.33)%, respectively. The fat histological structure of the large particles was the most complete, followed by the medium and small granular fat groups, and the tissue structure of stromal vascular fraction gel was basically completely destroyed. (2) The contents of adipose stem cells obtained from large, medium, small granular fat and stromal vascular fraction gel were (5.03±0.56)×107 L-1, (3.77±0.46)×107 L-1, (2.01±0.64)×107 L-1, and (14.84±1.09)×107 L-1, respectively, with significant differences (P < 0.05). (3) The proliferation ability of adipose stem cells in large granular fat group was the best, followed by medium and small granular fat groups; the proliferation ability of stromal vascular fraction gel group was the worst. (4) The migration ability of adipose stem cells in large granular fat group was the best, followed by medium granular fat group, while that in the small granular fat group and stromal vascular fraction gel group was poor. (5) After transplantation, the volume retention rate of stromal vascular fraction gel group was the highest, followed by large granular fat group, while small granular fat group was the worst. (6) After 12 weeks of fat transplantation, fat cells in large granular fat group were partially destroyed; cells in medium granular fat group and small granular fat group were largely destroyed and some vesicles were formed; a large number of mature fat cells were formed in stromal vascular fraction gel group. (7) At 12 weeks after transplantation, the formation of blood vessels in large granular fat group and stromal vascular fraction gel group was more than that in medium granular fat group, while small granular fat group was the least, with significant differences (P < 0.05). There was no significant difference between the large granular fat group and stromal vascular fraction gel group (P > 0.05). (8) Results show that structural integrity of adipose tissue affects adipose stem cell production, vitality and adipose tissue survival rate after transplantation. Suitable options are made according to the characteristics of different fat derivatives to achieve the best filling effect. [ABSTRACT FROM AUTHOR]

Subcutaneous adipose tissue (SAT) is recognized as a highly active metabolic and inflammatory tissue. Interestingly, adipose tissue transplantation is widely performed in plastic surgery via lipofilling, yet little is known about the gene alteration of adipocytes after transplantation. We performed an RNA-expression analysis of fat transplants before and after fat transplantation. In C57BL/6 N mice SAT was autologously transplanted. Samples of SAT were analysed before transplantation, 7, and 15 days after transplantation and gene expression profiles were measured. Analysis revealed that lipid metabolism-related genes were downregulated while inflammatory and extracellular matrix related genes were up-regulated 7 and 15 days after transplantation. When comparing gene expression profile 7 days after transplantation to 15 days after transplantation developmental pathways showed most changes.

Autologous fat transplantation is a widely used procedure for surgical reconstruction of tissues. The resorption rate of this transplantation remains high and unpredictable, reinforcing the need of adjuvant treatments that increase the long‐term stability of grafts. Adipose‐derived stem cells (ASC) introduced as single cells in fat has been shown clinically to reduce the resorption of fat grafts. On the other hand, the formulation of ASC into cell spheroids results in the enhancement of their regenerative potential. In this study, we developed a novel method to produce highly homogeneous ASC spheroids and characterized their features and efficacy on fat transplantation. Spheroids conserved ASC markers and multipotency. A regenerative gene expression profile was maintained, and genes linked to autophagy were upregulated whereas proliferation was decreased. Their secreted proteome was enriched in comparison with single‐cell ASC suspension. Addition of spheroids to fat graft in an animal model of transplantation resulted in a better graft long‐term stability when compared to single ASC suspension. In conclusion, we provide a novel method to manufacture homogenous ASC spheroids. These ASC spheroids are superior to ASC in single‐cell suspension to improve the stability of fat transplants, reinforcing their potential in reconstructive surgery. [ABSTRACT FROM AUTHOR]

Objective To explore the clinical efficacy of facial liposuction combined with autologous fat transplantation in facial contour remodeling. Methods From January 2018 to January 2020, 138 patients with poor facial contour underwent facial liposuction combined with autologous fat transplantation to improve their facial morphology. Results All patients were followed up for more than 12 months. Among these patients, 134 cases were filled once and 4 cases were filled twice. The facial contour was significantly improved. The patient satisfaction was 94.2% (130/138). Conclusion Facial liposuction combined with autologous fat transplantation for facial contour reconstruction has the characteristics of minimally invasive, safe and effective. The facial contour can be improved. Patients are satisfied with the postoperative contour reconstruction. It should be considerable for clinical promotion and application. [ABSTRACT FROM AUTHOR]

Brown adipose tissue (BAT) transplantation is a promising means of increasing whole‐body energy metabolism to ameliorate obesity. However, the changes in BAT following transplantation and the effects of the microenvironment of the recipient site on graft function have yet to be fully characterized. Therefore, we aimed to determine the effects of transplanting BAT from C57BL/6 mice into the dorsal subcutaneous region or deep to the quadriceps femoris muscle of leptin‐deficient ob/ob mice. Subcutaneously transplanted BAT lost features of BAT and demonstrated greater inflammatory cell infiltration and more oil cysts 16 weeks following transplantation. By contrast, the sub‐muscularly transplanted BAT maintained features of BAT and was more highly vascularized. Interestingly, sub‐muscular BAT transplantation led to a significant increase in oxygen consumption and less inflammation in subcutaneous fat, which was associated with long‐term reductions in insulin resistance and body mass gain, whereas the subcutaneous transplants failed after 16 weeks. These results demonstrate that the beneficial effects of BAT transplantation depend upon the microenvironment of the recipient site. Skeletal muscle may provide a microenvironment that maintains the inherent features of BAT grafts over a long period of time, which facilitates a reduction in obesity and improvements in glucose homeostasis. [ABSTRACT FROM AUTHOR]

To explore and observe the clinical application effects of face and neck liposuction combined with fat grafting in scar plastic surgery. Used the retrospective research methods, from August 2017 to June 2020, 78 cases of patients with facial and neck scars who were diagnosed and treated in our hospital were selected as the research objects. All the cases were divided into the combination group and control group with 39 cases each groups accorded to the random envelope drawing principle. The control group were given face and neck liposuction treatment, and the combination group were given face and neck liposuction combined with fat transplantation. The treatment were observed for 3 months. There were no significant difference in the pain grading of scars in the combination group compared with the control group after treatment (P>0.05). The beauty weight score and the depth of scar base after treatment in the two groups were lower than before treatment (P<0.05), and thecombination group were lower than the control group (P<0.05). After treatment, the total effective rate of the combination group were 97.4 %, which were higher than 82.1 % of the control group (P<0.05). The incidence of complications such as infection, embolism, hemorrhage and nerve damage in the combination group during treatment were 5.1 %, which were lower than 28.2 % in the control group (P<0.05). The clinical application of face and neck liposuction combined with fat transplantation in scar plastic surgery will not increase the pain of the patient, but can also reduce the depth of the scar base and reduce the occurrence of complications, and improve the beauty of the patient and the overall treatment effect. [ABSTRACT FROM AUTHOR]

Background: Autologous fat grafting has become a popular tool in plastic surgery to solve soft tissue defects and achieve skin rejuvenation, but the volume loss after transplantation remains a disturbing problem. In recent years, some new strategies have improved the outcome to some extent, but the fat graft retention is still far from ideal, so there remains a wide development prospect in this field. Macrophages are closely related to the local microenvironment and tissue regeneration, and their role in fat grafting has been increasingly highlighted. Aims: This article was aimed to review the efficacy, possible mechanisms, and potential application of macrophage regulation on fat grafting, as well as concerns and future perspectives of this filed. Methods: A retrospective review of the published data was conducted. Results: Most studies indicated that up‐regulating M2 macrophages during fat grafting would improve fat retention via promoting neovascularization. M2 macrophages could secrete several pro‐angiogenic factors, accelerate extracellular matrix (ECM) remodeling, and directly function on endothelial cells to encourage vascular expansion. In addition, macrophages could influence the proliferation, apoptosis, and adipogenic differentiation of preadipocytes. Conclusions: During autologous fat grafting, appropriately regulating macrophages may become a promising method to increase fat retention. Nevertheless, the M2 macrophage polarizing agents, treatment opportunity, and contraindications require further discussion. We hope our work could promote more in‐depth studies in this field, and we are looking forward to a standard procedure for the macrophage therapy in clinical practice. [ABSTRACT FROM AUTHOR]

Abstract Background Fat grafting, as a standard treatment for numerous soft tissue defects, remains unpredictable and technique-dependent. Human adipose-derived stem cells (hADSCs) are promising candidates for cell-assisted therapy to improve graft survival. As free-living fat requires nutritional and respiratory sources to thrive, insufficient and unstable vascularization still impedes hADSC-assisted therapy. Recently, cytotherapy combined with modified mRNA (modRNA) encoding vascular endothelial growth factor (VEGF) has been applied for the treatment of ischemia-related diseases. Herein, we hypothesized that VEGF modRNA (modVEGF)-engineered hADSCs could robustly enhance fat survival in a fat graft transplantation model. Methods hADSCs were acquired from lipoaspiration and transfected with modRNAs. Transfection efficiency and expression kinetics of modRNAs in hADSCs were first evaluated in vitro. Next, we applied an in vivo Matrigel plug assay to assess the viability and angiogenic potential of modVEGF-engineered hADSCs at 1 week post-implantation. Finally, modVEGF-engineered hADSCs were co-transplanted with human fat in a murine model to analyze the survival rate, re-vascularization, proliferation, fibrosis, apoptosis, and necrosis of fat grafts over long-term follow-up. Results Transfections of modVEGF in hADSCs were highly tolerable as the modVEGF-engineered hADSCs facilitated burst-like protein production of VEGF in both our in vitro and in vivo models. modVEGF-engineered hADSCs induced increased levels of cellular proliferation and proangiogenesis when compared to untreated hADSCs in both ex vivo and in vivo assays. In a fat graft transplantation model, we provided evidence that modVEGF-engineered hADSCs promote the optimal potency to preserve adipocytes, especially in the long-term post-transplantation phase. Detailed histological analysis of fat grafts harvested at 15, 30, and 90 days following in vivo grafting suggested the release of VEGF protein from modVEGF-engineered hADSCs significantly improved neo-angiogenesis, vascular maturity, and cell proliferation. The modVEGF-engineered hADSCs also significantly mitigated the presence of fibrosis, apoptosis, and necrosis of grafts when compared to the control groups. Moreover, modVEGF-engineered hADSCs promoted graft survival and cell differentiation abilities, which also induced an increase in vessel formation and the number of surviving adipocytes after transplantation. Conclusion This current study demonstrates the employment of modVEGF-engineered hADSCs as an advanced alternative to the clinical treatment involving soft-tissue reconstruction and rejuvenation.

Overaggressive liposuction of the infragluteal region can lead to iatrogenic infragluteal fold deformity and result in esthetic defects in the gluteal contour. We report a case of using autologous fat transplantation to correct severe post-liposuction infragluteal fold deformity. In the process of reconstruction, the patient experienced fat graft overabsorption, fat graft translocation, and gluteal ptosis aggravation. Despite multiple operations, the effect of fat transplantation was limited. In conclusion, severe post-liposuction infragluteal deformity is very difficult to correct. The infragluteal region should be preserved during liposuction to avoid deformity.

Objective To explore the effect of exosomes from human adipose-derived stem cells (hADSCs-exo) on survival of adipose grafts and potential mechanism. Methods From July 2020 to June 2021, the human adipose-derived stem cells (hADSCs) were cultured in vitro and the exosomes were collected, purified and identified. The co-culture system of hADSCs-exo and human umbilical vein endothelial cells (HUVECs) or PBS and HUVECs was established. These co-culture systems were named hADSCs-exo group and PBS group, respectively. The effect of hADSCs-exo on proliferation and migration of HUVECs was evaluated by CCK-8 assay and transwell migration assay. The effect of hADSCs-exo on survival rate and vascularization of fat grafts was investigated by fat transplantation model in nude mice, and the activation of VEGF/AKT signal pathway was detected by western blot experiment and real-time quantitative PCR. Results The co-culture of hADSCs-exo and HUVECs could significantly promote the proliferation and migration of HUVECs in vitro (P<0.01). The survival rate of fat grafts in hADSCs-exo group was significantly higher than that in PBS group, and the hADSCs-exo group had higher vascularization efficiency in vivo experiment. The expression of VEGF/AKT signal pathway in adipose grafts with hADSCs-exo was activated, which was significantly different from that in adipose grafts with PBS only (P<0.01). Conclusion The hADSCs-exo can promote the proliferation and migration of HUVECs by regulating the activity of VEGF/AKT pathway, and then enhance the neovascularization of adipose grafts to improve the fat survival rate. [ABSTRACT FROM AUTHOR]

Subcutaneous adipose tissue (SAT) is recognized as a highly active metabolic and inflammatory tissue. Interestingly, adipose tissue transplantation is widely performed in plastic surgery via lipofilling, yet little is known about the gene alteration of adipocytes after transplantation. We performed an RNA-expression analysis of fat transplants before and after fat transplantation. In C57BL/6 N mice SAT was autologously transplanted. Samples of SAT were analysed before transplantation, 7, and 15 days after transplantation and gene expression profiles were measured. Analysis revealed that lipid metabolism-related genes were downregulated while inflammatory and extracellular matrix related genes were up-regulated 7 and 15 days after transplantation. When comparing gene expression profile 7 days after transplantation to 15 days after transplantation developmental pathways showed most changes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tissue transplantation is the most commonly used treatment in plastic surgery. After transplantation, it is essential for tissue survival to establish blood circulation within the time limit of tissue ischemia resistance. The survival rate and quality of the graft are related to the time of revascularization. OBJECTIVE: To review the regulation and mechanism of promoting early vascularization of fat grafts from different sites with regard to cytokines, adipocytes, exosomes, tissue engineering, and signaling pathway. METHODS: PubMed, Google Scholar, EMbase, CNKI, WanFang, and VIP were searched for relevant literatures published from 1995 to 2020 using the keywords of “fat graft, fat grafting, vascularization, vascularize, cytokines, exosomes, VEGF, ADSCs, EPC, SVF, mechanisms, signal pathway” in English and Chinese, respectively. The articles irrelevant to the content, with low quality or high repeatability were excluded. Finally, 73 articles were selected for review. RESULTS AND CONCLUSION: Various treatments can contribute to early vascularization of fat grafts, including addition of various cytokines or cells, stem cells, selection of fat cells in different parts, relevant signaling pathways, fat pretreatment, tissue engineering, exosomes, etc. Adipose stem cells can regulate angiogenesis and inhibit inflammation through the VEGF-PLCγ-ERK1/ERK2 pathway, and promote early vascularization through the recruitment and differentiation of endothelial progenitor cells. Adipose stem cells from different sites have some differences in vascularization and survival rate. The use of stromal vascular components is an efficient technology to improve the survival of fat grafts. The possible mechanism by which adipose stem cells promote fat graft survival and angiogenesis is that the paracrine products of adipose stem cells can promote vascularization, reduce inflammation, and thereby enhance the volume retention rate of fat grafts. [ABSTRACT FROM AUTHOR]

Remodeling of the extracellular matrix (ECM), which provides structural and biochemical support for surrounding cells, is vital for adipose tissue regeneration after autologous fat grafting. Rapid and high-quality ECM remodeling can improve the retention rate after fat grafting by promoting neovascularization, regulating stem cells differentiation, and suppressing chronic inflammation. The degradation and deposition of ECM are regulated by various factors, including hypoxia, blood supply, inflammation, and stem cells. By contrast, ECM remodeling alters these regulatory factors, resulting in a dynamic relationship between them. Although researchers have attempted to identify the cellular sources of factors associated with tissue regeneration and regulation of the microenvironment, the factors and mechanisms that affect adipose tissue ECM remodeling remain incompletely understood. This review describes the process of adipose ECM remodeling after grafting and summarizes the factors that affect ECM reconstruction. Also, this review provides an overview of the clinical methods to avoid poor ECM remodeling. These findings may provide new ideas for improving the retention of adipose tissue after fat transplantation.

Abstract Background Our previous study proved that nanofat could enhance fat graft survival by promoting neovascularization. Fat extract (FE), a cell-free component derived from nanofat, also possesses proangiogenic activity. Objectives The aim of this study was to investigate whether FE could improve fat graft survival and whether FE and nanofat could work synergistically to promote fat graft survival. The underlying mechanism was also investigated. Methods In the first animal study, human macrofat from lipoaspirate was co-transplanted into nude mice with FE or nanofat. The grafts were evaluated at 2, 4 and 12 weeks post-transplantation. In the second animal study, nude mice were transplanted with a mixture of macrofat and nanofat, followed by intra-graft injection of FE at days 1, 7, 14, 21 and 28 post-transplantation. The grafts were evaluated at 12 weeks post-transplantation. To detect the mechanism by which FE impacts graft survival, the proangiogenic, anti-apoptotic and pro-proliferative activities of FE were analysed in grafts in vivo and in cultured human vascular endothelial cells (HUVECs), adipose-derived stem cells (ADSCs) and fat tissue in vitro. Results In the first animal study, the weights of the fat grafts in the nanofat- and FE-treated groups were significantly higher than those of the fat grafts in the control group. In addition, higher fat integrity, more viable adipocytes, more CD31-positive blood vessels, fewer apoptotic cells and more Ki67-positive proliferating cells were observed in the nanofat- and FE-treated groups. In the second animal study, the weights of the fat grafts in the nanofat+FE group were significantly higher than those of the fat grafts in the control group. In vitro, FE showed proangiogenic effects on HUVECs, anti-apoptotic effects on fat tissue cultured under hypoxic conditions and an ability to promote ADSC proliferation and maintain their multiple differentiation capacity. Conclusions FE could improve fat graft survival via proangiogenic, anti-apoptotic and pro-proliferative effects on ADSCs. FE plus nanofat-assisted fat grafting is a new strategy that could potentially be used in clinical applications.

Objective: We aimed to clarify the changes in apoptosis, proliferation, senescence, and adipogenesis after promoting and inhibiting autophagy in adipose-derived stem cells (ADSCs) by rapamycin and 3-methyladenine in vitro and in vivo. Methods: After rapamycin and 3-methyladenine pretreatment, ADSC autophagy was detected by immunofluorescence for LC3, RT-PCR for ATG genes, and western blotting (WB) for the LC3 II/I and p62 proteins. TUNEL staining, PCR of BAX, and WB of Caspase-3 were preformed to assess ADSC apoptosis. The adipogenesis of ADSCs was evaluated by Oil red O staining and PCR of PPAR-γ. CCK8 assays were conducted to detect proliferation. Senescence was tested by Sa-β-gal staining and PCR of the P16/ 19/21 genes. Moreover, the mass and volume retention rate were determined, and perilipin and CD31 staining were performed in vivo. Results: Rapamycin and 3-methyladenine pretreatment increased and decreased autophagy of ADSCs, respectively, under normal and oxygen-glucose deprivation conditions. Apoptosis and senescence of ADSCs were decreased, and adipogenesis was increased along with the upregulation of autophagy. However, the proliferation of ADSCs was inhibited after either rapamycin or 3-methyladenine pretreatment. In vivo, the volume and mass retention rate and the angiogenesis of the grafts were also improved after rapamycin pretreatment. Conclusions: Rapamycin pretreatment reduced apoptosis, delayed senescence, and promoted adipogenesis of ADSCs. These effects were inhibited by 3-methyladenine, indicating that the changes may be mediated by autophagy. Moreover, the survival rate and angiogenesis of the grafts were increased after upregulation of ADSC autophagy in vivo, which may help improve the efficiency of clinical fat transplantation. No Level Assigned: 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. [ABSTRACT FROM AUTHOR]

Autologous fat transplantation is widely regarded as an increasingly popular method for augmentation or reshaping applications in soft tissue defects. Although the fat transplantation is of simple applicability, low donor site morbidity and excellent biocompatibility, the clinical unpredictability and high resorption rates of the fat grafts remain an inevitable problem. In the sites of fat transplantation, the most essential components are the adipocyte and adipose-derived stem cells (ADSCs). The survival of adipocytes is the direct factor determining fat retention. The efficacy of fat transplantation is reduced by fat absorption and fibrosis due to the inadequate blood flow, adipocyte apoptosis and fat necrosis. ADSCs, a heterogeneous mixture of cells in adipose tissue, are closely related to tissue survival. ADSCs exhibit the ability of multilineage differentiation and remarkable paracrine activity, which is crucial for graft survival. This article will review the recent existing research on the mechanisms of adipocytes and ADSCs in fat transplantation, especially including adipocyte apoptosis, mature adipocyte dedifferentiation, adipocyte browning, ADSCs adipogenic differentiation and ADSCs angiogenesis. The in-depth understanding of the survival mechanism will be extremely valuable for achieving the desired filling effects. [ABSTRACT FROM AUTHOR]

Abstract Background Scarring is the product of natural restoration, yet its treatment remains challenging. Both collagen and fibroblasts are abnormally abundant in scars, leading to scar hyperplasia or contracture. Several clinical studies have reported that wrinkles at the recipient site are reduced, pores are narrowed, pigmentation is decreased, and skin is softened after autologous fat transplantation. In this study, we investigated the ability of autologous chyle fat injection to normalize the fibroblasts and collagen of scar tissue in 80 adult patients with hypertrophic scars resulting from severe burns received more than 1 year previously. Methods The patients underwent autologous chyle fat injection, and scar samples were collected at different time points. Differences in the number of adipocytes before and after chylosis were assessed by cell culture, and changes in the structural organization of the scars were detected via histologic and immunohistochemical analyses. Results After preparation, the chyle fat contained few autologous adipocytes and large amounts of extracellular matrix. Following the injection of chyle fat, the thickness, color, and elasticity of hypertrophic scar tissue tended toward normalization, and patient satisfaction increased. The three adipose tissue donor sites used for the preparation of chyle fat were the abdomen, buttocks, and inner thigh, of which the inner thigh yielded the best therapeutic outcomes. The density and quantity of fibroblasts in the scars decreased following the injection of chyle fat, and the arrangement, quantity, and shape of type III collagen fibers tended toward normalization. After three treatments, the results of immunohistochemical staining showed that type III collagen was significantly less abundant than before treatment. Conclusions Autologous chyle fat transplantation has a good therapeutic effect on hypertrophic scar tissue. The injection of chyle fat into hypertrophic scar tissue reduced the density and quantity of fibroblasts and prompted the arrangement, quantity, and shape of type III collagen to normalize.