Bioactive decellularized adipose matrix prepared using a rapid, nonchemical/enzymatic method for adipogenesis.

Recent developments in the field of regenerative surgeries and medical applications have led to a renewed interest in adipose tissue-enriched mesenchymal stem cell scaffolds. Various advantages declared for the decellularized adipose matrix (DAM) have caused its extensive use in the transfer of stem cells or growth factors for soft tissue regeneration induction. Meanwhile, the long-term application of detergents toward DAM regeneration has been assumed as a risky obstacle in this era. Herein, a rapid, mechanical protocol was developed to prepare DAM (M-DAM) without chemicals/enzymes and was comprehensively compared with the ordinary DAM (traditional chemical method). Accordingly, this method could effectively hinder oils and cells, sustain the structural and biological elements, and contain a superior level of collagen content. In addition, more protein numbers, as well as higher basement membrane elements, glycoproteins, and extracellular matrix-related proteins were detected in the regenerated M-DAM. Also, superior adipogenesis and angiogenesis proteins were distinguished. The noncytotoxicity of the M-DAM was also approved, and a natural ecological niche was observed for the proliferation and differentiation of stem cells, confirming its great potential for vascularization and adipogenesis in vivo. The suggested technique could effectively prepare the modified DAM in variant constructions of tablets, powders, emulsions, hydrogels, and different three-dimensional-printed structures. Hence, this rapid, mechanical process can produce bioactive DAM, which has the potential to be widely used in various research fields of regenerative medicine.

Meta-Analysis of the Oncological Safety of Autologous Fat Grafting After Breast Cancer on Basic Science and Clinical Studies.

BACKGROUND: The purpose of the present study was to comprehensively evaluate the oncological safety of autologous fat grafting after breast cancer by combining experimental and clinical studies. METHODS: All studies published before August 2021 were collected by searching PubMed, Cochrane, Embase, Web of Science, SINOMED, and China National Knowledge Infrastructure. After screening the research and extracting the data, RevMan was used to perform the meta-analysis. RESULTS: Five basic science studies and 26 clinical studies, involving a total of 10,125 patients, were eventually included. In the basic science studies, adipose-derived stem cells promoted breast cancer growth, but fat grafting and adipose-derived stem cells plus fat grafting were not associated with breast cancer growth. An overall analysis of clinical studies showed that autologous fat grafting does not increase the risk of breast cancer recurrence. Subgroup analyses indicated that autologous fat grafting did not increase the risk of breast cancer recurrence in Asian or Caucasian patients, in patients undergoing breast-conserving surgery or modified radical mastectomy, in patients with in situ carcinomas or invasive carcinomas, or in patients undergoing postoperative radiotherapy. CONCLUSION: This study combined experimental and clinical studies to conclude that autologous fat grafting does not increase the risk of breast cancer recurrence. However, the experimental results suggest that adipose-derived stem cells should be used with caution after breast cancer surgery. LEVEL OF EVIDENCE III: 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 .

Innovative Application of Three-Dimensional-Printed Breast Model-Aided Reduction Mammaplasty.

Symptomatic macromastia places a severe physical and psychological burden on patients. Reduction mammaplasty is the primary treatment; however, conventional surgery may lead to postoperative nipple-areolar complex necrosis due to damage to the dominant supplying arteries. In this study, we designed and fabricated an innovative, three-dimensional-printed breast vascular model to provide surgical guidance for reduction mammaplasty. Preoperative computed tomography angiography scanning data of patients were collected. The data were then processed and reconstructed using the E3D digital medical modeling software (version 17.06); the reconstructions were then printed into a personalized model using stereolithography. The three-dimensional-printed breast vascular model was thus developed for individualized preoperative surgical design. This individualized model could be used to intuitively visualize the dominant supplying arteries' spatial location in the breasts, thereby allowing effective surgical planning for reduction mammaplasty. The three-dimensional-printed breast vascular model can therefore provide an individualized preoperative design and patient education, avoid necrosis of the nipple-areolar complex, shorten operation duration, and ensure safe and effective surgery in patients.

Severe Vascular Complications Caused by Facial Autologous Fat Grafting: A Critical Review.

BACKGROUND: Vascular embolism is the most severe complication after autologous fat grafting. With a worldwide increase in fat grafting, there has been a rise in severe vascular complications, such as ophthalmic artery embolism, cerebral artery embolism, and even death. This article aims to review the role of fat in causing severe vascular complications and the association between fat grafting and severe vascular complications. METHODS: A critical review was conducted by appraising the cases of severe vascular complications associated with facial fat grafting reported globally. Repeated cases that were reported in multiple publications were further screened. RESULTS: The final search yielded 50 publications in English that met the inclusion criteria for review. A total of 113 cases of fat-induced severe vascular complications in the literature were identified. The number of cases reported yearly has increased over time, with even more significant increases since 2010. The glabella and temple are the most common sites of severe vascular complications described in the literature. In addition, only one case of ophthalmic artery embolism and one case of cerebral artery embolism have been treated successfully. CONCLUSIONS: Given the increase in reported cases of severe vascular complications, both doctors and patients should pay careful attention to the risks of facial fat grafting. Because of the unclear mechanism of vascular embolism and the lack of guidelines for prevention and treatment, the effective cure rate is unsatisfactory. We propose that preventing vascular embolism is a priority in fat grafting and that timely, multidisciplinary treatment should be performed when severe vascular complications occur. It is necessary in future studies to explore the mechanisms of vascular embolism and effective treatment strategies to promote the development of fat grafting.

Decellularized adipose matrix provides an inductive microenvironment for stem cells in tissue regeneration.

Stem cells play a key role in tissue regeneration due to their self-renewal and multidirectional differentiation, which are continuously regulated by signals from the extracellular matrix (ECM) microenvironment. Therefore, the unique biological and physical characteristics of the ECM are important determinants of stem cell behavior. Although the acellular ECM of specific tissues and organs (such as the skin, heart, cartilage, and lung) can mimic the natural microenvironment required for stem cell differentiation, the lack of donor sources restricts their development. With the rapid development of adipose tissue engineering, decellularized adipose matrix (DAM) has attracted much attention due to its wide range of sources and good regeneration capacity. Protocols for DAM preparation involve various physical, chemical, and biological methods. Different combinations of these methods may have different impacts on the structure and composition of DAM, which in turn interfere with the growth and differentiation of stem cells. This is a narrative review about DAM. We summarize the methods for decellularizing and sterilizing adipose tissue, and the impact of these methods on the biological and physical properties of DAM. In addition, we also analyze the application of different forms of DAM with or without stem cells in tissue regeneration (such as adipose tissue), repair (such as wounds, cartilage, bone, and nerves), in vitro bionic systems, clinical trials, and other disease research.