Impact of human visceral and glutealfemoral adipose tissue transplant on glycemic control in a mouse model of diet-induced obesity

Erythrocyte Membrane Coating Alleviate Immune Response and Promoted Adipogenesis in Adipose Matrix

Xenotransplantation of acellular adipose matrix (AAM) has come to prominence as an intriguing option for soft tissue reconstruction. However, the presence of immunogenic antigens within AAM can trigger unfavorable immune reactions, leading to inadequate in vivo regeneration outcomes. Therefore, the development of advanced technology capable of modulating immune responses is crucial for the therapeutic implementation of AAM xenografts. In this work, an innovative technique is created to bypass the immune system by covering the surface of both AAM and Arg-Gly-Asp (RGD) peptide-modified AAM xenografts with autologous red blood cell (RBC) membrane. The RBC membrane coating remained persistent and exhibited no significant decline even after 21 days. Moreover, it effectively reduced the expression of antigen major histocompatibility complex class 1 (MHC1) on the AAM surface. Following xenogeneic transplantation, the RBC-coated xenografts demonstrated increased expression of the adipogenic factor PPAR-γ, Adipoq, Fabp4, Fasn, and Plin1 and higher numbers of adipocytes. In addition, they exhibited decreased expression of immunological factors, including IL-6, IL-2, IFN-γ, and TNF-α, and fewer inflammatory cells. These findings indicate that RBC membrane coating successfully suppressed immune responses and promoted increased adipogenesis in AAM xenografts. Therefore, AAM camouflage coating with RBC has a lot of potential as a biomaterial for soft tissue reconstruction in clinical settings.

Metabolic effects of lipectomy and of adipose tissue transplantation

OBJECTIVE

The goal of this study was to review the metabolic effects of fat transplantation.

METHODS

Fat (adipose tissue [AT]) transplantation has been performed extensively for many years in the cosmetic reconstruction industry. However, not all fats are equal. White, brown, and beige AT differ in energy storage and use. Brown and beige AT consume glucose and lipids for thermogenesis and, theoretically, may provide greater metabolic benefit in transplantation. Here, the authors review the metabolic effects of AT transplantation.

RESULTS

Removal of subcutaneous human AT does not have beneficial metabolic effects. Most studies find no benefit from visceral AT transplantation and some studies report harmful effects. In contrast, transplantation of inguinal or subcutaneous AT in mice has positive effects. Brown AT transplant studies have variable results depending on the model but most show benefit.

CONCLUSIONS

Many technical improvements have optimized fat grafting and transplantation in cosmetic surgery. Transplantation of subcutaneous AT has the potential for significant metabolic benefits, although there are few studies in humans or using human AT. Brown AT transplantation is beneficial but not readily feasible in humans thus ex vivo "beiging" may be a useful strategy. AT transplantation may provide clinical benefits in metabolic disorders, especially in the setting of lipodystrophy.

Transplantation of fat tissues and iPSC-derived energy expenditure adipocytes to counteract obesity-driven metabolic disorders: Current strategies and future perspectives

Several therapeutic options have been developed to address the obesity epidemic and treat associated metabolic diseases. Despite the beneficial effects of surgery and drugs, effective therapeutic solutions have been held back by the poor long-term efficiency and detrimental side effects. The development of alternative approaches is thus urgently required. Fat transplantation is common practice in many surgical procedures, including aesthetic and reconstructive surgery, and is a budding future direction for treating obesity-related metabolic defects. This review focuses on adipose tissue transplantation and the recent development of cell-based therapies to boost the mass of energy-expenditure cells. Brown adipocyte transplantation is a promising novel therapy to manage obesity and associated metabolic disorders, but the need to have an abundant and relevant source of brown fat tissue or brown adipocytes for transplantation is a major hurdle to overcome. Current studies have focused on the rodent model to obtain a proof of concept of a tissue-transplantation strategy able to achieve effective long-term effects to reverse metabolic defects in obese patients. Future perspectives and opportunities to develop innovative human fat tissue models and 3D engineered hiPSC-adipocytes are discussed.