Transplantation of Cold-Stimulated Subcutaneous Adipose Tissue Improves Fat Retention and Recipient Metabolism.

Background: Induction of beige fat for grafting is an emerging transplantation strategy. However, safety concerns associated with pharmaceutical interventions limit its wider application. Moreover, because beige fat is a special type of fat with strong metabolic functions, its effect on the metabolism of recipients after grafting has not been explored in the plastic surgery domain.

Objectives: The aim of this study was to explore whether cold-induced inguinal white adipose tissue (iWAT) transplantation has a higher retention rate and beneficial effects on recipient metabolism.

Methods: C57/BL6 mice were subjected to cold stimulation for 48 hours to induce the browning of iWAT and harvested immediately. Subsequently, each mouse received a transplant of 0.2 mL cold-induced iWAT or normal iWAT. Fat grafts and recipients' iWAT, epididymal adipose tissue, and brown adipose tissue were harvested at 8 weeks after operation. Immunofluorescence staining, real-time polymerase chain reaction, and western blot were used for histological and molecular analysis.

Results: Cold-induced iWAT grafting had a higher mean [standard error of the mean] retention rate (67.33% [1.74%] vs 55.83% [2.94%], P < .01) and more satisfactory structural integrity than normal iWAT. Histological changes identified improved adipose tissue homeostasis after cold challenge, including abundant smaller adipocytes, higher levels of adipogenesis, angiogenesis, and proliferation, but lower levels of fibrosis. More importantly, cold-induced iWAT grafting suppressed the inflammation of epididymal adipose tissue caused by conventional fat grafting, and activated the glucose metabolism and thermogenic activity of recipients' adipose tissues.

Conclusions: Cold-induced iWAT grafting is an effective nonpharmacological intervention strategy to improve the retention rate and homeostasis of grafts. Furthermore, it improves the adverse effects caused by traditional fat grafting, while also conferring metabolic benefits.