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 limits its wider application. Moreover, as a special type of fat with strong metabolic functions, the effect of metabolism of recipients after beige fat grafting has not been explored in plastic surgery domain.

OBJECTIVES: To explore whether cold-induced inguinal white adipose tissue(iWAT) transplantation has a higher retention rate and beneficial effects on recipient metabolism.

METHODS: The mice were subjected to cold stimulation for 48 hours to induce the browning of iWAT and harvested immediately. Subsequently, each C57/BL6 mouse received 0.2 ml cold-induced iWAT or normal iWAT transplantation. Fat grafts and recipients' iWAT, epididymal adipose tissue (epiWAT) and brown adipose tissue (BAT) were harvested at 8 weeks after operation. Immunofluorescence staining, real-time PCR and western blot were used for histological and molecular analysis.

RESULTS: Cold-induced iWAT grafting has a higher retention rate (67.33%±1.74% vs. 55.83% ± 2.94%, P < 0.01) and more satisfactory structural integrity. Histological changes identified the better 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 epiWAT caused by conventional fat grafting, and activated the glucose metabolism and thermogenic activity of recipients' adipose tissues.

CONCLUSIONS: Cold-induced iWAT grafting was an effective non-pharmacological intervention strategy to improve the retention rate and grafts' homeostasis. Furthermore, it improved the adverse effects caused by traditional fat grafting, but bring metabolic benefits.