Conventional Nanofat and SVF/ADSC-Concentrated Nanofat: A Comparative Study on Improving Photoaging of Nude Mice Skin

Background: Nanofats could improve photoaging. Stromal vascular fraction (SVF) and adipose-derived stem cells (ADSCs) may play pivotal roles. However, SVFs and ADSCs in nanofats processed by conventional methods cannot be enriched. Some researchers have found that after centrifugation, the SVF/ADSC density increases from top to bottom. Objectives: The authors hypothesized that centrifugation can be used to obtain SVF/ADSC-concentrated nanofats that are superior to conventional nanofats in improving the photoaging of skin. Methods: After a photoaging model was successfully established in nude mice, the back of each mouse was divided into 4 areas and randomly injected with conventional nanofat, centrifuged nanofat (either the middle or lower layer of centrifuged nanofat), or normal saline. Wrinkles, dermis thickness, dermal collagen content, and elastic fiber morphology were measured and compared at weeks 4 and 8. Results: Compared with the wrinkles in the physiological saline injection areas, the wrinkles in the areas injected with the 3 nanofats (lower and middle layers of centrifuged nanofat and conventional nanofat) were significantly reduced. All 3 nanofat groups showed increased dermal thickness, increased collagen content, and a more regular distribution of elastic fibers compared with the saline injection areas. Conclusions: The study established the efficacy of nanofats in improving photoaging by reducing wrinkles and increasing the thickness of dermal collagen, making nanofats a promising novel treatment for photoaging. The SVF/ADSC-concentrated nanofats exhibited the most improvement.