[The cellular plasticity of human adipocytes]

Human adipose tissue is a rich source of stem cells and differentiated cells, such as mature adipocytes. While adipose-derived stem cells (ASCs) are well-established in regenerative medicine, the potential of mature adipocytes to dedifferentiate into progenitor-like cells remains less explored. Prior research has shown that ASCs can differentiate into multiple lineages, including adipogenic, osteogenic, and chondrogenic cells. However, the ability of mature adipocytes to reverse their differentiation state and regain multipotency is not fully understood. This uncertainty drives the need to investigate whether mature adipocytes can dedifferentiate into fibroblast-like cells in vitro. No prior work has resolved whether dedifferentiated adipocytes (DA) can function similarly to ASCs in terms of proliferation and differentiation potential. This gap motivated the current study to explore the dedifferentiation process and assess the functional equivalence of DA and ASCs.

The aim of this study is to determine whether mature human adipocytes can dedifferentiate into fibroblast-like cells in vitro and whether these dedifferentiated adipocytes (DA) can serve as viable seed cells for tissue engineering. The specific problem addressed is the lack of clarity regarding the functional potential of dedifferentiated adipocytes compared to established adipose-derived stem cells (ASCs). The motivation stems from the need to expand the pool of available seed cells for tissue engineering applications. By comparing DA with ASCs, the study seeks to evaluate their similarities in terms of proliferation rates, cell surface markers, and differentiation capabilities. The researchers propose that DA may have comparable regenerative potential to ASCs. This could lead to new strategies for adipose tissue engineering. The study also aims to assess whether DA express stem cell-related surface proteins, which could indicate their suitability as seed cells.

The study used human fat aspirates to isolate mature adipocytes and adipose-derived stem cells (ASCs). Mature adipocytes were cultured using the ceiling adherent method to induce dedifferentiation into fibroblast-like dedifferentiated adipocytes (DA). Cell morphology was monitored throughout the dedifferentiation process. Cell viability was assessed using MTT chromatometry, and growth curves were generated from these measurements. Flow cytometry was used to compare the expression of cell surface markers between DA and ASCs. Adipogenic potential was evaluated using oil red O staining to detect lipid droplets. Osteogenic potential was assessed using alizarin bordeaux staining to detect calcium mineralization. Chondrogenic potential was evaluated using alcian blue staining to detect cartilage matrix formation. These methods allowed the researchers to compare DA and ASCs across multiple biological parameters.

Mature adipocytes successfully dedifferentiated into fibroblast-like dedifferentiated adipocytes (DA) in vitro. MTT chromatometry showed that DA and ASCs had comparable reproductive activity, with no significant difference in growth rates. Flow cytometry revealed that both DA and ASCs expressed HLA-ABC, CD29, and CD44 but did not express CD45, CD34, or CD106. After two weeks of adipogenic differentiation, both DA and ASCs showed lipid droplet formation as detected by oil red O staining. After two weeks of osteogenic differentiation, calcium salt mineralization was detected in DA and ASCs using alizarin bordeaux staining. After two weeks of chondrogenic differentiation, cartilage matrix formation was observed in DA and ASCs using alcian blue staining. These findings suggest that DA have strong adipogenic, osteogenic, and chondrogenic potential. DA express stem cell-related surface proteins, indicating their similarity to ASCs in terms of regenerative capacity.

The authors propose that mature human adipocytes can dedifferentiate into fibroblast-like dedifferentiated adipocytes (DA) in vitro. DA exhibit strong reproductive activity and differentiation potential comparable to adipose-derived stem cells (ASCs). The expression of stem cell-related surface proteins in DA suggests their potential as seed cells for adipose tissue engineering. The study did not claim that DA are superior to ASCs but demonstrated their functional equivalence in terms of proliferation and differentiation. The findings suggest that DA may serve as an alternative source of seed cells in tissue engineering applications. The authors did not infer broader implications beyond the observed similarities between DA and ASCs. The study does not claim that DA will replace ASCs but highlights their potential as a viable option in regenerative medicine.