Cartilage tissue formation from human adipose‑derived stem cells via herbal component (Avocado/soybean unsaponifiables) in scaffold‑free culture system

Background: The use of stem cells, growth factors, and scaffolds to repair damaged tissues is a new idea in tissue engineering. The aim of the present study is the investigation of Avocado/soybean (A/S) effects on chondrogenic differentiation of human adipose‑derived stem cells (hADSCs) in micromass culture to access cartilage tissue with high quality. Materials and Methods: In this an experimental study After hADSCs characterization, chondrogenic differentiation was induced using transforming growth factor beta 1 (TGF‑β1) (10 ng/ml) and different concentrations (5, 10, and 20 µg/ml) of A/S in micromass culture. The efficiency of A/S on specific gene expression (types I, II, and X collagens, SOX9, and aggrecan) was evaluated using quantitative polymerase chain reaction. In addition, histological study was done using hematoxylin and eosin and toluidine blue staining all data were analyzed using one‑way analysis of variance (ANOVA) and P ≤ 0.05 was considered to be statistically significant. Results: The results of this study indicated that A/S can promote chondrogenic differentiation in a dose‑dependent manner. In particular, 5 ng/ml A/S showed the highest expression of type II collagen, SOX9, and aggrecan which are effective and important markers in chondrogenic differentiation. In addition, the expression of types I and X collagens which are hypertrophic and fibrous factors in chondrogenesis is lower in present of 5 ng/ml A/S compared with TGF‑β1 group (P ≤ 0.05). Moreover, the sulfated glycosaminoglycans in the extracellular matrix and the presence of chondrocytes within lacuna were more prominent in 5 ng/ml A/S group than other groups. Conclusion: It can be concluded that A/S similar to TGF‑β1 is able to facilitate the chondrogenic differentiation of hADSCs and do not have adverse effects of TGF‑β1. Thus, TGF‑β1 can be replaced by A/S in the field of tissue engineering.