背景:组织工程越来越被视为功能性软骨重建的有希望的途径。然而,体外培养过程中软骨细胞的去分化仍然是组织工程软骨临床转化的障碍。已采用再分化诱导来诱导去分化的软骨细胞回到其原始表型。遗憾的是,这些策略已被证明只是适度有效。
方法:为了探索潜在的机制,对原代软骨细胞(P0)进行RNA转录组测序,去分化软骨细胞(P5),和再分化的软骨细胞(P5,P5的再分化诱导。R).基于多种生物信息学分析,LGR5被鉴定为靶基因。随后,使用P0软骨细胞建立具有LGR5敲低和过表达的稳定细胞系。评估了LGR5敲低或过表达的P1和P5软骨细胞的表型变化,以确定LGR5失调对软骨细胞表型的潜在影响。然后使用生物信息学分析研究调控机制,蛋白质-蛋白质对接,免疫荧光共定位和免疫沉淀。
结果:当前的研究发现LGR5的失调可以显着影响软骨细胞的去分化表型(P5)。LGR5的上调似乎通过增加AKT(p-AKT1)的磷酸化水平来激活PI3K/AKT信号。此外,p-AKT1的增加可能稳定β-catenin,增强Wnt/β-catenin信号的强度,并有助于恢复软骨细胞的去分化表型。
结论:LGR5可通过PI3K/AKT信号通路调节P5传代软骨细胞的表型。
BACKGROUND: Tissue engineering is increasingly viewed as a promising avenue for functional cartilage reconstruction. However, chondrocyte
dedifferentiation during in vitro culture remains an obstacle for clinical translation of tissue engineered cartilage. Re-differentiated induction have been employed to induce dedifferentiated chondrocytes back to their original phenotype. Regrettably, these strategies have been proven to be only moderately effective.
METHODS: To explore underlying mechanism, RNA transcriptome sequencing was conducted on primary chondrocytes (P0), dedifferentiated chondrocytes (P5), and redifferentiated chondrocytes (redifferentiation-induction of P5, P5.R). Based on multiple bioinformatics analysis, LGR5 was identified as a target gene. Subsequently, stable cell lines with LGR5 knocking-down and overexpression were established using P0 chondrocytes. The phenotypic changes in P1 and P5 chondrocytes with either LGR5 knockdown or overexpression were assessed to ascertain the potential influence of LGR5 dysregulation on chondrocyte phenotypes. Regulatory mechanism was then investigated using bioinformatic analysis, protein-protein docking, immunofluorescence co-localization and immunoprecipitation.
RESULTS: The current study found that dysregulation of LGR5 can significantly impact the dedifferentiated phenotypes of chondrocytes (P5). Upregulation of LGR5 appears to activate the PI3K/AKT signal via increasing the phosphorylation levels of AKT (p-AKT1). Moreover, the increase of p-AKT1 may stabilize β-catenin and enhance the intensity of Wnt/β-catenin signal, and help to restore the dedifferentated phenotype of chondrocytes.
CONCLUSIONS: LGR5 can modulate the phenotypes of chondrocytes in P5 passage through PI3K/AKT signaling pathway.