RESUMO
BACKGROUND/PURPOSE: Our previous work has demonstrated that rat bone marrow stem cells (BMSCs) can transdifferentiate into α-amylase-producing cells after coculture with rat submandibular gland acinar cells. These transdifferentiated cells may be used for regeneration of damaged salivary gland. The purpose of this study was to investigate the global gene expression of rat BMSCs cocultured with rat submandibular gland acinar cells and the factors inducing this transdifferentiation. METHODS: Rat BMSCs were indirectly cocultured with rat submandibular gland acinar cells by using the double chamber system for 5 and 10 days. The global gene expression of BMSCs during transdifferentiation into acinar cells was investigated by microarray analysis. RESULTS: A total of 45,018 probes were used and 41,012 genes were detected. After coculture for 5 days, 1409 genes were upregulated more than twofold and 1417 genes were downregulated more than twofold (p<0.005). Moreover, after coculture for 10 days, 1356 genes were upregulated more than twofold and 1231 genes were downregulated more than twofold (p<0.005). Bone morphogenetic protein (BMP)-6 was one of the top-ranked upregulated genes. The hub genes were interleukin-6 and CCAAT/enhancer-binding protein ß (CEBPB) in the early and late response gene groups, respectively. CONCLUSION: This is believed to be the first study on the global gene expression of rat BMSCs cocultured with rat acinar cells. Many genes related to the function of salivary acinar cells such as those responsible for the production of α-amylase protein were upregulated and many genes related to the differentiation of BMSCs into adipocytes and osteoblasts were downregulated. In addition, BMP-6 gene was found to be highly upregulated. We proposed that three target genes, BMP-6, interleukin-6 and CEBPB, play important roles in the transdifferentiation of BMSCs into acinar cells, and are worthy of further investigation.
Assuntos
Células Acinares/citologia , Células da Medula Óssea/citologia , Proteína Morfogenética Óssea 6/genética , Regulação da Expressão Gênica no Desenvolvimento , Análise em Microsséries/métodos , RNA/genética , Glândula Submandibular/citologia , Células Acinares/metabolismo , Animais , Animais Recém-Nascidos , Células da Medula Óssea/metabolismo , Proteína Morfogenética Óssea 6/biossíntese , Diferenciação Celular , Transdiferenciação Celular , Técnicas de Cocultura , Ratos , Ratos Wistar , Glândula Submandibular/metabolismoRESUMO
BACKGROUND/PURPOSE: Hypofunction of the salivary glands can substantially affect quality of life. Current treatments for salivary hypofunction are of limited effectiveness. Although the implantation of functional salivary gland tissue from autologous glandular cells represents a possible physiologic solution to this problem, tissue engineering of salivary glands would require the generation of a great number of acinar cells (ACs). The purpose of this study was to investigate the feasibility of transdifferentiation of bone marrow stem cells (BMSCs) into functional ACs using a co-culture system. METHODS: BMSCs were isolated from adult rats and co-cultured with rat parotid ACs using a double chamber system. The transdifferentiation of BMSCs was evaluated by immunocytochemical analysis of alpha-amylase, which has unique functional expression in ACs. RESULTS: Expression of alpha-amylase, indicating successful transdifferentiation of BMSCs into ACs, was found in 30% of BMSCs after co-culturing for 1 week, and in 50% after co-culturing for 2 and 3 weeks. CONCLUSION: This study has demonstrated the potential of rat BMSCs to transdifferentiate into ACs, and support the feasibility of application of BMSCs in salivary gland tissue engineering.