PTEN Reduces BMP9-Induced Osteogenic Differentiation Through Inhibiting Wnt10b in Mesenchymal Stem Cells

Area of Science:

• Biochemistry
• Cell Biology
• Molecular Biology

Background:

• Bone morphogenetic protein 9 (BMP9) is a potent osteogenic cytokine.
• PTEN and Wnt10b are known regulators of osteogenesis, but their interaction with BMP9 is unclear.

Purpose of the Study:

• To investigate the relationship between PTEN and Wnt10b in BMP9-induced osteogenesis in mesenchymal stem cells (MSCs).
• To elucidate the molecular mechanisms by which PTEN influences BMP9's osteogenic potential via Wnt10b.

Main Methods:

• Utilized mesenchymal stem cells (MSCs) treated with BMP9.
• Manipulated PTEN and Wnt10b expression (knockdown/inhibition) and measured osteogenic markers, ALP activity, and mineralization.
• Investigated protein-protein interactions (p-CREB, p-Smad1/5/9) and their binding to the Wnt10b promoter using molecular biology techniques.

Main Results:

• BMP9 inhibits PTEN but increases Wnt10b expression in MSCs.
• PTEN suppresses BMP9-induced osteogenesis, an effect reversed by Wnt10b.
• PTEN reduces Wnt10b expression by disrupting the interaction between CREB and BMP/Smad signaling at the Wnt10b promoter.

Conclusions:

• PTEN negatively regulates BMP9-induced osteogenesis, partly by decreasing Wnt10b expression.
• The mechanism involves PTEN interfering with p-CREB and p-Smad1/5/9 binding to the Wnt10b promoter.
• Findings reveal a novel regulatory pathway involving PTEN, Wnt10b, CREB, and BMP/Smad signaling in osteogenesis.