Sonoepigenetic Modification Mechanoprimes Early Osteogenic Commitment in Mesenchymal Stem Cells

Area of Science:

• Cell Biology
• Biophysics
• Biochemistry

Background:

• Cells maintain homeostasis by integrating external signals through complex nuclear mechanotransduction pathways.
• The precise mechanisms by which extracellular cues reach the nucleus and influence cell fate are not fully understood.
• Current models often emphasize direct cytoskeletal transmission of signals, potentially overlooking other key regulatory elements.

Purpose of the Study:

• To investigate the role of second messenger signaling in nuclear mechanotransduction.
• To elucidate the contribution of calcium (Ca2+) and cyclic adenosine monophosphate (cAMP) crosstalk to cellular responses to mechanical stimuli.
• To explore the potential of targeted mechanostimulation for directing cell differentiation.

Main Methods:

• Utilized high-frequency (10 MHz) nanomechanostimulation to probe cellular responses.
• Analyzed nuclear chromatin dynamics and fluctuations in response to mechanical stimuli.
• Investigated the spatiotemporal interplay between calcium (Ca2+) and cyclic adenosine monophosphate (cAMP).

Main Results:

• Nuclear chromatin response to mechanostimulation is primarily governed by the spatiotemporal dynamics of Ca2+ and cAMP crosstalk.
• This cellular conditioning represents an adaptive response, termed 'mechanopriming'.
• Brief daily exposure (10 minutes) to nanomechanostimulation induced osteogenic differentiation in mesenchymal stem cells within three days, without requiring osteogenic factors.

Conclusions:

• Bidirectional crosstalk between Ca2+ and cAMP is a critical regulator of nuclear mechanotransduction.
• Nanomechanostimulation can induce adaptive cellular responses and 'mechanopriming'.
• Targeted mechanical stimulation offers a novel, factor-free approach for directing stem cell lineage commitment, specifically toward osteogenesis.