Fluid-structure interaction modelling of neighboring tubes with primary cilium analysis

Area of Science:

• Nephrology
• Biophysics
• Computational Biology

Background:

• Primary cilia are crucial cellular organelles involved in mechanotransduction within renal tubules.
• The mechanical forces experienced by cilia are influenced by the surrounding microenvironment.
• Understanding these forces is key to deciphering kidney physiology and disease.

Purpose of the Study:

• To numerically model the impact of adjacent renal tubules on stress experienced by primary cilia.
• To investigate the hypothesis that mechanical coupling between tubules affects cilium base stress.
• To quantify in-plane stresses on a primary cilium under pulsatile flow with a neighboring tubule.

Main Methods:

• Developed a numerical model of two adjacent, elastic, cylindrical renal tubules.
• Utilized COMSOL software for fluid-structure interaction simulation.
• Applied boundary load to the primary cilium to simulate stress at its base.

Main Results:

• In-plane stresses at the primary cilium base were significantly greater with a neighboring tubule present.
• Average stresses increased due to the mechanical coupling and constrained motion of the tubule wall.
• Confirmed the hypothesis that neighboring structures influence cilium mechanosensing.

Conclusions:

• The mechanical constraint imposed by neighboring tubules enhances stress on primary cilia.
• Flow signaling mediated by cilia may be modulated by the degree of tubule wall constraint.
• Simplified model suggests future experiments to explore complex tubule interactions in vivo.