Data on calcium increases depending on stretch in dystrophic cardiomyocytes

Area of Science:

• Cardiology
• Cell Biology
• Biophysics

Background:

• Duchenne muscular dystrophy (DMD) leads to cardiomyopathy.
• Altered ion handling in mdx cardiomyocytes contributes to disease progression.
• Previous studies identified constitutive cation entry and TRPV2 channel involvement in mdx cardiomyocytes under stretch.

Purpose of the Study:

• To quantify intracellular calcium concentration ([Ca2+]i) in wild-type (WT) and mdx ventricular cardiomyocytes.
• To compare [Ca2+]i at rest and under axial stretch, mimicking physiological ventricular filling.
• To provide data on calcium dynamics in a model of dystrophic cardiomyopathy.

Main Methods:

• Isolated ventricular cardiomyocytes from WT and mdx mice were used.
• Intracellular calcium ([Ca2+]i) was measured using the Ca2+ dye fluo-8.
• Axial stretch was applied using a carbon microfibers technique.
• Perfusion protocol involved calcium-free Tyrode solution followed by 1.8 mM Ca2+ Tyrode solution.

Main Results:

• Intracellular calcium concentration ([Ca2+]i) variations were significantly higher in mdx cardiomyocytes compared to WT.
• This elevated [Ca2+]i was observed under both resting and axial stretch conditions.
• The data quantifies calcium handling differences relevant to dystrophic cardiomyopathy.

Conclusions:

• mdx cardiomyocytes exhibit altered intracellular calcium handling.
• Elevated [Ca2+]i in mdx cardiomyocytes may contribute to the pathophysiology of dystrophic cardiomyopathy.
• These findings provide crucial data for understanding cardiac dysfunction in DMD.