Microalgae empower skeletal muscle via increased force production and viability.

Engineered skeletal muscle holds potential for tissue engineering and biohybrid robotics applications. However, current strategies face challenges in enhancing force generation while maintaining stability and scalability of the muscle, largely due to insufficient oxygenation and limited nutrient delivery. In this study, we present an engineering approach to address these limitations by coculturing Chlamydomonas reinhardtii (C. reinhardtii), a photosynthetic unicellular green microalga, with C2C12 myoblasts in a hydrogel matrix. Leveraging the photosynthetic activity of C. reinhardtii, our microalgae-empowered muscle (MAM) constructs exhibited superior contractility and almost three times higher active force generation compared to conventional muscle constructs. MAM showed higher cellular viability and reduced tissue damage, attributed to in situ oxygenation and nutrient supply provided by microalgal photosynthesis. In addition, improved myotube alignment was observed in MAM, which contributed to enhanced force generation. Our findings showcase the potential of photosynthetic microalgae as a functional component in engineered skeletal muscle, offering a solution to longstanding challenges in muscle engineering.