Biomedical Engineering for Muscle Research


Muscle as a biomechatronic system

Muscle disorders are characterized by a decay in force production and associated weakness compromising mobility in organisms. The causes of inherited and acquired myopathies are diverse since muscle force is the result of a complex activation cascade within the organ that comprises activation of ion channels, calcium regulation and motor protein interaction. Additionally, muscle is not only characterized by its active but also by passive elasticity components, and both of them set biomechanics of muscle.

In collaboration with the Institute of Neuropathology and within the DFG research group FOR1228 (Prof. Schröder), we investigate the molecular effects of inherited mutations of the myofibrillar cytoskeleton (that links the contractile elements and preserves the motor protein lattice) on the biomechanics of skeletal muscle. The identification of specific mechanisms resulting in the progression of the diseases is a major goal since this would allow to identify putative targets for future therapies. While the neruopathologists provide medical input, we focus on developing and application of biomedical engineering and process technology expertise.

Figure: Muscle biomechanics and Force Transducer technologies development. A, skeletal muscle overall biomechanics is set by active motor proteins  and passive elastic cytoskeleton elements. B, muscle biomechanics is also set at the levels of different organ scales from the whole muscle down to cellular and subcellular compartments. Pathologies that are confined to one organ scale might, e.g., be partially compensated for at upper scales. C, process engineering, development and optimization of novel force transducer technologies and devices  at the Institute bringing together expertise from mechatronics, metrology and sensory technologies.  Such novel devices are then validated versus manual old technologies used in medical research (D) before introducing them as a novel research tool to life science studies.

Biomechanics engineering

Muscle function testing on various organ scales (whole muscle, muscle fibre bundles or single fibres, see figure) still have to be performed under elaborate manual skills including isolation of single cells from muscle tissue from patient biopsies or animal models and attaching them to a so-called 'force transducer'. Muscle physiology tests often are reflected by measuring force responses to incubation in different solutions.

One of the main engineering and biotechnology challenges is given by automation and optimization of such devices using advanced mechatronics, metrology and sensor technology approaches. Our biomechanics group thus, besides biomedical experimentation, also has a strong focus on developing novel force-transducer technologies to join automation robotics as well as parallelization and analysis routines to increase the throughput, reliability and reproducibility of biomechanical experiments on skeletal muscle in biomedical research.

Literature:

  • Cecchi G, Griffiths PJ, Taylor S (1986). Stiffness and force in activated frog skeletal muscle fibres. Biophys J 49: 437-451.
  • MacIntosh BR, Esau SP, Holash RJ, Fletcher JR (2011). Procedures for rat in situ skeletal muscle contractile properties. J Vis Exp 56: e3167.