Neuromuscular System Tissue Engineering Notes
Ritu Raman's lab focuses on tissue engineering of biological actuators for applications in medicine and machines.
Mechanical engineers aim to build things that move, generate force, and produce motion, drawing inspiration from natural systems like animals.
Motor control systems, crucial for voluntary mobility, are largely composed of skeletal muscle and motor neurons.
Muscle cells, or fibers, contain actin and myosin proteins that slide against each other to contract the fiber, generating force.
Motor neurons, located in the spinal cord, connect to muscle cells forming a motor unit, enabling precise tuning of muscle activation.
Building motor control systems can enhance understanding of human biology and aid in restoring mobility lost due to disease or injury.
Engineered tissues can power robots, with a focus on developing methods to fabricate multicellular systems with reproducible morphology and function.
Muscle tissues are created by mixing cells in a prepolymer hydrogel solution that mimics the extracellular matrix.
Stretching these tissues aligns the fibers, controlling contractility, and electrical stimulation can induce pulsatile movement.
Light stimulation using optogenetic techniques offers a noninvasive alternative to electrical stimulation for controlling muscle contraction.
Repeated light stimulation modulates muscle strength, endurance, and healing after trauma.
Volumetric muscle loss injuries, where a significant portion of muscle is damaged, pose a challenge due to impaired regeneration.
Targeted muscle stimulation accelerates recovery from traumatic injuries by driving the growth of new nerves and vasculature into the graft.
Muscle contraction drives innervation and vascularization.
Muscle secreted factors are neurotrophic.
Mechanical stimulation enhances motor neuron growth and axon length, indicating that muscle-to-nerve signaling is both biochemical and mechanical.
Lab is developing methods for magnetically actuating tissues to pattern innervation and guide morphology and function of neuromuscular tissues.
Biological tissues can serve as functional components of machines or robots, especially in dynamic and unpredictable environments.
Robots powered by muscle offer potential for dexterity, precision, and adaptability.
The lab focuses on designing, modeling, and manufacturing muscle-powered robots capable of predictable function.
Challenges remain in replicating the complexity of biological architectures, such as multi-oriented muscles that enable multi-degree of freedom motion.
Two-dimensional muscles, with precisely controlled architecture, can mimic tissues like the iris, enabling spatial patterning of forces.
Three-dimensional spring-like skeletons enhance the reproducibility and control of muscle contraction in robots.
Biohybrid muscle-tendon units improve force transmission and reduce stress concentrations in robotic systems.
Active and gentle mixing of bioinks during 3D bioprinting ensures even cell distribution and viability in printed tissues using magnetic-based system.
In situ monitoring techniques are being developed to control print quality in real-time during automated fabrication.
The lab is investigating human neuromuscular model systems to understand the impact of exercise on diseases and pathologies, as well as developing closed-loop control for actuator contraction and lifetime.