di , 20/12/2023

Research into replicating the intricate design and adaptability of natural tissues through tissue engineering, has been ongoing for decades. A key challenge lies in understanding and controlling the mechanical forces to which cells are subjected to in their environment. Tissues are by nature not rigid or isolated structures; they must possess the structural and functional flexibility to adapt to changing chemical and physical conditions in their operating environment. A particularly important factor is to understand how tissues respond to variations in biochemical, electrical, and mechanical forces that determine the relationships between tissue components and their dynamic functioning.

While physiologist have made significant progress in decoding biochemical and electrical signals in multicellular systems, the field of mechanical signals remains relatively unexplored. However, a groundbreaking discovery looms on the horizon and has the potential to change the landscape of tissue: magnetically actuated extracellular matrices, or MagMA.

MagMA to revolutionize tissue engineering

As described in a pioneering article published in the “Device” journal by Rios and colleagues, they envisioned a substrate capable of dynamically applying mechanical forces to cells, precisely guiding their alignment and behavior. This substrate has the property of influencing cell anisotropy, meaning the properties that organized cells in tissues exhibit concerning the direction of the stimulus.

To grasp the concept of anisotropy, it is possible to consider a tree trunk seen in cross-section, with its succession of growth rings. As intuitive, the mechanical responses to twisting and pressure will differ if applied transversely or longitudinally concerning the trunk’s rings. The same principle applies to muscles, which exhibit different structural and functional properties and behaviors based on how constituent cells are organized in the tissue and how mechanical stimulus is applied concerning force, direction, and temporal variability.

According to the authors, MagMA — a magnetically actuated platform poised to revolutionize the field of tissue engineering — can influence cell behavior and enable the programming of morphological and functional anisotropy within tissues, particularly in skeletal muscles.

One of the potential applications of MagMA involves dynamically programming the alignment of muscle fibers. In the context of skeletal muscle tissue engineering, the ability to control the directionality of muscle fiber alignment is crucial for a wide range of applications, from regenerative medicine to biohybrid robotics. By employing dynamically guided mechanical stimulation using MagMA, researchers can achieve coordinated alignment and contractility of muscle tissues.

MagMA will offer higher value and flexibility in future solutions

Previous muscle engineering techniques had significant limitations in achieving such coordination properties. Programming cell properties and functions could only occur at the time of implantation and remained unchanged later, without any corrective intervention if the tissue’s operating conditions changed—that is typically occurring in human tissues. In contrast, MagMA allows real-time adjustment of stimulation parameters, enabling researchers to modify patterns of muscle cell alignment even after implantation. This potential capability could offer higher value and flexibility in future solutions.

A significant advantage of MagMA is its capacity to separate the mechanical and biochemical effects of muscular exercises. Several studies demonstrated that exercise could lead to significant increases in muscle strength and alterations in fiber characteristics. To achieve this, rehabilitative practices used passive mechanical stimulation techniques to facilitate the recovery of patients’ muscular functionality.

However, research by Rios and colleagues revealed that mechanical stimulation alone is not equivalent to exercise, suggesting that synergistic effects may result from the combination of biochemical and mechanical stimulation. This discovery opens the door to exploring MagMA’s effects in combination with other forms of stimulation, further expanding the possibilities of tissue engineering.

The development of MagMA marks a true revolution in tissue engineering. With the introduction of dynamic mechanical stimulation, this platform enables real-time control of cell alignment and behavior within artificially created tissues. The robustness and adaptability of the technology make it applicable to a wide range of cell types and chemical characteristics of hydrogels, further expanding its utility.

While acknowledging the need for deeper studies and continued development of operational models closer to real tissues, the MagMA platform is potentially a true game-changer in the field of tissue engineering. Its ability to program anisotropy in artificially created tissues, such as skeletal muscles, opens a realm of possibilities for regenerative medicine and biohybrid robotics.

As researchers continue to explore its developmental potential and refine applications, making them more robust and flexible, it is possible to anticipate a new era in tissue engineering that combines the precision of mechanical control with the complexity of biological systems.