Biotechnologists at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have developed a system to accurately measure muscle weakness caused by structural changes in muscle tissue. The new method allows muscle function to be assessed using imaging without the need for sophisticated biomechanical recordings, and could in future even make taking tissue samples for diagnosing myopathy superfluous.
The muscle is a highly ordered and hierarchically structured organ. This is reflected not only in the parallel bundling of muscle fibres, but also in the structure of individual cells.
The myofibrils responsible for contraction consist of hundreds of identically structured units connected one after another. This orderly structure determines the force which is exerted and the strength of the muscle.
Inflammatory or degenerative diseases or cancer can lead to a chronic restructuring of this architecture, causing scarring, stiffening or branching of muscle fibres and resulting in a dramatic reduction in muscular function.
Although such changes in muscular morphology can already be tracked using non-invasive multiphoton microscopy, it has not yet been possible to assess muscle strength accurately on the basis of imaging alone.
New system correlates structure and strength
Researchers from the Chair of Medical Biotechnology have now developed a system that allows muscular weakness caused by structural changes to be measured at the same time as optically assessing muscular architecture.
‘We engineered a miniaturized biomechatronics system and integrated it into a multiphoton microscope, allowing us to directly assess the strength and elasticity of individual muscle fibres at the same time as recording structural anomalies,’ explains Prof. Dr. Oliver Friedrich. In order to prove the muscle’s ability to contract, the researchers dipped the muscle cells into solutions with increasing concentrations of free calcium ions.
Calcium is also responsible for triggering muscle contractions in humans and animals. The viscoelasticity of the fibres was also measured, by stretching them little by little. A highly-sensitive detector recorded mechanical resistance exercised by the muscle fibres clamped on the device.
Data pool for simplified diagnosis
The technology developed by researchers at FAU is, however, merely the first step towards being able to diagnose muscle disorders much more easily in future: ‘Being able to measure isometric strength and passive viscoelasticity at the same time as visually showing the morphometry of muscle cells has enabled us, for the first time, to obtain direct structure-function data pairs’, Oliver Friedrich says.
‘This allows us to establish significant linear correlations between the structure and function of muscles at the single fibre level.’ The datapool will be used in future to reliably predict forces and biomechanical performances in skeletal muscle exclusively using optical assessments based on SHG images (the initials stand for Second Harmonic Generation and refer to images created using lasers at second harmonic frequency), without the need for complex strength measurements.
At present, muscle cells still have to be removed from the body before they can be examined using a multiphoton microscope. However, it is plausible that this may become superfluous in future if the necessary technology can continue to be miniaturized, making it possible for muscle function to be examined, for example, using a micro-endoscope.
Prof. Dr. Dr. Oliver Friedrich
Phone: +49 9131 85 23174
The results have been published in the renowned journal Light: Science & Application:
‘Optical prediction of single muscle fiber force production using a combined biomechatronics and second harmonic generation imaging approach’
Dr. Susanne Langer | idw - Informationsdienst Wissenschaft
Polymers get caught up in love-hate chemistry of oil and water
28.02.2020 | DOE/Oak Ridge National Laboratory
How do zebrafish get their stripes? New data analysis tool could provide an answer
28.02.2020 | Brown University
Researchers at the University of Bayreuth have discovered an unusual material: When cooled down to two degrees Celsius, its crystal structure and electronic properties change abruptly and significantly. In this new state, the distances between iron atoms can be tailored with the help of light beams. This opens up intriguing possibilities for application in the field of information technology. The scientists have presented their discovery in the journal "Angewandte Chemie - International Edition". The new findings are the result of close cooperation with partnering facilities in Augsburg, Dresden, Hamburg, and Moscow.
The material is an unusual form of iron oxide with the formula Fe₅O₆. The researchers produced it at a pressure of 15 gigapascals in a high-pressure laboratory...
Study by Mainz physicists indicates that the next generation of neutrino experiments may well find the answer to one of the most pressing issues in neutrino physics
Among the most exciting challenges in modern physics is the identification of the neutrino mass ordering. Physicists from the Cluster of Excellence PRISMA+ at...
Fraunhofer researchers are investigating the potential of microimplants to stimulate nerve cells and treat chronic conditions like asthma, diabetes, or Parkinson’s disease. Find out what makes this form of treatment so appealing and which challenges the researchers still have to master.
A study by the Robert Koch Institute has found that one in four women will suffer from weak bladders at some point in their lives. Treatments of this condition...
The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.
Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...
Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.
Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...
12.02.2020 | Event News
16.01.2020 | Event News
15.01.2020 | Event News
28.02.2020 | Materials Sciences
28.02.2020 | Life Sciences
28.02.2020 | Architecture and Construction