Scientists at UCL have developed a new technique that uses microscopic
magnetic particles to remotely activate brain cells; researchers say the
discovery in rats could potentially lead to the development of a new class
of non-invasive therapies for neurological disorders.
Published in Advanced Science, the pioneering technique called
"magnetomechanical stimulation" or , allows touch sensitive brain glial
cells called astrocytes to be stimulated with a magnetic device outside the
body.
Microscopic magnetic particles, or micromagnets, are attached to astrocytes,
and used as miniature mechanical switches that can turn "on" the cells when
a strong magnet is placed near the head.
Co-author, Professor Alexander Gourine (UCL Centre for Cardiovascular and
Metabolic Neuroscience) said: "Astrocytes are star-shaped cells found
throughout the brain. They are strategically positioned between the brain
blood vessels and nerve cells. These cells provide neurons with essential
metabolic and structural support, modulate neuronal circuit activity and may
also function as versatile surveyors of brain milieu, tuned to sense
conditions of potential metabolic insufficiency.
"The ability to control brain astrocytes using a magnetic field gives the
researchers a new tool to study the function of these cells in health and
disease that may be important for future development of novel and effective
treatments for some common neurological disorders, such as epilepsy and
stroke."
Senior author, Professor Mark Lythgoe (UCL Centre for Advanced Biomedical
Imaging) said: "Because astrocytes are sensitive to touch, decorating them
with magnetic particles means you can give the cells a tiny prod from
outside the body using a magnet, and as such, control their function. This
ability to remotely control astrocytes provides a new tool for understanding
their function and may have the potential to treat brain disorders."
In developing MMS, scientists at UCL set out to create a more clinically
relevant brain cell control technique. This contrasts with other existing
research tools, such as optogenetics and chemogenetics, which require
foreign genes to be inserted into the brain cells, typically with the help
of a virus. This need for genetic modification has been a major obstacle to
the clinical translation of the existing methods.
Lead researcher Dr. Yichao Yu (UCL Centre for Advanced Biomedical Imaging)
said: "Our new technology uses magnetic particles and magnets to remotely
and precisely control brain cell activity and, importantly, does this
without introducing any device or foreign gene into the brain.
"In the laboratory-based study, we coated microscopic magnetic particles
with an antibody that enables them to bind specifically to astrocytes. The
particles were then delivered to the target brain region in the rat via
injection.
"Another advantage of using micromagnets is that they light up on an MRI
scan so we can track their location and target very particular parts of the
brain to get precise control of brain function."
Professor Lythgoe, who received the Royal Society of Medicine Ellison–Cliffe
Award 2021 for his "contribution of fundamental science to the advancement
of medicine", added: "We are very excited about this technology because of
its clinical potential. In contrast to existing methods, MMS takes advantage
of the remarkable sensitivity to touch of certain brain cells, therefore
neither genetic modification nor device implantation is needed. This makes
MMS a promising candidate as an alternative, less invasive therapy compared
to the currently used deep brain stimulation techniques that require the
insertion of electrodes into the brain."
Reference:
Yichao Yu et al, Remote and Selective Control of Astrocytes by
Magnetomechanical Stimulation, Advanced Science (2021).
DOI: 10.1002/advs.202104194
Tags:
Medical Science