Astrocytes, the unexpected conductors of brain networks

 

Dozens of synapses from distinct neural circuits gather around a specialised astrocyte structure called a leaflet, which is capable of detecting and integrating the activities of multiple synapses.
Image Credit: © Lucas BENOIT et Rémi GRECO/ GIN

A collaborative study between the Universities of Lausanne (UNIL) and Geneva (UNIGE), the Grenoble Institute of Neuroscience (GIN) and the Wyss Centre for Bio and Neuroengineering reveals a previously unknown role for astrocytes in the brain's processing of information. Published in the journal Cell, their study shows that these glial cells are capable of integrating and processing signals from several neurons at once. Using cutting-edge imaging techniques, the team identified new specialised structures called leaflets, which enable astrocytes to connect several neurons, and thus neural networks. This represents a conceptual shift in our understanding of the brain.

The brain does not function via neurons alone. In fact, nearly half of the cells that make up the brain are glial cells, and among them, astrocytes occupy a special place. Their name comes from their star-shaped skeleton, but their external appearance is more reminiscent of certain nebular stars, with an irregular, filamentary contour that allows them to insert themselves into the smallest gaps between neurons, blood vessels, and other cells. They are thus in close contact with synapses, the communication hubs between neurons.

Early changes during brain development may hold the key to autism and schizophrenia

Photo Credit: Michal Jarmoluk

Researchers at the University of Exeter have created a detailed temporal map of chemical changes to DNA through development and aging of the human brain, offering new insights into how conditions such as autism and schizophrenia may arise.

The team studied epigenetic changes – chemical tags on our DNA that control how genes are switched on or off. These changes are crucial in regulating the expression of genes, guiding brain cells to develop and specialize correctly.

One important mechanism, called DNA methylation, was examined in nearly 1,000 donated human brains, spanning life from just six weeks after conception through to 108 years of age. The researchers focused on the cortex, a region of the brain involved in high-level functions such as thought, memory, perception, and behavior. Correct development of the cortex during early life is important to support healthy brain function after birth.

Key driver of pancreatic cancer spread identified

A 3D tumor vessel-on-a-chip model, showing pancreatic cancer cells (green) invading an engineered blood vessel (red) by breaking down the vascular basement membrane (yellow).
Image Credit: Courtesy of Lee Lab

A Cornell-led study has revealed how a deadly form of pancreatic cancer enters the bloodstream, solving a long-standing mystery of how the disease spreads and identifying a promising target for therapy.

Pancreatic ductal adenocarcinoma is among the most lethal cancers, with fewer than 10% of patients surviving five years after diagnosis. Its microenvironment is a dense, fibrotic tissue that acts like armor around the tumor. This barrier makes drug delivery difficult and should, in theory, prevent the tumor from spreading. Yet the cancer metastasizes with striking efficiency – a paradox that has puzzled scientists.

New research published in the journal Molecular Cancer reveals that a biological receptor called ALK7 is responsible, by activating two interconnected pathways that work in tandem. One makes cancer cells more mobile through a process called epithelial-mesenchymal transition, and the other produces enzymes that physically break down the blood vessel walls.

NASA's IMAP Mission Successfully Launches to Study Our Solar System's Protective Bubble

Photo Credit: NASA / Kim Shiflett

A new era of space exploration began this morning with the successful launch of NASA's Interstellar Mapping and Acceleration Probe (IMAP) mission. The spacecraft, launched aboard a SpaceX Falcon 9 rocket from Kennedy Space Center, is on a journey to help us better understand the protective bubble surrounding our solar system, known as the heliosphere, and to improve our ability to predict space weather.

The IMAP mission is a collaborative effort led by Princeton University professor David J. McComas, with the Johns Hopkins Applied Physics Laboratory (APL) having built the spacecraft and now managing the mission operations. The spacecraft is equipped with a suite of 10 advanced instruments that will work together to sample, analyze, and map the particles streaming toward Earth from the edges of our solar system and beyond. This will provide invaluable new insights into the solar wind – the constant stream of particles from the sun – and the interstellar medium.

Visualisation of blood flow sharpens artificial heart

To be able to observe the blood flow in the artificial heart in real time, the researchers had to build a full-scale model of the human circulatory system.
Photo Credit:Emma Busk Winquist

Using magnetic cameras, researchers at Linköping University have examined blood flow in an artificial heart in real time. The results make it possible to design the heart in a way to reduce the risk of blood clots and red blood cells breakdown, a common problem in today’s artificial hearts. The study, published in Scientific Reports, was done in collaboration with the company Scandinavian Real Heart AB, which is developing an artificial heart.

“The heart is a muscle that never rests. It can never rest. The heart can beat for a hundred years without being serviced or stopping even once. But constructing a pump that can function in the same way – that’s a challenge,” says Tino Ebbers, professor of physiology at Linköping University.

Nearly 9,000 heart transplants are performed worldwide per year, and the number keeps increasing. So does the number of people queuing for a new heart, with some 2,800 on the waiting list in the EU alone, and around 3,400 in the US.

Most of the patients whose heart does not work at all are currently connected to a machine that takes care of their blood circulation for them. It is a large device, and the patient is confined to their hospital bed. For those patients, an artificial heart could be an option while waiting for a donor heart.

UCLA researchers find “protective switches” that may make damaged livers suitable for transplantation

 

Photo Credit: Sasin Tipchai

In a mouse model of liver transplantation, UCLA researchers have identified proteins that act as “protective switches” guarding the liver against damage occurring when blood supply is restored during transplantation, a process known as ischemia-reperfusion injury.

The finding could increase the supply of donor organs by using molecular therapies to strengthen the liver’s protective pathways. By boosting this protection,  organs that would otherwise be discarded as damaged or suboptimal could be made suitable for transplantation and added to the donor pool, said Kenneth J. Dery, Ph.D , an associate adjunct professor of surgery in the division of liver and pancreas transplantation at the David Geffen School of Medicine at UCLA and the study’s co-senior author.

“One of the most intractable problems in the field of organ transplantation remains the nationwide shortage of donor livers, which has led to high patient mortality while waiting for a liver transplant,” Dery said. “This could ultimately help address the national transplant shortage and lower mortality rates.”

Supercritical subsurface fluids open a window into the world

Interpreted 3D seismic characteristics.
The seal layer, interpreted by looking at data on the supercritical fluid’s movement, appears as a distinct region. It’s disrupted where it meets a fault which makes it appear porous to the fluid, allowing it to migrate upwards, causing seismic vibrations.
Image Credit: ©2025 Tsuji et al.
(CC BY 4.0)

Researchers including those from the University of Tokyo build on past studies and introduce new methods to explore the nature and role of subsurface fluids including water in the instances and behaviors of earthquakes and volcanoes. Their study suggests that water, even heavy rainfall, can play a role in or even trigger seismic events. This could potentially lead to better early warning systems. The study improves models of seismic activity and can even help identify optimal sites for drilling to tap sources of supercritical geothermal energy.

As far as is currently known, earthquakes and volcanic eruptions cannot be predicted, certainly not on the timescales with which we expect from typical weather reports. But as physical theories improve, so does the accuracy of statistical models which could be useful for planning, and potentially also early warning systems, which can save lives when disaster does strike. Another benefit of improving such models is that they could help locate areas suitable for tapping into geothermal energy. So, it’s the improvement of theories, based on good observations, that geologists and other researchers strive for. And a recent development in this field has added another factor into the mix which may be more significant than was previously thought.

Grassland Butterflies – Important Indicators of the State of Nature

Small Copper (Lycaena phlaeas), a species for which the index shows a positive trend.
Photo Credit: Werner Messerschmid

With the Grassland Butterfly Index for Germany, UFZ scientists are providing important input for the implementation of the EU Nature Restoration Regulation.

One of the goals of the EU Nature Restoration Regulation, which came into force in 2024, is to halt species loss and preserve important ecosystem services provided by agricultural landscapes. Scientists at the Helmholtz Centre for Environmental Research (UFZ), in collaboration with the Senckenberg German Entomological Institute (SDEI), have now calculated the Grassland Butterfly Index for Germany – an indicator of the state of biodiversity proposed in the EU regulation. The results, published in the journal Nature Conservation, show a negative trend, especially in recent years. For their calculations, the researchers were able to draw on 4 million observation data collected at the UFZ over the last 20 years as part of the ‘Butterfly Monitoring Germany’ program.

How mosquito-borne viruses breach the brain’s defenses

Stem cell-derived blood-brain barrier cells.
Image Credit: Pablo Alvarez/Li Lab 

Mosquito-borne viruses can cause more than fevers and joint pain. In severe cases, they invade the brain, leading to seizures, encephalitis, lasting memory loss and sometimes death. But thanks to a new UCLA study, researchers have uncovered how some of these viruses breach the brain’s defenses — and point toward ways of keeping them out.

The research, published in Cell Reports, focuses on Sindbis virus, a relatively mild pathogen that scientists use as a safe stand-in for more dangerous mosquito-borne viruses such as chikungunya. 

Using a stem cell-based model of the human blood-brain barrier, developed with collaborators from Florida State University, the UCLA team compared two closely related Sindbis strains — one brain-invading and one not — and found that small changes in viral surface proteins called glycoproteins dictate whether the virus can cross.

The team discovered that the invasive strain grips just one or two specific proteins on blood-brain barrier cells, turning those proteins into doorways that let the virus inside. By contrast, the non-invasive strain spreads its efforts across many receptors and is far less successful.

Innovative transistors for quantum chips

Walter Weber, Masiar Sistani and Andreas Fuchsberger
Photo Credit: Technische Universität Wien

The smaller electronic components become, the more complex their manufacture becomes. This has been a major problem for the chip industry for years. At TU Wien, researchers have now succeeded for the first time in manufacturing a silicon-germanium (SiGe) transistor using an alternative approach that will not only enable smaller dimensions in the future, but will also be faster, require less energy and function at extremely low temperatures, which is important for quantum chips.

The key trick lies in the oxide layer that insulates the semiconductor: it is doped and produces a long-range effect that extends into the semiconductor. The technology was developed by TU Wien (Vienna), JKU Linz and Bergakademie Freiberg.