As the weather starts to warm up, let’s look at some of the most exciting developments in this week’s science review.
Plasma proteins may be used to predict patients at risk for dementia
A research team at Fudan University has discovered a new biomarker for predicting dementia, a chronic condition that affects 10% of U.S. adults aged 70 and older. Though dementia broadly causes memory loss and other changes that interfere with daily life, there are many different types, ranging from the well-known Alzheimer’s disease to the extremely rare Creutzfeldt-Jakob disease. Currently, there is no cure for dementia.
The study, published in Nature, involved the analysis of over 50,000 U.K. Biobank participants’ plasma protein levels. The researchers found that individuals with higher levels of glial fibrillary acidic protein (GFAP), an intermediate protein found in central nervous system cells called astrocytes, were 2.32 times more likely to develop dementia. Further, levels of GFAP and another predictive plasma protein, neurofilament light polypeptide, began to change at least 10 years before patients were diagnosed with dementia. These findings suggest that GFAP levels could be used in clinical settings to assess patients’ risks of developing dementia and flag those with high levels for early intervention.
3D printer creates neural tissue with functional connectivity
For researchers studying the brain, one of the most pressing challenges is making realistic brain-like structures and models to experiment on. In the past few years, scientists have studied neural networks using various techniques such as computer and animal models.
One common method uses stem cells to create brain-like blobs called organoids; however, each organoid has a different structure, making it extremely difficult to reproduce results. 3D-printed neural tissue, on the other hand, is an example of a model that can be easily duplicated. In a study published in Cell Stem Cell, researchers from the University of Wisconsin-Madison and their collaborators have discovered a way for these 3D-printed cells to connect to each other, a quality that was previously impossible to investigate.
By modifying printing techniques, the researchers created layered neural tissues in which neural progenitor cells (NPCs) formed synapses across layers, while still keeping their own structures. While there is still a lot more room to improve the technology, this is an immense step in understanding how different neurodegenerative diseases can change the connectivity within the brain.
Scientists discover a previous ocean inside Saturn’s moon, Mimas
Mimas — nicknamed the “Death Star” for its resemblance to the Empire's superweapon in Star Wars – is an unlikely place on which an ocean can be found. Usually celestial bodies with “long-lived global oceans” have markings that are visible on their surfaces. Mimas, however, has none.
From a detailed analysis of how the moon moves relative to the effects of Saturn’s gravitational pull, researchers and astronauts from the Paris Observatory concluded that there must have been a large ocean on Mimas’ surface. This ocean is also believed to have been relatively young, having appeared only between 2 and 25 million years ago and located 20 to 30 kilometers below the surface of the planet.
Molecule on the second X chromosome leads women to have more autoimmune diseases
Though male and female karyotypes appear identical apart from the 23rd pair of chromosomes, a study found that this sex chromosome difference may be the reason why women are more likely to have autoimmune diseases than men. Led by Howard Chang from Stanford University, a research team found that the Xist molecule that wraps around a female’s second X chromosome contains many of the proteins also present in autoimmune diseases.
While the Xist molecule essentially silences the second X chromosome, which could otherwise release an excess supply of potentially toxic proteins, Chang’s team investigated whether the molecule could also be causing autoimmune diseases. After genetically engineering a strain of male mice — which do not naturally suffer from extreme lupus — to include the Xist molecule, the researchers found that the levels of the autoimmune disease increased.
