In a recent paper published in the International Journal of Psychiatry Research, Dr. Gerard Marx from MX Biotech and Prof. Chaim Gilon from the Hebrew University of Jerusalem present an innovative integration of two notable neuroscience theories—the Global Neuronal Network (GNW) hypothesis and the Tripartite Mechanism of Memory.
A collaborative effort between Harvard and Google has led to a breakthrough in brain science, producing an extensive 3D map of a tiny segment of human brain, revealing complex neural interactions and laying the groundwork for mapping an entire mouse brain.
A cubic millimeter of brain tissue may not sound like much. But considering that tiny square contains 57,000 cells, 230 millimeters of blood vessels, and 150 million synapses, all amounting to 1,400 terabytes of data, Harvard and Google researchers have just accomplished something enormous.
A Harvard team led by Jeff Lichtman, the Jeremy R. Knowles Professor of Molecular and Cellular Biology and newly appointed dean of science, has co-created with Google researchers the largest synaptic-resolution, 3D reconstruction of a piece of human brain to date, showing in vivid detail each cell and its web of neural connections in a piece of human temporal cortex about half the size of a rice grain.
Engineers at MIT have developed a groundbreaking method for detecting bioluminescent light within the brain.
By modifying the brain’s blood vessels to express a specific protein, they induced dilation in response to light exposure.
The approach enabled researchers to visualize the dilation using magnetic resonance imaging (MRI), facilitating precise localization of light sources within the brain.
A new study has attempted to uncover the mysteries of the brain’s signal conversion process and the findings are interesting.
The brain’s ability to rid itself of toxins may actually be reduced during sleep, contrary to the leading scientific theory.
Over the past decade, the leading explanation for why we sleep has been that it provides the brain with an opportunity to flush out toxins.
However, a new study led by scientists at the UK Dementia Research Institute (UK DRI) at Imperial College London indicates that this may not be true.
Researchers have made a digital map showing a tiny chunk of a human brain in unprecedented detail.
Based on a brain tissue sample that had been surgically removed from a person, the map represents a cubic millimeter of brain—an area about half the size of a grain of rice. But even that tiny segment is overflowing with 1.4 million gigabytes of information—containing about 57,000 cells, 230 millimeters of blood vessels and 150 million synapses, the connections between neurons.
The researchers published their findings in the journal Science on Friday. They have made the data set freely available online and provided tools for analyzing and proofreading it.
Presynapses locally recycle synaptic vesicles to efficiently communicate information. During use and recycling, proteins on the surface of synaptic vesicles break down and become less efficient. In order to maintain efficient presynaptic function and accommodate protein breakdown, new proteins are regularly produced in the soma and trafficked to presynaptic locations where they replace older protein-carrying vesicles. Maintaining a balance of new proteins and older proteins is thus essential for presynaptic maintenance and plasticity. While protein production and turnover have been extensively studied, it is still unclear how older synaptic vesicles are trafficked back to the soma for recycling in order to maintain balance. In the present study, we use a combination of fluorescence microscopy, hippocampal cell cultures, and computational analyses to determine the mechanisms that mediate older synaptic vesicle trafficking back to the soma. We show that synaptic vesicles, which have recently undergone exocytosis, can differentially utilize either the microtubule or the actin cytoskeleton networks. We show that axonally trafficked vesicles traveling with higher speeds utilize the microtubule network and are less likely to be captured by presynapses, while slower vesicles utilize the actin network and are more likely to be captured by presynapses. We also show that retrograde-driven vesicles are less likely to be captured by a neighboring presynapse than anterograde-driven vesicles. We show that the loss of synaptic vesicle with bound molecular motor myosin V is the mechanism that differentiates whether vesicles will utilize the microtubule or actin networks. Finally, we present a theoretical framework of how our experimentally observed retrograde vesicle trafficking bias maintains the balance with previously observed rates of new vesicle trafficking from the soma.
Cytoskeleton-based trafficking mechanics have long been explored because of their essential role in neuronal function and maintenance (Westrum et al., 1983; Okada et al., 1995; Sorra et al., 2006; Perlson and Holzbaur, 2007; Tao-Cheng, 2007; Hirokawa et al., 2009; Staras and Branco, 2010; Tang et al., 2013; Wu et al., 2013; Maeder et al., 2014; Guedes-Dias et al., 2019; Gramlich et al., 2021; Watson et al., 2023). Protein trafficking via cytoskeleton transport is essential for synaptogenesis (Perlson and Holzbaur, 2007; Santos et al., 2009; Klassen et al., 2010; Wu et al., 2013; Guedes-Dias et al., 2019; Guedes-Dias and Holzbaur, 2019; Kurshan and Shen, 2019; Watson et al., 2023) and to replace older proteins with newer proteins for efficient function (Cohen et al., 2013; Dörrbaum et al., 2018, 2020; Heo et al., 2018; Truckenbrodt et al., 2018; Jähne et al., 2021; Watson et al., 2023).
In a discovery that could hasten treatment for patients with multiple sclerosis (MS), UC San Francisco scientists have discovered a harbinger in the blood of some people who later went on to develop the disease.
In about 1 in 10 cases of MS, the body begins producing a distinctive set of antibodies against its own proteins years before symptoms emerge. These autoantibodies appear to bind to both human cells and common pathogens, possibly explaining the immune attacks on the brain and spinal cord that are the hallmark of MS.
The findings were published in Nature Medicine on April 19.