You’ve probably learned the hard way about how the grocery list can go out the window when you go shopping on an empty stomach. Part of the reason is that our sense of smell intensifies when we’re hungry, making the aroma of freshly baked cookies, fried chicken, and other tempting goodies even more noticeable. And this beautiful micrograph helps to provide a biological explanation for this phenomenon.
The image, which looks like something that Van Gogh might have painted, shows a thick mesh of neurons in a small cross section of a mouse’s olfactory bulb, a structure located in the forebrain of all vertebrates (including humans!) that processes input about odors detected by the nose. Here, you see specialized neurons called mitral cells (red) that can receive signals from the hypothalamus, a brain region known for its role in hunger and energy balance. Also fluorescently labeled are receptors that detect acetylcholine signals from the brain (green) and the nuclei of all cells in the olfactory bulb (blue).
Tags: brain, chemosensory pathways, confocal microscope, forebrain, hunger, hypothalmus, mitral cells, mouse, neurons, nose, odor, olfactory bulb, olfactory system, smell, University of Florida’s 2016 Elegance of Science
Writers have The Elements of Style, chemists have the periodic table, and biomedical researchers could soon have a comprehensive reference on how to make neurons in a dish. Kristin Baldwin of the Scripps Research Institute, La Jolla, CA, has received a 2016 NIH Director’s Pioneer Award to begin drafting an online resource that will provide other researchers the information they need to reprogram mature human skin cells reproducibly into a variety of neurons that closely resemble those found in the brain and nervous system.
These lab-grown neurons could be used to improve our understanding of basic human biology and to develop better models for studying Alzheimer’s disease, autism, and a wide range of other neurological conditions. Such questions have been extremely difficult to explore in mice and other animal models because they have shorter lifespans and different brain structures than humans.
Tags: 2016 NIH Director’s Pioneer Award, addiction, aging, aging brain, Alzheimer’s disease, anxiety, autism, brain, brain cells, dopamine, fibroblasts, human neurons, iN cells, induced Pluripotent Stem cells, iPSCs, mental illness, neurobiology, neurology, neuronal subtypes, neurons, nicotinic receptors, serotonin, The Periodic Table, transcription factors, wellderly
Birds do it, bees do it, and even educated fleas do it. No, not fall in love, as the late Ella Fitzgerald so famously sang. Birds and insects can see polarized light—that is, light waves transmitted in a single directional plane—in ways that provides them with a far more colorful and detailed view of the world than is possible with the human eye.
Still, thanks to innovations in microscope technology, scientists have been able to tap into the power of polarized light vision to explore the inner workings of many complex biological systems, including the brain. In this image, researchers used a recently developed polarized light microscope to trace the spatial orientation of neurons in a thin section of the mouse midbrain. Neurons that stretch horizontally appear green, while those oriented at a 45-degree angle are pinkish-red and those at 225 degrees are purplish-blue. What’s amazing is that these colors don’t involve staining or tagging the cells with fluorescent markers: the colors are generated strictly from the light interacting with the physical orientation of each neuron.
Tags: Alzheimer’s disease, Biophysical Society’s 2017 Art of Science Image Contest, brain, brain imaging, cancer, imaging, interference, light, malaria, microscopy, midbrain, multicolor microscopy, neurology, neurons, neuroscience, optics, physics, polarized light, polarized light microscopy, polscope, polychromatic polscope, sickle cell disease
When someone suffers a fully severed spinal cord, it’s considered highly unlikely the injury will heal on its own. That’s because the spinal cord’s neural tissue is notorious for its inability to bridge large gaps and reconnect in ways that restore vital functions. But the image above is a hopeful sight that one day that could change.
Here, a mouse neural stem cell (blue and green) sits in a lab dish, atop a special gel containing a mat of synthetic nanofibers (purple). The cell is growing and sending out spindly appendages, called axons (green), in an attempt to re-establish connections with other nearby nerve cells.
Tags: axons, bioengineering, biomaterials, FASEB Bioart 2016, nanofiber gel, nanofibers, neural stem cell, neurons, regenerative medicine, Scanning electron microscope, spinal cord, spinal cord injuries, stem cell, tissue engineering, tissue regeneration, traumatic injury, wound healing