{"id":133279,"date":"2024-12-04T17:38:20","date_gmt":"2024-12-04T10:38:20","guid":{"rendered":"https:\/\/hotvideos24.online\/?p=133279"},"modified":"2024-12-04T17:38:20","modified_gmt":"2024-12-04T10:38:20","slug":"neurons-dont-look-like-weve-long-thought-controversial-study-says-sciencealert","status":"publish","type":"post","link":"https:\/\/hotvideos24.online\/?p=133279","title":{"rendered":"Neurons Don&#8217;t Look Like We&#8217;ve Long Thought, Controversial Study Says : ScienceAlert"},"content":{"rendered":"<p> <script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3711241968723425\"\r\n     crossorigin=\"anonymous\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-layout-key=\"-fb+5w+4e-db+86\"\r\n     data-ad-client=\"ca-pub-3711241968723425\"\r\n     data-ad-slot=\"7910942971\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><br \/>\n<\/p>\n<div>\n<p>The <a href=\"https:\/\/theconversation.com\/the-brain-is-the-most-complicated-object-in-the-universe-this-is-the-story-of-scientists-quest-to-decode-it-and-read-peoples-minds-222458\">most complicated object in the known Universe<\/a> is bound to inspire some heated debate, but neuroscientists are now arguing over a basic aspect of the brain we thought we&#8217;d figured out.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>A controversial study, led by Jacqueline Griswold from Johns Hopkins University in the US, has some scientists arguing for a fundamental change in how we view neurons \u2013  the building blocks of the brain and nervous system.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>Despite what most diagrams show, axons \u2013 the main arms of neurons \u2013 are not a smooth cylinder, they say, but more like a string of pearls. The size and spacing of those nanoscopic bumps are dynamic, possibly controlling how quickly messages are sent in the brain.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>&#8220;Understanding the structure of axons is important for understanding brain cell signaling,&#8221; <a href=\"https:\/\/www.hopkinsmedicine.org\/news\/newsroom\/news-releases\/2024\/12\/study-may-reverse-century-old-understanding-of-the-shape-of-arms-on-mammals-brain-cells\">explains<\/a> molecular neuroscientist Shigeki Watanabe, who is head of the lab at Johns Hopkins.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>&#8220;Axons are the cables that connect our brain tissue, enabling learning, memory, and other functions. These findings challenge a century of understanding about axon structure.&#8221;<\/p>\n<figure id=\"attachment_145766\" aria-describedby=\"caption-attachment-145766\" style=\"width: 642px\" class=\"wp-caption alignnone\"><img decoding=\"async\" src=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/GettyImages-1153647071-642x383.jpg\" alt=\"Neuron Anatomy\" width=\"642\" height=\"383\" class=\"wp-image-145766 size-medium\" srcset=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/GettyImages-1153647071-642x383.jpg 642w, https:\/\/www.sciencealert.com\/images\/2024\/12\/GettyImages-1153647071-696x415.jpg 696w, https:\/\/www.sciencealert.com\/images\/2024\/12\/GettyImages-1153647071-768x458.jpg 768w, https:\/\/www.sciencealert.com\/images\/2024\/12\/GettyImages-1153647071-1536x916.jpg 1536w, https:\/\/www.sciencealert.com\/images\/2024\/12\/GettyImages-1153647071-2048x1221.jpg 2048w, https:\/\/www.sciencealert.com\/images\/2024\/12\/GettyImages-1153647071-600x358.jpg 600w\" sizes=\"auto, (max-width: 642px) 100vw, 642px\" loading=\"lazy\"\/><figcaption id=\"caption-attachment-145766\" class=\"wp-caption-text\">Classic neuron anatomy (Vitalii Dumma\/Getty Images)<\/figcaption><\/figure>\n<p>It&#8217;s a tiny detail that could have big repercussions, but other neuroscientists aren&#8217;t buying it.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>&#8220;I think it&#8217;s true that [the axon is] not a perfect tube, but it&#8217;s not also just this kind of accordion that they show,&#8221; neuroscientist Christophe Leterrier from Aix-Marseille University <a href=\"https:\/\/www.science.org\/content\/article\/controversial-study-redraws-classical-picture-neuron\">told<\/a> Sofia Quaglia at Science.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p><a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/31427070\/\">Previous studies<\/a> have found that when brain cells are damaged or dying, the tails can start to &#8216;bubble&#8217;, creating a bead-like pattern. &#8216;Axonal beading&#8217; is especially common in the brains of those with  <a href=\"https:\/\/www.sciencealert.com\/go\/IaO\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73015\" data-postid=\"145765\" rel=\"nofollow noopener\" target=\"_self\">Alzheimer&#8217;s<\/a> or  <a href=\"https:\/\/www.sciencealert.com\/go\/IYl\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73029\" data-postid=\"145765\" rel=\"nofollow noopener\" target=\"_self\">Parkinson&#8217;s<\/a> disease.<\/p>\n<figure id=\"attachment_145772\" aria-describedby=\"caption-attachment-145772\" style=\"width: 642px\" class=\"wp-caption alignnone\"><img decoding=\"async\" src=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/MouseTissueCulture-642x620.png\" alt=\"Mouse Tissue Culture\" width=\"642\" height=\"620\" class=\"wp-image-145772 size-medium\" style=\"letter-spacing: -0.025em;\" srcset=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/MouseTissueCulture-642x620.png 642w, https:\/\/www.sciencealert.com\/images\/2024\/12\/MouseTissueCulture-430x415.png 430w, https:\/\/www.sciencealert.com\/images\/2024\/12\/MouseTissueCulture-768x742.png 768w, https:\/\/www.sciencealert.com\/images\/2024\/12\/MouseTissueCulture-600x580.png 600w, https:\/\/www.sciencealert.com\/images\/2024\/12\/MouseTissueCulture.png 820w\" sizes=\"auto, (max-width: 642px) 100vw, 642px\" loading=\"lazy\"\/><figcaption id=\"caption-attachment-145772\" class=\"wp-caption-text\">The axons of mouse neurons via three different imaging and culturing techniques. (Griswold et al., <em>Nature Neuroscience<\/em>, 2024)<\/figcaption><\/figure>\n<p>But Watanabe and his colleagues say the pearls they have found in the brains of mice are on a nanoscale, not a microscale like previous cases of axonal beading.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>Analyzing the brain slices of mice at various ages, the team has zoomed in on individual axons without a protective sheath.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>No matter how the brain tissue slices were cultured, axons did not look smooth but were riddled with &#8216;nanopearls&#8217; of various sizes.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>What&#8217;s more, the size of these pearls could be manipulated with predictive outcomes. Removing cholesterol from the axon, for instance, resulted in less pearling and a reduced ability to send electrical messages.<\/p>\n<figure id=\"attachment_145770\" aria-describedby=\"caption-attachment-145770\" style=\"width: 642px\" class=\"wp-caption alignnone\"><img decoding=\"async\" src=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/CholesterolRemoval-642x444.png\" alt=\"Cholesterol Removal Neurons\" width=\"642\" height=\"444\" class=\"size-medium wp-image-145770\" srcset=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/CholesterolRemoval-642x444.png 642w, https:\/\/www.sciencealert.com\/images\/2024\/12\/CholesterolRemoval-600x415.png 600w, https:\/\/www.sciencealert.com\/images\/2024\/12\/CholesterolRemoval-768x531.png 768w, https:\/\/www.sciencealert.com\/images\/2024\/12\/CholesterolRemoval.png 1238w\" sizes=\"auto, (max-width: 642px) 100vw, 642px\" loading=\"lazy\"\/><figcaption id=\"caption-attachment-145770\" class=\"wp-caption-text\">Axons of mouse neurons with cholesterol removed and with cholesterol present. (Griswold et al., <a href=\"https:\/\/www.nature.com\/articles\/s41593-024-01813-1\"><em>Nature Neuroscience<\/em><\/a>, 2024)<\/figcaption><\/figure>\n<p>But some critics think the nanopearls seen in mouse neurons are responses to the stress of tissue culturing.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>Previous studies have found that when <a href=\"https:\/\/royalsocietypublishing.org\/doi\/10.1098\/rsif.2020.0331#d1e2045\">stretched<\/a>, axons can form macro beads that are sort of like &#8220;<a href=\"https:\/\/rupress.org\/jcb\/article\/223\/8\/e202407024\/276848\/Stress-balls-for-the-brain-How-beading-protects\">stress balls for the brain<\/a>&#8220;. These clumps might form to stop the spread of damaging wave signals through a neuron&#8217;s tail, and they tend to somewhat resolve after about 15 minutes.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>If culture techniques stress a mammalian neuron, then some experts believe it is possible nanopearls will form. But if that occurs, this would be a response to stress, not a healthy state.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>Lead author Griswold <a href=\"https:\/\/www.science.org\/doi\/full\/10.1126\/science.1232251\">told<\/a> Science that is why her team also imaged live cells that were not frozen or chemically affixed. These, too, showed the nanopearl pattern.<\/p>\n<figure id=\"attachment_145773\" aria-describedby=\"caption-attachment-145773\" style=\"width: 642px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/LiveNeuronNanopearls-642x207.png\" alt=\"Live Nanopearls\" width=\"642\" height=\"207\" class=\"size-medium wp-image-145773\" srcset=\"https:\/\/www.sciencealert.com\/images\/2024\/12\/LiveNeuronNanopearls-642x207.png 642w, https:\/\/www.sciencealert.com\/images\/2024\/12\/LiveNeuronNanopearls-1024x331.png 1024w, https:\/\/www.sciencealert.com\/images\/2024\/12\/LiveNeuronNanopearls-768x248.png 768w, https:\/\/www.sciencealert.com\/images\/2024\/12\/LiveNeuronNanopearls-1536x496.png 1536w, https:\/\/www.sciencealert.com\/images\/2024\/12\/LiveNeuronNanopearls-2048x662.png 2048w, https:\/\/www.sciencealert.com\/images\/2024\/12\/LiveNeuronNanopearls-600x194.png 600w\" sizes=\"auto, (max-width: 642px) 100vw, 642px\"\/><figcaption id=\"caption-attachment-145773\" class=\"wp-caption-text\">STED micrographs showing pearled axon morphology in live neurons from organotypic slice cultures. Individual axons are straightened and represented on the right panels.  (Griswold et al., <a href=\"https:\/\/www.nature.com\/articles\/s41593-024-01813-1\"><em>Nature Neuroscience<\/em><\/a>, 2024)<\/figcaption><\/figure>\n<p>In Griswold&#8217;s experiments, the chemical that is usually used for imaging neurons caused the nanopearls to disappear, possibly explaining why they haven&#8217;t been seen before.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>That said, some scientists <em>have<\/em> seen similar nanopearling in the axons of <a href=\"https:\/\/www.science.org\/doi\/10.1126\/science.ade5645\">comb jellies<\/a>, and in the past, Watanabe has regularly noticed the effect in <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s12021-012-9149-y\">roundworm<\/a> axons, too.<\/p>\n<p><!-- START single\/mrec --><br \/>\n<!-- END single\/mrec --><\/p>\n<p>More evidence is the only way to end the debate once and for all. Watanabe and his colleagues at Johns Hopkins are now studying the neurons from human brains to see if they can find more nanopearls in a unit a hundred times smaller than the width of a hair.<\/p>\n<p>The study was published in <i><a href=\"https:\/\/www.nature.com\/articles\/s41593-024-01813-1\">Nature Neuroscience<\/a>.<\/i><\/p>\n<\/p><\/div>\n<p><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3711241968723425\"\r\n     crossorigin=\"anonymous\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-layout-key=\"-fb+5w+4e-db+86\"\r\n     data-ad-client=\"ca-pub-3711241968723425\"\r\n     data-ad-slot=\"7910942971\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><br \/>\n<br \/><div data-type=\"_mgwidget\" data-widget-id=\"1660802\">\r\n<\/div>\r\n<script>(function(w,q){w[q]=w[q]||[];w[q].push([\"_mgc.load\"])})(window,\"_mgq\");\r\n<\/script>\r\n<br \/>\n<br \/><a href=\"https:\/\/www.sciencealert.com\/neurons-dont-look-like-weve-long-thought-controversial-study-says\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The most complicated object in the known Universe is bound to inspire some heated debate, but neuroscientists are now arguing over a basic aspect of the brain we thought we&#8217;d &hellip; <a href=\"https:\/\/hotvideos24.online\/?p=133279\" class=\"more-link\">Read More<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8628],"tags":[],"class_list":["post-133279","post","type-post","status-publish","format-standard","hentry","category-science","entry"],"_links":{"self":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts\/133279","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=133279"}],"version-history":[{"count":0,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts\/133279\/revisions"}],"wp:attachment":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=133279"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=133279"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=133279"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}