Molecular Psychiatry<\/a>.<\/p>\nThe researchers had known from earlier experiments that microglial immune cells are important for the regulation of anxiety. But they had found that all microglia seemed to do the same thing. When they interfered with a specific group of microglia, called Hoxb8 microglia, mice started to act anxious. But when the researchers prevented the activity of all microglia at once\u2014including Hoxb8 and non-Hoxb8 microglia\u2014mice behaved normally.<\/p>\n
This led the researchers to suspect that the two groups of microglia do opposite things: Hoxb8 microglia prevent anxiety while non-Hoxb8 microglia promote it. But to learn for sure, they needed to see what each group of cells did on their own.<\/p>\n
The researchers\u2019 results hinged on an unconventional experiment: transplanting different kinds of microglia brain cells into mice that lack microglia altogether.<\/p>\n
The researchers found that non-Hoxb8 microglia act as a gas pedal for anxiety. When researchers transplanted non-Hoxb8 microglia into mice without any other microglia, the mice groomed themselves compulsively and spent less time in open spaces\u2014classic signs of higher anxiety. With only non-Hoxb8 microglia, the accelerator for anxiety was always on, with no brake pedal to keep it in check.<\/p>\n
The other kind of microglia, Hoxb8 microglia, acts as the brake pedal for anxiety. Mice transplanted with only Hoxb8 microglia weren\u2019t anxious. And, importantly, mice with both kinds of microglia\u2014the gas and the brake\u2014weren\u2019t anxious either. Non-Hoxb8 microglia might be driving the mice towards anxiety, but it was balanced out by the anxiety-preventing activity of Hoxb8 microglia, so the mice did not show anxiety behaviors.<\/p>\n
\u201cThese two populations of microglia have opposite roles,\u201d explains Mario Capecchi, distinguished professor of biology and of human genetics and the senior author on the study.<\/p>\n
\u201cTogether, they set just the right levels of anxiety in response to what is happening in the mouse\u2019s environment.\u201d<\/p>\n
The researchers say that their results could lay the foundations for major advances in how anxiety disorders are understood and ultimately treated.<\/p>\n
\u201cHumans also have two populations of microglia that function similarly,\u201d says Capecchi, a 2007 Nobel laureate. But existing medications for psychiatric conditions almost exclusively focus on neurons.<\/p>\n
By finding how other kinds of brain cells can drive anxiety, researchers could develop therapies that focus on these microglia\u2014activating the brakes or weakening the accelerator.<\/p>\n
\u201cThis knowledge will provide the means for patients who have lost their ability to control their levels of anxiety to regain it,\u201d Capecchi says.<\/p>\n
\u201cWe\u2019re far from the therapeutic side,\u201d Van Deren cautions, \u201cbut in the future, one could probably target very specific immune cell populations in the brain and correct them through pharmacological or immunotherapeutic approaches. This would be a major shift in how to treat neuropsychiatric disorders.\u201d<\/p>\n
Support for the work came from\u00a0the National Institutes of Health, specifically the National Institute of Mental Health, as well as the Dauten Family Foundation and the University of Utah Flow Cytometry Facility.<\/p>\n
Content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.<\/p>\n
Source: University of Utah<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Share this Article You are free to share this article under the Attribution 4.0 International license. Research in…\n","protected":false},"author":2,"featured_media":200509,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[77],"tags":[3083,31234,18,19,17,133],"class_list":{"0":"post-200508","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-anxiety","9":"tag-brains","10":"tag-eire","11":"tag-ie","12":"tag-ireland","13":"tag-science"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/115613899400719031","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/200508","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=200508"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/200508\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/200509"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=200508"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=200508"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=200508"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}