{"id":485142,"date":"2026-01-01T16:59:17","date_gmt":"2026-01-01T16:59:17","guid":{"rendered":"https:\/\/www.europesays.com\/us\/485142\/"},"modified":"2026-01-01T16:59:17","modified_gmt":"2026-01-01T16:59:17","slug":"scientists-link-gut-bacteria-to-bipolar-depression-in-mouse-study-sciencealert","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/485142\/","title":{"rendered":"Scientists Link Gut Bacteria to Bipolar Depression in Mouse Study : ScienceAlert"},"content":{"rendered":"

Precise changes in the connectivity between neurons caused by an imbalance of gut bacteria<\/a> may help explain depressive symptoms<\/a> in bipolar disorder, a new animal study suggests.<\/p>\n

Researchers from Zhejiang University in China used fecal transplants to transfer gut bacteria from people with bipolar disorder into mice. The volunteers had all been diagnosed as being in a depressive phase<\/a> of bipolar within the last 24 hours.<\/p>\n

Through a combination of brain imaging, genetic sequencing, and behavioral tests, the scientists determined that the mice began to exhibit signs of depression<\/a> \u2013 moving less and showing less interest in treats, for example.<\/p>\n

Related: Bipolar Disorder Linked to a Higher Risk of Early Death Than Smoking<\/a><\/strong><\/p>\n

What’s more, crucial measures of brain connectivity weakened. In the medial prefrontal cortex<\/a> (mPFC) part of the brain, where a lot of decision making and emotional regulation happens, there were fewer connections (synapses) between cells, and the brain’s reward center was effectively cut off.<\/p>\n

“Mice transplanted with fecal microbiota from bipolar disorder patients displayed bipolar disorder depression-like behavior, accompanied by changes in neural structure and synaptic connectivity in the mPFC,” the researchers write<\/a> in their published paper.<\/p>\n

Animals that received fecal transplants from healthy volunteers showed no such changes.<\/p>\n

To test the nature of the depression, the researchers used two different medications: fluoxetine<\/a>, which is commonly used to treat major depressive disorder, and lithium<\/a>, a first-line therapy used to stabilize moods in conditions such as bipolar disorder.<\/p>\n

No improvement in mood was seen following fluoxetine, yet treatment with lithium resulted in a significant change in behavior.<\/p>\n

This matches the treatment response seen in the depressive phases of bipolar disorder<\/a>, as opposed to depression more generally. It’s another sign that the gut bacteria switch had effectively brought bipolar depression along with it.<\/p>\n

“Lithium has been reported to regulate the dopamine system and dopamine neuron firing, which are critical for reward processing,” write<\/a> the researchers.<\/p>\n

A further analysis of the gut bacteria transplanted from people with bipolar disorder into mice revealed varieties associated with negative health impacts \u2013 including Klebsiella (already linked to mood disorders<\/a>) and Alistipes (linked to depression<\/a>).<\/p>\n

“While specific bacterial genera were identified, more evidence is still needed to determine the exact role of [bacteria] in the pathogenesis of bipolar disorder,” the researchers note<\/a>.<\/p>\n

\"Genetic,A wide variety of factors are thought to contribute to bipolar disorder, including the microbiota\u2013gut\u2013brain (MGB) axis. (Ortega et al., Mol. Psychiatry., 2023<\/a>)<\/p>\n

There are several known drivers of bipolar disorder<\/a>, ranging from genetic to lifestyle and environmental factors, so the researchers aren’t suggesting that gut bacteria on their own would trigger the condition.<\/p>\n

Gut bacteria could be a contributing factor<\/a>, layered on top of other components, that possibly makes someone more vulnerable to developing bipolar disorder or worsens their symptoms.<\/p>\n

Understanding more about how a particular condition develops and differs from related disorders is a good step towards finding possible treatments.<\/p>\n

Imbalances in gut bacteria<\/a> have been found in people with bipolar disorder, which opens the door to possibly restoring gut bug communities<\/a> as a way to alleviate symptoms<\/a>.<\/p>\n

\"Subscribe<\/a><\/p>\n

Scientists are also making steady progress<\/a> in identifying how bipolar disorder gets started, pinpointing differences in brain wiring<\/a> and brain cell activity<\/a> as possible avenues to explore.<\/p>\n

With the condition now affecting<\/a> around 1 in 50 people worldwide at some point in their lives, there’s the potential to improve the lives of millions who experience extreme mood swings<\/a>.<\/p>\n

“Due to its complex clinical manifestations, the misdiagnosis rate of bipolar disorder is extremely high,” write<\/a> the researchers.<\/p>\n

“Therefore, clarifying the pathogenesis of bipolar disorder is of particular importance for early diagnosis and intervention in individuals with bipolar disorder.”<\/p>\n

The research has been published in Molecular Psychiatry<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Precise changes in the connectivity between neurons caused by an imbalance of gut bacteria may help explain depressive…\n","protected":false},"author":3,"featured_media":485143,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[210,352,67,132,68],"class_list":{"0":"post-485142","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-health","9":"tag-msft-content","10":"tag-united-states","11":"tag-unitedstates","12":"tag-us"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/115820912483473435","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/485142","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=485142"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/485142\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/485143"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=485142"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=485142"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=485142"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}