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Woehr, M.

Publications and source records attributed to Woehr, M..

2 recordsLinked to original sources

Early life stress-induced miR-708-5p affects bipolar disorder-associated phenotypes through neuronatin downregulation

Mood-disorders (MDs) are caused by a complex interplay of genetic and environmental (GxE) risk factors. However, the molecular pathways engaged by GxE risk factors to trigger specific MD-associated endophenotypes are still poorly understood. Here, by using unbiased small RNA sequencing in peripheral blood mononuclear cells (PBMCs), we identified the BD-associated miR-708-5p as one of the most strongly upregulated microRNAs in peripheral blood of both healthy human subjects with a high genetic or environmental (early life stress) predisposition to develop MDs. miR-708 is also upregulated in the hippocampus of rats which underwent juvenile social isolation, a rodent model of early life stress. Furthermore, ectopic overexpression of miR-708-5p in the hippocampus of adult male mice is sufficient to elicit MD-associated behavioural endophenotypes, demonstrating a causal role for elevated miR-708-5p levels in MD development. We further show that miR-708-5p directly targets Neuronatin (Nnat), an endoplasmic reticulum (ER) resident protein involved in calcium homeostasis. Consequently, restoring Nnat expression in the hippocampus of miR-708-5p overexpressing mice rescues miR-708-5p dependent behavioural phenotypes. Finally, miR-708-5p is strongly upregulated in PBMCs derived from patients diagnosed with MD, in particular BD males. Peripheral expression of miR-708-5p, in conjunction with the previously identified miR-499-5p, allows to differentiate male BD patients from patients suffering from major depressive disorder (MDD) and healthy controls. In summary, we describe a functional role for the miR-708-5p/Nnat pathway in MD etiology and identify miR-708-5p as a potential biomarker for the differential diagnosis of MDs.

neuroscience↗

Bipolar-associated miR-499-5p controls neuroplasticity by downregulating the Cav1.2 L-type voltage gated calcium channel subunit CACNB2

Bipolar disorder (BD) is a chronic mood disorder characterized by alternating manic and depressive episodes, often in conjunction with cognitive deficits. Dysregulation of neuroplasticity and calcium homeostasis as a result of complex genetic environment interactions are frequently observed in BD patients, but the underlying molecular mechanisms are largely unknown. Here, we show that a BD-associated microRNA, miR-499-5p, regulates neuronal dendrite development and cognitive function by downregulating the BD risk gene CACNB2. miR-499-5p expression is increased in peripheral blood of BD patients and healthy subjects at risk of developing the disorder due to a history of childhood maltreatment. This up-regulation is paralleled in the hippocampus of rats which underwent juvenile social isolation. Elevating miR-499-5p levels in rat hippocampal pyramidal neurons impairs dendritogenesis and reduces surface expression and activity of the voltage-gated L-type calcium channel Cav1.2. We further identified CACNB2, which encodes a regulatory {beta}-subunit of Cav1.2, as a direct target of miR-499-5p in neurons. CACNB2 downregulation is required for the miR-499-5p dependent impairment of dendritogenesis, suggesting that CACNB2 is an important downstream target of miR-499-5p in the regulation of neuroplasticity. Finally, elevating miR-499-5p in the hippocampus in vivo is sufficient to induce short-term memory impairments in rats haploinsufficient for the Cav1.2 pore forming subunit Cacna1c. Taken together, we propose that stress-induced upregulation of miR-499-5p contributes to dendritic impairments and deregulated calcium homeostasis in BD, with specific implications for the neurocognitive dysfunction frequently observed in BD patients.

neuroscience↗