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Han, M.-H.

Publications and source records attributed to Han, M.-H..

3 recordsLinked to original sources

CRF neurons of the BNST promote resilience by blunting the internal experience of aversion.

The Bed Nucleus of the Stria Terminalis (BNST) has been studied extensively for its coordination of opposing adaptive behaviors. Previously, we uncovered a critical role for Corticotropin-Releasing Factor (CRF)-expressing neurons of the oval nucleus of the BNST (BNSTovCRF) in maintaining resilience to social defeat through stress-dependent self-sustaining neuronal activity.1 However, as mice develop resilience, it is not well-understood how affect and motivation are altered to achieve adaptive behavior in the face of ongoing threat. Here, we explore how this neuronal population exerts a powerful influence over internal state in various stress contexts to promote adaptive social responding. Using cell-type-selective optogenetics, a suite of behavioral paradigms, and transgenic Crf-ChR2 mice, we show that BNSTovCRF neurons induce resiliency by altering the encoding of psychosocial stress, enhancing the appetitiveness of social interaction, and enhancing tolerability to physical stress. Adaptive responses to stress typically emanate as a response to negative internal states by external stimuli; here, we show that in resilient mice, stressful environments are less aversive than susceptible mice, suggesting a different motivational capacity to endure stress in this group. Thus, we describe a novel role for BNSTovCRF neurons in resisting the emotional effects of cumulative stress by reducing the internal experience of aversion

neuroscience↗

CRF Neurons Establish Resilience via Stress-History-Dependent BNST Modulation

IntroductionCumulative stress is a major risk factor for developing major depressive disorder (MDD), yet not everyone experiencing chronic stress develops MDD. In those who do not, it is unclear at what point, or by what mechanism, a trajectory of stable resiliency emerges. MethodsUtilizing a 10-day repeated social defeat stress model (RSDS) for MDD, we observed that a critical period between 7 and 10 daily defeats marks the phenotypical divergence of resilient from susceptible mice. Using cell-type selective electrophysiology, chemogenetics, optogenetics, fiber photometry and RNA quantification was employed to investigate the nature of stress effects on neuroadaptation in the oval nucleus of the bed nucleus of the stria terminalis (BNSTov) required to determine resilience. ResultsIn response to ongoing stress, corticotropin-releasing factor (CRF+, but not CRF-) neurons of the (BNSTov) displayed a sustained increased firing rate in resilient, but not susceptible mice. This neurophysiological adaptation was self-sustaining, but only after 7 critical stress exposures, indicating that the process of developing resilience is dependent on stress history. ConclusionOur study reveals a novel process by which individuals might persist in the face of adversity by way of stress-provoked activation, not inhibition of a key CRF limbic region that establishes a pathway to resilience.

neuroscience↗

Predictive factors for the development of peritumoral brain edema after LINAC-based radiation treatment in patients with intracranial meningioma

Background and purposeDisruption of the tumor-brain barrier in meningioma plays a critical role in the development of peritumoral brain edema (PTBE). We hypothesized that osteoporotic conditions may be associated with PTBE occurrence after radiation in patients with intracranial meningioma. MethodsWe measured Hounsfield units (HU) of the frontal skull on simulation brain CT in patients who underwent linear accelerator (LINAC)-based radiation treatment for intracranial meningioma. Receiver operating characteristic curve analysis was performed to determine the optimal cut-off values for several predictive factors. The cumulative hazard for PTBE was estimated and classified according to these factors. Hazard ratios were then estimated to identify independent predictive factors associated with the development of PTBE after radiation in intracranial meningioma patients. ResultsA total of 83 intracranial meningiomas in 76 patients who received LINAC-based radiation treatment in our hospital over an approximate 5-year period were included for the study. We found mean frontal skull HU [≤]630.625 and gross tumor volume >7.194 cc to be independent predictors of PTBE after radiation treatment in patients with meningioma (hazard ratio, 8.38; P=0.021; hazard ratio, 5.78; P=0.034, respectively). In addition, patients who were [≥]65 years showed a marginally significant association with PTBE. ConclusionsOur study suggests that possible osteoporotic conditions, large tumor volume, and older age may be associated with PTBE occurrence after LINAC-based radiation treatment for intracranial meningioma. In the future we anticipate that these findings may enhance the understanding of the underlying mechanisms of PTBE after radiation in meningioma patients.

neuroscience↗