The bed nucleus of the stria terminalis (BNST) is known to play a critical role in mediating the behavioral and autonomic responses to stressors. The oval nucleus of the BNST (BNSTov) contains cell bodies that synthesize the stress hormone, corticotropin releasing factor (CRF). Although afferent fibers originating from the BNSTov have been shown to innervate several key structures of the neuroendocrine and central autonomic system, the question remains as to whether, some of these fibers are CRF-positive. To directly address this question, we injected a “floxed” anterograde tracer (rAAV5/EF1a-DIO-mCherry) into the BNSTov of CRFp3.0CreGFP transgenic mice, which express a green fluorescent protein (GFP) under the control of the CRF promoter. Serial sections were then analyzed for the presence of double-labeled fibers in potential projection sites. To determine whether CRF neurons in the rat BNSTov send comparable projections, we infused rat BNSTov with an AAV in which the human synapsin promoter drives enhanced GFP expression. We then used CRF immunoreactivity to examine double-labeled fluorescent fibers and axon terminals in projection sites from brain sections of the AAV-infused rats. We have observed several terminal fields in the mouse and rat brain with double-labeled fibers in the Dorsal raphe nucleus (DRD), the Paraventricular nucleus of the hypothalamus, and to a lesser extent in the Ventral tegmental area. We found double-labeled terminal boutons in the nucleus accumbens shell, prelimbic cortex, and posterior basolateral nucleus of the amygdala. The most intense double-labeling was found in midbrain, including substantia nigra pars compacta, red nucleus, periaqueductal gray, pontine nuclei, as well as DRD. The results of our study indicate that CRF neurons are the output neurons of the BNSTov and they send projections to the centers of neuroendocrine and autonomic regulation, but also regions modulating reward and motivation, vigilance, motor function, as well as affective behavior.

Rationale: NLRP3 activation and IL-1β production are implicated in Kawasaki Disease (KD) pathogenesis, however a detailed and complete characterization of the molecular networks and cellular subsets involved in the development of cardiovascular lesions is still lacking. Objective: Here, in a murine model of KD vasculitis, we used single-cell RNA sequencing and spatial transcriptomics to determine the cellular landscape of inflamed vascular tissues. Methods and Results: We observe infiltrations of innate and adaptive immune cells in murine KD cardiovascular lesions, associated with increased expression of Nlrp3 and Il1b. Monocytes, macrophages and dendritic cells were the main sources of IL-1β, whereas fibroblasts and vascular smooth muscle cells (VSMCs) expressed high levels of IL-1 receptor. VSMCs type 1 surrounding the inflamed coronary artery undergo a phenotype switch to become VSMCs type 2, which are characterized by gene expression changes associated with decreased contraction, and enhanced migration and proliferation. Genetic inhibition of IL-1β signaling on VSMCs efficiently attenuated the VSMCs type 2 phenotypic switch and the development of cardiovascular lesions during murine KD vasculitis. In addition, pharmacological inhibition of NLRP3 prevented the development of cardiovascular inflammation. Conclusions: Our studies unravel the cellular diversity involved in IL-1β production and signaling in murine KD cardiovascular lesions and provide the rationale for therapeutic strategies targeting NLRP3 to inhibit cardiovascular lesions associated with KD.

The inability to discriminate between threat and safety is a hallmark of stress-induced psychiatric disorders, including post-traumatic stress disorder. Dorsolateral bed nucleus of the stria terminalis (BNST dl ) is critically involved in the modulation of fear and anxiety, and has been proposed to regulate discrimination between signaled (cued, predictable) and unsignaled (unpredictable) threats. We recently showed that oxytocin receptors (OTRs) in the BNST dl facilitate acquisition of cued fear measured in a fear-potentiated startle (FPS). In the current study, using in vivo microdialysis in awake male Sprague–Dawley rats, a double immunofluorescence approach with confocal microscopy, as well as retrograde tracing of hypothalamic BNST-projecting OT neurons, we investigated whether fear conditioning activates OT system and modulates OT release. To determine the role of OTR in fear memory formation, we also infused OTR antagonist or OT into the BNST dl before fear conditioning and measured rats’ ability to discriminate between cued (signaled) and non-cued (unsignaled) fear using FPS. In contrast to acute stress (exposure to forced swim stress or foot shocks alone), cued fear conditioning increases OT content in BNST dl microdialysates. In addition, fear conditioning induces moderate activation of OT neurons in the paraventricular nucleus of the hypothalamus and robust activation in the supraoptic and accessory nuclei of the hypothalamus. Application of OT into the BNST dl facilitates fear learning toward signaled, predictable threats, whereas blocking OTR attenuates this effect. We conclude that OTR neurotransmission in the BNST dl plays a pivotal role in strengthening fear learning of temporally predictable, signaled threats.

In men, the incidence of melanoma rises rapidly after age 50, and nearly two thirds of melanoma deaths are male. The immune system is known to play a key role in controlling the growth and spread of malignancies, but whether age-and sex-dependent changes in immune cell function account for this effect remains unknown. Here, we show that in castrated male mice, neutrophil maturation and function are impaired, leading to elevated metastatic burden in two models of melanoma. Replacement of testosterone effectively normalized the tumor burden in castrated male mice. Further, the aberrant neutrophil phenotype was also observed in prostate cancer patients receiving androgen deprivation therapy, highlighting the evolutionary conservation and clinical relevance of the phenotype. Taken together, these results provide a better understanding of the role of androgen signaling in neutrophil function and the impact of this biology on immune control of malignancies.

Targeting inflammasome activation to modulate interleukin (IL)-1β is a promising treatment strategy against acute respiratory distress syndrome and ventilator-induced lung injury (VILI). Autophagy is a key regulator of inflammasome activation in macrophages. Here, we investigated the role of autophagy in the development of acute lung injury (ALI) induced by lipopolysaccharide (LPS) and mechanical ventilation (MV). Two hours before starting MV, 0.2 mg/kg LPS was administered to mice intratracheally. Mice were then placed on high-volume MV (30 ml/kg with 3 cmH 2 O positive end-expiratory pressure for 2.5 h without additional oxygen application). Mice with myeloid-specific deletion of the autophagic protein ATG16L1 (Atg16l1 fl/fl LysM Cre ) suffered severe hypoxemia (adjusted p < 0.05) and increased lung permeability (p < 0.05, albumin level in bronchoalveolar lavage fluid) with significantly higher IL-1β release into alveolar space (p < 0.05). Induction of autophagy by fasting-induced starvation led to improved arterial oxygenation (adjusted p < 0.0001) and lung permeability (p < 0.05), as well as significantly suppressed IL-1β production (p < 0.01). Intratracheal treatment with anti-mouse IL-1β monoclonal antibody (mAb; 2.5 mg/kg) significantly improved arterial oxygenation (adjusted p < 0.01) as well as lung permeability (p < 0.05). On the other hand, deletion of IL-1α gene or use of anti-mouse IL-1α mAb (2.5 mg/kg) provided no significant protection, suggesting that the LPS and MV-induced ALI is primarily dependent on IL-1β, but independent of IL-1α. These observations suggest that autophagy has a protective role in controlling inflammasome activation and production of IL-1β, which plays a critical role in developing hypoxemia and increased lung permeability in LPS plus MV-induced acute lung injury.