Acute stress impairs sensorimotor gating via the neurosteroid allopregnanolone in the prefrontal cortex

Ample evidence indicates that environmental stress impairs information processing, yet the underlying mechanisms remain partially elusive. We showed that, in several rodent models of psychopathology, the neurosteroid allopregnanolone (AP) reduces the prepulse inhibition (PPI) of the startle, a well-validated index of sensorimotor gating. Since this GABAA receptor activator is synthesized in response to acute stress, we hypothesized its participation in stress-induced PPI deficits. Systemic AP administration reduced PPI in C57BL/6J mice and Long-Evans, but not Sprague-Dawley rats. These effects were reversed by isoallopregnanolone (isoAP), an endogenous AP antagonist, and the GABAA receptor antagonist bicuculline and mimicked by AP infusions in the medial prefrontal cortex (mPFC). Building on these findings, we tested AP's implication in the PPI deficits produced by several complementary regimens of acute and short-term stress (footshock, restraint, predator exposure, and sleep deprivation). PPI was reduced by acute footshock, sleep deprivation as well as the combination of restraint and predator exposure in a time- and intensity-dependent fashion. Acute stress increased AP concentrations in the mPFC, and its detrimental effects on PPI were countered by systemic and intra-mPFC administration of isoAP. These results collectively indicate that acute stress impairs PPI by increasing AP content in the mPFC. The confirmation of these mechanisms across distinct animal models and several acute stressors strongly supports the translational value of these findings and warrants future research on the role of AP in information processing

Human β-defensin-2 suppresses key features of asthma in murine models of allergic airways disease.

BACKGROUND:Asthma is an airway inflammatory disease and a major health problem worldwide. Anti-inflammatory steroids and bronchodilators are the gold-standard therapy for asthma. However, they do not prevent the development of the disease, and critically, a subset of asthmatics are resistant to steroid therapy. OBJECTIVE:To elucidate the therapeutic potential of human β-defensins (hBD), such as hBD2 mild to moderate and severe asthma. METHODS:We investigated the role of hBD2 in a steroid-sensitive, house dust mite-induced allergic airways disease (AAD) model and a steroid-insensitive model combining ovalbumin-induced AAD with C muridarum (Cmu) respiratory infection. RESULTS:In both models, we demonstrated that therapeutic intranasal application of hBD2 significantly reduced the influx of inflammatory cells into the bronchoalveolar lavage fluid. Furthermore, key type 2 asthma-related cytokines IL-9 and IL-13, as well as additional immunomodulating cytokines, were significantly decreased after administration of hBD2 in the steroid-sensitive model. The suppression of inflammation was associated with improvements in airway physiology and treatment also suppressed airway hyper-responsiveness (AHR) in terms of airway resistance and compliance to methacholine challenge. CONCLUSIONS AND CLINICAL RELEVANCE:These data indicate that hBD2 reduces the hallmark features and has potential as a new therapeutic agent in allergic and especially steroid-resistant asthma

Síndrome da unha amarela Yellow nail syndrome

A síndrome da unha amarela é uma entidade clínica rara caracterizada por três achados principais: alterações distróficas e de coloração das unhas, linfedema e derrame pleural. Bronquiectasias e rinossinusite crônica têm sido freqüentemente associadas. Relatamos o caso de uma paciente com os achados completos da síndrome, com derrame pleural bilateral e que estava em tratamento de tuberculose pulmonar havia nove meses. Na sua história familiar havia a descrição de dois casos semelhantes, em irmã e irmão.<br>Yellow nail syndrome is a rare disorder characterized by three main features: discoloration of the nails, together with dystrophic alterations; lymphedema; and pleural effusion. It is often accompanied by bronchiectasis and chronic rhinosinusitis. Herein, we report a case of the complete syndrome with bilateral pleural effusion in a patient under treatment for pulmonary tuberculosis for nine months. There was a family history of two similar cases in siblings