Amyloid precursor protein induces reactive astrogliosis.

We present in vitro and in vivo evidence demonstrating that Amyloid Precursor Protein (APP) acts as an essential instigator of reactive astrogliosis. Cell-specific overexpression of APP in cultured astrocytes led to remodelling of the intermediate filament network, enhancement of cytokine production and activation of cellular programs centred around the interferon (IFN) pathway, all signs of reactive astrogliosis. Conversely, APP deletion in cultured astrocytes abrogated remodelling of the intermediate filament network and blunted expression of IFN stimulated gene (ISG) products in response to lipopolysaccharide (LPS). Following traumatic brain injury (TBI), mouse reactive astrocytes also exhibited an association between APP and IFN, while APP deletion curbed the increase in glial fibrillary acidic protein (GFAP) observed canonically in astrocytes in response to TBI. Thus, APP represents a molecular inducer and regulator of reactive astrogliosis.

Sun-safe practices in U.S. youth and their parents: role of caregiver on youth sunscreen use.

BACKGROUND: There is a limited understanding of the social influences, such as the role of parents on youth sun-safe practices, that may reduce the risk of developing skin cancer later in life. METHODS: This study examined the degree of correlation in sun-safe practices between youth and their parents and assessed independent parental factors of youth sunscreen use in a 1998 cross-sectional, population-based telephone survey of U.S. youth (11- to 18-year-olds) and their parents/caregivers (N=1192 pairs of youth and parents). RESULTS: Sunscreen-use practices between youth and their parents were significantly correlated, albeit small. Youth were significantly more likely to use sunscreen frequently if their parents applied it frequently on themselves. Multivariate analysis revealed three independent parental factors associated with frequent youth sunscreen use: Their parent reported to insist frequently that the child uses sunscreen (adjusted prevalence odds ratio [aPOR]=2.4, 95% confidence interval [CI], 1.6-3.8); parent reported no difficulty with protecting their child from the sun (aPOR=1.4, 95% CI, 1.1-1.9); and parent's own frequency of sunscreen use (aPOR=1.3, 95% CI, 0.9-1.8). CONCLUSIONS: Sun-safe practices were correlated between parent-child pairs and parental factors exerted a positive role on youth sunscreen-use frequency. These data may guide further sociobehavioral and intervention research for the design of skin cancer prevention programs in schools and communities to improve levels of sun-safe practices.