RESUMO
Astrocytes have critical functions throughout the central nervous system (CNS) and have emerged as regulators of synaptic development and function. With their highly complex morphologies, they are able to interact with thousands of synapses via peripheral astrocytic processes (PAPs), ensheathing neuronal axons and dendrites to form the tripartite synapse. In this way, astrocytes engage in crosstalk with neurons to mediate a variety of CNS processes including the regulation of extracellular matrix protein signaling, formation and maintenance of the blood-brain barrier (BBB), axon growth and guidance, homeostasis of the synaptic microenvironment, synaptogenesis, and the promotion of synaptic diversity. In this review, we discuss several key astrocyte signaling factors (thrombospondins, netrins, apolipoproteins, neuregulins, bone morphogenetic proteins, and neuroligins) in the maintenance and regulation of synapse formation. We also explore how these astrocyte signaling factors are impacted by and contribute to substance abuse, particularly alcohol and cocaine use.
Assuntos
Apolipoproteínas/metabolismo , Astrócitos/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Netrinas/metabolismo , Neurregulinas/metabolismo , Sinapses/metabolismo , Trombospondinas/metabolismo , Transtornos Relacionados ao Uso de Álcool/metabolismo , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Humanos , Receptores Pré-Sinápticos/metabolismo , Transdução de Sinais/fisiologiaRESUMO
Infections caused by carbapenemase-producing Klebsiella pneumoniae resistant to tigecycline, colistin, or aminoglycosides are a growing health concern. In our retrospective chart review, we noted increased resistance to colistin compared with tigecycline, despite limited prior use of colistin. This may affect the choice of presumptive antibiotics used in these hard to treat infections. Improved infection control and antimicrobial stewardship practices are essential to prevent the spread of these multidrug-resistant organisms.
