RESUMO
Reductions in hippocampal neurite complexity and synaptic plasticity are believed to contribute to the progressive impairment in episodic memory and the mild cognitive decline that occur particularly in the early stages of Alzheimer's disease (AD). Despite the functional and therapeutic importance for patients with AD, intervention to rescue or normalize dendritic elaboration and synaptic plasticity is scarcely provided. Here we show that overexpression of neuritin, an activity-dependent protein, promoted neurite outgrowth and maturation of synapses in parallel with enhanced basal synaptic transmission in cultured hippocampal neurons. Importantly, exogenous application of recombinant neuritin fully restored dendritic complexity as well as spine density in hippocampal neurons prepared from Tg2576 mice, whereas it did not affect neurite branching of neurons from their wild-type littermates. We also showed that soluble recombinant neuritin, when chronically infused into the brains of Tg2576 mice, normalized synaptic plasticity in acute hippocampal slices, leading to intact long-term potentiation. By revealing the protective actions of soluble neuritin against AD-related neural defects, we provide a potential therapeutic approach for patients with AD.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Proteínas do Tecido Nervoso/farmacologia , Fármacos Neuroprotetores/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Dendritos/efeitos dos fármacos , Dendritos/metabolismo , Dendritos/ultraestrutura , Modelos Animais de Doenças , Proteínas Ligadas por GPI/biossíntese , Proteínas Ligadas por GPI/farmacologia , Expressão Gênica , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Masculino , Camundongos , Microtomia , Proteínas do Tecido Nervoso/biossíntese , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neuritos/ultraestrutura , Plasticidade Neuronal/efeitos dos fármacos , Fármacos Neuroprotetores/metabolismo , Cultura Primária de Células , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Sinapses/efeitos dos fármacos , Técnicas de Cultura de TecidosRESUMO
A Korean nationwide surveillance on circulating rotavirus strains was conducted from September 2000 to August 2007 aiming to obtain prevaccine data for predicting vaccine effectiveness. The predominant strains among the 2779 strains analyzed varied annually and only approximately 50% had either a G or a P antigen present in both RotaTeq (Merck & Co. Inc., Whitehouse Station, NJ, USA) and Rotarix (GlaxoSmithKline, Brentford, UK).
Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Genótipo , Humanos , República da Coreia/epidemiologia , Rotavirus/isolamento & purificação , Vacinas contra Rotavirus/imunologiaRESUMO
The present study was conducted to survey the prevalence and genotypic distribution of human astrovirus (HAstV) circulating in South Korea. Of 160,027 patients with acute gastroenteritis, 2,057 (1.3%) were positive for HAstV antigen. We determined the genotypes of 187 HAstV strains collected from laboratories across the country. Genetic analysis revealed genotype 1 to be the most prevalent, accounting for 72.19% of the strains, followed by genotypes 8 (9.63%), 6 (6.95%), 4 (6.42%), 2 (3.21%) and 3 (1.60%). Our findings indicate that HAstV is less common but, even so, a potentially important viral agent of gastroenteritis in South Korea, with significant genetic diversity among circulating HAstV strains.
