J. Neurochem. (2012) 122, 800–811. Abstract 7,8‐dihydroxyflavone (7,8‐DHF) has recently been identified as a potential TrkB agonist that crosses the blood–brain barrier after i.p. administration. We previously demonstrated that 7,8‐DHF in vitro rescues long‐term synaptic plasticity in the hippocampus of aged rats. This study assessed the rescue effect of 7,8‐DHF in vivo on aging‐related cognitive impairment in rats, and further determined whether the effect of 7,8‐DHF is age dependent. Aged rats at 22 and 30 months of age were pretested for spatial memory in Morris water maze. The aged‐impaired rats were retested twice during 7,8‐DHF or vehicle treatment, which started 3 weeks after the completion of the pretest. In the 22‐month‐old rats, daily i.p. administration of 7,8‐DHF for 2 weeks improved spatial memory. The improvement in behavioral tests was associated with increases in synapse formation and facilitation of synaptic plasticity in the hippocampus, as well as the activation of several proteins crucial to synaptic plasticity and memory. A more extended treatment paradigm with 7,8‐DHF was required to achieve a significant memory improvement in the severely impaired 30‐month‐old rats. Moreover, 7,8‐DHF moderately facilitated the synaptic plasticity, modified the density but not number of spines in the hippocampus of the oldest rats. Taken together, our results suggest that 7,8‐DHF can act in vivo to counteract aging‐induced declines in spatial memory and synaptic plasticity and morphological changes of hippocampal neurons. The effect of 7,8‐DHF is more pronounced in relatively younger impaired rats than in those of more advanced age. These findings demonstrate the reversal of age‐dependent memory impairment by in vivo 7,8‐DHF application and support the benefit of early treatment for cognitive aging.

Due to the increase in the incidence of upper gastrointestinal bleeding, the treatment methods are more and more diversified. With the popularization of endoscopic techniques and the wide range of endoscopic hemostasis methods, endoscopy has become an important method for the treatment of upper gastrointestinal bleeding, and greatly updated the treatment concept of upper gastrointestinal bleeding. In this paper, we reviewed the literature reports of endoscopic treatment of upper gastrointestinal bleeding in recent years.