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Neurovascular degeneration contributes to the pathogenesis of Alzheimer's disease (AD). Because erythropoietin (EPO) promotes endothelial regeneration, we investigated the therapeutic effects of EPO in animal models of AD. In aged Tg2576 mice, EPO receptors (EPORs) were expressed in the cortex and hippocampus. Tg2576 mice were treated with daily injection of EPO (5000 IU/kg/day) for 5 days. At 14 days, EPO improved contextual memory as measured by fear-conditioning test. EPO enhanced endothelial proliferation and the level of synaptophysin expression in the brain. EPO also increased capillary density, and decreased the level of the receptor for advanced glycation endproducts (RAGE) in the brain, while decreasing in the amount of amyloid plaque and amyloid-β (Aβ). In cultured human endothelial cells, EPO enhanced angiogenesis and suppressed the expression of the RAGE. These results show that EPO improves memory and ameliorates endothelial degeneration induced by Aβ in AD models. This pre-clinical evidence suggests that EPO may be useful for the treatment of AD.

Summary Purpose: Stem cell–based therapies are being considered for various neurologic diseases, such as epilepsy. Recent studies have suggested that some effects of transplanted stem cells are due to bystander effects that modulate the host environment, rather than direct effects of cell replacement. The extract from human adipose stem cells (ASCs) that secrete multiple growth factors including cytokines and chemokines may be a potential source of bystander effects for the treatment of epilepsy, in which inflammation is thought to play an important role. Here, we investigated the effects of a cytosolic extract of human ASCs (ASCs-E) in a mouse model of epilepsy. Methods: Human ASCs-E, boiled ASCs-E, or fibroblast-extract (fibroblast-E) was intraperitoneally administrated to C57BL/6 mice 15 min before pilocarpine-induced status epilepticus (SE) or during chronic epileptic stage. Blood–brain barrier (BBB) leakage was evaluated by measuring Evans blue dye extravasation. Spontaneous recurrent seizure (SRS) was investigated by long-term video–electroencephalography (EEG) monitoring. The mice performed elevated plus maze, open-field, light/dark transition, and novel object recognition tasks. Key Findings: Acute application of human ASCs-E before SE led to earlier attenuation of seizure spike activities after treatment with diazepam, reduction of BBB leakage, and inhibition of the development of epilepsy. Human ASCs-E treatment (for 7 days) during the chronic epileptic stage suppressed SRS and reduced abnormal epileptic behavioral phenotypes. However, neither boiled ASCs-E nor fibroblast-E had any effects in the experimental epilepsy model. Significance: Our results demonstrate that human ASCs-E prevents or inhibits epileptogenesis and SRS in mice. They also suggest a stem cell–based, noninvasive therapy for the treatment of epilepsy.

Summary Purpose: Children who experience complex febrile seizures are at a higher risk of subsequent epileptic episodes, and they may require therapy. This issue can be resolved by interventional studies using molecular targets identified and defined in animal models. In the current study, the molecular changes in the rat brain after febrile seizures were examined throughout the latent period, and erythropoietin was administered as a potentially antiepileptogenic intervention. Methods: The changes in the expressions of genes that were differentially regulated during the latent period after febrile seizures were categorized into the following four patterns: (1) continuously high (CH); (2) continuously low (CL); (3) rise and fall (RF); and (4) going-up (GU). Erythropoietin was administered immediately after seizure cessation and then once daily for at most 7 days, and spontaneous recurrent seizures and cellular and molecular changes were investigated. Key Findings: The CH genes were associated with cell cycle and adhesion, whereas the CL genes were related to energy metabolism. Within the category of RF, the largest changes were for genes involved in inflammation, apoptosis, and γ-aminobutyric acid (GABA) signaling. The GU category included genes involved in ion transport and synaptogenesis. Along with an early rise in inflammatory genes, there were substantial increases in brain edema and activated microglia during the early latent period. Erythropoietin reduced the early inflammatory responses and modulated the molecular alterations after febrile seizures, thereby reducing the risk of subsequent spontaneous seizures. Significance: Erythropoietin treatment may provide a new strategy for preventing epilepsy in susceptible individuals with atypical febrile seizures.

Voltage-dependent N-type Ca(2+) channels, along with the P/Q-type, have a crucial role in controlling the release of neurotransmitters or neuromodulators at presynaptic terminals. However, their role in hippocampus-dependent learning and memory has never been examined. Here, we investigated hippocampus-dependent learning and memory and synaptic plasticity at hippocampal CA3-CA1 synapses in mice deficient for the alpha(1B) subunit of N-type Ca(2+) channels. The mutant mice exhibited impaired learning and memory in the Morris water maze and the social transmission of food preference tasks. In particular, long-term memory was impaired in the mutant mice. Interestingly, among activity-dependent long-lasting synaptic changes, theta burst- or 200-Hz-stimulation-induced long-term potentiation (LTP) was decreased in the mutant, compared with the wild-type mice. This type of LTP is known to require brain-derived neurotrophic factor (BDNF). It was found that both BDNF-induced potentiation of field excitatory postsynaptic potentials and facilitation of the frequency of miniature excitatory postsynaptic currents (mEPSCs) were reduced in the mutant. Taken together, these results demonstrate that N-type Ca(2+) channels are required for hippocampus-dependent learning and memory, and certain forms of LTP.