The critical role of the endolysosomal system in cerebral ischemia.

Cerebral ischemia is a serious disease that triggers sequential pathological mechanisms, leading to significant morbidity and mortality. Although most studies to date have typically focused on the lysosome, a single organelle, current evidence supports that the function of lysosomes cannot be separated from that of the endolysosomal system as a whole. The associated membrane fusion functions of this system play a crucial role in the biodegradation of cerebral ischemia-related products. Here, we review the regulation of and the changes that occur in the endolysosomal system after cerebral ischemia, focusing on the latest research progress on membrane fusion function. Numerous proteins, including N-ethylmaleimide-sensitive factor and lysosomal potassium channel transmembrane protein 175, regulate the function of this system. However, these proteins are abnormally expressed after cerebral ischemic injury, which disrupts the normal fusion function of membranes within the endolysosomal system and that between autophagosomes and lysosomes. This results in impaired "maturation" of the endolysosomal system and the collapse of energy metabolism balance and protein homeostasis maintained by the autophagy-lysosomal pathway. Autophagy is the final step in the endolysosomal pathway and contributes to maintaining the dynamic balance of the system. The process of autophagosome-lysosome fusion is a necessary part of autophagy and plays a crucial role in maintaining energy homeostasis and clearing aging proteins. We believe that, in cerebral ischemic injury, the endolysosomal system should be considered as a whole rather than focusing on the lysosome. Understanding how this dynamic system is regulated will provide new ideas for the treatment of cerebral ischemia.

Early active immunization with Aß3-10-KLH vaccine reduces tau phosphorylation in the hippocampus and protects cognition of mice.

Active and passive anti-Aß immunotherapies have successfully been used for the prevention and treatment of Alzheimer's disease animal models. However, clinical use of these immunotherapies is not effective, because the vaccination is administered too late. At 1 month of age, 100 µL of Aß3-10-KLH peptide (vaccine, 2 µg/µL) was subcutaneously injected into the neck of an amyloid precursor protein/presenilin-1/tau transgenic (3×Tg-AD) mouse model. Aß3-10-KLH peptide was re-injected at 1.5, 2.5, 3.5, 4.5, 5.5, and 6.5 months of age. Serum levels of Aß antibody were detected by enzyme-linked immunosorbent assay, while spatial learning and memory ability were evaluated by Morris water maze. Immunohistochemistry was used to detect total tau with HT7 and phosphorylated tau with AT8 (phosphorylation sites Ser202 and Thr205) and AT180 (phosphorylation site Thr231) antibodies in the hippocampus. In addition, western blot analysis was used to quantify AT8 and AT180 expression in the hippocampus. The results showed that after vaccine injection, mice produced high levels of Aß antibody, cognitive function was significantly improved, and total tau and phosphorylated tau levels were significantly reduced. These findings suggest that early active immunization with Aß3-10-KLH vaccine can greatly reduce tau phosphorylation, thereby mitigating the cognitive decline of 3×Tg-AD mice. This study was approved by the Animal Ethics Committee of China Medical University, China (approval No. 103-316) on April 2, 2016.

Reduction of amyloid beta by Aß3-10-KLH vaccine also decreases tau pathology in 3×Tg-AD mice.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive amyloid-ß (Aß) accumulation, neurofibrillary tangles (NFTs) formation and synaptic alterations. Active immunotherapy is regarded as one of the most promising strategies for AD prevention and treatment. In this research, we used APPswe/PS1M146 V/TauP301 L triple transgenic (3×Tg-AD) mice, in which the pathological changes are the most similar to those in AD patients. The Aß 3-10 -keyhole limpet haemocyanin (KLH) vaccine was administered to mice at 1 month, and no AD-associated changes were detected at that time. The vaccine effectively mitigated AD-like pathology and cognitive dysfunction in the 3×Tg-AD mice. Both soluble and insoluble Aß and tau protein in the brain tissues of the 3×Tg-AD mice were significantly decreased after the administration of Aß 3-10 -KLH. In addition, the level of phosphorylated tau also decreased following removal of the Aß pathological changes.

An Aß3-10-KLH vaccine reduced Alzheimer's disease-like pathology and had a sustained effect in Tg-APPswe/PSEN1dE9 mice.

Alzheimer's disease is a neurodegenerative disease that affects many patients worldwide. The amyloid cascade hypothesis has been adopted by most researchers as the mechanism underlying Alzheimer's disease. Aß plaques have been considered the core factor in the neurotoxic effect in Alzheimer's disease, though some controversy remains. Further effort is necessary to elucidate the mechanism and to develop effective treatments. Previous studies have indicated that eliminating Aß plaques could improve synaptic plasticity and cognitive function. Researchers have developed various forms of vaccines to prevent Aß deposition or eliminate Aß plaques and have made some progress. We developed a new vaccine, Aß3-10-KLH, to increase the level of the anti-Aß immune response, and we show that this vaccine resulted in a sustained prevention of Aß deposition at 4 months after cessation of the vaccine treatment. At the same time point, the expression of synaptophysin and NMDAR2B in APP/PS1 transgenic mice was increased by immunization.

Prophylactic active immunization with a novel epitope vaccine improves cognitive ability by decreasing amyloid plaques and neuroinflammation in APP/PS1 transgenic mice.

Both amyloid-ß peptide (Aß) deposition and neuroinflammation are considered to be early events that play pivotal roles in Alzheimer's disease (AD) pathogenesis and its associated cognitive impairment. Prophylactic anti-Aß active immunotherapy is a promising therapeutic strategy for AD, if the Aß-specific autoimmune responses to self T cell epitopes of Aß can be avoided. This can be achieved by the use of antigen, which contains the B cell epitope of Aß and excludes the Aß-specific T cell epitope. In this study, we developed a novel peptide epitope vaccine, Aß3-10-KLH, by coupling the B cell epitope Aß3-10 to keyhole limpet hemocyanin (KLH) as the carrier protein, and subcutaneously injected it into 2.5-month-old APP/PS1 transgenic mice. Aß3-10-KLH immunization induced high levels of anti-Aß antibodies and significantly improved cognitive ability in APP/PS1 transgenic mice. Immunohistochemistry and immunofluorescence revealed that Aß3-10-KLH immunization significantly reduced cerebral amyloid plaque formation and alleviated gliosis. The results indicate that Aß3-10-KLH immunization successfully rescued cognitive impairment in APP/PS1 transgenic mice via decreasing cerebral Aß deposition and neuroinflammation. Aß3-10-KLH may potentially be safe and effective for prevention and treatment of AD.

In Situ Multitechnical Investigation into Capacity Fading of High-Voltage LiNi0.5Co0.2Mn0.3O2.

LiNi0.5Co0.2Mn0.3O2 positive electrode materials of lithium ion battery can release a discharge capacity larger than 200 mAh/g at high potential (>4.30 V). However, its inevitable capacity fading, which is greatly related to the structural evolution, reduces the cycling performance. The origin of this capacity fading is investigated by coupled in situ XRD-PITT-EIS. A new phase of NiMn2O4 is discovered on the surface of the LiNi0.5Co0.2Mn0.3O2 upon charging to high voltage, which blocks Li+ diffusion pathways. Theoretical calculations predict the formation of cubic NiMn2O4. Moreover, corrosion, cracks, and microstress appear to increase the difficulty of Li+ transportation, which are attributed to the protection degradation of the interfacial film on the positive electrode material at high voltage. After 50 electrochemical cycles, the increase in degree of crystal defects by low-angle grain boundary, evidenced through HR-TEM, leads to poor Li+ kinetics, which in turn causes capacity loss. The in situ XRD-PITT-EIS technique can bring multiperspective insights into fading mechanism of the high-voltage positive electrode materials and provide a solution to control or suppress the problem on the basis of structural, kinetic, and electrochemical interfacial understandings.

Active immunization with the peptide epitope vaccine Aß3-10-KLH induces a Th2-polarized anti-Aß antibody response and decreases amyloid plaques in APP/PS1 transgenic mice.

Active amyloid-ß (Aß) immunotherapy is effective in preventing Aß deposition, facilitating plaque clearance, and improving cognitive functions in mouse models of Alzheimer's disease (AD). Developing a safe and effective AD vaccine requires a delicate balance between inducing adequate humoral immune responses and avoiding T cell-mediated autoimmune responses. In this study, we designed 2 peptide epitope vaccines, Aß3-10-KLH and 5Aß3-10, prepared respectively by coupling Aß3-10 to the immunogenic carrier protein keyhole limpet hemocyanin (KLH) or by joining 5 Aß3-10 epitopes linearly in tandem. Young APP/PS1 mice were immunized subcutaneously with Aß3-10-KLH or 5Aß3-10 mixed with Freund's adjuvant, and the immunopotencies of these Aß3-10 peptide vaccines were tested. Aß3-10-KLH elicited a robust Th2-polarized anti-Aß antibody response and inhibited Aß deposition in APP/PS1 mice. However, 5Aß3-10 did not induce an effective humoral immune response. These results indicated that Aß3-10-KLH may be a safe and efficient vaccine for AD and that conjugating the antigen to a carrier protein may be more effective than linking multiple peptide antigens in tandem in applications for antibody production and vaccine preparation.