[Effect of electroacupuncture on recognition memory and levels of Aß, inflammatory factor proteins and aquaporin 4 in hippocampus of APP/PS1 double transgenic mice].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) at "Baihui "(GV20) and "Shenshu "(BL23) on activation of glial cells, expression of inflammatory factor proteins and aquaporin 4 (AQP4)in the hippocampus of amyloid precursor protein/presenilin-1 (APP/PS1) transgenic mice, so as to explore its mechanisms underlying improvement of Alzheimer's disease(AD). METHODS: Twenty C57/BL6 background male APP695/PS1-dE9(APP/PS1) double transgenic mice (model group) and 20 wild type (WT) C57/BL6 mice (blank group) were respectively randomized into control and EA groups. EA (2 Hz/15 Hz, 1－2 mA) was applied to GV20 and bilateral BL23 for 30 min, once daily, 6 days a week for 4 weeks. The recognition memory ability was detected by novel object recognition tests in a behavior test box. The percentage of time spent in close interaction with novel object (C) relative to the total time was used to generate preference index. The contents of hippocampal ß amyloid protein (Aß)1-40 and Aß1-42 were assayed using ELISA, and the expression levels of glial fibrillary acidic protein (GFAP), ionic calcium binding receptor molecule-1 (Iba-1), interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) proteins in the hippocampus measured by Western blot. The activities of hippocampal astrocytes (GFAP-labelled cells), microglia (Iba-1-labelled cells) and the polarity expression of AQP4 (for removing Aß) were measured by immunohistochemistry. RESULTS: The preference index was significantly decreased in the model group relatively to the blank control group (P<0.05) and considerably increased in the model＋EA group relatively to the model group (P<0.05), suggesting an improvement of the recognition memory after EA. The contents of Aß1-40 and Aß1-42, immunoactivity of GFAP and Iba-1, expression levels of GFAP, Iba-1, IL-1ß, IL-6 and TNF-α proteins were significantly higher in the model group than in the blank control group (P<0.01，P<0.05), while the AQP4 immunoactivity was notably lower in the model group than in the blank control group (P<0.05). Compared with the model group, the levels of Aß1-40 and Aß1-42, GFAP, Iba-1, IL-1ß, IL-6 and TNF-α proteins, and the percentage of Aß plaque area were significantly decreased in the model＋EA group (P<0.01，P<0.05), and the immunoactivity of AQP4 was significantly increased in the mo-del＋EA group (P<0.05). No significant changes were found in the above-mentioned indexes in the blank＋EA group relevant to the blank control group (P>0.05)．. CONCLUSION: EA at GV20 and BL23 can reduce inflammatory reaction and Aß level, suppress activation of astrocytes and microglia, and up-regulate expression of AQP4 in the hippocampus tissue in APP/PS1 transgenic mice, which may contribute to its effect in improving recognition memory ability, suggesting a role of EA intervention in delaying the development of AD via promoting the drainage of Aß by the glymphatic system in the brain.

Neural differentiation of human Wharton's jelly-derived mesenchymal stem cells improves the recovery of neurological function after transplantation in ischemic stroke rats.

Human Wharton's jelly-derived mesenchymal stem cells (hWJ-MSCs) have excellent proliferative ability, differentiation ability, low immunogenicity, and can be easily obtained. However, there are few studies on their application in the treatment of ischemic stroke, therefore their therapeutic effect requires further verification. In this study, hWJ-MSCs were transplanted into an ischemic stroke rat model via the tail vein 48 hours after transient middle cerebral artery occlusion. After 4 weeks, neurological functions of the rats implanted with hWJ-MSCs were significantly recovered. Furthermore, many hWJ-MSCs homed to the ischemic frontal cortex whereby they differentiated into neuron-like cells at this region. These results confirm that hWJ-MSCs transplanted into the ischemic stroke rat can differentiate into neuron-like cells to improve rat neurological function and behavior.

A cell-based high-throughput screen for epidermal growth factor receptor pathway inhibitors.

Epidermal growth factor receptor (EGFR) is a valid drug target for development of target-based therapeutics against non-small-cell lung cancer. In this study, we established a high-throughput cell-based assay to screen for compounds that may inhibit EGFR activation and/or EGFR-mediated downstream signaling pathway. This drug screening platform is based on the characterization of an EGFR-transfected 32D cell line (32D-EGFR). The expression of EGFR in 32D cells allowed cell proliferation in the presence of either epidermal growth factor (EGF) or interleukin 3 (IL-3) and provided a system for both screening and counterscreening of EGFR pathway-inhibitory compounds. After the completion of primary and secondary screenings in which 32D-EGFR cells were grown under the stimulation of either EGF or IL-3, 9 of 20,000 compounds were found to selectively inhibit the EGF-dependent proliferation, but not the IL-3-dependent proliferation, of 32D-EGFR cells. Subsequent analysis showed that 3 compounds of the 9 initial hits directly inhibited the kinase activity of recombinant EGFR in vitro and the phosphorylation of EGFR in H1299 cells transfected with EGFR. Thus, this 32D-EGFR assay system provides a promising approach for identifying novel EGFR and EGFR signaling pathway inhibitors with potential antitumor activity.