MicroRNA alterations have been reported in patients with Alzheimer＇s disease （AD） and AD mouse models. We now report that miR-206 is upregulated in the hippocampal tissue, cerebrospinal fluid, and plasma of embryonic APP/PS1 transgenic mice. The increased miR-206 downregulates the expression of brain-derived neurotrophic factor （BDNF）. BDNF is neuroprotective against cell death after various insults, but in embryonic and newborn APP/PS1 mice it is decreased. Thus, a specific microRNA alteration may contribute to AD pathology by downregulating BDNF.
The tunneling nanotube （TNT） is a newly discovered, long and thin tubular structure between cells. In this study, we established a co-culture system for rat primary astrocytes and C6 glioma cells and found that TNTs formed between them. Most of the TNTs initiated from astrocytes towards C6 glioma cells. The formation of TNTs depended on p53. In addition, hydrogen peroxide increased the number of TNTs in the co-culture system. Established TNTs reduced the proliferation of C6 glioma cells. Our data suggest that TNTs between astrocytes and glioma cells facilitate substance transfer and therefore alter the properties, including the proliferation potential, of glioma cells.
Objective Curcumin is extracted from the turmeric plant （Curcuma longa Linn.） and is widely used as a food additive and traditional medicine. The present study investigated the activity of curcumin against staurosporine （STS） toxicity in cell culture. Methods Rat hippocampal neurons in primary culture were exposed to STS （20 μmol/L） and treated with curcumin （20 μmol/L）. Cell viability was tested by MTT assay and reactive oxygen species （ROS） were measured using the MitoSOX red mitochondrial superoxide indicator. Western blot was used to assess changes in the levels of caspase-3 （Csp3）, heat shock protein 70 （Hsp70） and Akt. Results The results showed that curcumin protects against STS-induced cytotoxicity in rat hippocampal neurons. Csp3, Hsp70, Akt and ROS activation may be involved in this protection. Conclusion Curcumin could be a potential drug for combination with STS in cancer treatment to reduce the unwanted cytotoxicity of STS.
