Resveratrol ameliorated the behavioral deficits in a mouse model of post-traumatic stress disorder.

Post-traumatic stress disorder (PTSD) has become a major psychiatric and neurological issue. Resveratrol is shown to be effective on depression and anxiety. However, the mechanism of anti-PTSD-like effects of resveratrol remains unknown. The present study aimed to explore the possible molecular and cellular mechanisms underlying the anti-PTSD-like effects of resveratrol. Following a 2-day exposure to inescapable electric foot shocks, animals were administered resveratrol (10, 20, and 40mg/kg, i.g.) during the behavioral tests, which included contextual freezing measurement, elevated plus maze test, staircase test, and open field test. Similar to the positive control drug sertraline (15mg/kg, i.g.), the behavioral deficits of stressed mice were blocked by resveratrol (20 and 40mg/kg, i.g.), which reversed the increased freezing time in contextual freezing measurement and the number of rears in the staircase test and blocked the decrease in time and number of entries in open arms in the elevated plus maze test without affecting the locomotor activity in the open field test. In addition, resveratrol (20 and 40mg/kg, i.g.) antagonized the decrease in the levels of progesterone and allopregnanolone in the prefrontal cortex and hippocampus. Furthermore, long-term resveratrol attenuated the dysfunctions of hypothalamic-pituitary-adrenal axis simultaneously. Collectively, the evidence indicated that the anti-PTSD-like effects of resveratrol were associated with the normalization of biosynthesis of neurosteroids in the brain and prevention of the hypothalamic-pituitary-adrenal axis dysfunction.

Dihydroartemisinin increases temozolomide efficacy in glioma cells by inducing autophagy.

Artemisinin, a powerful antimalarial medicine, is extracted from the Chinese herb, Artemisia annua L., and has the ability to inhibit the proliferation of cancer cells. Dihydroartemisinin (DHA), the major active metabolite of artemisinin, is able to inhibit the growth of a variety of types of human cancer. However, the effect of DHA on human glioma cells remains unclear. The aim of the present study was to investigate the effect of DHA on the proliferation of glioma cells, and whether DHA was able to enhance temozolomide (TMZ) sensitivity in vitro and in vivo. In total, 10 human glioma cell lines were used to analyze the growth inhibition ability of DHA by MTT assay. The typical autophagic vacuoles were monitored by the application of the autofluorescent agent, monodansylcadaverine. Western blotting was used to detect markers of apoptosis and autophagy, namely Caspase-3, Beclin-1 and LC3-B. The combination efficiency of DHA and TMZ was assessed in vitro and in vivo. The half maximal inhibitory concentration (IC50) of DHA differed among the ten human glioma cell lines. The number of autophagic vacuoles was higher in DHA-treated SKMG-4 cells; this was highest of all cell lines analyzed. The expression of autophagy molecular markers, Beclin-1 and LC3-B, was increased following DHA treatment, while no significant alteration was detected in the expression of apoptotic marker Caspase-3. When combined with DHA, the IC50 of TMZ decreased significantly in the four glioma cell lines analyzed. Furthermore, DHA enhanced the tumor inhibition ability of TMZ in tumor-burdened mice. The results of the present study demonstrated that DHA inhibited the proliferation of glioma cells and enhanced the tumor inhibition efficacy of TMZ in vitro and in vivo through the induction of autophagy.

Effect of rat Schwann cell secretion on proliferation and differentiation of human neural stem cells.

OBJECTIVE: To investigate the effect of rat Schwann cell secretion on the proliferation and differentiation of human embryonic neural stem cells (NSCs). METHODS: The samples were divided into three groups. In Group One, NSCs were cultured in DMED/F12 in which Schwann cells had grown for one day. In Group Two, NSCs and Schwann cells were co-cultured. In Group Three, NSCs were cultured in DMEM/F12. The morphology of NSCs was checked and beta-tubulin, GalC, hoechst 33342 and GFAP labellings were detected. RESULTS: In Group One, all neural spheres were attached to the bottom and differentiated. The majority of them were beta-tubulin positive while a few of cells were GFAP or GalC positive. In Group Two, neural spheres remained undifferentiated and their proliferation was inhibited in places where Schwann cells were robust. In places where there were few Schwann cells, NSCs performed in a similar manner as in Group One. In Group Three, the cell growth state deteriorated day after day. On the 7th day, most NSCs died. CONCLUSION: The secretion of rat Schwann cells has a growth supportive and differentiation-inducing effect on human NSCs.