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The neuropeptide galanin and its receptors are found to be upregulated in brain associated with Alzheimer's disease (AD), while the role of galanin in AD is still unclear. The present study was performed to explore the neuroprotective role of galanin both in vitro and in vivo. Our results demonstrated that galanin inhibited the neurotoxicity induced by amyloid-β25-35 (Aβ25-35) or Aβ1-42 in primary cultured hippocampal neurons of rats. Moreover, Gal2-11 (an agonist of GalR2/3) also inhibited the neurotoxicity induced by Aβ25-35 in the cultured neurons. We further found that galanin inhibited the activation of p53, Bax, and caspase-3 induced by Aβ25-35 in the cultured hippocampal neurons. Moreover, galanin reversed the down regulation of Bcl-2 induced by Aβ25-35 in the cultured neurons. Interestingly, in the Morris water maze task we found that intra-CA1 injection of Aβ25-35-induced spatial learning deficits in rats were blocked by galanin. In addition, galanin inhibited the Aβ25-35-induced dysregulation of p53, Bax, and MAP2 in rat hippocampus. Our results strongly demonstrate that galanin plays neuroprotective roles in nerve cells and in AD-induced learning and memory deficits. [ABSTRACT FROM AUTHOR]

Abstract  The central nervous system (CNS) is highly dependent on adequate supply of oxygen and is sensitive to hypoxia. It is known that hypoxia induces injuries on the brain tissue and the neuronal activity. Curcumin, a yellow pigment obtained from the rhizome of C. longa Linn., has been regarded as a multi-functional drug with antioxidative activity. In the present study, we first demonstrated a significant decrease in the content of β-III tubulin protein in rat prefrontal cortex (PFC) tissues induced by repeated hypoxia, but not in rat cerebellum tissue. These suggest a relatively higher sensitivity and probably a higher vulnerability of rat PFC tissue to hypoxia in vivo. We reconfirmed the effect of hypoxia to primary cultured neurons from rat PFC and found a significant decrease in the contents of β-III tubulin protein after chronic exposure to hypoxia. Moreover, we demonstrated that the hypoxia-induced decrease in β-III tubulin protein content could be restored by curcumin, suggesting a potential protection of curcumin against hypoxia-induced decreases in beta-III tubulin content in rat PFC neurons. [ABSTRACT FROM AUTHOR]

The article explores the application of single-cell microinjection in cell biology. The authors discuss the advantages and limits of microinjection as a mechanical transduction delivery method as well as the applications of single-cell microinjection in cell transduction and in suspended and attached cells.

Morphine has received intensive research interest for a long time. However, until recently, the protective versus destructive roles of morphine in the neuronal system have not been studied. There is evidence suggesting that morphine induces apoptotic cell death in neuronal and glial cells, whereas controversial studies support a neuroprotective role for morphine. The exact mechanisms for both protective and destructive pathways are not clear and are still under investigation. Improved understanding of morphine neuroprotection and neurotoxicity will be helpful to control morphine side effects in medical applications and to identify new targets for potential therapies and prevention strategies to opioid addiction. [ABSTRACT FROM AUTHOR]

The present study investigated the effect of intrathecal injection of (RS)-2-α-amino-3-(3-hydroxy-5-tbutylisoxazol-4-yl) propanoic acid (ATPA), a selective agonist to kainate receptor, on nociception in rats. Intrathecal administration of 1, 4 and 10 nmol of ATPA induced dose-dependent increases in the hindpaw withdrawal latency (HWL) to thermal and mechanical stimulation in rats. Pretreatment with intrathecal injection of 300 μg of concanavalin A (ConA) to block the desensitization of kainate receptors enhanced and prolonged the anti-nociceptive effect induced by intrathecal injection of ATPA. The results suggest that the pre-synaptic kainate receptor in the primary afferent terminals is involved in the transmission of nociceptive information in dorsal horn of the spinal cord in rats. Furthermore, blocking the desensitization of kainate receptor enhanced and prolonged the ATPA-induced anti-nociceptive effects. [Copyright &y& Elsevier]

The present study explored the effect of 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside (THSG) on the staurosporine (STS)-induced toxicity in cultured rat hippocampal neurons. The results showed that administration of 200μM of THSG significantly protected against 0.3μM of STS-induced apoptosis in cultured rat hippocampal neurons tested by methyl thiazolyl tetrazolium (MTT) and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assays. Furthermore, when the Akt signaling pathway was blocked by LY294002, an inhibitor of Phosphatidyl Inositol 3-kinase (PI3K), the protective effects of THSG against STS-induced neurotoxicity were abrogated. We further examined the involvement of PI3K/Akt signaling pathway in THSG protection against STS-induced cytotoxicity on cultured neurons and found that administration of THSG significantly inhibited the STS-induced decreases in the content of phosphorylated AKt (p-Akt). Moreover, we found that THSG rescued the down-regulation of B cell lymphoma/lewkmia-2 (Bcl2) and pro-caspase-3 (pro-Csp3) caused by STS in the neurons. These results indicate that THSG protect the cultured rat hippocampal neurons against STS-induced cytotoxicity and the PI3K/Akt signaling and mitochondrial apoptotic pathways are involved in the THSG-induced protective effects. [ABSTRACT FROM AUTHOR]

Galanin and galanin receptors are upregulated in the brain regions associated with Alzheimer's disease (AD). However, the consequence of this overexpression is still unknown, particularly in human neurons. Here, we investigate the possible protective effects of galanin against intracellular amyloid-β (Aβ)_{1-42} toxicity, as well as other insults including staurosporine, etoposide, hydrogen peroxide, and serum depletion in cultured human primary neurons. The results show that galanin is protective against intracellular Aβ cytotoxicity and all of the above insults at sub-nanomolar physiological concentrations. The galanin protection may be mediated by galanin receptor 2 and down-regulation of Bax level. The data from the present study provide a potential drug target for therapy or prevention of neurodegenerative diseases, including AD. [ABSTRACT FROM AUTHOR]