Cellular and molecular neurobiology
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Cell. Mol. Neurobiol. · Nov 2011
IT delivery of ChABC modulates NG2 and promotes GAP-43 axonal regrowth after spinal cord injury.
Chondroitin sulphate proteoglycans (CSPGs) with the major component NG2 have an inhibitory effect on regeneration of damaged axons after spinal cord injury. In this study, we investigate whether the digestion of CSPGs by chondroitinase ABC (ChABC) may decrease the NG2 expression and promote axon regrowth through the lesion site. Rats underwent spinal cord compression injury and were treated with ChABC or vehicle through an intrathecal catheter delivery at 2, 3, and 4 days after injury. ⋯ Longitudinally oriented and disorganized GAP-43-labeled axons were able to infiltrate and penetrate damaged tissue. The outgrowth of GAP-43 axons after CHABC delivery was significantly longer (≤0.457 mm) when compared with the length of axons in vehicle-treated rats (≤0.046 mm). Present findings suggest that degradation of NG2 with acute IT ChABC treatment may promote ongoing (long-lasting) axonal regenerative processes at late survival (14 and 28 days), but with no significant impact on the improvement of motor function.
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Cell. Mol. Neurobiol. · Nov 2011
Neuregulin-1β prevents Ca(2+) overloading and apoptosis through PI3K/Akt activation in cultured dorsal root ganglion neurons with excitotoxicity induced by glutamate.
Neuregulin (NRG) plays an important role on the genesis and differentiation of neurons in the dorsal root ganglion (DRG). Whether NRG-1β regulates Ca(2+) homeostasis and apoptosis of cultured DRG neurons with excitotoxicity induced by Glu remains unknown. In this study, primary cultured DRG neurons were used to determine the effects of NRG-1β on Ca(2+) overload and apoptosis of DRG sensory neurons with excitotoxicity induced by Glu. ⋯ These effects could be inhibited by the presence of NRG-1β. The effects of NRG-1β could be blocked by PI3K inhibitor LY294002. These results implicated that NRG-1β could prevents Ca(2+) overload and apoptosis by activating PI3K/Akt pathway of primary cultured DRG neurons with excitotoxicity induced by Glu.
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Cell. Mol. Neurobiol. · Oct 2011
Facilitated neurogenesis in the developing hippocampus after intake of theanine, an amino acid in tea leaves, and object recognition memory.
Theanine, γ-glutamylethylamide, is one of the major amino acid components in green tea. In this study, cognitive function and the related mechanism were examined in theanine-administered young rats. Newborn rats were fed theanine through dams, which were fed water containing 0.3% theanine, and then fed water containing 0.3% theanine after weaning. ⋯ Theanine intake significantly increased the number of BrdU-, Ki67-, and DCX-labeled cells in the granule cell layer 6 weeks after the start of theanine administration. This study indicates that 0.3% theanine administration facilitates neurogenesis in the developing hippocampus followed by enhanced recognition memory. Theanine intake may be of benefit to the postnatal development of hippocampal function.
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Cell. Mol. Neurobiol. · May 2011
Elevated S100B and neuron specific enolase levels in patients with migraine-without aura: evidence for neurodegeneration?
Although migraine has mainly been considered as a benign disease, there is cumulative evidence of silent changes in the brain, brainstem, or cerebellum and subtle subclinical cerebellar dysfunction. In this study, in order to investigate a possible neuronal and/or glial damage at the cellular level in migraine, we measured and compared serum levels of S100B which is a protein marker of glial damage or activation, and neuron specific enolase (NSE) which is a marker of neuronal damage, in migraine patients and control subjects. Serum levels of S100B and NSE were measured in blood samples from 41 patients with migraine-without aura taken during a migraine attack (ictal) and in the attack-free period between migraine attacks (interictal) and 35 age- and sex-matched controls. ⋯ On the other hand, serum levels of S100B and NSE in ictal and interictal blood samples did not differ significantly. The findings of increased ictal serum S100B and NSE levels together with increased interictal levels of S100B suggested that migraine might be associated with glial and/or neuronal damage in the brain and a prolonged disruption of blood-brain barrier. Increased interictal serum levels of S100B might point out to an insidious and slow damaging process in migraine patients.
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Cell. Mol. Neurobiol. · Mar 2011
Brain pericytes: emerging concepts and functional roles in brain homeostasis.
Brain pericytes are an important constituent of neurovascular unit. They encircle endothelial cells and contribute to the maturation and stabilization of the capillaries in the brain. ⋯ In addition, brain pericytes are pluripotent and can differentiate into different lineages similar to mesenchymal stem cells. The brain pericytes are revisited as a key player to maintain brain function and repair brain damage.