Graft of the NT-3 persistent delivery gelatin sponge scaffold promotes axon regeneration, attenuates inflammation, and induces cell migration in rat and canine with spinal cord injury.

Persistent neurotrophic factor delivery is crucial to create a microenvironment for cell survival and nerve regeneration in spinal cord injury (SCI). This study aimed to develop a NT-3/fibroin coated gelatin sponge scaffold (NF-GS) as a novel controlled artificial release therapy for SCI. In vitro, bone marrow-derived mesenchymal stem cells (MSCs) were planted into the NF-GS and release test showed that NF-GS was capable to generate a sustainable NT-3 release up to 28 days. MSCs in NF-GS had high cell activity with excellent cell distribution and phenotype. Then, the NF-GS was transplanted into the injury site of spinal cord of rat and canine in vivo, which exhibited strong biocompatibility during post-transplantation period. Four weeks following transplantation, the concentration of NT-3 was much higher than that in control groups. Cavity areas in the injury/graft site were significantly reduced due to tissue regeneration and axonal extensions associated with myelin sheath through the glial scar into the NF-GS. Additionally, the NF-GS decreased the inflammation by reducing the CD68 positive cells and TNF-α. A striking feature was the occurrence of some cells and myelin-like structure that appeared to traverse the NF-GS. The present results demonstrate that the NF-GS has the property to control the release of NT-3 from the NT-3/fibroin complex thus facilitating regeneration of injured spinal cord.

Identification of marine neuroactive molecules in behaviour-based screens in the larval zebrafish.

High-throughput behavior-based screen in zebrafish is a powerful approach for the discovery of novel neuroactive small molecules for treatment of nervous system diseases such as epilepsy. To identify neuroactive small molecules, we first screened 36 compounds (1-36) derived from marine natural products xyloketals and marine isoprenyl phenyl ether obtained from the mangrove fungus. Compound 1 demonstrated the most potent inhibition on the locomotor activity in larval zebrafish. Compounds 37-42 were further synthesized and their potential anti-epilepsy action was then examined in a PTZ-induced epilepsy model in zebrafish. Compound 1 and compounds 39, 40 and 41 could significantly attenuate PTZ-induced locomotor hyperactivity and elevation of c-fos mRNA in larval zebrafish. Compound 40 showed the most potent inhibitory action against PTZ-induced hyperactivity. The structure-activity analysis showed that the OH group at 12-position played a critical role and the substituents at the 13-position were well tolerated in the inhibitory activity of xyloketal derivatives. Thus, these derivatives may provide some novel drug candidates for the treatment of epilepsy.

Marine compound catunaregin inhibits angiogenesis through the modulation of phosphorylation of akt and eNOS in vivo and in vitro.

Angiogenesis is the formation of blood vessels from pre-existing vasculature. Excessive or uncontrolled angiogenesis is a major contributor to many pathological conditions whereas inhibition of aberrant angiogenesis is beneficial to patients with pathological angiogenesis. Catunaregin is a core of novel marine compound isolated from mangrove associate. The potential anti-angiogenesis of catunaregin was investigated in human umbilical vein endothelial cells (HUVECs) and zebrafish. HUVECs were treated with different concentrations of catunaregin in the presence or absence of VEGF. The angiogenic phenotypes including cell invasion cell migration and tube formation were evaluated following catunaregin treatment in HUVECs. The possible involvement of AKT, eNOS and ERK1/2 in catunaregin-induced anti-angiogenesis was explored using Western blotting. The anti-angiogenesis of catunaregin was further tested in the zebrafish embryo neovascularization and caudal fin regeneration assays. We found that catunaregin dose-dependently inhibited angiogenesis in both HUVECs and zebrafish embryo neovascularization and zebrafish caudal fin regeneration assays. In addition, catunaregin significantly decreased the phosphorylation of Akt and eNOS, but not the phosphorylation of ERK1/2. The present work demonstrates that catunaregin exerts the anti-angiogenic activity at least in part through the regulation of the Akt and eNOS signaling pathways.

Protective effects of puerarin against Aß40-induced vascular dysfunction in zebrafish and human endothelial cells.

Aß40-induced vascular dysfunction has been implicated in the pathogenesis of Alzheimer׳s disease (AD). In the present study, we investigated the possible protective effects of puerarin against Aß40-induced vascular damage and impairment to angiogenesis in transgenic TG (fli1:EGFP) zebrafish and human endothelial cells. Aß40 peptides at 5µM caused an obvious reduction of vessel branches in the subintestinal vein basket, induced NADPH oxidase-derived reactive oxygen species and impaired vascular endothelial growth factor (VEGF)-dependent angiogenesis. Pretreatment with puerarin attenuated Aß40-induced vessel reduction and impairment to angiogenesis in a dose-dependent manner. In addition, Aß40 decreased VEGF-dependent phosphorylation of Akt and eNOS, whereas puerarin treatment attenuated these detrimental effects. Furthermore, the restoration of Aß40-induced-angiogenesis impairment by puerarin was abolished by either the PI3 kinase inhibitor LY294002 (10µM) or eNOS inhibitor L-NAME. The present study suggests that puerarin exerts its protective action probably through reduction of NADPH oxidase-derived reactive oxygen species overproduction and activation of the PI3K/Akt/eNOS pathways.