Retinal ganglion cells regenerate long-distance axons through neural activity stimulation and find their way back to the brain

Human central nerve system(CNS)is an extremely complex and delicate structure.While regeneration is possible in some reptiles and fish CNS,the regeneration capacity seems completely lost in adult mammals.Therefore,the classic concept is that once neurons in mammal

Disappearance of unaffected motor cortex activation by repetitive transcranial magnetic stimulation in a patient with cerebral infarct

The ipsilateral motor pathway from the unaffected motor cortex to the affected extremity is one of the motor recovery mechanisms following stroke （Jang, 2011）. Because stroke patients who had shown recovery by this mechanism usually showed poorer motor function, compared with patients who showed recovery by other mechanisms, several researchers have considered this mechanism as a maladaptive plasticity （]ang, 2013）.

Bone morphogenetic protein 2-induced human dental pulp cell differentiation involves p38 mitogen-activated protein kinase-activated canonical WNT pathway

Both bone morphogenetic protein 2（BMP2） and the wingless-type MMTV integration site（WNT）/p-catenin signalling pathway play important roles in odontoblast differentiation and dentinogenesis.Cross-talk between BMP2 and WNT/p-catenin in osteoblast differentiation and bone formation has been identified.However,the roles and mechanisms of the canonical WNT pathway in the regulation of BMP2 in dental pulp injury and repair remain largely unknown.Here,we demonstrate that BMP2 promotes the differentiation of human dental pulp cells（HDPCs） by activating WNT/p-catenin signalling,which is further mediated by p38mitogen-activated protein kinase（MAPK） in vitro.BMP2 stimulation upregulated the expression of p-catenin in HDPCs,which was abolished by SB203580 but not by Noggin or LDN193189.Furthermore,BMP2 enhanced cell differentiation,which was not fully inhibited by Noggin or LDN193189.Instead,SB203580 partially blocked BMP2-induced p-catenin expression and cell differentiation.Taken together,these data suggest a possible mechanism by which the elevation of p-catenin resulting from BMP2 stimulation is mediated by the p38 MAPK pathway,which sheds light on the molecular mechanisms of BMP2-mediated pulp reparative dentin formation.

Stimulating effect of catechin, an active component of Spatholobus suberectus Dunn, on bioactivity of hematopoietic growth factor

Background Hematopoietic growth factor （HGF） is indispensable to hematopoiesis in the body. The proliferation and differentiation of hematopoietic cells must rely on the existence and stimulation of HGF. This study investigated the effect of catechin, an active component extracted from Spatholobus suberectus Dunn （SSD）, on bioactivity of granulocyte-macrophage colony-stimulating activity （GM-CSA）, burst-promoting activity （BPA） and megakaryocyte colony-stimulating activity （MK-CSA） in spleen condition medium （SPCM） of mice to clarify the hematopoietic mechanism of catechin and SSD. Methods Spleen cells of mice were separated and spleen condition medium （SPCM） was prepared from spleen cell culture. Bone marrow cells of mice were separated and cultured in a culture system including 10% （v/v） SPCM （induced by catechin in vivo or ex vivo） for 6 days. Granulocyte-macrophage colony forming units （CFU-GM）, erythrocyte burst-colony-forming units （BFU-E） and megakaryocyte colony-forming units （CFU-Meg） formation were employed to assay the effects of different treatment on the bioactivity of GM-CSA, BPA and MK-CSA in SPCM. Results SPCM induced by 100 mg/L catechin ex vivo could promote the growth of CFU-GM, BFU-E and CFU-Meg, which indicated that catechin could stimulate the production of GM-CSA, BPA and MK-CSA in SPCM. SPCM prepared at the fourth day of spleen cell culture showed the best stimulating activity. The bioactivity of GM-CSA, BPA and MK-CSA in the SPCM prepared after intraperitoneally injecting catechin into mice was also increased. The number of CFU-GM, BFU-E and CFU-Meg gradually increased as the dose of catechin increased and the time of administration prolonged. CFU-GM, BFU-E and CFU-Meg of the high-dose catechin group were significantly higher than those of the control group （P〈0.01） and reached the maximum at the seventh day after administration. Conclusions This study suggests that catechin extracted from the active acetic ether part of Spatholobus suberectus Dunn can regulate hematopoiesis by inducing bioactivity of GM-CSA, BPA and MK-CSA in SPCM of mice. This may be one of the mechanisms for the hematopoietic-supportive effect of catechin and Spatholobus suberectus Dunn.