26S proteasome regulates differentiation of human bone marrow stromal cells into neural-like cells / 中国病理生理杂志

AIM: To investigate the process of human bone marrow stromal cells (hBMSCs) differentiation into neural-like cells and to determine the role of 26S proteasome in neuronal differentiation. METHODS: Purified hBMSCs were treated with β-mercaptoethanol (β-ME) for 1 day and retinoic acid (RA) for 3 days, followed by growth factor (10 μg/L bFGF or 20 μg/L NGF) for another 3 days. Immunofluorescence was performed to detect the expression of nestin (a neural precursor cells marker), Tuj1 (a premature neuronal marker), and neurofilament (NF, a mature neuronal marker) at all stages of induced differentiation. Immunostaining and RT-PCR were used to analyze the expression of 26S proteasome during neuronal differentiation of hBMSCs. To further confirm the role of 26S proteasome in hBMSCs differentiation, cells were treated with β-ME/RA and then followed by protesome inhibitor MG132 and growth factor. Immunostaining was performed to detect NF-positive cells. RESULTS: Quantification results showed that the untreated cells were almost never positive for nestin, Tuj1 and NF. After treated with β-ME/RA, the numbers of nestin-positive cells (34.41%±1.27%) and Tuj1-positive cells (27.79%±1.27%) were increased. Notably, the numbers of NF-positive cells were significantly increased to 56.72%±2.4% after induction with β-ME/RA/GF. Immunofluorescence analysis showed that undifferentiated hBMSCs cells were weakly stained by antibody against 26S proteasome, but the numbers of cells with high-intensity of 26S proteasome were increased after treated with β-ME/RA. The RT-PCR result of 26S proteasome further confirmed that the mRNA level of the cells differentiated by β-ME/RA (1.33), as well as by β-ME/RA/GF (1.77), was significantly increased compared to the undifferentiated cells. Moreover, hBMSCs incubated with protesome inhibitor MG132 significantly decreased the numbers of NF-positive cells (37.59%±1.52%). CONCLUSION: After induction with β-ME/RA/GF, hBMSCs can be differentiated into neural-like cells, which is concomitant with the increase in 26S proteasome expression. Inhibitor of 26S protesome prevents hBMSCs differentiation, suggesting that 26S proteasome may be involved in the differentiation of hBMSCs into neural-like cells.

Effect of Nasal Administration of Compound of Cholera Toxin B Subunit and Nerve Growth Factor on Spatial Learning and Memory Abilities in the Amnesic Mice / 中国康复理论与实践

@#ObjectiveTo explore the effects of the conjugate prepared from the cholera toxin B subunit(CB) and nerve growth factor(NGF) on the spatial learning and memory abilities and cholinergic function.MethodsThe conjugate of CB-NGF was prepared by the improved sodium metaperiodate method and nasally administrated to the β-amyloid protein(Aβ25-35) induced amnesic mice for 7 days with 2 dosage (7-5 μg/d、15 μg/d). Spatial learning and memory abilities were evaluated by Morris water maze and cholinergic function was assessed with the choline acetyl transferase (ChAT) immunohistochemical methods.ResultsMorris water maze test showed that the escape latency in Aβ25-35-treated mice prolonged and the staying time reduced in the crossed first quadrant where the platform had been located, compared with the control mice (P<0-01). In addition, the number of ChAT positive neuron declined in the model mice(P<0-001). CB-NGF nasal administration significantly shortened the escape latency and elevated the staying time and number of ChAT positive neuron(P<0-01).ConclusionCB-NGF treatment can improve the spatial and memory performance which may involve the neuroprotection to cholinergic system.

Pathology and the expression of Bcl- 2 and Bax in spinal cord of guinea pigs in experimental allergic encephalomyelitis / 中国病理生理杂志

AIM: To elucidate the molecular mechanism of apoptosis in inflammatory cells occurring in the central nervous system during experimental allergic encephalomyelitis (EAE), the changes of pathology and the expression of apoptosis-related molecules Bcl-2 and Bax in the spinal cord of guinea pigs in EAE model were observed. METHODS: EAE model was induced in guinea pig. The cervical and lumbosacral enlargement of spinal cord was obmined during the 14 th and 28 th days after modeling. The H & E staining and ABC immunohistochemistry technique were used. RESULTS: HE staining: The lesion in the model was located in the inflammation of small veins, which were surrounded by inflammatory cells. It was specially noticed that inflammatory cells also infiltrated large veins. The lesions in the 28th day were more severe than that in the 14th day. ABC immunohistochemistry staining: The positive expression of Bcl-2 and Bax was obviously increased in the spinal cord of guinea pig with EAE. The number of Bcl-2 positive cells in the 28th day of model group was more than that of the 14th day. The number of Bax positive cells in the 28th day and 14th day of model group did not show obvious difference at un-lesion areas. CONCLUSION: These results suggest that Bcl-2 and Bax may play an important role in EAE.

THE LYMPHATIC SYSTEM OF THE NASOPHARYNX / 解剖学报

The lymphatic vessels and regional nodes of the nasopharynx in 70 foetuses and infant cadavers were studied with the method of injection of the lymphatics of the organ.There is a network of lymphatic capillaries in the mucous membrane of the nasopharynx, which drains into the submucous lymphatics. The latter join together to form a number of efferent ducts.The efferents emerging from the posterior wall of the nasopharynx end in the retropharyngeal lateral and medial nodes, or pass to the posterior aspect of the internal carotid artery and internal jugular vein and end in the upper deep cervical nodes lying deep to the tip of the mastoid.The lymphatics emerging from the lateral wall drain into the nodes right under the base of the skull anterior to the internal carotid artery and internal jugular vein, or descend to the jugulodigastric node, and the upper deep cervical nodes between the beginning point of the lingual artery and the bifurcate point of the common carotid artery.