Tau, a primary component of microtubule-associated protein, promotes microtubule assembly and/or disassembly and maintains the stability of the microtubule structure. Although the importance of tau in neurodegenerativ...Tau, a primary component of microtubule-associated protein, promotes microtubule assembly and/or disassembly and maintains the stability of the microtubule structure. Although the importance of tau in neurodegenerative diseases has been well demonstrated, wheth- er tau is involved in peripheral nerve regeneration remains unknown. In the current study, we obtained sciatic nerve tissue from adult rats 0, 1, 4, 7, and 14 days after sciatic nerve crush and examined tau mRNA and protein expression levels and the location of tau in the sciatic nerve following peripheral nerve injury. The results from our quantitative reverse transcription polymerase chain reaction analysis showed that compared with the uninjured control sciatic nerve, mRNA expression levels for both tau and tau tubulin kinase 1, a serine/ threonine kinase that regulates tau phosphorylation, were decreased following peripheral nerve injury. Our western blot assay results suggested that the protein expression levels of tau and phosphorylated tau initially decreased 1 day post nerve injury but then gradually increased. The results of our immunohistochemical labeling showed that the location of tau protein was not altered by nerve injury. Thus, these results showed that the expression of tau was changed following sciatic nerve crush, suggesting that tau may be involved in periph- eral nerve repair and regeneration.展开更多
Aim To study the improvement of docosahexaenoic Acid-phosphatidylcholine （DHA-PC） on the cogni- tive deficits of AD rats induced by Aβ25_35, and investigate molecular mechanism of DHA-PC. Methods 1. fifty healthy w...Aim To study the improvement of docosahexaenoic Acid-phosphatidylcholine （DHA-PC） on the cogni- tive deficits of AD rats induced by Aβ25_35, and investigate molecular mechanism of DHA-PC. Methods 1. fifty healthy wistar rats of SPF level, weighing 250 -0 300 g were randomly divided into control group, AD group, done- pezil group, DHA-PC treated group, DHA group. Each group had 10 rats. Aβ25_35 was injected into hippocampus CA1 area of the AD group rats and drug treated group rats. The same volume of Normal saline was injected in the same area of sham group rats, the control group deal with nothing. All the groups were tested with Morris water maze after operation to test whether AD models. Both DHA-PC treated group and DHA treated group were given by oral administration of corresponding drugs. The AD group and sham group were given by oral administration of nor- mal saline, the control group were fed with normal food. All the groups were treated for 30 days. All the groups were tested with Morris water maze on day 25 after administration. We determined the phosphorylated tau protein of Ser396 site with Western Blot and determined the Superoxide dismutase （SOD）. Results The water maze test was performed： The latency period of AD group was increased compared with the sham group （P 〈 0.05）. The DHA- PC group was spent less time to find the platform compared with the AD group （P 〈 0.05）. DHA-PC treated groups used more linear and tendency modes than AD group. In the probe trial, the AD group spent less time in the target area compared with sham group （P 〈0.01 ） , and the DHA-PC group spent more time in the target area compared with AD group （P 〈 0.05 ）. The results of Western blot are as follows ： DHA-PC reduced the phosphoryl- ated tau protein of Ser396 site expression in cortex （P 〈 0.01 ）. The results of SOD in cortex were increased in DHA-PC treated groups than AD groups （P 〈0.01）. Conclusion DHA-PC can improve the cognitive deficits of AD rats, improve the abnormalities and decreased the level of the phosphorylated Ser396 tau protein of AD rats in cortex. DHA-PC can also improve the cognitive deficits of AD rats by increased SOD.展开更多
基金supported by the National Natural Science Foundation of China,No.81130080,31300942the National Key Basic Research Program of China(973 Program)+5 种基金No.2014CB542202the Natural Science Foundation of Jiangsu Province,China,No.BK20150409the Natural Science Foundation of Jiangsu Higher Education Institutions of China,No.15KJB180013the Scientific Research Foundation of Nantong University of China,No.14R29the Natural Science Foundation of Nantong City in China,No.MS12015043the Priority Academic Program Development of Jiangsu Higher Education Institutions of China
文摘Tau, a primary component of microtubule-associated protein, promotes microtubule assembly and/or disassembly and maintains the stability of the microtubule structure. Although the importance of tau in neurodegenerative diseases has been well demonstrated, wheth- er tau is involved in peripheral nerve regeneration remains unknown. In the current study, we obtained sciatic nerve tissue from adult rats 0, 1, 4, 7, and 14 days after sciatic nerve crush and examined tau mRNA and protein expression levels and the location of tau in the sciatic nerve following peripheral nerve injury. The results from our quantitative reverse transcription polymerase chain reaction analysis showed that compared with the uninjured control sciatic nerve, mRNA expression levels for both tau and tau tubulin kinase 1, a serine/ threonine kinase that regulates tau phosphorylation, were decreased following peripheral nerve injury. Our western blot assay results suggested that the protein expression levels of tau and phosphorylated tau initially decreased 1 day post nerve injury but then gradually increased. The results of our immunohistochemical labeling showed that the location of tau protein was not altered by nerve injury. Thus, these results showed that the expression of tau was changed following sciatic nerve crush, suggesting that tau may be involved in periph- eral nerve repair and regeneration.
文摘Aim To study the improvement of docosahexaenoic Acid-phosphatidylcholine （DHA-PC） on the cogni- tive deficits of AD rats induced by Aβ25_35, and investigate molecular mechanism of DHA-PC. Methods 1. fifty healthy wistar rats of SPF level, weighing 250 -0 300 g were randomly divided into control group, AD group, done- pezil group, DHA-PC treated group, DHA group. Each group had 10 rats. Aβ25_35 was injected into hippocampus CA1 area of the AD group rats and drug treated group rats. The same volume of Normal saline was injected in the same area of sham group rats, the control group deal with nothing. All the groups were tested with Morris water maze after operation to test whether AD models. Both DHA-PC treated group and DHA treated group were given by oral administration of corresponding drugs. The AD group and sham group were given by oral administration of nor- mal saline, the control group were fed with normal food. All the groups were treated for 30 days. All the groups were tested with Morris water maze on day 25 after administration. We determined the phosphorylated tau protein of Ser396 site with Western Blot and determined the Superoxide dismutase （SOD）. Results The water maze test was performed： The latency period of AD group was increased compared with the sham group （P 〈 0.05）. The DHA- PC group was spent less time to find the platform compared with the AD group （P 〈 0.05）. DHA-PC treated groups used more linear and tendency modes than AD group. In the probe trial, the AD group spent less time in the target area compared with sham group （P 〈0.01 ） , and the DHA-PC group spent more time in the target area compared with AD group （P 〈 0.05 ）. The results of Western blot are as follows ： DHA-PC reduced the phosphoryl- ated tau protein of Ser396 site expression in cortex （P 〈 0.01 ）. The results of SOD in cortex were increased in DHA-PC treated groups than AD groups （P 〈0.01）. Conclusion DHA-PC can improve the cognitive deficits of AD rats, improve the abnormalities and decreased the level of the phosphorylated Ser396 tau protein of AD rats in cortex. DHA-PC can also improve the cognitive deficits of AD rats by increased SOD.
