The Research Of MTOR And FKBP38in Thelumbar Spinal Cord Of SOD1-G93A Transgenic Mice

Objective: Amyotrophic lateral sclerosis(ALS) is a neurodegenerativedisease that is characterized by the sleteciveiy lose of motor neurons (MNs).Muscle weakness amyotrophy is the Clinical manifestation of it.Respiratorymuscle is the final result which threatens the life. Once dignosed, people sufferfrom it will die within3to5years. At present,several mechanisms have beenhotly discussed including heredity excitotoxicityoxidative stress the abnormalaggregation of neurofilament the deficiency of neurotrophic factors thedisfunction of mitochondrial autoimmunity apoptosisand deficiency ofautophagy and so on. Recently, the abnormal function of autophagy has been ahot area. mTOR(mammalian target of rapamycin),is a regulator of cell growthand metabolism. The regulating of cell process including the translation ofmRNA, the ribosome biogenesis, autophagy and the metabolism. Afterrecepting and integrating the signal form the external environment, mTORestablish relevant regulation to downstream. MTOR is the critical regulator ofautophagy,and the signal routing of autophagy is closed under the conditionof increased levels of growth factor and abundant nurtion according to it,bythis way, autophagy is inhibited.rapamycin, the inhibitor of mTOR, was usedas a kind of immunosuppressant at first. According to the study, rapamycinactivate autophagy by inhibiting mTOR. Under the physiological conditions,the activity of mTOR is regulated by Rheb, a Ras-like small GTPase, Rheb, apositive regulator of mTOR, a central regulator of cell growth that controls awide spectrum of cellular processes by integrating nutrient and growth factorsignals. According to research, Rheb activates mTOR by antagonizing itsendogenous inhibitor, FKBP38is a member of the family of FK506-bindingproteins, it reveals strong neuroprotection effect and regeneration, indicatingthe ability of regulating the survival and the stability of the cell. Under the grow factor strvation and the amino acid deprivation, FKBP38interracts withmTOR and downregulates the activity of it. When the grow factor and aminoacid recoverd, Rheb interacts with FKBP38and prevents its association withmTORC1, which frees mTOR1for activation.At present, the SOD1-G93A transgenic mice are one of the most idealALS models. According to observe, the amount of mTOR and FKBP38, therelationship between them are explored, the significance of it were purposed,which offer the prove to the futher study of ALS.Methods: SOD1G93A transgenic mice were used as the experimentalanimals. The100days’ littermate controls served as control group. There werefour groups: control group，Pre-symptomatic group, onset group and endinggroup. Each group included eight mice. After10%hydration aldehydes(350mg/kg body weight) intraperitoneal injection anesthesia, decapitated,extracted the lumbar spinal cord of mice immediately, and they were frozen inliquid nitrogen and stored at-80centigrade, fixated tissues via heart perfusionby4%paraformaldehyde, dissected lumbar spinal cord of mice and fixatedthem in4%paraformaldehyde. Using immunocytochemistry, Western blot todetect the morphology, the protein expression of FKBP38and mTOR.Results:1The changes of mTOR in the lumbar spinal cord of SOD1-G93A transgenicmouse: according to Western Blot, Compared with WT group, the proteinlevels of mTOR were remarkably reduced as the illness processes. Accordingto the immunohistochemistry, the neuron in the lumbar spinal cord ofSOD1-G93A transgenic mouse were remarkably reduced, compared with theWT group. The immunocompetence in the neuron were reduced. And the thedifference was statistically significant.2The changes of FKBP38in the lumbar spinal cord of SOD1-G93Atransgenic mouse: according to Western Blot, compared with WT group, theprotein levels of FKBP38were remarkably increased as the illness processes.According to the immunohistochemistry, the immunocompetence of FKBP38in the lumbar spinal cord of SOD1-G93A transgenic mouse were remarkably increased, compared with the WT group. And the difference was statisticallysignificant.Conclusions: According to the observation of anterior horn cell oflumbar spinal cord of SOD1-G93A transgenic mouse, mTOR was reduced asthe illness processes, whereas FKBP38was increased, from which, weconclude that under the cooperation of the increase of FKBP38and the growfactor deprivation and amino acid starvation, the function of mTOR wasinhibited, which influenced the physiological activity of the organism.