ABSTRACT
In this study, we investigated the effect of an antibody against E3 ubiquitin ligase seven in absentia homolog 1 (SIAH-1) in PC12 cells. 1-Methyl-4-phenylpyridinium (MPP(+)) treatment increased α-synuclein, E1 and SIAH-1 protein levels in PC12 cells, and it reduced cell viability; however, there was no significant change in light chain 3 expression. Treatment with an SIAH-1 antibody decreased mRNA expression levels of α-synuclein, light chain 3 and SIAH-1, but increased E1 mRNA expression. It also increased cell viability. Combined treatment with MPP(+) and rapamycin reduced SIAH-1 and α-synuclein levels. Treatment with SIAH-1 antibody alone diminished α-synuclein immunoreactivity in PC12 cells, and reduced the colocalization of α-synuclein and light chain 3. These findings suggest that the SIAH-1 antibody reduces the monoubiquitination and aggregation of α-synuclein, promoting its degradation by the ubiquitin-proteasome pathway. Consequently, SIAH-1 may be a potential new therapeutic target for Parkinson's disease.
ABSTRACT
Brainstem auditory evoked potentials (BAEPs) have been used as a valuable neurophysiologic index of neuronal dysfunction in the level of the brainstem. BAEPs are also useful in subdividing evoked potentials into normal, slight, or pronounced in patients with vertebrobasilar insufficiency. We investigated the changes of BAEP after vertebrobasilar artery ischemia in rabbits and its significance in clinical work. A brainstem ischemic model was made by unilateral extracranial occlusion of vertebral artery to monitor BAEPs at 0, 10, 20, 30, 40, 50, and 60 min after occlusion. We found that peak latencies (PL) of I, III, and most notably V were gradually extended. In addition, we observed a significant (P < 0.05) delay of interpeak latencies (IPL) of waves IIII, IIIV, and IV after occlusion. This delay became more significant in IPL IV 60 min after occlusion. Our results also demonstrate that the amplitude of I and V had no obvious change (P < 0.05). In the rabbit with bilateral extracranial occlusion of vertebral artery, BAEP waveforms disappeared 10 min after occlusion. Our results showed that vertebrobasilar insufficiency caused brainstem ischemia, which induced BAEP abnormity. Taken together, our findings suggest that BAEP has important significance for the clinical diagnosis of vertebrobasilar insufficiency. Therefore, early detection of neuronal change after transient cerebral ischemia is important in initiating treatment within the therapeutic window.
Subject(s)
Early Diagnosis , Evoked Potentials, Auditory, Brain Stem , Vertebrobasilar Insufficiency/diagnosis , Vertebrobasilar Insufficiency/physiopathology , Animals , RabbitsABSTRACT
OBJECTIVE: To establish a method to identify the different origins of herba Evodia rutaecarpa by IR and provide a new technique for their identification and quality evaluation. METHODS: The herba materials were extracted by chloroform and absolute alcohol, the powder and the extracts of Evodia rutaecarpa were mixed and pelleted with KBr. The slides were detected within 4000 - 400 cm(-1) by FIR spectrophotometry. The Difference of samples was studied. RESULTS: The infrared spectrums of Evodia rutaecarpa extracted by chloroform were obviously different. CONCLUSION: The method can be used to identify and appraise the different origins of herba Evodia rutaecarpa.
