Localization of alpha-synuclein to mitochondria within midbrain of mice.

The interrelationship between alpha-synuclein (alpha-syn) and mitochondria is not clearly understood. Owing to the lack of the signal peptide and its predominant localization in the cytosol, alpha-syn is generally considered to affect mitochondrial function through some secondary effects. Contrary to this assumption, here, we show that a portion of alpha-syn is present in the membrane of mitochondria in normal dopaminergic neurons. The same profile is also found in other alpha-syn-positive neurons. Thus, binding to the membrane of mitochondria is the physiological nature of alpha-syn and might also contribute to the pathological role of this protein in the mitochondrial dysfunction in Parkinson's disease.

Role of GABA in electro-acupuncture therapy on cerebral ischemia induced by occlusion of the middle cerebral artery in rats.

This study investigated the possible involvement of gamma-aminobutyric acid (GABA) in the therapeutic effect of cerebral ischemia by electro-acupuncture (EA) using the rat model with middle cerebral artery occlusion (MCAO). By immunohistochemistry, the changes of GABA expression level in the primary infarct area and its penumbral regions were examined. The changes in infarct area and survival neuron percentages were also assessed using haematoxylin and eosin stained sections after picrotoxin (PTX) injection, a GABA receptor's antagonist. Our results showed that EA markedly decreased the ischemic damaged areas in the cerebral cortex and hippocampus. Concomitant to this was an up-regulation of GABA immunoexpression in MCAO rats with EA treatment (P < 0.05). Furthermore, injection of PTX in rats subjected to MCAO or MCAO followed by EA treatment increased the infarct area and decreased survival cell percentage significantly when compared with those without PTX injection. In the light of these findings, it is suggested that EA on specific and established acupoints that are commonly used in clinical management of cerebral ischemia may have elicited an up-regulated expression of GABA that would have a neuroprotective effect.

Electro-acupuncture improves epileptic seizures induced by kainic acid in taurine-depletion rats.

Electro-acupuncture (EA) partially inhibited epilepsy with great success. The biological basis underlying EA anti-convulsion remained uncertain, which resulted in limited application and slow improvement of acupuncture. Our previous study indicated that taurine may play an inhibitory role against epilepsy as an inhibitory amino acid in the central nervous system and EA may inhibit epilepsy via up-regulating the expression of taurine transporter to increase the release of taurine. Involvement of taurine in kainic acid (KA)-induced epilepsy and anti-convulsion of EA was further addressed on taurine deficiency animal in the present work. We instituted endogenous taurine-deficiency model by supplementation of beta-alanine (3%) in drinking water for continuous 10 days initially, injected KA into lateral cerebral ventricle to induce epileptic seizure, and performed EA treatment on DU26 "RenZhong" and K "YongQuan" acupoints by an EA apparatus (Model G6805-2) using successive waves with the frequency 64Hz and the current intensity 0.8-1.0 mA for 30 minutes in Sprague-Dawley (SD) rats. Taurine levels markedly decreased in cortex, hippocampus, striatum and cerebellum of rats after beta-alanine administration by fluore-HPLC measurement. EA alleviated epileptic activity in rats at 3.5 h time point after KA injection, whereas beta-alanine-induced taurine depletion rendered rats more susceptible to KA-induced epilepsy. Taurine transporter level increased after EA treatment. These results suggested that taurine participated in epileptogenesis and EA may be related to taurine in controlling epileptic seizure.

Involvement of taurine in penicillin-induced epilepsy and anti-convulsion of acupuncture: a preliminary report.

The potential role of taurine on epilepsy and acupuncture anti-convulsion was addressed in the present study. Epilepsy was induced by micro-injection of penicillin into hippocampus of Wistar rats. Taurine was applied by intraperitioneal (i.p.) injection. Electro-acupuncture (EA) was performed on acupoints of DU 20 "Bai Hui" and DU 16 "Feng Fu" along DU channel. Epileptic grades were evaluated by electro-encephalography (EEG) and behavior score. We featured the dose-response relationship between taurine-treated epilepsy and epilepsy-only subjects, detected the effect of exogenous taurine on epilepsy and acupuncture treatment, and investigated taurine transporter immuno-activity in hippocampus using immunohistochemistry. It was found that: 1), taurine had a significant antiepileptic effect as applied at i.p. 20 mg/kg, 40mg/kg, 80mg/kg, especially at 40mg/kg in the rat model of penicillin-induced seizure. Animals were improved by one to three Racine grades in behavior and in frequency and amplitude of EEG. 2), Exogenous taurine enhanced the anti-convulsive effect of EA. Both behavior and EEG were improved in taurine-treated rats. EA inhibited epilepsy. Exogenous taurine improved epilepsy in a synergistic manner to EA. 3), EA increased the concentration of taurine transporter in hippocampus by comparing EA-treated epilepsy with normal control and penicillin only, or EA-treated plus taurine-treated epilepsy with taurine-treated only epilepsy and penicillin only. The resulting data suggested that taurine may play an inhibitory role against epilepsy as an inhibitory amino acid in the central nervous system and EA may inhibit epilepsy via upregulating the concentration of taurine transporter to increase the release of taurine.

[The protective effect of basic fibroblast growth factor (bFGF) and electroacupuncture on neurons against cerebral ischemia].

Transient cerebral ischemia/reperfusion rat model was adopted, and the method of HE staining, TUNEL staining (TdT-mediated dUTP Nick End Labeling) were used to observe the effect of electroacupuncture (EA) and basic fibroblast growth factor (bFGF) on neuronal death. The results evinced that the combination of EA and bFGF could evidently reduce the neuronal death, including both necrosis and apoptosis, compared with EA or bFGF application alone. It is suggested that bFGF and EA can complement each other and enhance the protective effect following cerebral ischemia.

Expression of interleukin-6 mRNA in ischemic rat brain after electroacupuncture stimulation.

Interleukin-6 (IL-6) is a potent, pleiotropic cytokine that plays a central role in host defense and acute inflammatory responses, exhibiting pro- and anti-inflammatory activities. However, little is known about the effect of acupuncture on IL-6 in inflammatory responses caused by cerebral ischemia-reperfusion. The objective of present study was to investigate the influence of electroacupuncture (EA) on IL-6 mRNA expression in ischemic rat brain, by means of reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. Data showed that EA stimulation significantly upregulated IL-6 mRNA levels in rat cortex and striatum following cerebral ischmia-reperfusion (P<0.05 vs. cerebral ischemia group, respectively), but nothing for sham-EA treatment. The result suggests that EA may partially participate in the regulation of inflammatory processes, and the mechanism of neuroprotective action of EA is implicated in modulation of IL-6 gene expression in cerebral ischemic injury.

Modulation of the gene expression in the protective effects of electroacupuncture against cerebral ischemia: a cDNA microarray study.

In the present study, a cDNA microarray technology was used to analyze the gene expression profile in ischemia and in electroacupuncture (EA)-treated ischemia. A focal cerebral ischemia/reperfusion model on Macaca mulatta was performed with a modified middle cerebral artery occlusion method. Among the nearly 8000 genes, approximately 8% of the total number of genes examined were affected after ischemia/reperfusion injury. Major altered genes were downregulated. In EA-treated monkeys, approximately 10% of the total number of genes examined were affected. Major altered genes were upregulated, including signal transduction-, cell-cycle-, metabolism-, stress response-, DNA repair-related genes. One of the representative upregulated genes encodes insulin-like growth factor-1 (IGF-1) was confirmed using in situ hybridization. Results showed that after ischemia/reperfusion injury, IGF-1 mRNA expression decreased in ipsilateral striatum, whereas increased in ipsilateral hippocampus. No expression changes were observed in cortex. EA treatment could obviously upregulate the IGF-1 mRNA expression in striatum, and further enhance its expression in hippocampus. Therefore, the data presented suggest a possible mediator underlying the mechanisms of anti-ischemic effect of acupuncture. In conclusion, the protective mechanisms of EA against stroke include several related pathways and gene expressions. Microarray analysis may provide a framework for understanding these complicated mechanisms and yield valuable, clinically relevant insights and potentially therapeutic targets of stroke.

[Regulative effect of electroacupuncture on aquaporin-4 in rats with focal cerebral ischemia/reperfusion].

OBJECTIVE: To study the effect of electroacupuncture (EA) on changes of aquaporin-4 (AQP4) expression in rats with cerebral ischemia/reperfusion(CI/R). METHODS: One hundred and seventy male Sprauge-Dawley rats were randomized into control (n = 50), CI/R model (n = 60) and EA (n = 60) groups, and the later 2 groups were further divided into 6 h, 12 h, 24 h, 48 h and 72 h subgroups, with 12 cases in each. CI/R model was established by occlusion of the middle cerebral artery (MCAO). EA (3.85/6.25 Hz, 0.8 - 1.0 mA) was applied to "Shuigou" (GV 26) and "Baihui" (GV 20) for 30 min. Transcardial perfusion was conducted with normal saline + paraformaldehyde in rats of different groups for taking brain tissue samples. The degree of brain edema was detected by cresyl violet stain method, permeability of the blood-brain barrier (BBB) reflected with IgG value in brain tissue was displayed by immunohistochemistry, and AQP4 protein and mRNA expression of corpora striata (CS) were detected by using immunohistochemistry (ABC) and RT-PCR techniques respectively. RESULTS: Twelve hours after CI/R, the hemisphere of brain began to get swelling significantly and the exosmose state of IgG became evidently; compared with the corresponding phases of model group, the swell rates in 24 h, 48 h and 72 h subgroups of EA group were significantly lower (P < 0.05, 0.01), and nearly no IgG immunoreaction positive products were found in different phases of EA group. The expression of AQP4 protein and mRNA increased significantly from 12 h and 24 h on separately in model group, while the expression in EA group was markedly weaker. The ratios of AQP4 mRNA and beta-actin mRNA of CS on the affected side of the brain from 24 h to 72 h of EA group were significantly lower than those of model group (P < 0.05, 0.01). CONCLUSION: EA can reduce the degree of brain edema induced by CI/R and improve the degree of BBB injury, which may be related to its effect in down-regulating AQP4 expression.