Stimulation of Anterior Thalamic Nuclei Protects Against Seizures and Neuronal Apoptosis in Hippocampal CA3 Region of Kainic Acid-induced Epileptic Rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The antiepileptic effect of the anterior thalamic nuclei (ANT) stimulation has been demonstrated; however, its underlying mechanism remains unclear. The aim of this study was to investigate the effect of chronic ANT stimulation on hippocampal neuron loss and apoptosis.</p><p><b>METHODS</b>Sixty-four rats were divided into four groups: The control group, the kainic acid (KA) group, the sham-deep brain stimulation (DBS) group, and the DBS group. KA was used to induce epilepsy. Seizure count and latency to the first spontaneous seizures were calculated. Nissl staining was used to analyze hippocampal neuronal loss. Polymerase chain reaction and Western blotting were conducted to assess the expression of caspase-3 (Casp3), B-cell lymphoma-2 (Bcl2), and Bcl2-associated X protein (Bax) in the hippocampal CA3 region. One-way analysis of variance was used to determine the differences between the four groups.</p><p><b>RESULTS</b>The latency to the first spontaneous seizures in the DBS group was significantly longer than that in the KA group (27.50 ± 8.05 vs. 16.38 ± 7.25 days, P = 0.0005). The total seizure number in the DBS group was also significantly reduced (DBS vs. KA group: 11.75 ± 6.80 vs. 23.25 ± 7.72, P = 0.0002). Chronic ANT-DBS reduced neuronal loss in the hippocampal CA3 region (DBS vs. KA group: 23.58 ± 6.34 vs. 13.13 ± 4.00, P = 0.0012). After chronic DBS, the relative mRNA expression level of Casp3 was decreased (DBS vs. KA group: 1.18 ± 0.37 vs. 2.09 ± 0.46, P = 0.0003), and the relative mRNA expression level of Bcl2 was increased (DBS vs. KA group: 0.92 ± 0.21 vs. 0.48 ± 0.16, P = 0.0004). The protein expression levels of CASP3 (DBS vs. KA group: 1.25 ± 0.26 vs. 2.49 ± 0.38, P < 0.0001) and BAX (DBS vs. KA group: 1.57 ± 0.49 vs. 2.80 ± 0.63, P = 0.0012) both declined in the DBS group whereas the protein expression level of BCL2 (DBS vs. KA group: 0.78 ± 0.32 vs. 0.36 ± 0.17, P = 0.0086) increased in the DBS group.</p><p><b>CONCLUSIONS</b>This study demonstrated that chronic ANT stimulation could exert a neuroprotective effect on hippocampal neurons. This neuroprotective effect is likely to be mediated by the inhibition of apoptosis in the epileptic hippocampus.</p>

Deep Brain Stimulation of the Subthalamic and Pedunculopontine Nucleus in a Patient with Parkinson's Disease

Deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is a novel therapy developed to treat Parkinson's disease. We report a patient who underwent bilateral DBS of the PPN and subthalamic nucleus (STN). He suffered from freezing of gait (FOG), bradykinesia, rigidity and mild tremors. The patient underwent bilateral DBS of the PPN and STN. We compared the benefits of PPN-DBS and STN-DBS using motor and gait subscores. The PPN-DBS provided modest improvements in the gait disorder and freezing episodes, while the STN-DBS failed to improve the dominant problems. This special case suggests that PPN-DBS may have a unique role in ameliorating the locomotor symptoms and has the potential to provide improvement in FOG.

Effect of anterior nucleus of thalamus stimulation on glucose metabolism in hippocampus of epileptic rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Electrical stimulation of the anterior nucleus of the thalamus (ANT) appears to be effective against seizures. In this study, we investigated changes in glucose metabolism during high-frequency stimulation of ANT in epileptic rats.</p><p><b>METHODS</b>Three groups of rats were used: (1) a stimulation group (n = 12), (2) a sham stimulation group (n = 12) with seizures induced by stereotactic administration of kainic acid (KA), and (3) a control group (n = 12) with sham surgery. Concentric bipolar electrodes were stereotaxically implanted unilaterally in the ANT. High-frequency stimulation was performed in each group except the sham stimulation group. Microdialysis probes were lowered into the CA3 region of the hippocampus unilaterally but bilaterally in the stimulation group. The concentrations of glucose, lactate, and pyruvate in dialysate samples were determined by an ISCUS microdialysis analyzer.</p><p><b>RESULTS</b>The extracellular concentrations of lactate and lactate/pyruvate ratio (LPR) of epileptic rats were significantly higher than in control rats (P = 0.020, P = 0.001; respectively). However, no significant difference in the concentration of glucose and pyruvate was found between these groups (P > 0.05). Electrical stimulation of ANT induced decreases in lactate and LPR in the ipsilateral hippocampus (KA injected) of the stimulation group (P < 0.05), but it did not influence the glucose metabolism in the contralateral hippocampus (P > 0.05).</p><p><b>CONCLUSIONS</b>This study demonstrated that the glycolysis was inhibited in the ipsilateral hippocampus of epileptic rats during electrical ANT stimulation. These findings may provide useful information for better understanding the mechanism of ANT-deep brain stimulation.</p>

Temporal lobe epilepsy with hypothalamic hamartoma: a rare case / 中华医学杂志(英文版)

Refractory gelastic seizure is one of the most common clinical manifestations in patients with hypothalamic hamartoma (HH) and HH is usually regarded as the epileptogenic focus. A young female patient with a small HH and refractory seizures is reported here. However, both the seizure semiology and results of electroencephalogram monitoring indicated the right temporal region was the epileptogenic focus. Thus a standard right anterior temporal lobectomy was performed while the hamartoma preserved. There was a marked improvement in both seizure frequency and quality of life during a 13-month follow-up. The outcome supported the concept that independent epileptogenic focus outside of the hypothalamus might occur in patients with HH.

The neuroprotective effects of lesion and high frequency stimulation of the subthalamic nucleus on the substantia nigra neurons / 中国应用生理学杂志

<p><b>AIM</b>To investigate the neuroprotective effects of lesion and high frequency stimulation(HFS) of the subthalamic nucleus (SIN) on the substantia nigra pars compacta(SNc) neurons and its probable mechanism.</p><p><b>METHODS</b>The PD models were induced by unilateral administration of 6-hydroxydopamine into right substantia nigra in rats. After the high-frequence stimulation to SIN and injection of ibotenic acid to STN on PD rats, the changes of behavior were observed. The substantia nigra neurons were detected by using special-dyeing, TUNEL techniques and immunohistochemistry methods.</p><p><b>RESULTS</b>In the stimulation group, the apoptotic rate was significantly lower than PD model group and lesion group (P < 0.05). Compared with normal rats, model group and lesion one had the similar results of expression of Bcl-2, Bax and their ratio, which were lower expression of Bcl-2, higher expression of Bax and the decrease of their ratio (P < 0.05). In the stimulation group, the expression of Bcl-2 and Bcl-2/Bax were much higher than model group and lesion group. The number of apoptotic neurons of rats in lesion group was smaller than model ones (P < 0.05), but there was no significant difference in expression of Bcl-2, Bax and their ratio (P > 0.05).</p><p><b>CONCLUSION</b>Lesion or HFS of STN have the neuroprotective effects on SNc neurons of PD rats, and HFS has a better long-term effect.</p>