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Aims: Deep brain stimulation (DBS) of the anterior nucleus of the thalamus, is an effective therapy for patients with drug‐resistant epilepsy, yet, its mechanism of action remains elusive. Adenosine kinase (ADK), a key negative regulator of adenosine, is a potential modulator of epileptogenesis. DBS has been shown to increase adenosine levels, which may suppress seizures via A1 receptors (A1Rs). We investigated whether DBS could halt disease progression and the potential involvement of adenosine mechanisms. Methods: Control group, SE (status epilepticus) group, SE‐DBS group, and SE‐sham‐DBS group were included in this study. One week after a pilocarpine‐induced status epilepticus, rats in the SE‐DBS group were treated with DBS for 4 weeks. The rats were monitored by video‐EEG. ADK and A1Rs were tested with histochemistry and western blot, respectively. Results: Compared with the SE group and SE‐sham‐DBS group, DBS could reduce the frequency of spontaneous recurrent seizures (SRS) and the number of interictal epileptic discharges. The DPCPX, an A1R antagonist, reversed the effect of DBS on interictal epileptic discharges. In addition, DBS inhibited the overexpression of ADK and the downregulation of A1Rs. Conclusion: The findings indicate that DBS can reduce SRS in epileptic rats via inhibition of ADK and activation of A1Rs. A1Rs might be a potential target of DBS for the treatment of epilepsy. [ABSTRACT FROM AUTHOR]

Aims: Mesial temporal lobe epilepsy without hippocampal sclerosis (no‐HS MTLE) refers to those MTLE patients who have neither magnetic resonance imaging (MRI) lesions nor definite pathological evidence of hippocampal sclerosis. They usually have resistance to antiepileptic drugs, difficulties in precise seizure location and poor surgical outcomes. Adenosine is a neuroprotective neuromodulator that acts as a seizure terminator in the brain. The role of adenosine in no‐HS MTLE is still unclear. Further research to explore the aetiology and pathogenesis of no‐HS MTLE may help to find new therapeutic targets. Methods: In surgically resected hippocampal specimens, we examined the maladaptive changes of the adenosine system of patients with no‐HS MTLE. In order to better understand the dysregulation of the adenosine pathway in no‐HS MTLE, we developed a rat model based on the induction of focal cortical lesions through a prenatal freeze injury. Results: We first examined the adenosine system in no‐HS MTLE patients who lack hippocampal neuronal loss and found ectopic expression of the astrocytic adenosine metabolising enzyme adenosine kinase (ADK) in hippocampal pyramidal neurons, as well as downregulation of neuronal A1 receptors (A1Rs) in the hippocampus. In the no‐HS MTLE model rats, the transition of ADK from neuronal expression to an adult pattern of glial expression in the hippocampus was significantly delayed. Conclusions: Ectopic expression of neuronal ADK might be a pathological hallmark of no‐HS MTLE. Maladaptive changes in adenosine metabolism might be a novel target for therapeutic intervention in no‐HS MTLE. [ABSTRACT FROM AUTHOR]

Clausena lansium Lour. Skeels (Rutaceae) is widely distributed in South China and has historically been used as a traditional medicine in local healthcare systems. Although the characteristic components (carbazole alkaloids and coumarins) of C. lansium have been found to possess a wide variety of biological activities, little attention has been paid toward the other components of this plant. In the current study, phytochemical analysis of isolates from a water-soluble stem and leaf extract of C. lansium led to the identification of 12 compounds, including five aromatic glycosides, four sesquiterpene glycosides, two dihydrofuranocoumarin glycosides, and one adenosine. All compounds were isolated for the first time from the genus Clausena, including a new aromatic glycoside (1), a new dihydrofuranocoumarin glycoside (6), and two new sesquiterpene glycosides (8 and 9). The phytochemical structures of the isolates were elucidated using spectroscopic analyses including NMR and MS. The existence of these compounds demonstrates the taxonomic significance of C. lansium in the genus Clausena and suggests that some glycosides from this plant probably play a role in the anticancer activity of C. lansium to some extent. [ABSTRACT FROM AUTHOR]