CXCR5 Regulates Neuronal Polarity Development and Migration in the Embryonic Stage via F-Actin Homeostasis and Results in Epilepsy-Related Behavior / 神经科学通报·英文版

Epilepsy is a common, chronic neurological disorder that has been associated with impaired neurodevelopment and immunity. The chemokine receptor CXCR5 is involved in seizures via an unknown mechanism. Here, we first determined the expression pattern and distribution of the CXCR5 gene in the mouse brain during different stages of development and the brain tissue of patients with epilepsy. Subsequently, we found that the knockdown of CXCR5 increased the susceptibility of mice to pentylenetetrazol- and kainic acid-induced seizures, whereas CXCR5 overexpression had the opposite effect. CXCR5 knockdown in mouse embryos via viral vector electrotransfer negatively influenced the motility and multipolar-to-bipolar transition of migratory neurons. Using a human-derived induced an in vitro multipotential stem cell neurodevelopmental model, we determined that CXCR5 regulates neuronal migration and polarization by stabilizing the actin cytoskeleton during various stages of neurodevelopment. Electrophysiological experiments demonstrated that the knockdown of CXCR5 induced neuronal hyperexcitability, resulting in an increased number of seizures. Finally, our results suggested that CXCR5 deficiency triggers seizure-related electrical activity through a previously unknown mechanism, namely, the disruption of neuronal polarity.

Research progress of cannabidiol in the treatment of epilepsy / 中华神经科杂志

In the treatment of refractory epilepsy,especially in Dravet syndrome and Lennox-Gastaut syndrome,cannabidiol,an anticonvulsant component of marijuana,has shown significant efficacy and safety.However,its mechanism of action and interaction with other drugs are still unclear.For refractory patients who have been treated with a variety of antiepileptic drugs,cannabidiol makes their treatment more promising but also more complicated.This review focuses on the mechanism of cannabidiol and its clinical research progress in the treatment of refractory epilepsy.

Defining drug-resistant epilepsy

Drug resistant epilepsy remains a major clinical challenge. Diverse criteria have been used to defi ne drug resistance by different researchers, making it diffi cult or even impossible to compare the results across different studies. To improve patient care and facilitate clinical research, the International League Against Epilepsy recently proposed a consensus defi nition to defi ne drug resistant epilepsy as failure of adequate trials of two tolerated, appropriately chosen and used antiepileptic drug schedules (whether as monotherapies or in combination) to achieve sustained seizure freedom. This article outlines the framework of the consensus defi nition, explains how to apply it in practice, and discusses the future development in its use.

Association of HLA-B*1502 allele and carbamazepine induced severe adverse cutaneous drug reaction among Asians, a review

Strong association between HLA B*1502 and carbamazepine-induced Steven-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) was demonstrated among Han Chinese in 2004. Studies from Europe showed that the HLA B*1502 is not a universal marker for SJS/TEN, but is ethnicity specific for Asians. Reports across Asia has shown that the prevalence of HLA B*1502 is high among Han Chinese (5-15%), Malays (12-15%), and Thais (8-27%), but low among Japan, Korea, Sri Lanka, and most ethnic groups in India. Other than Han Chinese, the association between HLA B*1502 and carbamazepine-induced SJS-TEN is also seen among the Thais and Malay. There is urgent need for further studies to determine the prevalence of SJS/TEN, and HLA B*1502 in the various ethnic groups in Asia, and its association with carbamazepine-induced SJS-TEN in each of these ethnic groups. In view of the significant morbidity and mortality in SJS-TEN, facilities should be developed to allow for screening of HLA B*1502 before carbamazepine is prescribed to the Hans Chinese, Malays and Thais. For those who experience no adverse cutaneous reaction after 3 months use of carbamazepine, the risk of SJS/TEN is low, and the drugs can be continued.

Epilepsy surgery program in Hong Kong

We reported the experience of epilepsy su�rgery program in 3 centers in Hong Kon��� g They are Prince of Wales Hospital, Queen Elizabeth Hospital and Tuen Mun Hospital. The results of surgery are comparable to best centre elsewhere in the world. Hong Kong has a population of 7 million people with estimated surgical candidates of 3,500����. With e�stimated le�ss than 150 epilep�sy ��sur�geries performed in Hong Kong so far, there is room for further development of epilepsy surgery service in Hong Kong