3-CS3-1
ヒトiPS細胞由来神経細胞を用いた微小電極アレイシステムによる痙攣・てんかん評価法について
Evaluation methods for drug-induced seizure by applying microelectrode array recording to human iPS cell-derived neurons
〇白川誉史1
TakafumiShirakawa1
1アステラス製薬(株)安全性研究所
In the drug development in pharmaceuticals, development of drugs may be discontinued due to the toxicity and clinical side effect, therefore, safety assessment is one of the important factors in drug development. Recently, pre-clinical studies are screening for compounds by the in vitro screening system using human iPS cell-derived cells which are expected to predictively of human clinical. Human iPS Cell Applied Safety Assessment Consortium (CSAHi). CSAHi focuses on hepato-, cardio-, and neuro-toxicities as important toxicity organs which are attributed to the causes of discontinuation of drug development. In neurotoxicity, seizure is an important finding because of high frequency expression in nonclinical. Multi-electrode array (MEA) systems have recently attracted attention as useful for evaluating seizure risk because they can non-invasively measure the electrophysiological activities of neural networks. We are evaluating the electrophysiological responses to several seizure compounds using MEA in cultured hiPSC-derived neurons. It is important to establish an analytical method to detecting seizure-like activities. We have focused the periodicity of synchronized burst firings as one of the effective analytical parameters for detecting seizure risk. We identify the parameter sets that separate the responses between positive and negative compounds using principal component analysis of 10 parameters. The principal component analysis using parameter set focused on periodicity is useful method to detect the seizure risk.
3-CS3-2
医薬品の副作用検出を目指したヒトiPS細胞由来感覚神経細胞のin vitro機能評価法
In vitro functional assay using human iPSC derived sensory neurons for drug side-effects detection
〇鈴木郁郎1
IkurouSuzuki1
1東北工業大学大学院工学研究科電子工学専攻
1Dept. Electronics., Grad. Sch. Eng., Tohoku institute of Tech.
Functional assays using human induced pluripotent stem cell (hiPSC)-derived sensory neurons are expected to predict the drug safety and side effects in human peripheral nervous system. However, evaluation assays in hiPSC-derived sensory neurons has not been established, and electrophysiological response to pain-related molecules are not known. In this study, we aimed to evaluate the physiological responses to pain-related molecules including anti-cancer drugs in cultured hiPSC-derived sensory neurons using high-throughput multi-electrode array (MEA) system. In capsaicin, menthol, and AITC administration, evoked responses depending on TPRV1, TRPM8, and TRPA1 channel were detected, respectively. We found that hiPSC-derived sensory neurons are a heterogeneous cell population that have different responses to temperature and pain molecules, like living body. Cold hypersensitivity responses were also detected in concentration dependent manner of anti-cancer drug oxaliplatin. These results indicated that this MEA evaluation method using human iPSC-derived sensory neurons is effective as a pain-related toxicity in human peripheral nervous system.
3-CS3-3
ゼブラフィッシュを用いた痙攣スクリーニング
Drug-induced seizure liability screening based on a locomotor activity assay in zebrafish
〇山下晃人1、出口二郎1、宮脇出1
AkihitoYamashita1, JiroDeguchi1, IzuruMiyawaki1
1大日本住友製薬(株)前臨床研ユニット
As drug-induced seizures have severe impact on drug development, evaluating seizure induction potential of candidate drugs at the early stages of drug discovery is important. A novel assay system using zebrafish has attracted interest as a high throughput toxicological in vivo assay system, and we have established an experimental method for drug-induced seizure liability on the basis of locomotor activity in zebrafish. Our established experimental method included monitoring locomotor activity at high-speed movement (> 20 mm/sec), extending exposure time or conducting flashlight stimulation (10 Hz) which is a known seizure induction stimulus. The validation study using our methodology was used to assess 52 commercially available drugs, and the prediction rate was approximately 70%. The experimental protocol using zebrafish is considered useful for seizure potential screening during early stages of drug discovery.
3-CS3-4
世界は神経系非臨床試験の充実に向かっている
CNS preclinical studies for drug development are becoming substantial in the world
〇佐藤薫1
KaoruSato1
1国立医薬品食品衛生研究所薬理部第一室
1Lab Neuropharmacol, Div Pharmacol, NIHS
At present, owing to the species differences, we have little options for preclinical studies to predict adverse effects (AEs) in the human CNS. However, as introduced in this symposium, a series of new in vitro experiments have been developed to improve the predictability of CNS AEs.This trend is not limited to Japan inside, but also seen worldwide.Our research project ‘iPSC Non-Clinical Experiments for Nervous System(iNCENS)', aiming at the establishment of the evaluation systems to predict seizure risks of new drugs, is now a committee member of an international think tank, International Life Sciences Institute (ILSI), Health and Environmental Sciences Institute (HESI), NeuTox micro-electrode array (MEA) sub team.Most megapharmas and regulatory agencies are participating in the pilot study to clarify the efficiency of the electrophysiological recordings of MEA.We are providing some promising data recorded from hiPSC-neurons.In this symposium, I will introduce our on-going activities together with the global trends concerning the development of preclinical in vitro evaluation systems to predict CNS AEs.