Treatment of cholinergic-induced status epilepticus with polytherapy targeting GABA and glutamate receptors.

Despite new antiseizure medications, the development of cholinergic-induced refractory status epilepticus (RSE) continues to be a therapeutic challenge as pharmacoresistance to benzodiazepines and other antiseizure medications quickly develops. Studies conducted by Epilepsia. 2005;46:142 demonstrated that the initiation and maintenance of cholinergic-induced RSE are associated with trafficking and inactivation of gamma-aminobutyric acid A receptors (GABAA R) thought to contribute to the development of benzodiazepine pharmacoresistance. In addition, Dr. Wasterlain's laboratory reported that increased N-methyl-d-aspartate receptors (NMDAR) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAR) contribute to enhanced glutamatergic excitation (Neurobiol Dis. 2013;54:225; Epilepsia. 2013;54:78). Thus, Dr. Wasterlain postulated that targeting both maladaptive responses of reduced inhibition and increased excitation that is associated with cholinergic-induced RSE should improve therapeutic outcome. We currently review studies in several animal models of cholinergic-induced RSE that demonstrate that benzodiazepine monotherapy has reduced efficacy when treatment is delayed and that polytherapy with drugs that include a benzodiazepine (eg midazolam and diazepam) to counter loss of inhibition, concurrent with an NMDA antagonist (eg ketamine) to reduce excitation provide improved efficacy. Improved efficacy with polytherapy against cholinergic-induced seizure is demonstrated by reduction in (1) seizure severity, (2) epileptogenesis, and (3) neurodegeneration compared with monotherapy. Animal models reviewed include pilocarpine-induced seizure in rats, organophosphorus nerve agent (OPNA)-induced seizure in rats, and OPNA-induced seizure in two mouse models: (1) carboxylesterase knockout (Es1-/- ) mice which, similarly to humans, lack plasma carboxylesterase and (2) human acetylcholinesterase knock-in carboxylesterase knockout (KIKO) mice. We also review studies showing that supplementing midazolam and ketamine with a third antiseizure medication (valproate or phenobarbital) that targets a nonbenzodiazepine site rapidly terminates RSE and provides further protection against cholinergic-induced SE. Finally, we review studies on the benefits of simultaneous compared with sequential drug treatments and the clinical implications that lead us to predict improved efficacy of early combination drug therapies. The data generated from seminal rodent studies of efficacious treatment of cholinergic-induced RSE conducted under Dr. Wasterlain's guidance suggest that future clinical trials should treat the inadequate inhibition and temper the excess excitation that characterize RSE and that early combination therapies may provide improved outcome over benzodiazepine monotherapy.

Research on the Material Basis and Mechanism of Kudzu Root in Preventing and Treating Cerebral Ischemia based on Network Pharmacology.

BACKGROUND: It has been shown that Kudzu root has significant pharmacological effects such as improving microcirculation, dilating coronary arteries, and increasing cerebral and coronary blood flow, but its material basis and mechanism of action are not clear. OBJECTIVE: The aim of this study was to investigate the mechanism of action of Kudzu root in the prevention and treatment of cerebral ischemia (CI) through network pharmacology combined with animal experiments. METHODS: The components of kudzu root were screened by using the Chemistry Database, Chinese Academy of Science. Linpinski's five rules were used to perform pharmacophore-like analysis to obtain the active ingredients of Kudzu root. The Swiss Target Prediction Service database was used to predict the potential protein targets of kudzu root components associated with CI. An active ingredient-target network was constructed by using Cytoscape 3.6.0. A rat model of middle cerebral artery occlusion (MCAO) was established, then the main targets and signaling pathways predicted were verified by observing the area of cerebral infarction and Western blot experiments. RESULTS: In total, 84 major active compounds and 34 targets included gerberoside, belonging to the isoflavone class, gallic acid, amino acid class, 4-Methylphenol, phenolic class, and quercetin, and flavonoid class (Flavonoids). The targets covered were proteins related to excitatory amino acids and calcium overload, including Excitatory amino acid transporter 2 (SLC1A2), Glutamate receptor ionotropic, kainate 1 (GRIK1), Glutamate receptor ionotropic, NMDA 1 (GRIN1), Glutamate receptor 2(GRIA2), Calcium/calmodulin-dependent protein kinase II (CaMKII), Neuronal nitric oxide synthase(nNOS). Glutamatergic energy is prominent, and calcium transport across the membrane is central to the network and occupies an important position. CONCLUSION: Kudzu root can significantly reduce neurological damage in rats with CI, and also significantly reduce the rate of cerebral infarction. It is worth noting that Kudzu root can prevent and treat CI by reducing excitatory amino acid toxicity and improving calcium overload.