Anticonvulsant Effect of Uncaria rhynchophylla (Miq) Jack.

Abstract

This study investigated the anticonvulsant effect of Uncaria rhynchophylla (UR) and the physiological mechanisms of its action in rats. A total of 70 male Sprague-Dawley (SD) rats were selected for study. Thirty four of these rats were divided into 5 groups as follows: 1) CONTROL GROUP (n = 6): received intraperitoneal injection (i.p.) of kainic acid (KA, 12 mg/kg); 2) UR1000 group (n = 10), 3) UR500 group (n = 6) 4) UR250 group, received UR 1000, 500, 250 mg/kg i.p. 30 min prior to KA administration, respectively; 5) Contrast group: received carbamazepine 20 mg/kg i.p. 30 min prior to KA administration. Behavior and EEG were monitored from 15 min prior to drug administration to 3 hours after KA administration. The number of wet dog shakes were counted at 10 min intervals throughout the experimental course. The remaining 36 rats were used to measure the lipid peroxide level in the cerebral cortex one hour after KA administration. These rats were divided into 6 groups of 6 rats as follows: 1) Normal group: no treatment was given; 2) CONTROL GROUP: received KA (12 mg/kg) i.p.; 3) UR1000 group, 4) UR500 group, 5) UR250 group, received UR 1000, 500, 250 mg/kg i.p. 30 min prior to KA administration, respectively; 6) Contrast group: received carbamazepine 20 mg/kg i.p. 30 min prior to KA administration. Our results indicated that both UR 1000 and 500 mg/kg decreased the incidence of KA-induced wet dog shakes, no similar effect was observed in the UR 250 mg/kg and carbamazepine 20 mg/kg group. Treatment with UR 1000 mg/kg, 500 mg/kg, or 250 mg/kg and carbamazepine 20 mg/kg decreased KA-induced lipid peroxide level in the cerebral cortex and was dose-dependent. These findings suggest that the anticonvulsant effect of UR possibly results from its suppressive effect on lipid peroxidation in the brain.

Metabolites of Hirsuteine and Hirsutine, the Major Indole Alkaloids of Uncaria rhynchophylla, in Rats

“…1,2) HT and HS were isolated as major active indole alkaloids from the Uncaria species. [7][8][9] To date, however, no studies have been carried out to determine their metabolic fates.…”

Long‐Term Intake of Uncaria rhynchophylla Reduces S100B and RAGE Protein Levels in Kainic Acid‐Induced Epileptic Seizures Rats

“…The administration of the alkaloid fraction of UR in cultured hippocampal neurons alleviates neuronal death and apoptosis-associated genes including c-jun , bax , and p53 [53, 54]. We suggested in our previous studies that UR lowers KA-induced lipid peroxide levels [51] and offers neuroprotection against KA-induced epilepsy by regulating GFAP and S100B [23]. Other studies have reported that brain trauma induces temporal lobe damage and causes temporal lobe epilepsy, hippocampal sclerosis, and neocortical damage [55, 56].…”

“…Each gram of freeze-dried extract contained 1.81 mg of the pure alkaloid component of UR. The dose response for this compound was reported in our previous study [51]. Hence, this effective dose was used for all of the experiments in the current study.…”

Antiepileptic Effect ofUncaria rhynchophyllaandRhynchophyllineInvolved in the Initiation of c-Jun N-Terminal Kinase Phosphorylation of MAPK Signal Pathways in Acute Seizures of Kainic Acid-Treated Rats

“…According to the recording of Bencoogongmu, the UR can treat vertigo and epileptic seizure [9]. Our previous study showed that UR can reduce epileptic seizures [10]. It can also reduce microglial activation, neuronal and inducible nitric oxide synthase immunoreactive cells of the hippocampus in kainic acid (KA)-treated rats, and also acts as a neuroprotector [11].…”