A Concise Total Synthesis of the Fungal Isoquinoline Alkaloid TMC-120B

Recent reports of antiepileptic activity of the fungal alkaloid TMC-120B have renewed the interest in this natural product. Previous total syntheses of TMC-120B comprise many steps and have low overall yields (11–17 steps, 1.5–2.9% yield). Thus, to access this compound more efficiently, we herein present a concise and significantly improved total synthesis of the natural product. Our short synthesis relies on two key cyclization steps to assemble the central scaffold: isoquinoline formation via an ethynyl-imino cyclization and an intramolecular Friedel-Crafts reaction to form the furanone.

The Effect of Coenzyme Q10 on Liver Injury Induced by Valproic Acid and Its Antiepileptic Activity in Rats

Valproic acid (VPA) has toxic metabolites that can elevate oxidative stress markers, and the hepatotoxicity of VPA has been reported. Coenzyme Q10 (CoQ10) is one of the most widely used antioxidants. The effect of CoQ10 on epileptogenesis and VPA hepatotoxicity were examined. Rats were randomly divided into five groups: the control group received 0.5% methylcellulose by oral gavages daily and saline by intraperitoneal injection three times weekly. The PTZ group received 1% methylcellulose by gavages daily and 30 mg/kg PTZ by intraperitoneal injection three times weekly. The valproic acid group received 500 mg/kg valproic acid by gavage and 30 mg/kg PTZ, as above. The CoQ10 group received 200 mg/kg CoQ10 by gavages daily and 30 mg/kg PTZ, as above. The Valproic acid + CoQ10 group received valproic acid and CoQ10, as above. Results: CoQ10 exhibited anticonvulsant activity and potentiated the anticonvulsant effect of VPA. CoQ10 combined with VPA induced a more significant reduction in oxidative stress and improved the histopathological changes in the brain and liver compared to VPA treatment. In addition, CoQ10 reduced the level of toxic VPA metabolites. These findings suggest that the co-administration of CoQ10 with VPA in epilepsy might have therapeutic potential by increasing antiepileptic activity and reducing the hepatotoxicity of VPA.

Design and evaluation of pharmacological properties of a new 1,3,4-thiadiazolylamide derivative of 2-propylpentanoic acid

Introduction: The use of the pharmacophoric approach is a promising direction for modifying the chemical structure of 2-propylpentanoic (valproic) acid in order to obtain new drugs. Materials and methods: In the experiments on mice, acute toxicity, neurotoxicity, antiepileptic activity and analgesic effect of N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide (valprazolamide) were evaluated. LD50 was determined by probit analysis. Neurotoxicity was determined in a rotarod test and a bar test in mice. The effects of valprazolamide on the exploratory behavior of mice in open field test and in a light/dark transition test were evaluated. Its antiepileptic activity was tested in mice against seizures induced by maximal electroshock, pentylenetetrazole (scPTZ); isoniazid, thiosemicarbazide, pilocarpine, and camphor. The analgesic effect was studied in a hot plate test. Results and discussion: N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide was obtained by introducing pharmacophores into the structure of 2-propylpentanoic acid: a substituted amide group and an electron-donor domain of 1,3,4-thiadiazole. The LD50 value for intraperitoneal administration of a new 2-propylpentanoic acid: derivative to mice was 924.8 mg/kg, and the TD50 value in the rotarod test and the bar test were 456.7 mg/kg and 546.7 mg/kg, respectively. The suppression of orienting responses in the animals was noted when it was administered in neurotoxic doses. Valprazolamide showed the most antiepileptic activity on models of MES, scPTZ and isoniazid antagonism tests. The ED50 values were 138.4 mg/kg, 74.5 mg/kg, and 126.8 mg/kg, respectively. The therapeutic indices for these models of epilepsy were 6.7; 12.4; 7.3, and protective index – 3.3; 6.1 and 3.6, respectively. In the hot plate test, valprazolamide increased the latency period before a defensive response to a thermal stimulus (ED50 165 mg/kg). Conclusion: N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide is a new 1,3,4-thiadiazolylamide derivative of 2-propylpentanoic acid with antiepileptic and analgesic activities, which belongs to the group of low-toxic agents. Graphic abstract N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-propylpentanamide (3D) LD50=924.8 mg/kg (mice, intraperitoneally) TD50=456.7 mg/kg (rotarod, mice, intraperitoneally) ED50=138.4 mg/kg (MES, mice, intraperitoneally) ED50=74.5 mg/kg (scPTZ, mice, intraperitoneally)

Evaluation of Antiepileptic Activity of Flowers of Cocos nucifera L. Against Experimentally Induced Convulsions in Rats

The report used to be planned to analyze the antiepileptic activity of Cocos nucifera flowers against special experimentally induced convulsions in rats. In the present study, antiepileptic activity was assessed by following experimental models. Anti-convulsant in vivo models: Maximal electroshocks (MES) induced models in rats, Pentylenetetrazole (PTZ) induced in rats. Pretreatment of animals with Cocos nucifera flowers extract has reduced by half the general continuance of tonic hind leg extension, the most commonly used endpoint in assessing clonic convulsions. MES provokes repetitive neuronal firing indicates epileptic neurons. MES is the widely accepted model to demonstrate the antiepileptic property of a drug. This property is antagonistic of the plant extract could flow from to blockade of voltage-gated sodium channel or due to effect on NMDA receptors. The Cocos nucifera flowers extract was also demonstrated potential anticonvulsant activity in PTZ induced convulsions and this may be due to its agonistic activity on the GABAA receptor. This is further supported by an elevated level of GABA by the plant extract in the PTZ model. Methanolic extract of Cocos nucifera flowers has shown significant anticonvulsant activity against MES and Pentlylenetetrazole induced convulsion models. This observed activity could also be the referable presence of flavonoids and other phytochemical constituents found in the powerful extract. Keywords: Cocos nucifera, antiepileptic activity, Maximal electroshock, Pentlylenetetrazole, Flavonoids,

Effect of Vortioxetine on Maximal electroshock (MES) induced seizures in Sprague Dawley rats

Aim: To investigate the antiepileptic activity of vortioxetine. Materials and method: Vortioxetine was screened for its antiepileptic activity in Sprague-Dawley rats using maximal electroshock model. 4 groups of rats (each 6 rats) were used. First group was administered distilled water, second group diazepam and the third and fourth groups were given vortioxetine 10mg/kg and 20mg/kg respectively. These drug were given 30 minutes before the animal was subjected to electroshock (150mA, 50Hz for 0.2 seconds). Results: Vortioxetine effectively reduced tonic hind limb extension (THLE) in the rats and the effect was statistically significant compared to the control group. The seizure duration was also significantly lower compared to the control. There was no substantial difference in the duration of seizures and THLE between the diazepam and vortioxetine group. However, the total seizure score of the vortioxetine group was not statistically significant compared to the control group. Conclusion: Vortioxetine has the potential to be clinically useful in treating epilepsy. Further detailed studies using other animal models and in humans are required to prove its efficacy in epilepsy.

Medicinal plants with anticonvulsant activities with emphasis on their mechanisms of action

A large percent of the patients were controlled by the available antiepileptic drugs. The limited efficacy of antiepileptic drugs is still a matter of concern, >30% of patients showed refractory epilepsy and 30-40% suffered from antiepileptic side effects. Many kinds of medicinal plants possessed antiepileptic activity, and many researchers have focused on the efficacy of their crude extracts. This review discussed the medicinal plants with antiepileptic effect focusing on active ingredients and their mode of action.