ABSTRACT
Extracts of Feretia apodanthera Del. (Rubiaceae) have been extensively used in traditional Cameroonian medicine to treat a variety of diseases, including some neurological disorders. The present study was aimed to tests the anticonvulsant properties of the aqueous extract and the alkaloid fraction of the stem barks of Feretia apodanthera. The anticonvulsant investigation was carried out against bicuculline-, picrotoxin-, pentylenetetrazol-, Methyl-ß-carboline-3-carboxylate-, N-Methyl-D-aspartate-, 4-aminopyridine-, and maximal electroshock-induced seizures or turning behavior in mice. The aqueous extract protected mice against bicuculline-, picrotoxin-, pentylenetetrazol-, Methyl-ß-carboline-3-carboxylate-, N-methyl-D-aspartate -, 4-aminopyridine- and maximal electroshock-induced seizures or turning behavior. Also, N-Methyl-D-aspartate-, 4-aminopyridine- and maximal electroshock- induced seizures or turning behavior, were significantly antagonized by the alkaloid fraction (80mg/kg) from Feretia apodanthera. The total protection of mice provided by the aqueous extract against convulsions induced by pentylenetetrazol or picrotoxin was anagonized by flumazenil, a specific antagonist of the benzodiazepine site in the GABAA receptor complex. The aqueous extract of Feretia apodanthera (but not the alkaloid fraction) increased the brain GABA content and inhibited the GABA transaminase activity. In conclusion, Feretia apodanthera was revealed possessing anticonvulsant effects in mice, likely via the GABAergic neurotransmission.
Subject(s)
Anticonvulsants/pharmacology , Phytotherapy , Plant Extracts/pharmacology , Rubiaceae , Seizures/drug therapy , 4-Aminobutyrate Transaminase/metabolism , Alkaloids/chemistry , Animals , Anticonvulsants/chemistry , Brain/drug effects , Brain/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , GABA Modulators/pharmacology , Male , Mice , Plant Bark/chemistry , Plant Extracts/chemistry , Receptors, GABA-A/chemistry , Receptors, GABA-A/metabolism , Water/chemistryABSTRACT
Feretia apodanthera Del. (Rubiaceae) is extensively used in ethnomedicine in Cameroon and Nigeria for epilepsy, febrile convulsions, and rheumatic pains and for enhancing cognitive performance. The aim of the present study was to examine the effects of a lyophilized aqueous extract of F. apodanthera on the course of kindling development, kindling-induced learning deficit, oxidative stress markers, and cholinesterase activity in pentylenetetrazole (PTZ)-kindled mice. Pentylenetetrazole, 30mg/kg, induced kindling in mice after 30.00±1.67days. The aqueous extract of F. apodanthera showed dose-dependent antiseizure effects. Feretia apodanthera (150-200mg/kg) significantly increased the latency to myoclonic jerks, clonic seizures, and generalized tonic-clonic seizures. The extract also improved the seizure score and decreased the number of myoclonic jerks. Pentylenetetrazole kindling induced significant oxidative stress and cognitive impairment which were reversed by pretreatment with F. apodanthera in a dose-dependent manner. The significant decrease in cholinesterase activity observed in the PTZ-kindled mice was reversed by pretreatment with the F. apodanthera extract. The results indicated that pretreatment with the aqueous extract of F. apodanthera antagonizes seizures, oxidative stress, and cognitive impairment in PTZ-kindled mice. The aqueous extract of F. apodanthera also showed anxiolytic activities, but the inhibition of memory impairment was not attributed to the anxiolytic activities of the plant. These results thus suggest the potential of F. apodanthera as an adjuvant in epilepsy both to prevent seizures as well as to protect against seizure-induced oxidative stress and memory impairment.