title: Antihypernociceptive and antioxidant effects of Petersianthus macrocarpus stem bark extracts in rats with complete Freund's adjuvant-induced persistent inflammatory pain.
abstract: Background Petersianthus macrocarpus (P. Beauv.) Liben (Lecythidaceae) is a plant used in Cameroonian folk medicine to cure ailments such as inflammation and pain. Previous work showed that aqueous (AEPM) and methanol (MEPM) extracts from the stem bark of P. macrocarpus possess acute analgesic activities. The present study evaluates whether the same extracts could inhibit persistent hyperalgesia induced by complete Freund's adjuvant (CFA) in rats. Methods Inflammatory pain was induced by intraplantar injection of CFA into the left hind paw of Wistar rats. AEPM and MEPM were administered either acutely or chronically by the oral route at the doses of 100 and 200 mg/kg/day. The mechanical hyperalgesia was tested using an analgesimeter, while the locomotion activity at the end of experiment was evaluated with an open-field device. Nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) contents were assayed in the brain and spinal cord of rats subjected to 14 days chronic treatment. Results AEPM and MEPM at both doses significantly (p<0.001) inhibited the acute and chronic mechanical hyperalgesia induced by CFA. Although not significant, both extracts increased the mobility of CFA-injected animals. AEPM significantly (p<0.01) reduced the level of nitrate at 100 mg/kg, MDA at 200 mg/kg and significantly (p<0.05) increased the SOD in the spinal cord. MEPM significantly increased the SOD content and reduced the MDA concentration in the brain but had no effect on the nitrate. Conclusions AEPM and MEPM exhibit acute and chronic antihyperalgesic activities. In addition, both extracts possess antioxidant properties that might strengthen their chronic antihyperalgesic effects.
authors.forename: Francis Desire Tatsinkou
authors.initials: FDT
authors.lastname: Bomba
authors.forename: Bibiane Aimée
authors.initials: BA
authors.lastname: Wandji
authors.forename: Christian Kuete
authors.initials: CK
authors.lastname: Fofié
authors.forename: Albert
authors.initials: A
authors.lastname: Kamanyi
authors.forename: Télesphore Benoit
authors.initials: TB
authors.lastname: Nguelefack
mesh_terms: D000700:Analgesics / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D002163:Cameroon; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005620:Freund's Adjuvant; D006930:Hyperalgesia / Q000188:drug therapy*; D007249:Inflammation / Q000188:drug therapy; D031381:Lecythidaceae; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D059226:Nociceptive Pain / Q000139:chemically induced / Q000188:drug therapy; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy*; D008517:Phytotherapy; D024301:Plant Bark; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D018547:Plant Stems; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000700:Analgesics; D000975:Antioxidants; D010936:Plant Extracts; D009569:Nitric Oxide; D008315:Malondialdehyde; D005620:Freund's Adjuvant; D013482:Superoxide Dismutase
keywords: Petersianthus macrocarpus; antihypernociception; antioxidant; complete Freund’s adjuvant (CFA); extracts; stem bark