Analgesic and Anti-Inflammatory Activities of Herranone, Spinasterol and Crude Extract of Pachystela msolo in Rat and Mice

Ache Roland N¹, Keugni Brice A², Fotio Lambou A³, Dimo Théophile^2*, Samuel Owusu Y⁴, and Ngadjui Tchaleu B^1
1Department of Organic Chemistry, University of Yaounde I, Cameroon. PO. Box 812.
²Department of Animal Biology and Physiology, University of Yaounde I, Cameroon. PO. Box 812.
³Department of Zoology and Animal Physiology, University of Buea, Cameroon. PO. Box 63.
⁴Department of Chemistry, University of Botswana, Gaborone. Private Bag 00704, Gaborone.

A B S T R A C T
Pachystalamsolo Engler is a plant used in traditional medicines to treat various devices. The present study aims to evaluate herranone, spinasterol and the CH₂Cl₂-MeOH extract of Pachystela msolo for their analgesic and anti-inflammatory activities. Spectroscopic data were used to characterize the isolates from the extract. The analgesic activity was assayed using acetic-acid induced writhing response and formalin test in mice. Anti-inflammatory activities were accessed using model of dextran and carrageenan induced paw oedema in rats. In the study of the analgesic effect, the extract (50, 100, or 200 mg/kg; p.o), herranone and spinasterol (1 or 2 mg/kg; i.p) significantly (p < 0.001, p < 0.01) reduced acetic acid-induced writhing response in mice. In vivo anti-inflammatory activities of the extract, herranone, spinasterol, and the co-administered product (1 mg/kg each; i.p) showed significant (p < 0.01) reduction of formalin-induced paw oedema in mice. Statistically the extract (200 mg/kg) and the co-administered product significantly (p < 0.01) decreased dextran-induced paw oedema in rats. The extract (200 mg/kg) also showed significant (p <0.01) reduction of carrageen an-induced paw oedema in rats for 6 hours. To conclude, the tested products and the extract exerted analgesic and anti-inflammatory activities, which may be due to inhibition of cyclooxygenase, serotonin, histamine, and prostaglandins. The investigation validates the folkloric usage of Pachystela msolo as phytomedicine in the treatment of pain and the identified constituents could serve as useful tool for standardization.
Keywords: Pachystela msolo, herranone, spinasterol, analgesic, anti-inflammatory.