ABSTRACT
Persicaria lanigera is used traditionally to treat pain. The antinociceptive properties of the hydroethanolic leaf extract of Persicaria lanigera (PLE) were evaluated in rats and mice. Mice were pretreated orally with PLE (30, 100, and 300 mg kg-1) and evaluated for antinociceptive effects in the acetic acid-, glutamate-, and formalin-induced nociception models. Additionally, mechanical hyperalgesia models were used to evaluate PLE's influence on TNF-α- and IL-1ß-induced hyperalgesia in rats. In the acetic acid-induced nociception model, 100 mg kg-1 PLE exhibited the highest antinociceptive activity of 95.13 ± 9.52% at p < 0.0001, followed by the 300 mg kg-1 (85.44 ± 5.75%; p < 0.0001) and then the 30 mg kg-1 (67.95 ± 18.55%; p < 0.01), compared to morphine 3 mg kg-1 i.p. (86.97 ± 9.52; p < 0.0001). PLE (30, 100, and 300 mg kg-1) also showed significant (p < 0.05) antinociceptive effect in phase two of the formalin-induced nociception with % inhibitions of 66.88 ± 12.17, 75.12 ± 9.01, and 89.12 ± 4.32%, respectively, compared to 3 mg/kg morphine (97.09 ± 2.84%). Similarly, PLE (30, 100, and 300 mg kg-1) significantly reduced pain in the glutamate-induced nociception model with % inhibitions of 79.28 ± 8.17, 90.54 ± 5.64, and 96.49 ± 1.43%, respectively, whereas ketamine (5 mg/kg i.p.) reduced nociception to be 59.94 ± 18.14%. All doses of PLE significantly reduced nociceptive scores in TNF-α- and IL-1ß-induced mechanical hyperalgesia (p < 0.01). Similarly, PLE significantly inhibited bradykinin-induced nociception. The hydroethanolic extract of Persicaria lanigera has antinociceptive effects; this is the first scientific report providing evidence to validate its traditional use for the management of pain.
ABSTRACT
Paullinia pinnata L. (Sapindaceae) is an endemic West African plant that is extensively used in traditional medicine to treat various diseases. Previous phytochemical analysis by various groups led to the isolation of several novel lupene-based triterpenene derivatives along with other classes of compounds. As part of our continued phytochemical studies on the roots of this plant, we have now identified yet another novel triterpene, 6a-(3'-methoxy-4'-hydroxybenzoyl)-lup-20(29)-ene-3-one. The identification of the compound through comprehensive spectroscopic studies is discussed.
Subject(s)
Paullinia/chemistry , Plant Roots/chemistry , Triterpenes/chemistry , Molecular StructureABSTRACT
BACKGROUND: Hoslundia opposita Vahl. (Lamiaceae), a common local shrub in Ghana, is traditionally known not only for its pharmacological benefits but also for its insecticidal properties. Its acaricidal property, however, has not been investigated. OBJECTIVE: To test the acaricidal effects of the crude extract and fractions of H. opposita leaves as well as to isolate and characterize the acaricidal principles. MATERIALS AND METHODS: The crude methanolic extract, pet. ether, ethyl acetate and aqueous fractions of the leaves of H. opposita were tested against the larvae of the cattle tick, Amblyomma variegatum, using the Larval Packet Test. A bioassay-guided isolation was carried out to identify the acaricidal principle obtained from the ethyl acetate fraction. RESULTS: The active principle was characterised as ursolic acid, a triterpene previously isolated from the leaves of the same plant. The extract and fractions were less potent than the control, malathion (LC(50) 1.14 × 10(-4) mg/ml). Among the plant samples however the crude methanolic extract exhibited the highest effect against the larvae (LC(50) 5.74 × 10(-2) mg/ml), followed by the ethyl acetate fraction (LC(50) 8.10 × 10(-2) mg/ml). Ursolic acid, pet. ether and aqueous fractions however showed weak acaricidal effects with LC(50) values of 1.13 mg/ml, 8.96 × 10(-1) mg/ml and 1.44 mg/ml, respectively. CONCLUSION: Ursolic acid was not as potent as the crude methanolic extract and the ethyl acetate fraction from which it was isolated. The overall acaricidal effect of H. opposita may have been due to synergy with other principles having acaricidal properties.
