Abstract:
Background: Fruit extracts of Xylopia aethiopica are used traditionally in the
management of pain disorders including headache and neuralgia. An animal model of
vincristine‑induced sensory neuropathy was developed after repeated intraperitoneal
injection in rats and used in the present work to study the effects of the ethanolic extract of
X. aethiopica (XAE) and its diterpene xylopic acid (XA) in vincristine‑induced neuropathic pain.
Materials and Methods: Vincristine (0.1 mg kg‑1 day‑1) was administered during two cycles
of five consecutive days to induce chemotherapy‑induced neuropathic pain. Static tactile
anti‑allodynic, anti‑hyperalgesic, and cold anti‑allodynic effects of XAE (30‑300 mg kg‑1) and
XA (10‑100 mg kg‑1) were assessed using Von Frey filaments of bending forces of 4, 8,
and 15 g, the Randall‑Selitto paw pressure test, and cold water (4.5°C), respectively.
Results: Administration of vincristine caused the development of allodynia and hyperalgesia
with no significant motor deficit, spontaneous pain, and foot deformity. XAE (30‑300 mg kg‑1)
and XA (10‑100 mg kg‑1) exhibited anti‑hyperalgesic, tactile, and cold anti‑allodynic
properties with XA exhibiting greater potency than XAE. Pregabalin (10‑100 mg kg‑1) used
as control produced similar effect. Conclusion: These findings establish the anti‑allodynic
and anti‑hyperalgesic effects of the ethanolic fruit XAE and its major diterpene XA in
vincristine‑induced neuropathtic pain.
