Hydroethanolic Extract of Capparis spinosa Amends Vincristine-Induced Peripheral Neuropathy in Rats

Peripheral neuropathy is a common side effect of chemotherapeutic agents. This study aimed to assess the impact of hydroalcoholic extract from Capparis spinosa fruit on mechanical allodynia and heat hyperalgesia induced by vincristine.

Vincristine (0.1 mg/kg/day, intraperitoneally) was used to induce peripheral neuropathy in rats for 2 weeks. The rats received treatment with the hydroalcoholic extract of Capparis spinosa fruit (100, 200, and 400 mg/kg, orally) or pregabalin (20 mg/kg, orally) for 2 weeks. Assessments of thermal and mechanical hyperalgesia were conducted using the hot plate, open field, footprint, grip strength, and von Frey hair tests. To investigate the roles of opioid and serotonergic pathways in anti-nociceptive and locomotor activities, naloxone (1 mg/kg) and cyproheptadine (5 mg/kg) were administered in conjunction with the extract.

Two weeks post vincristine administration, there was a significant decrease in thermal and mechanical nociceptive thresholds, muscle strength, and locomotor activity in rats compared to untreated groups. In all tests, pregabalin mitigated vincristine’s effects; notably, the Capparis spinosa extract at a dose of 400 mg/kg significantly reduced neuropathic behavioral changes compared to animals that received vincristine. The efficacy of the extract at the 400 mg/kg dose was diminished by naloxone in the von Frey filament test (P < 0.01), hot plate test (P < 0.05), and grip strength test (P < 0.001). Additionally, cyproheptadine reversed the extract’s effect in the grip strength (P < 0.0001) and von Frey filament tests (P < 0.01).

The findings suggest that the hydroalcoholic extract of Capparis spinosa fruit may counteract vincristine-induced neuropathic pain through opioidergic and serotonergic pathways. The extract’s beneficial effects are likely due to its flavonoid and phenolic compound content.