Ferulic acid ameliorates chronic constriction injury induced painful neuropathy in rats

This study focuses on the evaluation of phenolic compound ferulic acid (FA, 4-hydroxy-3-methoxycinnamic acid) in the chronic constriction injury (CCI) of sciatic nerve induced neuropathy in rats. Thirty-six animals were randomly divided into six groups. Left sciatic nerve was exposed and ligated, animals in the control, standard, and test groups were treated orally with respective drugs for 21 days. Nociceptive thresholds (THERMAL hyperalgesia, mechanical hyperalgesia, and tactile allodynia) were assessed at 0 days and thereafter every 3 days till 3 weeks. Three weeks later, the sciatic nerve tissue homogenate was prepared and subjected for estimation of oxidative markers namely total protein, nitric oxide, lipid peroxidase, interleukins (IL-1 beta and IL-6). Pregabalin (10 mg/kg, p.o.) and ferulic acid (10, 20, 30 mg/kg, p.o.), significantly and dose dependently, decreased all nociceptive thresholds (thermal hyperalgesia, mechanical hyperalgesia, and tactile allodynia) and biochemical markers (total protein, nitric oxide, lipid peroxidase, and interleukins). In conclusion, the anti-hyperalgesic effect of FA in rats receiving CCI might partly be attributed to its anti-oxidant and anti-inflammatory activity and is associated with the maintenance of neuropathic pain and could be useful as an adjuvant to conventional medicines.