Background: Memory deficit is a common cognitive comorbid in patients with neuropathic pain that need better treatment. Recent research revealed that nanocurcumin has an antinociceptive action and a protective effect against memory disorders, suggesting its possible effectiveness for the treatment of neuropathic pain and its comorbidity.
Methods: Adult male albino Wistar rats (n = 32) were randomly divided into four experimental groups: CCI+ nanocurcumin, CCI + vehicle, sham + nanocurcumin, and sham + vehicle. Neuropathic pain induced by a chronic constriction injury of the sciatic nerve. Nanocurcumin or vehicle was injected intraperitoneally for 10 days. Behavioral assessment achieved to evaluate pain threshold in the von Frey test and radiant heat test, also spatial learning and memory examined by the Morris water maze (MWM) test. To explore the possible relation, IL-1β, and TNF-α levels of the hippocampus measured by enzyme-linked immunosorbent assay (ELISA).
Results: Our data showed that CCI caused neuropathic pain-related behaviors and spatial learning and memory disorders in rats. Chronic treatment with nanocurcumin significantly increased pain threshold (P < 0.001; F = 27.63, F = 20.58), improved spatial memory (P < 0.01; F = 47.37), and decreased the hippocampal levels of IL-1β (P < 0.001; F = 33.57) and TNF-α (P < 0.01; F = 7.25) in CCI rats.
Conclusion: Chronic nanocurcumin can ameliorate pain-related behavior, improve spatial learning and memory deficits, and is associated with the reduction of IL-1β and TNF-α levels in the hippocampus in CCI rats. Nanocurcumin may be potentially providing a therapeutic alternative for the treatment of neuropathic pain and its memory impairment comorbidity.
Keywords: IL-1β,TNF-α; Nanocurcumin; Neuropathic pain; Spatial memory, Hippocampus.