Role of LOX/COX pathways in 3-nitropropionic acid-induced Huntington's Disease-like symptoms in rats: protective effect of licofelone (Publication with Expression of Concern. See vol. 176, pg. 1170, 2019)

BACKGROUND AND PURPOSE Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by a degeneration of striatal neurons. The possible role of COX and lipoxygenase (LOX) pathways has been well-documented in the pathology of several neurodegenerative disorders including HD. Licofelone is a competitive inhibitor of COX-1-and COX-2 and 5-LOX isoenzymes. Therefore, the present study was designed to investigate possible neuroinflammatory and apoptotic mechanisms in the neuroprotective effect of licofelone against 3-nitropropionic acid (3-NP)-induced HD-like symptoms in rats. EXPERIMENTAL APPROACH Rats were administered 3-NP (10 mg.kg(-1)day(-1), i. p.) for 14 days. Licofelone (2.5, 5 and 10 mg.kg(-1), p.o.) was given once a day, 1 h before 3-NP treatment for 14 days. Body weight and behavioural parameters (locomotor and rotarod activity) were assessed on the 1st, 5th, 10th and 15th day post-3-NP administration. Malondialdehyde, nitrite concentration, endogenous antioxidant enzymes (superoxide dismutase and catalase levels), mitochondrial enzyme complexes, pro-inflammatory compounds (TNF-alpha, IL-6, NF-kappa B), PGs (PGE(2) and PGF(2 alpha)) and caspase-3 activity were measured on day 15 in the striatum. KEY RESULTS Systemic 3-NP treatment significantly reduced body weight, locomotor activity, oxidative defence, mitochondrial enzyme complex activities and increased TNF-alpha, IL-6, caspase-3 activity, NF-kappa B and PGE(2) and PGF(2 alpha) levels in the striatum. Licofelone (2.5, 5 and 10 mg.kg(-1)) significantly attenuated the impairment in behavioural, biochemical and mitochondrial, pro-inflammatory and pro-apoptotic markers as compared with vehicle-treated group. CONCLUSIONS AND IMPLICATIONS The results demonstrate the involvement of pro-inflammatory compounds and the apoptotic cascade in the neuroprotective effect of licofelone against 3-NP-induced neurotoxicity.