ABSTRACT
Ursolic acid (UA; 3b-hydroxy-12-urs-12-en-28-oic acid), a natural pentacyclic triterpenoid carboxylic acid, has been known to possess potent anti-inflammatory, antioxidant, and antinociceptive effects in various animal models. Therefore, this study was designed to investigate the antihyperalgesic, anti-inflammatory, and antioxidant effects of UA at 5, 10, and 20 mg/kg of doses via per os (p.o.) route for 14 days in chronic constriction injury (CCI)-induced neuropathic pain in rats. Pain behavior in rats was evaluated before and after UA administration via mechanical and heat hyperalgesia. CCI caused significant increase in levels of pro-inflammatory cytokines and oxido-nitrosative stress. In addition, significant increase in myeloperoxidase, malondialdehyde, protein carbonyl, nitric oxide (NO), and total oxidant status (TOS) levels in sciatic nerve and spinal cord concomitant with mechanical and heat hyperalgesia is also noted for CCI-induced neuropathic pain. Administration of UA significantly reduced the increased levels of pro-inflammatory cytokines and TOS. Further, reduced glutathione is also restored by UA. UA also showed in vitro NO and superoxide radical scavenging activity. UA has a potential in attenuating neuropathic pain behavior in CCI model which may possibly be attributed to its anti-inflammatory and antioxidant properties.
Subject(s)
Neuralgia/drug therapy , Triterpenes/pharmacology , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Constriction , Cytokines/metabolism , Disease Models, Animal , Hyperalgesia/drug therapy , Hyperalgesia/metabolism , Inflammation/drug therapy , Inflammation/metabolism , Male , Malondialdehyde/metabolism , Neuralgia/metabolism , Nitric Oxide/metabolism , Oxidative Stress/drug effects , Peroxidase/metabolism , Protein Carbonylation/drug effects , Rats , Sciatic Nerve/drug effects , Sciatic Nerve/metabolism , Spinal Cord/drug effects , Spinal Cord/metabolism , Superoxides/metabolism , Ursolic AcidABSTRACT
BACKGROUND: Sepsis commonly progresses to acute lung injury and is associated with high morbidity and mortality. Septic acute lung injury is characterized by severe oxidative stress response, remained refractory to present therapies, and new therapies need to be developed to improve further clinical outcomes. We determined the effect of betulinic acid (BA) on oxidative lung injury in mice using cecal ligation and puncture (CLP) model. MATERIALS AND METHODS: Five groups of mice (six in each group) received three pretreatments at 24-h interval before surgery. Surgery was done 1 h after last dosing. Sham and CLP control group mice received vehicle. BA was administered to other three groups of mice at 3, 10, and 30 mg/kg dose. Lung and plasma samples were collected for analysis by sacrificing the mice at 18 h of surgery. RESULTS: Compared with sham, CLP significantly increased total protein, nitrite, malondialdehyde, isoprostane, superoxide, protein carbonyl, oxidative stress index, inducible nitric oxide synthase protein, and histopathologic changes and reduced the superoxide dismutase, catalase activity, and total thiol levels in lungs and plasma, which were restored by BA pretreatment. CONCLUSIONS: BA pretreatment decreased the levels of oxidants, increased the levels of antioxidants in lungs and plasma thereby reducing the oxidative lung injury in CLP mice. Additionally, BA was found to scavenge the superoxide and nitric oxide radical in vitro. Thus, BA is suggested to be effective in treatment of oxidative lung injury in sepsis.
