In-vivo effects of nociceptin and its structural analogue [Orn9] nociceptin on the antioxidant status of rat blood and liver after carrageenan-induced paw inflammation

The Effect of Prickly Pear, Pumpkin, and Linseed Oils on Biological Mediators of Acute Inflammation and Oxidative Stress Markers

Medicinal plants have been used as a source of effective and safe alternative therapeutic agents for various ailments including inflammation. In fact, the aim of this study is to assess the topical anti-inflammatory and antioxidative potential effects of Cucurbita pepo (pumpkin), Linum usitatissimum (linseed), and Opuntia ficus indica (prickly pear) oils on acute inflammation using carrageenan-induced paw edema model. The study was conducted on 36 rats splitted in 6 groups: a normal control group and 5 carrageenan-treated groups (1%), each treated with either a normal saline, the reference drug (“Inflocine®” 2 mg/paw), pumpkin, linseed, or prickly pear oils (25 μl/paw). The response to these treatments was mainly assessed by the measuring of edema paw size, hematological and biochemical analysis, oxidative stress testing, and histological study. All the studied seed oils especially prickly pear oil proved to be efficient in treating acute inflammation. The oil-treated groups revealed a significant (p < 0.05) decrease in the clinical signs of inflammation, hematological parameters (white blood cells and platelets), concentrations of CRP and fibrinogen, and congestion compared to the normal saline-treated group. The results also showed that the tested oils, endowed with a radical scavenging ability, could significantly increase the activities of SOD, CAT, and GPx in carrageenan-treated skin by reducing the lipid peroxidation and protein oxidation (TBARS, AOPP). The anti-inflammatory effect of the tested oils was closely related to both their antioxidant properties as well as their bioactive compounds (polyunsaturated fatty acids, vitamin E, and phytosterols). For the first time, the findings of the current study highlight the “in vivo” anti-inflammatory property of pumpkin, linseed, and prickly pear oils on carrageenan-induced acute inflammation by regulating inflammatory mediators and oxidative stress markers.

Chemical Composition and Antioxidant, Analgesic, and Anti-Inflammatory Effects of Methanolic Extract of Euphorbia retusa in Mice

Plants provide an alternative source to manage different human disorders due to various metabolites. The aim of this study is to investigate the phytochemical constituents of the methanolic extracts of Euphorbia retusa and to evaluate their antioxidant, anti-inflammatory, and analgesic activities. The phytochemical results obtained by HPLC and by chemical assay reactions have revealed the richness of the methanolic extract of E. retusa in active compounds, in particular polyphenols, flavonoids, and tannins. The methanolic extract shows significant antioxidant activities in vitro, in the DPPH and the FRAP assays. The antinociceptive activity was evaluated using acetic acid and hot-plate models of pain in mice. The anti-inflammatory activity was evaluated by carrageenan-induced paw edema. Oral pretreatment with the methanolic extract of E. retusa (200 mg/kg) exhibited a significant inhibition of pain induced either by acetic acid or by the heating plate and in a manner comparable to the standard drug paracetamol. E. retusa significantly reduced paw edema starting from the 3rd hour after carrageenan administration by increasing the activity of antioxidant enzymes (SOD, CAT, and GPx) in liver and paw tissues and decreasing the levels of MDA. These results may confirm the interesting potential of this plant as a treatment of various inflammatory and pain diseases.

Effects of desipramine on the antioxidant status in rat tissues at carrageenan-induced paw inflammation

The pathogenesis of many diseases and different pathological conditions, including inflammation, is associated with excess production of reactive oxygen species (ROS). The present study aimed to investigate the effects of the antidepressant desipramine (DES) on carrageenan (CG)-induced inflammation, as well as on the endogenous levels of cell enzyme and non-enzyme antioxidants in rat liver and spleen, 4 and 24 h after CG injection. The intra-plantar CG injection into the right hind paw resulted in a time-dependent increase in the paw volume; the maximum of CG-induced edema peak was in 2-4 h. A single DES dose of 20 mg · kg(-1) , administered 30 min before CG, had no effect on paw edema, whereas the higher drug dose used (50 mg · kg(-1) ) suppressed the edematous response to CG. The latter drug dose protected CG-induced decrease of glutathione (non-enzyme antioxidant) in the liver; it did not affect CG-unchanged activities of superoxide dismutase, glutathione peroxidase (enzyme antioxidants) and glucose-6-phosphate dehydrogenase (enzyme, important for the activity of glutathione-conjugated antioxidant enzymes) in both liver and spleen. The drug showed an efficient antioxidant capacity in ROS-generating chemical systems; it was higher than that of fluoxetine (another type of antidepressant). The present results suggest that the good antioxidant activity of DES might contribute to its beneficial effects in liver injuries.

Effects of structural analogues of nociceptin(1-13)NH₂ on brain antioxidant status in kainic acid-treated rats

The in vivo effects of nociceptin (N/OFQ(1-13)NH(2) ) and its structural analogues ([Dab(9) ]N/OFQ(1-13)NH(2) , [Dap(9) ]N/OFQ(1-13)NH(2) and [Cav(9) ]N/OFQ(1-13)NH(2) ) on the levels of lipid peroxidation and cell antioxidants (enzyme and non-enzyme) in brain of control and kainic acid (KA)-treated rats were studied. In control animals, [Dab(9) ]N/OFQ(1-13)NH(2) and [Dap(9) ]N/OFQ(1-13)NH(2) , unlike N/OFQ(1-13)NH(2) and [Cav(9) ]N/OFQ(1-13)NH(2) , slightly increased the brain lipid peroxidation; the rest of the parameters were unchanged by all neuropeptides tested. KA (0.25 µg in 0.5 µl, i.c.v) increased the lipid peroxidation (4 and 24 h after KA-injection) and decreased the glutathione level (1 h after KA-administration). One hour after KA-administration, the neuropeptides (2 µg in 0.5 µl, injected 30 min before KA) showed the following effects: a slight decrease in the KA-induced lipid peroxidation by all nociceptin analogues and an enhancement of the KA-decreased GSH level, but by [Cav(9) ]N/OFQ(1-13)NH(2) only. The brain antioxidant enzyme activities were unchanged in all used experimental groups. In addition, the nociceptin analogues, especially [Can(9) ]N/OFQ(1-13)NH(2) , showed a good antioxidant capacity in chemical systems, generating reactive oxygen species. In conclusion, the substitution of lysin (Lys) in N/OFQ(1-13)NH(2) molecule with other amino acids might contribute to changes in its antioxidant properties. Copyright © 2011 John Wiley & Sons, Ltd.