No abstract

The antinociceptive and antiinflammatory activities of the ethanol extract of the aerial part of Urtica urens were determined by experimental animal models. U. urens extract was found to possess significant antinociceptive activity in chemically induced mouse pain models (ED₅₀ 39.3 mg/kg: 17.2-74.5 mg/kg) in the writhing test and 62.8% inhibition of the licking time in the late phase of the formalin test at a dose of 500 mg/kg p.o. and antiinflammatory activity on carrageenan-induced rat hind paw edema (41.5% inhibition at a dose of 300 mg/kg i.p.). The extract displayed activity neither in the thermal model of pain nor in the topical inflammation model. The major component of the extract was determined as chlorogenic acid (670 mg/1000 g dry weight) and could be partly responsible for this activity.

Vicenin-2 (1), a flavonoid glycoside, was isolated and identified from an ethanol extract of the aerial parts of Urtica circularis. This crude extract was found to possess significant anti-inflammatory activity in a carrageenan-induced rat hind paw edema model (41.5% inhibition at a dose of 300 mg/kg; ip). The effects of 1 on several inflammatory mediators were investigated. In cultured murine macrophages, this compound modified LPS-induced total nitrite and TNF-α production, in addition to the LPS-induced translocation of the nuclear factor NF-κB.

BackgroundUrera aurantiaca is an Argentinean species that has been traditionally used to treat symptoms of inflammation. The aim of this study was to determine and compare the anti-inflammatory and antioxidant effects of two specimens of Urera aurantiaca obtained in the provinces of Salta and Misiones, which are two different geographical areas of Argentina.MethodsThe anti-inflammatory activity of the extracts was tested in LPS-stimulated macrophages through the DPPH radical scavenging activity, the SOD-like activity, the reducing power and the inhibition of lipid peroxidation. The anti-inflammatory activity was also evaluated by the inhibition of albumin denaturation and proteinase inhibitory action tests. The total polyphenols, flavonoids and tannins content were quantified.ResultsBoth extracts were able to reduce the augmented NO release in LPS-activated macrophages and showed antioxidant and in vitro anti-inflammatory activities. The polyphenols content was higher in the extract obtained from the specimen from Salta than in that obtained in Misiones. This finding accounts for the higher anti-inflammatory and antioxidant properties obtained with the former.ConclusionThe differences in chemical composition and the biological activities observed between the extracts are probably related to the different environmental conditions found in both provinces.Electronic supplementary materialThe online version of this article (10.1186/s13020-018-0181-1) contains supplementary material, which is available to authorized users.

Background Oxidative stress is an imbalance between the levels of reactive oxygen species (ROS), reactive nitrogen species (RNS) and endogenous antioxidants. The aetiology and pathogenesis of several oral diseases are attributed to this process. The antioxidant enzymes secreted in the saliva by submandibular glands maintain oral health through the scavenging of ROS. The objective of this work was to study the capacity of an aqueous extract of L. divaricata (AE), and its majority compound, nordihydroguariaretic acid (NDGA), to modulate the pro-oxidant/antioxidant status in submandibular glands in a model of oxidative stress induced by streptozotocin (STZ) in rats. Methods To induce oxidative stress with STZ, a group of animals was treated i.p. with 1 X PBS (control group) and other group was injected i.p. once with STZ (60 mg/kg). Ten days after the treatment, blood samples were taken from the tail vain to determine the glucose levels. Animals with glucose values ≥300 mg/ml were selected. The submandibular glands of control and STZ treated animals were incubated with either the AE (500 μg/ml) or with NDGA (1.5 μg/ml), and the content of malondialdehyde (MDA), protein carbonyl groups, ROS and RNS, and the activity and expression of peroxidase (Px), superoxide dismutase (SOD) and inducible nitric oxide synthase (iNOS) were assayed. Results AE decreased the levels of MDA ( ## P < 0.01) and protein carbonyl groups ( # P < 0.05), and modulated the levels of ROS such as hydrogen peroxide (H 2 O 2 )( ## P < 0.01), superoxide anion (O 2 .- ) ( # P < 0.05) and nitric oxide (NO) ( # P < 0.05) in relation to the modulation of Px and iNOS expression. NDGA was found to be involved in these effects. Conclusions The antioxidant activity of the AE in the submandibular glands would allow the maintenance of the antioxidant pool to prevent oral oxidative diseases.

Urera aurantiaca Wedd. (Urticaceae) is a medicinal plant commonly used in traditional medicine to relieve pain in inflammatory processes. In the present study, the in vivo anti-inflammatory and antinociceptive effects of U. aurantiaca methanolic extract and its possible mechanisms of action were investigated. The extract showed anti-inflammatory activity in the ear edema in mice test (34.3% inhibition), myeloperoxidase (MPO) activity was markedly reduced in animals administered with the extract: within 49.6% and 68.5%. In the histological analysis, intense dermal edema and intense cellular infiltration of inflammatory cells were markedly reduced in the ear tissue of the animals treated with the extract. In the carrageenan-induced hind paw edema in rats assay the extract provoked a significant inhibition of the inflammation (45.5%, 5 h after the treatment) and the MPO activity was markedly reduced (maximum inhibition 71.7%), The extract also exhibited significant and dose-dependent inhibitory effect on the increased vascular permeability induced by acetic acid. The extract presented antioxidant activity in both 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis 3-ethylbenzothiazoline 6-sulfonic acid tests and its total phenol content was 35.4 ± 0.06 mg GAE/g of extract. Also, the extract produced significant inhibition on nociception induced by acetic acid (ED50 : 8.7 mg/kg, i.p.) administered intraperitoneally and orally. Naloxone significantly prevented this activity.

Tilia species have been used in Europe and in America to treat anxiety and also for the treatment of colds, influenza, bronchitis, fever and inflammation. Tilia × viridis is a Tilia species distributed widely in Buenos Aires, Argentina. The flavonoids present in Tilia species have antioxidant properties, acting as reactive oxygen species (ROS) scavengers, principally on hydrogen peroxide (H(2)O(2)) and the superoxide anion (O(2)(·-)), which are involved in many diseases, including cancer. The aim of this study was to determine the phytochemical pattern of the ethanol extract of Tilia × viridis, principally the flavonoid content, and to evaluate the antiproliferative effects on both normal and tumoral cells, and the antioxidant activity in relation to H(2)O(2) modulation. The extract was found to present a selective antiproliferative activity on a lymphoma cell line and this was related to free radical scavenging activity. In addition, one of its main compounds, rutin, showed antioxidant effects related to peroxidase activity. T. × viridis may therefore be a source of antioxidant compounds that contribute to a selective antiproliferative action on tumoral cells, acting by modulation of H(2)O(2) levels.

No abstract