Search results for "Rite"
showing 10 items of 2726 documents
Effect of selected triterpenoids on chronic dermal inflammation.
1997
The activity of four natural triterpenoids on a 12-O-tetradecanoylphorbol-13-acetate multiple-dose model of skin chronic inflammation was studied. Erythrodiol and ursolic acid were significantly effective. The most important features concerning structure-activity relationship and previous data on the effect of these triterpenoids on other inflammatory conditions are discussed.
Chemical Constituents and Pharmacological Properties ofPoria cocos
2011
Poria cocos (Polyporaceae) is a saprophytic fungus that grows in diverse species of Pinus. Its sclerotium, called fu-ling or hoelen, is used in traditional Chinese and Japanese medicine for its diuretic, sedative, and tonic effects. Various studies of this fungus have demonstrated its marked anti-inflammatory activity in different experimental models of acute and chronic inflammation. It is widely used as a constituent of many preparations in Asian medicine, but the number of research papers on its clinical properties is insufficient for establishing its efficacy and safety from a scientific point of view. In this review, we have compiled all the published data concerning the chemistry, pha…
Zanhasaponins A and B, Antiphospholipase A2 Saponins from an Antiinflammatory Extract of Zanha africana Root Bark
1997
A MeOH extract from Z. africana was examined for topical antiinflammatory activity and proved to be active against arachidonic acid (AA) acute edema, 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced chronic inflammation, and oxazolone delayed-type hypersensitivity in mice. The extract also showed significant inhibitory activity of Naja naja phospholipase A2 when a polarographic method was used. Two oleanane-type triterpene saponins, zanhasaponins A (1) and B (2), and the cyclitol pinitol (4), isolated from the extract, were active as inhibitors of PLA2. A further saponin, zanhasaponin C (3) was inactive in this assay.
Possible Fungistatic Implications of Betulin Presence in Betulaceae Plants and their Hymenochaetaceae Parasitic Fungi
2010
Betulin and its derivatives (especially betulinic acid) are known to possess very interesting prospects for their application in medicine, cosmetics and as bioactive agents in pharmaceutical industry. Usually betulin is obtained by extraction from the outer layer of a birch bark. In this work we describe a simple method of betulin isolation from bark of various species of Betulaceae trees and parasitic Hymenochaetaceae fungi associated with these trees. The composition of the extracts was studied by GC-MS, whereas the structures of the isolated compounds were confirmed by FTIR and 1H NMR. Additionally, the significant fungistatic activity of betulin towards some fi lamentous fungi was deter…
Bioactive saponins from plants: An update
2000
Plant saponins are a group of naturally occuring triterpene or steroid glycosides which include a large number of biologically and pharmacologically active compounds. Saponins have been shown in both in vitroand in vivoexperimental test systems during the last decade to possess a broad spectrum of biological and pharmacological activities. This review will summarize some of the recent advances concerning cancer-related activity, immunostimulating, immunoadjuvant, antihepatotoxic, antiphlogistic, antiallergic, molluscicidal, hemolytic, antifungal, antiviral, and hypoglycemic activities. In addition, the effects on the cardiovascular system and the central nervous system will be discussed tog…
Drugs modulating the biological effects of peroxynitrite and related nitrogen species.
2007
The term “reactive nitrogen species” includes nitrogen monoxide, commonly called nitric oxide, and some other remarkable chemical entities (peroxynitrite, nitrosoperoxycarbonate, etc.) formed mostly from nitrogen monoxide itself in biological environments. Regardless of the specific mechanisms implicated in their effects, however, it is clear that an integrated pharmacological approach to peroxynitrite and related species is only just beginning to take shape. The array of affected chemical and pathological processes is extremely broad. One of the most conspicuous mechanisms observed thus far has been the scavenging of the peroxynitrite anion by molecules endowed with antioxidant activity. T…
Free radical biology of the cardiovascular system
2012
Most cardiovascular diseases (CVDs), as well as age-related cardiovascular alterations, are accompanied by increases in oxidative stress, usually due to increased generation and/or decreased metabolism of ROS (reactive oxygen species; for example superoxide radicals) and RNS (reactive nitrogen species; for example peroxynitrite). The superoxide anion is generated by several enzymatic reactions, including a variety of NADPH oxidases and uncoupled eNOS (endothelial NO synthase). To relieve the burden caused by this generation of free radicals, which also occurs as part of normal physiological processes, such as mitochondrial respiratory chain activity, mammalian systems have developed endogen…
Mechanism of interaction of betanin and indicaxanthin with human myeloperoxidase and hypochlorous acid.
2005
Hypochlorous acid (HOCl) is the most powerful oxidant produced by human neutrophils and contributes to the damage caused by these inflammatory cells. It is produced from H2O2 and chloride by the heme enzyme myeloperoxidase (MPO). Based on findings that betalains provide antioxidant and anti-inflammatory effects, we performed the present kinetic study on the interaction between the betalains, betanin and indicaxanthin, with the redox intermediates, compound I and compound II of MPO, and its major cytotoxic product HOCl. It is shown that both betalains are good peroxidase substrates for MPO and function as one-electron reductants of its redox intermediates, compound I and compound II. Compoun…
Organic Nitrates and Nitrate Tolerance—State of the Art and Future Developments
2010
The hemodynamic and antiischemic effects of nitroglycerin (GTN) are lost upon chronic administration due to the rapid development of nitrate tolerance. The mechanism of this phenomenon has puzzled several generations of scientists, but recent findings have led to novel hypotheses. The formation of reactive oxygen and nitrogen species in the mitochondria and the subsequent inhibition of the nitrate-bioactivating enzyme mitochondrial aldehyde dehydrogenase (ALDH-2) appear to play a central role, at least for GTN, that is, bioactivated by ALDH-2. Importantly, these findings provide the opportunity to reconcile the two “traditional” hypotheses of nitrate tolerance, that is, the one postulating …
Ursolic acid ameliorates stress and reactive oxygen species in C. elegans knockout mutants by the dopamine Dop1 and Dop3 receptors.
2020
Abstract Background Depression and stress-related disorders are leading causes of death worldwide. Standard treatments elevating serotonin or noradrenaline levels are not sufficiently effective and cause adverse side effects. A connection between dopamine pathways and stress-related disorders has been suggested. Compounds derived from herbal medicine could be a promising alternative. We examined the neuroprotective effects of ursolic acid (UA) by focusing on dopamine signalling. Methods Trolox equivalent capacity assay was used to determine the antioxidant activities of UA in vitro. C. elegans N2 wildtype and dopamine receptor-knockout mutants (dop-1-deficient RB665 and dop-3-deficient LX70…