Analysis of free-radical scavenging of Yerba Mate (Ilex paraguriensis) using electron spin resonance and radical-induced DNA damage.

Mate (MT) is a popular South American beverage that has been used as a traditional medicine for centuries, spurring recent interest in its nutraceutical properties. MT is prepared as an infusion of leaves from the Yerba Mate (llex paraguriensis) tree. MT has been reported to have antioxidant properties in vitro and in vivo, but these have not been fully characterized in terms of effects against specific radicals.

Luteolin and chrysin differentially inhibit cyclooxygenase-2 expression and scavenge reactive oxygen species but similarly inhibit prostaglandin-E2 formation in RAW 264.7 cells.

Inflammation and oxidative stress are associated with cancer, atherosclerosis, and other chronic diseases. Dietary flavonoids have been reported to possess antiinflammatory and antioxidant properties, but their mechanisms of action and structure-activity relations have not been fully investigated. We hypothesized that differences in antioxidant activity between the structurally similar flavones, luteolin and chrysin (differing only in B-ring hydroxylation patterns), would differentially affect inflammation-associated Cox-2 expression and PGE2 formation.

Essiac tea: scavenging of reactive oxygen species and effects on DNA damage.

Essiac, a tea reportedly developed by the Ojibwa tribe of Canada and widely publicized as a homeopathic cancer treatment, is prepared from a mixture of four herbs Arctium lappa, Rumex acetosella, Ulmus rubra and Rheum officinale. Each of these herbs has been reported to possess antioxidant and anti-cancer activity. Essiac itself has also been reported to demonstrate anti-cancer activity in vitro, although its effects in vivo are still a matter of debate.

Metal-induced oxidative stress and signal transduction.

Occupational and environmental exposures to metals are associated with the development of various cancers. Although carcinogenesis caused by metals has been intensively investigated, the mechanisms of action, especially at the molecular level, are still unclear. Accumulating evidence indicates that reactive oxygen species generated by metals may play an important role in the etiology of disease.

Signaling by carcinogenic metals and metal-induced reactive oxygen species.

Epidemiological data indicate that exposure to metal and metalloid species, including arsenic(III), chromium(VI), and nickel(II), increases the risk of cancer, particularly of the lung and skin. Alterations in normal signal transduction as a result of exposure to carcinogenic metals, and to metal-catalyzed reactive oxygen species (ROS) formation, appear to play an important role in the etiology of metal-induced carcinogenesis. Signaling components affected by metals include growth factor receptors, G-proteins, MAP kinases, and nuclear transcription factors.

Resveratrol scavenges reactive oxygen species and effects radical-induced cellular responses.

Scavenging or quenching of the reactive oxygen species (ROS) involved in oxidative stress has been the subject of many recent studies. Resveratrol, found in various natural food products, has been linked to decreased coronary artery disease and preventing cancer development. The present study measured the effect of resveratrol on several different systems involving the hydroxyl, superoxide, metal/enzymatic-induced, and cellular generated radicals.

Hydrogen peroxide formation and actin filament reorganization by Cdc42 are essential for ethanol-induced in vitro angiogenesis.

This report focuses on the identification of the molecular mechanisms of ethanol-induced in vitro angiogenesis. The manipulation of angiogenesis is an important therapeutic approach for the treatment of cancer, cardiovascular diseases, and chronic inflammation. Our results showed that ethanol stimulation altered the integrity of actin filaments and increased the formation of lamellipodia and filopodia in SVEC4-10 cells.