RATIONALE Enhanced production of reactive oxygen species (ROS), capable of reducing endogenous defense levels and enhancing inflammation, is suggested to play a role in sarcoidosis. Antioxidant supplementation might offer protection against such ROS-mediated damage. A promising candidate for antioxidant supplementation is the flavonoid quercetin. AIM To determine the antioxidant and inflammat...

Oxidative stress caused by an imbalanced metabolism and an excess of reactive oxygen species (ROS) lead to a range of health disorders in humans. Our endogenous antioxidant defense mechanisms and our dietary intake of antioxidants potentially regulate our oxidative homeostasis. Numerous synthetic antioxidants can effectively improve defense mechanisms, but because of their adverse toxic effects...

BACKGROUND Friedreich ataxia originates from a decrease in mitochondrial frataxin, which causes the death of a subset of neurons. The biochemical hallmarks of the disease include low activity of the iron sulfur cluster-containing proteins (ISP) and impairment of antioxidant defense mechanisms that may play a major role in disease progression. METHODOLOGY/PRINCIPAL FINDINGS We thus investigate...

Once the cells are challenged by intraand extracellular environmental stimuli such as nitric oxide, calcium and pathogenic organisms, the oxidative balance between reactive oxygen species (ROS) (such as O 2 , H 2 O 2 , OH·) production and antioxidant defense systems (such as glutathione reductase and catalase) is broken, resulting in accumulation of ROS within cells. ROS is linked with various ...

Imbalance in the antioxidant defense system leads to detrimental consequences, such as neurological disorders. The Nrf2 signaling is known as a main pathway involved in cellular defense system. Nrf2 is a transcription factor that regulates oxidative stress response by inducing expression of various antioxidant enzyme genes. In this study, we screened several pure natural compounds for Nrf2 acti...

Aerobic organisms possess antioxidant defense systems that deal with reactive oxygen species (ROS) produced as a consequence of aerobic respiration. Reactive oxygen is related to both, the arrest of growth and the start of cell differentiation. Low concentrations of reactive oxygen intermediates may be beneficial or even indispensable in processes such as intracellular messaging and defense aga...

The erythrocytes represent an important source of antioxidant capacity of the blood. Catalase (EC 1.11.1.6.) is one of the enzymatic components of their antioxidant defense system. The objective of this study was to follow erythrocyte catalase (CAT) in 7-, 15-, 21-, 35-, 60- and 90-day-old Wistar rats of both sexes in normoxia and after exposure to intensive acute hypobaric hypoxia. During the ...

All classic, non-surgical anticancer approaches like chemotherapy, radiotherapy or photodynamic therapy kill cancer cells by inducing severe oxidative stress. Even tough chemo- and radiotherapy are still a gold standard in cancer treatment, the identification of non-toxic compounds that enhance their selectivity, would allow for lowering their doses, reduce side effects and risk of second cance...