Chapters authored
Oxidative Stress: Noxious but Also Vital By Margarete Dulce Bagatini, Jeandre Augusto dos Santos Jaques,
Carla Santos de Oliveira, Graciele Almeida de Oliveira, Micheli
Mainardi Pillat, Aline Mânica, Cintia dos Santos Moser, Lucas
Derbocio dos Santos and Henning Ulrich
The imbalance between reactive oxygen species (ROS) production and antioxidant defenses determines the condition called oxidative stress. When there is an increase in ROS production or a decrease in the antioxidant defenses, this systemic antioxidant/pro-oxidant imbalance may lead to the accumulation of oxidative damage, which, in turn, may lead to a modification of biomolecules. These consist of reactions resulting in protein adducts, DNA oxidation, and formation of lipid peroxides, which, in turn, reduce the cellular functional capacity and increase the risk of disease development. The body has natural scavenging systems against free radicals and other reactive species. However, sometimes the endogenous antioxidant capacity is exceeded by the production of ROS. When this occurs, exogenous antioxidants exert important function for the human health. These bioactive compounds act preventing and neutralizing the formation of new reactive species and free radicals. In some cases, an increase of ROS can help the host to resolve an infection or even to control the tumor growth. Finally, the levels of ROS can be perceived by signal transduction pathways involving known targets (i.e., p53, Ras, and NF-κB) and regulate physiopathological events such as the cellular cycle, apoptosis, and inflammation.
Part of the book: Novel Prospects in Oxidative and Nitrosative Stress
Crosstalk between the Purinergic and Immune Systems: Implications for the Glutathione Antioxidant System in Health and Disease By Charles Elias Assmann, Naiara Stefanello, Nathieli Bianchin Bottari, Jucimara Baldissarelli, Maria Rosa Chitolina Schetinger, Vera Maria Melchiors Morsch and Margarete Dulce Bagatini
Glutathione (GSH) represents the major nonprotein thiol in cells and, alongside with glutathione-dependent enzymes such as glutathione reductase (GR), glutathione peroxidase (GPx), and glutathione S-transferase (GST), exerts several biological functions including the protection against free radicals and other essential metabolic reactions within the body. Disturbances in the homeostasis of this complex glutathione antioxidant system may damage cells and have been implicated with the development and progression of several human diseases. In this context, the immune and purinergic systems are also essential, since the dysregulation in both systems may also be correlated with numerous diseases. These two networks are closely related and control inflammatory responses, especially by the crosstalk of signaling molecules, receptors, and enzymes; thus, they can exacerbate or slow down the progression of diseases. Based on this background, we aimed to provide a general scenario of the purinergic and immune systems and the connection between both and the modulation of glutathione and glutathione-dependent enzyme expression and activity in the context of health and disease.
Part of the book: Glutathione System and Oxidative Stress in Health and Disease
The Potential of the Purinergic System as a Therapeutic Target of Natural Compounds in Cutaneous Melanoma By Gilnei Bruno da Silva, Daiane Manica, Marcelo Moreno and Margarete Dulce Bagatini
Cutaneous melanoma is an aggressive and difficult-to-treat disease that has rapidly grown worldwide. The pharmacotherapy available in so many cases results in low response and undesirable side effects, which impair the life quality of those affected. Several studies have been shown that the purinergic system is involved in cancer context, such as in cutaneous melanoma. With technological advances, several bioactive compounds from nature are studied and presented as promising adjuvant therapies against cancer, as phenolic compounds and related action by purinergic system modulations. Thus, phenolic compounds such as rosmarinic acid, resveratrol, tannic acid, as well as vitamin D may be promising substances in a therapeutic perspective to treat cutaneous melanoma via purinergic system pathway. More research needs to be done to open up new horizons in the treatment of melanoma by the purinergic signaling.
Part of the book: Purinergic System
