1.
Carotenoid research: History and new perspectives for chemistry in biological systems.
Britton, G
Biochimica et biophysica acta. Molecular and cell biology of lipids. 2020;(11):158699
Abstract
The history of carotenoid research as this progressed from chemistry to biochemistry and biology is outlined. Proposed roles of carotenoids in eye health, as antioxidants, and in protection against cancer and other degenerative diseases, as well as stimulatory effects on the immune system and metabolism are covered. Proposed biological actions must be consistent with the chemistry of carotenoids in the largely aqueous biological systems, which may differ from the known chemistry of carotenoids in organic solvents. In particular, carotenoids tend to form aggregates. The effects of this aggregation and of other molecular interactions in vivo are likely to be crucial to biological activity. These perspectives of the chemistry of carotenoids and carotenoid free radicals are examined and the need for carotenoid samples used in experimental work to be pure and free from breakdown products and pro-oxidant peroxides is emphasised. This article is part of a Special Issue entitled Carotenoids recent advances in cell and molecular biology edited by Johannes von Lintig and Loredana Quadro.
2.
Free radical-mediated systemic immunity in plants.
Wendehenne, D, Gao, QM, Kachroo, A, Kachroo, P
Current opinion in plant biology. 2014;:127-34
Abstract
Systemic acquired resistance (SAR) is a form of defense that protects plants against a broad-spectrum of secondary infections by related or unrelated pathogens. SAR related research has witnessed considerable progress in recent years and a number of chemical signals and proteins contributing to SAR have been identified. All of these diverse constituents share their requirement for the phytohormone salicylic acid, an essential downstream component of the SAR pathway. However, recent work demonstrating the essential parallel functioning of nitric oxide (NO)-derived and reactive oxygen species (ROS)-derived signaling together with SA provides important new insights in the overlapping pathways leading to SAR. This review discusses the potential significance of branched pathways and the relative contributions of NO/ROS-derived and SA-derived pathways in SAR.
3.
Reduction of free radicals in multiple sclerosis: effect of glatiramer acetate (Copaxone).
Iarlori, C, Gambi, D, Lugaresi, A, Patruno, A, Felaco, M, Salvatore, M, Speranza, L, Reale, M
Multiple sclerosis (Houndmills, Basingstoke, England). 2008;(6):739-48
Abstract
Free radicals have been found in high concentrations within inflammatory multiple sclerosis (MS) lesions. The superoxide anion (O(2)(-)) reacts rapidly with nitric oxide (NO), producing peroxynitrite (ONOO(-)). Glatiramer acetate (GA) is a specific MS immunomodulator that induces the synthesis of Th2 cytokines, and reduces the frequency of relapses and the formation of active brain lesions. Proinflammatory cytokines could play a role in free radicals production in the peripheral immune system as well as in the central nervous system (CNS). The effect of GA on iNOS, superoxide radicals (O(2)(-)) and 3-nitrotyrosine production by peripheral blood adherent mononuclear cells (PBAMs) was assessed. Our findings demonstrate that in vitro GA reduced spontaneous and LPS-induced iNOS, 3-nitrotyrosine, NO and O(2)(-) production, and that similar inhibition can be demonstrated ex vivo in mononuclear cells obtained from GA-treated patients. The inhibition of the production of free radicals in PBAMs may represent a new therapeutic mechanism against inflammation during MS.