Abstract
Similar to animals, it has recently been proven that nitro-fatty acids such as nitro-linolenic acid and nitro-oleic acid (NO2-OA) have relevant physiological roles as signalling molecules also in plants. Although NO2-OA is of great therapeutic importance, its presence in plants as a free fatty acid has not been observed so far. Since Brassica napus (oilseed rape) is a crop with high oleic acid content, the abundance of NO2-OA in its tissues can be assumed. Therefore, we quantified NO2-OA in B. napus seeds and differently developed seedlings. In all samples, NO2-OA was detectable at nanomolar concentrations. The seeds showed the highest NO2-OA content, which decreased during germination. In contrast, nitric oxide (•NO) levels increased in the early stages of germination and seedling growth. Exogenous NO2-OA treatment (100 µM, 24 h) of Brassica seeds resulted in significantly increased •NO level and induced germination capacity compared to untreated seeds. The results of in vitro approaches (4-Amino-5-methylamino-2′,7′-difluorofluorescein (DAF-FM) fluorescence, •NO-sensitive electrode) supported the •NO liberating capacity of NO2-OA. We observed for the first time that Brassica seeds and seedlings contain free NO2-OA which may be involved in germination as an •NO donor as suggested both by the results of exogenous NO2-OA treatment of seeds and in vitro approaches. Due to their high NO2-OA content, Brassica sprouts can be considered as a good source of dietary NO2-OA intake.
Highlights
Nitro-fatty acids (NO2 -FA) as endogenous signal molecules in animals and humans have gained great attention, since these nitrated lipid derivatives exert relevant bioactivity in association with anti-thrombotic, cytoprotective, and anti-inflammatory processes.The addition reaction of nitric oxide (NO) and NO-derived higher oxides of nitrogen with conjugated double bond-containing, unsaturated fatty acids results in the formation of NO2 -FA; the in vivo mechanism is still unknown [2]
During the first proposed mechanism, radical hydrogen abstraction from a bis-allylic carbon takes place resulting in the formation of an alkyl radical which is followed by the formation of a peroxyl radical via double bond rearrangement and molecular oxygen insertion
We aimed to examine the putative biological functions of NO2 -Oleic acid (OA) in Brassica seeds and seedlings
Summary
Nitro-fatty acids (NO2 -FA) as endogenous signal molecules in animals and humans have gained great attention, since these nitrated lipid derivatives exert relevant bioactivity in association with anti-thrombotic, cytoprotective, and anti-inflammatory processes (recently reviewed in Ref. [1]).The addition reaction of nitric oxide (NO) and NO-derived higher oxides of nitrogen (peroxynitrite, nitrogen dioxide) with conjugated double bond-containing, unsaturated fatty acids results in the formation of NO2 -FA; the in vivo mechanism is still unknown [2]. This can be followed by further oxidation steps yielding the electrophilic nitro-alkene [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
