Suchergebnisse

Apart from their functions in the nervous system of animals, neurotransmitters operate as
regulatory agents and signals in diverse kingdoms of life. Many neurotransmitters at low
concentrations exert specific effects on microalgae, predominantly functioning as algal growth
stimulators. Neurotransmitters that promote microalgal biomass accumulation and enhance the
synthesis of lipids, polysaccharides, and other valuable products are of much potential
biotechnological interest in terms of projects aimed at producing "algal" drugs and food
additives, as well as biodiesel and other kinds of biofuel. Some microalgal species synthesize
their own neurotransmitters and/or facilitate their synthesis by the symbiotic microbiota in the
gastro-intestinal tract and, therefore, are expected to promote human physical and mental
health. Microalgae can exert neuroprotective effects; nevertheless, many microalgae produce
toxins affecting the functioning of the nervous system.

Neurotransmitters are found not only in animals, but also in other living organisms, including plants. They are found in other living organisms, including plants. However, the data on the functions of these compounds in the plant world are far from being comprehensive. In particular, the issue concerning their impact on plant cell death still awaits further research. In the present work, the effects of neurotransmitters on programmed cell death and the formation of reactive oxygen species (ROS) in plants were tested. Programmed cell death was estimated from the destruction of cell nuclei, and ROS was determined using 2ʹ,7ʹ-dichlorofluorescein. Dopamine, norepinephrine, serotonin, histamine, acetylcholine and its synthetic analog acetylthiocholine were used. The catecholamines dopamine and norepinephrine at concentrations of 0.01-1 mM suppressed the destruction of guard cell nuclei in the epidermis of pea leaves, which was caused by KCN. Serotonin and acetylcholine at a concentration of 1-3 mM, on the contrary, increased the destruction of nuclei that was induced by KCN. Histamine and acetylthiocholine had no effect on KCN-dependent destruction of nuclei at concentrations of 0.01-3 mM. Acetylthiocholine at a concentration of 3 mM, in contrast to natural neurotransmitters, caused the destruction of guard cell nuclei in the absence of KCN. Dopamine, norepinephrine, and serotonin reduced the formation of ROS in the epidermis of pea leaves, which was induced by menadione. Histamine, acetylcholine and acetylthiocholine did not have a similar effect. The results demonstrate that dopamine, norepinephrine and serotonin have antioxidant properties in plants. In addition, dopamine and norepinephrine can prevent cell death.