The O2−-producing complex of NADPH-containing protein component with Fe (III) was isolated and purified from Armenian fruits: raspberries, apricots, grapes, and grape seeds for the first time. The high thermostability of these complexes is quite possible, conditioned with the action at the high-temperature metabolic process (to 280 °C, at nanosecond) for some proteins (catalase, peroxidases, etc.).
The NADPH oxidase (Nox)-mediated release of ROS in oxidative burst represents it as an inflammatory mediator [4]. Over time, superoxide generation through Nox was thought to occur only in phagocytes; however, several enzymes responsible for ROS production have been recently identified in various tissues. These enzymes show similarities to phagocyte Nox and are collectively referred to as the Nox family. The Nox genes produce the transmembrane proteins responsible for transporting electrons across biological membranes, thereby the reduction of oxygen into superoxide [5]. Nox enzymes mediate different functions in various organisms through redox signaling. The importance of ROS in host immunity has been clearly determined in the genetic disorder, CGD, which reflects defects in Nox [23] and results in improper neutrophil killing during phagocytosis [24, 25].
Actually, by changing the concentration of isoforms of NCP-Fe (III) complexes and other conditions (temperature, time) of the reaction, it is possible to regulate the steady-state concentration of the produced O2−. This testifies about the controllability of the steady-state concentration of O2− in the above biological systems, when determining the effect of the produced O2− in empirically low and high concentrations on the process of proliferation and apoptosis of cells, as well as determining the antibacterial, anticancer and antiviral effects of O2− produced by these thermo-stable systems [26,27,28,29].
However, after the association of NCP with the total fraction of Nox isoforms (Nox1+Nox2) obtained from the membranes of erythrocytes and leukocytes of donor blood, the formed hybrid associates (0.2 mg/ml each) oxidize adrenaline to adrenochrome almost at intensity that it took place under the action of isoforms NCP-Fe (III). It is possible that in case of immunodeficiency caused by a decrease in the O2− -producing activity of leukocytes Nox, the NCP isoforms can increase the O2−—producing activity of Nox on the surface of leukocytes membranes [30].
For the first time, the mechanism of direct production of O2− by the isoforms of NCP-Fe (III) from these fruits and the grape seeds’ isoforms when passing an electron from the NADPH group of NCP to Fe (III), followed by transfer to O2, thereby reducing it to O2− had been revealed. Isoforms of the NCP-Fe (III) complex continuously produced O2− under aerobic conditions. After the removal of Fe (III) ions from the NCP-Fe (III) complex, NCP isoforms exhibited only a reducing effect and stimulated the production of O2− by isoforms of NADPH oxidases (Nox), in particular, of Nox from the membranes of immune cells (erythrocytes and leukocytes) by creating a hybrid associate (hNCP-Nox).
It is well known, that in systems for the production of O2−, in particular, during the depletion of hydrogen peroxide with alkali (KOH) [31] or ammonia [32], along with O2− the highly toxic to biosystems hydroxyl radicals are formed; beyond this, hydrogen peroxide is also available, the toxicity of which is known rather well. The produced O2− by isoforms of the NCP-Fe (III) complex or by the hybrid associate hNCP-Nox obtained from raspberries, apricots, grape, and the grape seeds were practically pure and did not contain other reactive oxygen species. NCP-Fe (III) and the hybrid associate hNCP-Nox continuously and intensively produced O2− in the controlled steady-state concentrations. This fact seems to be more promising for determining the molecular mechanisms of action by the controlled steady-state concentrations of O2− on various biosystems, considering their high thermo-stability (they were not inactivated when heated in boiled water 8–10 min), which gives birth to real prospects for determining the mechanisms of redox metabolic processes with the participation of O2− at the high temperatures.
According to our data, a relatively increased activity of Nox1 + Nox2 in the processes of adrenaline oxidation in EM (58.4%, 66.7%) and LM (64.2%, 69%), as well as of formazan reduction in EM (72%, 74%) and LM (80.6%, 82.8%) was observed both in the homogeneous and heterogeneous phases due to the presence of the grapes seeds.
Some increase in the stationary concentration of O2− in the heterogeneous phase is related to the fact that on the surface of EM or LM there is already located the O2− producing Nox1 + Nox2 associated with NADPH containing lipoprotein which constantly produces O2− under the aerobic conditions [6]. At the same time under the above-mentioned conditions, O2−- producing activity of leukocytes Nox is more (3–4 times) than that of the erythrocytes Nox, however, the content of erythrocytes is far superior to that of leukocytes. At the same time, erythrocytes like leukocytes are also components of the immune system [33].
Thus, there are some perspectives for using the NCP-Fe (III) complex from the grape seeds as an energetic, natural, and relatively stable O2− production system, and so a natural bactericidal and antiviral agent [26]. NCP obtained from the mentioned sources can be used as a natural agent for decreasing O2− producing activity of Nox isoforms of EM and LM in weakened immunity (immune deficiency) of mammals [30] experimentally and clinically in perspective.
As we have already mentioned above, these NCP-Fe (III) complexes in a lyophilized state, especially in the nitrogen presence, practically don’t lose their O2−-producing activity when kept at −10 to−150C throughout the year. Loss of activity is not observed after the dissolution of NCP-Fe (III) or NCP in в 0.01 M PPB (pH7.4) with saline either. It serves as an opportunity to introduce NCP into the blood of animals. It should be noted that an analogous agent (suprol) from the females’ placenta blood did not cause any adverse unfavorable effects after injection into white rats even in much more amounts than in the norm, and moreover, the introduced suprol has an antitumor effect [34, 35].
In a lyophilized state, under the anaerobic conditions, the isoforms of the given complexes, hybrid associates, and NCP were stored practically without losing their O2−-producing activity in 1–1.5 years.