Ultrastructural features of blood cells in HIF-1α gene variations in specialists of extreme conditions

Abstract

The peculiarities of changes in the ultrastructure of blood cells due to personalized variations of the HIF-1α gene under hypoxic loading (breathing by gas mixture with reduced oxygen content up to 12% and achieving hypoxic state during heavy physical training on bicycle ergometer) were conducted.It was shown that allelic polymorphism of the HIF-1α gene influence on hypoxicinduced changes in the ultrastructure (and therefore function) of blood cells -the C / C genotype of winterers indicates their greater adaptive capacity compared to the C / T genotype that lies in the increasing the number of δ-granules in platelets, and reducing the number of αgranules and tubules of the inner skeleton. Such changes primarily indicate an increase in serotonin depot and therefore, indirectly, an increase in the contractile activity of the vascular wall, which may serve as a marker of the formation of adaptive reaction in response to hypoxic effects and stress. This is also indicated by the moderate swelling of mitochondria with an increase in their average diameter by 31%, which is considered to be a sign of an 219 increase in the energy capacity of the mitochondrial apparatus in order to replenish ADP and ATP reserves for the further inclusion of adaptive responses. Hypoxic loading in winterers with C / T-genotype led to overstressing of platelet function with decrease in contractile activity of the vascular wall.The number of mitochondria in leukocytes significantly increased (by 24%) in winterers with C / C genotype; not only mitochondrial morphogenesis was activated, but also dynamic processes, in particular the association of organelles with pronounced longitudinal association and / or the formation of bridges between mitochondria. These facts are considered as an indicator of information exchange in the cell mitochondrial apparatus. In leukocytes of winterers with C / T genotype, changes in the mitochondrial apparatus were of a different nature: there were clear signs of hypoxic damage of organelles and the total percentage of structurally altered mitochondria exceeded 21%.

Oxygen Supply System Management in an Overweight Adult after 12 Months in Antarctica—Study Case

“…Conditions enabling to maintain optimal oxygen homoeostasis at overweight were worse as indicated by significant hypoxemia—decrease in p a O 2 from 93 to 83.8 mm Hg (see Table 2 ). The decrease in the level of working capacity can be indirectly judged by the existing dysfunction of the mitochondrial apparatus, which was found in all members of the expedition in addition to the examined one [ 13 ]. This is confirmed by the data of bicycle ergometric testing carried out before and after being a member of the expedition in Antarctica [ 10 ].…”

“…Antarctica is a unique place to study health conditions under the influence of environmental factors on the organism in pure form [ 10 , 11 , 12 , 13 , 14 , 24 ].…”

“…Medical research in Antarctica opens up new horizons of understanding across a spectrum of individual health conditions under stress and unusual environmental conditions [ 24 ]. The series of the retrospective and prospective studies demonstrated the strong influence of extreme environmental factors and stress in the absence of man-made factors on health parameters, with clearly defined individually patterned reactions [ 10 , 11 , 12 , 13 , 14 , 24 , 25 , 26 ].…”

“…In Europe, it is not possible to model conditions that are devoid of technogenic influences as is possible with Antarctic conditions. Also, factors provoking the development of disorders of oxygen delivery at all stages of mass-transfer may be due to disorders of the central regulation of desynchronizes as impaired sleep–wakefulness rhythm disorders and autonomic regulation [ 10 , 11 , 12 , 13 , 14 ]. All of the points above, including the conditions of forced hypodynamia, contribute to body weight gain and the greater the weight gain, the more pronounced the disturbances in the level of oxygen delivery due to an increase in the load on the heart and the function of external respiration.…”

“…Research on the effect of weight gain was carried out with the participation of many station crews and all the studies were complex (the functions of all systems were tested before and after the expedition) and throughout the stay, the cycles were measured quarterly, and anthropometric indicators were recorded monthly (weight, height, and percentage body fat), vital capacity, electrocardiography, clinical blood tests, daily body temperature, blood pressure, heart rate, psychological examination, as well as daily monitoring of autonomic regulation indicators and sleep quality test. The results indicated one-way changes in body weight and the examination of functions with a clear tendency towards the development of maladaptive disorders and symptoms of latent hypoxia [ 10 , 11 , 12 , 13 , 14 ]. Therefore, in order to thoroughly understand latent hypoxia and the mechanisms of association with increased overweigh, targeted studies were conducted involving the average (based on screening results) nominate with the highest weight gain.…”