[Age-related features of the relationship between the content of vascular endothelial growth factor and indicators of lipid metabolism and extracellular matrix metabolism in men in the European part of the Russian Arctic.]

The content of vascular endothelial growth factor-A (VEGF-A) in blood plasma and its relationship with lipid and extracellular matrix metabolism in working-aged men (19-69 years), living and working in the European part of the Arctic zone of the Russian Federation (Russian Arctic), were studied. No age dependence of the plasma VEGF-A content was found. The correlation analysis, performed in different age groups, revealed significant associations of VEGF-A level with lipid parameters (CS, LDL-C, Apo B, atherogenicity coefficient, Apo B /Apo A1 ratio) and extracellular matrix metabolism (blood TIMP-4, MMP-2, MMP-3, MMP-9, hyaluronan, total and peptide-bound hydroxyproline, glycosaminoglycans). The established correlations indicate the formation of relationships between angiogenesis, atherogenesis and fibrosis at a specific period of life of northerners in the Russian Arctic.

[Age-related dynamics of the contents of matrix metalloproteinases (MMP-1, -2, -3, -9) and tissue inhibitors of matrix metalloproteinases (TIMP-1, -2, -4) in blood plasma of residents of the European part of the Arctic zone of the Russian Federation.]

Here we present the study of enzymes involved in the regulation of extracellular matrix metabolism. It was the first study of this kind in the European part of the Arctic zone of the Russian Federation (AZRF). The contents of matrix metalloproteinases (MMP-1, -2, -3, -9) and tissue inhibitors of matrix metalloproteinases (TIMP-1, -2, -4) were measured in blood plasma of 91 men in AZRF (67o N) and 14 men in Western Siberia. The contents of MMP-1, MMP-9, TIMP-1 and TIMP-4 in plasma of northerners were higher compared to those of the residents of Western Siberia (55o N). Age-related dynamics of MMP and TIMP contents had a mixed trend in northerners. The maximum contents of MMP-1 and MMP-9 and of MMP-3 were observed in 30-39 and 40-49 years old groups, respectively. The contents of these enzymes tended to decease with age. The maximum contents of TIMP-1 and TIMP-2 and of TIMP-4 were in 50-59 and 60-69 years old groups, respectively, while the minimum contents of these enzymes were in the group of young men up to 29 years old. Hyaluronidase activity was minimal in 30-39 years old group and increased with age up to maximum values at 50-59 years old. Age-related imbalance of MMP/TIMP system (MSE content reduction with age vs TIMP content increase in older age groups) can be considered one of the reasons of the identified age-related increase of interstitial fibrosis and premature aging of the northerners.

[Interrelation between the melatonin level and indicators of aging and fibrosis in men in the European part of the Arctic zone of Russian Federation.]

The results of the correlation analysis between the metabolite melatonin - 6-sulfatoxymelatonin (6-SMT) in the urine and the indicators of aging, interstitial fibrosis, the system of antioxidant protection in men in the Arctic are presented. Negative correlation of medium strength between 6-SMT with calendar age, biological age and molecular marker of aging p16INK4a in leukocytes was noted. A relationship of 6-SMT to fibrosis indices was found. It manifested itself in a negative correlation with sulfated glycosaminoglycans in the urine, with collagen markers: free hydroxyproline, peptide-linked hydroxyproline, and total hydroxyproline. Age-related decrease in the level of 6-SMT may be associated with an age-related increase in interstitial fibrosis in northerners. A positive correlation of medium strength between 6-SMT and hormones: free testosterone level (r=0,53, p=0,0002), total testosterone (r=0,43, p=0,003) and cortisol (r=0,33, p=0,007) was shown. Negative correlations of 6-SMT with the content of ceruloplasmin (r=-0,63, p=0,001) and SCORE scale (r=-0,52, p=0,001) indicate the relationship between melatonin and the antioxidant defense system and the risk of cardiovascular pathology.The results of the correlation analysis between the metabolite melatonin - 6-sulfatoxymelatonin (6-SMT) in the urine and the indicators of aging, interstitial fibrosis, the system of antioxidant protection in men in the Arctic are presented. Negative correlation of medium strength between 6-SMT with calendar age, biological age and molecular marker of aging p16INK4a in leukocytes was noted. A relationship of 6-SMT to fibrosis indices was found. It manifested itself in a negative correlation with sulfated glycosaminoglycans in the urine, with collagen markers: free hydroxyproline, peptide-linked hydroxyproline, and total hydroxyproline. Age-related decrease in the level of 6-SMT may be associated with an age-related increase in interstitial fibrosis in northerners. A positive correlation of medium strength between 6-SMT and hormones: free testosterone level (r=0,53, p=0,0002), total testosterone (r=0,43, p=0,003) and cortisol (r=0,33, p=0,007) was shown. Negative correlations of 6-SMT with the content of ceruloplasmin (r=-0,63, p=0,001) and SCORE scale (r=-0,52, p=0,001) indicate the relationship between melatonin and the antioxidant defense system and the risk of cardiovascular pathology.

[Age-related dynamics of the main extracellular matrix components in residents of the Russian Arctic]

The main extracellular matrix components in Arctic residents were studied. Northerners had increased levels of total glycosaminoglycans, hyaluronan, and collagen IV in plasma and both general and peptide-bound hydroxyproline in urine, which indicates an accelerated metabolism of the main extracellular matrix components compared with comparison group (residents of Siberia). Age-related remodeling of extracellular matrix in northerners manifested in changing ratio and quantity of its main components. Levels of total glycosaminoglycans, hyaluronan, fibronectin, hydroxyproline and its fractions increased with age while the level of collagen IV changed insignificantly. Average positive correlation between extracellular matrix components and biological aging indicators is suggestive of relationship between these two processes: aging - which is accelerated in the Arctic and pathological remodeling of extracellular matrix as it is associated with accelerated aging. Changes in local regulation system including those related to matrix metalloproteinases and their tissue inhibitors may be one of the reasons for pathological remodeling of extracellular matrix.

[Quality of life for men of different ages in the russian European North and its relationship with self-reported health and hormonal status]

Assessment of the quality of life for male inhabitants of the Russian European North demonstrated decreased indices of physical health component (the scale of role functioning determined by physical condition) and mental health component (the scales of social functioning and role functioning determined by emotional state and mental health) compared to the inhabitants of Siberia as a comparison group. Men aged up to 29 had the highest values at all scales. The values decreased with age. The most prominent decrease was observed for the scales of general well-being and pain intensity. There was a moderate decrease for the scales of physical functioning, role functioning determined by emotional state, and role functioning determined by physical condition. Quality of life was closely related to self-reported health of northerners, pathological index, molecular marker of aging, and biological age. Negative correlation between these values implies the deterioration of physical and mental health with biological age. The quality of life for northerners also correlated with hormonal status. There was a relationship between testosterone and three scales of physical health components; between cortisol and one scale of physical component; and between both dehydroepiandrosterone sulfate and insulin and the scales of physical and mental components of health. The effect of various hormones on different age groups of northerners was demonstrated.