Dynamics Of Age-related Changes Research Articles

Kynurenine’s Effect on the Different Stages of Osteoblastic Differentiation

This study focuses on the dynamics of age-related changes in osteoblasts’ matrix production, with a specific focus on the involvement of the aryl hydrocarbon receptor (AhR). The AhR is activated by kynurenine, a metabolite of the amino acid tryptophan that tends to increase with age. Kynurenine has been known to impair osteoblasts’ bone formation ability, however, the point at which this occurs is unknown. The study utilizes a 21-day differentiation process of mesenchymal stem cells. “Window experiments” that vary the intervals of kynurenine treatment to explore its impact at different stages of osteoblast development were utilized. The experimental setup involves four distinct conditions: a control group with a vehicle, a group treated with kynurenine, a group with an AhR antagonist (BAY), and a group treated with both kynurenine and BAY. The AhR antagonist, specifically BAY2416964, serves to investigate whether any observed effects of kynurenine are mediated through AhR signaling. Results, analyzed through alizarin red staining, demonstrate a notable negative impact of kynurenine on matrix production, particularly in the middle stages of osteoblast differentiation. The study further employs crystal violet staining to confirm the presence of cells in the experimental wells, providing assurance of the reliability of the alizarin staining procedure. Importantly, this staining procedure also suggests that the effects of kynurenine on mineralized matrix production are largely independent of any potential impacts on cell viability.

Kynurenine’s Effect on the Different Stages of Osteoblastic Differentiation

This study focuses on the dynamics of age-related changes in osteoblasts’ matrix production, with a specific focus on the involvement of the aryl hydrocarbon receptor (AhR). The AhR is activated by kynurenine, a metabolite of the amino acid tryptophan that tends to increase with age. Kynurenine has been known to impair osteoblasts’ bone formation ability, however, the point at which this occurs is unknown. The study utilizes a 21-day differentiation process of mesenchymal stem cells. “Window experiments” that vary the intervals of kynurenine treatment to explore its impact at different stages of osteoblast development were utilized. The experimental setup involves four distinct conditions: a control group with a vehicle, a group treated with kynurenine, a group with an AhR antagonist (BAY), and a group treated with both kynurenine and BAY. The AhR antagonist, specifically BAY2416964, serves to investigate whether any observed effects of kynurenine are mediated through AhR signaling. Results, analyzed through alizarin red staining, demonstrate a notable negative impact of kynurenine on matrix production, particularly in the middle stages of osteoblast differentiation. The study further employs crystal violet staining to confirm the presence of cells in the experimental wells, provid-ing assurance of the reliability of the alizarin staining procedure. Importantly, this staining procedure also suggests that the effects of kynurenine on mineralized matrix production are largely independent of any potential impacts on cell viability.

CRANIOMETRICAL CHARACTERISTICS OF THE HUMAN FETAL SKULL

The purpose of the study – to ascertain the regularities of the age-related dynamics ofmorphometric changes of the skull in the fetal period of human ontogenesis.Material and methods. 59 specimens and 12 computed tomography (CT) scans of theskulls of human fetuses aged from 4 to 10 months of intrauterine development (IUD)were studied. A complex of morphological research methods was applied, which includedanthropometry, morphometry, three- dimensional reconstruction and statistical analysis.The results. It has been established that the longitudinal and transverse dimensions, thecircumference of the cerebral part of the skull grow almost uniformly before birth, but bythe 5th month of the IUD, a more accelerated growth is observed, due to which the scatterdiagram has the appearance of a logarithmic dependence. A somewhat uneven growth ofthese morphometric indicators is also observed in the age-related changes in the width andupper height of the face. The growth of the facial angle during the fetal period was revealed,which can be explained by the development of the mandible («pushing» it forward). At the same time, the basilar angle slightly decreases during the fetal period of development,which can be explained by the increase in the brain volume. The basilar angle increaseswith the age of the fetus, but somewhat unevenly in leptins, i. e., until the beginning of the6th month, it almost does not change, during the 6th-7th months it increases intensively,and then slows down again until the end of the fetal period of IUD. In euryons, there isa uniform growth of the basilar angle throughout the fruiting period of development, andmore intensively than in the average morphotype – mesens. Analysis of the correlation offetal age, cranial index, and basilar angle size showed even more significant anatomicalvariability. Thus, if in dolicho- and mesomorphs the basilar angle grows almost uniformlyduring the fetal period, then in brachymorphs it first intensively decreases until the 6thmonth of development, and then begins to grow until the newborn period. It should be notedthat a similar feature is observed in the dynamics of age-related changes in the facial angle,in addition to slowing down its growth from the 8th month in dolichomorphs.Conclusions. 1. Regression analysis of the correlation of age, morphotype indicators, andbasilar and facial angles made it possible to establish patterns of individual morphometricvariability of the skull in the dynamics of the fetal period of prenatal human development,as well as to identify critical periods of morphogenesis of the brain and facial parts ofthe skull, which are 6-7 months in leptins, the 6th month – for brachymorphs and the 8thmonth – for dolichomorphs. 2. The size of the basilar angle of the skull is an importantdiagnostic and prognostic indicator in combination with indices that characterize themorphotype of the individual, for monitoring the normal development of the skull andbrain of the fetus.

Dynamics of strength capabilities of the organism in conditions of ecological and biological well-being

Regular physical activity is of great importance in relation to the formation of all human physical qualities. Differences in the level of strength development within individual sports are recognized. Taking into account this fact, it seems important to study the level of development of strength quality as athletes-athletes grow older. The aim of the study: to evaluate the dynamics of age-related changes in strength abilities in different categories of unicycling athletes. Eighty-one male athletes in adolescence or young adulthood, who regularly trained in judo, hand-tohand combat or Greco-Roman wrestling sections, were studied. A group of adolescents (14 individuals) who had not practiced sports during their lives and a group of non-sports-connected young men (13 individuals) were examined. Hand muscle strength was recorded by hand dynamometry with calculation of Student's t-criterion. During the evaluation of the level of strength in unicycling athletes, it was found that its greatest development was in wrestlers in adolescence and adolescence. In judoists and hand-tohand athletes it was a little less pronounced and comparable. The lowest level of it took place in non-sport-related examinees. As growing up, for all categories under consideration, an increase in strength capabilities in adolescence compared to the level in adolescence was noted.

Age-Related Changes in Blood Plasma Alanine aminotransferase in Partridges (Alectoris Chukar) With the Complex Use of Vitamins and an Antistress Drug

The article presents the results of the influence of vitamins and an anti-stress drug on the biochemical parameters of partridge blood. In order to identify the dynamics of age-related changes in the activity of alanine aminotransferase in the blood of partridges Alectoris chukar with the complex use of vitamins and an anti-stress drug, we conducted studies on 30 partridges during the period of life from 1, 7, 10, 20, 30, 60 to 90 days. Determination of the activity of the enzyme alanine amino transferase in the blood of partridges was carried out on a Specol 1500 spectrophotometer (Analitik Jena) according to the method of R Rej., M Hoder, U.H Bergmeyer at a wavelength of 540 nm [25]. The object of research was the venous blood of partridges. After the inclusion in the daily diet of partridges of a complex of vitamins (A-20000 IU, D3 - 1250 IU, E - 50 mg) and an anti-stress drug (succinic acid) at a dose of 0.05 g per 1 kg of body weight per day, a tendency to improve biochemical indicators of the activity of the enzyme alanyl aminotransferase. Experimentally revealed a decrease in the activity of the enzyme alanyl aminotransferase in the blood of partridges, which were 1.09, 1.17, 1.13, 1.47, 1.44, 1.37 times greater than the indicators of the latter in the control groups of partridges. The activity value of the alanyl aminotransferase enzyme ranged from 0.02 to 0.06 U/ml, with the maximum value reached at 30 days of age.

Peculiarities of age-related morphological changes in the dermal-hair cover of the Pamir yak ecotype bred in the mountain zone of Northern Tajikistan

In the process of animal adaptation to changing environmental conditions, the hair cover, which is known to perform a heat-protective function primarily, plays a significant role. The hair cover of animals undergoes changes depending on the season of the year and the natural and climatic zone in which the animals live. It has its peculiarities in different species (breeds). The nature and features of the hair cover of animals are often used by scientists to compile zoological systematics, assess the health and constitution types of animals, their acclimatisation ability, etc. In this article, the authors reviewed age-related changes in weight, size, thickness and tightness of animal skins (changes in skin thickness from the ridge to the floor) and features of the hair cover of the skin’s yaks of Northern Tajikistan. The authors also noted that in all animals, the weight of hides increases in proportion to the rise in live body weight. The absolute importance of skins, up to the age of half a year of yaks, is almost two times higher than cattle. In yaks at one- and three years old, the thick- ness of skins at the standard point in these animals is somewhat comparable. But the thickness of the pelts in the collar and area of hiding yak next to the floor remains higher by about 25-40%. Yaks are known to have three main categories of hair: long hairs (in the abdominal region of the hide and on the tail), short hairs (on the rump, neck and back) and down inches (in all parts of the animal’s fur). Long coats are also the thickest. The hair length of newborn yaks is 187.60±2.66 mm, of one-year-old yaks 452.50±2.52 mm, and of six-year-old yaks, it reaches 475 mm. The authors determined the total amount of hair of different categories in the three topographic parts of the body: in the rump, the sum of hair is 1545 hair units; in the collar part, the sum of hair is 1590 hair units; in the abdominal area of the body the sum of hair is 1770 hair units. The collar and rump do not have long hairs, unlike the abdomen. Downy hairs are characteristic of all parts of the hide but predominate in the scruff and collar. The dynamics of age-related changes in the hair cover of yaks have been determined.

Dynamic Changes in Lung Microbiota of Broilers in Response to Aging and Ammonia Stress.

Comprehensive microbial analysis has revealed that the lung harbors a complex variety of microbiota, and although the dynamic distribution of the lung microbiota in mice and laying hens of different ages is well established, this distribution has not been clarified in broilers of different ages. Here, we performed 16S rRNA gene sequencing of lung lavage fluid from broilers at 3 (3D), 7 (7D), 14 (14D), 21 (21D), and 35 (35D) days of age to evaluate changes in the composition of their lung microbiota. Upon examination of the composition and function of the broiler lung microbiota, we found that their maturation increased significantly with age. Specifically, the microbiota composition was similar between 7 and 14D and between 21 and 35D. The relative abundance of aerobic bacteria in the broiler lungs gradually increased as the broilers developed, whereas the relative abundance of potentially pathogenic bacteria reached its highest level at 3D. The relative abundance of predicted functions in microbiota was very similar among 3, 7, and 14D, whereas the Glycan Biosynthesis and Metabolism pathway in microbiota was enriched at 21D. These findings suggest that these metabolic pathways play critical roles in shaping broiler microbiota at these age stages. In addition, short-term external ammonia stimulation significantly increased lung inflammation but did not significantly affect the lung microbiota. Taken together, these data reveal the dynamics of age-related changes in the microbiota of broiler lungs and the stability (the significant variation in the microbial composition) of these microbial communities in response to short-term ammonia stress. These findings provide new insights into the development of broiler lung microbiota and serve as a reference for subsequent studies to evaluate disease prevention in broilers subjected to large-scale breeding.

Influence of Social Isolation Stress on Age-Related Changes in Functional Activity and Expression of Receptors of Endogenous Vasoconstrictors in Rat Aorta.

Social isolation stress was modeled by long-term isolation of 12-month-old rats in individual cages over 28 weeks. It was found that sensitization of blood vessels to the vasoconstrictor action of serotonin due to overexpression of 5HT2A-type receptor genes, as well as an imbalance in the expression level of endothelin ETA- and ETB-receptors (55 and 153%, respectively) are the early signs of vascular aging. A significant contribution to the development of age-related changes in the contractile properties of blood vessels is made by the stress component, which is manifested at the level of glucocorticoid-dependent mechanisms of regulation of gene expression. The decrease in the expression of glucocorticoid receptors caused by isolation stress leads to a decrease in the expression of the genes responsible for the synthesis of V1A-R and ATII-R and to the development of vascular hyporeactivity to the vasoconstrictor action of ATII and AVP. In the aorta of stressed rats, the α1-AR mRNA level increases by 3 times. At the same time, stress did not affect the dynamics of age-related changes in the expression of genes encoding 5HT2A-R and ETA/ETB-R.

Динаміка відносного об’єму структурно-функціональних зон паренхіми лімфатичних вузлів бика домашнього (Bos taurus) в ранньому постнатальному онтогенезі

Lymph nodes are peripheral organs of hemo- and lymphopoiesis, their parenchyma is formed by lymphoid tissue and is divided into separate structural and functional lobules, each of which, in turn, is formed by highly and low-specialized cellular zones. The dynamics of age-related changes in the relative volume of the structural and functional zones of the lymph nodes parenchyma lobules in newborn calves of 10-, 30-, 120-day-old was determined. There were examined: superficial cervical, axillary, iliac, popliteal, medial retropharyngeal, caudal mediastinal, medial iliac, iliocolic lymph nodes. The relative volume of the deep cortex central zones units, lymph nodules, interfollicular zone and medullary cords was determined on thin paraffin histosections stained with hematoxylin and eosin. In newborn calves, the lymph nodes lobules were formed, among the structural and functional zones the centers of the deep cortex units were most developed, the relative volume of which was 27–33% and the medullary cords – 21–31%, and the least ones were lymph nodules. The lymph nodules volume without light centers varied within 0.4–1.6%, with light centers – 0.3–1%. The interfollicular zone was 4–11%. During the first ten days of calf life, the greatest growth dynamics was observed in the deep cortex central zones units, the interfollicular zone, and the medullary cords. Until the age of 30 days, the dynamics of an increase in the relative volume of deep cortex units and interfollicular zone stabilized and showed a further tendency of insignificant growth. The most intense increase in the relative volume of lymph nodules was observed in 120-day-old calves. The volume of the medullary cords decreased in all the examined nodes in 30- and 120-day-old calves.

AGE-RELATED CHANGES OF THE PROFILE FIELD OF NEURONS OF THE AREA 7 OF THE BRAIN OF MEN AND WOMEN IN THE PROCESS OF THE AGING

The aim of the work is to study changes in the profile field of pyramidal neurons in the cortex of field 7 of the brain of men and women in the aging process. A cytoarchitectonic study of the cortex of field 7 of the upper parietal region of the brain of men and women was carried out on a series of frontal paraffin sections stained by the Nissl method. The brain preparations of men and women of three age groups were studied: the groups of mature age (from 20 to 60 years), the elderly group (from 60 to 75 years) and the group of senile age (from 75 years and older). In each age group, 5 preparations of the male brain and 5 preparations of the female brain were studied. Age-related changes in the cytoarchitectonics of the profile field of pyramidal neurons in the cytoarchitectonic layers of the third and fifth cortex fields 7 of the brain of men and women were studied. As a result of the study, it was revealed that in the process of aging of the brain of men and women, changes in similar morphometric indicators of field 7 cortex occur at different age periods, the dynamics of age-related changes in functionally different cytoarchitectonic layers III and V of the cerebral cortex of men and women are also different.

Automation of the Diagnosis of Age-Related Changes in Parameters of the Cardiovascular System

An algorithm for calculating the dynamics of age-related changes in parameters of the cardiovascular system of humans in the North of the Russian Federation was developed. Using one coordinate (xi, the cardiac interval) as an example, a method is presented for calculating quasi-attractor parameters in a two-dimensional phase space, where x2 = dxi /dt is the rate of change of cardiac intervals with age. Study results using the algorithm (and the whole automated system) for three age groups of Khanty women to describe age-related changes in quasi-attractor parameters during normal aging are presented.

SEXUAL DIMORPHISM OF HEIGHT-WEIGHT INDICES AND BODY COMPOSITION IN RUSSIAN CHILDREN AND ADOLESCENTS AGED 5–18 YEARS: THE RESULTS OF MASS POPULATION SCREENING

Background: Population screening in Health Centers (HCs) represents the only data source of mass anthropometric and body composition in Russia. Previously, an overview of the physical development and body composition of the population according to HCs’ data along with centile reference tables were published while a detailed analysis of sexual dimorphism was not carried out.Aims: The analysis of sexual dimorphism of height-weight indices and body composition data in modern Russian children and adolescents aged 5–18 years according to HCs data, as well as comparison of the dynamics of age-related changes in anthropometric data with the WHO growth references.Materials and methods: Non-clinical cross-sectional observational study was conducted using bioimpedance and related anthropometric HCs’ data over the period 2010–2012. The data was obtained according to Russian Health Ministry letter no. 14-1/10/2-3200 dated Oct. 24, 2012. The study sample included 268 153 subjects, 140 769 boys and 127 384 girls. Intergroup differences were evaluated with the Mann-Whitney test. The distributions of Ht, Wt, and BMI for age and sex were matched with the WHO reference data using LMS-transformation with the parameters from the WHO expanded tables with the subsequent calculation of 95% confidence intervals for median z-scores.Results: Availability of double crossing of growth curves in boys and girls for Ht and Wt during puberty is shown with a narrower double crossing interval for Wt as compared to conventional data. The relative annual growth rates for Ht and Wt were higher in females up to the age of 12 years, and in males older 12. Throughout the age range, median values of BMI in boys and girls were similar (with the differences in the range of 1 kg/m2); median values of FFM were significantly higher in males, and of BF and %BF in females. In most age groups, the median values of Ht and Wt in Russian children and adolescents were higher as compared to WHO reference data (with the maximal difference z=+0.74 for Wt in 10 years-old boys). The similar pattern was detected for BMI in boys aged 5–17 and girls aged 6–14.Conclusions: The narrower interval of double-crossing of growth curves for Wt may indicate adverse environmental effects associated with overnutrition and reduced physical activity which leads to elevated fatness in boys. Taking into account mass character of data, relatively broad coverage of regions, and the observed differences with the WHO growth references, the use of Health Centers’ data is advisable for the elaboration of the national standard of physical development in children and adolescents.

Chaotic dynamics of cardio intervals in three age groups of indigenous and nonindigenous populations of Ugra

The problem of life expectancy of indigenous and non-indigenous population of northern territories of the Russian Federation is considered in terms of economic growth and industrial development of the northern territories. The importance of prolonging the period of active working age of non-indigenous population of Khanty-Mansi Autonomous Okrug-Ugra and Yamalo-Nenets Autonomous Okrug is increasing. Four directions for possible prolongation of the active life of non-indigenous population were presented. The problem of comparative dynamics of age-related changes of cardiovascular system on three specific age groups of female indigenous and non-indigenous population is being considered. A decrease in volume of quasi-attractors in the phase space of states is equivalent to strengthening of physical activity, which is typical of normal aging. It is proposed to use the mathematical pattern to reduce these volumes in assessing the dynamics of human aging in the North.

Сравнительная характеристика параметров вариабельности сердечного ритма школьников Югры

This article presents a comparative analysis of the parameters of HRV students who are indigenous and non-indigenous residents of Yugra. Analysis was carried out carried out by multiple comparisons of three age subgroups and by multivariate analysis with the calculation of inter-cluster distances. The differences in the dynamics of age-related changes of Yugra schoolchildren reveals distinctive trend parameters of heart rate variability between indigenous and non-indigenous representatives of North. In particular, it revealed a higher adaptive capacity in Aboriginal representatives in comparison with the migrant population. The maximum divergence of parameters of the body boys observed in the older age group.

Age-related differences in auditory cortical representations of spatial cues

Converging evidence indicates that binaural processing declines with age and is impaired further by age-related hearing loss. Research in young, normal-hearing adults indicates that spatial coding is governed by an opponent-channel (OC) mechanism. Under the OC model, the sensitivity to changes or shifts in perceived lateralization can be predicted based on the direction and magnitude of the shift, where large, outward shifts are predicted to cause a greater neural response than small and/or inward shifts. It is possible that age-related changes in spatial coding reflect changes in the OC mechanism, perhaps due to reduced neural inhibition or a more general reduction in temporal precision. Cortical event-related responses elicited by both ITD and ILD changes were measured using a 64-channel montage during a passive, continuous change-detection paradigm. Source localized cortical activation patterns were analyzed with regard to degree of lateralized shift, direction of shift (toward or away from perceived midline), and listener group. Results are consistent with an OC mechanism of spatial coding for both younger and older adults. Behavioral data from the same subjects are reported for correlation analyses with neural data. The present study provides a foundation for understanding the cortical dynamics of age-related changes in spatial tuning.

Dynamics of brain structure and cognitive function in the Alzheimer's disease neuroimaging initiative

BackgroundOn average, cognition declines as people age, but improvement can also occur.ObjectiveTo evaluate the dynamics of age-related changes in brain structure and cognitive function in patients with mild Alzheimer's disease...

Kindling in the early postnatal period: Effects on the dynamics of age-related changes in electrophysiological characteristics of hippocampal neurons

The effects of chronic administration of pentylenetetrazole (PTZ) during early ontogenesis (from postnatal day 14) on the dynamics of age-related changes in electrophysiological characteristics of rat hippocampal slices were studied. Unlike the situation in adult animals, convulsive activity did not develop in rat pups in response to repeated injections. Comparison of the amplitude characteristics of total monosynaptic responses of neurons in hippocampal field CA1 to application of single and paired (separated by 70 msec) stimulation of Schäffer collaterals during the period of maximally intense hippocampal synaptogenesis (at weeks 2-3 of postnatal development) revealed no significant differences between the control group (administration of isotonic saline) and the group given PTZ. The level of suppression of facilitation in paired-pulse stimulation with a short interstimulus interval (15 msec) was significantly less in hippocampal slices from rat pups from the PTZ group. However, as compared with the passive control, the direction of rearrangements in the two experimental group was essentially the same. Nonetheless, regular administration of PTZ during the period of maximally intense hippocampal maturation affected the development of its characteristics. This was not only apparent as a deficiency of inhibitory processes. Increases in the intensity of test stimuli applied to hippocampal slices from PTZ-treated rat pups at 27-48 days of age led to relatively lower response amplitudes as compared with those seen in hippocampal slices from control (given isotonic saline) rats of the same age. The level of facilitation in paired-pulse stimulation with an interstimulus interval of 70 msec showed no difference, decreasing to similar extents in both groups as compared with the passive control group. In addition, hippocampal slices from the PTZ group showed significant decreases in the magnitude of long-term potentiation. Changes occurring in the hippocampus after regular administration of PTZ did not correlate with the development of convulsive activity. The only significant relationship involving the intensity of convulsions was with the increase (compared with the normal for age) in the amplitudes of responses to minimal-intensity test stimuli.

Frequency of micronuclei in the cells of buccal epithelium in Ukrainian schoolchildren of various age and sex

The frequency of micronuclei (MN) has been studied in 266 schoolchildren, participants of All-Ukrainian school competitions on biology and ecology. The distribution of MN frequencies was Poissonian with λ = 2.5. The mean MN frequency was 2.4 ± 0.15‰ in boys and 2.7 ± 0.14‰ in girls; the difference is not statistically significant. The individual MN frequency varied from 0 to 8.3‰ and on the average was 2.5 ± 0.11‰ which does not exceed known mean population values. We have shown differences in the MN frequency between sexes in some age groups: MN frequency was significantly higher in girls than in boys aged 16 years. The dynamics of age-related changes in the MN frequency of boys and girls also differed in the period studied (14–18 years of age).

Immune system aging may be affected by HIV infection: the mathematical model of immunosenescence

In this paper, we analyse the structure of equations in the earlier proposed mathematical model of the dynamics of age-related changes in population of peripheral T lymphocytes. To investigate behaviour of the model solutions in a wide range of values of variables we introduce a linear relation between the rate constants of T lymphocytes proliferation and the values of the mean length of telomeric chromosome fragments spent by naive and memory cells in the course of immune response, as well as the dependence of these parameters on the value of the cell replicative potential. We obtain sufficient conditions for existence, uniqueness, and positiveness of solutions over the whole time interval. The results of numerical calculations illustrate the capabilities of the model for describing accelerated aging mechanisms of the immune system using the example of HIV infection.

Immune system aging may be affected by HIV infection: the mathematical model of immunosenescence

In this paper, we analyse the structure of equations in the earlier proposed mathematical model of the dynamics of age-related changes in population of peripheral T lymphocytes. To investigate behaviour of the model solutions in a wide range of values of variables we introduce a linear relation between the rate constants of T lymphocytes proliferation and the values of the mean length of telomeric chromosome fragments spent by naive and memory cells in the course of immune response, as well as the dependence of these parameters on the value of the cell replicative potential. We obtain sufficient conditions for existence, uniqueness, and positiveness of solutions over the whole time interval. The results of numerical calculations illustrate the capabilities of the model for describing accelerated aging mechanisms of the immune system using the example of HIV infection.