Reproductive system
The inclusion and deactivation of sexual function are the most important stages, reflecting the essential points of the development program and the onset of aging.
The reproductive system of men undergoes changes as the age increases. From 20 to 40-45 years, there is no significant functional and structural shifts. A decrease in testosterone concentration and an increase in the concentration of gonadotropins in the blood are noted in men from the age of 60, and it is accompanied by a decrease in the number of Leidig cells( in older men their number is 44% compared to the young ones), sperm production and the number of normal spermatozoa. Excretion of 17-CS decreases already from 25-30 years. In men, these changes are moderately expressed, and the capacity for fertilization is maintained. More than 50% of men sperm are produced after 70 years, and in some cases the ability to fertilize is preserved even in extreme old age. Nevertheless, the quality of sperm is deteriorating. The risk of congenital defects in a child from a man older than 40 years increases by 20%.In 70-80 years the testosterone content in the blood is approximately half of its level in 20-50 years, and in 80-90 years - slightly more than a third of this level. There is also a relative increase in the content of estrogens with a change in the ratio of androgens / estrogens.
Given the significant intervals of reference serum testosterone concentrations, most researchers use normal optimal hormone concentrations for comparison for healthy people aged 30-35 years who are 700-900 ng / dl for men, 50-70 ng / dL for women.
With age, the concentration of total and free testosterone in the blood serum decreases, while the content of the SSH increases [Wright J. V., Lenard L., 2000].The CCG is able to bind 3 molecules of free testosterone and thereby block its effects.
The decrease in testosterone concentration with aging and the associated manifestations are now defined as "male menopause" or andropause. Andropause includes the following manifestations.
■ Fatigue.
■ Bad sleep.
■ Reduced muscle mass and strength. Reducing the concentration of testosterone in the blood directly correlates with a decrease in the rate of synthesis of muscle proteins, the formation of contractile structures and muscle strength. Reducing muscle mass correlates with an increased risk of falls and fractures.
■ Increased fat mass, especially in the abdomen and chest, sometimes with gynecomastia. The increase in fat mass is associated with an increase in the concentration of leptin, the peptide hormone of fatty tissue. Its serum level directly correlates with the fat mass. Testosterone concentrations in the blood and muscle mass have an inverse correlation with the level of leptin.
■ Reduced bone mass and density. Age and the associated decrease in testosterone concentration in the blood correlate with loss of bone mass. At 30% of men over the age of 60 years develops osteoporosis.
■ Decreased libido.
■ Erectile dysfunction( decreased potency, decreased ejaculate volume, etc.).
■ Hair loss.
Fig. Dynamics of total and free testosterone and serum concentrations of
Fig. Dynamics of concentrations of total and free testosterone and serum
serum ■ The appearance of wrinkles and dry skin.
■ Reduced memory.
■ Depression.
■ Decreased life activity, apathy.
The decrease in testosterone concentration in the blood is considered a risk factor for such diseases as atherosclerosis, ischemic heart disease, diabetes, arterial hypertension, obesity. An increase in the concentration of glucose, cholesterol, TG, clotting factors and a decrease in coagulation inhibitors largely reflect the decrease in testosterone production with age.
Changes in the reproductive system of women as they age are more significant. The most significant of them are as follows.
■ Increased concentration of FSH 10-20 times, LH - 3 times( reaches a maximum 1-3 years after the onset of menopause);in the future, the content of both gonadotropins in the blood begins to gradually but steadily decrease.
■ The concentration of androstenedione in the blood serum decreases almost 2-fold( its secretion in postmenopause is mainly performed by the adrenal glands).
■ The concentration of testosterone after the onset of menopause is reduced, due to the weakening of the peripheral conversion of androstenedione.
■ The concentration of estradiol in the blood after the onset of menopause is reduced to approximately 10-20 pg / ml.
■ The ratio of androgens / estrogens after menopause changes dramatically towards androgens.
■ There is a decrease in the concentration of DHEA and DHEAS in the blood.
Due to the lack of estrogens, specific problems for this age group are problems associated with the need to prevent osteoporosis, lipid metabolism disorders.