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Despite the fact, that osteoporosis is a disease of the and growth factors. In conditions of estrogen deficiency, T
older population, its significance is often overlooked when cells accelerate the recruitment of osteoclasts, inhibit the-
considering the health of older women. It should not be ir differentiation, and influence the prolongation of their
forgotten that osteopenia, a precursor to osteoporosis, is a lifespan through interleukin 1, interleukin 6, and tumor
condition resulting from menopause that can be prevented. necrosis factor-alpha. Additionally, T cells cause premature
apoptosis of osteoblasts through interleukin 7. In conditi-
The reduction in bone mass occurs due to bone resorpti- ons of estrogen deficiency, bones are more sensitive to the
on, which is the result of accelerated bone breakdown while effects of parathyroid hormone.
bone formation levels are maintained within premenopau-
sal ranges. In postmenopause, bone resorption is about Calcium deficiency - Calcium, vitamin D, and parat-
20% faster compared to younger ages . hyroid hormone maintain bone homeostasis. If the diet
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is low in calcium or if there is reduced calcium absorption
The World Health Organization uses bone density, me- due to aging or the presence of certain diseases, secondary
asured through DXA scans, as a criterion for bone health, hyperparathyroidism may occur, leading to increased calci-
expressed in terms of T-scores or Z-scores. The T-score re- um absorption from the bones and reduced calcium excreti-
presents bone density compared to the bone density of on through the kidneys.
control subjects at their peak bone mass, while the Z-score
compares the bone density of patients with individuals of Vitamin D deficiency - Vitamin D controls the concen-
similar gender and age. tration of calcium and phosphate, which are necessary for
healthy bones and teeth. Besides maintaining bone density,
The diagnostic classification recommended by the Wor- this important biogenic element is believed to play a role
ld Health Organization applies to postmenopausal women in preventing cardiovascular, inflammatory, and malignant
and men over 50 years old. According to this classification, diseases. There are two ways to obtain vitamin D - throu-
osteoporosis is defined as bone mineral density equal to gh synthesis in the skin and dietary intake. We intake vi-
or less than 2.5 standard deviations below the peak bone tamin D2, through food (ergocalciferol), which is of plant
mass. Osteopenia is defined as bone mineral density 1.0- origin, and vitamin D3 (cholecalciferol), which is of animal
2.49 standard deviations below the T-score 18-20 . origin. However, the main source of vitamin D is the synt-
hesis of vitamin D3 in the skin under the influence of UVB
rays. The primary function of vitamin D is to regulate cal-
Pathophysiological events cium absorption from the intestine and stimulate calcium
in osteoporosis resorption from bones to maintain serum calcium levels. In

The genesis of osteoporosis lies in the imbalance conditions of vitamin D deficiency, calcium absorption from
between bone resorption and formation. In physiological the intestine decreases, and the production of osteoclasts
conditions, bone resorption and formation are balanced. increases, which mobilize calcium from bones. Due to ina-
Osteoporosis occurs when this balance is disrupted – either dequate intake, vitamin D interacts with receptors on osteo-
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due to accelerated resorption or decreased formation. It's blasts, leading to increased osteoclast formation .
important to note that osteoporosis can result from redu- Biochemical markers of bone metabolism - We distin-
ced bone formation throughout life and failure to achieve guish markers of bone formation and markers of bone re-
peak bone density at younger age. The two main factors for sorption. Markers of bone formation include: total and
osteoporosis are aging and loss of gonadal function. Pos- bone-specific alkaline phosphatase (serum), osteocalcin (se-
tmenopausal osteoporosis is primarily due to estrogen de- rum), C- and N-terminal propeptides of type 1 procollagen,
ficiency, while senile osteoporosis is mainly associated with PICP, PINP (serum), and other non-collagenous bone prote-
aging. ins. Markers of bone resorption include: tartrate-resistant
acid phosphatase (plasma), calcium (urine), hydroxyproline
In the aging process, after the age of 30, bone resorpti-
on surpasses bone formation, which can later lead to oste- (urine), pyridinium crosslinks (urine), collagen type 1 telo-
openia/osteoporosis. Women lose about 40% of cortical peptide beta crosslaps (urine, serum), C-terminal telopepti-
bone, while men lose about 15-20%. Additionally, women de of type 1 collagen (ICTP - serum), NTX (urine). The bone
experience a loss of about 50% of trabecular bone, while turnover index represents the relative value of the osteoca-
men have a loss of about 25-30%. Age-related bone loss is lcin and crosslaps ratio (osteocalcin/crosslaps x 1,000). The
characterized by decreased osteoblast supply relative to de- bone turnover index examines the degree of deviation from
mand, whereas bone loss in postmenopause is characteri- the ratio of physiological bone remodeling processes (bone
zed by increased osteoclast activity . formation and bone resorption) from the ideal equilibrium
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state. The value of the index in a healthy population is aro-
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Estrogen deficiency - Causes a decrease in bone densi- und 90 .
ty in women as well as in men because osteoblasts, osteoc-
lasts, and osteocytes have estrogen receptors. On the other
hand, estrogen indirectly affects bone through cytokines

REVIEW PAPER Galenika Medical Journal, 2024; 3(9):62-68. 65