Блог

Роль TNF-α (фактора некроза опухоли-альфа) в организме

TNF-α – это провоспалительный цитокин, который играет ключевую роль в:

✔ Иммунной защите – активирует макрофаги и нейтрофилы для борьбы с инфекциями.
✔ Апоптозе – запускает гибель поврежденных или раковых клеток.
✔ Воспалении – усиливает выработку других цитокинов (IL-1, IL-6).
✔ Метаболизме – влияет на инсулинорезистентность и липолиз.
✔ Терморегуляции – вызывает лихорадку при инфекциях.

Симптомы и последствия дисбаланса TNF-α

При избытке (гипервоспаление)

• Острые состояния:
• Сепсис, цитокиновый шторм (шок, полиорганная недостаточность).
• Тяжелые инфекции (COVID-19, туберкулез).
• Хронические болезни:
• Аутоиммунные заболевания (ревматоидный артрит, болезнь Крона).
• Атеросклероз, диабет 2 типа.
• Депрессия, нейродегенерация (болезнь Альцгеймера).

При дефиците (крайне редко)

• Склонность к инфекциям (особенно внутриклеточным, например, туберкулезу).
• Нарушение заживления ран.
• Снижение противоопухолевого иммунитета.

Примечание: Полное отсутствие TNF-α встречается при редких генетических мутациях.

Нормы TNF-α в анализах

Уровень TNF-α измеряется в сыворотке крови методом ИФА. Референсы зависят от лаборатории, но обычно:

Когда назначают анализ?

• Подозрение на сепсис, аутоиммунные заболевания.
• Контроль терапии биологическими препаратами (ингибиторами TNF-α).
• Оценка тяжести COVID-19, ревматоидного артрита.

Что делать при отклонениях?

При высоком TNF-α

1. Медикаментозная терапия:

• Ингибиторы TNF-α (адалимумаб, инфликсимаб – при ревматоидном артрите).
• Кортикостероиды (преднизолон).

1. Натуральные методы:

• Куркумин, омега-3 (снижают воспаление).
• Низкоуглеводная диета (уменьшает инсулинорезистентность).

При низком TNF-α

• Лечение основного иммунодефицита.
• Вакцинация (по показаниям).

Интересные факты

• TNF-α и рак: в низких дозах защищает от опухолей, в высоких – может стимулировать их рост.
• Депрессия: хронически повышенный TNF-α нарушает выработку серотонина.

Вывод

TNF-α – «страж» иммунитета, но при избытке разрушает ткани.
Норма: < 8.1 пг/мл (кровь).
Повышение:

• >15 пг/мл – острое воспаление,
• >50 пг/мл – риск полиорганных осложнений.
  Коррекция: биопрепараты, противовоспалительная диета.

Пример: При ревматоидном артрите уровень TNF-α >20 пг/мл – показание для назначения адалимумаба.

Role of Prolactin in the Body

Prolactin is a hormone produced by the pituitary gland, playing a key role in the reproductive system and beyond.

Main Functions:

1. Lactation – stimulates milk production after childbirth.
2. Reproductive health:

• In women: influences the menstrual cycle, ovulation, and fertility.
• In men: involved in testosterone synthesis and spermatogenesis.

1. Immune regulation – modulates immune cell function.
2. Fluid and electrolyte balance – affects the kidneys (fluid retention).
3. Stress response – prolactin levels rise under stress, anxiety, and physical exertion.

Symptoms of Prolactin Deficiency (Hypoprolactinemia)

Causes:

• Hypopituitarism (pituitary insufficiency due to trauma, surgery, or tumors).
• Use of dopaminergic drugs (levodopa, bromocriptine).

Symptoms:

• In women:
• Inability to breastfeed (lack of milk after childbirth).
• Menstrual irregularities (infrequent periods or amenorrhea).
• In men:
• Reduced libido, infertility (rare).
• General:
• Dry mucous membranes (due to reduced effect on fluid balance).

Important: Prolactin deficiency is rare and usually associated with generalized pituitary dysfunction.

Symptoms of Prolactin Excess (Hyperprolactinemia)

Causes:

• Prolactinoma (benign pituitary tumor).
• Hypothyroidism (elevated TSH stimulates prolactin).
• Medication use (antidepressants, antipsychotics, antiemetics).
• Chronic stress, nipple stimulation, kidney failure.

Symptoms:

• In women:
• Galactorrhea (milk production outside of pregnancy and lactation).
• Menstrual irregularities (oligomenorrhea, amenorrhea).
• Infertility (due to suppressed ovulation).
• Reduced libido, vaginal dryness.
• In men:
• Gynecomastia (breast enlargement).
• Erectile dysfunction, reduced libido.
• Infertility (oligospermia).
• General:
• Headaches, visual disturbances (with macroadenoma).
• Osteoporosis (with prolonged elevation).

Normal Prolactin Levels in Blood Tests

Levels depend on sex, age, and the laboratory.

Reference Values (µIU/L or ng/mL)*:

*Conversion: 1 ng/mL ≈ 21 µIU/L

Important Notes:

• Prolactin is secreted in pulses, peaking at night and in the morning.
• The test should be taken on an empty stomach, in the morning, 2–3 hours after waking.
• Avoid before testing:
• Stress and physical exertion.
• Nipple stimulation, sexual activity.

What to Do if Levels Are Abnormal

If Prolactin is Elevated:

1. Repeat the test (rule out stress or physical exertion).
2. Rule out hypothyroidism (TSH, free T4).
3. MRI of the pituitary gland (if prolactinoma is suspected).
4. Treatment:

• Dopamine agonists (bromocriptine, cabergoline).
• Surgery (for macroadenomas).

If Prolactin is Low:

1. Check other pituitary hormones (TSH, LH, FSH, cortisol).
2. MRI of the pituitary gland (if hypopituitarism is suspected).
3. Replacement therapy (if other hormone deficiencies are present).

Conclusion

• Prolactin is a key hormone for lactation, reproduction, and stress adaptation.
• Excess causes infertility, galactorrhea, and reduced libido.
• Deficiency is rare but dangerous, leading to lack of lactation and hormonal imbalance.
• Normal range:
• Women: 60–500 µIU/L (3–25 ng/mL).
• Men: 60–400 µIU/L (3–20 ng/mL).

Role of TSH (Thyroid-Stimulating Hormone) in the Body

TSH is a pituitary hormone that regulates the thyroid gland via a feedback mechanism.

Main Functions:

1. Stimulation of the thyroid gland – TSH prompts the thyroid to produce T4 and T3.
2. Maintaining hormonal balance – TSH rises when T3/T4 are low and falls when they are high.
3. Controlling metabolism – indirectly affects energy, weight, and body temperature.

Symptoms of TSH Deficiency (Secondary Hypothyroidism)

Causes:

• Damage to the pituitary gland or hypothalamus (tumor, trauma, inflammation).
• Overdose of thyroid hormones (artificial TSH suppression).

Symptoms:

• Fatigue, drowsiness.
• Cold intolerance, dry skin.
• Slow heart rate, constipation.
• Difference from primary hypothyroidism: No goiter; often combined with deficiencies of other pituitary hormones.

Symptoms of Excess TSH (Primary Hypothyroidism)

Causes:

• Autoimmune thyroiditis (Hashimoto’s disease).
• Iodine deficiency.
• Consequences of thyroid surgery.

Symptoms:

• Weight gain, swelling.
• Depression, memory impairment.
• Brittle hair/nails.
• Goiter (enlarged thyroid gland).

Normal TSH Levels in Blood Tests

Important:

• TSH is highest at 2–4 AM and lowest in the evening.
• For borderline values, check free T4 and anti-TPO antibodies.

What to Do if Levels Are Abnormal

If TSH is Elevated:

1. Check free T4 (to confirm hypothyroidism).
2. Test for anti-TPO antibodies (to diagnose Hashimoto’s disease).
3. Start L-thyroxine therapy (dose determined by a doctor).

If TSH is Low:

1. Rule out hyperthyroidism (T3, T4, thyroid ultrasound).
2. If pituitary insufficiency is suspected – perform brain MRI.

Conclusion

TSH is the main «regulator» of the thyroid gland. Its deviations indicate:

• ↑ TSH – underactive thyroid (hypothyroidism).
• ↓ TSH – overactive thyroid or pituitary issues.
  Normal range: 0.4–4.0 mIU/L, but interpretation should always include T4 levels.

Role of DHEA-S (Dehydroepiandrosterone Sulfate) in the Body

DHEA-S is a steroid hormone produced primarily by the adrenal cortex (95%) and, in small amounts, by the ovaries/testes. It is a prohormone, a precursor to testosterone and estrogens.

Main Functions:

1. Source of sex hormones (especially important for women after menopause and for men with age-related decline).
2. Anabolic effects (moderate influence on muscle mass and strength).
3. Neuroprotective and anti-stress effects (reduces anxiety, improves cognitive function).
4. Maintenance of libido (especially in women).
5. Affects immunity (can modulate inflammation).
6. Linked to longevity (its levels decline with age, correlating with the aging process).

Symptoms of DHEA-S Deficiency

Causes:

• Adrenal insufficiency (Addison’s disease).
• Hypopituitarism (low ACTH).
• Age-related decline (levels drop by 2–3% per year after age 30).

Symptoms:

• Chronic fatigue, low energy.
• Decreased libido (especially in women).
• Depression, anxiety.
• Loss of muscle mass and strength.
• Impaired memory and concentration.
• Dry skin, brittle hair.
• Weakened immunity (frequent infections).

Symptoms of Excess DHEA-S

Causes:

• Adrenal tumor (androgen-producing adenoma/carcinoma).
• Congenital adrenal hyperplasia (CAH) – 21-hydroxylase deficiency.
• Polycystic ovary syndrome (PCOS) (in women).

Symptoms in Women:

• Hirsutism (excessive hair growth on the face and body).
• Acne, oily skin.
• Male-pattern baldness (androgenic alopecia).
• Menstrual irregularities (oligomenorrhea, amenorrhea).
• Deepening of the voice.
• Clitoral enlargement.

Symptoms in Men:

• Usually less pronounced (since DHEA-S is weaker than testosterone).
• Possible aggressiveness, acne, early baldness.

In Children:

• Precocious puberty (early hair growth, genital enlargement).

Normal DHEA-S Levels in Blood Tests

Levels depend on sex, age, and the laboratory.

Reference Values (µg/dL):

*Conversion: 1 µg/dL ≈ 0.027 µmol/L

What to Do if Levels Are Abnormal

If DHEA-S is Elevated:

1. Rule out adrenal tumor (CT/MRI scan).
2. Test for CAH (17-OH-progesterone test).
3. In women – rule out PCOS (ovarian ultrasound, testosterone, LH/FSH).

If DHEA-S is Low:

1. Check adrenal function (cortisol, ACTH, aldosterone).
2. DHEA replacement therapy may be considered (only under medical supervision!).

Conclusion

• DHEA-S is an important hormone affecting energy, libido, immunity, and aging.
• Excess leads to androgenic effects (especially in women).
• Deficiency causes fatigue, depression, and decreased libido.
• Normal ranges depend on age and sex; abnormalities require diagnostic investigation.

Important: Do not take DHEA supplements without a doctor’s prescription – they can disrupt your hormonal balance!

The role of cortisol in the body

Cortisol is a stress hormone produced by the adrenal cortex under the control of the hypothalamic-pituitary system ( HPA axis: hypothalamus → ACTH → adrenalglands).

Main functions:

1. Regulation of metabolism:

• Increases the level of glucose in the blood (stimulates gluconeogenesis in the liver).
• Reduces glucose uptake by cells (an insulin antagonist).
• Promotes protein breakdown (catabolic effect).
• It affects lipolysis (fat breakdown).

1. Anti-inflammatory and immunosuppressive effects:

• Suppresses immune responses (used in medicine to treat autoimmune diseases).

1. Stress response:

• Mobilizes the body in critical situations (increases blood pressure, increases heart function).

1. Impact on the central nervous system:

• May cause anxiety, insomnia in excess.

1. Regulation of the water-salt balance:

• Weak mineralocorticoid effect (sodium and water retention).

Symptoms of cortisol deficiency (hypocorticism)

Reasons:

• Addison’s disease (primary adrenal insufficiency).
• Secondary insufficiency (pituitary/hypothalamic problems).
• Abrupt withdrawal of glucocorticoids after prolonged use.

Symptoms:

• Chronic fatigue, weakness.
• Hypoglycemia (dizziness, trembling, sweating).
• Weight loss, decreased appetite.
• Hyperpigmentation of the skin (in Addison’s disease).
• Low blood pressure (hypotension), fainting spells.
• Nausea, vomiting, abdominal pain.
• Depression, irritability.

Acute deficiency (Addison’s crisis) is a dangerous condition!

• Sudden drop in pressure, shock.
• Severe abdominal pain, vomiting.
• Loss of consciousness, possible death.

Symptoms of excess cortisol (hypercorticism)

Reasons:

• Cushing’s disease (pituitary adenoma that secretes ACTH).
• Cushing’s syndrome (a tumor of the adrenal glands or prolonged use of glucocorticoids).
• Functional hypercorticism (chronic stress, obesity, alcoholism).

Symptoms:

• Central obesity (belly fat, thin arms/legs).
• ‘Moon-shaped face’, ‘buffalo hump’ (deposition of fat on the neck).
• Stretch marks (striae) purple color on the stomach, thighs.
• Muscle weakness (due to protein catabolism).
• High blood pressure (hypertension).
• Osteoporosis (frequent fractures).
• Diabetes mellitus (steroid).
• Immune disorders (frequent infections).
• Depression, anxiety, insomnia.
• For women: violation of the cycle, hirsutism.

The norm of cortisol in the blood

Cortisol has a circadian rhythm of secretion:

• Maximum – in the morning (7-9 hours).
• Minimum – in the evening (after 22:00).

Reference values:

Important:

• If a violation is suspected ,a daily salivatest, a daily urine test for cortisol or a desmopressin test are prescribed.
• In Cushing’s syndrome , the morning cortisol may be normal, but it does not decrease in the evening.

What should I do if there are deviations?

• In case of excess: Pituitary/adrenal MRI, ACTH test, dexamethasone test.
• In case of deficiency: ACTH-stimulation test, check of electrolytes (Na↓, K↑).

Treatment:

• Hypercorticism – surgery (removal of the tumor), cortisol synthesis blockers.
• Hypocorticism – lifelong replacement therapy (hydrocortisone).

Vitamin B₆ (pyridoxine) — role, norms and violations

Vitamin B₆ is a group of compounds (pyridoxine, pyridoxal, pyridoxamine) that play a key role in the metabolism of amino acids, the synthesis of neurotransmitters and hemoglobin. The body can’t synthesize it, so it has to come from food.

1. The role of vitamin B₆ in the body

• Protein metabolism -participates in the breakdown and synthesis of amino acids.
• Synthesis of neurotransmitters -serotonin, dopamine, GABA (regulation of mood and sleep).
• Formation of hemoglobin -necessary for the synthesis of heme.
• Immune support -affects the production of antibodies.
• Hormone regulation -helps control levels of estrogen, testosterone, and cortisol.
• Reduction of homocysteine (together with B₉ and B₁₂) – prevention of cardiovascular diseases.

Active form: Pyridoxal-5-phosphate– PLP) — it is its level that is measured in the blood.

2. The norm of vitamin B₆ in the blood

Note:

• In pregnant and elderly people, the need for B₆ increases.
• A PLP level below 20 nmol / L indicates a deficiency.

3. Vitamin B3 Deficiency: causes and symptoms

Causes of the deficit:

• Lack of food – a diet without meat, fish, nuts.
• Alcoholism -disrupts the assimilation of B₆.
• Chronic diseases (kidney failure, celiac disease).
• Medications (isoniazid, oral contraceptives, penicillamine).

Symptoms:

• Dermatitis (peeling of the skin, cracks in the corners of the mouth-cheilosis).
• Glossitis (inflammation of the tongue).
• Microcytic anemia (due to impaired heme synthesis).
• Neurological disorders – depression, confusion, seizures.
• Weakened immune system– frequent infections.

Risk groups:

• Pregnant women (especially with toxicosis).
• People with autoimmune diseases (rheumatoid arthritis).

4. Excess vitamin B₆: is it possible and dangerous?

Overdose of natural B₆ from food is not possible. However , long-term use of high-dose supplements (>100 mg / day) causes:

Symptoms of hypervitaminosis:

• Neuropathy – numbness and tingling in the hands/feet (reversible after withdrawal).
• Photosensitivity – increased sensitivity to light.
• Nausea, heartburn.

Upper limit: 100 mg / day (for adults).

5. Diagnosis and treatment

Analyzes:

1. PLP (pyridoxal-5-phosphate) in plasma is the main marker.
2. Homocysteine (increases with B₆ deficiency).
3. General blood test(anemia, microcytosis).

Deficit management:

• Pyridoxine preparations(10-50 mg / day).
• For neuropathy due to isoniazid – up to 100 mg / day.
• Diet:
• Animal sources: chicken, salmon, liver.
• Vegetable sources: bananas, potatoes, chickpeas, walnuts.

In case of overdose:

• Cancellation of supplements.
• Symptomatic therapy (for example, pain relief for neuropathy).

6. Examples of interpreting results

Important: A B₆ deficiency is often combined with a lack of other B vitamins (especially B₂ and B₃).

Daily consumption rates

• Adults: 1.3-1.7 mg.
• Pregnant women: 1.9 mg.
• Nursing mothers: 2.0 mg.

Toxicity: Prolonged use of >200 mg / day may cause irreversible neuropathy.