Leptin Hormone
About Leptin:
Leptin is a hormone produced by fat cells (adipocytes). It directly participates in regulating metabolic processes in the body and also influences the function of some internal endocrine glands. Leptin is also referred to as the “satiety hormone.” In normal conditions, its concentration increases after eating, leading to the synthesis of substances that suppress both physical and psychological appetite.
In cases of congenital leptin deficiency, individuals cease to feel satiated, overeat excessively, and gain weight rapidly. This condition is rare and typically develops in childhood.
Most obese individuals experience an increase in leptin secretion, actively produced by fat cells. However, at the same time, the body tissues cease to respond appropriately to it. This is accompanied by a series of pathological changes in the body, leading to the development of chronic diseases such as type 2 diabetes, coronary artery disease, and heart attacks.
Long-term fasting and/or excessive physical exertion lead to a decrease in leptin levels. This results in disruptions in the function of internal endocrine glands. Cortisol, adrenaline, and somatotropin concentrations increase in the blood, while levels of sex hormones decrease completely. This leads to erectile dysfunction in men, absence of ovulation and menstruation in women, and osteoporosis.
Indications for Testing:
- Weight gain or loss, obesity.
- Cardiovascular diseases.
- Signs of developing diabetes mellitus.
- Delayed sexual development.
- Menstrual irregularities.
- Fertility issues or infertility.
- Suspected genetic hormonal deficiencies.
Study Description:
The enzyme-linked immunosorbent assay (ELISA) method is used to determine leptin levels in the blood. The venous fluid used for analysis is serum.
Preparation for Analysis:
Blood is drawn after an overnight fast. Drinking is restricted to plain water. On the day prior to the analysis, avoid consuming spicy, fatty, and fried foods, and refrain from overeating. One day before the analysis, abstain from alcohol and smoking, and reduce physical and emotional stress an hour before blood collection. If you are taking hormonal medications, it is important to inform the doctor who requested the analysis.
Interpretation of Results:
Measurement unit: ng/mL (nanograms per milliliter).
Reference values:
- Leptin content in the blood depends on the gender and age of the individual studied: In women, leptin levels are always higher due to the stimulating effect of estrogen hormone.
- The table below illustrates the reference values for leptin levels in the blood based on age and gender.
| Age | Normal Range for Women (ng/mL) | Normal Range for Men (ng/mL) |
|---|---|---|
| Less than 3 years | 3.2-3.6 | 2.6-3.0 |
| 3-6 years | 4.8-6.0 | 1.6-2.0 |
| 6-9 years | 14.8-19.2 | 8.6-10.6 |
| 9-12 years | 24.0-28.8 | 13.8-17.4 |
| 12-15 years | 34.0-42.0 | 14.6-17.8 |
| 15-20 years | 32.8-38.0 | 16.8-27.6 |
| Over 25 years | 1.1-27.6 | 0.5-13.8 |
Analytical Result:
Potential reasons for increased leptin levels:
- Overeating.
- Hyperthyroidism.
- Chronic kidney failure.
- Psychological stress.
- Sleep apnea (obstructive sleep apnea).
Potential implications of hormone levels:
- Inadequate food intake, including loss of appetite.
- Excessive consumption of nutrients due to excessive physical exertion.
- Increased levels of thyroid hormones.
- Tuberculosis, psoriasis, autoimmune diseases, and other conditions associated with chronic inflammation.
- Cancerous diseases.
- Chronic sleep deprivation.
It is important to note that hormone levels vary throughout the day, being highest in the morning and evening compared to daytime. When there is a deviation from normal values, additional tests are required to carefully evaluate the patient’s condition, including tests to assess carbohydrate metabolism, lipid metabolism, inflammation, and hormonal balance.