CLIA Leptin

Adiponectin and leptin are among the most important adipokines produced by adipose tissue. These hormones not only act as signaling molecules in energy metabolism but also play a key role in regulating inflammatory processes, insulin sensitivity, and the development of cardiometabolic diseases. Their circulating concentrations and mutual ratio serve as valuable biomarkers for the early detection of metabolic dysfunction and the risk of developing type 2 diabetes or cardiovascular disease.

Leptin – a hormone of energy balance and a marker of leptin resistance
Leptin is produced primarily by white adipose tissue, and its serum levels correlate with total body fat. Its physiological function is to suppress appetite and regulate energy expenditure through the hypothalamus.

However, in obesity, leptin resistance frequently develops, meaning that even very high leptin levels are not effectively utilized by the organism. This condition is associated with:

• impaired central regulation of appetite and satiety,
• increased risk of hypertension (leptin activates the sympathetic nervous system),
• pro-inflammatory effects – leptin stimulates IL-6 and CRP production,
• development of insulin resistance and atherogenesis.

Leptin is also an important immunomodulator; it influences T-lymphocyte proliferation and promotes a pro-inflammatory profile, which explains its role in the low-grade inflammation accompanying metabolic syndrome.

Adiponectin-to-leptin ratio (Adpn/Lep) – a comprehensive marker of adipose tissue function
The Adpn/Lep ratio has emerged as a sensitive indicator of adipose tissue dysfunction and metabolic imbalance. It reflects the balance between the protective and risk-associated effects of adipokines.

• A low Adpn/Lep ratio is associated with leptin resistance, insulin resistance, and an increased risk of metabolic syndrome.
• The Adpn/Lep ratio can identify metabolic risk earlier than conventional clinical markers such as fasting glucose or triglycerides.
• In pediatric populations, it enables early detection of emerging obesity and related metabolic disturbances.
• It supports the personalization of preventive and therapeutic strategies based on an individual’s metabolic profile.

Given their role in the pathogenesis of insulin resistance and atherosclerosis, adiponectin and leptin are increasingly recommended as complementary biomarkers for patients with obesity, prediabetes, and cardiometabolic risk.