Human Intact FGF-21 ELISA

Fibroblast Growth Factor 21 (FGF-21) belongs to the FGF-19 subfamily, which includes FGF-19, FGF-21, and FGF-23. The FGF-19 family members are potent endocrine hormones in the regulation of physiological homeostasis. Intact FGF-21 is a small protein comprised of 181 amino acids. Administration of recombinant FGF-21 lowered plasma glucose and insulin levels, reduced hepatic and circulating triglycerides and cholesterol levels, and improved insulin sensitivity, energy expenditure, hepatic steatosis and obesity in a range of insulin-resistant animal models. The physiological functions of FGF-21 rely on the intact molecular structure and amino acid sequence in its N-terminal and C-terminal region. The N-terminal truncated FGF-21 (7-181) is a potent inhibitor that competitively inhibits the biological activity of intact FGF-21 (1-181). Therefore, it is important to measure the circulating intact FGF-21 level in the assessment of the physiological and pathophysiological condition. An assay that cross-reacts with the fragment of the FGF-21 might overestimate the biological activity of the protein in test samples. Measuring FGF-21 can be used in researching nonalcoholic fatty liver disease (NFALD), type 2 diabetes, Cushing syndrome, and kidney disease.