FGF21 - Fibroblast Growth Factor 21 | Elisa - Clia - Antibody - Protein

Background:

Fibroblast Growth Factor 21, or FGF21, is a protein that plays a significant role in various metabolic processes. FGF21 is involved in the regulation of glucose and lipid metabolism, making it a key player in energy homeostasis. It can promote energy expenditure and has been studied for its potential role in fighting obesity.FGF21 also enhances insulin sensitivity, which is beneficial for individuals with insulin resistance or type 2 diabetes.FGF21 is mainly produced in the liver, although it can also be produced in other tissues, including fat tissue and the pancreas. Its production is influenced by various factors such as fasting, ketogenic diets, and certain hormones. Due to its roles in metabolism and insulin sensitivity, FGF21 has been studied extensively for its potential as a therapeutic target for obesity and type 2 diabetes. FGF21 analogs have been developed as potential drugs for metabolic diseases. FGF21 has been referred to as a "caloric restriction mimetic" because its effects on metabolism mimic some of the benefits seen in calorie-restricted diets. Several FGF21 analogs have been developed for research and potential therapeutic use. These analogs are designed to mimic the effects of natural FGF21 but with improved stability and pharmacokinetics.

Protein Structure:

FGF21 is a peptide hormone consisting of 209 amino acids in humans. Its structure features:

• N-terminal signal peptide: Facilitates secretion into the extracellular space.
• Core FGF domain: Characteristic of the FGF family, involved in receptor binding and activation.
• C-terminal region: Important for biological activity and stability.

FGF21 has a unique sequence compared to other FGFs, contributing to its distinct biological functions. It does not have heparin-binding domains, differentiating it from many other FGFs.

Classification and Subtypes:

FGF21 is part of the FGF19 subfamily, which also includes FGF19 and FGF23. These FGFs are endocrine FGFs, meaning they function as hormones that circulate in the bloodstream to exert effects on distant organs.

Function and Biological Significance:

• Metabolic Regulation: FGF21 plays a critical role in regulating glucose and lipid metabolism. It enhances insulin sensitivity, promotes glucose uptake, and inhibits lipogenesis.
• Energy Homeostasis: It influences energy expenditure and has been shown to increase fatty acid oxidation and ketogenesis, particularly during fasting and starvation.
• Body Weight Management: FGF21 has anorectic effects, reducing food intake and contributing to weight loss in animal models.
• Liver Function: It is primarily produced in the liver and acts on multiple tissues, including the liver, adipose tissue, and brain, to coordinate metabolic responses.

Interactions:

• FGFRs and β-Klotho: FGF21 signals through fibroblast growth factor receptors (FGFR1c, FGFR2c, and FGFR3c) in the presence of the co-receptor β-Klotho. This complex formation is essential for FGF21's biological activity.
• Adiponectin: FGF21 enhances the secretion of adiponectin, an insulin-sensitizing adipokine, which contributes to its beneficial metabolic effects.

Clinical Issues:Clinical Issues:

• Metabolic Diseases: Due to its role in improving insulin sensitivity and lipid profiles, FGF21 is being investigated as a therapeutic agent for type 2 diabetes, obesity, and non-alcoholic fatty liver disease (NAFLD).
• Cardiovascular Health: FGF21 has cardioprotective effects and may reduce the risk of cardiovascular diseases associated with metabolic syndrome.
• Longevity and Aging: Studies suggest that FGF21 might play a role in extending lifespan and improving healthspan, potentially by mimicking the effects of caloric restriction.

Summary:

FGF21 is a metabolic regulator with significant effects on glucose and lipid metabolism, energy homeostasis, and insulin sensitivity. By interacting with FGFRs and β-Klotho, FGF21 exerts endocrine functions that make it a promising therapeutic target for metabolic diseases. Its ability to enhance adiponectin levels and promote beneficial metabolic changes positions FGF21 as a key player in the management of conditions like diabetes, obesity, and NAFLD. Further research is ongoing to fully understand its mechanisms and potential clinical applications.