Description

Nori Mouse FGF21 ELISA Kit Summary

Alternative names for FGF21: Fibroblast growth factor 21 (FGF21)

Q9JJN1

Standard Curve

Kit Components
1. Pre-coated 96-well Microplate
2. Biotinylated Detection Antibody
3. Streptavidin-HRP Conjugate
4. Lyophilized Standards
5. TMB One-Step Substrate
6. Stop Solution
7. 20 x PBS
8. Assay Buffer

Other Materials Required but not Provided:
1. Microplate Reader capable of measuring absorption at 450 nm
2. Log-log graph paper or computer and software for ELISA data analysis
3. Precision pipettes (1-1000 µl)
4. Multi-channel pipettes (300 µl)
5. Distilled or deionized water

Protocol Outline
1. Prepare all reagents, samples and standards as instructed in the datasheet.
2. Add 100 µl of Standard or samples to each well and incubate 1 h at RT.
3. Add 100 µl of Working Detection Antibody to each well and incubate 1 h at RT.
4. Add 100 µl of Working Streptavidin-HRP to each well and incubate 20 min at RT.
5. Add 100 µl of Substrate to each well and incubate 5-30 min at RT.
6. Add 50 µl of Stop Solution to each well and read at 450 nm immediately.

Background:

Fibroblast growth factor 21 (FGF21) is a protein that in mammals is encoded by the FGF21 gene^[1] and is a member of the fibroblast growth factor (FGF) family and specifically a member of the endocrine subfamily which includes FGF23 and FGF15/19. FGF21 is the primary endogenous agonist of the FGF21 receptor, which is composed of the co-receptors FGF receptor 1 and β-Klotho.^[2] FGF21 is a hepatokine – i.e., a hormone secreted by the liver where FGF21 expression is regulated by PPARα and levels rise substantially with both fasting and consumption of ketogenic diets. FGF21 regulates simple sugar intake and preferences for sweet foods via signaling through FGF21 receptors in the paraventricular nucleus of the hypothalamus and correlates with reduced dopamine neurotransmission within the nucleus accumbens.^[3] FGF21 stimulates glucose uptake in adipocytes but not in other cell types.^[4] This effect is additive to the activity of insulin. FGF21 is specifically induced by mitochondrial HMGCS2 activity. The oxidized form of ketone bodies (acetoacetate) in a cultured medium also induced FGF21, possibly via a sirtuin 1 (SIRT1)-dependent mechanism.^[5] In cows plasma FGF21 was nearly undetectable in late pregnancy, peaked at parturition, and then stabilized at lower, chronically elevated concentrations during early lactation. Serum FGF-21 levels were significantly increased in patients with type 2 diabetes mellitus (T2DM) which may indicate a role in the pathogenesis of T2DM. Elevated levels also correlate with liver fat content in non-alcoholic fatty liver disease^[6] and positively correlate with BMI in Mouses suggesting obesity as a FGF21-resistant state.

References

1. Nishimura T, et al. (2000). Biochimica et Biophysica Acta. 1492 (1): 203–6.
2. BonDurant LD, Potthoff MJ (2018). Annu Rev Nutr. doi:1146/annurev-nutr-071816-064800.
3. von Holstein-Rathlou S, et al. (2016). Cell Metabolism. 23 (2): 335–43.
4. Kharitonenkov A, et al. (2005). The Journal of Clinical Investigation. 115 (6): 1627–35.
5. Vilà-Brau A, et al. (2011). The Journal of Biological Chemistry. 286 (23): 20423–30.
6. Yan H, et al. (2011). PLOS One. 6 (9): e24895.

Product Citations