Description

Nori Human Asprosin ELISA Kit Summary

Alternative names for asprosn: Fibrillin, fibrillin-1

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: 

Asprosin also known as fibrillin, is a protein hormone produced by mammals in their fatty (white adipose) tissues that stimulates the liver to release glucose into the blood stream. In these tissues, asprosin is encoded by the gene FBN1.^[1] In the liver, asprosin activates rapid glucose release via a cyclic adenosine monophosphate (cAMP) dependent pathway. It is transported to the liver, where it stimulates the release of glucose into the blood stream, via a cAMP-dependent pathway. Glucose released by the liver into the blood stream is required for the normal function of the brain and other organs, as well as for survival during fasting and other aspects of mammalian function. Individuals with Marfanoid–progeroid–lipodystrophy syndrome (MPL) are deficient in asprosin, while people presenting the condition of insulin resistance and obesity produce it in abundance. Dr. Atul Chopra and coworkers found mutations in the FBN1 gene in two patients with congenital partial lipodystrophy and a progeroid appearance. The two patients were Lizzie Velasquez and Abby Solomon. Truncations of the FBN1 protein in these patients were seen to have two consequences for protein production: a mutant/truncated fibrillin protein and very low plasma asprosin levels (from a postulated dominant negative effect). The condition has since been named Marfanoid–progeroid–lipodystrophy syndrome. In addition to performing a glucogenic function, asprosin is a centrally acting orexigenic hormone that is a potential therapeutic target in the treatment of both obesity and diabetes.^[2]  Absence of the C-terminal cleavage product of profibrillin (encoded by FBN1) in humans results in a unique pattern of metabolic dysregulation that includes partial lipodystrophy, accompanied by reduced plasma insulin, while maintaining euglycemia.^[3] Progressive pathological aortic root enlargement as the result of degeneration of microfibril architecture and

consequential loss of extracellular matrix integrity due to fibrillin-1 (FBN1) mutations are commonly diagnosed clinical manifestations of MFS.^[4]

References

1. Maslen CL, et al. (1991) Nature 352 (6333), 334-337
2. Duerrschmid C, et al. (2017) Nat. Med. 23 (12), 1444-1453
3. Romere C, et al. (2016) Cell 165 (3), 566-579
4. Ramachandra CJ, et al. (2015) Int. J. Cardiol. 187, 585-591.

Product Citations