Related Experiment Video
Updated: Jun 15, 2025
Co-immunoprecipitation Assay Using Endogenous Nuclear Proteins from Cells Cultured Under Hypoxic Conditions
Published on: August 2, 2018
The Effect of Hypoxia on Irisin Expression in HL-1 Cardiomyocytes
Maciej Grzeszczuk1, Monika Mrozowska2, Alicja Kmiecik2
1Division of Histology and Embryology, Department of Human Morphology and Embryology, Wroclaw Medical University, Wroclaw, Poland; maciej.grzeszczuk@student.umw.edu.pl.
Insights
Hypoxia increases Irisin (Ir) levels in mouse heart cells (HL-1 cardiomyocytes). This finding suggests Ir may serve as a potential biomarker for diagnosing hypoxia and cardiovascular diseases (CVD).
Area of Science:
- Cardiovascular Biology
- Cellular Physiology
- Molecular Medicine
Background:
- Cardiovascular diseases (CVD) are a leading global cause of mortality.
- Irisin (Ir), a glycoprotein crucial for heart function, may act as a biomarker for myocardial infarction.
- Glycosylation influences Ir's stability, solubility, and cellular interactions, impacting its biological functions.
Purpose of the Study:
- To investigate the impact of hypoxia on FNDC5 gene expression and Irisin (Ir) levels in HL-1 cardiomyocytes.
- To determine if Irisin is present and its expression changes under hypoxic conditions in a cardiac cell line.
Main Methods:
- Utilized Real-time PCR (RT-PCR) to quantify FNDC5 gene expression.
- Employed Western blot and immunofluorescence assays to analyze Irisin protein levels.
- Examined the effects of hypoxia on mouse HL-1 cardiomyocytes.
Main Results:
- Hypoxia led to a significant increase in Irisin (Ir) levels within HL-1 cardiomyocytes.
- This study provides the first confirmation of Irisin presence in HL-1 cardiac cells.
- FNDC5 gene expression was also analyzed in response to hypoxic stress.
Conclusions:
- Elevated Irisin expression in cardiomyocytes correlates with hypoxic conditions.
- Irisin shows potential as a diagnostic biomarker for hypoxia and cardiovascular diseases (CVD).
- Further research can explore Irisin's therapeutic potential in cardiac conditions.
Background/Aim:
Cardiovascular diseases (CVD) are the leading cause of death worldwide. In 2019, 523 million people were diagnosed with CVD, with 18.6 million deaths. Improved treatment and diagnostics could reduce CVD's impact. Irisin (Ir) is crucial for heart function and may be a biomarker for heart attack. Ir is a glycoprotein with sugar residues attached to its protein structure. This glycosylation affects Ir stability, solubility, and receptor interactions on target cells. Its secondary structure includes a fibronectin type III domain, essential for its biological functions. Ir helps cardiomyocytes to respond to hypoxia and protects mitochondria. The aim of the study was to determine the FNDC5 gene expression level and the Ir level in HL-1 cardiomyocytes subjected to hypoxia.
Materials And Methods:
We examined the effect of hypoxia on the expression levels of the FNDC5 gene and those of Ir in mouse cardiomyocytes of the HL-1 cell line. Real-time PCR (RT-PCR) was used to estimate the expression levels of the FNDC5 gene. Western blot and immunofluorescence methods were used to analyze the Ir protein levels.
Results:
Analyses showed an increased Ir level in HL-1 cardiomyocytes in response to hypoxia. This is the first study to confirm the presence of Ir in HL-1 cells.
Conclusion:
The observed increase in Ir expression in murine cardiomyocytes is associated with the hypoxic environment and can be potentially used to diagnose hypoxia and CVD.
