# Galectin-3

Galectin-3 is a small protein (a lectin) released by your activated immune cells (macrophages). It pushes heart fibroblasts to multiply, lay down collagen, and remodel the heart in harmful ways. Labs measure it in blood by an FDA-cleared ELISA or chemiluminescent assay. A multicenter validation (Christenson 2010) set healthy-adult cutoffs of about 17.6, 20.3, and 22.1 ng/mL (the 90th, 95th, and 97.5th percentiles). And de Boer (2011) found levels above 17.8 ng/mL go with higher heart-failure death. Guidelines have cooled on it, though. The 2017 ACC/AHA/HFSA update gave it a weak (Class IIb) recommendation for added risk staging. But the 2022 AHA/ACC/HFSA and 2021 ESC heart-failure guidelines downgraded routine galectin-3 versus natriuretic peptides. So today it is mostly used in research and select cases. Watch the confounders: age (a modest rise), chronic kidney disease (the strongest non-heart driver), lung fibrosis, liver fibrosis, and active cancer. And because assays differ, track it on the same platform.

## Sources

- Christenson RH, Duh SH, Wu AHB, Smith A, Abel G, et al.. (2010). Multi-center determination of galectin-3 assay performance characteristics: anatomy of a novel assay for use in heart failure. Clinical Biochemistry. https://doi.org/10.1016/j.clinbiochem.2010.02.001
- Yancy CW, Jessup M, Bozkurt B, et al.. (2017). 2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure. Journal of the American College of Cardiology. https://doi.org/10.1016/j.jacc.2017.04.025
- Heidenreich PA, Bozkurt B, Aguilar D, et al.. (2022). 2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure. Circulation. https://doi.org/10.1161/CIR.0000000000001063
- de Boer RA, Voors AA, Muntendam P, van Gilst WH, van Veldhuisen DJ. (2009). Galectin-3, cardiac function, and fibrosis. American Journal of Pathology. https://doi.org/10.2353/ajpath.2010.090563

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_Canonical: https://longevity-germany.com/en/glossary/galectin-3 · Part of Longevity Cities · Updated 2026-06-22_