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Updated: Jun 1, 2026
11:39
Assessing Autophagic Flux by Measuring LC3, p62, and LAMP1 Co-localization Using Multispectral Imaging Flow Cytometry
Published on: July 21, 2017
Bone cell autophagy is regulated by environmental factors
Adam M Zahm1, Jolene Bohensky, Christopher S Adams
1Children's Hospital of Philadelphia, Philadelphia, PA, USA.
Cells, Tissues, Organs
|May 21, 2011
Summary
Bone cells, or osteocytes, perform autophagy, a cellular recycling process. This process is enhanced by environmental stresses, aiding bone cell survival.
Area of Science:
- Cell Biology
- Bone Biology
- Autophagy Research
Background:
- Osteocytes are crucial for bone maintenance.
- The role of autophagy in osteocyte function remains largely unexplored.
- Understanding cellular stress responses in bone is vital for skeletal health.
Purpose of the Study:
- To investigate if osteocytes exhibit autophagy.
- To determine the regulation of osteocyte autophagy by environmental factors.
- To elucidate the role of autophagy in osteocyte survival under stress.
Main Methods:
- Immunofluorescence staining for microtubule-associated protein light chain 3 (LC3) in murine and human cortical bone.
- Assessment of autophagy in preosteocyte-like MLO-A5 and osteocyte-like MLO-Y4 cells.
- Induction of stress conditions including nutrient deprivation, hypoxia, and calcium stress.
- Analysis of hypoxia-inducible factor 1 (HIF-1) regulation of autophagy.
Main Results:
- Osteocytes in cortical bone show evidence of autophagy (LC3 puncta).
- Basal autophagy is present in MLO-A5 and MLO-Y4 cells.
- Autophagy is upregulated under nutrient deprivation and hypoxia.
- Hypoxia-inducible factor 1 regulates autophagy in response to calcium stress.
- Differentiated MLO-Y4 cells display significant autophagic flux.
Conclusions:
- Osteocytes undergo autophagy.
- Autophagy is regulated by environmental stressors relevant to the bone microenvironment.
- Increased autophagic flux is a survival mechanism for differentiated bone cells facing stress.
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