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Updated: Oct 17, 2025

In Situ Immunofluorescent Staining of Autophagy in Muscle Stem Cells
Published on: June 12, 2017
Humanin-induced autophagy plays important roles in skeletal muscle function and lifespan extension
Su-Jeong Kim1, Anjali Devgan1, Brendan Miller1
1The Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA.
Background:
Autophagy, a highly conserved homeostatic mechanism, is essential for cell survival. The decline of autophagy function has been implicated in various diseases as well as aging. Although mitochondria play a key role in the autophagy process, whether mitochondrial-derived peptides are involved in this process has not been explored.
Methods:
We developed a high through put screening method to identify potential autophagy inducers among mitochondrial-derived peptides. We used three different cell lines, mice, c.elegans, and a human cohort to validate the observation.
Results:
Humanin, a mitochondrial-derived peptide, increases autophagy and maintains autophagy flux in several cell types. Humanin administration increases the expression of autophagy-related genes and lowers accumulation of harmful misfolded proteins in mice skeletal muscle, suggesting that humanin-induced autophagy potentially contributes to the improved skeletal function. Moreover, autophagy is a critical role in humanin-induced lifespan extension in C. elegans.
Conclusions:
Humanin is an autophagy inducer.
General Significance:
This paper presents a significant, novel discovery regarding the role of the mitochondrial derived peptide humanin in autophagy regulation and as a possible therapeutic target for autophagy in various age-related diseases.
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