Autophagyย (orย autophagocytosis) (from theย Ancient Greekย ฮฑแฝฯฯฯฮฑฮณฮฟฯautรณphagos, meaning โself-devouringโ[1]ย andย ฮบฯฯฮฟฯkรฝtos, meaning โhollowโ[2]) is the natural, regulated mechanism of the cell that removes unnecessary or dysfunctional components.[3]ย It allows the orderly degradation and recycling of cellular components.[4][5]
Three forms of autophagy are commonly described:
macroautophagy,
microautophagy, and
chaperone-mediated autophagyย (CMA). In macroautophagy, expendable
cytoplasmicย constituents are targeted and isolated from the rest of the cell within a double-membraned
vesicleย known as anย autophagosome,[6][7]ย which, in time, fuses with an availableย lysosome, bringing its specialty process of waste management and disposal; and eventually the contents of the vesicle (now called anย autolysosome) are degraded and recycled.
In disease, autophagy has been seen as an adaptive response to stress, promoting survival of the cell; but in other cases it appears to promote cell death andย morbidity. In the extreme case of starvation, the breakdown of cellular components promotes cellular survival by maintaining cellular energy levels.
The name โautophagyโ was in existence and frequently used from the middle of the 19th century[8]. In its present usage, the term autophagy was coined by Belgian biochemistย Christian de Duveย in 1963 based on his discovery of the functions of lysosome.[3]ย The identification of autophagy-related genes in yeast in the 1990s allowed researchers to deduce the mechanisms of autophagy,[9][10][11][12][13]ย which eventually led to the award of the 2016ย Nobel Prize in Physiology or Medicineย to Japanese researcherย Yoshinori Ohsumi.[14]
Mandatory FDA Disclaimer: Not intended to diagnose, treat, cure or prevent any disease.
Mandatory FDA Disclaimer: Not intended to diagnose, treat, cure or prevent any disease.
