Glycogen autophagy

Kotoulas, Othon B.; Kalamidas, Stefanos A.; Kondomerkos, Dimitrios J.

doi:10.1002/jemt.20046

Cited by 71 publications

(70 citation statements)

References 143 publications

(180 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Hypoglycemia has long been thought to induce lysosomal degradation of glycogen in liver in the immediate postnatal period of starvation. 39,40 On the other hand, the neonatal pattern of starvation-induced autophagy does not include liver, 38 and the role for hepatic glycogen autophagy in the early postnatal period has been challenged by data from autophagy deficient mice: neonates appear to depend on the amino acids produced by autophagy rather than on glucose supply for energy homeostasis and survival. 37 In this study, undifferentiated human myoblasts, multinucleated myotubes, and muscle fibers showed very different levels of basal autophagic activity.…”

Section: Discussionmentioning

confidence: 99%

Deconstructing Pompe Disease by Analyzing Single Muscle Fibers: “To See a World in a Grain of Sand…”

Raben¹,

Takikita²,

Pittis³

et al. 2007

Autophagy

100

View full text Add to dashboard Cite

Autophagy is a major pathway for delivery of proteins and organelles to lysosomes where they are degraded and recycled. We have previously shown excessive autophagy in a mouse model of Pompe disease (glycogen storage disease type II), a devastating myopathy caused by a deficiency of the glycogen-degrading lysosomal enzyme acid a-glucosidase. The autophagic buildup constituted a major pathological component in skeletal muscle and interfered with delivery of the therapeutic enzyme. To assess the role of autophagy in the pathogenesis of the human disease, we have analyzed vesicles of the lysosomal-degradative pathway in isolated single muscle fibers from Pompe patients. Human myofibers showed abundant autophagosome formation and areas of autophagic buildup of a wide range of sizes. In patients, as in the mouse model, the enormous autophagic buildup causes greater skeletal muscle damage than the enlarged, glycogenfilled lysosomes outside the autophagic regions. Clearing or preventing autophagic buildup seems, therefore, a necessary target of Pompe disease therapy.

show abstract

Section: Discussionmentioning

confidence: 99%

Deconstructing Pompe Disease by Analyzing Single Muscle Fibers: “To See a World in a Grain of Sand…”

Raben¹,

Takikita²,

Pittis³

et al. 2007

Autophagy

100

View full text Add to dashboard Cite

show abstract

“…Indeed, Atg5-deficient mice have increased AMPK activation in the heart, suggesting a shortage in ATP production. 51 However, gluconeogenic mechanisms are not fully established in the newborn, 53 and they may need a direct supply of glucose. Degradation of glycogen could meet this demand.…”

Section: Effect Of Energy Level and Ampk In Autophagy Induction In Hementioning

confidence: 99%

“…Autophagic degradation of glycogen in the newborn liver has long been recognized as an important survival mechanism for the newborn to adapt to the postnatal environment. 53 Glycogen autophagy is likely stimulated by glucagon, which is secreted in response to hypoglycemia normally occurring in the newborn. In newborn hepatocytes, most of the autophagosomes are spatially and functionally related to glycogen, appearing at the borders of glycogen stores and usually containing various amounts of glycogen.…”

Section: Effect Of Energy Level and Ampk In Autophagy Induction In Hementioning

confidence: 99%

“…It can thus be stimulated by glucagon, cAMP, ␤-adrenergic agonists, or rapamycin but suppressed by ␤-antagonists or insulin. 53 Uniquely, glycogen autophagy could be suppressed by parenteral glucose. It is not clear how the relative selectivity of glycogen degradation versus protein degradation under the same hormonal regulation is achieved.…”

Section: Effect Of Energy Level and Ampk In Autophagy Induction In Hementioning

confidence: 99%

See 1 more Smart Citation

Autophagy in the liver

2008

View full text Add to dashboard Cite

A great part of our current understanding of mammalian macroautophagy is derived from studies of the liver. The term "autophagy" was introduced by Christian de Duve in part based on ultrastructural changes in rat liver following glucagon injection. Subsequent morphological, biochemical, and kinetics studies of autophagy in the liver defined the basic process of autophagosome formation, maturation, and degradation and the regulation of autophagy by hormones, phosphoinositide 3-kinases, and mammalian target of rapamycin. It is now clear that macroautophagy in the liver is important for the balance of energy and nutrients for basic cell functions, the removal of misfolded proteins resulting from genetic mutations or pathophysiological stimulations, and the turnover of major subcellular organelles such as mitochondria, endoplasmic reticulum, and peroxisomes under both normal and pathophysiological conditions. Disturbance of autophagy function in the liver could thus have a major impact on liver physiology and liver disease. (HEPATOLOGY 2008;47: 1773-1785.)

show abstract

“…49 In the newborn also, provision of glucose by glycogen degradation is an important role of autophagy until provision of nutrients by milk takes place. 50 …”

Section: Autophagy In Maintenance Of Homeostasis In Liver and Hepaticmentioning

confidence: 99%

Autophagy Modulation As a Potential Therapeutic Target for Liver Diseases

Puri

Chandra

2014

Journal of Clinical and Experimental Hepatology

View full text Add to dashboard Cite

Autophagy is a critical intracellular pathway which maintains cellular function by lysosomal degradation of damaged proteins and organelles besides elimination of invading pathogens. Its primary function is to prevent cell death. Autophagy has diverse physiological functions namely; starvation adaptation, prevention of tumorigenesis, energy homeostasis, intracellular quality control and degradation of abnormal intracellular protein aggregates. Understanding the molecular mechanisms of autophagy has given key insights into the pathogenesis of various diseases like Non Alcoholic Steato-Hepatitis, Hepatitis B and C infections, Alpha-1 antitrypsin deficiency and hepatocellular carcinoma. Pharmacological modulation of autophagy may have a therapeutic potential in management of these liver diseases. ( J CLIN EXP HEPATOL 2014;4:51-59) O urobros or Urobros is an ancient symbol depicting a serpent or a dragon eating its own tail, which symbolizes cyclicality in the sense of something recreating itself. In living organisms, cells and intracellular organelles need to be constantly remodeled and renewed. Autophagy is a term derived from Greek terminology for self-eating and signifies the process of cellular selfdigestion in which cytoplasmic components are degraded in lysosomes. Reminiscent of the serpent eating its own tail in the symbol of Ourobros, the cells are able to survive by using autophagy to remove damaged proteins and organelles, eliminate invading microbes and generate nutrients during starvation.After Metchnicoff, a Russian zoologist, first described phagocytosis, the role of lysosomes and autophagy in degrading cytoplasmic components has been elucidated. 1,2 The control of autophagy has been recently delineated by identification of over 30 Autophagy-related (ATG) genes. 3 Autophagy functions to prevent rather than promote cell death. Autophagy has effects of increased cytoprotection, decreased stem cell attrition, decreased oncogenic transformation, decreased dysfunctional mitochondria and decrease in dysfunctional aggregate prone proteins. 4

show abstract

Glycogen autophagy

Cited by 71 publications

References 143 publications

Deconstructing Pompe Disease by Analyzing Single Muscle Fibers: “To See a World in a Grain of Sand…”

Deconstructing Pompe Disease by Analyzing Single Muscle Fibers: “To See a World in a Grain of Sand…”

Autophagy in the liver

Autophagy Modulation As a Potential Therapeutic Target for Liver Diseases

Contact Info

Product

Resources

About