Mitochondria and energetic depression in cell pathophysiology.
Mitochondrial dysfunction is a hallmark of almost all diseases. Acquired or inherited mutations of the mitochondrial genome DNA may give rise to mitochondrial diseases. Another class of disorders, in which mitochondrial impairments are initiated by extramitochondrial factors, includes neurodegenerative diseases and syndromes resulting from typical pathological processes, such as hypoxia/ischemia, inflammation, intoxications, and carcinogenesis. Both classes of diseases lead to cellular energetic depression (CED), which is characterized by decreased cytosolic phosphorylation potential that suppresses the cell's ability to do work and control the intracellular Ca(2+) homeostasis and its redox state. If progressing, CED leads to cell death, whose type is linked to the functional status of the mitochondria. In the case of limited deterioration, when some amounts of ATP can still be generated due to oxidative phosphorylation (OXPHOS), mitochondria launch the apoptotic cell death program by release of cytochrome c. Following pronounced CED, cytoplasmic ATP levels fall below the thresholds required for processing the ATP-dependent apoptotic cascade and the cell dies from necrosis. Both types of death can be grouped together as a mitochondrial cell death (MCD). However, there exist multiple adaptive reactions aimed at protecting cells against CED. In this context, a metabolic shift characterized by suppression of OXPHOS combined with activation of aerobic glycolysis as the main pathway for ATP synthesis (Warburg effect) is of central importance. Whereas this type of adaptation is sufficiently effective to avoid CED and to control the cellular redox state, thereby ensuring the cell survival, it also favors the avoidance of apoptotic cell death. This scenario may underlie uncontrolled cellular proliferation and growth, eventually resulting in carcinogenesis.
Seppet
Enn
E
Department of Pathophysiology, University of Tartu, Tartu, Estonia.
Gruno
Marju
M
Department of Pathophysiology, University of Tartu, Tartu, Estonia.
Peetsalu
Ants
A
Department of Surgery, University of Tartu, Tartu, Estonia.
Gizatullina
Zemfira
Z
KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany.
Nguyen
Huu Phuc
HP
Department of Medical Genetics, University of Tübingen, Tübingen, Germany.
Vielhaber
Stefan
S
Department of Neurology, Otto von Guericke University, Magdeburg, Germany.
Wussling
Manfred H P
MHP
Bernstein Institute for Physiology, Martin-Luther-University Halle-Wittenberg, Germany.
Trumbeckaite
Sonata
S
Institute for Biomedical Research, Kaunas University of Medicine, Kaunas, Lithuania.
Arandarcikaite
Odeta
O
Institute for Biomedical Research, Kaunas University of Medicine, Kaunas, Lithuania.
Jerzembeck
Doreen
D
KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany.
Sonnabend
Maria
M
KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany.
Jegorov
Katharina
K
KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany.
Zierz
Stephan
S
Department of Neurology, Martin-Luther-University Halle-Wittenberg, Germany.
Striggow
Frank
F
KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany.
Gellerich
Frank N
FN
KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany.
D000255:Adenosine Triphosphate / Q000378:metabolism; D017209:Apoptosis / Q000502:physiology; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D004734:Energy Metabolism / Q000235:genetics*; D006019:Glycolysis / Q000502:physiology; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D028361:Mitochondrial Diseases / Q000235:genetics / Q000378:metabolism*; D019636:Neurodegenerative Diseases / Q000235:genetics / Q000378:metabolism*; D010085:Oxidative Phosphorylation
D000255:Adenosine Triphosphate