cellular response to anoxia

Definition

Target type: biologicalprocess

Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a stimulus indicating a decline in oxygen levels to trace amounts, <0.1%. [GOC:mah]

Cellular response to anoxia is a complex process that involves a cascade of biochemical and physiological events designed to maintain cell survival in the absence of oxygen. Here is a detailed description:

1. **Initial Sensing and Signaling:**
* **Hypoxia-Inducible Factors (HIFs):** When oxygen levels drop, HIFs, particularly HIF-1α, accumulate and activate gene expression, leading to the production of proteins that help the cell cope with oxygen deprivation.
* **Reactive Oxygen Species (ROS):** The lack of oxygen triggers an increase in ROS production, which can activate signaling pathways involved in cellular stress response and damage repair.
2. **Metabolic Adaptations:**
* **Glycolysis:** Cells switch from aerobic respiration to anaerobic glycolysis, producing ATP (energy) at a much lower rate but without the need for oxygen.
* **Glucose Uptake and Utilization:** Glucose uptake increases to fuel glycolysis.
* **Lactate Production:** The end product of anaerobic glycolysis is lactate, which is released from the cell.
3. **Cellular Protection Mechanisms:**
* **Protein Synthesis Reduction:** Protein synthesis slows down to conserve energy.
* **Apoptosis Inhibition:** Initially, the cell attempts to suppress apoptosis (programmed cell death) to prolong survival.
* **Autophagy Induction:** Autophagy, a process where cells break down and recycle their own components, may be activated to provide energy and remove damaged organelles.
4. **Vascular Response:**
* **Vasodilation:** Anoxia can cause vasodilation (widening of blood vessels) in an attempt to increase blood flow and oxygen delivery to the affected area.
5. **Cellular Fate:**
* **Adaptation:** If the anoxic condition is temporary, cells may adapt and survive.
* **Injury and Death:** If the anoxia is prolonged, cells may suffer irreversible damage and die.

The exact response and outcomes of cellular anoxia vary depending on the cell type, the severity and duration of the oxygen deprivation, and the overall health of the organism.'
"

Proteins (1)

Compounds (7)