What does hypoxia-inducible factor do?
Hypoxia-Inducible Factor (HIF)-1 is a dimeric protein complex that plays an integral role in the body’s response to low oxygen concentrations, or hypoxia. HIF-1 is among the primary genes involved in the homeostatic process, which can increase vascularization in hypoxic areas such as localized ischemia and tumors.
How does glomus cell work?
Glomus type I cells are peripheral chemoreceptors which sense the oxygen, carbon dioxide and pH levels of the blood. The glomus cells have a high metabolic rate and good blood perfusion and thus are sensitive to changes in arterial blood gas tension.
Who discovered hypoxia-inducible factor?
In William G. Kaelin, Jr. …to another protein, known as hypoxia-inducible factor (HIF), which stimulates cell proliferation when oxygen is scarce. At normal oxygen levels, VHL binding marks HIF protein for degradation.
How does HIF increase performance?
The target genes of HIF-1 increase oxygen transport through mechanisms such as erythropoietin-mediated erythropoiesis and vascular endothelial growth factor-induced angiogenesis and improve tissue function during low oxygen availability through increased expression of glucose transporters and glycolytic enzymes, which …
What is the function of HIF?
HIF is a transcription factor that plays an essential role in the cellular response to low oxygen, orchestrating a metabolic switch that allows cells to survive in this environment. In immunity, infected and inflamed tissues are often hypoxic, and HIF helps immune cells adapt.
What is a glomus?
Glomus tumors, or paragangliomas, are slow-growing, usually benign tumors in the carotid arteries (major blood vessels in your neck), the middle ear or the area below the middle ear (jugular bulb). Glomus tumors are most often benign; however, they can cause significant damage to surrounding tissues as they grow.
What is a stimulus to the carotid body?
Stimulus. The carotid body peripheral chemoreceptors are primarily sensitive to decreases in the partial pressure of oxygen (PO2). This is in contrast to the central chemoreceptors in the medulla oblongata that are primarily sensitive to changes in pH and PCO2 (a decrease in pH and an increase in PCO2).
How does hypoxia induce erythropoiesis?
In addition to regulating iron metabolism, hypoxia has direct effects on the bone marrow. It promotes erythropoiesis by modulating erythroid progenitor maturation and proliferation. Hypoxia stimulates EPOR expression and regulates components of the hemoglobin synthesis pathway.
How does hypoxia-inducible factors increase performance through angiogenesis?
HAF binds to the ODD in HIF-1α and induces ubiquitination. In contrast, in HIF-2α, HAF binds to the region between the N-TAD and C-TAD and increases HIF-2α activation, thereby inducing a switch from HIF-1α- to HIF-2α-dependent response to chronic hypoxia (28, 74).
What is the HIF pathway?
Abstract. Hypoxia-inducible factor (HIF) is an alpha,beta-heterodimeric transcription factor that mediates cellular responses to low oxygen concentration via the transcriptional activation of specific genes involved in both tumorogenesis and angiogenesis.
How does HIF 1a work?
Per its role in mediating acute responses, HIF1A regulates the activation of glycolytic genes, thereby allowing cells to survive under conditions of decreased oxygen by switching the metabolic scheme from one of oxidative phosphorylation to anaerobic glycolysis.
What is glomus in kidney?
Glomus tumors are rare mesenchymal tumors originating from glomus bodies in the skin. Glomus tumors of the kidney are rare tumors and only a few cases have been reported in the medical literature. An extensive search revealed a very limited number of primary renal glomus tumors.
How are glomus cells affected by hypoxia?
Recent data suggest that carotid body glomus cells from animals raised under hypoxic conditions show blunted electrophysiologic responses to hypoxia compared to cells from healthy animals.
What happens to the glomus cell when PAO2 is decreased?
Oxygen sensing in the carotid body has been localized to the glomus cells but the precise mechanism has been controversial. Decreased PaO2 depolarizes the glomus cell, which increases intracellular calcium (Ca 2+) to cause exocytosis of a neurotransmitter and excitation of the carotid sinus nerve.
What causes a familial glomus cell ( GVM )?
Familial GVM is due to a mutation in the glomulin gene on chromosome 1p21–p22. 138,139 Numerous mutations have been described; they appear to be loss of function mutations. 101,140 Typically GVMs are blue or violaceous lesions which may occur at any site or rarely the mucosa.
How does dopamine affect the function of glomus cells?
The high concentration of dopamine in the glomus cells of the carotid body and the effects of hypoxia on these cells suggest that dopamine is an inhibitory transmitter that modulates the frequency of discharge of the sensory fibers from that structure, which may affect cardiovascular and respiratory responses.