Page last updated: 2024-10-24

dehydroascorbic acid transport

Definition

Target type: biologicalprocess

The directed movement of dehydroascorbate into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. Dehydroascorbate, 5-(1,2-dihydroxyethyl)furan-2,3,4(5H)-trione, is an oxidized form of vitamin C. [GOC:sl]

Dehydroascorbic acid (DHA), the oxidized form of vitamin C, is transported across biological membranes via specialized transport proteins. The primary transporter responsible for DHA uptake in various tissues, including the liver, kidney, and intestines, is the **sodium-dependent vitamin C transporter 2 (SVCT2)**.

SVCT2 is a transmembrane protein that facilitates the co-transport of DHA with sodium ions. The mechanism involves the following steps:

1. **DHA binds to SVCT2 on the extracellular side of the membrane.** This binding event triggers a conformational change in the transporter, allowing sodium ions to bind to a separate site.

2. **Sodium ions bind to SVCT2.** The simultaneous binding of DHA and sodium ions initiates the transport process.

3. **SVCT2 undergoes a conformational change, translocating DHA and sodium ions across the membrane.** This movement is driven by the electrochemical gradient of sodium ions, which flows down its concentration gradient from the extracellular space to the intracellular compartment.

4. **DHA is released into the intracellular space.** The transporter returns to its original conformation, ready for another transport cycle.

The transport of DHA by SVCT2 is essential for maintaining intracellular vitamin C levels. DHA can be readily converted back to its reduced form, ascorbic acid, by cellular reductases. This process ensures a continuous supply of vitamin C, which is crucial for various biological functions, including collagen synthesis, antioxidant defense, and immune system regulation.

In addition to SVCT2, other transporters may contribute to DHA transport in specific tissues or under specific conditions. For instance, **glucose transporters (GLUTs)**, particularly GLUT1 and GLUT3, have been shown to transport DHA to a lesser extent. However, their role in DHA uptake is generally considered less significant compared to SVCT2.

Furthermore, DHA transport can also be influenced by factors such as pH, temperature, and the presence of other molecules. The precise mechanisms and regulation of DHA transport are still under investigation, but the current understanding highlights the importance of SVCT2 as the primary transporter for this essential nutrient.'
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Proteins (5)

ProteinDefinitionTaxonomy
Solute carrier family 2, facilitated glucose transporter member 1A solute carrier family 2, facilitated glucose transporter member 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P11166]Homo sapiens (human)
Solute carrier family 2, facilitated glucose transporter member 3A solute carrier family 2, facilitated glucose transporter member 3 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P11169]Homo sapiens (human)
Solute carrier family 2, facilitated glucose transporter member 4A solute carrier family 2, facilitated glucose transporter member 4 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P14672]Homo sapiens (human)
Solute carrier family 23 member 1A solute carrier family 23 member 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q9UHI7]Homo sapiens (human)
Solute carrier family 2, facilitated glucose transporter member 2A solute carrier family 2, facilitated glucose transporter member 2 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P11168]Homo sapiens (human)

Compounds (27)

CompoundDefinitionClassesRoles
gossypolGossypol: A dimeric sesquiterpene found in cottonseed (GOSSYPIUM). The (-) isomer is active as a male contraceptive (CONTRACEPTIVE AGENTS, MALE) whereas toxic symptoms are associated with the (+) isomer.
phloretindihydrochalconesantineoplastic agent;
plant metabolite
cytidinecytidinesEscherichia coli metabolite;
human metabolite;
mouse metabolite;
Saccharomyces cerevisiae metabolite
cycloheximidecycloheximide : A dicarboximide that is 4-(2-hydroxyethyl)piperidine-2,6-dione in which one of the hydrogens attached to the carbon bearing the hydroxy group is replaced by a 3,5-dimethyl-2-oxocyclohexyl group. It is an antibiotic produced by the bacterium Streptomyces griseus.

Cycloheximide: Antibiotic substance isolated from streptomycin-producing strains of Streptomyces griseus. It acts by inhibiting elongation during protein synthesis.
antibiotic fungicide;
cyclic ketone;
dicarboximide;
piperidine antibiotic;
piperidones;
secondary alcohol
anticoronaviral agent;
bacterial metabolite;
ferroptosis inhibitor;
neuroprotective agent;
protein synthesis inhibitor
emetineemetine : A pyridoisoquinoline comprising emetam having methoxy substituents at the 6'-, 7'-, 10- and 11-positions. It is an antiprotozoal agent and emetic. It inhibits SARS-CoV2, Zika and Ebola virus replication and displays antimalarial, antineoplastic and antiamoebic properties.

Emetine: The principal alkaloid of ipecac, from the ground roots of Uragoga (or Cephaelis) ipecacuanha or U. acuminata, of the Rubiaceae. It is used as an amebicide in many different preparations and may cause serious cardiac, hepatic, or renal damage and violent diarrhea and vomiting. Emetine inhibits protein synthesis in EUKARYOTIC CELLS but not PROKARYOTIC CELLS.
isoquinoline alkaloid;
pyridoisoquinoline
antiamoebic agent;
anticoronaviral agent;
antiinfective agent;
antimalarial;
antineoplastic agent;
antiprotozoal drug;
antiviral agent;
autophagy inhibitor;
emetic;
expectorant;
plant metabolite;
protein synthesis inhibitor
c 137C 137: RN given refers to parent cpd
imidocarbImidocarb: One of ANTIPROTOZOAL AGENTS used especially against BABESIA in livestock. Toxicity has been reported.ureasantiprotozoal drug
colforsinColforsin: Potent activator of the adenylate cyclase system and the biosynthesis of cyclic AMP. From the plant COLEUS FORSKOHLII. Has antihypertensive, positive inotropic, platelet aggregation inhibitory, and smooth muscle relaxant activities; also lowers intraocular pressure and promotes release of hormones from the pituitary gland.acetate ester;
cyclic ketone;
labdane diterpenoid;
organic heterotricyclic compound;
tertiary alpha-hydroxy ketone;
triol
adenylate cyclase agonist;
anti-HIV agent;
antihypertensive agent;
plant metabolite;
platelet aggregation inhibitor;
protein kinase A agonist
1,1-Dichloro-2,2-bis(4-hydroxyphenyl)ethylenediarylmethane
mmv665852MMV665852: an antischistosomal agent
1,3,4,10-Tetrahydro-9(2H)-acridinoneacridines
anisomycin(-)-anisomycin : An antibiotic isolated from various Streptomyces species. It interferes with protein and DNA synthesis by inhibiting peptidyl transferase or the 80S ribosome system.

Anisomycin: An antibiotic isolated from various Streptomyces species. It interferes with protein and DNA synthesis by inhibiting peptidyl transferase or the 80S ribosome system.
monohydroxypyrrolidine;
organonitrogen heterocyclic antibiotic
anticoronaviral agent;
antimicrobial agent;
antineoplastic agent;
antiparasitic agent;
bacterial metabolite;
DNA synthesis inhibitor;
protein synthesis inhibitor
jp-1302
1,4,8-trimethyl-12-quinolino[2,3-b]quinolinamineaminoquinoline
polysulfide rubber
2-[2-methoxyethyl-(1-oxo-2-thiophen-2-ylethyl)amino]-N-[(4-methoxyphenyl)methyl]-2-(4-propan-2-ylphenyl)acetamidemonoterpenoid
quercetin7-hydroxyflavonol;
pentahydroxyflavone
antibacterial agent;
antineoplastic agent;
antioxidant;
Aurora kinase inhibitor;
chelator;
EC 1.10.99.2 [ribosyldihydronicotinamide dehydrogenase (quinone)] inhibitor;
geroprotector;
phytoestrogen;
plant metabolite;
protein kinase inhibitor;
radical scavenger
kaempferol7-hydroxyflavonol;
flavonols;
tetrahydroxyflavone
antibacterial agent;
geroprotector;
human blood serum metabolite;
human urinary metabolite;
human xenobiotic metabolite;
plant metabolite
genistein7-hydroxyisoflavonesantineoplastic agent;
EC 5.99.1.3 [DNA topoisomerase (ATP-hydrolysing)] inhibitor;
geroprotector;
human urinary metabolite;
phytoestrogen;
plant metabolite;
tyrosine kinase inhibitor
myricetin7-hydroxyflavonol;
hexahydroxyflavone
antineoplastic agent;
antioxidant;
cyclooxygenase 1 inhibitor;
food component;
geroprotector;
hypoglycemic agent;
plant metabolite
cytochalasin bcytochalasin B : An organic heterotricyclic compound, that is a mycotoxin which is cell permeable an an inhibitor of cytoplasmic division by blocking the formation of contractile microfilaments.

Cytochalasin B: A cytotoxic member of the CYTOCHALASINS.
cytochalasin;
lactam;
lactone;
organic heterotricyclic compound
actin polymerisation inhibitor;
metabolite;
mycotoxin;
platelet aggregation inhibitor
pd 166285
pd-173952
glucopiericidin aglucopiericidin A: from Streptomyces pactum S48727 as co-metabolite of piericidin A(1); structure given in first source; glycoside antibiotic
wzb117WZB117: structure in first source
ascorbic acidAscorbic Acid: A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.

L-ascorbate : The L-enantiomer of ascorbate and conjugate base of L-ascorbic acid, arising from selective deprotonation of the 3-hydroxy group. Required for a range of essential metabolic reactions in all animals and plants.

L-ascorbic acid : The L-enantiomer of ascorbic acid and conjugate acid of L-ascorbate.

vitamin C : Any member of a group of vitamers that belong to the chemical structural class called butenolides that exhibit biological activity against vitamin C deficiency in animals. The vitamers include L-ascorbic acid and its salt, ionized and oxidized forms.
ascorbic acid;
vitamin C
coenzyme;
cofactor;
flour treatment agent;
food antioxidant;
food colour retention agent;
geroprotector;
plant metabolite;
skin lightening agent
hesperadin