What does MDR3 do?
MDR3 mediates the secretion of phosphatidylcholine into bile. Under normal conditions, secreted phosphatidylcholine complexes with bile salts to form mixed micelles, thereby protecting the biliary epithelium from the detergent action of secreted bile salts.
What is MDR3 deficiency?
MDR3 deficiency is a rare genetic disorder that predominantly affects the liver. The disorder represents a spectrum of diseases that can range from mild to severe. The main symptom is interruption or suppression of the flow of bile from the liver (cholestasis).
Is cholestatic liver disease serious?
Cholestatic liver diseases result from gradual destruction of bile ducts, accumulation of bile acids and self-perpetuation of the inflammatory process leading to damage to cholangiocytes and hepatocytes. If left untreated, cholestasis will lead to fibrosis, biliary cirrhosis, and ultimately end-stage liver disease.
Is cholestasis serious?
There is a serious risk of complications in your developing baby if you have cholestasis of pregnancy. The complications include: Fetal distress. This means your developing baby is not doing well.
What enzyme deficiency can cause gallstones?
Additional symptoms that may affect individuals with MDR3 deficiency include the development of gallstones. Gallstones, also known as cholelithiasis, can cause obstruction and/or inflammation of the gallbladder (cholecystitis), which can result in cramping pain in the upper abdomen, fever and jaundice.
What causes cholestatic liver disease?
Intrahepatic cholestasis occurs in certain instances of viral, alcoholic, drug-induced, and chronic liver diseases, such as genetic defects[2] (Table 1). Gallstones, bile duct strictures, and tumours are the most frequent causes of extrahepatic (mechanical) bile duct obstruction[2] (Table 1).
What does MDR3 do in the liver?
Among them, MDR3 is responsible for the secretion of phospholipids from hepatocytes into bile. It is almost exclusively expressed in the liver, with much lower mRNA expression levels in the adrenal gland, muscle, tonsil, spleen, placenta, testis, and ileum.
MDR3 deficiency is a rare genetic disorder that predominantly affects the liver. The disorder represents a spectrum of diseases that can range from mild to severe. The main symptom is interruption or suppression of the flow of bile from the liver (cholestasis).
What is the pathophysiology of MDR3 deficiency with cholestasis?
Cholestasis in MDR3 deficiency occurs due to defects within the liver (intrahepatic), although the defects can also lead to injury of the bile ducts outside the liver (extrahepatic).
Is the MDR3 transporter a floppase?
The MDR3 transporter, a ~140 kDa protein, has been predicted to be a floppase that translocates phosphatidylcholine (PC) from the inner to the outer leaflet of the canalicular membrane bilayer.