Melatonin, a neuroendocrine hormone synthesized by the pineal gland and cholangiocytes, decreases biliary hyperplasia and liver fibrosis during cholestasis-induced biliary injury via melatonin-dependent autocrine signaling through increased biliary arylalkylamine N-acetyltransferase (AANAT) expression and melatonin secretion, downregulation of miR-200b and specific circadian clock genes.
The results showed expression levels of UDP-glucuronosyltransferase 1-1 (UGT1A1), organic anion-transporting polypeptide 1A4 (OATP1A4), multidrug resistance-associated protein 2 (MRP2), multidrug resistance protein 1, sodium-dependent taurocholate cotransporter, and organic anion-transporting polypeptide 1A2 were significantly inhibited in cholestasis rats, which would account for reducing the drug absorption and the metabolic process of YCHD in cholestatic rats.
Induction of the xenobiotic transporter multidrug resistance protein 1 in cholestasis was independent of either PXR or CAR, in contrast to the known pattern of induction of multidrug resistance protein 1 by xenobiotics.
We believe that genetic alterations of alpha-1 antitrypsin and P-glycoprotein, either alone or in association with known pathogenetic mechanisms, may explain the onset of danazol induced cholestasis and justify the difference in its varying duration and intensity.
Reports have described recurrent cholestasis in PFIC2 patients after transplantation, and this has been associated with immunoglobulin G antibodies to BSEP.
The potential mechanism of paeoniflorin in alleviating ANIT-induced cholestasis seems to be related to reduce the over expressions of NF-κB and hepatocyte transporters such as NTCP, BSEP as well as MRP2.
Immunohistochemistry showed a gradual decrease of BSEP from zone 1 to zone 3 of the liver lobule, suggesting that the mutation identified here may predispose patients to cholestasis through a delocalization process of BSEP at the lobular level.(HEPATOLOGY 2013;57:2539-2541).
Serum bile acid profiles of our VPS33B/VIPAS39 mutated patients revealed similar changes to primary defect of bile salt export pump, among which those with isolated cholestasis phenotype had a higher level of total secondary bile acids than that with typical ARC phenotype, indicating the partial residual function of VPS33B.
UDCA, which induced BSEP to increase bile acid-dependent bile flow, aggravated cholestasis and liver injury when the bile duct was obstructed in the acute stage of injury in model mice.
Thus, it has been recognized that while mutations in the gene encoding BSEP are responsible for a subgroup of progressive familial cholestasis (progressive familial intrahepatic cholestasis subtype 2), a pediatric cholestatic disorder that may progress to cirrhosis, defective expression or function of BSEP may underlie some forms of drug-induced cholestasis.
The antibodies were reactive toward the first extracellular loop of BSEP, were of high affinity, and inhibited transport activity of BSEP, thus causing severe cholestasis.
Mutations in BSEP are associated with cholestatic diseases such as progressive familial intrahepatic cholestasis type 2 (PFIC2), benign recurrent intrahepatic cholestasis type 2 (BRIC2), drug-induced cholestasis, and intrahepatic cholestasis of pregnancy.
MYO5B deficiency appears to impair targeting of BSEP to the canalicular membrane with hampered bile acid excretion, resulting in a spectrum of cholestasis without diarrhea.(Hepatology 2017;65:1655-1669).
Children with normal γ-glutamyltransferase cholestasis (n = 47; 13 patients with ATP8B1 deficiency, 19 with ATP-binding cassette, subfamily B (MDR/TAP), member 11 (ABCB11) deficiency, and 15 without either ATP8B1 or ABCB11 mutations) were enrolled.
Six novel mutations (PKHD1: p.Thr777Met, p.Tyr2260Cys; ABCB11: p.Val1112Phe, c.611+1G > A, p.Gly628Trpfs*3 and NPC1: p.Glu391Lys) and two known pathogenic mutations were detected proving our multi gene panel for infantile cholestasis to be a sensitive and specific method overcoming the complexity of the phenotype-based, candidate gene approach.
Our data suggest that the adenovirus-mediated hepatocyte hAQP1 expression improves LPS-induced cholestasis in rats by stimulating the BSEP/ABCB11-mediated biliary bile acid excretion; a finding that might contribute to the understanding and treatment of sepsis-associated cholestatic diseases.