Recovery of the Cholangiocytes After Ischemia and Reperfusion Injury: Ultra-Structural, Hystological and Molecular Assessment in Rats

• Published in: Journal of clinical and experimental hepatology Vol. 8; no. 4; pp. 380 - 389
• Main Authors: Aloia, Thiago P.A., Cogliati, Bruno, Monteiro, Janaina M., Goldberg, Anna C.K., de Oliveira Salvalaggio, Paolo R.
• Format: Journal Article
• Language: English
• Published: India Elsevier B.V 01-12-2018; Elsevier
• Subjects: apoptosis; cholangiocytes; ischemia–reperfusion; Original; rats; AST; PCNA; BIL; VEGF; ALT; apoptosis; I/R; ALKP; CK18; cholangiocytes; GGT; ischemia–reperfusion; LCM; HPC; rats; TEM; ALT, alanine aminotransferase; I/R, ischemia–reperfusion; LCM, laser capture microdissection; HPC, hepatic progenitor cells; VEGF, vascular endothelial growth factor; CK18, cytokeratin-18; TEM, transmission electron microscopy; GGT, gamma-glutamyl transferase; PCNA, proliferating cell nuclear antigen; ALKP, alkaline phosphatase; BIL, bilirubin; AST, aspartate aminotransferase
• ISSN: 0973-6883; 2213-3453
• DOI: 10.1016/j.jceh.2018.01.003

Ischemia–reperfusion (I/R) injury of the liver is a common area of interest to transplant and hepatic surgery. Nevertheless, most of the current knowledge of I/R of the liver derives from the hepatocyte and little is known of what happens to the cholangiocytes. Herein, we assess the sequence of early events involved in the I/R injury of the cholangiocytes.
Sixty Wistar rats were randomized in a SHAM group and I/R group. Serum biochemistry, histopathology, immunohistochemistry, transmission electron microscopy (TEM) and laser capture microdissection (LCM) were used for group comparison.
There was peak of alkaline phosphatase 24h after IR injury, and an increase of aspartate aminotransferase and alanine aminotransferase after 6h of reperfusion, followed by a return to normal levels 24h after injury. The I/R group presented the liver parenchyma with hepatocellular degeneration up to 6h, followed by hepatocellular necrosis at 24h. TEM showed cholangiocyte injury, including a progressive nuclear degeneration and cell membrane rupture, beginning at 6h and peaking at 24h after reperfusion. Cytokeratin-18 and caspase-3-positive areas were observed in the I/R group, peaking at 24-h reperfusion. Anti-apoptotic genes Bcl-2 and Bcl-xl activity were expressed from 6 through 24h after reperfusion. BAX expression showed an increase for 24h.
I/R injury to the cholangiocyte occurs from 6 through 24h after reperfusion and a combination of TEM, immunohistochemistry and LCM allows a better isolation of the cholangiocyte and a proper investigation of the events related to the I/R injury. Apoptosis is certainly involved in the I/R process, particularly mediated by BAX.