title: Calcium-sensing receptors induce apoptosis during simulated ischaemia-reperfusion in Buffalo rat liver cells.
abstract: 1. Calcium-sensing receptors (CaSR) exist in a variety of tissues. In 2010, we first identified its functional expression in Buffalo rat liver (BRL) cells and demonstrated that the activation of CaSR was involved in an increased intracellular calcium through the Gq subunit-phospholipase C-inositol triphosphate pathway. However, its role and related mechanism in hepatic ischaemia/reperfusion (I/R) injury is still unclear. 2. Therefore, in the present study, BRL cells were incubated in ischaemia-mimetic solution for 4 h, then reincubated in the normal culture medium for 10 h to establish a simulated I/R model. We assayed the apoptotic ratio of BRL cells by flow cytometry and Hoechst 33342 staining; analyzed the expression of CaSR, cytochrome c (Cyt-c), caspase-3, Bcl-2, Bax, extracellular signal-regulated protein kinase (ERK), and p38 by Western blotting; and measured the concentration of intracellular calcium by laser-scanning confocal microscopy. 3. The results showed that simulated I/R increased the expression of CaSR and induced apoptosis in BRL cells. GdCl(3), a specific activator of CaSR, further increased CaSR expression, intracellular calcium, and apoptosis in BRL cells during I/R. The activation of CaSR downregulated Bcl-2 expression, upregulated Cyt-c, caspase-3, and Bax expressions, and promoted p38 and ERK-1/2 phosphorylation. 4. In conclusion, increased CaSR expression plays a vital role in apoptosis induced by I/R injury, in which its mechanism is related with calcium overload and the activation of the mitochondrial and mitogen-activated protein kinase apoptotic pathways. The regulation of CaSR activity might serve as a novel pharmacological target to prevent and treat liver disease.
authors.affiliation: Department of Pathophysiology, Harbin Medical University, Harbin, China.
authors.forename: Wen-Jing
authors.initials: WJ
authors.lastname: Xing
authors.forename: Fan-Juan
authors.initials: FJ
authors.lastname: Kong
authors.forename: Guang-Wei
authors.initials: GW
authors.lastname: Li
authors.forename: Kun
authors.initials: K
authors.lastname: Qiao
authors.forename: Wei-Hua
authors.initials: WH
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Shu-Zhi
authors.initials: SZ
authors.lastname: Bai
authors.forename: Yu-Hui
authors.initials: YH
authors.lastname: Xi
authors.forename: Hong-Xia
authors.initials: HX
authors.lastname: Li
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
authors.forename: Huan
authors.initials: H
authors.lastname: Ren
authors.forename: Ling-Yun
authors.initials: LY
authors.lastname: Wu
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Chang-Qing
authors.initials: CQ
authors.lastname: Xu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D045304:Cytochromes c / Q000235:genetics / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000378:metabolism; D022781:Hepatocytes / Q000166:cytology* / Q000378:metabolism*; D000072181:Inositol Polyphosphate 5-Phosphatases; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D051381:Rats; D011915:Rats, Inbred BUF; D044169:Receptors, Calcium-Sensing / Q000235:genetics / Q000378:metabolism*; D015427:Reperfusion Injury / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D015398:Signal Transduction / Q000502:physiology; D010738:Type C Phospholipases / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D044169:Receptors, Calcium-Sensing; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D048049:Extracellular Signal-Regulated MAP Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D010744:Phosphoric Monoester Hydrolases; D000072181:Inositol Polyphosphate 5-Phosphatases; D010738:Type C Phospholipases; D053148:Caspase 3; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; D002118:Calcium