Oat1, Oat3and Mrp2Mediated Protective Effect of JBP485on Acute Liver/renal Injury and Its Molecular Pharmacokinetic Mechanism
|School||Dalian Medical University|
|Keywords||JBP485 obstructive jaundice acute renal failure Oat1 Oat3 Mrp2|
Objective: Acute liver and renal injury are common diseases in clinic. Previousstudies showed the expressions of organic anion transporter1and3(Oat1, Oat3) andmultidrug resistance-associated protein2(Mrp2) were regulated during acute liver andrenal injury. Oat1and Oat3are located on the proximal tubule cells of kidney. Mrp2islocated in apical membranes of proximal tubule cells. ANIT (alpha-naphthylisothiocyanate) could induce obstructive jaundice by inducing biliary cellsapoptosis. The strong side effect of cisplatin is to induce acute renal failure.Cyclo-trans-4-L-hydroxyprolyl-L-serine (JBP485) is a dipeptide purified from Laennec(human placenta hydrolysate), which exhibit anti-hepatitis activity. The aim of thisstudy is to examine whether JBP485has the protective effect on the acute liver andrenal injury, and whether the mechanism is related to the regulation of expression ofOat1, Oat3and Mrp2.Methods:1Obstructive Jaundice: Male Wistar rats were divided into fourgroups, control, model, positive control treatment (silymarin) and JBP485treatment (50mg/kg and100mg/kg). Bilirubin (BIL), alanine amiotransferase (ALT) and aspartatetransaminase (AST) were determined48h after ANIT treatment. Meanwhile, thechanges in live histology were observed between the different groups. Plasmaconcentration and cumulative urinary excretion of JBP485by intravenousadministration in vivo, the uptake of JBP485in kidney slices in vitro were examined.RT-PCR and western-blotting were applied to analyze mRNA and protein of Oat1, Oat3and Mrp2in the kidney. The concentration of BIL in urine was determined for24h and48h after ANIT treatment.2Acute renal injury: Male Wistar rats were divided intothree groups, control, model, and JBP485treatment (25mg/kg,50mg/kg and100 mg/kg). Creatinine, Blood Urea Nitrogen (BUN) and Indoxyl Sulphate (IS) in plasmawere determined72h after cisplatin treatment. Meanwhile, the changes in GlomerularFiltration Rate (GFR) were observed between the different groups. Malondialdehyde(MDA) and Superoxide Dismutase (SOD) in kidney were determined. Plasmaconcentration and cumulative urinary excretion of PAH by intravenous administrationin vivo, the uptake of PAH in kidney slices in vitro were examined. qRT-PCR,western-blotting, immunochemistry and immunofluorescence were applied to analyzethe changes in mRNA and protein of Oat1, Oat3and Mrp2in the kidney. Theconcentration of IS in urine was determined48h after cisplatin treatment.Results:1Obstructive Jaundice:(1) Compared to control group, the modelgroup:(a) BIL, ALT and AST were markedly increased in rat serum;(b)The infiltrationand hepatocyte necrosis were observed in hepatic portal area;(c) The plasmaconcentration of JBP485was increased markedly, whereas cumulative urinary excretionof JBP485and the uptake of JBP485in kidney slices were decreased remarkably;(d)The mRNA and protein of Oat1and Oat3were decreased, the mRNA and protein ofMrp2was increased;(e) The24h and48h cumulative urinary excretion of BIL wasincreased.(2) Compared to model group, the JBP485treatment group:(a) BIL,ALT and AST were reduced in rat serum;(b) The infiltration and Hepatocyte necrosiswere improved;(c) The mRNA and protein of Mrp2was further increased;(d) The24hand48h cumulative urinary excretion of JBP485were further increased.2Acute renalinjury:(1) Compared to control group, the model group:(a) Creatinine, BUN andIS were markedly increased in rat serum;(b) The concentration of MDA increased, SODvalues decreased in kidney tissue;(c) GFR was decreased;(d) The plasma concentrationof PAH was increased markedly, whereas cumulative urinary excretion of PAH and theuptake of PAH in kidney slices were decreased remarkably;(d)The mRNA and proteinof Oat1and Oat3were decreased, the mRNA and protein of Mrp2was increased;(e)Oat1and Oat3are downregulated in immunochemistry and immunofluorescenceexperiments;(f) The cumulative urinary excretion of IS was increased.(2) Comparedto model group, the JBP485treatment group:(a) Creatinine, BUN and IS werereduced in rat serum;(b) The concentration of MDA decreased, SOD values increasedin kidney tissue;(c) GFR was improved;(d) The mRNA and protein of Mrp2wasfurther increased;(e) Immunochemistry and immunofluorescence results showed Oat1and Oat3are improved;(f) The cumulative urinary excretion of IS was furtherincreased. Conclusions:(1)The expression of Oat1and Oat3were downregulated, and theexpression of Mrp2was upregulated during acute renal and live injury;(2) The increasedexpression of Mrp2could further eliminate the accumulated toxins in body, it is anadapt protective response against the injury;(3) JBP485promotes the urinary excretionof toxins by further activating renal Mrp2. That therefore gives in part the explanationabout its protective effect on acute liver and renal injury.