Generation of a Rat Model of Acute Liver Failure by Combining 70% Partial Hepatectomy and Acetaminophen

Summary

The acute liver failure animal model developed in the current study presents a feasible alternative for the study of potential therapies. The current model employs the combined effect of physical and drug-induced hepatic injury and provides a suitable time window to study the potential of novel therapies.

Abstract

Acute liver failure (ALF) is a clinical condition caused by various etiologies resulting in the loss of metabolic, biochemical, synthesizing, and detoxifying functions of the liver. In most irreversible liver damage cases, orthotropic liver transplant (OLT) remains the only available treatment. To study the therapeutic potential of a treatment for ALF, its prior testing in an animal model of ALF is essential. In the current study, an ALF model in rats was developed by combining 70% partial hepatectomy (PHx) and injections of acetaminophen (APAP) that provides a therapeutic window of 48 h. The median and left lateral lobes of the liver were removed to excise 70% of the liver mass and APAP was given 24 h postsurgically for 2 days. Survival in ALF-induced animals was found to be severely decreased. The development of ALF was confirmed by altered serum levels of the enzymes alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP); changes in prothrombin time (PT); and assessment of the international normalized ratio (INR). Study of the gene expression profile by qPCR revealed an increase in expression levels of genes involved in apoptosis, inflammation, and in the progression of liver injury. Diffused degeneration of hepatocytes and infiltration of immune cells was observed by histological evaluation. The reversibility of ALF was confirmed by the restoration of survival and serum levels of ALT, AST, and ALP after intrasplenic transplantation of syngeneic healthy rat hepatocytes. This model presents a reliable alternative to the available ALF animal models to study the pathophysiology of ALF as well as to evaluate the potential of a novel therapy for ALF. The use of two different approaches also makes it possible to study the combined effect of physical and drug-induced liver injury. The reproducibility and feasibility of current procedure is an added benefit of the model.

Introduction

Acute liver failure (ALF) is defined by the American Association for the Study of Liver Diseases as rapid development of acute liver injury without any prior signs of damage and is characterized by severe impairment of the synthetic, metabolic, and detoxifying functions of the liver¹. ALF differs from chronic liver failure where the failure occurs as a result of liver injury caused over a long period of time and from acute chronic liver failure (ACLF), where abrupt liver damage takes place as a result of chronic liver diseases^2,3,4. The only available ....

Protocol

The procedure described below has been approved by the Institutional Animal Ethics Committee of National Institute of Immunology, New Delhi. The serial reference number of the approval is IAEC#355/14.

1. Preparation

1. Prepare for the surgical procedure as described earlier by Das B et al.²⁶.
2. Use 6–8-week-old inbred Wistar rats with a body weight of 200–250 g.
3. House the animals under standard animal care conditions and feed them .......

Discussion

The development of an appropriate animal model for ALF is paramount for the better understanding of pathogenesis and progression of ALF. A well characterized ALF animal model also provides the opportunity for the development and trial of new therapeutic approaches against ALF. Many attempts have been made to develop a clinically relevant model of ALF^{6,12,21,23,46}

Materials

Name	Company	Catalog Number	Comments
Acetaminophen (Biocetamol)	EG Pharmaceuticals		No specific Catalog Number (Local Procurement)
Alkaline Phosphatase Kit (DEA)	Coral Clinical System, India		No specific Catalog Number (Local Procurement)
Automated analyser	Tulip, Alto Santracruz, India	Screen Maaster 3000	Biochemical analyser for liver functional test
Betadine (Povidon-Iodine Solution)	Win-Medicare; India		No specific Catalog Number (Local Procurement)
Biological safety cabinet (Class I)	Kartos international; India		No specific Catalog Number (Local Procurement)
Bright Field Microscope	Olympus, Japan	LX51
Cefotaxime (Taxim®)	AlKem; India		cefotaxime sodium injection, No specific Catalog Number (Local Procurement)
Cell Strainer	Sigma; US	CLS431752
Collagenase Type I	Gibco by Life Technologies	17100-017
Cotton Buds	Pure Swabs Pvt Ltd; India		No specific Catalog Number (Local Procurement)
Drape Sheet	JSD Surgicals, Delhi, India		No specific Catalog Number (Local Procurement)
DPX Mountant	Sigma; US	6522
Eosin Y solution, alcoholic	Sigma; US	HT110132
Forceps	Major Surgicals; India		No specific Catalog Number (Local Procurement)
Gas Anesthesia System	Ugo Basile; Italy	211000
Glucose	Himedia, India	GRM077
Hair removing cream (Veet®)	Reckitt Benckiser, India		No specific Catalog Number (Local Procurement)
Hematoxylin Solution, Mayer's	Sigma; US	MHS16
Heparin sodium salt	Himedia; India	RM554
Hyaluronidase From Sheep Testes	Sigma; US	H6254
I.V. Cannula (Plusflon)	Mediplus, India	Ref 1732411420
Insulin Syringes	BD; US	REF 303060
Isoflurane (Forane®)	Asecia Queenborough	No B506	Inhalation Anaesthetic
Ketamine (Ketamax®)	Troikaa Pharmaceuticals Ltd.		Ketamine hydrochloride IP, No specific Catalog Number (Local Procurement)
Meloxicam (Melonex®)	Intas Pharmaceuticals Ltd; India		No specific Catalog Number (Local Procurement)
Micro needle holders straight & curved	Mercian; England	BS-13-8
Micro needle holders straight & curved	Mercian; England	BS-13-8
Microtome	Histo-Line Laboratories, Italy	MRS3500
Nylon Thread	Mighty; India		No specific Catalog Number (Local Procurement)
Paraformaldehyde	Himedia; India	GRM 3660
Percoll®	GE Healthcare	17-0891-01
Refresh Tears/Eyemist Gel	Allergan India Private Limited/Sun Pharma, India	P3060	No specific Catalog Number
RPMI	Himedia; India		No specific Catalog Number (Local Procurement)
Scalpel	Major Surgicals; India		No specific Catalog Number (Local Procurement)
Scissors	Major Surgicals; India		No specific Catalog Number (Local Procurement)
SGOT (ASAT) KIT	Coral Clinical System, India		No specific Catalog Number (Local Procurement)
SGPT (ALAT) KIT	Coral Clinical System, India		No specific Catalog Number (Local Procurement)
Shandon Cryotome E Cryostat	Thermo Electron Corporation; US		No specific Catalog Number
Sucrose	Sigma; US	S0389
Surgical Blade No. 22	La Medcare, India		No specific Catalog Number (Local Procurement)
Surgical Board	Locally made		No specific Catalog Number (Local Procurement)
Surgical White Tape	3M India; India	1530-1	Micropore Surgical Tape
Sutures	Ethicon, Johnson & Johnson, India	NW 5047
Syringes (1ml, 26 G)	Dispo Van; India		No specific Catalog Number (Local Procurement)
Trimmer (Clipper)	Philips	NL9206AD-4 DRACHTEN QT9005
Weighing Machine	Braun		No specific Catalog Number (Local Procurement)
William's E Media	Himedia; India	AT125
Xylazine (Xylaxin®)	Indian Immunologicals Limited		Sedative, Pre-Anaesthetic, Analgesic and muscle relaxant