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Modulation of paracetamol-induced hepatotoxicity by phosphodiesterase isozyme inhibition in rats: a preliminary study

Martins Ekor1, Adesina O Odewabi, Oluwafemi E Kale

  • 1Department of Paharmacology, Olabisi Onabanjo University, Sagamu, Nigeria. m.ekor@uccsms.edu.gh

Journal of Basic and Clinical Physiology and Pharmacology
|February 22, 2013
PubMed
Abstract

Insights

Phosphodiesterase (PDE) inhibitors, including selective PDE-5 inhibitors like sildenafil, show promise in protecting the liver from paracetamol (PCM)-induced toxicity. These findings suggest PDE inhibition as a potential therapeutic strategy for managing drug-induced liver injury.

Area of Science:

  • Hepatology
  • Pharmacology
  • Biochemistry

Background:

  • Nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway dysregulation is implicated in liver cirrhosis.
  • Modulating NO metabolism in the liver can reduce intrahepatic resistance and portal pressure in cirrhosis.

Purpose of the Study:

  • To investigate the potential of phosphodiesterase-5 (PDE-5) inhibitors and non-selective PDE inhibitors in ameliorating paracetamol (PCM)-induced hepatic toxicity.
  • To assess the protective effects of sildenafil and aminophylline against PCM-induced liver damage in a rat model.

Main Methods:

  • Hepatotoxicity was induced in rats using paracetamol (PCM) at 250 mg/kg.
  • PCM-treated rats received either sildenafil (selective PDE-5 inhibitor) or aminophylline (non-selective PDE inhibitor) at 10 mg/kg.
  • Control rats received physiological saline.

Main Results:

  • Both sildenafil and aminophylline significantly attenuated PCM-induced hepatotoxicity, reducing elevated liver enzymes (AST, ALT) and lipid peroxidation.
  • Sildenafil and aminophylline partially prevented PCM-induced decreases in total protein and albumin.
  • The inhibitors increased glutathione levels and did not significantly alter cholesterol or triglyceride levels.

Conclusions:

  • Pharmacological inhibition of PDE isozymes represents a potential protective strategy against paracetamol-induced liver toxicity.
  • These preliminary findings warrant further investigation into PDE inhibitors for managing drug-induced liver injury.

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