Rubratoxin B mycotoxicosis in the Mongolian gerbil

Area of Science:

• Toxicology
• Mycotoxicology
• Pathology

Background:

• Rubratoxin B is a mycotoxin produced by Penicillium species.
• Understanding its toxicity is crucial for risk assessment in agriculture and food safety.

Purpose of the Study:

• To determine the median lethal dose (LD50) of rubratoxin B in Mongolian gerbils.
• To characterize the acute and subchronic toxic effects of rubratoxin B on kidney and liver tissues.
• To evaluate the morphopathogenesis of rubratoxin B-induced lesions.

Main Methods:

• Median lethal dose (LD50) determination via intraperitoneal (ip) injection in Mongolian gerbils.
• Gross and histopathological examination of major organs (kidneys, liver, spleen) at various time points post-administration.
• Biochemical analysis of serum markers, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and potassium (K+).
• Urinalysis to assess renal function.

Main Results:

• The ip LD50 of rubratoxin B was determined to be 2.0 mg/kg body weight.
• Acute exposure caused kidney pallor, liver mottling, and splenic congestion, with histopathology revealing renal tubular necrosis and hepatocyte degeneration.
• Repeated exposure demonstrated dose-dependent and cumulative toxicity, leading to renal tubular degeneration/necrosis and focal hepatocyte necrosis.
• Elevated serum AST and ALT levels indicated hepatic damage, while increased serum K+ and urinalysis findings confirmed renal tubular injury.

Conclusions:

• Rubratoxin B is acutely toxic to Mongolian gerbils, primarily targeting the kidneys and liver.
• The toxic effects are dose-dependent and cumulative, with repeated exposure exacerbating renal and hepatic damage.
• Rubratoxin B poses a significant toxicological risk, necessitating careful monitoring and control in relevant environments.