Comparative study on susceptibility to 1-bromopropane in three mice strains

Area of Science:

• Toxicology
• Comparative toxicology
• Biochemistry

Background:

• 1-bromopropane (1BP) is known for neurotoxicity and reproductive toxicity in humans and animals.
• Strain-specific differences in susceptibility to chemical toxicants are not fully understood.
• Investigating these differences can elucidate biological mechanisms of toxicity.

Purpose of the Study:

• To investigate strain differences in susceptibility to 1-bromopropane (1BP) in mice.
• To identify biological factors contributing to strain-dependent toxicity.
• To compare the susceptibility of mice and rats to 1BP toxicity.

Main Methods:

• Three mouse strains (C57BL/6J, DBA/2J, BALB/cA) were exposed to 1BP (0-250 ppm) via inhalation for 28 days.
• Hepatotoxicity and male reproductive toxicity were evaluated.
• Hepatic CYP2E1 levels, glutathione-S-transferase (GST) activity, glutathione (GSH) status, and related mRNA levels were assessed.

Main Results:

• BALB/cA mice exhibited the highest susceptibility to 1BP-induced hepatotoxicity, showing increased liver necrosis.
• BALB/cA mice had higher hepatic CYP2E1 protein levels and lower GSH content and GST activity compared to DBA/2J mice.
• 1BP exposure decreased sperm count and motility and increased abnormal sperm in all strains in a dose-dependent manner.

Conclusions:

• BALB/cA mice are the most susceptible to 1BP hepatotoxicity among the tested strains.
• CYP2E1, GSH levels, and GST activity likely contribute to strain-dependent susceptibility to 1BP hepatotoxicity.
• Mice are significantly more susceptible to 1BP hepatotoxicity and reproductive toxicity than rats.