Neurotransmitters in rats fed fumonisin B1

Area of Science:

• Toxicology
• Neuroscience
• Mycology

Background:

• Fusarium moniliforme produces fumonisin B1, linked to equine leukoencephlomalacia.
• Previous studies indicated F. moniliforme toxins alter rat brain 5-hydroxyindoleacetic acid (5HIAA) and serotonin (5HT) levels.
• The neurochemical impact of isolated fumonisin B1 requires further investigation.

Purpose of the Study:

• To investigate the neurochemical effects of fumonisin B1 on rat brain and pineal gland.
• To determine if fumonisin B1 alone replicates the 5HIAA and 5HT imbalances observed with F. moniliforme exposure.
• To assess potential sex-based differences in neurochemical responses to fumonisin B1.

Main Methods:

• Male and female rats were administered fumonisin B1 at 15, 50, and 150 ppm for four weeks.
• Brain and pineal gland tissue concentrations of norepinephrine, dopamine, and serotonin metabolites (5HIAA, 5HT) were analyzed.
• Ratios including 5HIAA:5HT and norepinephrine:dopamine were calculated and compared.

Main Results:

• No significant changes were observed in brain 5HT, 5HIAA, or their ratios in rats treated with fumonisin B1.
• A decrease in the norepinephrine to dopamine ratio was noted in male rats receiving 150 ppm of fumonisin B1.
• No significant alterations in pineal gland neurochemical levels were detected.

Conclusions:

• Fumonisin B1 alone does not appear to cause the previously observed 5HT and 5HIAA imbalances in rat brains.
• A potential disruption of brain norepinephrine and dopamine systems may occur at high fumonisin B1 doses.
• Other mycotoxins produced by Fusarium moniliforme may be responsible for the neurotoxic effects associated with equine leukoencephlomalacia.