Rotenone

Produces symptoms similar to Parkinson’s disease in rats [120] .

MPTP (1-methyl-4 phenyl-1,2,3,6-tetrahydropyridine)

Produces symptoms similar to Parkinson’s disease [121] . In mice, an injection of melatonin prevents much of the damage to fats and DNA in several parts of the brain after MPTP poisoning [122] . This may be the result of reconfiguring proteins to their normal state after MPTP exposure

3-NPA (3-nitropropionic acid)

Derived from a fungus that infects sugarcane, there have been recorded incidents of children eating the fungal-contaminated sugarcane and afterward developing a condition similar to Huntington’s disease [123] . In rats dosed with 3-NPA, melatonin was observed to prevent nerve cell loss, correct damaging behavior, prevent protein damage, and restore dopamine levels to their normal range [123] .

Cyanide

Cyanide is a very lethal poison that causes mass-death of nerve cells and seizures, which can easily lead to death [124] [125] . It also damages mitochondria inside of nerve cells. In mice, a prior dose of melatonin reduced the severity of seizures caused by a cyanide injection [125] . As well, in-vivo and in-vitro tests showed that mitochondrial DNA damage from potassium cyanide was lessened by melatonin [124] .