A mistake in mice chow has led to a potential breakthrough in treating Parkinson’s Disease. Marcio Lazzarini was conducting experiments in mice in search of alternative treatments for Parkinson’s by administering 6-hydroxydopamine (6-OHDA)—a neurotoxin that causes dopaminergic neurons to die—when “only two of the 40 mice given 6-OHDA developed symptoms of Parkinsonism, while the rest remained healthy,” said Elaine Del-Bel, one of the study’s authors. Lazzarini realized the mice had been eating food containing doxycycline, a commonly prescribed antibiotic. The group repeated the experiment in a second group of mice delivering doxycycline via peritoneal injection with successful results. It turns out, the antibiotic reduces the toxicity of α-synuclein, a protein that can damage central nervous system cells and cause tremor, stiffness and slow involuntary movements.