ADRB2 and Parkinson disease: Considering that β1-AR signaling increased neuroinflammation and dopaminergic neuron degeneration in the hα-SYN mouse model of PD (Figs. 4, 5, 6), it is possible that 6OHDA injection in the striatum could change β-AR expression patterns in the brain favoring β1-AR signaling leading to dopaminergic neuron degeneration after DSP-4 pretreatment.