Preclinical Evaluation of Synthetic Biology-Driven Engineered <i>Escherichia coli</i> Nissle 1917 as a Living Therapeutic for Sustained L-DOPA Delivery

High Resolution Image Download MS PowerPoint Slide Dopamine deficiency resulting from nigrostriatal dopaminergic neuronal damage manifests as extrapyramidal motor symptoms of Parkinson’s disease (PD). Oral tablet dosing of levodopa, administered 3–4 times a day, remains the standard of care due to its tolerability and effectiveness; however, it is prone to deleterious side effects, including off-periods and levodopa-induced dyskinesia after long-term use. Herein, using synthetic biology approaches, we developed and systematically evaluated the feasibility of a probiotic-based live-biotherapeutic system to continuously deliver L-DOPA stably, thereby relieving motor symptoms. Our data demonstrate that our engineered plasmid-based L-DOPA-expressing Escherichia coli Nissle 1917 probiotic strain (EcN 2 LDOPA-P3 ) efficiently produced up to 12,000 ng/mL L-DOPA in vitro. In mouse model systems, EcN 2 LDOPA-P3 readily colonized for up to 48 h, achieved steady-state plasma L-DOPA concentrations, and increased brain L-DOPA and dopamine levels by 1- to 2-fold. Lastly, EcN 2 LDOPA-P3 significantly diminished motor and nonmotor behavioral deficits in a mouse model of PD compared to traditional chemical L-DOPA therapy. These findings support the therapeutic feasibility of a noninvasive, orally administered bioengineered bacterial therapy for the chronic delivery of L-DOPA, which may address limitations associated with current treatment alternatives.