The current study's findings showed that administering synbiotics, particularly Lactobacillus acidophilus with inulin, as an adjuvant with l-dopa in PD patients appears to be safe and effective, and represent a promising neuro-protective and therapeutic agent in treatment of PD, since it increased the levels of the neuroprotective neurotrophin BDNF, and decreased the levels of the oxidative stress marker MDA, and the inflammatory marker TNF-α, which was linked to a clinical improvement in both motor and non-motor symptoms compared to control. The gene discussed is BDNF; the disease is Parkinson disease.