TGFB1 and Parkinson disease: The findings demonstrated a noteworthy decrease in total distance, average speed, central time, and latency within the PD + hOM-MSCs + shRNA TGF-β1 group compared to the PD + hOM-MSCs group, these aforementioned indices of neurologic function exhibited a significant increase in the PD + TGF-β1 group, whereas there was a marked decrease when comparing the PD + AAV ALK + TGF-β1 group with the PD + TGF-β1 group (Fig. 6a, b).