In addition, a recent study demonstrated that ethyl stearate, isolated from Plastrum testudinis and also present in MOE, increased the expression of tyrosine hydroxylase (an enzyme required for dopamine synthesis) and inhibited alpha-synuclein in rats, indicating a potential neuroprotective effect in Parkinson’s disease (Ye et al., 2021). The gene discussed is TH; the disease is Parkinson disease.