In the transgenic A53T mice,early low-dose ghrelin at the physiological level showed its neuroprotectionvia enhanced dopaminergic neuron performance and inhibited microglialproliferation and proinflammatory cytokine expression. This can be supported by data which reportedthat both total ghrelin and AG were decreased in PD patients afterassessing them in 291 patients with stages one to three of PD against301 healthy controls, with an interesting finding which stated thatthe decrement was nearly the same regardless of the disease stage. The gene discussed is GHRL; the disease is Parkinson disease.