Nevertheless, limitations exist, including the use of only one PD mouse model, which cannot fully simulate the complex pathological mechanism of human PD; the use of only one probiotic strain, which cannot reflect the diversity and interaction of intestinal microbiota; observation of only some changes in genes and neurotransmitters, without exploring the specific molecular mechanism of the PGC-1α signaling pathway; and a 4-week experimental duration, without considering the long-term effects and safety. The gene discussed is PPARGC1A; the disease is Parkinson disease.