BDNF and major depressive disorder: Numerous previous studies have shown that acupuncture including manual acupuncture (MA) and electroacupuncture (EA) alleviate symptoms of stroke, AD, PD and depression by increasing the levels of BDNF[6] and promoting neurotrophic effects.[7,8] Micro-RNAs (miRNAs) function as posttranscriptional regulators by binding to the 3’-UTR of target mRNAs, leading to their degradation or translational repression.[9] Acupuncture can regulate some miRNAs which directly bind with the 3′-UTR of BDNF to regulate BDNF.