title: Mechanisms underlying the effect of acupuncture on cognitive improvement: a systematic review of animal studies.
abstract: Acupuncture has been reported to be beneficial in treating cognitive impairment in various pathological conditions. This review describes the effort to understand the signaling pathways that underlie the acupunctural therapeutic effect on cognitive function. We searched the literature in 12 electronic databases from their inception to November 2013, with full text available and language limited to English. Twenty-three studies were identified under the selection criteria. All recruited animal studies demonstrate a significant positive effect of acupuncture on cognitive impairment. Findings suggest acupuncture may improve cognitive function through modulation of signaling pathways involved in neuronal survival and function, specifically, through promoting cholinergic neural transmission, facilitating dopaminergic synaptic transmission, enhancing neurotrophin signaling, suppressing oxidative stress, attenuating apoptosis, regulating glycometabolic enzymes and reducing microglial activation. However, the quality of reviewed studies has room for improvement. Further high-quality animal studies with randomization, blinding and estimation of sample size are needed to strengthen the recognition of group differences.
authors.affiliation: Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, Special Administrative Region, China, mason.leung@polyu.edu.hk.
authors.forename: Mason Chin Pang
authors.initials: MC
authors.lastname: Leung
authors.forename: Ka Keung
authors.initials: KK
authors.lastname: Yip
authors.forename: Yuen Shan
authors.initials: YS
authors.lastname: Ho
authors.forename: Flora Ka Wai
authors.initials: FK
authors.lastname: Siu
authors.forename: Wai Chin
authors.initials: WC
authors.lastname: Li
authors.forename: Belinda
authors.initials: B
authors.lastname: Garner
mesh_terms: D015670:Acupuncture Therapy; D000818:Animals; D001921:Brain / Q000502:physiology; D003072:Cognition Disorders / Q000503:physiopathology* / Q000628:therapy*; D004195:Disease Models, Animal; D008959:Models, Neurological; D015398:Signal Transduction / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology