Acupuncture upregulates G protein coupled activity in SAMP8 mice

Transmembrane and intracellular signal transduction of G protein is closely related to the pathophysiology of Alzheimer's disease (AD).

To explore the effects of Sanjiao acupuncture on G protein signal transduction pathways in the pathogenesis of AD.

36 senescence-accelerated (SAM) prone 8 mice were divided into three groups that remained untreated (SAMP8, n=12) or received Sanjiao acupuncture (SAMP8+SA, n=12) or control acupuncture (SAMP8+CA, n=12). An additional control group of SAM resistant 1 mice was included (SAMR1 group, n=12). Morris water maze tests were used to investigate learning and memory abilities. Immunoprecipitation and Western blotting were used to study expression of G protein subunits and their activities in the cortex/hippocampus.

Behavioural analysis showed that acupuncture attenuated the severe cognitive deficits observed in untreated/CA-treated SAMP8 mice. The findings of the G protein activation assays via immunoprecipitation and Western blots were that the physiologically coupled activation rate (PCAR) and maximal coupled activation rate (MCAR) of Gα_s and Gα_i were decreased in the cortex of SAMP8 vs SAMR1 mice. Sanjiao acupuncture induced an upregulation in the PCAR of Gα_s and Gα_i. In the hippocampus of untreated SAMP8 mice, the PCAR of Gα_s and MCAR of both Gα_s and Gα_i declined, and Sanjiao acupuncture was associated with an upregulation in the MCAR of Gα_s and Gα_i. There were no significant differences in Gα_s and Gα_i expression between the groups.

Sanjiao acupuncture attenuates cognitive deficits in a mouse model of AD via upregulation of G protein activity and stabilisation of the cellular signal.