Background: This study investigated the impact of repetitive
transcranial magnetic stimulation (rTMS) on serum levels of Amyloid-
(A) as well as the ectodomain of p75 neurotrophin receptor (p75ECD) in
patients with Alzheimer’s disease (AD). Methods: A total of 46 patients
diagnosed with AD between June 1, 2020 and December 31, 2021 were randomized to
undergo either 20 Hz rTMS treatment of the left dorsolateral prefrontal cortex
(DLPFC) or sham procedure. Cognitive function and activity of daily living were
evaluated. Neuropsychological tests and blood samples were gathered at baseline
and at 2, 3, 4, and 6 weeks after rTMS therapy. Results: There were no
evident differences between rTMS group and sham group in serum A40,
A42, total A, ApoE, and p75ECD standards at baseline
(p 0.05). Serum levels of A40, A42, as well as
total A, were significantly lower in the rTMS group at 3, 4 and 6 weeks
relative to the sham group (p 0.05). Serum p75ECD levels in the rTMS
group were significantly higher than those of the sham group at 3, 4 and 6 weeks
(p 0.05). Levels of serum A40 (r: –0.78, –0.83, –0.68,
respectively), A42 (r: –0.76, –0.76, –0.61, respectively) and total
A (r: –0.74, –0.81, –0.66, respectively) were negatively correlated
with MoCA, MMSE and MBI scores, while serum p75ECD levels (r: 0.84, 0.90, 0.72,
respectively) were positively correlated (p 0.01). The level of
serum A40 (r = 0.77), A42 (r = 0.69) as well as total
A (r = 0.73) were positively correlated with ADAS-cog score, while
p75ECD levels (r = –0.86) were negatively correlated (p 0.01).
Conclusions: The results of this study suggest that rTMS may decrease
serum A levels and increase serum p75ECD levels in patients with AD,
offering insight into a potential underpinning mechanism of rTMS.