Efficacy and underlying mechanisms of acupuncture therapy for PTSD: evidence from animal and clinical studies

Effectiveness of electro-acupuncture for cognitive improvement on Alzheimer's disease quantified via PET imaging of sphingosine-1-phosphate receptor 1

INTRODUCTION

Electro-acupuncture (EA) has demonstrated potential in improving mild-to-moderate dementia in clinics, but the underlying scientific target remains unclear.

METHODS

EA was administered to APP/PS1 Alzheimer's disease (AD) mice, with untreated AD, and wild type (WT) mice serving as controls. The efficacy of EA was assessed by the Morris water maze cognitive functional tests. Brain magnetic resonance imaging-positron emission tomography (PET) scans using [18F]TZ4877 targeting sphingosine-1-phosphate receptor 1 (S1PR1) and [18F]AV45 targeting amyloid beta fibrils were conducted. The correlation between regional brain PET quantifications and cognitive functions was analyzed.

RESULTS

EA significantly improved cognitive and memory functions of AD (p  = 0.04) and reduced the uptake of [18F]TZ4877 in the cortex (p  = 0.02) and hippocampus (p  = 0.03). Immunofluorescence confirmed colocalizations of S1PR1 with glial fibrillary acidic protein and ionized calcium-binding adaptor molecule-1. Furthermore, immunohistochemistry showed a significant reduction of interleukin 1β and tumor necrosis factor α after EA treatment.

DISCUSSION

EA may reverse AD by suppressing neuroinflammation, and the PET imaging of S1PR1 seemed potent in evaluating the treatment for AD patients HIGHLIGHTS: Electro-acupuncture (EA) was administered to APP/PS1 Alzheimer's disease (AD) mice, with untreated AD, and wild type (WT) mice serving as controls. The efficacy of EA was assessed by the Morris water maze cognitive functional tests and positron emission tomography (PET) imaging quantifications. PET tracer [18F]AV45 was used to detect amyloid beta deposition. An increased uptake of [18F]AV45 was found in AD compared to WT mice, with significance observed only in the cortex and not in the hippocampus. EA treatment exhibited a trend toward reduced [18F]AV45 uptake in AD mouse brains post-treatment. However, statistical difference was not attained in most brain regions. EA "Baihui (DU20) and Sishencong (EX-HN1)" significantly improved cognitive and memory functions of AD (p = 0.04). Brain magnetic resonance imaging p(MRI)-positron emission tomography (PET) quantifications revealed that significantly reduced the uptake of [18F]TZ4877 in the cortex (p = 0.02) and hippocampus (p = 0.03) after EA treatment. The correlation between PET quantifications and cognitive functions was analyzed and the most notable correlations were found between escape latency (reaction cognitive and memory behavior) and volume distribution (VT) quantifications of [18F]TZ4877. VT quantifications of [18F]TZ4877 in key brain regions for cognitive and memory ability, such as the cortex and hippocampus, positively correlated with platform latency (cortex p < 0.01, r = 0.7102; hippocampus p < 0.01, r = 0.6891). Immunofluorescence confirmed colocalizations of S1PR1 with glial fibrillary acidic protein and ionized calcium-binding adaptor molecule-1 in the AD brain. And the EA treatment significantly reduced the signals in the cortex and hippocampus. Immunohistochemistry showed a significant reduction of interleukin 1β and tumor necrosis factor α after EA treatment. EA reversed AD by suppressing neuroinflammation in the cortex and hippocampus. The S1PR1 targeting PET tracer [18F]TZ4877 showed promise in evaluating the pathological progression of AD in clinical settings.

Acupuncture for Combat-Related Posttraumatic Stress Disorder: A Randomized Clinical Trial

Importance

Current interventions for posttraumatic stress disorder (PTSD) are efficacious, yet effectiveness may be limited by adverse effects and high withdrawal rates. Acupuncture is an emerging intervention with positive preliminary data for PTSD.

Objective

To compare verum acupuncture with sham acupuncture (minimal needling) on clinical and physiological outcomes.

Design, Setting, and Participants

This was a 2-arm, parallel-group, prospective blinded randomized clinical trial hypothesizing superiority of verum to sham acupuncture. The study was conducted at a single outpatient-based site, the Tibor Rubin VA Medical Center in Long Beach, California, with recruitment from April 2018 to May 2022, followed by a 15-week treatment period. Following exclusion for characteristics that are known PTSD treatment confounds, might affect biological assessment, indicate past nonadherence or treatment resistance, or indicate risk of harm, 93 treatment-seeking combat veterans with PTSD aged 18 to 55 years were allocated to group by adaptive randomization and 71 participants completed the intervention protocols.

Interventions

Verum and sham were provided as 1-hour sessions, twice weekly, and participants were given 15 weeks to complete up to 24 sessions.

Main Outcomes and Measures

The primary outcome was pretreatment to posttreatment change in PTSD symptom severity on the Clinician-Administered PTSD Scale-5 (CAPS-5). The secondary outcome was pretreatment to posttreatment change in fear-conditioned extinction, assessed by fear-potentiated startle response. Outcomes were assessed at pretreatment, midtreatment, and posttreatment. General linear models comparing within- and between-group were analyzed in both intention-to-treat (ITT) and treatment-completed models.

Results

A total of 85 male and 8 female veterans (mean [SD] age, 39.2 [8.5] years) were randomized. There was a large treatment effect of verum (Cohen d, 1.17), a moderate effect of sham (d, 0.67), and a moderate between-group effect favoring verum (mean [SD] Δ, 7.1 [11.8]; t90 = 2.87, d, 0.63; P = .005) in the intention-to-treat analysis. The effect pattern was similar in the treatment-completed analysis: verum d, 1.53; sham d, 0.86; between-group mean (SD) Δ, 7.4 (11.7); t69 = 2.64; d, 0.63; P = .01). There was a significant pretreatment to posttreatment reduction of fear-potentiated startle during extinction (ie, better fear extinction) in the verum but not the sham group and a significant correlation (r = 0.31) between symptom reduction and fear extinction. Withdrawal rates were low.

Conclusions and Relevance

The acupuncture intervention used in this study was clinically efficacious and favorably affected the psychobiology of PTSD in combat veterans. These data build on extant literature and suggest that clinical implementation of acupuncture for PTSD, along with further research about comparative efficacy, durability, and mechanisms of effects, is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT02869646.

Electroacupuncture modulates glutamate neurotransmission to alleviate PTSD-like behaviors in a PTSD animal model

Post-traumatic stress disorder (PTSD) is a mental disorder that develops after exposure to a traumatic event. Owing to the relatively low rates of response and remission with selective serotonin reuptake inhibitors as the primary treatment for PTSD, there is a recognized need for alternative strategies to effectively address the symptoms of PTSD. Dysregulation of glutamatergic neurotransmission plays a critical role in various disorders, including anxiety, depression, PTSD, and Alzheimer's disease. Therefore, the regulation of glutamate levels holds great promise as a therapeutic target for the treatment of mental disorders. Electroacupuncture (EA) has become increasingly popular as a complementary and alternative medicine approach. It maintains the homeostasis of central nervous system (CNS) function and alleviates symptoms associated with anxiety, depression, and insomnia. This study investigated the effects of EA at the GV29 (Yintang) acupoint three times per week for 2 weeks in an animal model of PTSD. PTSD was induced using single prolonged stress/shock (SPSS) in mice, that is, SPS with additional foot shock stimulation. EA treatment significantly reduced PTSD-like behavior and effectively regulated serum corticosterone and serotonin levels in the PTSD model. Additionally, EA treatment decreased glutamate levels and glutamate neurotransmission-related proteins (pNR1 and NR2B) in the hippocampus of a PTSD model. In addition, neuronal activity and the number of Golgi-impregnated dendritic spines were significantly lower in the EA treatment group than in the SPSS group. Notably, EA treatment effectively reduced glutamate-induced excitotoxicity (caspase-3, Bax, and pJNK). These findings suggest that EA treatment at the GV29 acupoint holds promise as a potential therapeutic approach for PTSD, possibly through the regulation of NR2B receptor-mediated glutamate neurotransmission to reduce PTSD-like behaviors.

P3a amplitude to trauma-related stimuli reduced after successful trauma-focused PTSD treatment

An elevated P3a amplitude to trauma-related stimuli is strongly associated with posttraumatic stress disorder (PTSD), yet little is known about whether this response to trauma-related stimuli is affected by treatment that decreases PTSD symptoms. As an analysis of secondary outcome measures from a randomized controlled trial, we investigated the latency and amplitude changes of the P3a in responses in a three-condition oddball visual task that included trauma-related (combat scenes) and trauma-unrelated (threatening animals) distractors. Fifty-five U.S. veterans diagnosed with combat-related PTSD were randomized to receive either active or sham repetitive transcranial magnetic stimulation (rTMS). All received cognitive processing therapy, CPT+A, which requires a written account of the index trauma. They were tested before and 6 months after protocol completion. P3a amplitude and response time decreases were driven largely by the changes in the responses to the trauma-related stimuli, and this decrease correlated to the decrease in PTSD symptoms. The amplitude changes were greater in those who received rTMS + CPT than in those who received sham rTMS + CPT, suggesting that rTMS plays beneficial role in reducing arousal and threat bias, which may allow for more effective engagement in trauma-focused PTSD treatment.