Transcutaneous Electrical Acupoint Stimulation Ameliorates Cognitive Function through PINK1/Parkin Mediated Mitophagy in VD Rats

Deciphering mitochondrial dysfunction: Pathophysiological mechanisms in vascular cognitive impairment

Vascular cognitive impairment (VCI) encompasses a range of cognitive deficits arising from vascular pathology. The pathophysiological mechanisms underlying VCI remain incompletely understood; however, chronic cerebral hypoperfusion (CCH) is widely acknowledged as a principal pathological contributor. Mitochondria, crucial for cellular energy production and intracellular signaling, can lead to numerous neurological impairments when dysfunctional. Recent evidence indicates that mitochondrial dysfunction-marked by oxidative stress, disturbed calcium homeostasis, compromised mitophagy, and anomalies in mitochondrial dynamics-plays a pivotal role in VCI pathogenesis. This review offers a detailed examination of the latest insights into mitochondrial dysfunction within the VCI context, focusing on both the origins and consequences of compromised mitochondrial health. It aims to lay a robust scientific groundwork for guiding the development and refinement of mitochondrial-targeted interventions for VCI.

The effect of acupuncture on oxidative stress in animal models of vascular dementia: a systematic review and meta-analysis

BACKGROUND

Growing evidence showed that acupuncture may improve cognitive function by reducing oxidative stress, key to the pathogenesis in vascular dementia (VaD), but this is yet to be systematically analysed. This study aimed to summarize and evaluate the effect of acupuncture on oxidative stress in animal models of VaD.

METHOD

Eight databases including PubMed, Embase, Web of Science, Cochrane library, CNKI, Wan Fang, CBM, and VIP were searched since their establishment until April 2023, for studies that reported the effect of acupuncture on oxidative stress in VaD animal models. Relevant literature was screened, and information was extracted by two reviewers. The primary outcomes were the levels of oxidative stress indicators. The methodological quality was assessed via the SYRCLE Risk of Bias Tool. Statistical analyses were performed using the RevMan and Stata software.

RESULTS

In total, 22 studies with 747 animals were included. The methodology of most studies had flaws or uncertainties. The meta-analysis indicated that, overall, acupuncture significantly reduced the expression of pro-oxidants including reactive oxygen species (standardized mean differences [SMDs] = -4.29, 95% confidence interval [CI]: -6.26, -2.31), malondialdehyde (SMD = -2.27, 95% CI: -3.07, -1.47), nitric oxide (SMD = -0.85, 95% CI: -1.50, -0.20), and nitric oxide synthase (SMD = -1.01, 95% CI: -1.69, -0.34) and enhanced the levels of anti-oxidants including super oxide dismutase (SMD = 2.80, 95% CI: 1.98, 3.61), glutathione peroxidase (SMD = 1.32, 95% CI: -0.11, 2.76), and catalase (SMD = 1.31, 95% CI: 0.05, 2.58) in VaD animal models. In subgroup analyses, acupuncture showed significant effects on most variables. Only partial modelling methods and treatment duration could interpret the heterogeneity of some outcomes.

CONCLUSION

Acupuncture may inhibit oxidative stress to improve cognitive deficits in animal models of VaD. Nevertheless, the methodological quality is unsatisfactory. More high-quality research with a rigorous design and further experimental researches and clinical trials are needed to confirm these findings.

SYSTEMATIC REVIEW REGISTRATION

This study was registered in PROSPERO (CRD42023411720).

Transcutaneous electrical acupoint stimulation for the prevention of postoperative delirium in elderly surgical patients: A systematic review and meta-analysis

Objective

This systematic review and meta-analysis aimed to evaluate the preventive effect of transcutaneous electrical acupoint stimulation on postoperative delirium in elderly surgical patients.

Methods

PubMed, CENTRAL, China National Knowledge Infrastructure, and WanFang databases were searched for randomized controlled trials regarding the effect of transcutaneous electrical acupoint stimulation on preventing postoperative delirium in elderly patients undergoing any type of surgery. The primary outcome was the incidence of postoperative delirium. The secondary outcome was the duration of postoperative delirium. All analyses were conducted using RevMan 5.3 and Stata 13.0 software.

Results

Twelve trials with 991 participants were included, and most of them were at high/unclear risk of bias. Meta-analysis showed transcutaneous electrical acupoint stimulation could reduce the incidence of postoperative delirium (RR = 0.40, 95%CI = 0.29 to 0.55, p < 0.00001) and shorten the duration of postoperative delirium (MD = -0.97 days, 95%CI = -1.72 to -0.22, p = 0.01). Subgroup analyses demonstrated that transcutaneous electrical acupoint stimulation reduced the incidence of postoperative delirium in elderly patients undergoing orthopedic surgery and thoracic surgery, but not digestive surgery; transcutaneous electrical acupoint stimulation with dilatational wave and with continuous wave were both beneficial; and transcutaneous electrical acupoint stimulation was favored when compared to blank and sham control.

Conclusion

Transcutaneous electrical acupoint stimulation could reduce the incidence of postoperative delirium and shorten the duration of postoperative delirium in elderly surgical patients. The findings should be interpreted with caution due to weak evidence. High-quality, large sample, and multi-center trials are needed to further confirm the preliminary findings.Systematic review registration: https://inplasy.com/inplasy-2022-7-0096/, identifier: INPLASY202270096.