electroacupuncture in a chronic hypoxia-induced cognitive dysfunction mouse model

Cognitive Improvement in Chronic Hypoxia Mice with Acupuncture

The global population is currently facing a critical aging problem, resulting in a rapid increase in the prevalence of cognitive disorders. The worldwide incidence of cognitive impairment is approximately 53.97 per 1000 person-years1. Chronic cerebral hypoxia caused by vascular dysfunction or circulatory/respiratory disorders remains one of the major risk factors for age-related dementia2. Previous studies have demonstrated that cerebral hypoxia can increase amyloid-&#946; deposition by modifying BACE1 expression3. Additionally, hypoxia has been associated with glial-cell dysregulation and neuroinflammation4,5. Despite the growing magnitude of this issue, effective Western medicines for preventing chronic hypoxia-induced cognitive decline are currently lacking. Non-pharmacological traditional Chinese medicine, particularly acupuncture, has been used for thousands of years to treat cognitive disorders and has shown promising results in alleviating neurodegenerative diseases6,7. The Baihui, Shenting, and Zusanli acupoints are effective points for treating cognitive dysfunction8,9. Clinical studies have demonstrated that electro-acupuncture therapy significantly improves the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) scores in patients with vascular cognitive impairment and effectively ameliorates cognitive dysfunction8. Although studies have suggested that acupuncture can significantly enhance the memory ability of rats with arterial ligation-an acute cerebral hypoxia models10, an acute cerebral hypoxia model, there is no report on the effects of acupuncture in any rodent model with chronic hypoxia-induced cognitive disorders. The lack of research into the mechanism has considerably impeded its clinical application. 
Previous research has demonstrated that subjecting rats to a hypoxic environment for a period of 8 weeks can significantly elevate levels of oxidative stress and inflammation in the brain, resulting in a decline in memory function11. The present study aims to investigate the impact of acupuncture on rodent models in order to further our understanding. It is worth noting, however, that anesthesia is typically required during acupuncture treatment in rodents due to the potential for agitation during repeated stimulation. Prolonged anesthesia can significantly impact cognitive function in mice, as most anesthetic drugs can suppress neural activity and impede information processing, leading to behavioral deficits12. Several studies have shown that administering 2.5% sevoflurane for a duration of 6 h can notably impair spatial memory, learning ability, and attention in mice13. Furthermore, evidence suggests that high doses of anesthesia may result in neuronal death or nerve damage in mice14. Therefore, it is imperative to identify a suitable approach to minimize the overall amount of anesthesia used. In this study, we introduce an effective acupuncture method for treating mice with cognitive impairment, along with behavioral tests to assess their memory abilities. Importantly, we present a modified pre-treatment anesthesia technique that can effectively reduce the total dosage of anesthesia administered during the experiment.

Author Spotlight: Improving Anesthesia Protocols for Enhanced Mouse Acupuncture Research

Acupuncture Treatment in a Mouse Model of Chronic Hypoxia-Induced Cognitive Dysfunction

Selecting the right anesthesia protocol is crucial for conducting mouse acupuncture. Due to potential cognitive impairment associated with prolonged anesthesia, it represents an essential initial challenge, demanding careful consideration to minimize cognitive function risks in mice during the procedure. In this study, we propose an improved protocol that helps to minimize functional and behavioral abnormalities caused by excessive anesthesia dosing, and enhances the accuracy of the experiments.In the future, our laboratory aims to study the underlying mechanisms of acupuncture despite its observable therapeutic effects on behavior and pathology. Our research will focus on unraveling acupuncture to gain a deeper understanding of its mechanisms.

Electroacupuncture in a Chronic Hypoxia-Induced Cognitive Dysfunction Mouse Model

To begin, place an anesthetized mouse with chronic hypoxia-induced cognitive dysfunction on a heating pad set at 37 degrees Celsius. Then, connect the anesthesia machine to the mouth and nose of the mouse. For electroacupuncture, locate the GV20 acupoint on the midline of the forehead between the line connecting the ear tips.Next, locate the GV24 acupoint 1.3 millimeters directly above the midpoint of the eyes. Then find the ST36 acupoint on the outside of the knee joint about two millimeters below the fibula head. Prepare disposable acupuncture needles and an electroacupuncture device for the procedure.Now place the mouse in the prone position. With the right thumb, index finger and middle finger, hold a stainless steel needle. Puncture the points GV20 and GV24 transversely at a depth of two millimeters.Then, puncture the ST36 acupoint vertically to a depth of three to four millimeters. Connect the proximal end of the needles at GV20 and the left ST36 to one electrode set. Connect the proximal end of the needles at GV24 and the right ST36 to another electrode set.Select the Continuous Wave mode on the electroacupuncture device and set the electric current intensity to two milliamperes and the frequency to two hertz. Confirm the ideal treatment by observing local mild tremors at the acupoints. Use adhesive tape to secure the horizontally inserted needle and the connection line.Administer the treatment for 30 minutes each day for six consecutive days. Electroacupuncture appear to improve the exploratory activity of hypoxia-induced mice. The treated mice also displayed a more organized behavior.

Research

JoVE Journal

Behavior

The treatment of central nervous disorders has consistently posed significant challenges to the medical field. Acupuncture, a non-pharmacological practice ...