BACKGROUND:Many factors can cause disc degeneration,including aging,nutritional deficiency,and mechanical factors.The mechanical load is considered to be a very important factor,but its mechanism is still unclear. OBJECTIVE:To investigate the role of sclerostin(SOST)and Wnt/β-catenin signaling pathways in inducing degeneration of endplate cartilage. METHODS:Cartilage endplate cells were extracted from 4-week-old male Sprague-Dawley rats.Compressive stress was applied to endplate chondrocytes in vitro using a mechanical loading apparatus,and the cell viability was determined by the cell counting kit-8 assay at 1,3,5,and 7 days after compression.Western blot,reverse transcription quantitative PCR,and cellular immunofluorescence techniques were employed to examine intracellular cartilage markers(Aggrecan and type Ⅱ collagen)as well as calcification-related factors(Runx2 and osteocalcin).The expression of extracellular matrix degradation enzyme and genes related to the signaling pathway(SOST and β-catenin)was also analyzed. RESULTS AND CONCLUSION:Under compressive stress,the cell activity of endplate chondrocytes increased with both the duration and intensity of stress.Furthermore,the expression levels of Aggrecan and type Ⅱ collagen decreased in endplate cells under compressive stress,while those of calcification-related factors(Runx2 and osteocalcin)increased.Additionally,compressive stress promoted extracellular matrix degradation in endplate chondrocytes,leading to an increase in matrix metalloproteinase 3 and matrix metalloproteinase 13 expression.Abnormalities were observed in the Wnt/β-catenin signaling pathway within these cells under compressive stress,characterized by a decrease in specific inhibitory factor SOST expression accompanied by abnormal accumulation of β-catenin.To conclude,decreased SOST expression in endplate chondrocytes under compressive stress activates the Wnt/β-catenin signaling pathway,thereby promoting calcification,degeneration and extracellular matrix degradation in the cartilage endplate.

Objective To summarize and explore the individualized surgical treatment strategy and prognosis of anomalous aortic origin of coronary artery (AAOCA). Methods The clinical data of children with AAOCA admitted to Shanghai Children's Medical Center from March 2018 to August 2021 were retrospectively analyzed. Results A total of 17 children were enrolled, including 13 males and 4 females, with a median age of 88 (44, 138) months and a median weight of 25 (18, 29) kg. All patients received operations. The methods of coronary artery management included coronary artery decapitation in 9 patients, coronary artery transplantation in 5 patients and coronary artery perforation in 3 patients. One patient with severe cardiac insufficiency (left ventricular ejection fraction 15%) received mechanical circulatory assistance after the operation for 12 days. No death occurred in the early postoperative period, the average ICU stay time was 4.3±3.0 d, and the total hospital stay was 14.4±6.1 d. All the children received regular anticoagulation therapy for 3 months after discharge. The median follow-up time was 15 (13, 24) months. All patients received regular anticoagulation therapy for 3 months after discharge. No clinical symptoms such as chest pain and syncope occurred again. The cardiac function grade was significantly improved compared with that before operation. Imaging examination showed that the coronary artery blood flow on the operation side was unobstructed, and no restenosis occurred. Conclusion AAOCA is easy to induce myocardial ischemia and even sudden cardiac death. Once diagnosed, operation should be carried out as soon as possible. According to the anatomic characteristics of coronary artery, the early effect of individualized surgery is satisfactory, and the symptoms of the children are significantly improved and the cardiac function recovers well in the mid-term follow-up.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.