Inhibition of a novel Dickkopf-1-LDL receptor-related proteins 5 and 6 axis prevents diabetic cardiomyopathy in mice.

BACKGROUND AND AIMS: Anti-hypertensive agents are one of the most frequently used drugs worldwide. However, no blood pressure-lowering strategy is superior to placebo with respect to survival in diabetic hypertensive patients. Previous findings show that Wnt co-receptors LDL receptor-related proteins 5 and 6 (LRP5/6) can directly bind to several G protein-coupled receptors (GPCRs). Because angiotensin II type 1 receptor (AT1R) is the most important GPCR in regulating hypertension, this study examines the possible mechanistic association between LRP5/6 and their binding protein Dickkopf-1 (DKK1) and activation of the AT1R and further hypothesizes that the LRP5/6-GPCR interaction may affect hypertension and potentiate cardiac impairment in the setting of diabetes. METHODS: The roles of serum DKK1 and DKK1-LRP5/6 signalling in diabetic injuries were investigated in human and diabetic mice. RESULTS: Blood pressure up-regulation positively correlated with serum DKK1 elevations in humans. Notably, LRP5/6 physically and functionally interacted with AT1R. The loss of membrane LRP5/6 caused by injection of a recombinant DKK1 protein or conditional LRP5/6 deletions resulted in AT1R activation and hypertension, as well as ß-arrestin1 activation and cardiac impairment, possibly because of multiple GPCR alterations. Importantly, unlike commonly used anti-hypertensive agents, administration of the anti-DKK1 neutralizing antibody effectively prevented diabetic cardiac impairment in mice. CONCLUSIONS: These findings establish a novel DKK1-LRP5/6-GPCR pathway in inducing diabetic injuries and may resolve the long-standing conundrum as to why elevated blood DKK1 has deleterious effects. Thus, monitoring and therapeutic elimination of blood DKK1 may be a promising strategy to attenuate diabetic injuries.

Tai Chi-Induced Exosomal LRP1 is Associated With Memory Function and Hippocampus Plasticity in aMCI Patients.

OBJECTIVES: The study was designed to identify the potential peripheral processes of circulating exosome in response to Tai Chi (TC) exercise and the possibility of its loaded cargos in mediating the effects of TC training on cognitive function among older adults with amnestic mild cognitive impairment (aMCI). DESIGN, SETTING, AND PARTICIPANTS: This was a multicenter randomized controlled trial. One hundred community-dwelling old adults with aMCI were randomly assigned (1:1) to experimental (n = 50) and control groups (n = 50). INTERVENTION: The experimental group participated in TC exercise 5 times/week, with each session lasting 60 minutes for 12 weeks. Both experimental and control groups received health education every 4 weeks. MEASUREMENTS: The primary outcome was global cognitive function. Neurocognitive assessments, MRI examination, and large-scale proteomics analysis of peripheric exosome were conducted at baseline and after 12-week training. Outcome assessors and statisticians were blinded to group allocation. RESULTS: A total of 96 participants (96%) completed all outcome measurements. TC training improved global cognitive function (adjusted mean difference [MD] = 1.9, 95%CI 0.93-2.87, p <0.001) and memory (adjusted MD = 6.42, 95%CI 2.09-10.74, p = 0.004), increased right hippocampus volume (adjusted MD = 88.52, 95%CI 13.63-163.4, p = 0.021), and enhanced rest state functional connectivity (rsFC) between hippocampus and cuneus, which mediated the group effect on global cognitive function (bootstrapping CIs: [0.0208, 1.2826], [0.0689, 1.2211]) and verbal delay recall (bootstrapping CI: [0.0002, 0.6277]). Simultaneously, 24 differentially expressed exosomal proteins were detected in tandem mass tag-labelling proteomic analysis. Of which, the candidate protein low-density lipoprotein receptor-related protein 1 (LRP1) was further confirmed by parallel reaction monitoring and ELISA. Moreover, the up-regulated LRP1 was both positively associated with verbal delay recall and rsFC (left hippocampus-right cuneus). CONCLUSION: TC promotes LRP1 release via exosome, which was associated with enhanced memory function and hippocampus plasticity in aMCI patients. Our findings provided an insight into potential therapeutic neurobiological targets focusing on peripheric exosome in respond to TC exercise.

The altered hippocampal functional connectivity and serum brain-derived neurotrophic factor level predict cognitive decline in patients with knee osteoarthritis.

Patients with knee osteoarthritis (KOA) often suffer from cognitive decline and increased dementia risk, but the neurobiological mechanisms remain unclear. In this study, we evaluated cognitive performance and collected brain magnetic resonance imaging (MRI) data and blood samples from cognitively normal KOA patients at baseline sessions and reevaluated their cognition after 5 years. We also collected MRI data from matched healthy controls. Results showed that KOA patients exhibited dysregulated functional connectivities between the hippocampus and thalamus/superior frontal gyrus compared with healthy controls. The altered hippocampal functional connectivities were associated with serum brain-derived neurotrophic factor (BDNF) levels and spatial expression of genes enriched in synaptic plasticity. The hippocampus-thalamus functional connectivity was significantly correlated with patients' memory scores. Moreover, the baseline hippocampus-thalamus functional connectivity and BDNF levels significantly predicted the development of cognitive decline in KOA patients in the follow-up session. Our findings provide insight into the neurobiological underpinnings of KOA and cognitive decline.

Joint association of sedentary time and physical activity with abnormal heart rate recovery in young and middle-aged adults.

BACKGROUND: Abnormal heart rate recovery (HRR), representing cardiac autonomic dysfunction, is an important predictor of cardiovascular disease. Prolonged sedentary time (ST) is associated with a slower HRR. However, it is not clear how much moderate-to-vigorous physical activity (MVPA) is required to mitigate the adverse effects of sedentary behavior on HRR in young and middle-aged adults. This study aimed to examine the joint association of ST and MVPA with abnormal HRR in this population. METHODS: A cross-sectional analysis was conducted on 1253 participants (aged 20-50 years, 67.8% male) from an observational study assessing cardiopulmonary fitness in Fujian Province, China. HRR measured via cardiopulmonary exercise tests on a treadmill was calculated as the difference between heart rate at peak exercise and 2 min after exercise. When the HRR was ≤ 42 beats·minute-1 within this time, it was considered abnormal. ST and MVPA were assessed by the IPAQ-LF. Individuals were classified as having a low sedentary time (LST [< 6 h·day-1]) or high sedentary time (HST [≥ 6 h·day-1]) and according to their MVPA level (low MVPA [0-149 min·week-1], medium MVPA [150-299 min·week-1], high MVPA [≥ 300 min·week-1]). Finally, six ST-MVPA groups were derived. Associations between ST-MVPA groups with abnormal HRR incidence were examined using logistic regression models. RESULTS: 53.1% of the young and middle-aged adults had less than 300 min of MVPA per week. In model 2, adjusted for possible confounders (e.g. age, sex, current smoking status, current alcohol consumption, sleep status, body mass index), HST was associated with higher odds of an abnormal HRR compared to LST (odds ratio (OR) = 1.473, 95% confidence interval (CI) = 1.172-1.852). Compared with the reference group (HST and low MVPA), the HST and high MVPA groups have a lower chance of abnormal HRR (OR, 95% CI = 0.553, 0.385-0.795). Compared with individuals with HST and low MVPA, regardless of whether MVPA is low, medium, or high, the odds of abnormal HRR in individuals with LST is significantly reduced (OR, 95% CI = 0.515, 0.308-0.857 for LST and low MVPA; OR, 95% CI = 0.558, 0.345-0.902 for LST and medium MVPA; OR, 95% CI = 0.476, 0.326-0.668 for LST and high MVPA). CONCLUSION: Higher amounts of MVPA appears to mitigate the increased odds of an abnormal HRR associated with HST for healthy young and middle-aged adults.

Electroacupuncture improves vascular cognitive impairment no dementia: A Randomized Clinical Trial.

BACKGROUND: Electroacupuncture (EA) could represent a clinically effective treatment strategy for patients with vascular cognitive impairment no dementia (VCIND). This randomized trial aims to explore the underlying mechanism of EA in VCIND patients through cognitive function assessment and neuroimaging assessment. METHODS: 140 eligible patients with VCIND were recruited and randomly divided into EA group (n = 70) and Control group (n = 70). The Montreal Cognitive Assessment (MoCA), and the Auditory Verbal Learning Test (AVLT), the Stroop color-naming task (STROOP), and the resting-state functional magnetic resonance imaging assessment. The EA group received treatment for 30 min/day, 5 times/week, for 8 weeks. RESULTS: EA intervention could increase the MoCA score and improve the neutral and consistency response of the STROOP test in VCIND patients (P < 0.05). fMRI functional connectivity analysis showed that, after EA, the default mode network (DMN) function of the posterior cingulate gyrus, left middle frontal gyrus, left anterior cingulate gyrus, left and right superior temporal gyrus, right insula, left precentral gyrus and other brain regions were significantly higher than that in the control group. The functional connectivity between the posterior cingulate gyrus-left middle frontal gyrus and the posterior cingulate gyrus-right superior temporal gyrus was positively correlated with cognitive function (P < 0.05). Gray Matter Volume increased in VCIND after EA(P < 0.05). CONCLUSIONS: EA can increase the functional connectivity between posterior cingulate gyrus-other gyri in VCIND patients. The functional connectivity is positively correlated with cognitive function.

Targeting lactate-related cell cycle activities for cancer therapy.

Lactate has long been considered as a metabolic by-product of aerobic glycolysis for cancer. However, more and more studies have shown that lactate can regulate cancer progression via multiple mechanisms such as cell cycle regulation, immune suppression, energy metabolism and so on. A recent discovery of lactylation attracted a lot of attention and is already a hot topic in the cancer field. In this review, we summarized the latest functions of lactate and its underlying mechanisms in cancer. We also included our analysis of protein lactylation in different rat organs and compared them with other published lactylation data. The unresolved challenges in this field were discussed, and the potential application of these new discoveries of lactate-related cell cycle activities for cancer target therapy was speculated.

Computerized Cognitive Training Enhances Episodic Memory by Down-Modulating Posterior Cingulate-Precuneus Connectivity in Older Persons With Mild Cognitive Impairment: A Randomized Controlled Trial.

OBJECTIVE: The neural mechanisms underlying the beneficial effects of a computerized cognitive training (CCT) program for improving episodic memory in older persons with mild cognitive impairment (MCI) remain unclear. This study aimed to use both functional and structural brain changes to elucidate the treatment effects of CCT on enhancing episodic memory. DESIGN, SETTING, AND PARTICIPANTS: Single-blinded, multicenter randomized controlled trial on 60 older adults with MCI in Fuzhou, China. INTERVENTION: Participants were randomly assigned to either an 8-week 24-hour CCT program or a health education program as the control. MEASUREMENTS: Clinical outcomes included changes in scores on the immediate and/or delayed recall subtests of the Chinese auditory verbal learning test (CAVLT) and rey complex figure test (CFT), and changes in gray matter volume and the functional connectivity of the posterior cingulate cortex (PCC) and hippocampus in the Papez circuit on magnetic resonance imaging. RESULTS: Significant group-by-time effects showed greater improvements in both immediate and delayed recall scores of CAVLT and delayed recall scores of Rey CFT in participants receiving the CCT program compared to those in the health education program. Among the CCT participants, seed-based analyses revealed decreases in functional connectivity of the PCC and hippocampus with neural substrates in the parietal and occipital regions. The decreased PCC and precuneus connectivity were found to mediate patients' improvements in immediate recall function. CONCLUSION: An 8-week CCT program was effective for improving episodic memory in older individuals with MCI. The decrease in connectivity originating from the PCC and hippocampus is suggestive of potential plastic changes in the Papez circuit, which could have alleviated the age-related compensatory mechanism. The findings of this study also shed light on expanding the content and extending the frequency and duration of the CCT program in future studies.

Effects of Exercise Training Under Hypoxia versus Normoxia on Cognitive Function in Clinical and Non-Clinical Populations: A Systematic Review and Meta-analysis.

OBJECTIVE: To compare the effects of exercise training under hypoxia versus normoxia on cognitive function in clinical and non-clinical populations. DATA SOURCES: From inception to June 13th, 2022, a systematic search was performed on PubMed, Web of Science, Embase, Scopus, and Cochrane Central Register of Controlled Trials. STUDY SELECTION: Randomized controlled trials comparing the effects of exercise under hypoxic vs normoxic on cognition in clinical and non-clinical populations were included. The systematic search generated 14,894 relevant studies, of which 12 were finally included. DATA EXTRACTION: Two reviewers independently extracted data from included studies. Results were expressed as standardized mean difference (SMD). Each included study was assessed using the Cochrane Risk of Bias 1.0 (RoB1.0) tool. Finally, the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system was used to rate the certainty of evidence for each outcome. DATA SYNTHESIS: Overall, 12 studies with a total of 338 participants met the inclusion criteria. The pooled results suggested that hypoxia exercise had a small but not statistically significant positive effect on overall cognitive function (SMD=0.064, 95% confidence interval (CI): -0.156-0.284, P=.567, very low-certainty evidence), when compared with normoxic exercise. Regarding the domain-specific cognitive functions, there was a medium and significant positive effect on memory (SMD=0.594, 95% CI: 0.068 to 1.120, P=.027, very low-certainty evidence), while effects on visuospatial function (SMD=0.490, 95% CI: -0.030 to 1.010, P=.065, very low-certainty evidence), attention (SMD=0.037, 95% CI: -0.340 to 0.414, P=.847, very low-certainty evidence), executive function (SMD=0.096, 95% CI: -0.268 to 0.460, P=.605, very low-certainty evidence), and processing speed (SMD=-0.145, 95% CI: -0.528 to 0.239, P=.459, very low-certainty evidence) were not statistically significant. CONCLUSIONS: The current pooled results revealed that hypoxic exercise was related to improved cognitive performance. Nevertheless, exercise under hypoxia did not have a significant advantage in cognitive promotion when compared with exercise under normoxia.

Electroacupuncture protective effects after cerebral ischemia are mediated through miR-219a inhibition.

BACKGROUND: Electroacupuncture (EA) is a complementary and alternative therapy which has shown protective effects on vascular cognitive impairment (VCI). However, the underlying mechanisms are not entirely understood. METHODS: Rat models of VCI were established with cerebral ischemia using occlusion of the middle cerebral artery or bilateral common carotid artery. The brain structure and function imaging were measured through animal MRI. miRNA expression was detected by chip and qPCR. Synaptic functional plasticity was detected using electrophysiological techniques. RESULTS: This study demonstrated the enhancement of Regional Homogeneity (ReHo) activity of blood oxygen level-dependent (BOLD) signal in the entorhinal cortical (EC) and hippocampus (HIP) in response to EA treatment. miR-219a was selected and confirmed to be elevated in HIP and EC in VCI but decreased after EA. N-methyl-D-aspartic acid receptor1 (NMDAR1) was identified as the target gene of miR-219a. miR-219a regulated NMDAR-mediated autaptic currents, spontaneous excitatory postsynaptic currents (sEPSC), and long-term potentiation (LTP) of the EC-HIP CA1 circuit influencing synaptic plasticity. EA was able to inhibit miR-219a, enhancing synaptic plasticity of the EC-HIP CA1 circuit and increasing expression of NMDAR1 while promoting the phosphorylation of downstream calcium/calmodulin-dependent protein kinase II (CaMKII), improving overall learning and memory in VCI rat models. CONCLUSION: Inhibition of miR-219a ameliorates VCI by regulating NMDAR-mediated synaptic plasticity in animal models of cerebral ischemia.

An Effective Test (EOmciSS) for Screening Older Adults With Mild Cognitive Impairment in a Community Setting: Development and Validation Study.

BACKGROUND: Early detection of mild cognitive impairment (MCI) symptoms is an important step to its diagnosis and intervention. We developed a new screening test called "Efficient Online MCI Screening System" (EOmciSS) for use in community-dwelling older adults. It is a self-paced cognitive test to be completed within 10 minutes on tablets or smartphones in homes or care centers for older adults. OBJECTIVE: This study aims to test the validity of EOmciSS for identifying community-dwelling older adults with MCI risks. METHODS: Participants (N=827) completed EOmciSS and other screening tests for MCI. The psychometric properties tested were "subscale item difficulty," "discriminative index," "internal consistency," and "construct validity." We also tested between-group discrimination using the cross-validation method in an MCI group and a normal cognitive function (NCF) group. RESULTS: A total of 3 accuracy factors and 1 reaction time factor explained the structure of the 20 item factors. The difficulty level of accuracy factors (ie, "trail making," "clock drawing," "cube copying," "delayed recall") was 0.63-0.99, whereas that of the reaction time factor was 0.77-0.95. The discriminative index of the medium-to-high-difficulty item factors was 0.39-0.97. The internal consistency (Cronbach α) ranged from .41 (for few item factors) to .96. The training data set contained 9 item factors (CC-Acc1, P<.001; CD-Acc1, P=.07; CD-Acc2, P=.06; CD-Acc3, P<.001; TM-Acc4, P=.07; DR-Acc1, P=.03; RS, P=.06; DR-RT1, P=.02; and DR-RT2, P=.05) that were significant predictors for an MCI classification versus NCF classification. Depressive symptoms were identified as significant factors (P<.001) influencing the performance of participants, and were an integral part of our test system. Age (P=.15), number of years of education (P=.18), and proficiency in using an electronic device (P=.39) did not significantly influence the scores nor classification of participants. Application of the MCI/NCF cutoff score (7.90 out of 9.67) to the validation data set yielded an area under the curve of 0.912 (P<.001; 95% CI 0.868-0.955). The sensitivity was 84.9%, specificity was 85.1%, and the Youden index was 0.70. CONCLUSIONS: EOmciSS was valid and reliable for identifying older adults with significant risks of MCI. Our results indicate that EOmciSS has higher sensitivity and specificity than those of the Computer-Administered Neuropsychological Screen for Mild Cognitive Impairment and the Computerized Cognitive Screen. The user interface, online operation, and self-paced format allowed the test system to be operated by older adults or their caregivers in different settings (eg, home or care centers for older adults). Depressive symptoms should be an integral part in future MCI screening systems because they influence the test performance and, hence, MCI risk. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000039411; http://www.chictr.org.cn/showprojen.aspx?proj=62903.

Effect of Electroacupuncture on Short-Chain Fatty Acids in Peripheral Blood after Middle Cerebral Artery Occlusion/Reperfusion in Rats Based on Gas Chromatography-Mass Spectrometry.

Previous fundamental and clinical research has shown that electroacupuncture (EA) at the acupoints of Quchi (LI11) and Zusanli (ST36) can successfully alleviate motor dysfunction following stroke. Additionally, it has been discovered that gut microbiota and their metabolites play an essential role in stroke. However, the relationship between the metabolites of gut microbiota and the efficacy of EA is still unclear. Therefore, the aim of this study was to evaluate the mechanism of EA at LI11 and ST36 in the treatment of motor dysfunction after middle cerebral artery occlusion/reperfusion (MCAO/R) in model rats by comparing the differences and correlation between different short-chain fatty acids (SCFAs) and the recovery of motor function. The results indicated that EA at LI11 and ST36 acupoints enhanced the neurological function, motor function, and infarct volume of MCAO/R rats. The levels of acetic acid, propionic acid, and total SCFAs were considerably lower in the MCAO/R group than in the sham group (P < 0.05). Acetic acid, propionic acid, and total SCFA concentrations were substantially higher in the MCAO/R + EA group than in the MCAO/R group (P < 0.05). Finally, Pearson correlation analysis revealed that the propionic acid concentration was substantially favorably connected with the duration on the rotarod (r = 0.633 and P < 0.05) and highly negatively correlated with the modified neurological severity score (mNSS) (r = -0.698 and P < 0.05) and the percentage of cerebral infarct volume (r = -0.729 and P < 0.05). Taken together, these findings indicate that the increase in propionic acid may be one of the mechanisms and targets of EA at LI11 and ST36 acupoints to improve poststroke motor dysfunction in MCAO/R rats.

The impact of physical activity on blood inflammatory cytokines and neuroprotective factors in individuals with mild cognitive impairment: a systematic review and meta-analysis of randomized-controlled trials.

BACKGROUND: Accumulated evidence has proved that both neuroinflammation and neuroprotection existing at the stage of mild cognitive impairment (MCI) may mediate its progression, which can conversely be modulated by physical activity (PA). However, further research is needed to clarify which factors are involved in that process. OBJECTIVES: To identify the impact of PA on inflammatory cytokines and neuroprotective factors in individuals with MCI. METHODS: Four databases [PubMed, Cochrane Library, Cochrane Library (Trials), Embase and Web of Science Core Collection] were searched from their inception to October 2021 for randomized-controlled trials (RCTs) assessing the biochemical effect of PA on biomarkers in participants with MCI. Pooled effect size was calculated by the standardized mean difference (SMD). RESULTS: A total of 13 RCTs involving 514 participants by reporting 8 inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, -6, -8, -10, -15, C-reactive protein (CRP) and interferon-γ (IFN-γ) and 5 neuroprotective factors (brain-derived neurotrophic factor (BDNF), insulin-like growth factor (IGF-1), vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), irisin] were included. The meta-analysis showed that PA had positive effects on decreasing TNF-α (SMD = - 0.32, 95% CI - 0.58 to 0.07, p = 0.01; I2 = 32%) and CRP (SMD = - 0.68, 95% CI - 1.05 to 0.32, p = 0.0002; I2 = 18%), while significantly improving BDNF (SMD = 0.32, 95% CI 0.09-0.56, p = 0.007; I2 = 42%) and IGF-1 (SMD = 0.42, 95% CI 0.03-0.81, p = 0.03; I2 = 0%). CONCLUSION: PA had a certain effect on inhibiting inflammatory cytokines but promoting neuroprotective factors in individuals with MCI which may provide a possible explanation for the potential molecular mechanism of PA on cognitive improvement.

Fronto-cerebellar connectivity mediating cognitive processing speed.

Processing speed is an important construct in understanding cognition. This study was aimed to control task specificity for understanding the neural mechanisms underlying cognitive processing speed. Forty young adult subjects performed attention tasks of two modalities (auditory and visual) and two levels of task rules (compatible and incompatible). Block-design fMRI captured BOLD signals during the tasks. Thirteen regions of interest were defined with reference to publicly available activation maps for processing speed tasks. Cognitive speed was derived from task reaction times, which yielded six sets of connectivity measures. Mixed-effect LASSO regression revealed six significant paths suggestive of a cerebello-frontal network predicting the cognitive speed. Among them, three are long range (two fronto-cerebellar, one cerebello-frontal), and three are short range (fronto-frontal, cerebello-cerebellar, and cerebello-thalamic). The long-range connections are likely to relate to cognitive control, and the short-range connections relate to rule-based stimulus-response processes. The revealed neural network suggests that automaticity, acting on the task rules and interplaying with effortful top-down attentional control, accounts for cognitive speed.

Common and distinct neural trends of allocentric and egocentric spatial coding: An ALE meta-analysis.

The uniqueness of neural processes between allocentric and egocentric spatial coding has been controversial. The distinctive paradigms used in previous studies for manipulating spatial coding could have attributed for the inconsistent results. This study was aimed to generate converging evidence from previous functional brain imaging experiments for collating neural substrates associated with these two types of spatial coding. An additional aim was to test whether test-taking processes would have influenced the results. We obtained coordinate-based functional neuroimaging data for 447 subjects and performed activation likelihood estimation (ALE) meta-analysis. Among the 28 experiments, the results indicate two common clusters of convergence. They were the right precuneus and the right superior frontal gyrus as parts of the parieto-frontal circuit. Between-type differences were in the parieto-occipital circuit, with allocentric showing convergence in the superior occipital gyrus (SOG) cluster compared with egocentric showing convergence in the middle occipital gyrus (MOG) cluster. Task-specific influences were only found in allocentric spatial coding. Spatial judgment-oriented tasks seem to increase the demands on manipulating spatial relationships among the visual objects, while spatial navigation tasks seem to increase the demands on maintaining object representations. Our findings address the theoretical controversies on spatial coding that both the allocentric and egocentric types are common in their processes mediated by the parieto-frontal network, while unique and additional processes in the allocentric type are mediated by the parieto-occipital network. The positive results on possible task-specific confound offer insights into the future design of spatial tasks for eliciting spatial coding processes.

Cortical Hemodynamic Response Associated with Spatial Coding: A Near-Infrared Spectroscopy Study.

Allocentric and egocentric are two types of spatial coding. Previous studies reported the dorsal attention network's involvement in both types. To eliminate possible paradigm-specific confounds in the results, this study employed fine-grained cue-to-target paradigm to dissociate allocentric (aSC) and egocentric (eSC) spatial coding. Twenty-two participants completed a custom visuospatial task, and changes in the concentration of oxygenated hemoglobin (O2-Hb) were recorded using functional near-infrared spectroscopy (fNIRS). The least absolute shrinkage and selection operator-regularized principal component (LASSO-RPC) algorithm was used to identify cortical sites that predicted the aSC and eSC conditions' reaction times. Significant changes in O2-Hb concentration in the right inferior parietal lobule (IPL) and post-central gyrus regions were common in both aSC and eSC. Results of inter-channel correlations further substantiate cortical activities in both conditions were predominantly over the right parieto-frontal areas. Together with right superior frontal gyrus areas be the reaction time neural correlates, the results suggest top-down attention and response-mapping processes are common to both spatial coding types. Changes unique to aSC were in clusters over the right intraparietal sulcus, right temporo-parietal junction, and left IPL. With the left pre-central gyrus region, be the reaction time neural correlate, aSC is likely to involve more orienting attention, updating of spatial information, and object-based response selection and inhibition than eSC. Future studies will use other visuospatial task designs for testing the robustness of the findings on spatial coding processes.

Electroacupuncture ameliorates learning and memory deficits via hippocampal 5-HT1A receptors and the PKA signaling pathway in rats with ischemic stroke.

Hippocampal 5-HT1A receptors and the PKA signaling pathway have been implicated in learning and memory. This study aimed to investigate whether PKA signaling mediated by 5-HT1A receptors was involved in the electroacupuncture (EA)-mediated learning and memory in a rat model of middle cerebral artery occlusion-induced cognitive deficit (MICD). Compared to no treatment or non-acupoint EA treatment, EA at DU20 and DU24 acupoints improved the neurological deficit of scores, shortened escape latency and increased the frequency of crossing the platform in the Morris water maze test. T2-weighted imaging demonstrated that the MICD rat brain lesions were mainly located in the cortex and hippocampus, and injured volumes were reduced after EA. Furthermore, we found that these behavioral changes were concomitant with the deficit of the 5HT1A and PKA signaling pathways in the hippocampus, as the activation of the 5-HT1A receptor, the reduction of PKA kinase activity, and AMPA and NMDA receptor phosphorylation occurred in the injured hippocampus at Day 14 after MICD. Additionally, EA dramatically elevated the activation of PKA. Moreover, EA significantly increased intracellular calcium concentrations regulated by the activation of NMDA receptors. Therefore, PKA kinase and NMDA receptors mediated by 5-HT1A receptors in the hippocampus might contribute to improving learning and memory during the recovery process following ischemic stroke with an EA intervention.

Disease Stage-Associated Alterations in Learning and Memory through the Electroacupuncture Modulation of the Cortical Microglial M1/M2 Polarization in Mice with Alzheimer's Disease.

Microglia are the primary cells that exert immune function in the central nervous system, and accumulating evidence suggests that microglia act as critical players in the initiation of neurodegenerative disorders, such as Alzheimer's disease (AD). Microglia seemingly demonstrate two contradictory phenotypes in response to different microenvironmental cues, the M1 phenotype and the M2 phenotype, which are detrimental and beneficial to pathogenesis, respectively. Inhibiting the M1 phenotype with simultaneous promoting the M2 phenotype has been suggested as a potential therapeutic approach for cure AD. In this study, we demonstrated that electroacupuncture at the Shenting and Baihui acupoints for 16 weeks could improve learning and memory in the Morris water maze test and reduce amyloid ß-protein in the parietal association cortex and entorhinal cortex in mice with mild and moderate AD. Besides, electroacupuncture at the Shenting and Baihui acupoints not only suppressed M1 marker (iNOS/IL-1ß) expression but also increased the M2 marker (CD206/Arg1) expression in those regions. We propose that electroacupuncture at the Shenting and Baihui acupoints could regulate microglial polarization and decrease Aß plaques to improve learning and memory in mild AD mice.

The modulation effect of non-invasive brain stimulation on cognitive function in patients with mild cognitive impairment: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: To prevent and control dementia, many scholars have focused on the transition stage between normal ageing and dementia, mild cognitive impairment (MCI) which is a key interventional target for dementia. Studies have shown that non-invasive brain stimulation (NIBS) is beneficial to improve cognitive function of MCI patients. However, whether NIBS is conducive to the protection of cognitive ability in MCI patients remains unknown due to limited evidence. The aim of the study was to systematically evaluate the modulation effect of NIBS on cognitive function (global cognitive ability and specific domains of cognition) in patients with MCI. RESULTS: A total of 11 RCTs comprising a total of 367 MCI participants. Meta-analysis showed that NIBS can significantly improve global cognition (n = 271, SMD = 0.94, 95% CI 0.47-1.41, p < 0.0001) and verbal fluency (n = 72, MD = 2.03, 95% CI 0.17-3.88, p = 0.03). However, there was no significant improvement in other domains of cognition. CONCLUSIONS: NIBS has a positive effect on improving global cognitive function and verbal fluency. At the same time, it has a small positive effect on improving executive function. However, these findings should be interpreted carefully due to the limitations of the study.

Different exercise modalities relieve pain syndrome in patients with knee osteoarthritis and modulate the dorsolateral prefrontal cortex: A multiple mode MRI study.

OBJECTIVES: Knee osteoarthritis (KOA) is a common degenerative joint disease with no satisfactory intervention. Recently, both physical and mindfulness exercises have received considerable attention for their implications in KOA pain management, and the dorsolateral prefrontal cortex (DLPFC) has displayed a critical role in pain modulation. This study aimed to comparatively investigate the modulation effects of different exercises using multidisciplinary measurements. METHODS: 140 KOA patients were randomized into Tai Chi, Baduanjin, stationary cycling, or health education control groups for 12 weeks. Knee Injury and Osteoarthritis Outcome Score (KOOS), resting state functional magnetic resonance imaging (fMRI), structural MRI, and serum biomarkers were measured at baseline and at the end of the study. RESULTS: We found: 1) increased KOOS pain subscores (pain reduction) and serum programmed cell death protein 1 (PD-1) levels in the three exercise groups compared to the control group; 2) decreased resting state functional connectivity (rsFC) of the DLPFC-supplementary motor area (SMA) and increased rsFC between the DLPFC and anterior cingulate cortex in all exercise groups compared to the control group; 3) significant associations between DLPFC-SMA rsFC with KOOS pain subscores and serum PD-1 levels at baseline; 4) significantly increased grey matter volume in the SMA in the Tai Chi and stationary cycling groups, and a trend toward significant increase in the Baduanjin group compared to the control group; 5) significant DLPFC rsFC differences among different exercise groups; and 6) that baseline DLPFC-SMA rsFC can predict the effect of mind-body exercise on pain improvement in KOA. CONCLUSION: Our results suggest that different exercises can modulate both common and unique DLPFC (cognitive control) pathways, and altered DLPFC-SMA rsFC is associated with serum biomarker levels. Our findings also highlight the potentials of neuroimaging biomarkers in predicting the therapeutic effect of mind-body exercises on KOA pain.

Modulatory effects of different exercise modalities on the functional connectivity of the periaqueductal grey and ventral tegmental area in patients with knee osteoarthritis: a randomised multimodal magnetic resonance imaging study.

BACKGROUND: Knee osteoarthritis is a prevalent disorder with unsatisfactory treatment options. Both physical and mindful exercises may be able to relieve its pain symptoms. We compared the modulatory effects of different exercise modalities on the periaqueductal grey (PAG) and ventral tegmental area (VTA), which play important roles in descending opioidergic pathways and reward/motivation systems in patients with knee osteoarthritis. METHODS: We recruited and randomised 140 patients into Tai Chi, Baduanjin, stationary cycling, and health education control groups for 12 weeks. Knee injury and Osteoarthritis Outcome Score (KOOS), functional and structural MRI, and blood biomarkers were measured at the beginning and end of the experiment. We used the PAG and VTA as seeds in resting-state functional connectivity (rsFC) analysis. RESULTS: Compared with the control group: (i) all exercises significantly increased KOOS pain sub-scores (pain reduction) and serum programmed death 1 (PD-1) concentrations; (ii) all exercises decreased right PAG rsFC with the medial orbital prefrontal cortex, and the decreased rsFC was associated with improvements in knee pain; and (iii) grey matter volume in the medial orbital prefrontal cortex was significantly increased in all exercise groups. There was also significantly decreased rsFC between the left VTA and the medial orbital prefrontal cortex in the Tai Chi and Baduanjin groups. CONCLUSIONS: Exercise can simultaneously modulate the rsFC of the descending opioidergic pathway and reward/motivation system and blood inflammation markers. Elucidating the shared and unique mechanisms of different exercise modalities may facilitate the development of exercise-based interventions for chronic pain. CLINICAL TRIAL REGISTRATION: ChiCTR-IOR-16009308.