Association between the triglyceride-glucose index and cognitive impairment in China: a community population-based cross-sectional study.

INTRODUCTION: Insulin resistance (IR) is a feature of metabolic syndrome and plays an important role in cognitive impairment (CI). The triglyceride-glucose (TyG) index is a convenient and cost-effective surrogate for assessing IR. This study aimed to assess the association between the TyG index and CI. METHODS: This community population-based cross-sectional study used a cluster-sampling methodology. All participants underwent the education-based Mini-Mental State Examination (MMSE), and those with CI were identified using standard thresholds. The fasting blood triglyceride and glucose levels were measured in the morning, and the TyG index was calculated as ln (½ fasting triglyceride level [mg/dL] × fasting blood glucose level [mg/dL]). Multivariable logistic regression and subgroup analysis were used to assess the relationship between the TyG index and CI. RESULTS: This study included 1484 subjects, of which 93 (6.27%) met the CI criteria. Multivariable logistic regression showed that CI incidence increased by 64% per unit increase in the TyG index (odds ratio [OR] = 1.64, 95% confidence interval [CI]: 1.02-2.63, p = 0.042). CI risk was 2.64-fold higher in the highest TyG index quartile compared to the lowest TyG index quartile (OR = 2.64, 95% CI: 1.19-5.85, p = 0.016). Finally, interaction analysis showed that sex, age, hypertension, and diabetes did not significantly affect the association between the TyG index and CI. CONCLUSION: The present study suggested that an elevated TyG index was associated with a higher CI risk. Subjects with a higher TyG index should manage and treat at an early stage to alleviate the cognitive decline.

Associations among Body Mass Index, Waist-to-Hip Ratio, and Cognitive Impairment Tend to Follow an Opposite Trend and Are Sex Specific: A Population-Based Cross-Sectional Study in a Rural Area of Xi'an, China.

INTRODUCTION: The relationship between obesity and cognitive impairment (CI) is highly heterogeneous in previous studies, which may be due to insufficient consideration of anthropometric indicators and sex. This study compared the cross-sectional relationships among body mass index (BMI), waist-to-hip ratio (WHR), and CI among people aged ≥40 years, and sex-specific relationships were also considered. METHODS: This was a population-based cross-sectional study with a cluster sampling design. CI was defined as a Mini-Mental State Examination score lower than the cutoff value. Multivariate logistic regression was used. BMI and WHR were fitted as both restricted cubic splines and categorical data. Stratified analysis and interaction analysis were performed to explore the sex-specific relationship. RESULTS: A total of 1,792 subjects (40.5% male) were analyzed, and 230 were confirmed to have CI. The relationships among BMI, WHR, and CI were significant (poverall = 0.023, pnonlinear = 0.097; poverall = 0.017, pnonlinear = 0.078, respectively) but exhibited an opposite trend in the total population in the analyses with BMI and WHR as restricted cubic splines. Further categorical analyses showed that subjects with a BMI <23 kg/m2 tended to have a higher risk of CI than those with BMI ≥23 kg/m2 (16.2% vs. 11.8%, p = 0.017; OR = 1.366 [0.969-1.926], p = 0.075), and subjects with a WHR >0.92 had a significantly higher risk of CI than those with a WHR ≤0.92 (11.7% vs. 16.2%, p = 0.011; OR = 1.619 [1.161-2.258], p = 0.005). In addition, the relationship between a low BMI and CI was more significant in males (p = 0.034), while the relationship between a high WHR and CI was more significant in females (p = 0.002). Further studies are needed to confirm the sex differences because of the marginal significance result in the interaction analysis (p = 0.051 for interaction term BMI × sex; p = 0.056 for interaction term WHR × sex). CONCLUSION: The relationships among BMI, WHR, and CI exhibit an opposite trend. A low BMI or high WHR was positively associated with CI, which was more prominent in males for a low BMI and females for a high WHR.

Loganin attenuates neuroinflammation after ischemic stroke and fracture by regulating α7nAChR-mediated microglial polarization.

Fracture in acute stage of ischemic stroke can increase inflammatory response and enhance stroke injury. Loganin alleviates the symptoms of many inflammatory diseases through its anti-inflammatory effect, but its role in ischemic stroke and fracture remains to be explored. Here, mice were handled with permanent middle cerebral artery occlusion (pMCAO) followed by tibial fracture 1 day later to establish a pMCAO+fracture model. Loganin or Methyllycaconitine (MLA, a specific a7nAchR inhibitor) were intragastrically administered 2 or 0.5 h before pMCAO, respectively. And mouse motor function and infarct volume were evaluated 3 days after pMCAO. We found that loganin alleviated the neurological deficit, cerebral infarction volume, and neuronal apoptosis (NeuN+ TUNEL+ ) in mice with pMCAO+fracture. And loganin suppressed pMCAO+fracture-induced neuroinflammation by promoting M2 microglia polarization (Iba1+ CD206+ ) and inhibiting M1 microglia polarization (Iba1+ CD11b+ ). While administration with MLA reversed the protective effect of loganin on pMCAO+fracture-induced neurological deficit and neuroinflammation. Next, LPS was used to stimulate BV2 microglia to simulate pMCAO+fracture-induced inflammatory microenvironment in vitro. Loganin facilitated the transformation of LPS-stimulated BV2 cells from M1 pro-inflammatory state (CD11b+ ) to M2 anti-inflammatory state (CD206+ ), which was antagonized by treatment with MLA. And loganin induced autophagy activation in LPS-stimulated BV2 cells by activating a7nAchR. Moreover, treatment with rapamycin (an autophagy activator) neutralized the inhibitory effect of MLA on loganin induced transformation of BV2 cells to M2 phenotype. Furthermore, BV2 cells were treated with LPS, LPS + loganin, LPS + loganin+MLA, or LPS + loganin+MLA+ rapamycin to obtain conditioned medium (CM) for stimulating primary neurons. Loganin reduced the damage of primary neurons caused by LPS-stimulated BV2 microglia through activating a7nAchR and inducing autophagy activation. In conclusion, loganin played anti-inflammatory and neuroprotective roles in pMCAO + fracture mice by activating a7nAchR, enhancing autophagy and promoting M2 polarization of microglia.

Protocol of End-PSCI trial: a multicenter, randomized controlled trial to evaluate the effects of DL-3-n-butylphthalide on delayed-onset post stroke cognitive impairment.

BACKGROUND: Delayed-onset post stroke cognitive impairment (PSCI) results from secondary neurodegeneration induced by stroke. Whereas targeted prevention or treatment strategies are still missing due to lack of evidences. This trial aims to evaluate the preventive effects of DL-3-n-butylphthalide (NBP) on delayed-onset PSCI. METHODS: Effects of NBP on Delayed-onset Post Stroke Cognitive Impairment (End-PSCI) is a prospective, parallel-group, open-label, multicenter, randomized controlled trial with blinded outcome assessment. Hospital patients with acute cerebral infarction (within 2 weeks of onset) will be randomized into either standard medical therapy group or standard medical therapy combined NBP treatment group (NBP 200 mg, three times per day for 24 weeks). The primary outcome is the difference of incidence of delayed-onset PSCI between two groups. The secondary outcomes include difference of white matter degeneration, cognitive scores and prevalence of early-onset PSCI between two groups. DISCUSSION: End-PSCI trial will provide evidences for NBP preventing delayed-onset PSCI. The secondary outcomes will also provide valuable insights into the pathogenesis of delayed-onset PSCI and mechanism of NBP's actions. TRIAL REGISTRATION: Trialsearch.who.int , ChiCTR2000032555, 2020/5/2, prospectively registered.

Prediction of Alzheimer's disease using multi-variants from a Chinese genome-wide association study.

Previous genome-wide association studies have identified dozens of susceptibility loci for sporadic Alzheimer's disease, but few of these loci have been validated in longitudinal cohorts. Establishing predictive models of Alzheimer's disease based on these novel variants is clinically important for verifying whether they have pathological functions and provide a useful tool for screening of disease risk. In the current study, we performed a two-stage genome-wide association study of 3913 patients with Alzheimer's disease and 7593 controls and identified four novel variants (rs3777215, rs6859823, rs234434, and rs2255835; Pcombined = 3.07 × 10-19, 2.49 × 10-23, 1.35 × 10-67, and 4.81 × 10-9, respectively) as well as nine variants in the apolipoprotein E region with genome-wide significance (P < 5.0 × 10-8). Literature mining suggested that these novel single nucleotide polymorphisms are related to amyloid precursor protein transport and metabolism, antioxidation, and neurogenesis. Based on their possible roles in the development of Alzheimer's disease, we used different combinations of these variants and the apolipoprotein E status and successively built 11 predictive models. The predictive models include relatively few single nucleotide polymorphisms useful for clinical practice, in which the maximum number was 13 and the minimum was only four. These predictive models were all significant and their peak of area under the curve reached 0.73 both in the first and second stages. Finally, these models were validated using a separate longitudinal cohort of 5474 individuals. The results showed that individuals carrying risk variants included in the models had a shorter latency and higher incidence of Alzheimer's disease, suggesting that our models can predict Alzheimer's disease onset in a population with genetic susceptibility. The effectiveness of the models for predicting Alzheimer's disease onset confirmed the contributions of these identified variants to disease pathogenesis. In conclusion, this is the first study to validate genome-wide association study-based predictive models for evaluating the risk of Alzheimer's disease onset in a large Chinese population. The clinical application of these models will be beneficial for individuals harbouring these risk variants, and particularly for young individuals seeking genetic consultation.

Sleep disturbance is associated with mild cognitive impairment: a community population-based cross-sectional study.

BACKGROUND: Sleep is conducive to the elimination of brain metabolites and the recovery of brain function. However, the relationship between sleep disturbance and Mild Cognitive Impairment is not fully been determined. METHODS: This was a community population-based cross-sectional study. A total of 1,443 participants from a village in the suburbs of Xi'an, China were enrolled in 2017. Sleep quality was evaluated using the Pittsburgh sleep quality index (PSQI), and sleep disturbance was defined as a PSQI score > 5. Mini-Mental State Examination (MMSE) was used to assess cognitive function and Mild Cognitive Impairment(MCI) was defined as the MMSE score less than cutoff values and meets the diagnostic criteria. Univariate and multivariate analyses were used to analyze the relationships between sleep disturbance and MCI. RESULTS: Among 1,443 subjects, 69(4.78%) had MCI, and 830 (57.52%) had sleep disturbance. In bivariate analysis, MCI was associated with sleep disturbance (ρ = 0.094, P<0.001). In the binary logistic regression, MCI was positively associated with the sleep disturbance (OR = 2.027, 95%CI = 1.112-3.698, P = 0.021). In the internal constitution of PSQI, MCI was negatively associated with the habitual sleep efficiency (OR = 0.447, 95%CI = 0.299-0.669, P < 0.001). Compared with waking up before or at 7 am, waking up after 7 am (OR = 0.555, 95%CI = 0.309-0.995, P = 0.048), or 8 am (OR = 0.296, 95%CI = 0.097-0.902, P = 0.032) was probably more likely to have normal cognition. However, people who slept more than 8 h a day might be more likely to suffer from MCI (OR = 5.560, 95%CI = 1.419-21.789, P = 0.014). CONCLUSION: Sleep disturbance is associated with Mild Cognitive Impairment. However, the causal relationship between them is not clear. It needs to be further studied.

Chronic ghrelin administration suppresses IKK/NF-κB/BACE1 mediated Aß production in primary neurons and improves cognitive function via upregulation of PP1 in STZ-diabetic rats.

Diabetic rats display cognition impairments accompanied by activation of NF-κB signalling and increased Aß expression. Ghrelin has been suggested to improve cognition in diabetic rats. In this study, we investigated the role of ghrelin on cognition and NF-κB mediated Aß production in diabetic rats. A diabetic rat model was established with streptozotocin (STZ) injection, and diabetic rats were intracerebroventricularly administered with ghrelin or (D-lys3)-GHRP-6 (DG). Our results showed that diabetic rats had cognition impairment in the Morris water maze test, accompanied by the higher expression of Aß in the hippocampus. Western blot analysis showed that diabetic rats exhibited significantly decreased levels of GHSR-1a and protein phosphatase 1 (PP1) in the hippocampus and increased activation of the IKK/NF-κB/BACE1 pathway. Chronic ghrelin administration upregulated hippocampal PP1 expression, suppressed IKK/NF-κB/BACE1 mediated Aß production, and improved cognition in STZ-induced diabetic rats. These effects were reversed by DG. Then, primary rat hippocampal neurons were isolated and treated with high glucose, followed by Ghrelin and DG, PP1 or IKK. Similar to the in vivo results, high glucose suppressed the expression levels of GHSR-1a and PP1, activated the IKK/NF-κB/BACE1 pathway, increased Aß production. Ghrelin suppressed IKK/NF-κB/BACE1 induced Aß production. This improvement was reversed by DG and a PP1 antagonist and was enhanced by the IKK antagonist. Our findings indicated that chronic ghrelin administration can suppress IKK/NF-κB/BACE1 mediated Aß production in primary neurons with high glucose treatment and improve the cognition via PP1 upregulation in diabetic rats.

NDRG4 Alleviates Aß1-40 Induction of SH-SY5Y Cell Injury via Activation of BDNF-Inducing Signalling Pathways.

We explored the functions and mechanisms of N-myc downstream-regulated gene 4 (NDRG4) in an amyloid beta 1-40 induced Alzheimer's disease cell model. The levels of total and phosphorylated Tau protein were significantly up-regulated and cell activity was decreased with increasing Aß1-40 treatment in SH-SY5Y cells. The expression of NDRG4 mRNA and protein levels were significantly decreased that induced by Aß1-40 in these cells. NDRG4 overexpression significantly alleviated Aß1-40-induced SH-SY5Y apoptosis rates and caspases-3/7 activities. Equally, Reactive oxygen species, Mitochondrial membrane potential and Microscale malondialdehyde levels were significantly down-regulated, and Superoxide dismutase activity was increased by NDRG4 overexpression. BDNF protein level and phosphorylation levels of AKT and ERK1/2 were enhanced by NDRG4 overexpression. We also determined that the inhibitory effects of NDRG4 on cell apoptosis and Reactive oxygen species release were partially reversed by BDNF silencing, and by application of the PI3K specific inhibitor (LY294002) or ERK inhibitor (PD98059). These data indicate that NDRG4 attenuates Aß1-40-induced cell apoptosis and Reactive oxygen species release release, as well as oxidative stress injury. These effects may be mediated through BDNF-induced PI3K/AKT and MEK/ERK pathways.

Apolipoprotein E ε4 Allele is Associated With Plasma Amyloid Beta and Amyloid Beta Transporter Levels: A Cross-sectional Study in a Rural Area of Xi'an, China.

OBJECTIVE: The effects of the Apolipoprotein E (ApoE) genotype on peripheral amyloid beta (Aß) and Aß transporter levels are still unclear. Soluble low-density lipoprotein receptor-related protein-1 (sLRP1) and soluble receptor of advanced glycation end products (sRAGE) are the major transporter for Aß, which can prevent plasma Aß from flowing into brain. The aim of this study was to investigate the relationships between the ApoE genotype and plasma Aß, sLRP1, sRAGE levels. DESIGN: Cross-sectional study. SETTING: The committee office of the village. PARTICIPANTS: Residents lived in the village for more than 3 years, aged 40-85 years (n = 1,119, 63.5% women). MEASUREMENTS: Plasma biomarkers include ApoE genotype, Aß, sLRP1, sRAGE, fasting blood-glucose, and blood lipids. General information, medical history, living habits, and cognitive status (cognitive impairment or not) were also collected. RESULTS: After controlling for all possible covariates, multiple linear regression analysis showed that the plasma level of Aß42 was higher and log-transformed sLRP1 was lower in ApoE ε4 carriers than that in noncarriers (ßAß42 = 1.214, 95% confidence interval: 0.105-2.316, pAß42 = 0.031; ßsLRP1 = -0.075, 95% confidence interval: -0.129 to -0.021, psLRP1 = 0.006, respectively). Partial correlation analysis showed that plasma Aß40 was positively correlated with log-transformed sLRP1 and log-transformed sRAGE (rsLRP1 = 0.116, psLRP1 <0.001; rsRAGE = 0.078, psLRP1 = 0.009, respectively). Plasma Aß42 was positively correlated with log-transformed sRAGE (r = 0.072, p = 0.017). CONCLUSION: ApoE ε4 carriers had higher plasma Aß42 levels and lower sLRP1 levels. These data indicated that the ApoE ε4 allele may also contribute to the pathogenesis of Alzheimer's disease through its effects on peripheral Aß42 and sLRP1 levels, but it needs to be further elucidated.

The relationship between blood lipids and plasma amyloid beta is depend on blood pressure: a population-based cross-sectional study.

BACKGROUND: It is believed that deposition of amyloid beta (Aß) in the brain is the central pathological changes of Alzheimer's disease (AD), which triggers a series of pathological processes. However, the relationship between dyslipidemia and AD is uncertain. Considering the peripheral Aß levels are related to brain Aß deposition, we explore the relationships between blood lipids and plasma Aß. METHODS: Participants who lived in the selected village of Xi'an for more than 3 years were enrolled, aged 40-85 years (n = 1282, 37.9% male). Fasting blood lipid, plasma Aß levels, basic information and living habits were measured. Multiple linear regressions were used. RESULTS: In total population, blood lipids were not associated with plasma Aß. After stratified by blood pressure, serum total cholesterol (TC) and low-density lipoprotein (LDL-c) were positively associated with plasma Aß42 levels (ßTC = 0.666, PTC = 0.024; ßLDL-c = 0.743, PLDL-c = 0.011, respectively) in normal blood pressure. LDL-c was negatively associated with plasma Aß40 levels (ß = - 0.986, P = 0.037) in high blood pressure. CONCLUSION: Elevated plasma Aß42 levels are associated with higher TC and LDL-c in normal blood pressure. Elevated plasma Aß40 levels are associated with lower LDL-c in high blood pressure. This indicated that the relationships between blood lipids and plasma Aß were confounded by blood pressure.

The APOE ε4 exerts differential effects on familial and other subtypes of Alzheimer's disease.

INTRODUCTION: The genetic risk effects of apolipoprotein E (APOE) on familial Alzheimer's disease (FAD) with or without gene mutations, sporadic AD (SAD), and normal controls (NC) remain unclear in the Chinese population. METHODS: In total, 15 119 subjects, including 311 FAD patients without PSEN1, PSEN2, APP, TREM2, and SORL1 pathogenic mutations (FAD [unknown]); 126 FAD patients with PSENs/APP mutations (FAD [PSENs/APP]); 7234 SAD patients; and 7448 NC were enrolled. The risk effects of APOE ε4 were analyzed across groups. RESULTS: The prevalence of the APOE ε4 genotype in FAD (unknown), FAD (PSENs/APP), SAD, and NC groups was 56.27%, 26.19%, 36.23%, and 19.54%, respectively. Further, the APOE ε4 positive genotype had predictive power for FAD (unknown) risk (odds ratio: 4.51, 95% confidence interval: 3.57-5.45, P < .001). DISCUSSION: APOE ε4 positive genotype may cause familial aggregation, and the investigation of multiple interventions targeting APOE pathological function to reduce the risk for this disease warrants attention.

Chronic Sleep Restriction Induces Aß Accumulation by Disrupting the Balance of Aß Production and Clearance in Rats.

Amyloid-ß (Aß) plays an important role in Alzheimer's disease (AD) pathogenesis, and growing evidence has shown that poor sleep quality is one of the risk factors for AD, but the mechanisms of sleep deprivation leading to AD have still not been fully demonstrated. In the present study, we used wild-type (WT) rats to determine the effects of chronic sleep restriction (CSR) on Aß accumulation. We found that CSR-21d rats had learning and memory functional decline in the Morris water maze (MWM) test. Meanwhile, Aß42 deposition in the hippocampus and the prefrontal cortex was high after a 21-day sleep restriction. Moreover, compared with the control rats, CSR rats had increased expression of ß-site APP-cleaving enzyme 1 (BACE1) and sAPPß and decreased sAPPα levels in both the hippocampus and the prefrontal cortex, and the BACE1 level was positively correlated with the Aß42 level. Additionally, in CSR-21d rats, low-density lipoprotein receptor-related protein 1 (LRP-1) levels were low, while receptor of advanced glycation end products (RAGE) levels were high in the hippocampus and the prefrontal cortex, and these transporters were significantly correlated with Aß42 levels. In addition, CSR-21d rats had decreased plasma Aß42 levels and soluble LRP1 (sLRP1) levels compared with the control rats. Altogether, this study demonstrated that 21 days of CSR could lead to brain Aß accumulation in WT rats. The underlying mechanisms may be related to increased Aß production via upregulation of the BACE1 pathway and disrupted Aß clearance affecting brain and peripheral Aß transport.

Validation of neuropsychological tests for the China Health and Retirement Longitudinal Study Harmonized Cognitive Assessment Protocol.

OBJECTIVE: To compare and validate neurocognitive tests in the Harmonized Cognitive Assessment Protocol (HCAP) for the China Health and Retirement Longitudinal Study (CHARLS), and to identify appropriate tests to be administered in future waves of CHARLS. METHODS: We recruited 825 individuals from the CHARLS sample and 766 subjects from hospitals in six provinces and cities in China. All participants were administered the HCAP-neurocognitive tests, and their informants were interviewed regarding the respondents' functional status. Trained clinicians administered the Clinical Dementia Rating scale (CDR) to assess the respondents' cognitive status independently. RESULTS: The testing protocol took an average of 58 minutes to complete. Refusal rates for tests of general cognition, episodic memory, and language were less than 10%. All neurocognitive test scores significantly correlated with the CDR global score (correlation coefficients ranged from 0.139 to 0.641). The Mini-Mental State Examination (MMSE), the Health and Retirement Study (HRS) - telephone interview for cognitive status (TICS), community screening instrument for dementia (CSI-D) for respondent, episodic memory and language tests each accounted for more than 20% of the variance in global CDR score (p < 0.001) in bivariate tests. In the CHARLS subsample, age and education were associated with neuropsychological performance across most cognitive domains, and with functional status. CONCLUSION: A brief set of the CHARLS-HCAP neurocognitive tests are feasible and valid to be used in the CHARLS sample and hospital samples. It could be applied in the future waves of the CHARLS study, and it allows estimating the prevalence of dementia in China through the population-based CHARLS.

The gender- and age- dependent relationships between serum lipids and cognitive impairment: a cross-sectional study in a rural area of Xi'an, China.

BACKGROUND: Serum lipids [total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and triglyceride (TG)] are risk factors for stroke, but the relationships between serum lipids and cognitive impairment have not been verified completely. In this study, we studied the relationships between serum lipids and cognitive impairment and explored whether gender and age had effects on the relationships. METHODS: In this cross-sectional study, we collected serum lipids and cognitive function information from 1762 participants (aged 40-85). Univariate analysis, multivariate analysis, and both gender- and age-based stratified multivariate analysis were used. RESULTS: In the entire sample set, there was no significant correlation between serum lipid parameters (TC, LDL-C, HDL-C and TG) and cognitive impairment. In both gender- and age-based stratified multivariate analysis, high serum TC was positively associated with cognitive impairment in the elderly (> 55) male participants (OR = 4.404, 95% CI = 1.264-15.344, p = 0.02), and high serum LDL-C was positively correlated with cognitive impairment in the elderly female subjects (OR = 2.496, 95% CI = 1.057-5.896, p = 0.037), while high serum TG was negatively associated with cognitive impairment in the middle-aged (≤ 55) male participants (OR = 0.157, 95% CI = 0.051-0.484, p = 0.001). CONCLUSIONS: The relationships between serum lipids and cognitive impairment are gender- and age- dependent, with high serum TC and LDL-C may be risk factors of cognitive impairment in the elderly male and female subjects respectively, while high serum TG may be protector of cognitive impairment in the middle-aged male participants.

A Voxel-Based Magnetic Resonance Imaging Morphometric Study of Cerebral and Cerebellar Gray Matter in Patients Under 65 Years with Essential Tremor.

BACKGROUND The aim of this study was to compare the morphological changes in cerebral and cerebellar gray matter in patients with essential tremor under 60-years-of-age, with age-matched and gender-matched normal healthy volunteer control subjects, using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM) analysis. MATERIAL AND METHODS A retrospective, controlled, comparative clinical study included 17 patients with essential tremor, <60 years-of-age, and 17 age-matched and gender-matched healthy volunteer control subjects, recruited between June 2010-July 2012. MRI and VBM analysis were used to compare cerebral and cerebellar gray matter density between groups. The Washington Heights-Inwood Genetic Study of Essential Tremor (WHIGET) rating scale was used to assess tremor severity in the patient group. Clinical and demographic characteristics were recorded for all study participants. RESULTS MRI and VBM analysis showed significant bilateral expansion of the cerebellum, occipital fusiform cortices, right inferior temporal gyrus, and precentral lobes in patients with essential tremor (P<0.005); reduction in gray matter was found in the left parietal lobe. The region of interest (ROI) analysis showed volume enlargement in the thalamus, midbrain, and the precuneus (P<0.005). No significant correlation between changes in gray matter and changes in clinical variables, including age, gender, tremor duration, the activity of daily living (ADL) scale, the mini-mental state examination (MMSE) scale, family history, and tremor severity were found. CONCLUSIONS Predominantly cerebellar gray matter expansion in patients less than 60 years-of-age with essential tremor might be the result of compensation for the decline in cerebellar function.

The cost of Alzheimer's disease in China and re-estimation of costs worldwide.

INTRODUCTION: The socioeconomic costs of Alzheimer's disease (AD) in China and its impact on global economic burden remain uncertain. METHODS: We collected data from 3098 patients with AD in 81 representative centers across China and estimated AD costs for individual patient and total patients in China in 2015. Based on this data, we re-estimated the worldwide costs of AD. RESULTS: The annual socioeconomic cost per patient was US $19,144.36, and total costs were US $167.74 billion in 2015. The annual total costs are predicted to reach US $507.49 billion in 2030 and US $1.89 trillion in 2050. Based on our results, the global estimates of costs for dementia were US $957.56 billion in 2015, and will be US $2.54 trillion in 2030, and US $9.12 trillion in 2050, much more than the predictions by the World Alzheimer Report 2015. DISCUSSION: China bears a heavy burden of AD costs, which greatly change the estimates of AD cost worldwide.

Association between Homocysteine and Cerebral Small Vessel Disease: A Meta-Analysis.

BACKGROUND: This study aimed to evaluate whether elevated homocysteine levels is associated with risk of different subtypes of cerebral small vessel disease (CSVD) by using meta-analysis. MATERIALS AND METHODS: Electronic databases were systematically searched up to April 2018 for collecting the studies reporting homocysteine levels in CSVD or CSVD subtypes. After an inclusion and exclusion criteria, the data was extracted. All data was analyzed using Stata software v.12.0 (Stata Corp LP, College Station, TX). The standardized mean difference (SMD) and 95% confidence interval (CI) were used to compare continuous variables. RESULTS: Eighteen studies met eligibility criteria with 5088 participants (1987 patients with CSVD and 3101 controls) included in the meta-analysis. Meta-analysis revealed that, compared with the controls group, the CSVD group had significantly higher homocysteine levels, with the SMD of .50 and 95% CI (.36-.64). Subgroup analyses suggested white matter lesion had significantly higher levels of homocysteine compared with controls (SMD = .56, 95% CI .39-.73), followed by silent brain infarction (SMD = .33, 95% CI .24-.42) and lacunar infarction (SMD = .17, 95% CI -.06 to .40). CONCLUSIONS: This meta-analysis found that CSVD or CSVD subtypes have a significantly higher homocysteine levels than in controls. Further prospective population-based studies are needed to longitudinally evaluate the association between homocysteine levels and progression of different CSVD subtypes.

Carnosic Acid Prevents Beta-Amyloid-Induced Injury in Human Neuroblastoma SH-SY5Y Cells via the Induction of Autophagy.

Beta-amyloid (Aß), the hallmark protein in Alzheimer's disease (AD), induces neurotoxicity that involves oxidative stress and mitochondrial dysfunction, leading to cell death. Carnosic acid (CA), a polyphenolic diterpene isolated from the herb rosemary (Rosemarinus officinalis), was investigated in our study to assess its neuroprotective effect and underlying mechanism against Aß-induced injury in human neuroblastoma SH-SY5Y cells. We found that CA pretreatment alleviated the Aß25-35-induced loss of cell viability, inhibited both Aß1-42 accumulation and tau hyperphosphorylation, reduced reactive oxygen species generation, and maintained the mitochondrial membrane potential. Moreover, CA increased the microtubule-associated protein light chain 3 (LC3)-II/I ratio and decreased SQSTM1(p62), indicating that CA could induce autophagy. Autophagy inhibitor 3-methyladenine (3-MA) attenuated the neuroprotective effect of CA, suggesting that autophagy was involved in the neuroprotection of CA. It was also observed that CA activated AMP-activated protein kinase (AMPK) but inhibited mammalian target of rapamycin (mTOR). Furthermore, blocking AMPK with si-AMPKα successfully inhibited the upregulation of LC3-II/I, prevented the downregulation of phosphorylation of mTOR and SQSTM1(p62), indicating that CA induced autophagy in SH-SY5Y cells via the activation of AMPK. These results suggested that CA might be a potential agent for preventing AD.

SIRT3 Acts as a Neuroprotective Agent in Rotenone-Induced Parkinson Cell Model.

SIRT3 is a member of Sirtuins family, which belongs to NAD(+) dependent class III histone deacetylases. Emerging evidence suggests that SIRT3 plays a pivotal role in regulating mitochondrial function. Mitochondrial dysfunction is a main pathogenesis of Parkinson's disease (PD). Here, we have investigated the protective effect of SIRT3 for PD cell model. The rotenone-induced human neuroblastoma SH-SY5Y cells damage was used as PD cell model. The lentiviral vectors were used to over-expression or knockdown SIRT3 expression. The cell viability was analyzed using MTT method. The apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were measured by flow cytometer. Superoxide dismutase (SOD) and glutathione (GSH) were detected by using automated microplate reader. The accumulation of α-synuclein was determined by immunofluorescence staining. SIRT3 knockdown significantly worsen rotenone-induced decline of cell viability (p < 0.01) and enhanced cell apoptosis (p < 0.01), exacerbated the decrease of SOD (p < 0.05) and GSH (p < 0.05), and augmented the accumulation of α-synuclein (p < 0.05). While SIRT3 overexpression dramatically increased cell viability (p < 0.01), and decreased cell apoptosis (p < 0.01), prevented the accumulation of α-synuclein (p < 0.05), suppressed the reducing of SOD (p < 0.05) and GSH (p < 0.01), decreased ROS generation (p < 0.05), and alleviated MMP collapse (p < 0.01) induced by rotenone. SIRT3 has neuroprotective effect in PD cell model and could be developed into a therapeutic agent for PD patients.