ABSTRACT
Alzheimer's disease (AD) lacks effective clinical treatments. As the disease progresses, the cerebral glucose hypometabolism that appears in the preclinical phase of AD gradually worsens, leading to increasingly severe brain energy disorders. This review analyzes the brain energy deficit in AD and its etiology, brain energy rescue strategies based on ketone intervention, the effects and mechanisms of IF, the differences in efficacy between IF and ketogenic diet and the duality of IF. The evidence suggests that brain energy deficits lead to the development and progression of AD pathology. IF, which improves brain energy impairments by promoting ketone metabolism, thus has good therapeutic potential for AD.
Subject(s)
Alzheimer Disease , Diet, Ketogenic , Humans , Alzheimer Disease/metabolism , Ketone Bodies/metabolism , Intermittent Fasting , Brain/metabolism , Ketones/metabolismABSTRACT
BACKGROUND: Early diagnosis of lung adenocarcinoma (LUAD), one of the most common types of lung cancer, is very important to improve the prognosis of patients. The current methods can't meet the requirements of early diagnosis. There is a pressing need to identify novel diagnostic biomarkers. Secretory proteins are the richest source for biomarker research. This study aimed to identify candidate secretory protein biomarkers for early diagnosis of LUAD by integrated bioinformatics analysis and clinical validation. METHODS: Differentially expressed genes (DEGs) of GSE31210, gene expression data of early stage of LUAD, were analyzed by GEO2R. Upregulated DEGs predicted to encode secreted proteins were obtained by taking the intersection of the DEGs list with the list of genes encoding secreted proteins predicted by the majority decision-based method (MDSEC). The expressions of the identified secreted proteins in the lung tissues of early-stage LUAD patients were further compared with the healthy control group in mRNA and protein levels by using the UALCAN database (TCGA and CPTAC). The selected proteins expressed in plasma were further validated by using Luminex technology. The diagnostic value of the screened proteins was evaluated by receiver operating characteristic (ROC) analysis. Cell counting kit-8 assay was carried out to investigate the proliferative effects of these screened proteins. RESULTS: A total of 2183 DEGs, including 1240 downregulated genes and 943 upregulated genes, were identified in the GSE31210. Of the upregulated genes, 199 genes were predicted to encode secreted proteins. After analysis using the UALCAN database, 16 molecules were selected for further clinical validation. Plasma concentrations of three proteins, Midkine (MDK), WAP four-disulfide core domain 2 (WFDC2), and C-X-C motif chemokine ligand 14 (CXCL14), were significantly higher in LUAD patients than in healthy donors. The area under the curve values was 0.944, 0.881, and 0.809 for MDK, WFDC2, and CXCL14, 0.962 when combined them. Overexpression of the three proteins enhanced the proliferation activity of A549 cells. CONCLUSIONS: MDK, WFDC2, and CXCL14 were identified as candidate diagnostic biomarkers for early-stage LUAD and might also play vital roles in tumorigenesis.
Subject(s)
Adenocarcinoma of Lung , Chemokines, CXC , Lung Neoplasms , Midkine , WAP Four-Disulfide Core Domain Protein 2 , Humans , Adenocarcinoma of Lung/diagnosis , Adenocarcinoma of Lung/genetics , Chemokines, CXC/genetics , Early Detection of Cancer , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , Midkine/genetics , Biomarkers, Tumor/genetics , WAP Four-Disulfide Core Domain Protein 2/geneticsABSTRACT
Alzheimer's disease (AD) is a progressive and degenerative disorder accompanied by cognitive decline, which could be promoted by mitochondrial dysfunction induced by mitochondrial Ca 2+ (mCa 2+) homeostasis Mitochondrial calcium uniporter (MCU), a key channel of mCa 2+ uptake, may be a target for AD treatment. In the present study, we reveal for the first time that MCU knockdown in hippocampal neurons improves the memory performance of APP/PS1/tau mice through radial arm maze task. Western blot analysis, transmission electron microscopy (TEM), Golgi staining, immunohistochemistry (IHC) and ELISA results demonstrate that MCU knockdown in hippocampal neurons upregulates the levels of postsynaptic density protein 95 (PSD95) and synaptophysin (SYP), and increases the numbers of synapses and dendritic spines. Meanwhile, MCU knockdown in hippocampal neurons decreases the neuroinflammatory response induced by astrogliosis and high levels of IL-1ß and TNF-α, and improves the PINK1-Parkin mitophagy signaling pathway and increases the level of Beclin-1 but decreases the level of P62. In addition, MCU knockdown in hippocampal neurons recovers the average volume and number of mitochondria. These data confirm that MCU knockdown in hippocampal neurons improves the memory performance of APP/PS1/tau mice through ameliorating the synapse structure and function, relieving the inflammation response and recovering mitophagy, indicating that MCU inhibition has the potential to be developed as a novel therapy for AD.
Subject(s)
Alzheimer Disease , Calcium Channels , Memory , Neurons , Animals , Mice , Alzheimer Disease/metabolism , Disease Models, Animal , Hippocampus/metabolism , Mice, Transgenic , Neurons/metabolism , Calcium Channels/geneticsABSTRACT
Prostaglandin G/H synthase 2 (PTGS2) is a rate-limiting enzyme in prostaglandin synthesis. The present study assessed the role of the uterine circadian clock on Ptgs2 transcription in response to steroid hormones during early pregnancy. We demonstrated that the core clock genes (Bmal1, Per2, Nr1d1, and Dbp), Vegf, and Ptgs2, and their encoded proteins, have rhythmic expression in the mouse uterus from days 3.5 to 4.5 (D3.5-4.5) of pregnancy. Progesterone (P4) treatment of cultured uterus endometrial stromal cells (UESCs) isolated from mPer2Luciferase reporter gene knock-in mice on D4 induced a phase shift in PER2::LUCIFERASE oscillations. This P4-induced phase shift of PER2::LUCIFERASE oscillations was significantly attenuated by the P4 antagonist RU486. Additionally, the amplitude of PER2::LUCIFERASE oscillations was increased by estradiol (E2) treatment in the presence of P4. Consistently, the mRNA levels of clock genes (Bmal1 and Per2), Vegf, and Ptgs2 were markedly increased by E2 treatment of UESCs in the presence of P4. Treatment with E2 also promoted prostaglandin E2 (PGE2) synthesis by UESCs. Depletion of Bmal1 in UESCs by small-interfering RNA (siRNA) decreased the transcript levels of clock genes (Nr1d1 and Dbp), Vegf, and Ptgs2 compared with nonsilencing siRNA treatment. Bmal1 knockdown also inhibited PGE2 synthesis. Moreover, the mRNA expression levels of clock genes (Nr1d1 and Dbp), Vegf, and Ptgs2, and their respective proteins were significantly decreased in the uterus of Bmal1-/- mice. Thus, these data suggest that Bmal1 in mice promotes PGE2 synthesis by upregulating Ptgs2 in response to increases in E2 on D4 of pregnancy.NEW & NOTEWORTHY Rhythmic expression of Bmal1 and Ptgs2 was observed in the uterus isolated from D3.5-4.5 of pregnant mice. E2 increased the expression of Bmal1 and Ptg2 in UESCs isolated from mice on D4. The expression of Ptgs2 was significantly decreased in Bmal1-siRNA treated UESCs. Bmal1 knockdown also inhibited PGE2 synthesis. Thus, these data suggest that Bmal1 in mice promotes PGE2 synthesis by upregulating Ptgs2 in response to increases in E2 on D4 of pregnancy.
Subject(s)
ARNTL Transcription Factors/physiology , Cyclooxygenase 2/genetics , Dinoprostone/biosynthesis , Estradiol/blood , ARNTL Transcription Factors/genetics , Animals , Cells, Cultured , Cyclooxygenase 2/metabolism , Estradiol/pharmacology , Female , Gestational Age , Male , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Pregnancy , Progesterone/pharmacology , Transcriptional Activation/drug effects , Uterus/drug effects , Uterus/metabolismABSTRACT
Zearalenone (ZEA), a mycotoxin, is known to impair reproductive capability by disrupting the synthesis and secretion of testosterone by Leydig cells (LCs), although the mechanism is unknown. Robust rhythmicity of circadian clock and steroidogenic genes were identified in LCs. The aim of this study was to examine whether ZEA significantly attenuated the transcription of core clock genes (Bmal1, Dbp, Per2, and Nr1d1) as well as steroidogenic genes (StAR, Hsd3b2, and Cyp11a1) in mouse testis Leydig cell line (TM3). Western blotting confirmed declines in BMAL1, NR1D1, and StAR protein levels. ZEA also suppressed secreted testosterone levels. In primary LCs, isolated from PER2::LUCIFERASE reporter gene knock in mice, ZEA diminished the amplitude of PER2::LUC expression, and induced a phase shift and period extension. In primary LCs, ZEA also suppressed the expression levels of core clock and steroidogenic genes, reduced protein levels of BMAL1, and decreased testosterone secretion. In vivo expression of core clock and steroidogenic genes were reduced in testes of mice exposed to ZEA for 1 week leading to decreased serum testosterone levels. In summary, data suggest that ZEA may impair testosterone synthesis through attenuation of the circadian clock in LCs culminating in reproductive dysfunction in male mammals .
Subject(s)
Circadian Clocks/drug effects , Estrogens, Non-Steroidal/pharmacology , Leydig Cells/drug effects , Testosterone/metabolism , Zearalenone/pharmacology , Animals , Leydig Cells/metabolism , Male , MiceABSTRACT
Sleep exerts important functions in the regulation of cognition and emotion. Recent studies have found that sleep disorder is one of the important risk factors for Alzheimer's disease (AD), but the effects of chronic sleep deprivation on the cognitive functions of AD model mice and its possible mechanism are still unclear. In the present study, 8-month-old male APP/PS1/tau triple transgenic AD model (3xTg-AD) mice and wild type (WT) mice (n = 8 for each group) were subjected to chronic sleep deprivation by using the modified multiple platform method, with 20 h of sleep deprivation each day for 21 days. Then, open field test, elevated plus maze test, sugar water preference test, object recognition test, Y maze test and conditioned fear memory test were performed to evaluate anxiety- and depression-like behaviors, and multiple cognitive functions. In addition, the immunohistochemistry technique was used to observe pathological characteristics in the hippocampus of mice. The results showed that: (1) Chronic sleep deprivation did not affect anxiety- (P = 0.539) and depression-like behaviors (P = 0.874) in 3xTg-AD mice; (2) Chronic sleep deprivation exacerbated the impairments of object recognition memory (P < 0.001), working memory (P = 0.002) and the conditioned fear memory (P = 0.039) in 3xTg-AD mice; (3) Chronic sleep deprivation increased amyloid ß (Aß) deposition (P < 0.001) and microglial activation (P < 0.001) in the hippocampus of 3xTg-AD mice, without inducing abnormal tau phosphorylation and neurofibrillary tangles. These results indicate that chronic sleep deprivation exacerbates the impairments of recognition memory, working memory and conditioned fear memory in 3xTg-AD mice by aggravating Aß deposition and the excessive activation of microglia in the hippocampus.
Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Amyloid beta-Protein Precursor/genetics , Animals , Cognition , Disease Models, Animal , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Presenilin-1 , Sleep Deprivation , tau ProteinsABSTRACT
BACKGROUND: Although advanced non-squamous non-small cell lung cancer (NSCLC) patients have significantly better survival outcomes after pemetrexed based treatment, a subset of patients still show intrinsic resistance and progress rapidly. Therefore we aimed to use a blood-based protein signature (VeriStrat, VS) to analyze whether VS could identify the subset of patients who had poor efficacy on pemetrexed therapy. METHODS: This study retrospectively analysed 72 advanced lung adenocarcinoma patients who received first-line pemetrexed/platinum or combined with bevacizumab treatment. RESULTS: Plasma samples from these patients were analysed using VS and classified into the Good (VS-G) or Poor (VS-P) group. The relationship between efficacy and VS status was further investigated. Of the 72 patients included in this study, 35 (48.6%) were treated with pemetrexed plus platinum and 37 (51.4%) were treated with pemetrexed/platinum combined with bevacizumab. Among all patients, 60 (83.3%) and 12 (16.7%) patients were classified as VS-G and VS-P, respectively. VS-G patients had significantly better median progression-free survival (PFS) (Unreached vs. 4.2 months; P < 0.001) than VS-P patients. In addition, the partial response (PR) rate was higher in the VS-G group than that in the VS-P group (46.7% vs. 25.0%, P = 0.212). Subgroup analysis showed that PFS was also significantly longer in the VS-G group than that in the VS-P group regardless of whether patients received chemotherapy alone or chemotherapy plus bevacizumab. CONCLUSIONS: Our study indicated that VS might be considered as a novel and valid method to predict the efficacy of pemetrexed-based therapy and identify a subset of advanced lung adenocarcinoma patients who had intrinsic resistance to pemetrexed based regimens. However, larger sample studies are still needed to further confirm this result.
ABSTRACT
BACKGROUND: The five-year cumulative incidence rate in patients diagnosed with stage I small-cell lung cancer (SCLC) who were instructed to undergo surgery was from 40 to 60%.The death competition influence the accuracy of the classical survival analyses. The aim of the study is to investigate the mortality of stage I small-cell lung cancer (SCLC) patients in the presence of competing risks according to a proportional hazards model, and to establish a competing risk nomogram to predict probabilities of both cause-specific death and death resulting from other causes. METHODS: The study subjects were patients diagnosed with stage I SCLC according to ICD-O-3. First, the cumulative incidence functions (CIFs) of cause-specific death, as well as of death resulting from other causes, were calculated. Then, a proportional hazards model for the sub-distribution of competing risks and a monogram were constructed to evaluate the probability of mortality in stage I SCLC patients. RESULTS: 1811 patients were included in this study. The five-year probabilities of death due to specific causes and other causes were 61.5 and 13.6%, respectively. Tumor size, extent of tumor, surgery, and radiotherapy were identified as the predictors of death resulting from specific causes in stage I SCLC. The results showed that surgery could effectively reduce the cancer-specific death, and the one-year cumulative incidence dropped from 34.5 to 11.2%. Like surgery, chemotherapy and radiotherapy improved the one-year survival rate. CONCLUSIONS: We constructed a predictive model for stage I SCLC using the data from the SEER database. The proportional sub-distribution models of competing risks revealed the predictors of death resulting from both specific causes and other causes. The competing risk nomogram that we built to predict the prognosis showed good reliability and could provide beneficial and individualized predictive information for stage I SCLC patients.
Subject(s)
Cause of Death , Lung Neoplasms/mortality , Nomograms , Small Cell Lung Carcinoma/mortality , Aged , Female , Follow-Up Studies , Humans , Lung Neoplasms/diagnosis , Lung Neoplasms/therapy , Male , Middle Aged , Neoplasm Staging , Pneumonectomy , Prognosis , Proportional Hazards Models , Reproducibility of Results , Risk Assessment/methods , Risk Assessment/statistics & numerical data , SEER Program/statistics & numerical data , Small Cell Lung Carcinoma/diagnosis , Small Cell Lung Carcinoma/therapy , Survival Rate , Treatment OutcomeABSTRACT
BACKGROUND: This study aimed to establish a novel nomogram prognostic model to predict death probability for non-small cell lung cancer (NSCLC) patients who received surgery.. METHODS: We collected data from the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute in the United States. A nomogram prognostic model was constructed to predict mortality of NSCLC patients who received surgery. RESULTS: A total of 44,880 NSCLC patients who received surgery from 2004 to 2014 were included in this study. Gender, ethnicity, tumor anatomic sites, histologic subtype, tumor differentiation, clinical stage, tumor size, tumor extent, lymph node stage, examined lymph node, positive lymph node, type of surgery showed significant associations with lung cancer related death rate (P < 0.001). Patients who received chemotherapy and radiotherapy had significant higher lung cancer related death rate but were associated with significant lower non-cancer related mortality (P<0.001). A nomogram model was established based on multivariate models of training data set. In the validation cohort, the unadjusted C-index was 0.73 (95% CI, 0.72-0.74), 0.71 (95% CI, 0.66-0.75) and 0.69 (95% CI, 0.68-0.70) for lung cancer related death, other cancer related death and non-cancer related death. CONCLUSIONS: A prognostic nomogram model was constructed to give information about the risk of death for NSCLC patients who received surgery.
Subject(s)
Carcinoma, Non-Small-Cell Lung/therapy , Lung Neoplasms/therapy , Nomograms , Pneumonectomy , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Chemoradiotherapy, Adjuvant/statistics & numerical data , Female , Follow-Up Studies , Humans , Lung/pathology , Lung/surgery , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Risk Factors , SEER Program/statistics & numerical data , Survival Rate , United States/epidemiology , Young AdultABSTRACT
Alzheimer's disease (AD) is a neurodegenerative disease that severely affects the health and lifespan of the elderly worldwide. Recently, the correlation between AD and type 2 diabetes mellitus (T2DM) has received intensive attention, and a promising new anti-AD strategy is the use of anti-diabetic drugs. Oxyntomodulin (Oxm) is a peptide hormone and growth factor that acts on neurons in the hypothalamus. OXM activates glucagon-like peptide 1 (GLP-1) and glucagon (Gcg) receptors, facilitates insulin signaling and has neuroprotective effects against Aß1-42-induced cytotoxicity in primary hippocampal neurons. Here, we tested the effects of the protease-resistant analogue (D-Ser2)Oxm on spatial memory and synaptic plasticity and the underlying molecular mechanisms in the APP/PS1 transgenic mouse model of AD. The results showed that (D-Ser2)Oxm not only alleviated the impairments of working memory and long-term spatial memory, but also reduced the number of Aß plaques in the hippocampus, and reversed the suppression of hippocampal synaptic long-term potentiation (LTP). Moreover, (D-Ser2)Oxm administration significantly increased p-PI3K/p-AKT1 expression and decreased p-GSK3ß levels in the hippocampus. These results are the first to show an in vivo neuroprotective role of (D-Ser2)Oxm in APP/PS1 mice, and this role involves the improvement of synaptic plasticity, clearance of Aß and normalization of PI3K/AKT/GSK3ß cell signaling in the hippocampus. This study suggests that (D-Ser2)Oxm holds promise for the prevention and treatment of AD.
Subject(s)
Alzheimer Disease/pathology , Glucagon-Like Peptide 1/agonists , Neuronal Plasticity/drug effects , Oxyntomodulin/pharmacology , Receptors, Glucagon/agonists , Spatial Memory/drug effects , Alzheimer Disease/drug therapy , Alzheimer Disease/genetics , Amyloid beta-Protein Precursor/genetics , Animals , Disease Models, Animal , Glucagon-Like Peptide 1/pharmacology , Hippocampus/drug effects , Insulin/metabolism , Long-Term Potentiation/drug effects , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neuroprotective Agents/pharmacology , Oxyntomodulin/therapeutic use , Presenilin-1/geneticsABSTRACT
Cognitive decline, memory impairment and circadian rhythm disturbance are iconic manifestations of Alzheimer's disease (AD). APPswe/PS1dE9 (APP/PS1) mice, a model of AD, show deficits in multiple learning and memory abilities, synaptic plasticity, and behavioral circadian rhythm, but whether circadian differences in cognitive performance and synaptic plasticity could be affected in AD remain unclear. Here, the cognitive behaviors of 6-month-old APP/PS1 mice were assessed by multiple behavior tests in the rest phase (light period) or active phase (dark period) of the day. The possible electrophysiological mechanism was subsequently investigated by in vivo hippocampal long-term potentiation (LTP) recording, and the locomotor activity rhythm of the mice was detected using wheel-running activities. Compared to wild-type (WT) mice, APP/PS1 mice exhibited long-term spatial memory impairment and in vivo hippocampal LTP suppression. In addition, in APP/PS1 mice, circadian differences in new object recognition memory and LTP were lost, and the circadian difference in long-term spatial memory was decreased, accompanied by a less robust locomotor activity rhythm. These results indicate that the loss of circadian differences in new object recognition memory and the decrease in the circadian difference in long-term spatial memory in APP/PS1 mice, which are closely associated with the loss of the circadian difference in LTP and less robust locomotor activity, might occur early in the course of AD.
Subject(s)
Amyloid beta-Protein Precursor , Circadian Rhythm/physiology , Cognitive Dysfunction/metabolism , Maze Learning/physiology , Neuronal Plasticity/physiology , Presenilin-1 , Amyloid beta-Protein Precursor/genetics , Animals , Cognition/physiology , Cognitive Dysfunction/genetics , Cognitive Dysfunction/psychology , Long-Term Potentiation , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Presenilin-1/geneticsABSTRACT
Type 2 diabetes mellitus (T2DM) is an important risk factor for Alzheimer's disease (AD). Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) have been identified to be effective in T2DM treatment and neuroprotection. In this study, we further explored the effects of a novel unimolecular GLP-1/GIP/Gcg triagonist on the cognitive behavior and cerebral pathology in the 7-month-old triple transgenic mouse model of AD (3xTg-AD), and investigated its possible electrophysiological and molecular mechanisms. After chronic administration of the GLP-1/GIP/Gcg triagonist (10 nmol/kg bodyweight, once daily, i.p.) for 30 days, open field, Y maze and Morris water maze tests were performed, followed by in vivo electrophysiological recording, immunofluorescence and Western blotting experiments. We found that the chronic treatment with the triagonist could improve long-term spatial memory of 3xTg-AD mice in Morris water maze, as well as the working memory in Y maze task. The triagonist also alleviated the suppression of long-term potentiation (LTP) in the CA1 region of hippocampus. In addition, the triagonist significantly reduced hippocampal pathological damages, including amyloid-ß (Aß) and phosphorylated tau aggregates, and upregulated the expression levels of S133 p-CREB, T286 p-CAMKII and S9 p-GSK3ß in the hippocampus of the 3xTg-AD mice. These results demonstrate for the first time that the novel GLP-1/GIP/Gcg triagonist is efficacious in ameliorating cognitive deficits and pathological damages of 3xTg-AD mice, suggesting that the triagonist might be potentially beneficial in the treatment of AD.
Subject(s)
Alzheimer Disease/drug therapy , Cognition Disorders/drug therapy , Glucagon-Like Peptide 1/agonists , Neuroprotective Agents/pharmacology , Receptors, Gastrointestinal Hormone/agonists , Receptors, Glucagon/agonists , Alzheimer Disease/pathology , Alzheimer Disease/psychology , Animals , Blood Glucose/drug effects , Body Weight/drug effects , Cognition Disorders/etiology , Cognition Disorders/pathology , Disease Models, Animal , Female , Gene Expression/drug effects , Hippocampus/drug effects , Hippocampus/pathology , Long-Term Potentiation/drug effects , Male , Memory/drug effects , Mice, Inbred C57BL , Mice, Transgenic , Nootropic Agents/pharmacologyABSTRACT
Type 2 diabetes mellitus (T2DM) has been identified as a high risk factor for Alzheimer's disease (AD). The impairment of insulin signaling has been found in AD brain. Glucagon-like peptide-1 (GLP-1) is an incretin hormone, normalises insulin signaling and acts as a neuroprotective growth factor. We have previously shown that the long-lasting GLP-1 receptor (GLP-1R) agonist lixisenatide plays an important role in memory formation, synaptic plasticity and cell proliferation of rats. In the follow-up study, we analysed the neuroprotective effect and mechanism of lixisenatide, injected for 60 days at 10 nmol/kg i.p. once daily in APP/PS1/tau female mice and C57BL/6J female mice (as control) aged 12 month. The results showed that lixisenatide could reduce amyloid plaques, neurofibrillary tangles and neuroinflammation in the hippocampi of 12-month-old APP/PS1/tau female mice; activation of PKA-CREB signaling pathway and inhibition of p38-MAPK might be the important mechanisms in the neuroprotective function of lixisenatide. The study demonstrated that GLP-1R agonists such as lixisenatide might have the potential to be developed as a novel therapy for AD.
Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Encephalitis/drug therapy , Encephalitis/metabolism , Neurofibrillary Tangles/drug effects , Peptides/administration & dosage , Alzheimer Disease/pathology , Amyloid beta-Protein Precursor/genetics , Animals , Dose-Response Relationship, Drug , Encephalitis/pathology , Female , Glucagon-Like Peptide-1 Receptor/agonists , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neurofibrillary Tangles/metabolism , Neurofibrillary Tangles/pathology , Neuroprotective Agents/administration & dosage , Treatment OutcomeABSTRACT
The specific loss of cholinergic neurons and the progressive deficits of cognitive function are the most primary characteristics of Alzheimer's disease (AD). Although the neurotoxicity of amyloid ß protein (Aß) in AD has been investigated extensively, it is still unclear whether the Aß aggregated in the medial septum (MS), a major cholinergic nucleus projecting to the hippocampus, could affect hippocampal synaptic plasticity and further impair the memory behaviors. The present study investigated the effects of Aß injection into the MS on hippocampal long-term potentiation (LTP) and cognitive behaviors of rats by using Morris water maze (MWM), Y maze and in vivo hippocampal LTP recording. The effects of kainic acid (KA), an agent with specific neurotoxicity to GABAergic neurons, were also observed. The results showed that: (1) Intra-MS injection of Aß25-35, not KA, impaired spatial learning and memory of rats in classical and reversal MWM tests; (2) Both Aß25-35 and KA impaired novelty-seeking behavior of rats in Y maze; (3) Intra-MS injection of Aß25-35, not KA, suppressed in vivo hippocampal LTP in the CA1 region of rats; (4) Both Aß25-35 and KA did not affect the motor ability in behavioral tests and the hippocampal paired-pulse facilitation (PPF) in electrophysiological recording. These results indicate that intra-MS injection of Aß could impair spatial memory, cognitive flexibility and exploratory motivation, as well as hippocampal LTP in rats, suggesting that the cholinergic neurons in the MS and the septo-hippocampal projection could be important targets of neurotoxic Aß, and the specific damage of cholinergic neurons in the MS is likely responsible for the impairments of hippocampal synaptic plasticity and cognitive function in AD.
Subject(s)
Amyloid beta-Peptides/adverse effects , Cognition , Hippocampus/physiopathology , Long-Term Potentiation , Peptide Fragments/adverse effects , Alzheimer Disease , Animals , Kainic Acid/adverse effects , Maze Learning , Memory Disorders , Neuronal Plasticity , Rats , Spatial Learning , Spatial MemoryABSTRACT
Although appropriate exercise is beneficial for enhancing brain functions, high-intensity exercise (HIE)-induced cognitive dysfunction is causing more and more concerns nowadays. In the present study, we observed the effects of high-intensity treadmill running on the spatial learning of the adult Sprague Dawley male rats in Y-maze (n = 16 per group), and investigated its possible electrophysiological and molecular mechanisms by examining in vivo hippocampal long-term potentiation (LTP), central inflammatory responses, and JNK/p38/ERK signal pathway. The Y-maze active avoidance test showed that high-intensity treadmill running impaired spatial learning ability of rats, with increased error times and prolonged training time in recognizing safety condition. Associated with the cognitive dysfunction, the induction and maintenance of hippocampal LTP were also impaired by the HIE. Furthermore, accompanied by elevated levels of inflammatory factors IL-1ß, TNF-α, and iNOS, overactivation of microglia and astrocytes was also found in the CA1 region of hippocampus in the excessive exercise group, indicating an inflammatory response induced by HIE. In addition, Western blot assay showed that the phosphorylation of JNK/p38/ERK proteins was enhanced in the exercise group. These results suggest that exercise stress-induced neuronal inflammatory responses in the hippocampus are associated with HIE-induced cognitive deficits, which may be involved in the upregulation of the JNK/p38/ERK pathway. © 2016 Wiley Periodicals, Inc.
Subject(s)
Cognition Disorders/etiology , Cognition Disorders/pathology , Exercise Test/adverse effects , Hippocampus/physiopathology , Inflammation/etiology , Neuronal Plasticity/physiology , Physical Conditioning, Animal/adverse effects , Animals , Calcium-Binding Proteins/metabolism , Cytokines/genetics , Cytokines/metabolism , Electric Stimulation , Glial Fibrillary Acidic Protein/metabolism , Inflammation/metabolism , Male , Maze Learning/physiology , Microfilament Proteins/metabolism , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/physiology , p38 Mitogen-Activated Protein Kinases/genetics , p38 Mitogen-Activated Protein Kinases/metabolismABSTRACT
Alzheimer's disease (AD) is a progressively neurodegenerative disorder, which seriously affects human health but is still irreversible up to now. Recent studies indicate that type 2 diabetes mellitus (T2DM) is an important risk factor for AD, and the drugs used for treatment of T2DM have shown some neuroprotective effects in the treatment of AD. Glucagon-like peptide-1 (GLP-1)/ glucose-dependent insulinotropic polypeptide (GIP)/glucagon (Gcg) receptor Triagonist is a new monomeric polypeptide equally activating the GLP-1/GIP/Gcg receptors, which is built on the basis of GLP-1/Gcg receptor coagonist core sequence, and incorporated with partial amino acids of GIP. Recently, the Triagonist has been reported to be effective in alleviating diabetic complications in rodent models of obesity. The present study observed for the first time the cognitive improvement effects of the Triagonist in the triple-transgenic AD mice (3xTg-AD) by using multiple behavioral techniques, and explored its probable molecular mechanisms using ELISA and Western blot. The results showed that the chronic treatment with the Triagonist (i.p.) significantly reversed the impairments in working memory of 3xTg-AD mice, with an obvious increase in the percentage of correct spontaneous alternation in the Y maze; the Triagonist treatment also improved long-term spatial memory and re-learning ability of 3xTg-AD mice in classical Morris water maze and reverse water maze tests, with decreased escape latency in under water platform tests and increased swimming time in probe tests. ELISA and Western blot experiments showed that the Triagonist up-regulated the levels of cAMP, PKA and p-CREB in the hippocampus of 3xTg-AD mice. These results indicate that GLP-1/GIP/Gcg receptor Triagonist can improve the cognitive behaviors in 3xTg-AD mice, and the up-regulation of hippocampal cAMP/PKA/CREB signal pathway may mediate the neuroprotection of the Triagonist, suggesting that the GLP-1/GIP/Gcg receptor Triagonist may be a novel therapeutic strategy for the treatment of AD.
Subject(s)
Alzheimer Disease/physiopathology , Cognition , Glucagon-Like Peptide-1 Receptor/agonists , Peptides/pharmacology , Receptors, Gastrointestinal Hormone/agonists , Receptors, Glucagon/agonists , Animals , Diabetes Mellitus, Type 2/complications , Hippocampus/metabolism , Mice , Mice, Transgenic , Neuroprotective Agents/pharmacologyABSTRACT
OBJECTIVE: Although superior clinical benefits of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in the treatment of advanced non-small-cell lung cancer (NSCLC) had been reported, the survival difference between exon 19 deletion (Del19) and exon 21 Leu858Arg substitution (L858R) remains controversial. The purpose of this study is to investigate the differences in progression-free survival (PFS) and overall survival (OS) between different EGFR mutant subtypes among advanced NSCLC patients receiving gefitinib. METHODS: There were 204 advanced NSCLC patients with EGFR mutations treated with gefitinib were enrolled in this retrospective cohort study. Patients were divided into the EGFR Del19 group and the L858R mutated group according to their mutant subtype. Propensity score matching (PSM) was conducted by using a nearest-neighbor algorithm (1:1) to adjust for demographical and clinical covariates. Survival curves were constructed with the Kaplan-Meier method and compared by using the log-rank test. RESULTS: The PFS in Del19 group was similar to that in the L858R group [before PSM 8.6 vs. 7.2 months, P=0.072; after PSM 7.3 vs. 7.2 months, P=0.155]. No differences were detected in OS between the L858R and the Del19 group (before PSM 17.8 vs. 13.1 months, P=0.253; after PSM 16.9 vs. 13.1 months, P=0.339). The Del19 group was significantly younger compared with the L858R mutation group in age (P=0.015). CONCLUSIONS: No significant difference was found in the PFS or OS between the Del19 and L858R mutant NSCLC patients receiving gefitinib. The age gap might contribute to the survival differences between Del19 and L858R groups. PSM is of important value to the elimination of potential bias.
ABSTRACT
Circulating tumor cells (CTCs) enter peripheral blood from primary tumors and seed metastases. The genome sequencing of CTCs could offer noninvasive prognosis or even diagnosis, but has been hampered by low single-cell genome coverage of scarce CTCs. Here, we report the use of the recently developed multiple annealing and looping-based amplification cycles for whole-genome amplification of single CTCs from lung cancer patients. We observed characteristic cancer-associated single-nucleotide variations and insertions/deletions in exomes of CTCs. These mutations provided information needed for individualized therapy, such as drug resistance and phenotypic transition, but were heterogeneous from cell to cell. In contrast, every CTC from an individual patient, regardless of the cancer subtypes, exhibited reproducible copy number variation (CNV) patterns, similar to those of the metastatic tumor of the same patient. Interestingly, different patients with the same lung cancer adenocarcinoma (ADC) shared similar CNV patterns in their CTCs. Even more interestingly, patients of small-cell lung cancer have CNV patterns distinctly different from those of ADC patients. Our finding suggests that CNVs at certain genomic loci are selected for the metastasis of cancer. The reproducibility of cancer-specific CNVs offers potential for CTC-based cancer diagnostics.
Subject(s)
DNA Copy Number Variations/genetics , Genome, Human/genetics , Lung Neoplasms/genetics , Neoplasm Metastasis/genetics , Neoplastic Cells, Circulating/chemistry , Base Sequence , Cluster Analysis , Exome/genetics , Gene Library , Humans , Lung Neoplasms/diagnosis , Molecular Sequence Data , Pathology, Molecular/methods , Precision Medicine/methods , Sequence Analysis, DNAABSTRACT
Aggregation of amyloid [Formula: see text] protein (A[Formula: see text] and progressive loss of memory are the main characteristics of Alzheimer's disease (AD). It is noteworthy that approximately 40% of AD patients have depressive symptom. The close correlation between cognitive deficits and mental depression suggests a possibility that antidepression treatment might be beneficial to cognitive improvement in AD. The present study, by using tail-suspension test (TST), forced swimming, alternative electro-stimulus Y maze test and immunohistochemistry, examined the neuroprotective effects of desipramine, a newer generation tricyclic antidepressants (TCA), and investigated its possible molecular mechanism. The results showed that: (1) intra-hippocampal injection of A[Formula: see text] induced depression-like behavior and associative learning deficits in mice, with an increased mean immobility time in tail-suspension and forced swimming test and an increased mean error times in Y maze test; (2) after treatment with desipramine (10[Formula: see text]mg/kg, i.p.), the average immobility time significantly decreased, from [Formula: see text][Formula: see text]s in A[Formula: see text] group to [Formula: see text][Formula: see text]s in A[Formula: see text] plus desipramine group ([Formula: see text]) in TST and from [Formula: see text][Formula: see text]s to [Formula: see text][Formula: see text]s ([Formula: see text] or 9, [Formula: see text]) in forced swimming test, respectively;the mean error times of mice in Y maze test also significantly decreased, from [Formula: see text] in A[Formula: see text] group to [Formula: see text] in A[Formula: see text] plus desipramine group ([Formula: see text], [Formula: see text]); (3) desipramine administration significantly prevented against A[Formula: see text]-induced down-regulation of phosphorylated cAMP response element binding protein (p-CREB) in the hippocampus. These results indicate that A[Formula: see text] could concurrently mimic the depression-like behavior and working memory disorder in mice, while desipramine could effectively reverse both the deficits induced by A[Formula: see text]. The neuroprotection of desipramine may be involved in the up-regulation of p-CREB level in the hippocampus of mice.
Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/psychology , Antidepressive Agents, Tricyclic/pharmacology , Cyclic AMP Response Element-Binding Protein/metabolism , Desipramine/pharmacology , Nootropic Agents/pharmacology , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amyloid beta-Peptides/toxicity , Animals , Depressive Disorder/drug therapy , Depressive Disorder/metabolism , Depressive Disorder/pathology , Disease Models, Animal , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/pathology , Male , Maze Learning/drug effects , Maze Learning/physiology , Memory, Short-Term/drug effects , Memory, Short-Term/physiology , Mice , Motor Activity/drug effects , Motor Activity/physiology , Peptide Fragments/toxicity , Phosphorylation/drug effects , Random Allocation , Up-Regulation/drug effectsABSTRACT
The accumulation and neurotoxicity of amyloid ß protein (Aß) in the brain is one of major pathological hallmarks of Alzheimer's disease (AD). The effective drugs against Aß have been still deficient up to now. According to a most recent study, (D-Ser2) Oxm, a new antidiabetic drug, not only improves the disorders in plasma glucose and insulin in type 2 diabetes mellitus (T2DM) rats, but also exerts positive effects on hippocampal neurogenesis and synaptogenesis. However, it is still unclear whether (D-Ser2)Oxm can directly protect cultured neurons against Aß1-42-induced cytotoxicity. In the present study, we investigated the neuroprotective effects of (D-Ser2)Oxm on the cultured primary hippocampal neurons by testing the cell viability, neuronal apoptosis, mitochondrial membrane potential and intracellular calcium concentration. The results showed that treatment with (D-Ser2)Oxm effectively reversed Aß1-42-induced decline in cell viability (P < 0.001), and this protective effect could be inhibited by the pretreatment with exendin(9-39), a GLP-1 receptor blocker. (D-Ser2)Oxm treatment also decreased Aß1-42-induced neuronal early apoptosis and down-regulated apoptotic protein caspase3. Meantime, (D-Ser2)Oxm treatment inhibited Aß1-42-induced [Ca(2+)]i elevation, mitochondrial membrane potential depolarization, and glycogen synthase kinase-3ß (GSK3ß) activation. These results suggest that (D-Ser2)Oxm can protect hippocampal neurons against Aß1-42-induced cytotoxicity and this effect may be related to activation of GLP-1 receptors, regulation of intracellular calcium homeostasis and stabilization of mitochondrial membrane potential.