Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 50
Filter
Add more filters










Publication year range
1.
Am Surg ; : 31348241257464, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38835213

ABSTRACT

BACKGROUND: This study aimed to evaluate the effectiveness and safety of 2D laparoscopy vs 3D laparoscopy for the treatment of colorectal cancer. METHODS: A literature search was conducted through PubMed, Web of Science, and Embase from their inception to January 2024. Studies investigating different outcomes of colorectal surgery were included. Results are presented as odds ratios (ORs) or mean differences (MDs) with 95% confidence intervals (CIs). The protocol for this review has been registered on PROSPERO (CRD42024504902). RESULTS: A total of 10 publications were retrieved in this article. The 3D group is associated with a significant improvement in intraoperative blood loss (MD = -8.04, 95% CI = -14.18 to -1.89, P = 0.01, I2 = 55%), operative time (MD = -17.33, 95% CI = -29.15 to -5.51, P = 0.004, I2 = 90%), and postoperative hospital stay (MD = -0.23, 95% CI = -0.43 to -0.04, P = 0.02, I2 = 48%) compared to that of patients treated in the 2D group, particularly for rectal cancer patients above three results (MD = -10.36, 95% CI = -15.00 to -5.73, P < 0.001, I2 = 0%), (MD = -18.85, 95% CI = -34.88 to -2.82, P = 0.02, I2 = 57%), and (MD = -0.93, 95% CI = -1.53 to -0.34, P = 0.002, I2 = 0%), respectively. There was no significant statistical difference in the time of pass flatus (MD = -0.14, 95% CI = -0.49 to 0.21, P = 0.44, I2 = 79%) and the number of dissected lymph nodes (MD = 0.36, 95% CI = -0.49 to 1.21, P = 0.41, I2 = 45%), but the 3D group had an earlier postoperative pass flatus for rectal cancer patients (MD = -0.46, 95% CI = -0.66 to -0.27, P<0.001, I2 = 0%) and the more number of dissected lymph nodes for colon cancer patients (MD = 1.54, 95% CI = 0.05 to 3.03, P = 0.04, I2 = 69%) than the 2D group. There was no significant difference in postoperative overall complication (OR = 0.94, 95% CI = 0.67 to 1.31, P = 0.71, I2 = 0%) and anastomotic leakage (OR = 0.93, 95% CI = 0.48 to 1.80, P = 0.83, I2 = 0%) in the two groups, regardless of rectal cancer and colon surgery patients. CONCLUSION: This meta-analysis demonstrates that 3D laparoscopy could reduce the amount of blood loss, accelerate postoperative pass flatus, and shorten the operation time and postoperative hospital stay over 2D for radical rectal cancer surgery, without obvious advantage for radical colon cancer surgery. Moreover, 3D laparoscopy increases the number of dissected lymph nodes for radical colon cancer surgery but may not be observed in rectal cancer surgery.

3.
Mol Pharmacol ; 92(3): 188-192, 2017 09.
Article in English | MEDLINE | ID: mdl-28404616

ABSTRACT

Pharmacology is the science that investigates the interactions between organisms and drugs and their mechanisms. Pharmacology plays a translational role in modern medicine, bridging basic research and the clinic. With its economy booming, China has invested an enormous amount of financial and human resources in pharmacological research in the recent decade. As a result, major breakthroughs have been achieved in both basic and clinical research, with the discovery of many potential drug targets and biomarkers that has made a sizable contribution to the overall advancement of pharmacological sciences. In this article, we review recent research efforts and representative scientific achievements and discuss future challenges and directions for the pharmacological sciences in China.


Subject(s)
Pharmacology , Animals , China , Drug Discovery , Humans , Research
4.
Mol Neurobiol ; 54(3): 1967-1977, 2017 04.
Article in English | MEDLINE | ID: mdl-26910813

ABSTRACT

Alzheimer's disease (AD) is the most common dementia and the trigger of its pathological cascade is widely believed to be the overproduction and accumulation of ß-amyloid protein (Aß) in the affected brain. However, effective AD remedies are still anxiously awaited. Recent evidence suggests that curcumin may be a potential agent for AD treatment. In this study, we used 5×FAD transgenic mice as an AD model to investigate the effects of curcumin on AD. Our results showed that curcumin administration (150 or 300 mg/kg/day, intragastrically, for 60 days) dramatically reduced Aß production by downregulating BACE1 expression, preventing synaptic degradation, and improving spatial learning and memory impairment of 5×FAD mice. These findings suggest that curcumin is a potential candidate for AD treatment.


Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Aspartic Acid Endopeptidases/antagonists & inhibitors , Aspartic Acid Endopeptidases/biosynthesis , Curcumin/therapeutic use , Memory Disorders/metabolism , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Amyloid Precursor Protein Secretases/genetics , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Aspartic Acid Endopeptidases/genetics , Curcumin/pharmacology , Gene Expression , Male , Memory Disorders/drug therapy , Memory Disorders/pathology , Mice , Mice, Inbred C57BL , Mice, Transgenic
5.
Chin Med J (Engl) ; 129(23): 2845-2852, 2016 12 05.
Article in English | MEDLINE | ID: mdl-27901000

ABSTRACT

BACKGROUND: Amyloid ß (Aß) deposits and the endoplasmic reticulum stress (ERS) are both well established in the development and progression of Alzheimer's disease (AD). However, the mechanism and role of Aß-induced ERS in AD-associated pathological progression remain to be elucidated. METHODS: The five familial AD (5×FAD) mice and wild-type (WT) mice aged 2, 7, and 12 months were used in the present study. Morris water maze test was used to evaluate their cognitive performance. Immunofluorescence and Western blot analyses were used to examine the dynamic changes of pro-apoptotic (CCAAT/enhancer-binding protein homologous protein [CHOP] and cleaved caspase-12) and anti-apoptotic factors (chaperone glucose-regulated protein [GRP] 78 and endoplasmic reticulum-associated protein degradation-associated ubiquitin ligase synovial apoptosis inhibitor 1 [SYVN1]) in the ERS-associated unfolded protein response (UPR) pathway. RESULTS: Compared with age-matched WT mice, 5×FAD mice showed higher cleaved caspase-3, lower neuron-positive staining at the age of 12 months, but earlier cognitive deficit at the age of 7 months (all P < 0.05). Interestingly, for 2-month-old 5×FAD mice, the related proteins involved in the ERS-associated UPR pathway, including CHOP, cleaved caspase-12, GRP 78, and SYVN1, were significantly increased when compared with those in age-matched WT mice (all P < 0.05). Moreover, ERS occurred mainly in neurons, not in astrocytes. CONCLUSIONS: These findings suggest that compared with those of age-matched WT mice, ERS-associated pro-apoptotic and anti-apoptotic proteins are upregulated in 2-month-old 5×FAD mice, consistent with intracellular Aß aggregation in neurons.


Subject(s)
Alzheimer Disease/metabolism , Endoplasmic Reticulum Stress/physiology , Neurons/metabolism , Amyloid beta-Peptides/metabolism , Animals , Apoptosis/physiology , Blotting, Western , Caspase 12/metabolism , Endoplasmic Reticulum Chaperone BiP , Frontal Lobe/metabolism , Heat-Shock Proteins/metabolism , Immunohistochemistry , Mice , Mice, Transgenic , Transcription Factor CHOP/metabolism , Ubiquitin-Protein Ligases/metabolism , Unfolded Protein Response/physiology
6.
Mol Neurodegener ; 11(1): 51, 2016 07 12.
Article in English | MEDLINE | ID: mdl-27406263

ABSTRACT

BACKGROUND: Apolipoprotein E (ApoE) is a major lipid carrier that supports lipid transport and injury repair in the brain. The APOE ε4 allele is associated with depression, mild cognitive impairment (MCI) and dementia; however, the precise molecular mechanism through which ApoE4 influences the risk of disease development remains unknown. To address this gap in knowledge, we investigated the potential effects of chronic unpredictable mild stress (CUMS) on ApoE3 and ApoE4 target replacement (ApoE3-TR and ApoE4-TR) mice. RESULTS: All ApoE-TR mice exposed to CUMS at 3 months old recovered from a depression-like state by the age of 12 months. Of note, ApoE4-TR mice, unlike age-matched ApoE3-TR mice, displayed impaired spatial cognitive abilities, loss of GABAergic neurons, decreased expression of Reelin, PSD95, SYN and Fyn, and reduced phosphorylation of NMDAR2B and CREB. CONCLUSION: These results suggest that early-life stress may mediate cognitive impairment in middle-age ApoE4-TR mice through sustained reduction of GABAergic neurons and Reelin expression, which might further diminish the activation of the Fyn/NMDAR2B signaling pathway.


Subject(s)
Apolipoprotein E4/genetics , Dementia/metabolism , Memory/physiology , Neurons/metabolism , Spatial Learning/physiology , Stress, Psychological/physiopathology , Aging , Animals , Apolipoprotein E4/metabolism , Humans , Male , Mice , Mice, Transgenic , Reelin Protein
7.
Chin Med J (Engl) ; 129(15): 1835-44, 2016 Aug 05.
Article in English | MEDLINE | ID: mdl-27453234

ABSTRACT

BACKGROUND: Amyloid ß (Aß) has been established as a key factor for the pathological changes in the brains of patients with Alzheimer's disease (AD), and cellular senescence is closely associated with aging and cognitive impairment. However, it remains blurred whether, in the AD brains, Aß accelerates the neuronal senescence and whether this senescence, in turn, impairs the cognitive function. This study aimed to explore the expression of senescence-associated genes in the hippocampal tissue from young to aged 5XFAD mice and their age-matched wild type (WT) mice to determine whether senescent neurons are present in the transgenic AD mouse model. METHODS: The 5XFAD mice and age-matched wild type mice, both raised from 1 to 18 months, were enrolled in the study. The senescence-associated genes in the hippocampus were analyzed and differentially expressed genes (DEGs) were screened by quantitative real-time polymerase chain reaction. Cognitive performance of the mice was evaluated by Y-maze and Morris water maze tests. Oligomeric Aß (oAß) (1-42) was applied to culture primary neurons to simulate the in vivo manifestation. Aging-related proteins were detected by Western blotting analysis and immunofluorescence. RESULTS: In 5XFAD mice, of all the DEGs, the senescence-associated marker p16 was most significantly increased, even at the early age. It was mainly localized in neurons, with a marginal expression in astrocytes (labeled as glutamine synthetase), nil expression in activated microglia (labeled as Iba1), and negatively correlated with the spatial cognitive impairments of 5XFAD mice. oAß (1-42) induced the production of senescence-related protein p16, but not p53 in vitro, which was in line with the in vivo manifestation. CONCLUSIONS: oAß-accelerated neuronal senescence may be associated with the cognitive impairment in 5XFAD mice. Senescence-associated marker p16 can serve as an indicator to estimate the cognitive prognosis for AD population.


Subject(s)
Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Cognition Disorders/metabolism , Neurons/metabolism , Alzheimer Disease/physiopathology , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Protein Precursor/metabolism , Animals , Aspartic Acid Endopeptidases/genetics , Aspartic Acid Endopeptidases/metabolism , Brain/metabolism , Brain/physiopathology , Cells, Cultured , Cellular Senescence/genetics , Cellular Senescence/physiology , Cognition/physiology , Cognition Disorders/physiopathology , Disease Models, Animal , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neurons/pathology , Real-Time Polymerase Chain Reaction
9.
Curr Alzheimer Res ; 13(9): 1048-55, 2016.
Article in English | MEDLINE | ID: mdl-27087442

ABSTRACT

APOE4 is the greatest genetic risk factor for Alzheimer's disease (AD), particularly associated with increased levels of amyloid-ß (Aß) and amyloid deposition. However, it remains unclear whether APOE4 is associated with greater tau phosphorylation and neurofibrillary tangle formation, a hallmark of AD leading to structural disruption of the neuronal cytoskeleton. The current study used 3 and 7 month old EFAD mice, which express human APOE and over-express specifically human Aß42 via 5 familial-AD (FAD) mutations, to investigate APOE genotype-specific effects on site-specific tau phosphorylation. The results reveal that AD-like site-specific tau phosphorylation was increased in E4FAD mice, accompanied by disrupted cortical neuronal morphology, compared to E3FAD mice. Further analysis demonstrated that the levels of CDK5, its regulatory subunits (p35 and p25) and calpain (including calpain1 and calpain2), but not GSK3ß, were significantly increased in E4FAD mice compared to E3FAD mice. These results suggest that the APOE4 genotype contributes to increased site-specific tau phosphorylation via activation of the calpain-CDK5 signaling pathway.


Subject(s)
Amyloid beta-Peptides/metabolism , Apolipoprotein E4/metabolism , Calpain/metabolism , Cyclin-Dependent Kinase 5/metabolism , Peptide Fragments/metabolism , tau Proteins/metabolism , Aging/metabolism , Aging/pathology , Animals , Apolipoprotein E4/genetics , Cerebral Cortex/metabolism , Cerebral Cortex/pathology , Glycogen Synthase Kinase 3 beta/metabolism , Humans , Male , Mice, Transgenic , Mutation , Neurons/metabolism , Neurons/pathology , Phosphorylation/physiology , Signal Transduction/physiology
10.
Mol Neurobiol ; 53(9): 6397-6406, 2016 11.
Article in English | MEDLINE | ID: mdl-26582466

ABSTRACT

Due to its apparent rate-limiting function, BACE1 (ß-secretase) appears to be a prime target for prevention of amyloid-ß (Aß) generation in brains with Alzheimer's disease (AD). The activity of BACE1 is regulated by peroxisome proliferator-activated receptor-γ (PPARγ), a transcription factor binding site of the BACE1 promoter, indicating that PPARγ may be a potential target for AD treatment. Several studies have demonstrated that PPARγ activation is involved in the immunostimulation of amyloid-ß precursor protein processing by nonsteroidal anti-inflammatory drugs (NSAIDs). The present study found that tripchlorolide (T4), with a similar chemical structure to that of NSAIDs, decreased the levels of Aß secreted in N2a-APP695 cells. T4 treatment reduced the mRNA and protein levels of BACE1 and the protein level of sAPPß, a cleaved N-terminal fragment of APP by BACE1. The treatment also translocated PPARγ from cytoplasm to nuclear. Intriguingly, T4, like pioglitazone (a PPARγ agonist), suppressed the BACE1 activity in N2a-APP695 cells, which was attenuated by GW9662 (a PPARγ antagonist). These results indicate that T4 may be a PPARγ agonist to enhance the binding of nuclear PPARγ to the BACE1 promoter, which may in turn inhibit the transcription and translation of BACE1, suppress the activity of BACE1, and ultimately attenuate the generation of Aß. Due to its capability to alter Aß generation and to protect central neural system against the neurotoxicity of Aß, T4 may serve as a promising agent in modulating Aß-related pathology in Alzheimer's disease.


Subject(s)
Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/metabolism , Aspartic Acid Endopeptidases/metabolism , Diterpenes/pharmacology , PPAR gamma/metabolism , Phenanthrenes/pharmacology , Amyloid Precursor Protein Secretases/genetics , Animals , Aspartic Acid Endopeptidases/genetics , Cell Line, Tumor , Cell Survival/drug effects , Diterpenes/chemistry , Humans , Mice , Mice, Transgenic , Phenanthrenes/chemistry , Protein Biosynthesis/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Transcription, Genetic/drug effects
11.
Chin Med J (Engl) ; 128(16): 2220-7, 2015 Aug 20.
Article in English | MEDLINE | ID: mdl-26265617

ABSTRACT

BACKGROUND: Early diagnosis assumes a vital role in an effective treatment of Alzheimer's disease (AD). Most of the current studies can only make an AD diagnosis after the manifestation of typical clinical symptoms. The present study aimed to investigate typical and other biomarkers of AD to find a possible early biomarker. METHODS: A total of 14 5XFAD mice (at 3 and 6 months old), with 14 age-matched wild-type (WT) mice as control, were enrolled in this case-control study. Morris water maze test was performed to evaluate the cognitive function; buried food pellet test and olfactory maze test were employed to investigate the olfactory function; immunofluorescence to detect amyloid deposition and positron emission tomography to examine 2-deoxy-2-(18F) fluoro-D-glucose ([18F]-FDG) uptake in the hippocampus and cerebral cortex. RESULTS: With the increasing age, cognitive performance (P = 0.0262) and olfactory function were significantly deteriorated (day 1 P = 0.0012, day 2 P = 0.0031, day 3 P = 0.0160, respectively) and the (18F)-FDG uptake was markedly decreased in multi-cerebral regions including the olfactory bulb (P < 0.0001), hippocampus (P = 0.0121), and cerebral cortex (P < 0.0001). Of note, in 3-month-old 5XFAD mice, a significant decline of (18F)-FDG uptake in the olfactory bulb was found when compared with that of age-matched WT mice (P = 0.023) while no significant difference was present when the uptakes in other cerebral regions were compared. CONCLUSIONS: The decline of (18F)-FDG uptake in the olfactory bulb occurs earlier than other incidents, serving as an earlier in vivo biological marker of AD in 5XFAD mice and making early diagnosis of AD possibly.


Subject(s)
Alzheimer Disease/diagnosis , Biomarkers/analysis , Glucose/metabolism , Olfactory Bulb/metabolism , Amyloid/analysis , Animals , Animals, Genetically Modified , Fluorodeoxyglucose F18/metabolism , Mice , Positron-Emission Tomography
12.
Glia ; 63(12): 2208-19, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26200696

ABSTRACT

Oxidative stress plays an important role in the progression of Alzheimer's disease (AD) and other neurodegenerative conditions. Glutathione (GSH), the major antioxidant in the central nervous system, is primarily synthesized and released by astrocytes. We determined if ß-amyloid (Aß42), crucially involved in Alzheimer's disease, affected GSH release. Monomeric Aß (mAß) stimulated GSH release from cultured cortical astrocytes more effectively than oligomeric Aß (oAß) or fibrillary Aß (fAß). Monomeric Aß increased the expression of the transporter ABCC1 (also referred to as MRP1) that is the main pathway for GSH release. GSH release from astrocytes, with or without mAß stimulation, was reduced by pharmacological inhibition of ABCC1. Astrocytes robustly express connexin proteins, especially connexin43 (Cx43), and mAß also stimulated Cx43 hemichannel-mediated glutamate and GSH release. Aß-stimulation facilitated hemichannel opening in the presence of normal extracellular calcium by reducing astrocyte cholesterol level. Aß treatment did not alter the intracellular concentration of reduced or oxidized glutathione. Using a mouse model of AD with early onset Aß deposition (5xFAD), we found that cortical ABCC1 was significantly increased in temporal register with the surge of Aß levels in these mice. ABCC1 levels remained elevated from 1.5 to 3.5 months of age in 5xFAD mice, before plunging to subcontrol levels when amyloid plaques appeared. Similarly, in cultured astrocytes, prolonged incubation with aggregated Aß, but not mAß, reduced induction of ABCC1 expression. These results support the hypothesis that in the early stage of AD pathogenesis, less aggregated Aß increases GSH release from astrocytes (via ABCC1 transporters and Cx43 hemichannels) providing temporary protection from oxidative stress which promotes AD development.


Subject(s)
Amyloid beta-Peptides/metabolism , Astrocytes/metabolism , Glutathione/metabolism , Aging/metabolism , Alzheimer Disease/metabolism , Animals , Astrocytes/drug effects , Calcium/metabolism , Cells, Cultured , Cerebral Cortex/metabolism , Cholesterol/metabolism , Connexin 43/genetics , Connexin 43/metabolism , Disease Models, Animal , Mice, Inbred C57BL , Mice, Transgenic , Multidrug Resistance-Associated Proteins/antagonists & inhibitors , Multidrug Resistance-Associated Proteins/metabolism , Oxidation-Reduction , Plaque, Amyloid/metabolism
13.
Mol Neurodegener ; 10: 7, 2015 Mar 05.
Article in English | MEDLINE | ID: mdl-25871877

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) causes progressive loss of memory and cognition, exacerbated by APOE4, the greatest genetic risk factor for AD. One proposed mechanism for apolipoprotein E (apoE) effects on cognition is via NMDAR-dependent signaling. APOE genotype-specific effects on this pathway were dissected using EFAD-transgenic (Tg) mice (5xFAD mice, that over-express human amyloid-beta (Aß) via 5 familial-AD (FAD) mutations, and express human apoE), and 5xFAD/APOE-knockout (KO) mice. Previous data from EFAD-Tg mice demonstrate age-dependent (2-6 months), apoE-specific effects on the development of Aß pathology. This study tests the hypothesis that apoE4 impairs cognition via modulation of NMDAR-dependent signaling, specifically via a loss of function by comparison of E4FAD mice with 5xFAD/APOE-KO mice, E3FAD and E2FAD mice. RESULTS: Using female E2FAD, E3FAD, E4FAD and 5xFAD/APOE-KO mice aged 2-, 4-, and 6-months, the Y-maze and Morris water maze behavioral tests were combined with synaptic protein levels as markers of synaptic viability. The results demonstrate a greater age-induced deficit in cognition and reduction in PSD95, drebrin and NMDAR subunits in the E4FAD and 5xFAD/APOE-KO mice compared with E2FAD and E3FAD mice, consistent with an apoE4 loss of function. Interestingly, for NMDAR-mediated signaling, the levels of p-CaMK-II followed this same apoE-specific pattern as cognition, while the levels of p-CREB and BDNF demonstrate an apoE4 toxic gain of function: E2FAD > E3FAD > 5xFAD/APOE-KO > E4FAD. CONCLUSION: These findings suggest that compared with E2FAD and E3FAD, E4FAD and 5xFAD/APOE-KO mice exhibit enhanced age-induced reductions in cognition and key synaptic proteins via down-regulation of an NMDAR signaling pathway, consistent with an apoE4 loss of function. However, levels of p-CREB and BDNF, signaling factors common to multiple pathways, suggest a gain of toxic function. Publications in this field present contradictory results as to whether APOE4 imparts a loss or gain of function. As with the results reported herein, the overall effect of APOE4 on a given CNS-specific measure will be the product of multiple overlapping mechanisms. Thus, caution remains critical in determining whether APOE gene inactivation or therapies that correct the loss of positive function related to apoE4, are the appropriate therapeutic response.


Subject(s)
Apolipoprotein E4/genetics , Apolipoprotein E4/metabolism , Cognition/physiology , Receptors, N-Methyl-D-Aspartate/metabolism , Signal Transduction/genetics , Aging , Alzheimer Disease/metabolism , Amyloid beta-Peptides/genetics , Amyloid beta-Peptides/metabolism , Animals , Down-Regulation , Memory/physiology , Mice, Knockout , Mutation/genetics , Signal Transduction/physiology
14.
J Neurochem ; 133(1): 38-52, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25661995

ABSTRACT

Alzheimer's disease (AD) is characterized by early impairments in memory and progressive neurodegeneration. Disruption of synaptic plasticity processes that underlie learning and memory contribute partly to this pathophysiology. Tripchlorolide (T4 ), an extract from a traditional Chinese herbal Tripterygium wilfordii Hook F, has been shown to be neuroprotective in animal models of Parkinson's disease and to improve cognitive deficits in senescence-accelerated mouse P8. In this study, we investigated the effect of T4 on cognitive decline and synaptic plasticity in five times familial AD (5XFAD) mice co-expressing mutated amyloid precursor protein and presenilin-1. Five-month-old 5XFAD mice and wild type littermates were intraperitoneally injected with T4 , 5 µg/kg or 25 µg/kg, every other day for 60 days. T4 treatment significantly improved spatial learning and memory, alleviated synaptic ultrastructure degradation, up-regulated expression of synapse-related proteins, including synaptophysin, post-synaptic density-95, N-methyl-D-aspartate receptor subunit 1, phosphorylation of calcium/calmodulin dependent protein kinase II α, and phosphorylation of cyclic AMP-response element binding protein, and promoted activation of the phophoinositide-3-kinase-Akt-mammalian target of rapamycin signaling pathway in 5XFAD mice. Accumulation of amyloid ß (Aß) may contribute to synapse dysfunction and memory impairment in AD. We found that T4 treatment significantly reduced cerebral Aß deposits and lowered Aß levels in brain homogenates. These effects coincided with a reduction in cleavage of ß-carboxyl-terminal amyloid precursor protein (APP) fragment, levels of soluble APPß, and protein expression of ß-site APP cleaving enzyme 1. Taken together, our findings identify T4 as a potent negative regulator of brain Aß levels and show that it significantly ameliorates synaptic degeneration and cognitive deficits in a mouse model of AD.


Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/psychology , Amyloid beta-Peptides/metabolism , Cognition/drug effects , Diterpenes/therapeutic use , Immunosuppressive Agents/therapeutic use , Phenanthrenes/therapeutic use , Synapses/metabolism , Alzheimer Disease/metabolism , Amyloid beta-Peptides/genetics , Animals , Humans , Maze Learning/drug effects , Mice , Mice, Transgenic , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Psychomotor Performance/drug effects , Synapses/drug effects , Synapses/ultrastructure , TOR Serine-Threonine Kinases/metabolism
15.
Neurobiol Aging ; 35(3): 655-68, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24112790

ABSTRACT

Kisspeptin neurons in the rostral periventricular area of the third ventricle (RP3V) play a key role in relaying the positive feedback effects of estradiol that activate gonadotropin-releasing hormone (GnRH) neurons and drive a surge in the GnRH/luteinizing hormone (LH) level. However, the precise role of kisspeptin neurons during female reproductive senescence remains unclear. Focusing on middle-aged intact female mice with irregular estrous cycles, we found a parallel decline in c-Fos-positive kisspeptin neurons and c-Fos-positive GnRH neurons at the time of the GnRH/LH surge. Furthermore, in kisspeptin neurons, the expression of estrogen receptor α (ERα), but not progesterone receptor (PR), decreased with age. Interestingly, some kisspeptin neurons in the RP3V, but none of the GnRH neurons in the rostral preoptic area (rPOA), had a characteristic cellular senescence in middle-aged mice and old mice. These data suggest that, among the groups of neurons involved in reproductive control, the kisspeptin neurons in the RP3V are likely among the earliest to undergo aging processes and thus participate in initiating the early reproductive decline.


Subject(s)
Aging/genetics , Aging/pathology , Brain/cytology , Brain/pathology , Gonadotropin-Releasing Hormone/physiology , Kisspeptins/physiology , Neurons/pathology , Reproduction/genetics , Reproduction/physiology , Animals , Brain/metabolism , Estrogen Receptor alpha , Female , Gonadotropin-Releasing Hormone/metabolism , Immunohistochemistry , Kisspeptins/metabolism , Mice , Mice, Inbred C57BL , Neurons/metabolism , Neurons/physiology , Proto-Oncogene Proteins c-fos , Receptors, Progesterone
16.
Behav Brain Res ; 258: 8-18, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24140565

ABSTRACT

Deficits in cognition and performance accompanying age-related neurodegenerative diseases such as Alzheimer's disease (AD) are closely associated with the impairment of synaptic plasticity. Here, using a mouse model of senescence-accelerated P8 (SAMP8), we reported the role of tripchlorolide (T4), an extract of the natural herb Tripterygium wilfordii Hook F, in improving cognitive deficits and promoting the long-term potentiation (LTP) of hippocampal slices via the N-methyl-D-aspartate receptor (NMDAR)-dependent signaling pathway. Our results demonstrated that chronic administration of T4 at low doses (0.25, 1.0, or 4.0 µg/kg per day, injected intraperitoneally for 75 days) significantly improved learning and memory function in aged SAMP8 mice, as indicated by a chain of behavioral tests including the Y-maze and Morris water maze. Additionally, T4 reversed the impaired LTP in hippocampal CA1 regions of SAMP8 mice in a dose-dependent manner. Moreover, it upregulated the levels of phospho-NMDAR1, postsynaptic density-95 (PSD-95), phospho-calcium-calmodulin dependent kinase II (CaMKII), phospho-CREB and brain derived neurotrophic factor (BDNF) in the hippocampus. This indicates that T4 prevents the impairment of NMDAR-mediated synaptic plasticity-related signal molecules. At optimal doses, T4 did not show significant side-effects on blood counts, blood biochemical measures, or survival of the mice. This novel mechanism in reversing age-related synaptic dysfunction and NMDAR functional deficits suggests that T4 can halt the manifestation of a key early-stage event in AD. With the consideration of SAMP8 mice as a model to develop therapeutic interventions for AD, our findings provide new insight into the clinical application of tripchlorolide in AD treatment.


Subject(s)
Cognition Disorders/drug therapy , Cognition/drug effects , Diterpenes/pharmacology , Hippocampus/drug effects , Neuronal Plasticity/drug effects , Phenanthrenes/pharmacology , Receptors, N-Methyl-D-Aspartate/metabolism , Synapses/drug effects , Aging/drug effects , Aging/metabolism , Animals , Cognition Disorders/metabolism , Cognition Disorders/physiopathology , Diterpenes/therapeutic use , Hippocampus/physiopathology , Male , Maze Learning/drug effects , Mice , Neuronal Plasticity/physiology , Phenanthrenes/therapeutic use , Synapses/physiology
17.
Article in Chinese | MEDLINE | ID: mdl-23662411

ABSTRACT

OBJECTIVE: To observe time points of the expressions of basic fibroblast growth factor (bFGF), growth associated protein-43 (GAP-43) and neurogenesis after cerebral ischemia/reperfusion in rats and explore its possible mechanism of neurogenesis. METHODS: Models of middle cerebral artery occlusion (MCAO) were established in SD rats which were divided into 3 d, 7 d, 14 d and 28 d groups (n = 6). The neurological severity was evaluated by neurological severity scores (NSS) and scores of motor test (SMT). Neuronal injury in the boundary zone of the infarction area was evaluated by TUNEL and Nissl staining; The expressions of bFGF and GAP-43 and neurogenesis were evaluated by Western blot and 5-bromodeoxyuridine (Brdu) fluorescence staining, respectively. RESULTS: It showed up neurologic impairment and motor dysfunction after cerebral ischemia/reperfusion in rats at 3 d, the numbers of neuron apoptosis also peaked at 3d, the protein levels of bFGF and GAP-43 were significantly increased in time-dependent manner, peaked at 7 d and then decreased gradually, meanwhile, Brdu and NeuN double fluorescence staining displayed scattered Brdu-and NeuN-positive cells in the boundary zone of the infarction area. CONCLUSION: These results suggest that the upregulation of bFGF and GAP-43 may contribute to the neurogenesis after cerebral ischemia/reperfusion.


Subject(s)
Brain Ischemia , Fibroblast Growth Factor 2/metabolism , GAP-43 Protein/metabolism , Neurogenesis , Reperfusion Injury , Animals , Brain Ischemia/metabolism , Brain Ischemia/physiopathology , Male , Rats , Rats, Sprague-Dawley , Reperfusion Injury/metabolism , Reperfusion Injury/physiopathology
18.
Mar Drugs ; 11(4): 1019-34, 2013 Mar 28.
Article in English | MEDLINE | ID: mdl-23538867

ABSTRACT

OBJECTIVE: To investigate astaxanthin (ATX) neuroprotection, and its mechanism, on a 1-methyl-4-phenyl-pyridine ion (MPP+)-induced cell model of Parkinson's disease. METHODS: Mature, differentiated PC12 cells treated with MPP+ were used as an in vitro cell model. The MTT assay was used to investigate cell viability after ATX treatment, and western blot analysis was used to observe Sp1 (activated transcription factor 1) and NR1 (NMDA receptor subunit 1) protein expression, real-time PCR was used to monitor Sp1 and NR1 mRNA, and cell immunofluorescence was used to determine the location of Sp1 and NR1 protein and the nuclear translocation of Sp1. RESULTS: PC12 cell viability was significantly reduced by MPP+ treatment. The expression of Sp1 and NR1 mRNA and protein were increased compared with the control (p < 0.01). Following co-treatment with ATX and MPP+, cell viability was significantly increased, and Sp1 and NR1 mRNA and protein were decreased, compared with the MPP+ groups (p < 0.01). In addition, mithracycin A protected PC12 cells from oxidative stress caused by MPP+ by specifically inhibiting the expression of Sp1. Moreover, cell immunofluorescence revealed that ATX could suppress Sp1 nuclear transfer. CONCLUSION: ATX inhibited oxidative stress induced by MPP+ in PC12 cells, via the SP1/NR1 signaling pathway.


Subject(s)
Neuroprotective Agents/pharmacology , Oxidative Stress/drug effects , Parkinson Disease/drug therapy , 1-Methyl-4-phenylpyridinium/toxicity , Animals , Blotting, Western , Fluorescent Antibody Technique , PC12 Cells , Parkinson Disease/physiopathology , Plicamycin/analogs & derivatives , Plicamycin/pharmacology , RNA, Messenger/metabolism , Rats , Real-Time Polymerase Chain Reaction , Receptors, N-Methyl-D-Aspartate/genetics , Receptors, N-Methyl-D-Aspartate/metabolism , Signal Transduction/drug effects , Sp1 Transcription Factor/genetics , Sp1 Transcription Factor/metabolism , Xanthophylls/pharmacology
19.
Neurosci Bull ; 29(1): 121-4, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23361522

ABSTRACT

During recent years, major advances have been made in neuroscience, i.e., asynchronous release, three-dimensional structural data sets, saliency maps, magnesium in brain research, and new functional roles of long non-coding RNAs. Especially, the development of optogenetic technology provides access to important information about relevant neural circuits by allowing the activation of specific neurons in awake mammals and directly observing the resulting behavior. The Grand Research Plan for Neural Circuits of Emotion and Memory was launched by the National Natural Science Foundation of China. It takes emotion and memory as its main objects, making the best use of cutting-edge technologies from medical science, life science and information science. In this paper, we outline the current status of neural circuit studies in China and the technologies and methodologies being applied, as well as studies related to the impairments of emotion and memory. In this phase, we are making efforts to repair the current deficiencies by making adjustments, mainly involving four aspects of core scientific issues to investigate these circuits at multiple levels. Five research directions have been taken to solve important scientific problems while the Grand Research Plan is implemented. Future research into this area will be multimodal, incorporating a range of methods and sciences into each project. Addressing these issues will ensure a bright future, major discoveries, and a higher level of treatment for all affected by debilitating brain illnesses.


Subject(s)
Brain/physiology , Emotions/physiology , Memory/physiology , Neural Pathways/physiology , Neurosciences/methods , China , Humans
20.
BMC Complement Altern Med ; 12: 82, 2012 Jun 28.
Article in English | MEDLINE | ID: mdl-22742579

ABSTRACT

BACKGROUND: Parkinson's disease is a high incidence neurodegenerative disease in elderly people, and oxidative stress plays an important role in the pathogenesis. Oxygen metabolism in the brain is high, which lacks an antioxidative protection mechanism. Recently, it has been found that polyphenols play an important role in antioxidation. (-)-epigallocatechin-3-gallate (EGCG) is an important component of tea polyphenols and its biological effects, such as strong antioxidation, scavenging of free radicals and anti-apoptosis, can pass through the blood brain barrier. The SIRT1/PGC-1α signaling pathway has not been reported in PC12 cells. Therefore, research of the protective mechanism of EGCG in PC12 cells damaged by -methyl-4-phenyl-pyridine (MMP+) may provide a new insight into protect against and treatment of Parkinson's disease. METHODS: MPP(+)-treated highly differentiated PC12 cells were used as the in vitro cell model. An MTT assay was used to investigate cell viability after EGCG treatment, a dichlorofluorescin diacetate assay was used to measure reactive oxygen species (ROS) production, western blot analysis was used to observe PGC-1α and SIRT1 protein expression, and real-time PCR to observe PGC-1α, SOD1 and GPX1 mRNA expression. RESULTS: PC12 cell viability was significantly reduced after MPP(+) treatment by 11.46% compared with that of the control (P < 0.05). However, cell viability was unchanged by 10 µmol/L EGCG treatment. In co-treatments with EGCG and MPP(+), cell viability was significantly increased by 12.92% (P < 0.05) and MPP(+)-induced ROS production was markedly decreased. PGC-1α mRNA expression was obviously upregulated by 21.51% (P < 0.05), and SOD1 and GPX1 mRNA expression was slightly increased by 12.94% and 15.63% (P > 0.05), respectively, by treatment with EGCG and then MPP(+) for 12 h. The mRNA expression of PGC-1α, SOD1 and GPX1 was increased by 25.17%, 40% and 146% (all P < 0.05), respectively, by treatment with EGCG and then MPP(+) for 24 h. Such effects were not observed with MPP(+) treatment alone. CONCLUSION: The SIRT1/PGC-1α pathway is one of the mechanisms of EGCG suppression of MPP(+)-induced injury of PC12 cells.


Subject(s)
Antioxidants/pharmacology , Camellia sinensis/chemistry , Catechin/analogs & derivatives , Cell Survival/drug effects , Oxidative Stress/drug effects , Parkinson Disease/metabolism , Phytotherapy , 1-Methyl-4-phenylpyridinium , Animals , Antioxidants/metabolism , Antioxidants/therapeutic use , Catechin/pharmacology , Catechin/therapeutic use , Glutathione Peroxidase/metabolism , PC12 Cells , Parkinson Disease/drug therapy , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , RNA, Messenger/metabolism , RNA-Binding Proteins/metabolism , Rats , Reactive Oxygen Species/metabolism , Signal Transduction , Sirtuin 1/metabolism , Superoxide Dismutase/metabolism , Superoxide Dismutase-1 , Tea/chemistry , Transcription Factors/metabolism , Up-Regulation , Glutathione Peroxidase GPX1
SELECTION OF CITATIONS
SEARCH DETAIL
...