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1.
J Biol Chem ; 299(7): 104846, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37211092

RESUMO

Apolipoprotein E (apoE) interaction with amyloid ß-protein precursor (APP) has garnered attention as the therapeutic target for Alzheimer's disease (AD). Having discovered the apoE antagonist (6KApoEp) that blocks apoE binding to N-terminal APP, we tested the therapeutic potential of 6KApoEp on AD-relevant phenotypes in amyloid ß-protein precursor/presenilin 1 (APP/PS1) mice that express each human apoE isoform of apoE2, apoE3, or apoE4 (designated APP/PS1/E2, APP/PS1/E3, or APP/PS1/E4 mice). At 12 months of age, we intraperitoneally administered 6KApoEp (250 µg/kg) or vehicle once daily for 3 months. At 15 months of age, blockage of apoE and N-terminal APP interaction by 6KApoEp treatment improved cognitive impairment in most tests of learning and memory, including novel object recognition and maze tasks in APP/PS1/E2, APP/PS1/E3, and APP/PS1/E4 mice versus each vehicle-treated mouse line and did not alter behavior in nontransgenic littermates. Moreover, 6KApoEp therapy ameliorated brain parenchymal and cerebral vascular ß-amyloid deposits and decreased abundance of amyloid ß-protein (Aß) in APP/PS1/E2, APP/PS1/E3, and APP/PS1/E4 mice versus each vehicle-treated mouse group. Notably, the highest effect in Aß-lowering by 6KApoEp treatment was observed in APP/PS1/E4 mice versus APP/PS1/E2 or APP/PS1/E3 mice. These effects occured through shifting toward lessened amyloidogenic APP processing due to decreasing APP abundance at the plasma membrane, reducing APP transcription, and inhibiting p44/42 mitogen-activated protein kinase phosphorylation. Our findings provide the preclinical evidence that 6KApoEp therapy aimed at targeting apoE and N-terminal APP interaction is a promising strategy and may be suitable for patients with AD carrying the apoE4 isoform.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Animais , Humanos , Camundongos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Apolipoproteínas E/antagonistas & inibidores , Apolipoproteínas E/genética , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Camundongos Transgênicos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
2.
Life (Basel) ; 12(9)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36143476

RESUMO

Alzheimer's disease (AD) is a heterogeneous neurodegenerative disorder and is the most common cause of dementia. Furthermore, aging is considered the most critical risk factor for AD. However, despite the vast amount of research and resources allocated to the understanding and development of AD treatments, setbacks have been more prominent than successes. Recent studies have shown that there is an intricate connection between the immune and central nervous systems, which can be imbalanced and thereby mediate neuroinflammation and AD. Thus, this review examines this connection and how it can be altered with AD. Recent developments in active and passive immunotherapy for AD are also discussed as well as suggestions for improving these therapies moving forward.

3.
Exp Neurol ; 353: 114050, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35307405

RESUMO

Developmental disabilities are defined as disorders that result in the limitation of function due to impaired development of the nervous system; these disabilities can be present in the form of impairments in learning, language, behavior, or physical abilities. Examples of developmental disorders include attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), cerebral palsy (CP), hearing loss, blindness, intellectual disability, and learning disability. Of these disorders, ASD prevalence was 18.5 per 1000 children (1 in 54) aged 8 in 2016. Current literature suggests that deficient levels of heparan sulfate (HS), an acidic and linear glycosaminoglycan (GAG), is likely causative of ASD. The cascading effect of deficient HS levels can offer compelling evidence for the association of HS with ASD. Deficient levels of HS lead to defective Slit/Robo signaling, which affects axonal guidance and dendritic spine formation. Defective Slit/Robo signaling leads to increased Arp2/3 activity and dendritic spine density, which has been observed in the brains of persons with ASD. Therefore, interventions that target HS and its associated pathways may be viable treatment options for ASD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Autístico , Deficiência Intelectual , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Espectro Autista/complicações , Criança , Heparitina Sulfato , Humanos
5.
J Biol Chem ; 295(48): 16251-16266, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-32913125

RESUMO

Several plant-derived compounds have demonstrated efficacy in pre-clinical Alzheimer's disease (AD) rodent models. Each of these compounds share a gallic acid (GA) moiety, and initial assays on this isolated molecule indicated that it might be responsible for the therapeutic benefits observed. To test this hypothesis in a more physiologically relevant setting, we investigated the effect of GA in the mutant human amyloid ß-protein precursor/presenilin 1 (APP/PS1) transgenic AD mouse model. Beginning at 12 months, we orally administered GA (20 mg/kg) or vehicle once daily for 6 months to APP/PS1 mice that have accelerated Alzheimer-like pathology. At 18 months of age, GA therapy reversed impaired learning and memory as compared with vehicle, and did not alter behavior in nontransgenic littermates. GA-treated APP/PS1 mice had mitigated cerebral amyloidosis, including brain parenchymal and cerebral vascular ß-amyloid deposits, and decreased cerebral amyloid ß-proteins. Beneficial effects co-occurred with reduced amyloidogenic and elevated nonamyloidogenic APP processing. Furthermore, brain inflammation, gliosis, and oxidative stress were alleviated. We show that GA simultaneously elevates α- and reduces ß-secretase activity, inhibits neuroinflammation, and stabilizes brain oxidative stress in a pre-clinical mouse model of AD. We further demonstrate that GA increases abundance of a disintegrin and metalloproteinase domain-containing protein 10 (ADAM10, Adam10) proprotein convertase furin and activates ADAM10, directly inhibits ß-site APP cleaving enzyme 1 (BACE1, Bace1) activity but does not alter Adam10 or Bace1 transcription. Thus, our data reveal novel post-translational mechanisms for GA. We suggest further examination of GA supplementation in humans will shed light on the exciting therapeutic potential of this molecule.


Assuntos
Proteína ADAM10/metabolismo , Doença de Alzheimer , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Ácido Gálico/farmacologia , Proteínas de Membrana/metabolismo , Proteína ADAM10/genética , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/enzimologia , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Ácido Aspártico Endopeptidases/genética , Modelos Animais de Doenças , Furina/genética , Furina/metabolismo , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Presenilina-1/genética , Presenilina-1/metabolismo
6.
Front Aging Neurosci ; 12: 580001, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33505301

RESUMO

Propionate, a short-chain fatty acid, serves important roles in the human body. However, our review of the current literature suggests that under certain conditions, excess levels of propionate may play a role in Alzheimer's disease (AD). The cause of the excessive levels of propionate may be related to the Bacteroidetes phylum, which are the primary producers of propionate in the human gut. Studies have shown that the relative abundance of the Bacteroidetes phylum is significantly increased in older adults. Other studies have shown that levels of the Bacteroidetes phylum are increased in persons with AD. Studies on the diet, medication use, and propionate metabolism offer additional potential causes. There are many different mechanisms by which excess levels of propionate may lead to AD, such as hyperammonemia. These mechanisms offer potential points for intervention.

7.
CNS Neurol Disord Drug Targets ; 18(10): 769-778, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31724518

RESUMO

Lithium as a mood stabilizer has been used as the standard pharmacological treatment for Bipolar Disorder (BD) for more than 60 years. Recent studies have also shown that it has the potential for the treatment of many other neurodegenerative disorders, including Alzheimer's, Parkinson's and Huntington's disease, through its neurotrophic, neuroprotective, antioxidant and anti-inflammatory actions. Therefore, exploring its pharmacokinetic features and designing better lithium preparations are becoming important research topics. We reviewed many studies on the pharmacokinetics, drug design and toxicity of lithium based on recent relevant research from PubMed, Web of Science, Elsevier and Springer databases. Keywords used for searching references were lithium, pharmacology, pharmacokinetics, drug design and toxicity. Lithium is rapidly and completely absorbed from the gastrointestinal tract after oral administration. Its level is initially highest in serum and then is evidently redistributed to various tissue compartments. It is not metabolized and over 95% of lithium is excreted unchanged through the kidney, but different lithium preparations may have different pharmacokinetic features. Lithium has a narrow therapeutic window limited by various adverse effects, but some novel drugs of lithium may overcome these problems. Various formulations of lithium have the potential for treating neurodegenerative brain diseases but further study on their pharmacokinetics will be required in order to determine the optimal formulation, dosage and route of administration.


Assuntos
Desenho de Fármacos , Compostos de Lítio/efeitos adversos , Compostos de Lítio/farmacologia , Compostos de Lítio/farmacocinética , Animais , Humanos
8.
Am J Transl Res ; 11(8): 5076-5085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31497223

RESUMO

Apolipoprotein E (apoE) and apoE-mimetic peptides exert prominent anti-inflammatory effects. We determined the anti-inflammatory effects of novel apoE receptor mimetics, composed of the LDL receptor-binding domain of apoE (aa 133-152, ApoEp) or ApoEp with 6 lysines (6KApoEp) or 6 aspartates added at the N-terminus (6DApoEp). BV2 microglia and human THP-1 monocytes were treated with lipopolysaccharide (LPS) in the absence or presence of ApoEp, 6KApoEp or 6DApoEp, followed by determination of pro-inflammatory tumor necrosis factor α (TNFα) and interleukin-6 (IL-6) release by ELISA. As signaling intermediates of inflammation, Signal Transducer and Activator of Transcription 3 (STAT3), Janus-Activated Kinase2 (JAK2) and p38 and p44/42 MAPK phosphorylation levels were determined by Western blot analysis. In addition, we isolated splenocytes from female htau mice treated with 6KApoEp or 6K for 28 weeks, followed by determination of concanavalinA (conA)-mediated interferon gamma (IFNγ) release. 6KApoEp starting at 2.5 µM significantly reduced LPS-mediated TNFα and IL-6 secretion in BV2 and THP-1 cells in a dose-dependent manner. In BV2 cells, 6KApoEp reduced TNFα secretion more effectively than 6DApoEp and ApoEp, which was blocked by PCSK9 treatment, suggesting a role for LDL receptors. 6KApoEp also inhibited LPS-induced p44/42 MAPK, JAK2 and STAT3 phosphorylation, while enhancing p38 MAPK phosphorylation. In addition, conA induced significantly less IFNγ release in splenocytes derived from htau mice treated with 6KApoEp compared with those treated with 6K. Thus, 6KApoEp most effectively reduces LPS-mediated neuroinflammation by interacting with LDL receptors, thus representing a novel anti-inflammatory agent for treatment of neurodegenerative disease.

9.
Biosci Rep ; 39(8)2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31316002

RESUMO

Ovarian cancer remains the leading cause of death among all gynaecological cancers, illustrating the urgent need to understand the molecular mechanisms involved in this disease. Eukaryotic initiation factor 3c (EIF3c) plays an important role in protein translation and cancer cell growth and proliferation, but its role in human ovarian cancer is unclear. Our results showed that EIF3c silencing significantly up-regulated 217 and down-regulated 340 genes. Ingenuity Pathway Analysis (IPA) indicated that the top differentially expressed genes are involved in 'Classical Pathways', 'Diseases and Functions' and 'Networks', especially those involved in signalling and cellular growth and proliferation. In addition, eIF3c silencing inhibited cellular proliferation, enhanced apoptosis and regulated the expression of apoptosis-associated proteins. In conclusion, these results indicate that by dysregulating translational initiation, eIF3c plays an important role in the proliferation and survival of human ovarian cancer cells. These results should provide experimental directions for further in-depth studies on important human ovarian cancer cell pathways.


Assuntos
Apoptose/genética , Proliferação de Células/genética , Fator de Iniciação 3 em Eucariotos/genética , Neoplasias Ovarianas/genética , Linhagem Celular Tumoral , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Ovarianas/patologia , Transdução de Sinais/genética , Regulação para Cima/genética
10.
Biol Psychiatry ; 86(3): 208-220, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31208706

RESUMO

BACKGROUND: The ɛ4 isoform of apolipoprotein E (apoE4) is a major genetic risk factor for the development of sporadic Alzheimer's disease (AD), and its modification has been an intense focus for treatment of AD during recent years. METHODS: We investigated the binding of apoE, a peptide corresponding to its low-density lipoprotein receptor binding domain (amino acids 133-152; ApoEp), and modified ApoEp to amyloid precursor protein (APP) and their effects on amyloid-ß (Aß) production in cultured cells. Having discovered a peptide (6KApoEp) that blocks the interaction of apoE with N-terminal APP, we investigated the effects of this peptide and ApoEp on AD-like pathology and behavioral impairment in 3XTg-AD and 5XFAD transgenic mice. RESULTS: ApoE and ApoEp, but not truncated apoE lacking the low-density lipoprotein receptor binding domain, physically interacted with N-terminal APP and thereby mediated Aß production. Interestingly, the addition of 6 lysine residues to the N-terminus of ApoEp (6KApoEp) directly inhibited apoE binding to N-terminal APP and markedly limited apoE- and ApoEp-mediated Aß generation, presumably through decreasing APP cellular membrane trafficking and p44/42 mitogen-activated protein kinase phosphorylation. Moreover, while promoting apoE interaction with APP by ApoEp exacerbated Aß and tau brain pathologies in 3XTg-AD mice, disrupting this interaction by 6KApoEp ameliorated cerebral Aß and tau pathologies, neuronal apoptosis, synaptic loss, and hippocampal-dependent learning and memory impairment in 5XFAD mice without altering cholesterol, low-density lipoprotein receptor, and apoE expression levels. CONCLUSIONS: These data suggest that disrupting apoE interaction with N-terminal APP may be a novel disease-modifying therapeutic strategy for AD.


Assuntos
Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/metabolismo , Apolipoproteínas E/antagonistas & inibidores , Apolipoproteínas E/metabolismo , Encéfalo/patologia , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Apolipoproteínas E/genética , Células CHO , Cognição/efeitos dos fármacos , Cricetulus , Modelos Animais de Doenças , Feminino , Humanos , Proteína Associada a Proteínas Relacionadas a Receptor de LDL/metabolismo , Masculino , Memória/efeitos dos fármacos , Camundongos , Camundongos Transgênicos
11.
J Neurosci Res ; 97(9): 1066-1080, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31102295

RESUMO

Alzheimer's disease (AD) is characterized by progressive decline of cognition and associated neuropsychiatric signs including weight loss, anxiety, depression, agitation, and aggression, which is particularly pronounced in the female gender. Previously, we have shown that a novel ionic co-crystal of lithium salicylate proline (LISPRO) is an improved lithium formulation compared to the carbonate or salicylate form of lithium in terms of safety and efficacy in reducing AD pathology in Alzheimer's mice. The current study is designed to compare the prophylactic effects of LISPRO, lithium carbonate (LC), and lithium salicylate (LS) on cognitive and noncognitive impairments in female transgenic APPswe/PS1dE9 AD mice. Female APPswe/PS1dE9 mice at 4 months of age were orally treated with low-dose LISPRO, LS, or LC for 9 months at 2.25 mmol lithium/kg/day followed by determination of body weight, growth of internal organs, and cognitive and noncognitive behavior. No significant differences in body or internal organ weight, anxiety or locomotor activity were found between lithium treated and untreated APPswe/PS1dE9 cohorts. LISPRO, LC, and LS prevented spatial cognitive decline, as determined by Morris water maze and depression as determined by tail suspension test. In addition, LISPRO treatment was superior in preventing associative memory decline determined by contextual fear conditioning and reducing irritability determined by touch escape test in comparison with LC and LS. In conclusion, low-dose LISPRO, LC, and LS treatment prevent spatial cognitive decline and depression-like behavior, while LISPRO prevented hippocampal-dependent associative memory decline and irritability in APPswe/PS1dE9 mice.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Comportamento/efeitos dos fármacos , Carbonato de Lítio/farmacologia , Compostos de Lítio/farmacologia , Memória/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Medo/efeitos dos fármacos , Feminino , Elevação dos Membros Posteriores , Locomoção/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Prolina , Salicilatos , Memória Espacial/efeitos dos fármacos
12.
J Neurosci Res ; 97(2): 128-136, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30378715

RESUMO

Ischemic stroke has become a serious public health problem, which is in need of advanced research on the prevention and treatment. As a newly discovered adipokine, C1q/TNF-related protein 9 (CTRP9) plays a vital role in the pathogenesis of coronary atherosclerosis disease (CAD), including regulating energy metabolism, modulating vasomotion, protecting endothelial cells, inhibiting platelet activation, inhibiting pathological vascular remodeling, stabilizing atherosclerotic plaques, and protecting heart. The present review raised a critical question of whether CTRP9 could also have the capacity of protecting the brain tissue and decreasing the severity of brain lesions in the ischemic stroke since CAD and ischemic stroke are both the major subtypes of atherosclerotic vascular diseases which share a large of common pathogenesis in the vascular lesion particularly. Therefore, we proposed that CTRP9 could be a feasible biomarker and potential therapeutic target in ischemic stroke on the basis of the reviewed research reports.


Assuntos
Adiponectina/fisiologia , Isquemia Encefálica/fisiopatologia , Glicoproteínas/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/fisiologia , Animais , Células Endoteliais/fisiologia , Humanos
13.
Cell Transplant ; 27(4): 666-676, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29871524

RESUMO

Alzheimer's Disease (AD) is the leading cause of dementia in the elderly. In healthy individuals, amyloid precursor protein (APP) is cleaved by α-secretase, generating soluble α-amyloid precursor protein (sAPPα), which contributes neuroprotective functions in the neuronal environment. In contrast, in the neurodegenerative environment of AD patients, amyloid-ß-peptide (Aß) of either 40 or 42 residues are generated by increased activity of ß- and γ-secretase. These proteins amalgamate in specific regions of the brain, which disrupts neuronal functions and leads to cognitive impairment. Human umbilical cord blood cells (HUCBC) have proven useful as potential immunomodulatory therapies in various models of neurodegenerative diseases, including AD. Our most recent work studied the impact of umbilical cord blood serum (CBS) on modulation of sAPPα production. Heat-sensitive CBS significantly promoted sAPPα production, indicating that heat-sensitive factor(s) play(s) a role in this process. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis was used to determine the molecular source of α-secretase in purified CBS and aged blood serum (AgBS) fraction. Of the proteins identified, the subunits of C1 complex (C1q, C1r, and C1s) and alpha-2-macroglobulin showed significantly greater levels in purified α-CBS fraction (α-CBSF) compared with the AgBS fraction (AgBSF). Specifically, C1 markedly increased sAPPα and alpha-carboxyl-terminal fragment (α-CTF) production in a dose-dependent fashion, whereas C1q alone only minimally increased and C3 did not increase sAPPα production in the absence of sera. Furthermore, C1q markedly increased sAPPα and α-CTF, while decreasing Aß, in CHO/APPwt cells cultured in the presence of whole sera. These results confirm our initial assumption that APP α-secretase activity in human blood serum is mediated by complement C1, opening a potential therapeutic modality for the future of AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Complemento C1/metabolismo , Sangue Fetal/enzimologia , Idoso , Envelhecimento/sangue , Peptídeos beta-Amiloides/metabolismo , Animais , Células CHO , Complemento C1/isolamento & purificação , Complemento C3b/metabolismo , Cricetinae , Cricetulus , Temperatura Alta , Humanos , Camundongos , Proteômica
14.
Cell Transplant ; 27(3): 438-455, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29560732

RESUMO

Alzheimer's disease (AD) is an age-related disorder that affects cognition. Our previous studies showed that the neuroprotective fragment of amyloid procurer protein (APP) metabolite, soluble APPα (sAPPα), interferes with ß-site APP-cleaving enzyme 1 (BACE1, ß-secretase) cleavage and reduces amyloid-ß (Aß) generation. In an attempt to identify approaches to restore sAPPα levels, we found that human cord blood serum (CBS) significantly promotes sAPPα production compared with adult blood serum (ABS) and aged blood serum (AgBS) in Chinese hamster ovary cells stably expressing wild-type human APP. Interestingly, CBS selectively mediated the α-secretase cleavage of human neuron-specific recombinant APP695 in a cell-free system independent of tumor necrosis factor-α converting enzyme (TACE; a disintegrin and metalloproteinase domain-containing protein 17 [ADAM17]) and ADAM. Subsequently, using 3-step chromatographic separation techniques (i.e., diethylaminoethanol, size-exclusion, and ion-exchange chromatography), we purified and ultimately identified a CBS-specific fraction with enhanced α-secretase catalytic activity (termed αCBSF) and found that αCBSF has more than 3,000-fold increased α-secretase catalytic activity compared with the original pooled CBS. Furthermore, intracerebroventricular injection of αCBSF markedly increased cerebral sAPPα levels together with significant decreases in cerebral Aß production and abnormal tau (Thr231) phosphorylation compared with the AgBS fraction with enhanced α-secretase activity (AgBSF) treatment in triple transgenic Alzheimer's disease (3xTg-AD) mice. Moreover, AgBSF administered intraperitoneally to transgenic mice with five familial Alzheimer's disease mutations (5XFAD) via an osmotic mini pump for 6 weeks (wk) ameliorated ß-amyloid plaques and reversed cognitive impairment measures. Together, our results propose the necessity for further study aimed at identification and characterization of α-secretase in CBS for novel and effective AD therapy.


Assuntos
Doença de Alzheimer/enzimologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Células CHO , Cricetulus , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Camundongos , Fosforilação , Proteínas tau/metabolismo
15.
Cell Med ; 10: 2155179017722280, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-32634177

RESUMO

In the United States, Alzheimer's disease (AD) is the most common cause of dementia, accompanied by substantial economic and emotional costs. During 2015, more than 15 million family members who provided care to AD patients had an estimated total cost of 221 billion dollars. Recent studies have shown that elevated total plasma levels of homocysteine (tHcy), a condition known as hyperhomocysteinemia (HHcy), is a risk factor for AD. HHcy is associated with cognitive decline, brain atrophy, and dementia; enhances the vulnerability of neurons to oxidative injury; and damages the blood-brain barrier. Many therapeutic supplements containing vitamin B12 and folate have been studied to help decrease tHcy to a certain degree. However, a therapeutic cocktail approach with 5-methyltetrahydrofolate, methyl B12, betaine, and N-acetylcysteine (NAC) have not been studied. This novel approach may help target multiple pathways simultaneously to decrease tHcy and its toxicity substantially.

16.
Cell Death Dis ; 8(6): e2880, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28617434

RESUMO

Lithium has been marketed in the United States of America since the 1970s as a treatment for bipolar disorder. More recently, studies have shown that lithium can improve cognitive decline associated with Alzheimer's disease (AD). However, the current United States Food and Drug Administration-approved lithium pharmaceutics (carbonate and citrate chemical forms) have a narrow therapeutic window and unstable pharmacokinetics that, without careful monitoring, can cause serious adverse effects. Here, we investigated the safety profile, pharmacokinetics, and therapeutic efficacy of LISPRO (ionic co-crystal of lithium salicylate and l-proline), lithium salicylate, and lithium carbonate (Li2CO3). We found that LISPRO (8-week oral treatment) reduces ß-amyloid plaques and phosphorylation of tau by reducing neuroinflammation and inactivating glycogen synthase kinase 3ß in transgenic Tg2576 mice. Specifically, cytokine profiles from the brain, plasma, and splenocytes suggested that 8-week oral treatment with LISPRO downregulates pro-inflammatory cytokines, upregulates anti-inflammatory cytokines, and suppresses renal cyclooxygenase 2 expression in transgenic Tg2576 mice. Pharmacokinetic studies indicated that LISPRO provides significantly higher brain lithium levels and more steady plasma lithium levels in both B6129SF2/J (2-week oral treatment) and transgenic Tg2576 (8-week oral treatment) mice compared with Li2CO3. Oral administration of LISPRO for 28 weeks significantly reduced ß-amyloid plaques and tau-phosphorylation. In addition, LISPRO significantly elevated pre-synaptic (synaptophysin) and post-synaptic protein (post synaptic density protein 95) expression in brains from transgenic 3XTg-AD mice. Taken together, our data suggest that LISPRO may be a superior form of lithium with improved safety and efficacy as a potential new disease modifying drug for AD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Compostos de Lítio/administração & dosagem , Prolina/administração & dosagem , Administração Oral , Doença de Alzheimer/tratamento farmacológico , Animais , Autofagia , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HeLa , Humanos , Inflamação , Carbonato de Lítio/administração & dosagem , Carbonato de Lítio/sangue , Compostos de Lítio/sangue , Compostos de Lítio/química , Masculino , Camundongos , Camundongos Transgênicos , Microglia/metabolismo , Fagocitose , Fosforilação , Prolina/sangue , Prolina/química , Resultado do Tratamento
17.
Neuromolecular Med ; 19(2-3): 300-308, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28612181

RESUMO

Previous studies have demonstrated that the low-density lipoprotein receptor-related protein-1 (LRP1) plays conflicting roles in Alzheimer's disease (AD) pathogenesis, clearing ß-amyloid (Aß) from the brain while also enhancing APP endocytosis and resultant amyloidogenic processing. We have recently discovered that co-expression of mutant LRP1 C-terminal domain (LRP1-CT C4408R) with Swedish mutant amyloid precursor protein (APPswe) in Chinese hamster ovary (CHO) cells decreases Aß production, while also increasing sAPPα and APP α-C-terminal fragment (α-CTF), compared with CHO cells expressing APPswe alone. Surprisingly, the location of this mutation on LRP1 corresponded with the α-secretase cleavage site of APP. Further experimentation confirmed that in CHO cells expressing APPswe or wild-type APP (APPwt), co-expression of LRP1-CT C4408R decreases Aß and increases sAPPα and α-CTF compared with co-expression of wild-type LRP1-CT. In addition, LRP1-CT C4408R enhanced the unglycosylated form of LRP1-CT and reduced APP endocytosis as determined by flow cytometry. This finding identifies a point mutation in LRP1 which slows LRP1-CT-mediated APP endocytosis and amyloidogenic processing, while enhancing APP α-secretase cleavage, thus demonstrating a potential novel target for slowing AD pathogenesis.


Assuntos
Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Mutação de Sentido Incorreto , Mutação Puntual , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Sequência de Bases , Células CHO , Cricetinae , Cricetulus , Endocitose , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/fisiologia , Domínios Proteicos , Proteínas Recombinantes/metabolismo
18.
Heliyon ; 3(4): e00279, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28413833

RESUMO

Alzheimer's disease (AD), a progressive neurodegenerative disorder, is linked to oxidative stress, altered amyloid precursor protein (APP) proteolysis, tau hyperphosphorylation and the accumulation of amyloid-ß (Aß) plaques and neurofibrillary tangles (NFT). A growing body of evidence suggests that mitochondrial dysfunction can be a key promoter of all of these pathologies and predicts that restoration of mitochondrial function might be a potential therapeutic strategy for AD. Therefore, in the present study, we tested the beneficial effect of a nutraceutical formulation Nutrastem II (Nutra II), containing NT020 (a mitochondrial restorative and antioxidant proprietary formulation) and pyrroloquinolinequinone (PQQ, a stimulator of mitochondria biogenesis) in 5XFAD transgenic mice. Animals were fed Nutra II for 12 weeks, starting at 3 months of age, after which behavioral and neuropathological endpoints were determined. The data from behavioral test batteries clearly revealed that dietary supplementation of Nutra II effectively ameliorated the motor deficiency and cognitive impairment of 5XFAD mice. In addition, Nutra II also protected mitochondrial function in 5XFAD mice brain, as evidenced by declined ROS levels and membrane hyperpolarization, together with elevated ATP levels and respiratory states. Interestingly, while Nutra II treatment only slightly reduced soluble Aß42 levels, this formulation significantly impacted tau metabolism, as shown by reduced total and phosphorylated tau levels of 5XFAD mouse brain. Taken together, these preclinical findings confirm that mitochondrial function may be a key treatment target for AD and that Nutra II should be further investigated as a potential candidate for AD therapy.

19.
J Neurosci Res ; 95(4): 973-991, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27531392

RESUMO

Soluble amyloid precursor protein α (sAPPα), a secreted proteolytic fragment of nonamyloidogenic amyloid precursor protein (APP) processing, is known for numerous neuroprotective functions. These functions include but are not limited to proliferation, neuroprotection, synaptic plasticity, memory formation, neurogenesis, and neuritogenesis in cell culture and animal models. In addition, sAPPα influences amyloid-ß (Aß) production by direct modulation of APP ß-secretase proteolysis as well as Aß-related or unrelated tau pathology, hallmark pathologies of Alzheimer's disease (AD). Thus, the restoration of sAPPα levels and functions in the brain by increasing nonamyloidogenic APP processing and/or manipulation of its signaling could reduce AD pathology and cognitive impairment. It is likely that identification and characterization of sAPPα receptors in the brain, downstream effectors, and signaling pathways will pave the way for an attractive therapeutic target for AD prevention or intervention. © 2016 Wiley Periodicals, Inc.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Doença de Alzheimer/terapia , Animais , Modelos Animais de Doenças , Humanos
20.
J Neuroimmunol ; 299: 98-106, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27725131

RESUMO

Naturally-occurring bioactive flavonoids such as diosmin significantly reduces amyloid beta (Aß) associated pathology in Alzheimer's disease (AD) mouse models. In the present study, oral administration of diosmin reduced cerebral Aß oligomer levels, tau-hyperphosphorylation and cognitive impairment in the 3xTg-AD mouse model through glycogen synthase kinase-3 (GSK-3) and transient receptor potential canonical 6-related mechanisms. Diosmetin, one major bioactive metabolite of diosmin, increased inhibitory GSK-3ß phosphorylation, while selectively reducing γ-secretase activity, Aß generation, tau hyperphosphorylation and pro-inflammatory activation of microglia in vitro, without altering Notch processing. Therefore, both diosmin and diosmetin could be considered as potential candidates for novel anti-AD therapy.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Córtex Cerebral/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Diosmina/uso terapêutico , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Animais , Animais Recém-Nascidos , Células CHO , Córtex Cerebral/efeitos dos fármacos , Disfunção Cognitiva/metabolismo , Cricetinae , Cricetulus , Diosmina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Células HeLa , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Transgênicos , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Proteínas tau/antagonistas & inibidores
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