Target For Alzheimer Research Articles

Comparing Acetylcholinesterase and Butyrylcholinesterase Inhibition Effect of Total Extract and Fractions with Alcaloid-Rich Extract of Huperzia Serrata (Thunb.) Trevis.

Herbal extract, rich with natural compounds, has been used for medicinal purpose such as treating neurological disorders such as cognitive defection for a long period of time, often without significant adverse effects. We compared AChE and BuChE – inhibition effect of total extracts and fractions of Huperzia serrata (Thunb.) Trevis. with alcaloid-rich extract. Our samples were subjected under supersonic extraction with ethanol 50o as solvent and fractionally extracted with n-hexane, EtOAc and n-butanol, respectively; alcaloid-rich extract was collected simutaneously. Ellman’s method was used to assay AChE and BuChE inhibition activity. Results: Alcaloid-rich extraction proved to be the superior AChE inhibiting agent, its activity nearly 6 fold of the most active Huperzia serrata extraction with IC50 value of 7.93 (5.43-10.98) µg/ml. While the fractions as well as the total extract did not provide any BuChE inhibition activity, alcaloid-rich extract showed weak ability (IC50 at 76.67 (64.78 – 91.84) µg/ml). Overall, the superior enzyme inhibition effect of alcaloid-rich extract might open a new approach in preventing and treating neurological disorders such as alzheimer’s.
 Keywords
 Huperzia serrata (Thunb.) Trevis, alcaloid, Acetylcholinesrerase inhibitors (AChE); butyrylcholinesterase (BuChE), Alzheimer.
 References
 [1] Dos Santos Picanco, Leide C et al., Alzheimer's disease: A review from the pathophysiology to diagnosis, new perspectives for pharmacological treatment, Current medicinal chemistry 25(26) (2018) 3141 - 3159. https://doi.org/10.2174/0929867323666161213101126.[2] B.M. McGleenon, K.B. Dynan, A.P. Passmore, Acetylcholinesterase inhibitors in Alzheimer's disease, British journal of clinical pharmacology 48(4) (1999) 471-480. https://10.1046/j.1365-2125.1999.00026.x.[3] Agneta Nordberg, Clive Ballard, Roger Bullock, Taher Darreh-Shori, Monique Somogyi, A review of butyrylcholinesterase as a therapeutic target in the treatment of Alzheimer’s disease, The primary care companion for CNS disorders 15(2) (2013). https://10.4088/PCC.12r01412.[4] N.M. Ha, V.V. Dung et al., Report on the review of Vietnam’s wildlife trade policy, 2007.[5] D.H. Bich, et al., Medicinal plants and medicinal animals in Viet Nam. Science and Technics Publishing House 1 (2011) 896-897 (in Vietnamese).[6] Jia-Sen Liu, Yuan-Long Zhu, Chao-Mei Yu, You-Zuo Zhou, Yan-Yi Han, Feng-Wu Wu, Bao-Feng Qi, The structures of huperzine A and B, two new alkaloids exhibiting marked anticholinesterase activity. Canadian Journal of Chemistry 64(4) (1986) 837-839. https://doi.org/10.1139/v86-137.[7] Takuya Ohba, Yuta Yoshino et al., Japanese Huperzia serrata extract and the constituent, huperzine A, ameliorate the scopolamine-induced cognitive impairment in mice, Bioscience biotechnology and biochemistry 79(11) (2015) 1838-1844. https://doi.org/10.1080/09168451.2015.1052773.[8] Ju-Yeon Park, Hyuck Kim et al., Ethanol Extract of Lycopodium serratum Thunb. Attenuates Lipopolysaccharide-Induced C6 Glioma Cells Migration via Matrix Metalloproteinase-9 Expression, Chinese Journal of Integrative Medicine 24(11) (2018) 860-866. https://doi.org/10.1007/s11655-017-2923-9.[9] M. Maridass, G. Raju, Investigation of phytochemical and antimicrobial activity of Huperzia species, Pharmacologyonline 3 (2009) 688-692.[10] George.L.Ellman, K.Diane Courtney, et al., A new and rapid colorimetric determination of acetylcholinesterase activity, Biochemical Pharmacology 7(2) (1961) 88-95. https://doi.org/10.1016/0006-2952(61)90145-9.[11] Paul T Francis, et al., The cholinergic hypothesis of Alzheimer’s disease: a review of progress. Journal of Neurology, Neurosurgery & Psychiatry, 66(2) (1999) 137-147. http://dx.doi.org/10.1136/jnnp.66.2.137.[12] Prerna Upadhyaya, Vikas Seth, Mushtaq Ahmad, Therapy of Alzheimer’s disease: An update, African Journal of Pharmacy and Pharmacology 4(6) (2010) 408-421.[13] Hachiro Sugimoto, Hiroo Ogura, et al., Research and development of donepezil hydrochloride, a new type of acetylcholinesterase inhibitor, The Japanese journal of pharmacology 89(1) (2002) 7-20.[14] N.T.K. Thu, et al., Acetylcholinesterase and butyrylcholinesterase inhibition effect of fractions extract of Huperzia serrata (Thunb.) Trevis. The journal of Pharmeceutical 56(11) 49-53 (in Vietnamese).[15] Xiaoqiang Ma, Changheng Tan, et al, Is there a better source of huperzine A than Huperzia serrata? Huperzine A content of Huperziaceae species in China. J Agric Food Chem, 53(5) (2005)1393-8. https://doi.org/10.1021/jf048193n.[16] Ya-Bing Yang, Xue-Qiong Yang, et al., A New Flavone Glycoside from Huperzia serrata. Chinese Journal of Natural Medicines 6(6) (2008) 408-410.[17] G.T. Ha, R.K. Wong, Y. Zhang, Huperzine a as potential treatment of Alzheimer's disease: an assessment on chemistry, pharmacology, and clinical studies, Chemistry & biodiversity 8(7) (2011) 1189-1204. https://doi.org/10.1002/cbdv.201000269.[18] H.Y. Zhang, X.C. Tang, Neuroprotective effects of huperzine A: new therapeutic targets for neurodegenerative disease, Trends in pharmacological sciences 27(12) (2006) 619-625. https://doi.org/10.1016/j.tips.2006.10.004.[19] Y. Wang, X.C. Tang, H.Y. Zhang, Huperzine A alleviates synaptic deficits and modulates amyloidogenic and nonamyloidogenic pathways in APPswe/PS1dE9 transgenic mice, Journal of neuroscience research 90(2) (2012) 508-517. https://doi.org/10.1002/jnr.22775.[20] C.Y. Wang, et al., Huperzine A activates Wnt/β-catenin signaling and enhances the nonamyloidogenic pathway in an Alzheimer transgenic mouse model, Neuropsychopharmacology 36(5) (2011) 1073-1089. https://doi.org/10.1038/npp.2010.245.[21] R.K. Gordon, et al., The NMDA receptor ion channel: a site for binding of Huperzine A, Journal of applied toxicology 21(S1) (2001) S47-S51. https://doi.org/10.1002/jat.805.[22] M. Rafii, et al., A phase II trial of huperzine A in mild to moderate Alzheimer disease, Neurology 76(16) (2011) 1389-1394. https://doi.org/10.1212/WNL.0b013e318216eb7b.[23] N.H. Greig, et al., A new therapeutic target in Alzheimer's disease treatment: attention to butyrylcholinesterase, Current medical research and opinion 17(3) (2001)1 59-165.[24] A. Ferreira, et al., Huperzine A from Huperzia serrata: a review of its sources, chemistry, pharmacology and toxicology, Phytochemistry reviews 15(1) (2016) 51-85. https://doi.org/10.1007/s11101-014-9384-y.

Insulin signaling as a therapeutic target in Alzheimer’s disease: Efficacy of apomorphine

AbstractAlzheimer's disease has recently been characterized as “diabetes of the brain” or “type 3 diabetes.” Although recent clinical trials targeting amyloid β‐protein have been unsuccessful, glucose‐insulin metabolism in the brain may provide an alternative therapeutic target. In this review, we focus on three related topics: (a) how peripheral and brain insulin resistance interact with each other; (b) brain insulin resistance as a promising therapeutic target for Alzheimer's disease and anti‐diabetic drugs as potentially effective drugs; and (c) apomorphine as a novel drug that improves neuronal insulin signaling. Although apomorphine is a dopamine receptor agonist, studies in our laboratory revealed a novel effect, promoting intracellular amyloid β degradation and improving memory function in an Alzheimer's disease mouse model. Recently, we demonstrated that apomorphine treatment improved neuronal insulin resistance and activated insulin‐degrading enzyme, a major amyloid β‐degrading enzyme. In addition, we confirmed the efficacy of apomorphine for some Alzheimer's disease patients. In this context, combined treatment involving anti‐diabetic drugs and apomorphine may provide an effective therapeutic approach for Alzheimer's disease.

PET imaging of mGluR5 in Alzheimer\u2019s disease

BackgroundMetabotropic glutamate subtype 5 receptors (mGluR5) modulate synaptic transmission and may constitute an important therapeutic target in Alzheimer’s disease (AD) by mediating the synaptotoxic action of amyloid-β oligomers. We utilized the positron emission tomography (PET) radioligand [18F]FPEB to investigate mGluR5 binding in early AD.MethodsSixteen individuals with amnestic mild cognitive impairment (MCI) due to AD or mild AD dementia who were positive for brain amyloid were compared to 15 cognitively normal (CN) participants who were negative for brain amyloid. Diagnostic groups were well balanced for age, sex, and education. Dynamic PET scans were acquired for 60 min, starting at 60 min after the initial administration of up to 185 MBq of [18F]FPEB using a bolus-plus-constant-infusion method (Kbol = 190 min). Equilibrium modeling with a cerebellum reference region was used to estimate [18F]FPEB binding (BPND) to mGluR5. Analyses were performed with and without corrections for gray matter atrophy and partial volume effects.ResultsLinear mixed model analysis demonstrated a significant effect of group (p = 0.011) and the group × region interaction (p = 0.0049) on BPND. Post hoc comparisons revealed a significant reduction (43%) in mGluR5 binding in the hippocampus of AD (BPND = 0.76 ± 0.41) compared to CN (BPND = 1.34 ± 0.58, p = 0.003, unpaired t test) participants, and a nonsignificant trend for a reduction in a composite association cortical region in AD (BPND = 1.57 ± 0.25) compared to CN (BPND = 1.86 ± 0.63, p = 0.093) participants. Exploratory analyses suggested additional mGluR5 reductions in the entorhinal cortex and parahippocampal gyrus in the AD group. In the overall sample, hippocampal mGluR5 binding was associated with episodic memory scores and global function.Conclusions[18F]FPEB-PET revealed reductions in hippocampal mGluR5 binding in early AD. Quantification of mGluR5 binding in AD may expand our understanding of AD pathogenesis and accelerate the development of novel biomarkers and treatments.

Cross Talk between Mitochondria and Other Targets in Alzheimer's Disease.

Among the neurodegenerative diseases, Alzheimer's disease (AD) is a predominant public health issue, affecting 16 million people around the world. It is clinically manifested by the presence of amyloid plaques (Aβ) and neurofibrillary tangles (NFT) within the brain. Due to intraneuronal processing, Aβ interacts with cellular targets such as mitochondria, ER, and Golgi apparatus and hampers their normal functions. Alteration in the mitochondrial function, closely related to the production of reactive oxygen species (ROS), Ca+2 overload, and apoptosis in the brain, is one of the key pathological events studied in AD pathogenesis. It is also an important pivot for the intracellular interaction with ER and Golgi through signal transduction and membrane contact to regulate cell survival and death mechanism. Alteration in mitochondrial function is intimately connected with abnormal ER or Golgi function. Stimuli that enhance perturbation in the normal ER or Golgi organelles function can involve mitochondria mediated apoptotic cell death. In this review, we address the importance of the mitochondria and their cross talk with ER and Golgi in AD pathogenesis and animal models with a therapeutic strategy to improve the mitochondrial functions.

Adiponectin Paradox as a Therapeutic Target in Alzheimer's Disease.

Despite the apparent neurotoxicity of amyloid-β (Aβ), recent clinical trials of Aβ immunotherapy have not shown any clinical benefit in Alzheimer’s disease (AD). Given this, clarification of the next generation therapeutic strategy in AD is warranted. Hypothetically, adiponectin might be involved in promoting amyloidogenic evolvability in reproduction, which may result in the adiponectin paradox through antagonistic pleiotropy mechanism in aging, leading to AD. Accordingly, preventing the adiponectin paradox by suppressing adiponectin signaling might prove therapeutic in AD.

Role of neprilysin in synaptic plasticity and memory

Neprilysin (NEP, neutral endopeptidase, endopeptidase-24.11) is an important enzyme being most abundant in the kidney and liver and participating in the degradation of a variety of biologically active peptides. It is essential for the regulation of blood pressure and the normal function of practically all organs in the body, and its dysregulation contributes to the development of such diseases like heart failure, cancer, diabetes, and chronic inflammation. It is also a critical neuropeptidase that terminates the action of various neuropeptides such as enkephalins, substance P, somatostatin, which participate in signaling and regulatory events in the brain. NEP is a major amyloid-degrading enzyme, which makes it an important therapeutic target in Alzheimer's disease (AD). Our studies have revealed that NEP expression declines with age in the brain structures participating in memory and which are mainly affected by AD pathogenesis. Moreover, NEP expression decreases under hypoxic conditions, and prenatal hypoxia leads to its deficit in some brain structures both during development and adulthood, which correlates with a reduced number of labile dendritic spines and cognitive deficit in rats. Using the model of prenatal hypoxia in rats, we have tested the effectiveness of several compounds (inhibitors of caspases, histone deacetylases, tyrosine kinases or nuclear retinoid X receptor agonists as well as an antioxidant, epigallocatechin gallate) which, via different mechanisms, were able to restore NEP expression and activity reduced after prenatal hypoxia and improve cognitive functions in rats. In this paper, we provide an overview of the literature and our data on the role of NEP in synaptic plasticity, neuronal activity, and cognitive functions and outline current approaches to regulate its expression and activity in the brain.

The inhibitory effects of bile acids on catalytic and non-catalytic functions of acetylcholinesterase as a therapeutic target in Alzheimer’s disease

Acetylcholine is a fast-acting neurotransmitter in synapses and neuromuscular junctions that is decreased in Alzheimer's disease (AD) by hyper‑activation of acetylcholinesterase (AChE), which leads to progressive loss of memory and neurobehavioral abnormalities. Therefore, AChE inhibitors have therapeutic potential in AD that could include natural compounds such as bile acids. Bile acids, as potent molecules, could improve some types of neurodegenerative diseases via antioxidant effects and other unknown mechanisms. The aim of this study was to investigate beneficial effects of bile acids on AChE catalytic and non‑catalytic functions, amyloid plaque deposit and memory in a rat model of AD. The effects of sodium deoxycholate and cholic acid on AChE activity were assessed by in vitro assay. Then, the bile acids' potential therapeutic effects were investigated on nucleus basalis of Meynert lesioned rats using behavioral evaluation, biochemical tests and histological methods. Molecular docking simulation was also implemented to investigate the possible interaction between bile acids and AChE. According to the in vitro and in vivo results, sodium deoxycholate could efficiently inhibit the catalytic function of the enzyme by interacting with the catalytic site, while cholic acid interacted with the peripheral anionic site and inhibited chaperone activity of the enzyme that led to the reduced amyloid plaque deposition. The co‑administration of cholic acid and sodium deoxycholate showed these compounds are able to simultaneously inhibit the catalytic and non‑catalytic functions of the enzyme. This study clarifies the roles of natural bile acids in the nervous system and in AChE function through multiple experimental and simulation methods.

Engineering mesenchymal stromal/stem cell-derived extracellular vesicles with improved targeting and therapeutic efficiency for the treatment of central nervous system disorders.

Engineering mesenchymal stromal/stem cell-derived extracellular vesicles with improved targeting and therapeutic efficiency for the treatment of central nervous system disorders.

P-glycoprotein: a role in the export of amyloid-β in Alzheimer's disease?

The accumulation of amyloid-β (Aβ) peptides is a key histopathological feature of the Alzheimer's brain. Defective clearance mechanisms result in toxic levels of soluble Aβ40 and Aβ42 oligomers, leading to impaired synaptic function, neurodegeneration and cognitive decline. Growing evidence points to the involvement of P-glycoprotein (P-gp or ABCB1), an ATP-binding cassette transporter highly expressed on the luminal side of the blood-brain barrier, in facilitating the clearance of Aβ from the brain. In this review, we summarise evidence from human, animal and invitro studies examining the contribution of P-gp to Aβ clearance, and discuss the potential for P-gp as a novel pharmacological target in Alzheimer's disease (AD). P-gp expression and activity in the brain are inversely correlated with ageing, Aβ deposition and AD. Moreover, Aβ itself has been found to compromise the expression of P-gp, thereby exacerbating Aβ deposition and disease. Despite decades of research, the pathophysiology of AD remains elusive. Understanding the normal versus impaired processing and clearance mechanisms affecting Aβ peptides will assist the development of more effective therapeutic agents to combat this progressive neurodegenerative condition that continues to devastate millions of patients globally.

COMBINING MACHINE LEARNING WITH AUTOMATED NEMATODE LIFESPAN ANALYSIS TO IDENTIFY MODIFIERS OF ALZHEIMER’S DISEASE

Here we present new computational and experimental methods to leverage the gene expression and neuropathology data collected from several large-scale studies of Alzheimer’s disease . These data sets include diverse data types, including transcriptomics, neuropathology phenotypes such as quantification of amyloid beta plaques and tau tangles in different brain regions, as well as assessments of dementia prior to death. This meta-analysis is a complex undertaking because the available data are from different studies and/or brain regions involving study-specific confounders and/or region-specific biological processes. We have therefore taken neural network and probabilistic computational approaches that reduce the data dimensionality, allowing statistical comparison across all brain samples. These approaches identify gene expression changes that are significantly associated with clinical and neuropathological assessment of Alzheimer’s disease. We then conduct in vivo validation of the genes through genetic screening of C. elegans models of Alzheimer's disease utilizing our automated robotic lifespan analysis platform. This approach allows for the greater leverage of existing Alzheimer’s disease biobank data to identify deep genetic signatures that could help identify new clinical gene-expression markers and pharmacological targets for Alzheimer’s disease.

A New Kid on the Block? Carbonic Anhydrases as Possible New Targets in Alzheimer's Disease.

The increase in the incidence of neurodegenerative diseases, in particular Alzheimer’s Disease (AD), is a consequence of the world′s population aging but unfortunately, existing treatments are only effective at delaying some of the symptoms and for a limited time. Despite huge efforts by both academic researchers and pharmaceutical companies, no disease-modifying drugs have been brought to the market in the last decades. Recently, several studies shed light on Carbonic Anhydrases (CAs, EC 4.2.1.1) as possible new targets for AD treatment. In the present review we summarized preclinical and clinical findings regarding the role of CAs and their inhibitors/activators on cognition, aging and neurodegeneration and we discuss future challenges and opportunities in the field.

Effects of natural compounds on conformational properties and hairpin formation of amyloid-β42 monomer: docking and molecular dynamics simulation study

The β42 amyloid peptides (Aβ) are identified as a candidate target for Alzheimer’s drugs. Phenolic compounds can bind to the Aβ and inhibit amyloid formation. However, the inhibitory mechanism of phenolic compounds remains unclear. In this study, the molecular dynamic simulation and docking program were used to characterize the molecular details of inhibitory mechanism of the phenolic compounds. Our Results show that the phenolic compounds can bind to hydrophobic region in Aβ42 monomer and alter hydrophobic interactions network at Aβ42 which play a key role in β-sheet formation. The cluster analysis and interactions network analysis were used to probe conformational changes in Aβ42. In most populated clusters of Aβ42-phenolic compounds complexes, the sheet structures were not observed or reduced. It seems that the binding of phenolic compounds can induce larger conformational diversity for amyloid peptide and changes conformational properties of amyloid peptide. The phenolic compounds can deform β-Hairpin structure of Aβ by destabilizing salt bridges E22-K28 and D23-K28 which can alter the conformation of Aβ42 in aqueous solution. These findings are in accordance with experimental results, to some extent give a molecular level interpretation for the inhibitory mechanism of phenolic compounds .In addition, this study may add important new details to the inhibitory mechanism of Alzheimer’s drug.Communicated by Ramaswamy H. Sarma

Benzimidazole-derived Compounds Designed for Different Targets of Alzheimer’s Disease

Benzimidazole scaffold has been efficiently used for the design of various pharmacologically active molecules. Indeed, there are various benzimidazole drugs, available today, employed for the treatment of different diseases. Although there is no benzimidazole moiety containing a drug used in clinic today for the treatment of Alzheimer's Disease (AD), there have been many benzimidazole derivative compounds designed and synthesized to act on some of the validated and non-validated targets of AD. This paper aims to review the literature to describe these benzimidazole containing molecules designed to target some of the biochemical cascades shown to be involved in the development of AD.

Innovative Therapeutic Potential of Cannabinoid Receptors as Targets in Alzheimer's Disease and Less Well-Known Diseases.

The discovery of cannabinoid receptors at the beginning of the 1990s, CB1 cloned in 1990 and CB2 cloned in 1993, and the availability of selective and potent cannabimimetics could only be justified by the existence of endogenous ligands that are capable of binding to them. Thus, the characterisation and cloning of the first cannabinoid receptor (CB1) led to the isolation and characterisation of the first endocannabinoid, arachidonoylethanolamide (AEA), two years later and the subsequent identification of a family of lipid transmitters known as the fatty acid ester 2-arachidonoylglycerol (2-AG). The endogenous cannabinoid system is a complex signalling system that comprises transmembrane endocannabinoid receptors, their endogenous ligands (the endocannabinoids), the specific uptake mechanisms and the enzymatic systems related to their biosynthesis and degradation. The endocannabinoid system has been implicated in a wide diversity of biological processes, in both the central and peripheral nervous systems, including memory, learning, neuronal development, stress and emotions, food intake, energy regulation, peripheral metabolism, and the regulation of hormonal balance through the endocrine system. In this context, this article will review the current knowledge of the therapeutic potential of cannabinoid receptor as a target in Alzheimer's disease and other less well-known diseases that include, among others, multiple sclerosis, bone metabolism, and Fragile X syndrome. The therapeutic applications will be addressed through the study of cannabinoid agonists acting as single drugs and multi-target drugs highlighting the CB2 receptor agonist.

Multitarget Approach for the Treatment of Alzheimer’s Disease: Inhibition of Phosphodiesterase 9 (PDE9) and Histone Deacetylases (HDACs) Covering Diverse Selectivity Profiles

Here, we present a series of dual-target phosphodiesterase 9 (PDE9) and histone deacetylase (HDAC) inhibitors devised as pharmacological tool compounds for assessing the implications of these two targets in Alzheimer's disease (AD). These novel inhibitors were designed taking into account the key pharmacophoric features of known selective PDE9 inhibitors as well as privileged chemical structures, bearing zinc binding groups (hydroxamic acids and ortho-amino anilides) that hit HDAC targets. These substituents were selected according to rational criteria and previous knowledge from our group to explore diverse HDAC selectivity profiles (pan-HDAC, HDAC6 selective, and class I selective) that were confirmed in biochemical screens. Their functional response in inducing acetylation of histone and tubulin and phosphorylation of cAMP response element binding (CREB) was measured as a requisite for further progression into complete in vitro absorption, distribution, metabolism and excretion (ADME) and in vivo brain penetration profiling. Compound 31b, a selective HDAC6 inhibitor with acceptable brain permeability, was chosen for assessing in vivo efficacy of these first-in-class inhibitors, as well as studying their mode of action (MoA).

Identification of molecular signatures and pathways to identify novel therapeutic targets in Alzheimer's disease: Insights from a systems biomedicine perspective

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. However, there are no peripheral biomarkers available that can detect AD onset. This study aimed to identify the molecular signatures in AD through an integrative analysis of blood gene expression data. We used two microarray datasets (GSE4226 and GSE4229) comparing peripheral blood transcriptomes of AD patients and controls to identify differentially expressed genes (DEGs). Gene set and protein overrepresentation analysis, protein-protein interaction (PPI), DEGs-Transcription Factors (TFs) interactions, DEGs-microRNAs (miRNAs) interactions, protein-drug interactions, and protein subcellular localizations analyses were performed on DEGs common to the datasets. We identified 25 common DEGs between the two datasets. Integration of genome scale transcriptome datasets with biomolecular networks revealed hub genes (NOL6, ATF3, TUBB, UQCRC1, CASP2, SND1, VCAM1, BTF3, VPS37B), common transcription factors (FOXC1, GATA2, NFIC, PPARG, USF2, YY1) and miRNAs (mir-20a-5p, mir-93-5p, mir-16-5p, let-7b-5p, mir-708-5p, mir-24-3p, mir-26b-5p, mir-17-5p, mir-193-3p, mir-186-5p). Evaluation of histone modifications revealed that hub genes possess several histone modification sites associated with AD. Protein-drug interactions revealed 10 compounds that affect the identified AD candidate biomolecules, including anti-neoplastic agents (Vinorelbine, Vincristine, Vinblastine, Epothilone D, Epothilone B, CYT997, and ZEN-012), a dermatological (Podofilox) and an immunosuppressive agent (Colchicine). The subcellular localization of molecular signatures varied, including nuclear, plasma membrane and cytosolic proteins.In the present study, it was identified blood-cell derived molecular signatures that might be useful as candidate peripheral biomarkers in AD. It was also identified potential drugs and epigenetic data associated with these molecules that may be useful in designing therapeutic approaches to ameliorate AD.

The Critical Role of Nurr1 as a Mediator and Therapeutic Target in Alzheimer's Disease-related Pathogenesis.

Several studies have revealed that the transcription factor nuclear receptor related 1 (Nurr1) plays several roles not only in the regulation of gene expression related to dopamine synthesis, but also in alternative splicing, and miRNA targeting. Moreover, it regulates cognitive functions and protects against inflammation-induced neuronal death. In particular, the role of Nurr1 in the pathogenesis of Parkinson’s disease (PD) has been well investigated; for example, it has been shown that it restores behavioral and histological impairments in PD models. Although many studies have evaluated the connection between Nurr1 and PD pathogenesis, the role of Nurr1 in Alzheimer’s disease (AD) remain to be studied. There have been several studies describing Nurr1 protein expression in the AD brain. However, only a few studies have examined the role of Nurr1 in the context of AD. Therefore, in this review, we highlight the overall effects of Nurr1 under the neuropathologic conditions related to AD. Furthermore, we suggest the possibility of using Nurr1 as a therapeutic target for AD or other neurodegenerative disorders.

Genetic and Real-World Clinical Data, Combined with Empirical Validation, Nominate Jak-Stat Signaling as a Target for Alzheimer's Disease Therapeutic Development.

As genome-wide association studies (GWAS) have grown in size, the number of genetic variants that have been associated per disease has correspondingly increased. Despite this increase in the number of single-nucleotide polymorphisms (SNPs) identified per disease, their biological interpretation has in many cases remained elusive. To address this, we have combined GWAS results with orthogonal sources of evidence, namely the current knowledge of molecular pathways; real-world clinical data from six million patients; RNA expression across tissues from Alzheimer’s disease (AD) patients, and purpose-built rodent models for experimental validation. In more detail, first we show that when examined at a pathway level, analysis of all GWAS studies groups AD in a cluster with disorders of immunity and inflammation. Using clinical data, we show that the degree of comorbidity of these diseases with AD correlates with the strength of their genetic association with molecular participants in the Janus kinases/signal transducer and activator of transcription (JAK-STAT) pathway. Using four independent RNA expression datasets we then find evidence for the altered regulation of JAK-STAT pathway genes in AD. Finally, we use both in vitro and in vivo rodent models to demonstrate that Aβ induces gene expression of the key drivers of this pathway, providing experimental evidence to validate these data-driven observations. These results therefore nominate JAK-STAT anomalies as a prominent aetiopathological event in AD and hence a potential target for therapeutic development, and moreover demonstrate a de novo multi-modal approach to derive information from rapidly increasing genomic datasets.

The long-non-coding RNA NEAT1 is a novel target for Alzheimer’s disease progression via miR-124/BACE1 axis

ABSTRACTObjectives: Long-non-coding RNAs (lncRNAs) have been involved in central nervous system recently. A number of studies have reported that lncRNA NEAT1 exerts critical roles in neurodegenerative disorder. Beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) has been reported to exert function in the accumulation of amyloid-β (Aβ). Moreover, BACE1 acts as a target of miR-124 in the progression of AD. So far, the biological role and underlying mechanisms of NEAT1 and miR-124 in AD remains elusive.Methods: The relative NEAT1 and miR-124 expression was examined by qRT-PCR in the tissues and cells line of AD. Cell apoptosis was examined by FACS. Luciferase reporter assay was performed to verify that miR-124 is a direct target of NEAT1, and BACE1 is a downstream target of miR-124. qRT-PCR and western blot analysis were also performed to determinate the BACE1 and the phosphorylation of tau protein.Results: NEAT1 was notably up-regulated and miR-124 was remarkably down-regulated in AD mouse model. Knockdown of NEAT1 or overexpression of miR-124 showed the protective effects on cellular AD model induced by Aβ. Moreover, miR-124 expression could be up- and down-regulated by suppression or overexpression of NEAT1, respectively. In addition, the expression of BACE1 was the potential functional target of miR-124. These findings suggested that NEAT1 might play a vital role in the development of AD by regulating miR-124/BACE1 axis.Discussion: The present study showed that NEAT1 worked as a regulating factor to promote the development of AD via modulating miR-124/BACE1 axis, which might be considered as a novel target in AD treatment.

Common Non‐East Asian Aldehyde Dehydrogenase 2 Deficiencies; Potential Drug Target for Alzheimer's Disease and Mitochondrial Dysfunction

Aldehyde dehydrogenase 2 (ALDH2) catalyzes the oxidation and detoxification of aliphatic aldehydes, including acetaldehyde. About 40% of East Asians carry a single point mutation in ALDH2*2 (E504K) that contributes to a severe enzyme deficiency and accumulation of toxic reactive aldehydes. We previously identified Alda‐1 (an aldehyde dehydrogenase activator) that reduces aldehydic load by increasing the catalytic activity and stability of wild type enzyme and by correcting the structural defect in ALDH2*2, in vitro and in vivo. Using the ExAC genomic database, we identified and characterized new ALDH2 variants in several non‐East Asian populations. Nine other ALDH2 variants with a single point mutation were identified among Latino, African, and Finnish ethnic groups at a frequency of >1/1000. We focused on three variants, two with a reported frequency of 2.5% and one with a reported frequency of 1.2%. All three newly‐identified ALDH2 mutants exhibited a significant reduction in activity as compared with wild type enzyme (ALDH2*1/*1; WT) but differed in their sensitivity to Alda‐1‐induced activation as determined in vitro and in 3T3 cells overexpressing each of the variants. Acetaldehyde‐induced toxicity (mitochondrial dysfunction and cell death) was also higher in these cells relative to 3T3 cells overexpressing WT ALDH2. Recent evidence suggests a correlation between increased aldehydic load and Alzheimer's disease. In line with this evidence, there was a greater mitochondrial dysfunction and cell toxicity induced by oligomeric amyloid beta1‐42 (oAb1‐42) in 3T3 cells expressing inactive variants of ALDH2 relative to WT enzyme. These defects were reduced by Alda‐1 co‐treatment. Ethanol, which is consumed by ~80% of the world's population, increases aldehydic load. Using ALDH2*2 knockin mice, we found that chronic exposure to ethanol (1g/kg/day) for 11 weeks increased oxidative stress, apoptosis, and Ab1‐42 accumulation in their brains relative to WT mice. Co‐treatment with Alda‐1 (10mg/kg/day) significantly reduced these toxic effects in both WT and ALDH2*2 mice. Finally, treatment of Alzheimer's disease patient‐derived fibroblasts with 0.1% ethanol resulted in a higher mitochondrial dysfunction and cytotoxicity relative to fibroblasts of healthy subjects. These effects were reduced by co‐treatment with Alda‐1, even in cells overexpressing ALDH2*2.In conclusion, ALDH2 deficiencies are much more common than previously thought, possibly affecting >10% of people worldwide. As aldehydic load contributes to many chronic diseases, including Alzheimer's disease, drugs that activate ALDH2 and correct the functional deficiency may provide benefit to those at risk.Support or Funding InformationSupported by NIAAA11147 R37 Merit award to DM‐RThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.