scholarly journals “Ready for What?”: Timing and Speculation in Alzheimer’s Disease Drug Development

2021 ◽  
pp. 016224392110071
Author(s):  
Natassia F. Brenman ◽  
Richard Milne
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Drug Development ◽  
Clinical Trial Design ◽  
Discursive Construction ◽  
Biological Time ◽  
Temporal Specificity ◽  
Adaptive Trials ◽  
The Right

“Readiness cohorts” are an innovation in clinical trial design to tackle the scarcity of time and people in drug studies. This has emerged in response to the challenges of recruiting the “right” research participants at the “right time” in the context of precision medicine. In this paper, we consider how the achievement of “readiness” aligns temporalities, biologies, and market processes of pharmaceutical innovation: how the promise of “willing bodies” in research emerges in relation to intertwined economic and biological time imperatives. Drawing on long-term engagement with the field of Alzheimer’s disease prevention and interviews with researchers from academia and the pharmaceutical industry, we describe the discursive construction and practical arrangement of readiness. This paper contributes to understandings of temporal specificity, or “timing,” within prevention research and casts critical light on the way this specificity—the threshold for “trial readiness”—relates to an opaque and highly speculative drug development pipeline. Extending the study of biomedical potential, as that which holds promise but may not yet exist, we consider how absences operate in adaptive trials. By highlighting these absences (“ready for what?”), we outline an opportunity for socio-ethical research to intervene in the speculative gaps of drug development.

Integrated Biomarkers for Depression in Alzheimer’s Disease: A Critical Review

2017 ◽  
Vol 14 (4) ◽  
pp. 441-452 ◽  
Author(s):  
Sofia Wenzler ◽  
Christian Knochel ◽  
Ceylan Balaban ◽  
Dominik Kraft ◽  
Juliane Kopf ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Affect Regulation ◽  
Current Evidence ◽  
Diagnostic Process ◽  
Neuropsychiatric Manifestation ◽  
The Brain ◽  
Control Functional

Depression is a common neuropsychiatric manifestation among Alzheimer’s disease (AD) patients. It may compromise everyday activities and lead to a faster cognitive decline as well as worse quality of life. The identification of promising biomarkers may therefore help to timely initiate and improve the treatment of preclinical and clinical states of AD, and to improve the long-term functional outcome. In this narrative review, we report studies that investigated biomarkers for AD-related depression. Genetic findings state AD-related depression as a rather complex, multifactorial trait with relevant environmental and inherited contributors. However, one specific set of genes, the brain derived neurotrophic factor (BDNF), specifically the Val66Met polymorphism, may play a crucial role in AD-related depression. Regarding neuroimaging markers, the most promising findings reveal structural impairments in the cortico-subcortical networks that are related to affect regulation and reward / aversion control. Functional imaging studies reveal abnormalities in predominantly frontal and temporal regions. Furthermore, CSF based biomarkers are seen as potentially promising for the diagnostic process showing abnormalities in metabolic pathways that contribute to AD-related depression. However, there is a need for standardization of methodological issues and for replication of current evidence with larger cohorts and prospective studies.

Old Drugs with New Tricks; Paradigm in Drug Development Pipeline for Alzheimer’s Disease

2020 ◽  
Vol 20 ◽  
Author(s):  
Tanay Dalvi ◽  
Bhaskar Dewangan ◽  
Rudradip Das ◽  
Jyoti Rani ◽  
Suchita Dattatray Shinde ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Drug Development ◽  
Molecular Targets ◽  
Drug Repurposing ◽  
Phase Iii ◽  
Complex Nature ◽  
New Drug ◽  
Development Pipeline ◽  
Old Drugs

: The most common reason behind dementia is Alzheimer’s disease (AD) and it is predicted to be the third lifethreatening disease apart from stroke and cancer for the geriatric population. Till now only four drugs are available in the market for symptomatic relief. The complex nature of disease pathophysiology and lack of concrete evidences of molecular targets are the major hurdles for developing new drug to treat AD. The the rate of attrition of many advanced drugs at clinical stages, makes the de novo discovery process very expensive. Alternatively, Drug Repurposing (DR) is an attractive tool to develop drugs for AD in a less tedious and economic way. Therefore, continuous efforts are being made to develop a new drug for AD by repursing old drugs through screening and data mining. For example, the survey in the drug pipeline for Phase III clinical trials (till February 2019) which has 27 candidates, and around half of the number are drugs which have already been approved for other indications. Although in the past the drug repurposing process for AD has been reviewed in the context of disease areas, molecular targets, there is no systematic review of repurposed drugs for AD from the recent drug development pipeline (2019-2020). In this manuscript, we are reviewing the clinical candidates for AD with emphasis on their development history including molecular targets and the relevance of the target for AD.

NF-κB as a Key Mediator of Brain Inflammation in Alzheimer’s Disease

2019 ◽  
Vol 18 (1) ◽  
pp. 3-10 ◽  
Author(s):  
Chul Ju Hwang ◽  
Dong-Young Choi ◽  
Mi Hee Park ◽  
Jin Tae Hong
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Treatment Strategies ◽  
Close Correlation ◽  
Specific Protein ◽  
Brain Inflammation ◽  
Cytokines And Chemokines ◽  
Inflammatory Drugs ◽  
Peptide Fibrils

Alzheimer’s disease is the most common form of dementia. It is characterized by betaamyloid peptide fibrils which are extracellular deposition of a specific protein, accompanied by extensive neuroinflammation. Various studies show the presence of a number of inflammation markers in the AD brain: elevated inflammatory cytokines and chemokines, and an accumulation of activated microglia in the damaged regions. NF-κB is a family of redox sensitive transcriptional factors, and it is known that NF-κB has binding sites in the promoter region of the genes involved in amyloidogenesis and inflammation. Long-term use of non-steroidal anti-inflammatory drugs prevents progression of AD and delays its onset, suggesting that there is a close correlation between NF-κB and AD pathogenesis. This study aims to (1) assess the association between NF-κB activity and AD through discussion of a variety of experimental and clinical studies on AD and (2) review treatment strategies designed to treat or prevent AD with NF-κB inhibitors.

Neurobehavioral Consequences Associated with Long Term Tramadol Utilization and Pathological Mechanisms

2020 ◽  
Vol 18 (10) ◽  
pp. 758-768 ◽  
Author(s):  
Khadga Raj ◽  
Pooja Chawla ◽  
Shamsher Singh
Keyword(s):  
Alzheimer’S Disease ◽  
Parkinson’S Disease ◽  
Alzheimer's Disease ◽  
Parkinson's Disease ◽  
Serotonin Reuptake ◽  
Selective Serotonin Reuptake Inhibitors ◽  
Serotonin Syndrome ◽  
Dopamine Synthesis ◽  
Synthetic Analog

: Tramadol is a synthetic analog of codeine used to treat pain of moderate to severe intensity and is reported to have neurotoxic potential. At therapeutic dose, tramadol does not cause major side effects in comparison to other opioid analgesics, and is useful for the management of neurological problems like anxiety and depression. Long term utilization of tramadol is associated with various neurological disorders like seizures, serotonin syndrome, Alzheimer’s disease and Parkinson’s disease. Tramadol produces seizures through inhibition of nitric oxide, serotonin reuptake and inhibitory effects on GABA receptors. Extensive tramadol intake alters redox balance through elevating lipid peroxidation and free radical leading to neurotoxicity and produces neurobehavioral deficits. During Alzheimer’s disease progression, low level of intracellular signalling molecules like cGMP, cAMP, PKC and PKA affect both learning and memory. Pharmacologically tramadol produces actions similar to Selective Serotonin Reuptake Inhibitors (SSRIs), increasing the concentration of serotonin, which causes serotonin syndrome. In addition, tramadol also inhibits GABAA receptors in the CNS has been evidenced to interfere with dopamine synthesis and release, responsible for motor symptoms. The reduced level of dopamine may produce bradykinesia and tremors which are chief motor abnormalities in Parkinson’s Disease (PD).

Recent Updates in the Alzheimer’s Disease Etiopathology and Possible Treatment Approaches: A Narrative Review of Current Clinical Trials

2020 ◽  
Vol 13 (4) ◽  
pp. 273-294 ◽  
Author(s):  
Elahe Zarini-Gakiye ◽  
Javad Amini ◽  
Nima Sanadgol ◽  
Gholamhassan Vaezi ◽  
Kazem Parivar
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Clinical Trials ◽  
Small Molecules ◽  
Clinical Trial Design ◽  
Treatment Approaches ◽  
Drug Candidates ◽  
Novel Treatments ◽  
Approved Drugs ◽  
Tau Aggregation

Background: Alzheimer’s disease (AD) is the most frequent subtype of incurable neurodegenerative dementias and its etiopathology is still not clearly elucidated. Objective: Outline the ongoing clinical trials (CTs) in the field of AD, in order to find novel master regulators. Methods: We strictly reviewed all scientific reports from Clinicaltrials.gov and PubMed databases from January 2010 to January 2019. The search terms were “Alzheimer's disease” or “dementia” and “medicine” or “drug” or “treatment” and “clinical trials” and “interventions”. Manuscripts that met the objective of this study were included for further evaluations. Results: Drug candidates have been categorized into two main groups including antibodies, peptides or hormones (such as Ponezumab, Interferon β-1a, Solanezumab, Filgrastim, Levemir, Apidra, and Estrogen), and naturally-derived ingredients or small molecules (such as Paracetamol, Ginkgo, Escitalopram, Simvastatin, Cilostazo, and Ritalin-SR). The majority of natural candidates acted as anti-inflammatory or/and anti-oxidant and antibodies exert their actions via increasing amyloid-beta (Aβ) clearance or decreasing Tau aggregation. Among small molecules, most of them that are present in the last phases act as specific antagonists (Suvorexant, Idalopirdine, Intepirdine, Trazodone, Carvedilol, and Risperidone) or agonists (Dextromethorphan, Resveratrol, Brexpiprazole) and frequently ameliorate cognitive dysfunctions. Conclusion: The presences of a small number of candidates in the last phase suggest that a large number of candidates have had an undesirable side effect or were unable to pass essential eligibility for future phases. Among successful treatment approaches, clearance of Aβ, recovery of cognitive deficits, and control of acute neuroinflammation are widely chosen. It is predicted that some FDA-approved drugs, such as Paracetamol, Risperidone, Escitalopram, Simvastatin, Cilostazoand, and Ritalin-SR, could also be used in off-label ways for AD. This review improves our ability to recognize novel treatments for AD and suggests approaches for the clinical trial design for this devastating disease in the near future.

Learning Deficits Accompanied by Microglial Proliferation After the Long-Term Post-Injection of Alzheimer’s Disease Brain Extract in Mouse Brains

2021 ◽  
Vol 79 (4) ◽  
pp. 1701-1711
Author(s):  
Tetsuo Hayashi ◽  
Shotaro Shimonaka ◽  
Montasir Elahi ◽  
Shin-Ei Matsumoto ◽  
Koichi Ishiguro ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Mouse Brain ◽  
Functional Decline ◽  
Brain Regions ◽  
Insoluble Fraction ◽  
Brain Extract ◽  
Post Injection ◽  
Learning Deficits

Background: Human tauopathy brain injections into the mouse brain induce the development of tau aggregates, which spread to functionally connected brain regions; however, the features of this neurotoxicity remain unclear. One reason may be short observational periods because previous studies mostly used mutated-tau transgenic mice and needed to complete the study before these mice developed neurofibrillary tangles. Objective: To examine whether long-term incubation of Alzheimer’s disease (AD) brain in the mouse brain cause functional decline. Methods: We herein used Tg601 mice, which overexpress wild-type human tau, and non-transgenic littermates (NTg) and injected an insoluble fraction of the AD brain into the unilateral hippocampus. Results: After a long-term (17–19 months) post-injection, mice exhibited learning deficits detected by the Barnes maze test. Aggregated tau pathology in the bilateral hippocampus was more prominent in Tg601 mice than in NTg mice. No significant changes were observed in the number of Neu-N positive cells or astrocytes in the hippocampus, whereas that of Iba-I-positive microglia increased after the AD brain injection. Conclusion: These results potentially implicate tau propagation in functional decline and indicate that long-term changes in non-mutated tau mice may reflect human pathological conditions.

scholarly journals Disruption of the astrocyte–neuron interaction is responsible for the impairments in learning and memory in 5XFAD mice: an Alzheimer’s disease animal model

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Moonseok Choi ◽  
Sang-Min Lee ◽  
Dongsoo Kim ◽  
Heh-In Im ◽  
Hye-Sun Kim ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Animal Model ◽  
Memory Formation ◽  
Long Term Memory ◽  
Term Memory ◽  
Stat3 Phosphorylation ◽  
Neuron Interactions ◽  
5Xfad Mice

AbstractThe morphological dynamics of astrocytes are altered in the hippocampus during memory induction. Astrocyte–neuron interactions on synapses are called tripartite synapses. These control the synaptic function in the central nervous system. Astrocytes are activated in a reactive state by STAT3 phosphorylation in 5XFAD mice, an Alzheimer’s disease (AD) animal model. However, changes in astrocyte–neuron interactions in reactive or resting-state astrocytes during memory induction remain to be defined. Here, we investigated the time-dependent changes in astrocyte morphology and the number of astrocyte–neuron interactions in the hippocampus over the course of long-term memory formation in 5XFAD mice. Hippocampal-dependent long-term memory was induced using a contextual fear conditioning test in 5XFAD mice. The number of astrocytic processes increased in both wild-type and 5XFAD mice during memory formation. To assess astrocyte–neuron interactions in the hippocampal dentate gyrus, we counted the colocalization of glial fibrillary acidic protein and postsynaptic density protein 95 via immunofluorescence. Both groups revealed an increase in astrocyte–neuron interactions after memory induction. At 24 h after memory formation, the number of tripartite synapses returned to baseline levels in both groups. However, the total number of astrocyte–neuron interactions was significantly decreased in 5XFAD mice. Administration of Stattic, a STAT3 phosphorylation inhibitor, rescued the number of astrocyte–neuron interactions in 5XFAD mice. In conclusion, we suggest that a decreased number of astrocyte–neuron interactions may underlie memory impairment in the early stages of AD.

Lentivirus-Mediated Expression of Human Secreted Amyloid Precursor Protein-Alpha Promotes Long-Term Induction of Neuroprotective Genes and Pathways in a Mouse Model of Alzheimer’s Disease

2020 ◽  
pp. 1-16
Author(s):  
Margaret Ryan ◽  
Valerie T.Y. Tan ◽  
Nasya Thompson ◽  
Diane Guévremont ◽  
Bruce G. Mockett ◽  
...  
Keyword(s):  
Gene Expression ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Mouse Model ◽  
Amyloid Precursor Protein ◽  
Precursor Protein ◽  
Integrated Analysis ◽  
Empty Vector ◽  
Mouse Transcriptome

Background: Secreted amyloid precursor protein-alpha (sAPPα) can enhance memory and is neurotrophic and neuroprotective across a range of disease-associated insults, including amyloid-β toxicity. In a significant step toward validating sAPPα as a therapeutic for Alzheimer’s disease (AD), we demonstrated that long-term overexpression of human sAPPα (for 8 months) in a mouse model of amyloidosis (APP/PS1) could prevent the behavioral and electrophysiological deficits that develop in these mice. Objective: To explore the underlying molecular mechanisms responsible for the significant physiological and behavioral improvements observed in sAPPα-treated APP/PS1 mice. Methods: We assessed the long-term effects on the hippocampal transcriptome following continuous lentiviral delivery of sAPPα or empty-vector to male APP/PS1 mice and wild-type controls using Affymetrix Mouse Transcriptome Assays. Data analysis was carried out within the Affymetrix Transcriptome Analysis Console and an integrated analysis of the resulting transcriptomic data was performed with Ingenuity Pathway analysis (IPA). Results: Mouse transcriptome assays revealed expected AD-associated gene expression changes in empty-vector APP/PS1 mice, providing validation of the assays used for the analysis. By contrast, there were specific sAPPα-associated gene expression profiles which included increases in key neuroprotective genes such as Decorin, betaine-GABA transporter, and protocadherin beta-5, subsequently validated by qRT-PCR. An integrated biological pathways analysis highlighted regulation of GABA receptor signaling, cell survival, and inflammatory responses. Furthermore, upstream gene regulatory analysis implicated sAPPα activation of Interleukin-4, which can counteract inflammatory changes in AD. Conclusion: This study identified key molecular processes that likely underpin the long-term neuroprotective and therapeutic effects of increasing sAPPα levels in vivo

scholarly journals The individual course of neuropsychiatric symptoms in people with Alzheimer's and Lewy body dementia: 12-year longitudinal cohort study

2019 ◽  
Vol 216 (1) ◽  
pp. 43-48 ◽  
Author(s):  
Audun Osland Vik-Mo ◽  
Lasse Melvaer Giil ◽  
Miguel Germán Borda ◽  
Clive Ballard ◽  
Dag Aarsland
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Neuropsychiatric Symptoms ◽  
Personalised Medicine ◽  
Lewy Bodies ◽  
Lewy Body Dementia ◽  
Psychotic Symptoms ◽  
Primary Inclusion ◽  
The Individual

IntroductionUnderstanding the natural course of neuropsychiatric symptoms (NPS) in dementia is important for planning patient care and trial design, but few studies have described the long-term course of NPS in individuals.MethodPrimary inclusion of 223 patients with suspected mild dementia from general practice were followed by annual assessment, including the Neuropsychiatric Inventory (NPI), for up to 12 years. Total and item NPI scores were classified as stable, relapsing, single episodic or not present based on 4.96 (s.d. 2.3) observations (98% completeness of longitudinal data) for 113 patients with Alzheimer's disease and 84 patients with LBD (68 dementia with Lewy bodies and 16 Parkinson's disease dementia).ResultsWe found that 80% had stable NPI total ≥1, 50% had stable modest NPI total ≥12 and 25% had stable NPI total ≥24 scores. Very severe NPS (≥48) were mostly single episodes, but 8% of patients with Alzheimer's disease had stable severe NPS. Patients with Alzheimer's disease and the highest 20% NPI total scores had a more stable or relapsing course of four key symptoms: aberrant motor behaviour, aggression/agitation, delusions and irritability (odds ratio 55, P < 0.001). This was not seen in LBD. Finally, 57% of patients with Alzheimer's disease and 84% of patients with LBD had reoccurring psychotic symptoms.ConclusionsWe observed a highly individual course of NPS, with most presenting as a single episode or relapsing; a stable course was less common, especially in LBD. These findings demonstrate the importance of an individualised approach (i.e. personalised medicine) in dementia care.

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