The FDA-approved natural product dihydroergocristine reduces the production of the Alzheimer's disease amyloid-β peptides

Dihydroergotamine and Bromocriptine: Potential Drugs for the Treatment of Major Depressive Disorder and Alzheimer's Disease Comorbidity

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease that is characterized by memory loss and cognitive impairment. Evidence shows that depression is a common co-occurrence in AD patients, and major depressive disorder (MDD) is considered a risk factor for AD. The crosstalk between the biological procedures related to the two disorders makes it very difficult to treat the comorbid conditions caused by them. Considering the common pathophysiological mechanisms underlying AD and MDD, antidepressant drugs may have beneficial therapeutic effects against their concurrence. In this study, we aimed to explore the potential drug candidates for the prevention and treatment of the comorbidity of AD and MDD. First, we screened the potential drugs for treating MDD by evaluating the distances of drug targets to MDD-related genes on the human protein-protein interaction network (PPIN) via a network-based algorithm. Then, the drugs were further screened to identify those that may be effective for AD treatment by analyzing their affinities with tau protein and Aβ42 peptide via molecular docking. Furthermore, the most stable binding modes were identified via molecular dynamics simulations, and the regulatory effects of drug candidates on genes involved in the pathogenesis of AD and MDD were analyzed. A total of 506 MDD-related genes were retrieved, and 831 drug candidates for MDD treatment were screened via the network-based approach. The results from molecular docking and molecular dynamics simulations indicated dihydroergotamine had the lowest binding affinity with tau protein and bromocriptine could form the most stable binding mode with Aβ42 peptide. Further analyses found that both dihydroergotamine and bromocriptine could regulate the expression of genes involved in the pathogenesis of AD and/or MDD in the brain. The exact mechanisms of the two drugs in treating AD and MDD, as well as their comorbidity, are still unclear, and further exploration is needed to evaluate their roles and mechanisms, both in vitro and in vivo. This study revealed that dihydroergotamine and bromocriptine may be the potential drug candidates for the treatment of the comorbidity of AD and MDD, and the therapeutic effects may be achieved by inhibiting the accumulation and aggregation of Aβ42 and tau protein and regulating the expression of disease-related genes in the brain.

Untangling the complex mechanisms associated with Alzheimer's disease in elderly patients using high-throughput RNA sequencing data and next-generation knowledge discovery methods: Focus on potential gene signatures and drugs for dementia

Objectives

Alzheimer's disease (AD) is a complex neurodegenerative disorder that primarily affects elderly individuals. This study aimed to elucidate the intricate mechanisms underlying AD in elderly patients compared with healthy aged individuals using high-throughput RNA sequencing (RNA-seq) data and next-generation knowledge discovery methods (NGKD), with a focus on identifying potential therapeutic agents.

Methods

High-throughput RNA-seq data were obtained from the Gene Expression Omnibus (GEO) database (accession number: GSE104704). These data were derived from healthy and diseased human brains (eight young healthy brains [young], 10 aged healthy brains [Old], and 12 aged diseased brains [AD]). We used NGKD tools such as GEO RNA-seq Experiments Interactive Navigator (GREIN) to obtain differentially expressed genes (DEGs) by comparing the AD versus Old RNA-seq data and further filtered and normalized to obtain differentially regulated Kyoto Encyclopedia of Genes and Genomes (KEGG), Reactome and Panther pathways using ExpressAnalyst tool. Besides, WebGestalt was used to identify differentially regulated Gene Ontologies (GO) and the pre-ranked Gene Set Enrichment Analysis (GSEA) was performed using GSEA software. The X2K web tool was used to infer upstream regulator networks and X2K Appyter tool for obtaining transcription factors (TFs) and kinase network information. LFW1000 and L1000CDS2 tools were used to identify specific drugs that reverse AD-associated gene signatures in elderly patients.

Results

Our study revealed significant downregulation of pathways related to neuroactive receptor-ligand interaction, synaptic vesicle cycle, and neuronal system in elderly individuals with AD. GO analysis showed negative enrichment of functions related to cognition, potassium ion transport, receptor-ligand activity, SNARE binding, and primary lysosomes. The transcription factors SUZ12 and REST, along with increased MAPK signaling, were identified as key regulators of downregulated genes. Several drugs and natural products, including dihydroergocristine, mepacrine, gedunin, amlodipine, and disulfiram have been identified as potential therapeutic agents for reversing AD-associated gene signatures.

Conclusions

This comprehensive analysis of AD in elderly individuals using RNA-seq data and NGKD tools revealed multiple differentially regulated pathways, gene signatures, and potential drugs for dementia treatment. These findings highlight the complex molecular mechanisms underlying AD and provide insights into potential therapeutic strategies. Further research is needed to validate these findings and to develop personalized treatment approaches for AD in elderly patients.

DHEC mesylate attenuates pathologies and aberrant bisecting N-glycosylation in Alzheimer's disease models

Tremendous progress has been made to develop the therapy of Alzheimer's disease (AD). Existing several anti-AD remedies, with certain limitations, are far from adequate. Evidence suggests that dihydroergocristine (DHEC) mesylate, one of the main components of Ergoloid mesylates, can reduce the production of amyloid-β in vitro. However, the therapeutic effect of DHEC mesylate in AD and its underlying mechanism are still largely unknown. Herein, we characterized the pharmacological effect of DHEC mesylate in AD and found that the spatial memory disorders and Alzheimer-type pathologies were alleviated by DHEC mesylate administration. Moreover, we demonstrated that DHEC mesylate improved aberrant bisecting N-glycosylation, which was identified as a potential biomarker of AD. We further explored the underlying mechanism and confirmed that DHEC mesylate protected against AD via AMPK and ERK signaling, in which, AMPK was the dominant down-stream molecule of DHEC mesylate. In summary, our findings provide foundations for development of DHEC mesylate as a therapeutic approach for AD.

Review on anti-alzheimer drug development: approaches, challenges and perspectives

Alzheimer is an irreversible progressive neurodegenerative disease that causes failure of cerebral neurons and disability of the affected person to practice normal daily life activities. There is no concrete evidence to identify the exact reason behind the disease, so several relevant hypotheses emerged, highlighting many possible therapeutic targets, such as acetylcholinesterase, cholinergic receptors, N-methyl d-aspartate receptors, phosphodiesterase, amyloid β protein, protein phosphatase 2A, glycogen synthase kinase-3 beta, β-secretase, γ-secretase, α-secretase, serotonergic receptors, glutaminyl cyclase, tumor necrosis factor-α, γ-aminobutyric acid receptors, and mitochondria. All of these targets have been involved in the design of new potential drugs. An extensive number of these drugs have been studied in clinical trials. However, only galantamine, donepezil, and rivastigmine (ChEIs), memantine (NMDA antagonist), and aducanumab and lecanemab (selective anti-Aβ monoclonal antibodies) have been approved for AD treatment. Many drugs failed in the clinical trials to such an extent that questions have been posed about the significance of some of the aforementioned targets. On the contrary, the data of other drugs were promising and shed light on the significance of their targets for the development of new potent anti-alzheimer drugs.

Targeting aberrant glycosylation to modulate microglial response and improve cognition in models of Alzheimer's disease

Altered glycosylation profiles have been correlated with potential drug targets in various diseases, including Alzheimer's disease (AD). In this area, the linkage between bisecting N-acetylglucosamine (GlcNAc), a product of N-acetylglucosaminyltransferase III (GnT-III), and AD has been recognized, however, our understanding of the cause and the causative role of this aberrant glycosylation in AD are far from completion. Moreover, the effects and mechanisms of glycosylation-targeting interventions on memory and cognition, and novel targeting strategies are worth further study. Here, we showed the characteristic amyloid pathology-induced and age-related changes of GnT-III, and identified transcription factor 7-like 2 as the key transcription factor responsible for the abnormal expression of GnT-III in AD. Upregulation of GnT-III aggravated cognitive dysfunction and Alzheimer-like pathologies. In contrast, loss of GnT-III could improve cognition and alleviate pathologies. Furthermore, we found that an increase in bisecting GlcNAc modified ICAM-1 resulted in impairment of microglial responses, and genetic inactivation of GnT-III protected against AD mechanistically by blocking the aberrant glycosylation of ICAM-1 and subsequently modulating microglial responses, including microglial motility, phagocytosis ability, homeostatic/reactive state and neuroinflammation. Moreover, by target-based screening of GnT-III inhibitors from FDA-approved drug library, we identified two compounds, regorafenib and dihydroergocristine mesylate, showing pharmacological potential leading to modulation of aberrant glycosylation and microglial responses, and rescue of memory and cognition deficits.

Inhibition of γ-secretase/Notch pathway as a potential therapy for reversing cancer drug resistance

The mechanism of tumor drug resistance is complex and may involve stem cell maintenance, epithelial-mesenchymal transition, the activation of survival signaling pathways, transporter protein expression, and tumor microenvironment remodeling, all of which are linked to γ-secretase/Notch signaling. Increasing evidence has shown that the activation of the γ-secretase/Notch pathway is a key driver of cancer progression and drug resistance development and that γ-secretase inhibitors (GSIs) may be the most promising agents for reversing chemotherapy resistance of tumors by targeting the γ-secretase/Notch pathway. Here, we systematically summarize the roles in supporting γ-secretase/Notch activation-associated transformation of cancer cells into cancer stem cells, promotion of the EMT process, PI3K/Akt, MEK/ERK and NF-κB activation, enhancement of ABC transporter protein expression, and TME alteration in mediating tumor drug resistance. Subsequently, we analyze the mechanism of GSIs targeting the γ-secretase/Notch pathway to reverse tumor drug resistance and propose the outstanding advantages of GSIs in treating breast cancer drug resistance over other tumors. Finally, we emphasize that the development of GSIs for reversing tumor drug resistance is promising.

A Drug Repositioning Approach Reveals Ergotamine May Be a Potential Drug for the Treatment of Alzheimer's Disease

Background

Alzheimer's disease (AD) is a neurodegenerative disorder that is the most common form of dementia in the elderly. The drugs currently used to treat AD only have limited effects and are not able to cure the disease. Drug repositioning has increasingly become a promising approach to find potential drugs for diseases like AD.

Objective

To screen potential drug candidates for AD based on the relationship between risk genes of AD and drugs.

Methods

We collected the risk genes of AD and retrieved the information of known drugs from DrugBank. Then, the AD-related genes and the targets of each drug were mapped to the human protein-protein interaction network (PPIN) to represent AD and the drugs on the network. The network distances between each drug and AD were calculated to screen the drugs proximal to AD-related genes on PPIN, and the screened drug candidates were further analyzed by molecular docking and molecular dynamics simulations.

Results

We compiled a list of 714 genes associated with AD. From 5,833 drugs used for human diseases, we identified 1,044 drugs that could be potentially used to treat AD. Then, amyloid-β (Aβ) protein, the key molecule involved in the pathogenesis of AD was selected as the target to further screen drugs that may inhibit Aβ aggregation by molecular docking. We found that ergotamine and RAF-265 could bind stably with Aβ. In further analysis by molecular dynamics simulations, both drugs exhibited reasonable stability.

Conclusions

Our work indicated that ergotamine and RAF-265 may be potential candidates for treating AD.

Limosilactobacillus reuteri 29A Cell-Free Supernatant Antibiofilm and Antagonistic Effects in Murine Model of Vulvovaginal Candidiasis

Vaginal dysbiosis advocates burgeoning of devious human vaginal pathobionts like Candida species that possess multiple virulence properties and metabolic flexibility to cause infections. Inevitably, antifungal resistance may emerge due to their innate nature (e.g., biofilm formation), which assists in their virulence as well as the formation of persister cells after dispersal. In consequence, the phenomenon of biofilm involvement in vulvovaginal candidiasis (VVC) and its recurrence is becoming paramount. Lactic acid bacteria and their derivatives have proven to be hostile to Candida species. Here, we throw more light on the potency of the derivatives, i.e., cell-free supernatant (CFS) produced by an indigenously isolated vaginal Lactobacillus strain, Limosilactobacillus reuteri 29A. In the present study, we investigated the antibiofilm and antagonistic effects of L. reuteri 29A CFS, against biofilms of Candida species and in murine model of vulvovaginal candidiasis. In our in vitro biofilm study, the CFS disrupted and inhibited preformed biofilms of C. albicans and C. glabrata. Scanning electron microscopy displayed the destruction of preformed biofilms and impediment of C. albicans morphogenesis by the CFS. Gas chromatography-mass spectrometry analysis showed multiple key compounds that may act singly or synergistically. In vivo, the CFS showed no collateral damage to uninfected mice; the integrity of infected vaginal tissues was restored by the administration of the CFS as seen from the cytological, histopathological, and electron microscopical analyses. The results of this study document the potential use of CFS as an adjuvant or prophylactic option in addressing vaginal fungal infections.

Computer-assisted drug discovery of potential natural inhibitors of the SARS-CoV-2 RNA-dependent RNA polymerase through a multi-phase in silico approach

BACKGROUND

The COVID-19 pandemic has led to significant loss of life and economic disruption worldwide. Currently, there are limited effective treatments available for this disease. SARS-CoV-2 RNA-dependent RNA polymerase (SARS-CoV-2 RdRp) has been identified as a potential target for drug development against COVID-19. Natural products have been shown to possess antiviral properties, making them a promising source for developing drugs against SARS-CoV-2.

OBJECTIVES

The objective of this study is to identify the most effective natural inhibitors of SARS-CoV-2 RdRp among a set of 4924 African natural products using a multi-phase in silico approach.

METHODS

The study utilized remdesivir (RTP), the co-crystallized ligand of RdRp, as a starting point to select compounds that have the most similar chemical structures among the examined set of compounds. Molecular fingerprints and structure similarity studies were carried out in the first part of the study. The second part of the study included molecular docking against SARS-CoV-2 RdRp (PDB ID: 7BV2) and Molecular Dynamics (MD) simulations including the calculation of RMSD, RMSF, Rg, SASA, hydrogen bonding, and PLIP. Moreover, the calculations of Molecular mechanics with generalised Born and surface area solvation (MM-GBSA) Lennard-Jones and Columbic electrostatic interaction energies have been conducted. Additionally, in silico ADMET and toxicity studies were performed to examine the drug likeness degrees of the selected compounds.

RESULTS

Eight compounds were identified as the most effective natural inhibitors of SARS-CoV-2 RdRp. These compounds are kaempferol 3-galactoside, kaempferol 3-O-β-D-glucopyranoside, mangiferin methyl ether, luteolin 7-O-β-D-glucopyranoside, quercetin-O-β-D-3-glucopyranoside, 1-methoxy-3-indolylmethyl glucosinolate, naringenin, and asphodelin A 4'-O-β-D-glucopyranoside.

CONCLUSION

The results of this study provide valuable information for the development of natural product-based drugs against COVID-19. However, the elected compounds should be further studied in vitro and in vivo to confirm their efficacy in treating COVID-19.

Endothelial cells signaling and patterning under hypoxia: a mechanistic integrative computational model including the Notch-Dll4 pathway

Several signaling pathways are activated during hypoxia to promote angiogenesis, leading to endothelial cell patterning, interaction, and downstream signaling. Understanding the mechanistic signaling differences between normoxia and hypoxia can guide therapies to modulate angiogenesis. We present a novel mechanistic model of interacting endothelial cells, including the main pathways involved in angiogenesis. We calibrate and fit the model parameters based on well-established modeling techniques. Our results indicate that the main pathways involved in the patterning of tip and stalk endothelial cells under hypoxia differ, and the time under hypoxia affects how a reaction affects patterning. Interestingly, the interaction of receptors with Neuropilin1 is also relevant for cell patterning. Our simulations under different oxygen concentrations indicate time- and oxygen-availability-dependent responses for the two cells. Following simulations with various stimuli, our model suggests that factors such as period under hypoxia and oxygen availability must be considered for pattern control. This project provides insights into the signaling and patterning of endothelial cells under hypoxia, contributing to studies in the field.

Derivation of the multiply-branched ergot alkaloid pathway of fungi

Ergot alkaloids are a large family of fungal specialized metabolites that are important as toxins in agriculture and as the foundation of powerful pharmaceuticals. Fungi from several lineages and diverse ecological niches produce ergot alkaloids from at least one of several branches of the ergot alkaloid pathway. The biochemical and genetic bases for the different branches have been established and are summarized briefly herein. Several pathway branches overlap among fungal lineages and ecological niches, indicating activities of ergot alkaloids benefit fungi in different environments and conditions. Understanding the functions of the multiple genes in each branch of the pathway allows researchers to parse the abundant genomic sequence data available in public databases in order to assess the ergot alkaloid biosynthesis capacity of previously unexplored fungi. Moreover, the characterization of the genes involved in the various branches provides opportunities and resources for the biotechnological manipulation of ergot alkaloids for experimentation and pharmaceutical development.

Migraine Pharmacological Treatment and Cognitive Impairment: Risks and Benefits

Migraine is a common neurological disorder impairing the quality of life of patients. The condition requires, as an acute or prophylactic line of intervention, the frequent use of drugs acting on the central nervous system (CNS). The long-term impact of these medications on cognition and neurodegeneration has never been consistently assessed. The paper reviews pharmacological migraine treatments and discusses their biological and clinical effects on the CNS. The different anti-migraine drugs show distinct profiles concerning neurodegeneration and the risk of cognitive deficits. These features should be carefully evaluated when prescribing a pharmacological treatment as many migraineurs are of scholar or working age and their performances may be affected by drug misuse. Thus, a reconsideration of therapy guidelines is warranted. Furthermore, since conflicting results have emerged in the relationship between migraine and dementia, future studies must consider present and past pharmacological regimens as potential confounding factors.

Natural spirocyclic alkaloids and polyphenols as multi target dementia leads

The U rhynchophylla, U tomentosa, Isatis indigotica Fortune, Voacanga Africana, herbal constituents, fungal extracts from Aspergillus duricaulis culture media, include spirooxindoles, polyphenols or bridged spirocyclic alkaloids. Their constituents exhibit specific and synergistic multiple neuroprotective properties including inhibiting of Aβ fibril induced cytotoxicity, NMDA receptor inhibition in mice models of Alzheimer's disease (AD). The pioneering research from Woodward to Waldmann has advanced the synthesis of spirocyclic alkaloids. Furthermore, the elucidation of the genetic analysis, biochemical pathways that links strictosidine to the alkaloids akuammicine, stemmadenine, tabersonine, catharanthine, will now enable the biotechnological generation, also stimulate synthesis of related bridged spirocyclic alkaloids for medicinal investigations. From the value of spirocyclic structures as multi target dementia leads, we hypothesise that simpler Lipinski-like natural/synthetic alkaloid analogues may likewise be discovered that provide neurocognitive enhancing activities against dementia and AD.

Discovery of COVID-19 Inhibitors Targeting the SARS-CoV-2 Nsp13 Helicase

The raging COVID-19 pandemic caused by SARS-CoV-2 has infected tens of millions of people and killed several hundred thousand patients worldwide. Currently, there are no effective drugs or vaccines available for treating coronavirus infections. In this study, we have focused on the SARS-CoV-2 helicase (Nsp13), which is critical for viral replication and the most conserved nonstructural protein within the coronavirus family. Using homology modeling that couples published electron-density with molecular dynamics (MD)-based structural refinements, we generated structural models of the SARS-CoV-2 helicase in its apo- and ATP/RNA-bound conformations. We performed virtual screening of ∼970 000 chemical compounds against the ATP-binding site to identify potential inhibitors. Herein, we report docking hits of approved human drugs targeting the ATP-binding site. Importantly, two of our top drug hits have significant activity in inhibiting purified recombinant SARS-CoV-2 helicase, providing hope that these drugs can be potentially repurposed for the treatment of COVID-19.

Harnessing endophenotypes and network medicine for Alzheimer's drug repurposing

Following two decades of more than 400 clinical trials centered on the "one drug, one target, one disease" paradigm, there is still no effective disease-modifying therapy for Alzheimer's disease (AD). The inherent complexity of AD may challenge this reductionist strategy. Recent observations and advances in network medicine further indicate that AD likely shares common underlying mechanisms and intermediate pathophenotypes, or endophenotypes, with other diseases. In this review, we consider AD pathobiology, disease comorbidity, pleiotropy, and therapeutic development, and construct relevant endophenotype networks to guide future therapeutic development. Specifically, we discuss six main endophenotype hypotheses in AD: amyloidosis, tauopathy, neuroinflammation, mitochondrial dysfunction, vascular dysfunction, and lysosomal dysfunction. We further consider how this endophenotype network framework can provide advances in computational and experimental strategies for drug-repurposing and identification of new candidate therapeutic strategies for patients suffering from or at risk for AD. We highlight new opportunities for endophenotype-informed, drug discovery in AD, by exploiting multi-omics data. Integration of genomics, transcriptomics, radiomics, pharmacogenomics, and interactomics (protein-protein interactions) are essential for successful drug discovery. We describe experimental technologies for AD drug discovery including human induced pluripotent stem cells, transgenic mouse/rat models, and population-based retrospective case-control studies that may be integrated with multi-omics in a network medicine methodology. In summary, endophenotype-based network medicine methodologies will promote AD therapeutic development that will optimize the usefulness of available data and support deep phenotyping of the patient heterogeneity for personalized medicine in AD.

Discovery of COVID-19 Inhibitors Targeting the SARS-CoV2 Nsp13 Helicase

The raging COVID-19 pandemic caused by SARS-CoV2 has infected millions of people and killed several hundred thousand patients worldwide. Currently, there are no effective drugs or vaccines available for treating coronavirus infections. In this study, we have focused on the SARS-CoV2 helicase (Nsp13), which is critical for viral replication and the most conserved non-structural protein within the coronavirus family. Using homology modeling and molecular dynamics approaches, we generated structural models of the SARS-CoV2 helicase in its apo- and ATP/RNA-bound conformations. We performed virtual screening of ~970,000 chemical compounds against the ATP binding site to identify potential inhibitors. Herein, we report docking hits of approved human drugs targeting the ATP binding site. Importantly, two of our top drug hits have significant activity in inhibiting purified recombinant SARS-CoV-2 helicase, providing hope that these drugs can be potentially repurposed for the treatment of COVID-19.

Targeting Amyloidogenic Processing of APP in Alzheimer's Disease

Alzheimer's disease (AD) is the most common type of senile dementia, characterized by neurofibrillary tangle and amyloid plaque in brain pathology. Major efforts in AD drug were devoted to the interference with the production and accumulation of amyloid-β peptide (Aβ), which plays a causal role in the pathogenesis of AD. Aβ is generated from amyloid precursor protein (APP), by consecutive cleavage by β-secretase and γ-secretase. Therefore, β-secretase and γ-secretase inhibition have been the focus for AD drug discovery efforts for amyloid reduction. Here, we review β-secretase inhibitors and γ-secretase inhibitors/modulators, and their efficacies in clinical trials. In addition, we discussed the novel concept of specifically targeting the γ-secretase substrate APP. Targeting amyloidogenic processing of APP is still a fundamentally sound strategy to develop disease-modifying AD therapies and recent advance in γ-secretase/APP complex structure provides new opportunities in designing selective inhibitors/modulators for AD.

Aging Fits the Disease Criteria of the International Classification of Diseases

The disease criteria used by the World Health Organization (WHO) were applied to human biological aging in order to assess whether aging can be classified as a disease. These criteria were developed for the 11th revision of the International Classification of Diseases (ICD) and included disease diagnostics, mechanisms, course and outcomes, known interventions, and linkage to genetic and environmental factors. RESULTS: Biological aging can be diagnosed with frailty indices, functional, blood-based biomarkers. A number of major causal mechanisms of human aging involved in various organs have been described, such as inflammation, replicative cellular senescence, immune senescence, proteostasis failures, mitochondrial dysfunctions, fibrotic propensity, hormonal aging, body composition changes, etc. We identified a number of clinically proven interventions, as well as genetic and environmental factors of aging. Therefore, aging fits the ICD-11 criteria and can be considered a disease. Our proposal was submitted to the ICD-11 Joint Task force, and this led to the inclusion of the extension code for "Ageing-related" (XT9T) into the "Causality" section of the ICD-11. This might lead to greater focus on biological aging in global health policy and might provide for more opportunities for the new therapy developers.

The Use of Nutraceuticals to Counteract Atherosclerosis: The Role of the Notch Pathway

Despite the currently available pharmacotherapies, today, thirty percent of worldwide deaths are due to cardiovascular diseases (CVDs), whose primary cause is atherosclerosis, an inflammatory disorder characterized by the buildup of lipid deposits on the inside of arteries. Multiple cellular signaling pathways have been shown to be involved in the processes underlying atherosclerosis, and evidence has been accumulating for the crucial role of Notch receptors in regulating the functions of the diverse cell types involved in atherosclerosis onset and progression. Several classes of nutraceuticals have potential benefits for the prevention and treatment of atherosclerosis and CVDs, some of which could in part be due to their ability to modulate the Notch pathway. In this review, we summarize the current state of knowledge on the role of Notch in vascular health and its modulation by nutraceuticals for the prevention of atherosclerosis and/or treatment of related CVDs.

The Multiplicity of Polypeptide GalNAc-Transferase: Assays, Inhibitors, and Structures

Mucin-type O-glycosylation is the dominant form of glycosylation in eukaryotes and plays an important role in various physiological processes. The polypeptide GalNAc-transferase (GalNAc-T) catalyzes the first step in the attachment of mucin-type O-glycosylation. GalNAc-T was recently uncovered to be linked with cancer, atherogenic dyslipidemia, and X-linked hypophosphatemic rickets. Therefore, it has attracted increasing interest as a new target for exploring the underlying mechanism and developing new treatments for related diseases. Decades of studies on GalNAc-T have laid a stable foundation for understanding the catalytic mechanism, determining atom-resolution three-dimensional structures, and developing various types of biochemical assays as well as small-molecule inhibitor leads. Here, we systematically summarize this invaluable knowledge on GalNAc-T and cultivate new perspectives to foster breakthrough points for mucin-type O-glycosylation.

Ergot Alkaloid Synthesis Capacity of Penicillium camemberti

Ergot alkaloids are specialized fungal metabolites with potent biological activities. They are encoded by well-characterized gene clusters in the genomes of producing fungi. Penicillium camemberti plays a major role in the ripening of Brie and Camembert cheeses. The P. camemberti genome contains a cluster of five genes shown in other fungi to be required for synthesis of the important ergot alkaloid intermediate chanoclavine-I aldehyde and two additional genes (easH and easQ) that may control modification of chanoclavine-I aldehyde into other ergot alkaloids. We analyzed samples of Brie and Camembert cheeses, as well as cultures of P. camemberti, and did not detect chanoclavine-I aldehyde or its derivatives. To create a functioning facsimile of the P. camembertieas cluster, we expressed P. camemberti easH and easQ in a chanoclavine-I aldehyde-accumulating easA knockout mutant of Neosartorya fumigata The easH-easQ-engineered N. fumigata strain accumulated a pair of compounds of m/z 269.1288 in positive-mode liquid chromatography-mass spectrometry (LC-MS). The analytes fragmented in a manner typical of the stereoisomeric ergot alkaloids rugulovasine A and B, and the related rugulovasine producer Penicillium biforme accumulated the same isomeric pair of analytes. The P. camemberti eas genes were transcribed in culture, but comparison of the P. camemberti eas cluster with the functional cluster from P. biforme indicated 11 polymorphisms. Whereas other P. camembertieas genes functioned when expressed in N. fumigata, P. camembertieasC did not restore ergot alkaloids when expressed in an easC mutant. The data indicate that P. camemberti formerly had the capacity to produce the ergot alkaloids rugulovasine A and B.IMPORTANCE The presence of ergot alkaloid synthesis genes in the genome of Penicillium camemberti is significant, because the fungus is widely consumed in Brie and Camembert cheeses. Our results show that, although the fungus has several functional genes from the ergot alkaloid pathway, it produces only an early pathway intermediate in culture and does not produce ergot alkaloids in cheese. Penicillium biforme, a close relative of P. camemberti, contains a similar but fully functional set of ergot alkaloid synthesis genes and produces ergot alkaloids chanoclavine-I, chanoclavine-I aldehyde, and rugulovasine A and B. Our reconstruction of the P. camemberti pathway in the model fungus Neosartorya fumigata indicated that P. camemberti formerly had the capacity to produce these same ergot alkaloids. Neither P. camemberti nor P. biforme produced ergot alkaloids in cheese, indicating that nutritionally driven gene regulation prevents these fungi from producing ergot alkaloids in a dairy environment.

Have there been improvements in Alzheimer's disease drug discovery over the past 5 years?

INTRODUCTION

Alzheimer's disease (AD) is the most important neurodegenerative disorder with a global cost worldwide of over $700 billion. Pharmacological treatment accounts for 10-20% of direct costs; no new drugs have been approved during the past 15 years; and the available medications are not cost-effective. Areas covered: A massive scrutiny of AD-related PubMed publications (ps)(2013-2017) identified 42,053ps of which 8,380 (19.60%) were associated with AD treatments. The most prevalent pharmacological categories included neurotransmitter enhancers (11.38%), multi-target drugs (2.45%), anti-Amyloid agents (13.30%), anti-Tau agents (2.03%), natural products and derivatives (25.58%), novel drugs (8.13%), novel targets (5.66%), other (old) drugs (11.77%), anti-inflammatory drugs (1.20%), neuroprotective peptides (1.25%), stem cell therapy (1.85%), nanocarriers/nanotherapeutics (1.52%), and others (<1% each). Expert opinion: Unsuccessful outcomes in AD therapeutics are attributed to pathogenic misconceptions, erratic procedures in drug development and inappropriate regulations. Recommendations for the future are as follows: (i) the reconsideration of dominant pathogenic theories, (ii) the identification of reliable biomarkers, (iii) the redefinition of diagnostic criteria, (iv) new guidelines for disease management, (v) the reorientation of drug discovery programs, (vi) the updating of regulatory requirements, (vii) the introduction of pharmacogenomics in drug development and personalized treatments, and (viii) the implementation of preventive programs.

Amyloid beta modulators and neuroprotection in Alzheimer's disease: a critical appraisal

Multiple cellular changes have been identified as being involved in Alzheimer's disease (AD) pathogenesis, including mitochondrial damage, synaptic loss, amyloid beta (Aβ) production and/or accumulation, inflammatory responses, and phosphorylated tau formation and/or accumulation. Studies have established that Aβ-induced synaptic dysfunction is dependent on abnormal amyloid precursor protein (APP) processing caused by β- and γ-secretases, resulting in the generation of Aβ. The Aβ formed as a result of abnormal APP processing induces phosphorylated tau and activates glycogen synthase kinase-3β (GSK3β) and cyclin-dependent kinase-5 (CDK5). Here, we review the latest research on the development of Aβ modulators for neuroprotection in AD. We also review the use of molecular inhibitors as therapeutic targets in AD.