Shaping the future of antiviral Treatment: Spotlight on Nucleobase-Containing drugs and their revolutionary impact.

Nucleobases serve as essential molecular frameworks present in both natural and synthetic compounds that exhibit notable antiviral activity. Through molecular modifications, novel nucleobase-containing drugs (NCDs) have been developed, exhibiting enhanced antiviral activity against a wide range of viruses, including the recently emerged SARS­CoV­2. This article provides a detailed examination of the significant advancements in NCDs from 2015 till current, encompassing various aspects concerning their mechanisms of action, pharmacology and antiviral properties. Additionally, the article discusses antiviral prodrugs relevant to the scope of this review. It fills in the knowledge gap by examining the structure-activity relationship and trend of NCDs as therapeutics against a diverse range of viral diseases, either as approved drugs, clinical candidates or as early-stage development prospects. Moreover, the article highlights on the status of this field of study and addresses the prevailing limitations encountered.

Anti-Amyloid ß Aggregation Activity and Cell Viability Effect of Betacyanins from Red Pitahaya (Hylocereus polyrhizus) for Alzheimer's Disease.

Betacyanin-rich extract from red beet (Beta vulgaris) was recently reported to inhibit amyloid ß (Aß) aggregation, a main pathological event in Alzheimer's disease. However, the anti-Aß aggregation effect of individual betacyanin isolates has not been reported before. This study investigated the anti-Aß aggregation activity and cytotoxicity of betacyanins from red pitahaya or red dragon fruit (Hylocereus polyrhizus). Betacyanin fraction (IC50 = 16.02 ± 1.15 µg/mL) and individual betacyanin isolates exhibited anti-Aß aggregation activity in a concentration-dependent manner using a thioflavin T fluorescence assay. The highest to lowest IC50 was in the order of betanin (426.30 ± 29.55 µM), phyllocactin (175.22 ± 1.52 µM), and hylocerenin (131.73 ± 5.58 µM), following a trend of increase in functional groups of carboxyl, hydroxyl, and/or carbonyl. Further, the betacyanin fraction of 135.78 µg/mL and below, which were concentrations with an anti-Aß aggregation effect, were validated as non-neurotoxic based on an in vitro cytotoxicity assay using human neuroblastoma (SH-SY5Y) cells. These findings highlight the potential neuroprotective activity of betacyanins for Alzheimer's disease.

The Role of Interferon-α in Neurodegenerative Diseases: A Systematic Review.

BACKGROUND: Neurodegenerative diseases (NDs) impose significant financial and healthcare burden on populations all over the world. The prevalence and incidence of NDs have been observed to increase dramatically with age. Hence, the number of reported cases is projected to increase in the future, as life spans continues to rise. Despite this, there is limited effective treatment against most NDs. Interferons (IFNs), a family of cytokines, have been suggested as a promising therapeutic target for NDs, particularly IFN-α, which governs various pathological pathways in different NDs. OBJECTIVE: This systematic review aimed to critically appraise the currently available literature on the pathological role of IFN-α in neurodegeneration/NDs. METHODS: Three databases, Scopus, PubMed, and Ovid Medline, were utilized for the literature search. RESULTS: A total of 77 journal articles were selected for critical evaluation, based on the inclusion and exclusion criteria. The studies selected and elucidated in this current systematic review have showed that IFN-α may play a deleterious role in neurodegenerative diseases through its strong association with the inflammatory processes resulting in mainly neurocognitive impairments. IFN-α may be displaying its neurotoxic function via various mechanisms such as abnormal calcium mineralization, activation of STAT1-dependent mechanisms, and increased quinolinic acid production. CONCLUSION: The exact role IFN-α in these neurodegenerative diseases have yet to be determine due to a lack in more recent evidence, thereby creating a variability in the role of IFN-α. Future investigations should thus be conducted, so that the role played by IFN-α in neurodegenerative diseases could be delineated.

Linking Diabetes to Alzheimer's Disease: Potential Roles of Glucose Metabolism and Alpha-Glucosidase.

Alzheimer's disease (AD) and type 2 diabetes mellitus (DM) are more prevalent with ageing and cause a substantial global socio-economic burden. The biology of these two conditions is well elaborated, but whether AD and type 2 DM arise from coincidental roots in ageing or are linked by pathophysiological mechanisms remains unclear. Research findings involving animal models have identified mechanisms shared by both AD and type 2 DM. Deposition of ß-amyloid peptides and formation of intracellular neurofibrillary tangles are pathological hallmarks of AD. Type 2 DM, on the other hand, is a metabolic disorder characterised by hyperglycaemia and insulin resistance. Several studies show that improving type 2 DM can delay or prevent the development of AD, and hence, prevention and control of type 2 DM may reduce the risk of AD later in life. Alpha-glucosidase is an enzyme that is commonly associated with hyperglycaemia in type 2 DM. However, it is uncertain if this enzyme may play a role in the progression of AD. This review explores the experimental evidence that depicts the relationship between dysregulation of glucose metabolism and AD. We also delineate the links between alpha-glucosidase and AD and the potential role of alpha-glucosidase inhibitors in treating AD.

Synthesis of novel carboxamide- and carbohydrazide-benzimidazoles as selective butyrylcholinesterase inhibitors.

Selectively inhibiting butyrylcholinesterase (BChE) is hypothesized to help in the management of Alzheimer's disease (AD). Several studies have determined a correlation between the increased activity of BChE and the onset of AD. An advantage of BChE over acetylcholinesterase inhibition is that absence of BChE activity does not lead to obvious physiological disturbance. However, currently no BChE inhibitors are available commercially as potential therapeutics for AD. In our continuous effort to find potent BChE inhibitors for Alzheimer's disease, a total of 22 novel benzimidazoles with diversified substitutions were synthesized and evaluated for their anticholinesterase activities in this study. Among the synthesized compounds, 2j and 3f were found to exhibit potent and selective BChE inhibition with IC50 values of 1.13 and 1.46 µM, respectively. Molecular docking studies were carried out to rationalize the observed inhibitory activities. The compounds were predicted to have high penetration across the blood-brain barrier. Moreover, cell proliferative studies were also performed to evaluate the toxicity profile of the interested compounds. Compound 3f was found to be a potent and selective butyrylcholinesterase inhibitor with an IC50 value of 1.46 µM.

Modern vaccine development via reverse vaccinology to combat antimicrobial resistance.

With the continuous evolution of bacteria, the global antimicrobial resistance health threat is causing millions of deaths yearly. While depending on antibiotics as a primary treatment has its merits, there are no effective alternatives thus far in the pharmaceutical market against some drug-resistant bacteria. In recent years, vaccinology has become a key topic in scientific research. Combining with the growth of technology, vaccine research is seeing a new light where the process is made faster and more efficient. Although less discussed, bacterial vaccine is a feasible strategy to combat antimicrobial resistance. Some vaccines have shown promising results with good efficacy against numerous multidrug-resistant strains of bacteria. In this review, we aim to discuss the findings from studies utilizing reverse vaccinology for vaccine development against some multidrug-resistant bacteria, as well as provide a summary of multi-year bacterial vaccine studies in clinical trials. The advantages of reverse vaccinology in the generation of new bacterial vaccines are also highlighted. Meanwhile, the limitations and future prospects of bacterial vaccine concludes this review.

Current trends of benzothiazoles in drug discovery: a patent review (2015-2020).

INTRODUCTION: Benzothiazole is a bicyclic ring system composed of thiazole and benzene rings. It is present as an important pharmacophore in many marketed drugs. The notable potential of benzothiazoles as therapeutic agent for different target diseases has prompted a growing interest in benzothiazole-based drug development in recent years. AREAS COVERED: This review of 55 benzothiazole-related patents, filed from 2015 to 2020, covers a wide range of pharmacological activities. These patents were collated from Google Patents and Lens search engines. The inventions were categorized and discussed based on their respective group of target diseases, including metabolic diseases, cancer, inflammation, neurodegeneration, viral diseases, bacterial infections, fibrosis and thrombosis. EXPERT OPINION: Benzothiazole has shown to be a scaffold with great pharmacological importance and thus, serves as a building block for the development of derivatives having high therapeutic activity. Benzothiazole derivatives were patented for a range of therapeutic applications, with a special focus on cancer research. Several compounds have the potential to progress into the market, given that they exert both selectivity and in vivo efficacy. Others require a more thorough study to obtain adequate information on the compounds.

Potential Roles of α-amylase in Alzheimer's Disease: Biomarker and Drug Target.

Alzheimer's disease (AD), the most common form of dementia, is pathologically characterized by the deposition of amyloid-ß plaques and the formation of neurofibrillary tangles. In a neurodegenerative brain, glucose metabolism is also impaired and considered as one of the key features in AD patients. The impairment causes a reduction in glucose transporters and the uptake of glucose as well as alterations in the specific activity of glycolytic enzymes. Recently, it has been reported that α-amylase, a polysaccharide-degrading enzyme, is present in the human brain. The enzyme is known to be associated with various diseases such as type 2 diabetes mellitus and hyperamylasaemia. With this information at hand, we hypothesize that α-amylase could have a vital role in the demented brains of AD patients. This review aims to shed insight into the possible link between the expression levels of α-amylase and AD. Lastly, we also cover the diverse role of amylase inhibitors and how they could serve as a therapeutic agent to manage or stop AD progression.

A rhodamine based chemosensor for solvent dependent chromogenic sensing of cobalt (II) and copper (II) ions with good selectivity and sensitivity: Synthesis, filter paper test strip, DFT calculations and cytotoxicity.

A new chemosensor 1 was synthesized by reacting rhodamine B hydrazide and 2,3,4-trihydroxybenzaldehyde, which was then characterized by spectroscopic techniques and single crystal X-ray crystallography. Sensor 1 has the ability to sense Co2+/Cu2+ ions by "naked-eye" with an apparent colour change from colourless to pink in different solvent system, MeCN and DMF respectively. Furthermore, it can selectively detect Co2+/Cu2+ among wide range of different metal ions, and it exhibits low detection limit of 4.425 × 10-8 M and 1.398 × 10-7 M respectively. Binding mode of the two complexes were determined to be 1:1 stoichiometry for Co2+ complex and 1:2 stoichiometry for Cu2+ complex through Job's plot, IR spectroscopy, mass spectrometry and 1H NMR spectroscopy. Moreover, reversibility of the sensor 1 as copper (II) ion detector was determined by using EDTA and the results showed that sensor 1 can be reused for at least 6 cycles. Other than that, a low cost chemosensor test strips were fabricated for the convenient "naked-eye" detection of Co2+ and Cu2+ in pure aqueous media. The MTT assay was conducted in order to determine the cytotoxicity of sensor 1 towards human cell lines.

A Patent Review on the Current Developments of Benzoxazoles in Drug Discovery.

The benzoxazole moiety is widely found in various natural compounds, which are often found to be biologically active. Due to its versatile biological properties, benzoxazole has been incorporated as an essential pharmacophore and substructure in many medicinal compounds. In the past years, numerous benzoxazole derivatives have been synthesised and evaluated for their biological potential. The wide range in therapeutic potential of benzoxazole derivatives is related to the favourable interactions of the benzoxazole moiety with different protein targets. Herein we review the biological activities of benzoxazole derivatives patented within the past six years. Using the Lens database, granted patents issued from 2015 to 2020 were retrieved. The patented benzoxazole derivatives demonstrated excellent activity against various protein targets and diseases, with some reaching clinical trial stage. Pharmacological and medicinal aspects of patented benzoxazole derivatives are discussed. The recent development and drawbacks are also reviewed.

Monitoring of heavy metal pollution in urban and rural environments across Pakistan using House crows (Corvus splendens) as bioindicator.

A widely distributed urban bird, the house crow (Corvus splendens), was used to assess bioavailable heavy metals in urban and rural environments across Pakistan. Bioaccumulation of arsenic (As), zinc (Zn), lead (Pb), cadmium (Cd), nickel (Ni), iron (Fe), manganese (Mn), chromium (Cr), and copper (Cu) was investigated in wing feathers of 96 crows collected from eight locations and categorized into four groups pertaining to their geographical and environmental similarities. Results revealed that the concentrations of Pb, Ni, Mn, Cu, and Cr were positively correlated and varied significantly among the four groups. Zn, Fe, Cr, and Cu regarded as industrial outputs, were observed in birds both in industrialized cities and in adjoining rural agricultural areas irrigated through the Indus Basin Irrigation System. Birds in both urban regions accrued Pb more than the metal toxicity thresholds for birds. The house crow was ranked in the middle on the metal accumulation levels in feathers between highly accumulating raptor and piscivore and less contaminated insectivore and granivore species in the studied areas,. This study suggests that the house crow is an efficient bioindicator and supports the feasibility of using feathers to discriminate the local pollution differences among terrestrial environments having different levels and kinds of anthropogenic activities.

Natural Sirtuin Modulators in Drug Discovery: A Review (2010 -2020).

There have been intense research interests in sirtuins since the establishment of their regulatory roles in a myriad of pathological processes. In the last two decades, many research efforts have been dedicated to the development of sirtuin modulators. Although synthetic sirtuin modulators are the focus, natural modulators remain an integral part to be further explored in this area as they are found to possess therapeutic potential in various diseases, including cancers, neurodegenerative diseases, and metabolic disorders. Owing to the importance of this cluster of compounds, this review gives a current stand on the naturally occurring sirtuin modulators, associated molecular mechanisms, and their therapeutic benefits. Furthermore, comprehensive data mining resulted in detailed statistical data analysis pertaining to the developmental trend of sirtuin modulators from 2010-2020. Lastly, the challenges and future prospects of natural sirtuin modulators in drug discovery will also be discussed.

From Nucleic Acids to Drug Discovery: Nucleobases as Emerging Templates for Drug Candidates.

Nucleobases represent key structural motifs in biologically active molecules, including synthetic and natural products. Molecular modifications made on nucleobases or their isolation from natural sources are being widely investigated for the development of drugs with improved potency for the treatment of different diseases, such as cancer, as well as viral and bacterial infections. This review article focuses on the nucleobase analogue drug developments of the past 20 years (2000-2020). Various pharmacological and medicinal aspects of nucleobases and their analogues are discussed. The current state and limitations are also highlighted.

Repurposing Antihypertensive Drugs for the Management of Alzheimer's Disease.

Alzheimer's disease (AD) is a neurodegenerative disorder that has affected millions of people worldwide. However, currently, there is no treatment to cure the disease. The AD drugs available in the market only manage the disease symptomatically and the effects are usually short-term. Thus, there is a need to look at alternatives AD therapies. This literature review aims to shed some light on the potential of repurposing antihypertensives to treat AD. Mid-life hypertension has not only been recognised as a risk factor for AD, but its relation with AD has also been well established. Hence, antihypertensives were postulated to be beneficial in managing AD. Four classes of antihypertensives, as well as their potential limitations and prospects in being utilised as AD therapeutics, were discussed in this review.

Sirtuins and Their Implications in Neurodegenerative Diseases from a Drug Discovery Perspective.

Sirtuins are class III histone deacetylase (HDAC) enzymes that target both histone and non-histone substrates. They are linked to different brain functions and the regulation of different isoforms of these enzymes is touted to be an emerging therapy for the treatment of neurodegenerative diseases (NDs), including Parkinson's disease (PD), Alzheimer's disease (AD), and amyotrophic lateral sclerosis (ALS). The level of sirtuins affects brain health as many sirtuin-regulated pathways are responsible for the progression of NDs. Certain sirtuins are also implicated in aging, which is a risk factor for many NDs. In addition to SIRT1-3, it has been suggested that the less studied sirtuins (SIRT4-7) also play critical roles in brain health. This review delineates the role of each sirtuin isoform in NDs from a disease centric perspective and provides an up-to-date overview of sirtuin modulators and their potential use as therapeutics in these diseases. Furthermore, the future perspectives for sirtuin modulator development and their therapeutic application in neurodegeneration are outlined in detail, hence providing a research direction for future studies.

Scopolamine, a Toxin-Induced Experimental Model, Used for Research in Alzheimer's Disease.

Scopolamine as a drug is often used to treat motion sickness. Derivatives of scopolamine have also found applications as antispasmodic drugs among others. In neuroscience-related research, it is often used to induce cognitive disorders in experimental models as it readily permeates the bloodbrain barrier. In the context of Alzheimer's disease, its effects include causing cholinergic dysfunction and increasing amyloid-ß deposition, both of which are hallmarks of the disease. Hence, the application of scopolamine in Alzheimer's disease research is proven pivotal but seldom discussed. In this review, the relationship between scopolamine and Alzheimer's disease will be delineated through an overall effect of scopolamine administration and its specific mechanisms of action, discussing mainly its influences on cholinergic function and amyloid cascade. The validity of scopolamine as a model of cognitive impairment or neurotoxin model will also be discussed in terms of advantages and limitations with future insights.

Butyrylcholinesterase: A Multifaceted Pharmacological Target and Tool.

Butyrylcholinesterase is a serine hydrolase that catalyzes the hydrolysis of esters in the body. Unlike its sister enzyme acetylcholinesterase, butyrylcholinesterase has a broad substrate scope and lower acetylcholine catalytic efficiency. The difference in tissue distribution and inhibitor sensitivity also points to its involvement external to cholinergic neurotransmission. Initial studies on butyrylcholinesterase showed that the inhibition of the enzyme led to the increment of brain acetylcholine levels. Further gene knockout studies suggested its involvement in the regulation of amyloid-beta, a brain pathogenic protein. Thus, it is an interesting target for neurological disorders such as Alzheimer's disease. The substrate scope of butyrylcholinesterase was recently found to include cocaine, as well as ghrelin, the "hunger hormone". These findings led to the development of recombinant butyrylcholinesterase mutants and viral gene therapy to combat cocaine addiction, along with in-depth studies on the significance of butyrylcholinesterase in obesity. It is observed that the pharmacological impact of butyrylcholinesterase increased in tandem with each reported finding. Not only is the enzyme now considered an important pharmacological target, it is also becoming an important tool to study the biological pathways in various diseases. Here, we review and summarize the biochemical properties of butyrylcholinesterase and its roles, as a cholinergic neurotransmitter, in various diseases, particularly neurodegenerative disorders.

Discovery of gamma-mangostin from Garcinia mangostana as a potent and selective natural SIRT2 inhibitor.

Studies have suggested that sirtuin inhibition may have beneficial effects on several age-related diseases such as neurodegenerative disorders and cancer. Garcinia mangostana is a well-known tropical plant found mostly in South East Asia with several positive health effects. Some of its phytochemicals such as α-mangostin was found to be able to modulate sirtuin activity in mice and was implicated with inflammation, diabetes and obesity. However, comprehensive studies on sirtuin activity by the prenylated xanthones extracted from Garcinia mangostana have yet to be reported. The present study led to the discovery and identification of γ-mangostin as a potent and selective SIRT2 inhibitor. It was demonstrated that γ-mangostin was able to increase the α-tubulin acetylation in MDA-MD-231 and MCF-7 breast cancer cells. It was also found to possess potent antiproliferative activity against both cell lines. In addition, it was able to induce neurite outgrowth in the N2a cells.

Anticancer activities of a benzimidazole compound through sirtuin inhibition in colorectal cancer.

AIM: This study aims to investigate the mode of action of a novel sirtuin inhibitor (BZD9L1) and its associated molecular pathways in colorectal cancer (CRC) cells. MATERIALS & METHODS: BZD9L1 was tested against metastatic CRC cell lines to evaluate cytotoxicity, cell cycle and apoptosis, senescence, apoptosis related genes and protein expressions, as well as effect against major cancer signaling pathways. RESULTS & CONCLUSION: BZD9L1 reduced the viability, cell migration and colony forming ability of both HCT 116 and HT-29 metastatic CRC cell lines through apoptosis. BZD9L1 regulated major cancer pathways differently in CRC with different mutation profiles. BZD9L1 exhibited anticancer activities as a cytotoxic drug in CRC and as a promising therapeutic strategy in CRC treatment.

In silico studies, synthesis and pharmacological evaluation to explore multi-targeted approach for imidazole analogues as potential cholinesterase inhibitors with neuroprotective role for Alzheimer's disease.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder with multiple factors associated with its pathogenesis. Our strategy against AD involves design of multi-targeted 2-substituted-4,5-diphenyl-1H-imidazole analogues which can interact and inhibit AChE, thereby, increasing the synaptic availability of ACh, inhibit BuChE, relieve induced oxidative stress and confer a neuroprotective role. Molecular docking was employed to study interactions within the AChE active site. In silico ADME study was performed to estimate pharmacokinetic parameters. Based on computational studies, some analogues were synthesized and subjected to pharmacological evaluation involving antioxidant activity, toxicity and memory model studies in animals followed by detailed mechanistic in vitro cholinesterase inhibition study. Amongst the series, analogue 13 and 20 are the most promising multi-targeted candidates which can potentially increase memory, decrease free radical levels and protect neurons against cognitive deficit.