A highly selective and sensitive fluorescence assay for kanamycin has been developed that depends on complementation of two splits of DNA aptamer. One DNA split was labeled with CuS nanoparticle and ...the other was decorated with biotin, which enabled coupling with streptavidin magnesphere paramagnetic particles (PMPs). Complementation of the two-aptamer splits happened only in the presence of kanamycin and the subsequent sandwich was separated via a magnet. The released Cu(II) was reduced to Cu(I) by sodium ascorbate and finally catalyzed the click reaction between fluorogenic 3-azido-7-hydroxycoumarin and propargyl alcohol to afford the corresponding fluorescent 1,4-disubstituted-1,2,3-triazole. The fluorescence signal produced (λex. = 365 nm, λem. = 470 nm) was dependent on kanamycin concentration. Fluorescence signal amplification was found to be in good linear relationship with the logarithm of kanamycin concentration in the range of 0.04–20 nM. Furthermore, the proposed assay showed a good reproducibility, high selectivity and low detection limits for kanamycin determination. In addition, the capability of the proposed method to detect kanamycin in biological samples with satisfactory results was demonstrated.
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•Complementation of DNA aptamer splits and CuAAC click reaction were combined to detect kanamycin in Fluorescence assay.•Increase in fluorescence intensity was in linear correlation with the logarithm of concentrations in range of 0.04–20 nM.•Detection limit (LOD, 3σ) was as low as 26 pM.•The proposed method was selective and sensitive.
Emerging evidence supports an intertwining framework for the involvement of different inflammatory pathways in a common pathological background for a number of disorders. Of importance are pathways ...involving arachidonic acid metabolism by cyclooxygenase-2 (COX-2) and 15-lipoxygenase (15-LOX). Both enzyme activities and their products are implicated in a range of pathophysiological processes encompassing metabolic impairment leading to adipose inflammation and the subsequent vascular and neurological disorders, in addition to various pro- and antitumorigenic effects. A further layer of complexity is encountered by the disparate, and often reciprocal, modulatory effect COX-2 and 15-LOX activities and metabolites exert on each other or on other cellular targets, the most prominent of which is peroxisome proliferator-activated receptor gamma (PPARγ). Thus, effective therapeutic intervention with such multifaceted disorders requires the simultaneous modulation of more than one target. Here, we describe the role of COX-2, 15-LOX, and PPARγ in cancer and complications of metabolic disorders, highlight the value of designing multi-target directed ligands (MTDLs) modifying their activity, and summarizing the available literature regarding the rationale and feasibility of design and synthesis of these ligands together with their known biological effects. We speculate on the potential impact of MTDLs in these disorders as well as emphasize the need for structured future effort to translate these early results facilitating the adoption of these, and similar, molecules in clinical research.
Neuroinflammation and cholinergic deficit are key detrimental processes involved in Alzheimer's disease. Hence, in the search for novel and effective treatment strategies, the multi-target-directed ...ligand paradigm was applied to the rational design of two series of new hybrids endowed with anti-inflammatory and anticholinesterase activity via triple targeting properties, namely able to simultaneously hit cholinesterases, cyclooxygenase-2 (COX-2) and 15-lipoxygenase (15-LOX) enzymes. Among the synthesized compounds, triazoles 5b and 5d, and thiosemicarbazide hybrid 6e emerged as promising new hits, being able to effectively inhibit human butyrylcholinesterase (hBChE), COX-2 and 15-LOX enzymes with a higher inhibitory potency than the reference inhibitors tacrine (for hBChE inhibition), celecoxib (for COX-2 inhibition) and both NDGA and Zileuton (for 15-LOX inhibition). In addition, compound 6e proved to be a submicromolar mixed-type inhibitor of human acetylcholinesterase (hAChE). The anti-neuroinflammatory activity of the three most promising hybrids was confirmed in a cell-based assay using PC12 neuron cells, showing decreased expression levels of inflammatory cytokines IL-1β and TNF-α. Importantly, despite the structural resemblance to tacrine, they showed ideal safety profiles on hepatic and murine brain cell lines and were safe up to 100 μM when assayed in PC12 cells. All three hybrids were also predicted to have superior BBB permeability than tacrine in the PAMPA assay, and good physicochemical properties, drug-likeness and ligand efficiency indices. Finally, molecular docking studies highlighted key structural elements impacting selectivity and activity toward the selected target enzymes.
To the best of our knowledge, compounds 5b, 5d and 6e are the first balanced, safe and multi-target compounds hitting the disease at the three mentioned hubs.
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•Tetrahydroacridine-triazole and thiosemicarbazide hybrids were synthesized to serve as multi-target directed ligands for Alzheimer’s disease treatment.•Thiosemicarbazide derivative 6e inhibited hAChE, hBChE, COX-2 and 15-LOX enzymes at micromolar concentrations.•Triazoles 5b and 5d selectively inhibited hBChE as well as COX-2 and 15-LOX.•They decreased expression levels of inflammatory cytokines IL-1β and TNF-α in neuron cell-based assay.•These compounds were safe on both hepatic and neuronal cell lines.
In this work, the binding mechanism between donepezil (DNP) and bovine serum albumin (BSA) was established using several techniques, including fluorimetry, UV- spectrophotometry, synchronous ...fluorimetry (SF), fourier transform infrared (FTIR), fluorescence resonance energy transfer (FRET) besides molecular docking study. The fluorescence quenching mechanism of DNP-BSA binding was a combined dynamic and static quenching. The thermodynamic parameters, binding forces, binding constant, and the number of binding sites were determined using a different range of temperature settings. Van't Hoff's equation was used to calculate the reaction parameters, including enthalpy change (ΔH
ο
) and entropy change (ΔS
ο
). The results pointed out that the DNP-BSA binding was endothermic. It was shown that the stability of the drug-protein system was predominantly due to the intermolecular hydrophobic forces. Additionally, the site probing method revealed that subdomain IIA (Site I) is where DNP and BSA's binding occurs. This was validated using a molecular docking study with the most stable DNP configuration. This study might help to understand DNP's pharmacokinetics profile and toxicity as well as provides crucial information for its safe use and avoiding its toxicity.
For the past three decades, pharmaceutical research has been mainly converging to novel carrier systems and nanoparticulate colloidal technologies for drug delivery, such as nanoparticles, ...nanospheres, vesicular systems, liposomes, or nanocapsules to impart novel functions and targeting abilities. Such technologies opened the gate towards more sophisticated and effective multi-acting platform(s) which can offer site-targeting, imaging, and treatment using a single multifunctional system. Unfortunately, such technologies faced major intrinsic hurdles including high cost, low stability profile, short shelf-life, and poor reproducibility across and within production batches leading to harsh bench-to-bedside transformation.Currently, pharmaceutical industry along with academic research is investing heavily in bioconjugate structures as an appealing and advantageous alternative to nanoparticulate delivery systems with all its flexible benefits when it comes to custom design and tailor grafting along with avoiding most of its shortcomings. Bioconjugation is a ubiquitous technique that finds a multitude of applications in different branches of life sciences, including drug and gene delivery applications, biological assays, imaging, and biosensing.Bioconjugation is simple, easy, and generally a one-step drug (active pharmaceutical ingredient) conjugation, using various smart biocompatible, bioreducible, or biodegradable linkers, to targeting agents, PEG layer, or another drug. In this chapter, the different types of bioconjugates, the techniques used throughout the course of their synthesis and characterization, as well as the well-established synthetic approaches used for their formulation are presented. In addition, some exemplary representatives are outlined with greater emphasis on the practical tips and tricks of the most prominent techniques such as click chemistry, carbodiimide coupling, and avidin-biotin system.
Structural modifications of the antibacterial drug nitrofurantoin were envisioned, employing drug repurposing and biology-oriented drug synthesis, to serve as possible anticancer agents. Eleven ...compounds showed superior safety in non-cancerous human cells. Their antitumor efficacy was assessed on colorectal, breast, cervical, and liver cancer cells. Three compounds induced oxidative DNA damage in cancer cells with subsequent cellular apoptosis. They also upregulated the expression of Bax while downregulated that of Bcl-2 along with activating caspase 3/7. The DNA damage induced by these compounds, demonstrated by pATM nuclear shuttling, was comparable in both MCF7 and MDA-MB-231 (p53 mutant) cell lines. Mechanistic studies confirmed the dependence of these compounds on p53-mediated pathways as they suppressed the p53–MDM2 interaction. Indeed, exposure of radiosensitive prostatic cancer cells to low non-cytotoxic concentrations of compound 1 enhanced the cytotoxic response to radiation indicating a possible synergistic effect. In vivo antitumor activity was verified in an MCF7-xenograft animal model.
Click chemistry was used to synthesize a new series of thioquinazolinone molecules equipped with propargyl moiety,1,2,3-triazolyl and isoxazolyl rings. Our design was based on merging pharmacophores ...previously reported to exhibit COX-2 inhibitory activities to a thioquinazolinone-privileged scaffold. The synthesized compounds were subjected to in vitro cyclooxygenase COX-1/COX-2 and 15-LOX inhibition assays. Compounds 2c, 3b, 3h, 3j, and 3k showed COX-2 inhibition with IC50 (μM) 0.18, 0.19, 0.11, 0.16 and 0.17 respectively. These values were compared to celecoxib (IC50 0.05 μM), diclofenac (IC50 0.8 μM) and indomethacin (IC50 0.49 μM) reference drugs. They also showed 15-LOX inhibition with IC50 (μM) 6.21, 4.33, 7.62, 5.21 and 3.98 respectively. These values were compared with Zileuton (IC50 2.41 μM) and Meclofenamate sodium (IC50 5.64 μM) as positive controls. These compounds were further challenged by PMA-induced THP-1 differentiation assay where compounds 2c and 3j inhibited monocyte to macrophage differentiation efficiently with IC50 values of 4.78 μM and 5.63 μM, respectively, compared to that of diclofenac sodium (4.86 μM). On the other hand, 3h demonstrated a significantly increased potency compared to diclofenac in this assay (IC50 = 0.13 μM). The same compounds exhibited significant in vivo anti-inflammatory effect as indicated by the formalin-induced rat-paw edema test. Docking experiments of compounds 2c, 3b, 3h, 3j, and 3k into COX-2 binding pocket have been conducted, where strong binding interactions have been identified and effective overall docking scores have been recorded. Their drug-likeness has been assessed using Molinspiration, Molsoft and Pre-ADMET software products.
A new series of propargyl and 1,2,3-Triazolyl thioquinazolinone showed dual COX-2 and LOX inhibitory activity. Display omitted
•A new series of propargyl, triazolyl and isoxazolyl derivatives of thioquinazolinone were synthesized via click chemistry.•Compounds 2c, 3b, 3h, 3j, and 3k showed dual selective COX-2 and 15-LOX inhibition.•Compounds 2c, 3b, 3h and 3j inhibited in vitro monocyte to macrophage differentiation.•They showed in vivo anti-inflammatory activity and acceptable GIT safety on experimental animals.•Their docking experiments and drug-likeness assessment were satisfactory.
Cancer is a multifactorial disorder involving multiplicity of interrelated signaling pathways and molecular targets. To that end, a multi-target design strategy was adopted to develop some ...1,2,3-triazoles hybridized with some pharmacophoric anticancer fragments, as first-in-class simultaneous inhibitors of COX-2, 15-LOX and tumor associated carbonic anhydrase enzymes. Results revealed that compounds 5a, 5d, 8b and 8c were potent inhibitors of COX-2 and 15-LOX enzymes. COX-2 inhibitory activity was further demonstrated by the inhibition of the accumulation of 6-keto-PGF1α, a metabolite of COX-2 products in two cancer cell lines. The sulfonamide bearing derivatives 5d and 8c were effective nanomolar and submicromolar inhibitors of tumor associated hCA XII isoform, respectively. Strong to moderate inhibitory activities were observed in the in vitro antiproliferative assay on lung (A549), liver (HepG2) and breast (MCF7) cancer cell lines (IC50 2.37–28.5 μM) with high safety margins on WI-38 cells. A cytotoxic advantage of CA inhibition was observed as an increased activity against tumor cell lines expressing CA IX/XII. Further mechanistic clues for the anticancer activities of compound 5a and its sulfonamide analog 5d were derived from induction of cell cycle arrest at G2/M phase. They also triggered apoptosis via increasing expression levels of caspase-9 and Bax together with suppressing that of Bcl-2. The in vitro anti-tumor activity was reflected as reduced tumor size upon treatment with 8c in an in vivo cancer xenograft model. Docking experiments on the target enzymes supported their in vitro data and served as further molecular evidence. In silico calculations and ligand efficiency indices were promising. In light of these data, such series could offer new structural insights into the understanding and development of multi-target COX-2/15-LOX/hCA inhibitors for anticancer outcomes.
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•1,2,3-triazole-based MTDLs acting on COX-2, 15-LOX and tumor related CA were designed as anticancer agents.•Compounds 5a, 5d, 8b and 8c were potent inhibitors of COX-2 and 15-LOX, while 5d and 8c inhibited tumor associated hCA XII.•They inhibited the growth of A549, HepG2 and MCF7 cell lines. 8c reduced tumor size in an in vivo MCF7 xenograft model.•Compounds 5a and 5d induced apoptosis via increasing caspase-9 and Bax levels and downregulating Bcl-2.•Molecular docking and in silico predictions showed an overall promising lead-like characters.
As a new approach to the management of inflammatory disorders, a series of chromone-based derivatives containing a (carbamate)hydrazone moiety was designed and synthesized. The compounds were ...assessed for their ability to inhibit COX-1/2, 15-LOX, and mPGES-1, as a combination that should effectively impede the arachidonate pathway. Results revealed that the benzylcarbazates (2a-c) demonstrated two-digit nanomolar COX-2 inhibitory activities with reasonable selectivity indices. They also showed appreciable 15-LOX inhibition, in comparison to quercetin. Further testing of these compounds for mPGES-1 inhibition displayed promising activities. Intriguingly, compounds 2a-c were capable of suppressing edema in the formalin-induced rat paw edema assay. They exhibited an acceptable gastrointestinal safety profile regarding ulcerogenic liabilities in gross and histopathological examinations. Additionally, upon treatment with the test compounds, the expression of the anti-inflammatory cytokine IL-10 was elevated, whereas that of TNF-α, iNOS, IL-1β, and COX-2 were downregulated in LPS-challenged RAW264.7 macrophages. Docking experiments into the three enzymes showed interesting binding profiles and affinities, further substantiating their biological activities. Their in silico physicochemical and pharmacokinetic parameters were advantageous.
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•A new series of chromone-acylhydrazones was designed and synthesized.•Benzylcarbazates 2a-c proved to be triple inhibitors of COX-2, 15-LOX and mPGES-1.•In cellular assay, they reduced pro-inflammatory mediators similarly to celecoxib.•They decreased formalin-induced rat paw edema in vivo without ulcerogenic effects.•Benzylcarbazates 2a-c could be promising multipotent anti-inflammatory prototypes.
