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1.
Biomed Pharmacother ; 174: 116484, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38565058

RESUMO

A novel small molecule based on benzothiazole-piperazine has been identified as an effective multi-target-directed ligand (MTDL) against Alzheimer's disease (AD). Employing a medicinal chemistry approach, combined with molecular docking, MD simulation, and binding free energy estimation, compound 1 emerged as a potent MTDL against AD. Notably, compound 1 demonstrated efficient binding to both AChE and Aß1-42, involving crucial molecular interactions within their active sites. It displayed a binding free energy (ΔGbind) -18.64± 0.16 and -16.10 ± 0.18 kcal/mol against AChE and Aß1-42, respectively. In-silico findings were substantiated through rigorous in vitro and in vivo studies. In vitro analysis confirmed compound 1 (IC50=0.42 µM) as an effective, mixed-type, and selective AChE inhibitor, binding at both the enzyme's catalytic and peripheral anionic sites. Furthermore, compound 1 demonstrated a remarkable ability to reduce the aggregation propensity of Aß, as evidenced by Confocal laser scanning microscopy and TEM studies. Remarkably, in vivo studies exhibited the promising therapeutic potential of compound 1. In a scopolamine-induced memory deficit mouse model of AD, compound 1 showed significantly improved spatial memory and cognition. These findings collectively underscore the potential of compound 1 as a promising therapeutic candidate for the treatment of AD.

2.
HLA ; 103(3): e15436, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38470352

RESUMO

HLA-B*40:06:01:18 differs from HLA-B*40:06:01:02 by one nucleotide change in the 5'UTR (T > C).


Assuntos
Povo Asiático , Genes MHC Classe I , Humanos , Alelos , Regiões 5' não Traduzidas , Antígenos HLA-B/genética
3.
Genetics ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38467475

RESUMO

Asymmetric transport of cargo across axonal branches is a field of active research. Mechanisms contributing to preferential cargo transport along specific branches in vivo in wild type neurons are poorly understood. We find that anterograde synaptic vesicles preferentially enter the synaptic branch or pause at the branch point in C. elegans PLM neurons. The synaptic vesicle anterograde kinesin motor UNC-104/KIF1A regulates this vesicle behaviour at the branch point. Reduced levels of functional UNC-104 cause vesicles to predominantly pause at the branch point and lose their preference for turning into the synaptic branch. SAM-4/Myrlysin, which aids in recruitment/activation of UNC-104 on synaptic vesicles, regulates vesicle behaviour at the branch point similar to UNC-104. Increasing the levels of UNC-104 increases the preference of vesicles to go straight towards the asynaptic end. This suggests that the neuron optimises UNC-104 levels on the cargo surface to maximise the fraction of vesicles entering the branch and minimise the fraction going to the asynaptic end.

4.
Epilepsy Curr ; 24(1): 40-46, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327540

RESUMO

Dendrites are tree-like structures with tiny spines specialized to receive excitatory synaptic transmission. Spino-dendritic plasticity, driven by neural activity, underlies the maintenance of neuronal connections crucial for proper circuit function. Abnormalities in dendritic morphology are frequently seen in epilepsy. However, the exact etiology or functional implications are not yet known. Therefore, to better comprehend the structure-function significance of this dendritic pathology in epilepsy, it is necessary to identify the common spino-dendritic disturbances present in both human and experimental models. Here, we describe the dendritic and spine structural profiles found across human refractory epilepsy as well as in animal models of developmental, acquired, and genetic epilepsies.

5.
Drug Discov Today ; 29(3): 103904, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280625

RESUMO

To combat multifactorial refractory diseases, such as cancer, cardiovascular, and neurodegenerative diseases, multitarget drugs have become an emerging area of research aimed at 'synthetic lethality' (SL) relationships associated with drug-resistance mechanisms. In this review, we discuss the in silico design of dual and triple-targeted ligands, strategies by which specific 'warhead' groups are incorporated into a parent compound or scaffold with primary inhibitory activity against one target to develop one small molecule that inhibits two or three molecular targets in an effort to increase potency against multifactorial diseases. We also discuss the analytical exploration of structure-activity relationships (SARs), physicochemical properties, polypharmacology, scaffold feature extraction of US Food and Drug Administration (FDA)-approved multikinase inhibitors (MKIs), and updates regarding the clinical status of dual-targeted chemotypes.


Assuntos
Descoberta de Drogas , Polifarmacologia , Relação Estrutura-Atividade , Preparações Farmacêuticas , Ligantes , Desenho de Fármacos
6.
Epilepsy Curr ; 23(5): 324-326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901780
7.
Pharm Res ; 40(11): 2747-2758, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37833570

RESUMO

PURPOSE: There is growing interest in seeking pharmacological activation of neurolysin (Nln) for stroke treatment. Discovery of central nervous system drugs remains challenging due to the protection of the blood-brain barrier (BBB). The previously reported peptidomimetic Nln activators display unsatisfactory BBB penetration. Herein, we investigate the next generation of non-peptidomimetic Nln activators with high BBB permeability. METHODS: A BBB-mimicking model was used to evaluate their in vitro BBB permeability. Protein binding, metabolic stability, and efflux assays were performed to determine their unbound fraction, half-lives in plasma and brains, and dependence of BBB transporter P-glycoprotein (P-gp). The in vivo pharmacokinetic profiles were elucidated in healthy and stroke mice. RESULTS: Compounds KS52 and KS73 out of this generation exhibit improved peptidase activity and BBB permeability compared to the endogenous activator and previous peptidomimetic activators. They show reasonable plasma and brain protein binding, improved metabolic stability, and independence of P-gp-mediated efflux. In healthy animals, they rapidly distribute into brains and reach peak levels of 18.69% and 12.10% injected dose (ID)/ml at 10 min. After 4 h, their total brain concentrations remain 7.78 and 12.34 times higher than their A50(minimal concentration required for enhancing 50% peptidase activity). Moreover, the ipsilateral hemispheres of stroke animals show comparable uptake to the corresponding contralateral hemispheres and healthy brains. CONCLUSIONS: This study provides essential details about the pharmacokinetic properties of a new generation of potent non-peptidomimetic Nln activators with high BBB permeability and warrants the future development of these agents as potential neuroprotective pharmaceutics for stroke treatment.


Assuntos
Peptidomiméticos , Acidente Vascular Cerebral , Camundongos , Animais , Barreira Hematoencefálica/metabolismo , Peptidomiméticos/metabolismo , Metaloendopeptidases/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Permeabilidade
8.
Biosens Bioelectron ; 231: 115285, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37058958

RESUMO

As a full-fidelity simulation of human cells, tissues, organs, and even systems at the microscopic scale, Organ-on-a-Chip (OOC) has significant ethical advantages and development potential compared to animal experiments. The need for the design of new drug high-throughput screening platforms and the mechanistic study of human tissues/organs under pathological conditions, the evolving advances in 3D cell biology and engineering, etc., have promoted the updating of technologies in this field, such as the iteration of chip materials and 3D printing, which in turn facilitate the connection of complex multi-organs-on-chips for simulation and the further development of technology-composite new drug high-throughput screening platforms. As the most critical part of organ-on-a-chip design and practical application, verifying the success of organ model modeling, i.e., evaluating various biochemical and physical parameters in OOC devices, is crucial. Therefore, this paper provides a logical and comprehensive review and discussion of the advances in organ-on-a-chip detection and evaluation technologies from a broad perspective, covering the directions of tissue engineering scaffolds, microenvironment, single/multi-organ function, and stimulus-based evaluation, and provides a more comprehensive review of the progress in the significant organ-on-a-chip research areas in the physiological state.


Assuntos
Técnicas Biossensoriais , Sistemas Microfisiológicos , Animais , Humanos , Organoides , Engenharia Tecidual , Microfluídica , Dispositivos Lab-On-A-Chip
9.
Bioorg Chem ; 135: 106490, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37001472

RESUMO

In organic chemistry, the use of deuterium exchange as a tool to study the mechanism of chemical reaction has been well explored. Since two decades, the research focus on deuterated bioactive molecules has been gaining attention for investigating the therapeutic potential of deuterium replacement in a chemical structure. Recently, Food Drug Administration (FDA) approved the first deuterium-labeled drug "deutetrabenazine", and notified the deuterated drugs as new chemical entities (NCEs). Henceforth, the deuterium substitution driven structure activity relationship, preclinical pharmacokinetics, and toxicity studies were much initiated. Deuteration of a bioactive molecule often results in improved therapeutic efficacy due to the altered pharmacokinetic profile. This review provides a conceptual framework on the importance of deuterium atom in chemical structure of a drug, and its biological value in improved physiochemical properties, pharmacokinetics, biological target interaction, diagnosis, and toxicity. In addition, this review concisely updated the recent deuteration methods, chemical stability, challenges in drug development, deuterium-based imaging in diagnosis, and selected synthetic scheme of deuterated molecules.


Assuntos
Desenvolvimento de Medicamentos , Deutério/química , Preparações Farmacêuticas/química , Relação Estrutura-Atividade
10.
Drug Dev Res ; 84(4): 681-702, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36872587

RESUMO

Inhibition of specific carbonic anhydrase (CA) enzymes is a validated strategy for the development of agents to target cancer. The CA isoforms IX and XII are overexpressed in various human solid tumors wherein they play a critical role in regulating extracellular tumor acidification, proliferation, and progression. A series of novel sulfonamides based on the coumarin scaffold were designed, synthesized and characterized as potent and selective CA inhibitors. Selected compounds show significant activity and selectivity over CA I and CA II to target the tumor-associated CA IX and CA XII with high inhibition activity at the single digit nanomolar level. Twelve compounds were identified to be more potent compared with acetazolamide (AAZ) control to inhibit CA IX while one was also more potent than AAZ to inhibit CA XII. Compound 18f (Ki's = 955 nM, 515 nM, 21 nM and 5 nM for CA's I, II, IX, and XII, respectively) is highlighted as a novel CA IX and XII inhibitor for further development.


Assuntos
Cumarínicos , Neoplasias , Humanos , Anidrase Carbônica IX/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade , Cumarínicos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Acetazolamida/farmacologia
11.
Hernia ; 27(5): 1299-1306, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36427167

RESUMO

PURPOSE: Value driven outcome (VDO) initiative is a value-based, patient-focused tool which utilizes a clinical outcome-based approach to optimize value of care based on clinically relevant quality indicators and costs required to achieve the care. In this study, we evaluate the impact of a VDO initiative on groin hernia repair, a commonly performed elective surgery in our hospital. METHODS: A VDO initiative was implemented in 2019 to encourage elective inguinal hernia repair to be performed at a day surgery setting. A comparison of outcomes was made between hernia surgeries performed in 2019 with those in 2020 and 2021. Pre-defined criteria were used to select patients that can be operated at a day surgery setting. Patients' expectations were addressed preoperatively about day surgery procedure and postoperative recovery. Day surgery bundles were used to standardize pre- and post-surgery protocols. Pain control was optimized using a specialized local anesthesia regime. RESULTS: A total of 263 laparoscopic hernia surgeries were performed between May 2019 and December 2021. After implementation of VDO initiative, the percentage of patients discharged within 24 h increased from 78% in year 2019 to 97% in year 2020 and 99% in year 2021. Conversion rate for day surgery to short stay decreased from 9% in year 2019 to 1% in year 2020 and 2% in year 2021. In 2019 to 2021, there were no 30-day readmission, no hernia recurrence in 90 days, no conversion to open surgery. CONCLUSION: VDO initiative is a promising tool to deliver better value-based care for patients undergoing endo-laparoscopic inguinal hernia repair.


Assuntos
Hérnia Inguinal , Laparoscopia , Humanos , Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Virilha/cirurgia , Laparoscopia/métodos , Manejo da Dor
12.
Front Chem ; 10: 1051678, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518978

RESUMO

Over the past few decades, various bioactive material-based scaffolds were investigated and researchers across the globe are actively involved in establishing a potential state-of-the-art for bone tissue engineering applications, wherein several disciplines like clinical medicine, materials science, and biotechnology are involved. The present review article's main aim is to focus on repairing and restoring bone tissue defects by enhancing the bioactivity of fabricated bone tissue scaffolds and providing a suitable microenvironment for the bone cells to fasten the healing process. It deals with the various surface modification strategies and smart composite materials development that are involved in the treatment of bone tissue defects. Orthopaedic researchers and clinicians constantly focus on developing strategies that can naturally imitate not only the bone tissue architecture but also its functional properties to modulate cellular behaviour to facilitate bridging, callus formation and osteogenesis at critical bone defects. This review summarizes the currently available polymeric composite matrices and the methods to improve their bioactivity for bone tissue regeneration effectively.

13.
Life (Basel) ; 12(11)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36431014

RESUMO

In men, prostate cancer (PC) is the most frequently diagnosed cancer, causing an estimated 375,000 deaths globally. Currently, existing therapies for the treatment of PC, notably metastatic cases, have limited efficacy due to drug resistance and problematic adverse effects. Therefore, it is imperative to discover and develop novel drugs for treating PC that are efficacious and do not produce intolerable adverse or toxic effects. Condensed quinolines are naturally occurring anticancer compounds. In this study, we determined the in vitro efficacy of IND-2 (4-chloro-2-methylpyrimido[1″,2″:1,5]pyrazolo[3,4-b]quinolone) in the PC lines, PC-3 and DU-145. IND-2 significantly inhibited the proliferation of PC-3 and DU-145, with IC50 values of 3 µM and 3.5 µM, respectively. The incubation of PC-3 cells with 5 and 10 µM of IND-2 caused the loss of the mitochondrial membrane potential in PC-3 cells. Furthermore, IND-2, at 5 µM, increased the expression of cleaved caspase-3, cleaved caspase-7 and cleaved poly (ADP-ribose) polymerase (PARP). The incubation of PC-3 cells with 5 µM of IND-2 significantly decreased the expression of the apoptotic protein, B-cell lymphoma 2 (Bcl-2). Furthermore, 5 and 10 µM of IND-2 produced morphological changes in PC-3 cells characteristic of apoptosis. Interestingly, IND-2 (2.5, 5 and 10 µM) also induced mitotic catastrophe in PC-3 cells, characterized by the accumulation of multinuclei. The incubation of DU-145 cells with 1.25 and 5 µM of IND-2 significantly increased the levels of reactive oxygen species (ROS). Finally, IND-2, at 10 µM, inhibited the catalytic activity of topoisomerase IIα. Overall, our findings suggest that IND-2 could be a potential lead compound for the development of more efficacious compounds for the treatment of PC.

14.
3 Biotech ; 12(11): 316, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36276437

RESUMO

Healthy skin protects from pathogens, water loss, ultraviolet rays, and also maintains homeostasis conditions along with sensory perceptions in normal circumstances. Skin wound healing mechanism is a multi-phased biodynamic process that ultimately triggers intercellular and intracellular mechanisms. Failure to implement the normal and effective healing process may result in chronic injuries and aberrant scarring. Chronic wounds lead to substantial rising healthcare expenditure, and innovative methods to diagnose and control severe consequences are urgently needed. Skin tissue engineering (STE) has achieved several therapeutic accomplishments during the last few decades, demonstrating tremendous development. The engineered skin substitutes provide instant coverage for extensive wounds and facilitate the prevention of microbial infections and fluid loss; furthermore, they help in fighting inflammation and allow rapid neo-tissue formation. The current review primarily focused on the wound recovery and restoration process and the current conditions of STE with various advancements and complexities associated with different strategies such as cell sources, biopolymers, innovative fabrication techniques, and growth factors delivery systems.

15.
Biomed Mater ; 17(6)2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36113451

RESUMO

Graphene oxide (GO) offers a distinct opportunity in the field of biomedical engineering owing to its exceptionally high mechanical strength, excellent electrical conductivity, high optical transparency, and favorable biocompatibility. In this article, nanocomposite biocompatible GO-based scaffolds (chitosan/gelatin/nanobioglass/GO) Ch-G-NBG-GO were successfully fabricated through freeze drying technique (-40 °C) and evaluated for various physico-chemical and biological properties. The prepared Ch-G-NBG-GO composites have been investigated for their structural, physiochemical, and surface morphology via x-ray diffraction (XRD), high resolution scanning electron microscope, Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), energy-dispersive x-ray Spectroscopy and, differential scanning colorimetry (DSC) respectively. The morphological analysis showed the porous interconnected network of scaffold formed. Average pore size for the Ch-G-NBG-GO scaffolds were in between 90 and 120 µm, which was very close to the control scaffolds. XRD data revealed the successful incorporation of NBG and GO and distribution across the scaffolds. Porosity of the fabricated scaffolds were in the range between 75.3% and 77.3% which was very close to the control scaffold with 79% porosity. The studies also reveal that after GO incorporation, the weight loss reduced (0.11 ± 0.02-0.095 ± 0.03), scaffolds were firmly stable at room temperature even after a long duration of 28 d. The crystallinity added to the scaffolds due to addition of GO nanoparticles improved the mechanical strength of these scaffolds. The compressive modulus changed from (5.7 to 8.51) MPa after GO addition. Swelling ratio changed drastically especially in case of Ch-NBG-90%GO (4.9 ± 0.04-4 ± 0.01). DSC and TGA data revealed the thermal stability of GO incorporated scaffolds due to the proper interaction between GO/NBG with chitosan-gelatin blend. The scaffold's potential for bone tissue engineering was evaluated by testing its cytocompatibility for MG-63 cell line. It revealed suitable cell attachment and proliferation of cells compared to the Ch-G-NBG scaffold. MTT assay showed that Ch-G-NBG-GO scaffold below 90% GO concentration possess best biocompatibility. But in case of Ch-G-NBG-90%GO scaffold, the cell proliferation was reduced when compared to control scaffolds. Alkaline phosphatase activity suggested improved osteogenic differentiation of MG-63 cells over GO based scaffolds and this was due to the osteogenic potential of NBG and GO present in the scaffolds. Based on these results, the nano-biocomposite scaffold appears to have the potential for utilization in bone tissue restoration, replacement and regeneration.


Assuntos
Quitosana , Fosfatase Alcalina , Regeneração Óssea , Osso e Ossos , Quitosana/química , Gelatina/química , Grafite , Osteogênese , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual/métodos , Tecidos Suporte/química
16.
eNeuro ; 9(4)2022.
Artigo em Inglês | MEDLINE | ID: mdl-35981870

RESUMO

Two key features endow Drosophila Down syndrome cell adhesion molecule 1 (Dscam1) with the potential to provide a ubiquitous code for neuronal arbor self-avoidance. First, Dscam1 contains three large cassettes of alternative exons, so that stochastic alternative splicing yields 19,008 Dscam1 isoforms with different Ig ectodomains. Second, each neuron expresses a different subset of Dscam1 isoforms, and isoform-specific homophilic binding causes repulsion. This results in even spacing of self-arbors, while processes of other neurons can intermingle and share the same synaptic partners. In principle, this Dscam1 code could ensure arbor spacing of all neurons in Drosophila This model is strongly supported by studies on dendrite spacing in the peripheral nervous system and studies on axonal branch segregation during brain development. However, the situation is less clear for central neuron dendrites, the major substrate for synaptic input in the CNS. We systematically tested the role of Dscam1 for dendrite growth and spacing in eight different types of identified central neurons. Knockdown of Dscam1 causes severe dendritic clumping and length reductions in efferent glutamatergic and aminergic neurons. The primary cause for these dendritic phenotypes could be impaired self-avoidance, a growth defect, or both. In peptidergic efferent neurons, many central arbors are not formed, arguing for a growth defect. By contrast, knockdown of Dscam1 does not affect dendrite growth or spacing in any of the five different types of interneurons tested. Axon arbor patterning is not affected in any neuron type tested. We conclude that Dscam1 mediates diverse, neuron type-specific functions during central neuron arbor differentiation.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Moléculas de Adesão Celular , Dendritos , Neurônios , Isoformas de Proteínas
17.
Drug Discov Today ; 27(10): 103322, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35868626

RESUMO

Alzheimer's disease (AD) is a detrimental neurodegenerative disease that progressively worsens with time. Clinical options are limited and only provide symptomatic relief to AD patients. The search for effective anti-AD compounds is ongoing with a few already in Phase III clinical trials, yet to be approved. Heterocycles containing nitrogen are important to biological processes owing to their abundance in nature, their function as subunits of biological molecules and/or macromolecular structures, and their biological activities. The present review discusses previously used strategies, SAR, relevant in vitro and in vivo studies, and success stories of nitrogen-containing heterocyclic compounds in AD drug discovery. Also, we propose strategies for designing and developing novel potent anti-AD small molecules that can be used as treatments for AD.


Assuntos
Doença de Alzheimer , Compostos Heterocíclicos , Doenças Neurodegenerativas , Doença de Alzheimer/tratamento farmacológico , Descoberta de Drogas , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/uso terapêutico , Humanos , Nitrogênio
18.
Bioorg Med Chem Lett ; 64: 128669, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292343

RESUMO

Modulating peptidase neurolysin (Nln) has been identified as a potential cerebroprotective target for the development of therapeutics for ischemic stroke. Continued structure-activity relationship studies on peptidomimetic small molecule activators of Nln bearing electron-donating and electron- withdrawing functionalized phenyls are explored. Incorporation of fluorine or trifluoromethyl groups produces Nln activators with enhanced A50, while methoxy substitution produces derivatives with enhanced Amax. Selected activators containing methoxy or trifluoromethyl substitution are selective for Nln over related peptidases and possess increased blood-brain barrier penetrability than initial hits.


Assuntos
Peptidomiméticos , Metaloendopeptidases/metabolismo , Peptídeo Hidrolases/metabolismo , Peptidomiméticos/farmacologia , Relação Estrutura-Atividade
20.
Phys Rev E ; 104(2-1): 024126, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34525551

RESUMO

The behavior of many magnetic and dielectric solids, and the more contemporary magnetic superlattices, is governed by dipolar interactions. They are anisotropic and long ranged, having varied consequences ranging from ground states with complicated magnetic order to the presence of glassy dynamics characterized by a plethora of relaxation times. These systems are well captured by the dipolar Ising model (DIM) with nearest-neighbor exchange interactions (J) and long-range dipolar interactions (D). Depending on the relative interaction strength Γ=J/D, there are four phases of distinct magnetic order and symmetry. Using Monte Carlo simulations, we perform deep quenches to study domain growth or coarsening in the d=3 DIM. This important nonequilibrium phenomenon has not been addressed as dipolar interactions are notoriously difficult to handle theoretically. Our study reveals that, in spite of the anisotropy in interactions and diversity in ground state configurations, we observe universality in the ordering dynamics of all phases.

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