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BACKGROUND: The effects of collagen-induced arthritis (CIA), a model of systemic inflammation, on brain regional molecular markers associated with neurological disorders are uncertain. OBJECTIVE: This study investigated the brain regional molecular changes in markers associated with inflammation and neuronal dysfunction in a CIA model. METHODS: Fourteen male Sprague Dawley rats were divided into control (n = 5) or CIA (n = 9) groups. 10 weeks after CIA induction, brain tissue was collected. Brain regional mRNA expression of inflammatory markers (IL-1ß and IL-6), apoptotic markers (BAX and Bcl2) and neurotrophic factors (BDNF, CREB and TrkB) was determined. Monoamine distribution and abundance in different brain regions were determine by mass spectrometry imaging (MSI). RESULTS: Neuroinflammation was confirmed in the CIA group by increased IL-ß mRNA expression, concurrent with an increased BAX/Bcl2 ratio. The mRNA expression of CREB was increased in the midbrain and hippocampus while BDNF was increased and TrkB was decreased across all brain regions in CIA compared to control animals. Serotonin was decreased in the midbrain and hippocampus while dopamine was decreased in the striatum of CIA rats, compared to controls. CONCLUSION: CIA resulted in neuroinflammation concurrent with an apoptotic state and aberrant expression of neurotrophic factors and monoamines in the brain, suggestive of neurodegeneration.
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Renal dysfunction is important in preeclampsia (PE) pathophysiology and has not been fully explored in the arginine vasopressin (AVP) rat model of PE. This study aimed to determine kidney toxicity associated with this model. Female Sprague Dawley rats (n = 24) were subcutaneously infused with AVP or saline for 18 days. Urine samples (GD8, 14 and 18) were used to determine the levels of albumin, VEGF-A, clusterin, NGAL/Lipocalin-2, KIM-1, cystatin C, TIMP-1, ß2M and OPN via Multiplex ELISAs. Albumin, and NGAL/lipocalin-2 were significantly elevated in the PAVP vs PS group on GD14 and GD18 (p < 0.001) respectively. VEGF-A significantly decreased in the pregnant vs non-pregnant groups on GD14 and 18 (p < 0.001). Clusterin (p < 0.001) and OPN (p < 0.05) were significantly higher in the PAVP vs PS group on GD18. Cystatin C and KIM-1 are significantly upregulated in the PAVP vs PS groups throughout gestation (p < 0.05). ß2M is significantly elevated in the PAVP vs PS group on GD14 and 18 (p < 0.05). AVP elevated the urinary levels of the kidney injury biomarkers and replicated the renal dysfunction associated with PE development. Our findings confirm the potential applications of this model in studying the mechanisms underlying renal damage in PE.
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In Africa, there is currently a paucity of data on the epidemiology of depression, its treatment and management. The prevalence of depression is severely underestimated, with unique circumstances and societal risk factors associated with depression and its public awareness. Treating and managing depression is confounded by an inaccessibility to efficient and low-cost treatments for patients with depression. The aetiology of depression is multifactorial, with various theories implicating multiple neuronal networks. Despite this, the treatment of depression is one-dimensional focussing on outdated theories of depression and mainly targeting dysfunctional neurotransmitter pathways. Hence, it is not surprising that there is a significant increase in the prevalence of patients suffering from treatment resistant depression (TRD), with a large portion of patients deriving little clinical benefit from these traditional anti-depressant therapies. This highlights the need for more effective treatment strategies for depression, especially applicable to resource limited environments such as Africa, where there is little investment in public healthcare resources towards managing mental health disorders. The clinical potential of using ketamine in managing depression has received considerable attention in the past two decades, with the FDA approving esketamine for the management of TRD in 2019. This widespread attention has significantly increased ketamine's appeal as a novel antidepressant. Consequently, many ketamine infusion clinics have been established in Africa. However, there is little regulation or guidance for ketamine infusions. Furthermore, while esketamine is expensive and hence inaccessible to a large portion of the African population, racemic ketamine is significantly cheaper and has demonstrated clinical potential. However, there is currently a limited understanding of the neurological mechanisms of action of racemic ketamine in treating and managing depression, especially in a diverse African population. Therefore, this review aims to provide an African context of depression and the therapeutic potential of ketamine by highlighting aspects of its molecular mechanism of action.
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Hypothalamic-pituitary-adrenal (HPA) axis dysregulation is linked to the pathophysiology of depression. Although exogenous adrenocorticotropic hormone (ACTH) is associated with a depressive-like phenotype in rodents, comprehensive neurobehavioral and mechanistic evidence to support these findings are limited. Sprague-Dawley rats (male, n = 30; female, n = 10) were randomly assigned to the control (male, n = 10) or ACTH (male, n = 20; female n = 10) groups that received saline (0.1 ml, sc.) or ACTH (100 µg/day, sc.), respectively, for two weeks. Thereafter, rats in the ACTH group were subdivided to receive ACTH plus saline (ACTH_S; male, n = 10; female, n = 5; 0.2 ml, ip.) or ACTH plus imipramine (ACTH_I; male, n = 10; female, n = 5;10 mg/kg, ip.) for a further four weeks. Neurobehavioral changes were assessed using the forced swim test (FST), the sucrose preference test (SPT), and the open field test (OFT). Following termination, the brain regional mRNA expression of BDNF and CREB was determined using RT-PCR. After two-weeks, ACTH administration significantly increased immobility in the FST (p = 0.03), decreased interaction with the center of the OFT (p < 0.01), and increased sucrose consumption (p = 0.03) in male, but not female rats. ACTH administration significantly increased the expression of BDNF in the hippocampus and CREB in all brain regions in males (p < 0.05), but not in female rats. Imipramine treatment did not ameliorate these ACTH-induced neurobehavioral or molecular changes. In conclusion, ACTH administration resulted in a sex-specific onset of depressive-like symptoms and changes in brain regional expression of neurotrophic factors. These results suggest sex-specific mechanisms underlying the development of depressive-like behavior in a model of ACTH-induced HPA axis dysregulation.
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Hormônio Adrenocorticotrópico , Fator Neurotrófico Derivado do Encéfalo , Sistema Hipotálamo-Hipofisário , Imipramina , Sistema Hipófise-Suprarrenal , Animais , Feminino , Masculino , Ratos , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Depressão/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Imipramina/farmacologia , Sistema Hipófise-Suprarrenal/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Hesperidin, a flavanone commonly found in citrus fruits and herbal formulations, has emerged as a potential new therapeutic agent for modulating several diseases. Since pre-eclampsia is a growing public health threat, it may negatively impact the economy and increase the disease burden of South Africa. Phytocompounds are easily accessible, demonstrate minimal side effects, and may confer novel medicinal options as a treatment and preventive preference. OBJECTIVE: To investigate the physiological, biochemical, and hematological outcomes of hesperidin in an arginine vasopressin (AVP)-induced rodent model of pre-eclampsia. METHODS: Female Sprague-Dawley rats were surgically implanted with mini-osmotic pumps to deliver AVP (200 ng/h) subcutaneously. Animals were treated with hesperidin at 200 mg/kg.b.w via oral gavage for 14 days. Systolic and diastolic blood pressures were measured on GD 7, 14, and 18 using a non-invasive tail-cuff method and were euthanized on GD 21. RESULTS: The findings showed that hesperidin administration significantly decreased blood pressure (P < 0.05) and urinary protein levels in pregnant rats (P < 0.001). Placental and individual pup weight also increased significantly in the pregnant hesperidin-treated groups compared to AVP untreated groups (P < 0.001). Biochemical and hematological markers such as white blood cell count and lymphocyte levels differed significantly (P < 0.05) in AVP groups treated with and without hesperidin. CONCLUSION: Our results suggest that hesperidin is an antihypertensive agent with modes of action associated with its diuretic and blood pressure lowering effects and reduction of proteinuria in AVP-induced pre-eclamptic rats.
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Hesperidina , Pré-Eclâmpsia , Humanos , Ratos , Feminino , Gravidez , Animais , Pré-Eclâmpsia/tratamento farmacológico , Arginina Vasopressina/metabolismo , Arginina Vasopressina/farmacologia , Arginina Vasopressina/uso terapêutico , Hesperidina/farmacologia , Hesperidina/metabolismo , Hesperidina/uso terapêutico , Placenta/metabolismo , Ratos Sprague-Dawley , Pressão SanguíneaRESUMO
PURPOSE OF REVIEW: Preeclampsia (PE) is a leading global cause of maternal and fetal morbidity and mortality. The heterogeneity of this disorder contributes to its elusive etiology. Due to the ethical constraints surrounding human studies, animal models provide a suitable alternative for investigation into PE pathogenesis and novel therapeutic strategies. The purpose of this review is to compare and contrast the various rodent models used to study PE, in order to demonstrate their value in investigating and identifying different characteristics of this disorder. RECENT FINDINGS: Several approaches have been employed to create an appropriate animal model of PE, including surgical, genetic manipulation, and pharmacological methods in an attempt to mimic the maternal syndrome. Despite the absence of a model to completely model PE, these models have provided valuable information concerning various aspects of PE pathogenesis and novel therapeutic strategies and have led to the discovery of potential predictive markers of PE. Rodent and murine models have contributed significantly to the study of the pathology associated with specific aspects of the disorder. As a single fully encompassing animal model of PE remains absent, the use of a combination of models has potential value in understanding its etiology as well as in new treatment and management strategies.
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Hipertensão , Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Camundongos , Animais , Pré-Eclâmpsia/genética , Placenta , Roedores , Modelos AnimaisRESUMO
The visualization of small metabolites by MALDI mass spectrometry imaging in brain tissue sections is challenging due to low detection sensitivity and high background interference. We present an on-tissue chemical derivatization MALDI mass spectrometry imaging approach for the comprehensive mapping of carboxyls and aldehydes in brain tissue sections. In this approach, the AMPP (1-(4-(aminomethyl)phenyl)pyridin-1-ium chloride) derivatization reagent is used for the covalent charge-tagging of molecules containing carboxylic acid (in the presence of peptide coupling reagents) and aldehydes. This includes free fatty acids and the associated metabolites, fatty aldehydes, dipeptides, neurotoxic reactive aldehydes, amino acids, neurotransmitters and associated metabolites, as well as tricarboxylic acid cycle metabolites. We performed sensitive ultrahigh mass resolution MALDI-MS detection and imaging of various carboxyl- and aldehyde-containing endogenous metabolites simultaneously in rodent brain tissue sections. We verified the AMPP-derivatized metabolites by tandem MS for structural elucidation. This approach allowed us to image numerous aldehydes and carboxyls, including certain metabolites which had been undetectable in brain tissue sections. We also demonstrated the application of on-tissue derivatization to carboxyls and aldehydes in coronal brain tissue sections of a nonhuman primate Parkinson's disease model. Our methodology provides a powerful tool for the sensitive, simultaneous spatial molecular imaging of numerous aldehydes and carboxylic acids during pathological states, including neurodegeneration, in brain tissue.
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Aldeídos , Encéfalo , Animais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Encéfalo/diagnóstico por imagem , Aminoácidos/análise , Ácidos Carboxílicos/análiseRESUMO
Virulent Enterobacterale strains expressing serine and metallo-ß-lactamases (MBL) genes have emerged responsible for conferring resistance to hard-to-treat infectious diseases. One strategy that exists is to develop ß-lactamase inhibitors to counter this resistance. Currently, serine ß-lactamase inhibitors (SBLIs) are in therapeutic use. However, an urgent global need for clinical metallo-ß-lactamase inhibitors (MBLIs) has become dire. To address this problem, this study evaluated BP2, a novel beta-lactam-derived ß-lactamase inhibitor, co-administered with meropenem. According to the antimicrobial susceptibility results, BP2 potentiates the synergistic activity of meropenem to a minimum inhibitory concentration (MIC) of ≤1 mg/L. In addition, BP2 is bactericidal over 24 h and safe to administer at the selected concentrations. Enzyme inhibition kinetics showed that BP2 had an apparent inhibitory constant (Kiapp) of 35.3 µM and 30.9 µM against New Delhi Metallo-ß-lactamase (NDM-1) and Verona Integron-encoded Metallo-ß-lactamase (VIM-2), respectively. BP2 did not interact with glyoxylase II enzyme up to 500 µM, indicating specific (MBL) binding. In a murine infection model, BP2 co-administered with meropenem was efficacious, observed by the >3 log10 reduction in K. pneumoniae NDM cfu/thigh. Given the promising pre-clinical results, BP2 is a suitable candidate for further research and development as an (MBLI).
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OBJECTIVE: To assess renal injury in an arginine vasopressin (AVP) rodent model of preeclampsia. STUDY DESIGN: Urinary expression of kidney injury molecule-1 (KIM-1), urinary protein and creatinine was determined in rodents (n = 24; pregnant AVP, pregnant saline, non-pregnant AVP and non-pregnant saline), which received a continuous dose of either AVP or saline via subcutaneous mini osmotic pumps for 18 days, using a Multiplex kidney toxicity immunoassay. Renal morphology was assessed using haematoxylin and eosin staining and transmission electron microscopy. The immunolocalization of KIM-1 and podocalyxin was qualitatively evaluated using immunohistochemistry. RESULTS: Urinary KIM-1 and urinary protein levels were significantly increased in treated vs. untreated rats on gestational days 8 (p < 0.05), 14 (p < 0.001) and 18 (p < 0.001). The pregnant rats displayed a lower trend of creatinine compared to the non-pregnant groups, albeit non-significantly. KIM-1 was immunolocalized in the proximal convoluted tubules in AVP treated vs. untreated groups. In contrast, podocalyxin was weakly immunostained within glomeruli of pregnant AVP treated vs. pregnant untreated rats. Histological evaluation revealed reduced Bowman's space, with some tubular and blood vessel necrosis in the pregnant treated group. Ultrastructural observations included effacement and fusion of podocyte foot processes, glomerular basement membrane abnormalities, podocyte nuclear crenations, mitochondrial oedema and cristae degeneration with cytoplasmic lysis within treated tissue. CONCLUSION: Our findings demonstrate region-specific kidney injury particularly glomerular impairment and endothelial injury in AVP-treated rats. The findings highlight the utility of this model in studying the mechanisms driving renal damage in a rodent model of preeclampsia.
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Arginina Vasopressina , Pré-Eclâmpsia , Animais , Feminino , Humanos , Ratos , Arginina Vasopressina/metabolismo , Creatinina , Rim/metabolismo , Pré-Eclâmpsia/metabolismo , Roedores/metabolismoRESUMO
ß-lactams are the most prescribed class of antibiotics due to their potent, broad-spectrum antimicrobial activities. However, alarming rates of antimicrobial resistance now threaten the clinical relevance of these drugs, especially for the carbapenem-resistant Enterobacterales expressing metallo-ß-lactamases (MBLs). Antimicrobial agents that specifically target these enzymes to restore the efficacy of last resort ß-lactam drugs, that is, carbapenems, are therefore desperately needed. Herein, we present a cyclic zinc chelator covalently attached to a ß-lactam scaffold (cephalosporin), that is, BP1. Observations from in vitro assays (with seven MBL expressing bacteria from different geographies) have indicated that BP1 restored the efficacy of meropenem to ≤ 0.5 mg/L, with sterilizing activity occurring from 8 h postinoculation. Furthermore, BP1 was nontoxic against human hepatocarcinoma cells (IC50 > 1000 mg/L) and exhibited a potency of (Kiapp) 24.8 and 97.4 µM against Verona integron-encoded MBL (VIM-2) and New Delhi metallo ß-lactamase (NDM-1), respectively. There was no inhibition observed from BP1 with the human zinc-containing enzyme glyoxylase II up to 500 µM. Preliminary molecular docking of BP1 with NDM-1 and VIM-2 sheds light on BP1's mode of action. In Klebsiella pneumoniae NDM infected mice, BP1 coadministered with meropenem was efficacious in reducing the bacterial load by >3 log10 units' postinfection. The findings herein propose a favorable therapeutic combination strategy that restores the activity of the carbapenem antibiotic class and complements the few MBL inhibitors under development, with the ultimate goal of curbing antimicrobial resistance.
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Carbapenêmicos , Inibidores de beta-Lactamases , Animais , Humanos , Camundongos , Carbapenêmicos/farmacologia , Inibidores de beta-Lactamases/farmacologia , Meropeném/farmacologia , Lactamas , Simulação de Acoplamento Molecular , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , beta-Lactamas/farmacologia , Monobactamas , Zinco/farmacologiaRESUMO
This study compares three different mating techniques in Sprague-Dawley rats, using the pregnancy rate as the main indicator of success. It provides recommendations for timed-pregnancy experiments to achieve an appropriate sample size for the study of human pregnancy disorders. The implementation of a preconditioning phase, determination of the estrous cycle, the use of two mating strategies (Lee-Boot and Whitten effect), female: male mating ratios, and cohabitation duration should be considered as they improve the mating success rate.
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Ciclo Estral , Reprodução , Animais , Feminino , Humanos , Masculino , Gravidez , Taxa de Gravidez , Ratos , Ratos Sprague-DawleyRESUMO
Mass spectrometry imaging (MSI) is a powerful technique that combines the ability of microscopy to provide spatial information about multiple molecular species with the specificity of mass spectrometry (MS) for unlabeled mapping of analytes in diverse biological tissues. Initial pharmacological applications focused on drug distributions in different organs, including the compartmentalized brain. However, recent technological advances in instrumentation, software, and chemical tools have allowed its use in quantitative spatial omics. It now enables visualization of distributions of diverse molecules at high lateral resolution in studies of the pharmacokinetic and neuropharmacodynamic effects of drugs on functional biomolecules. Therefore, it has become a versatile technique with a multitude of applications that have transformed neuropharmacological research and enabled research into brain physiology at unprecedented resolution, as described in this review.
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Neurofarmacologia , Humanos , Espectrometria de Massas/métodosRESUMO
In resource-limited settings, such as South Africa, hypertensive disorders of pregnancy such as preeclampsia, is the most common direct cause of maternal deaths. Current management strategies of preeclampsia primarily involve the use of pharmaceutical drugs, which are frequently associated with undesirable side-effects. Moreover, these drugs are often not easily accessible due to financial and economic constraints. Consequently, many patients rely on traditional medicine obtained from medicinal plants to manage health-related conditions. Angiotensin-converting enzyme inhibitors are widely used drugs for the management of preeclampsia. This narrative review aims to highlight the use of indigenous medicinal plants from South Africa with Angiotensin-converting enzyme inhibitory activity whilst also evaluating their potential use in the treatment of hypertension in pregnancy. This information will influence traditional healers and sangomas in their patient management. Furthermore, the antihypertensive potential of these plants will be unraveled thus facilitating the development of new naturally occurring pharmaceutical products to reduce maternal and neonatal mortality and morbidity.
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Rodent models have contributed greatly to our understanding of preeclampsia (PE) progression in humans, however to-date no model has been able to effectively replicate the clinical presentation of the disease. This study aimed to provide a thorough physiological characterization of the arginine vasopressin (AVP)-induced rat model of PE to determine its applicability in studying the pathophysiology of PE. Female Sprague Dawley rats (n = 24) were separated into four groups (n = 6 per group) viz., pregnant AVP, pregnant saline, non-pregnant AVP, and non-pregnant saline. All animals received a continuous dose of either AVP (150 ng/h) or saline via subcutaneous mini osmotic pumps for 18 days. Full physiological characterization of the model included measuring systolic and diastolic blood pressure, and collecting urine and blood samples for biochemical analysis. AVP infusion significantly increased blood pressure and urinary protein levels in the pregnant rats (p < 0.05). Biochemical markers measured, differed significantly in the AVP-treated vs the pregnant saline groups (p < 0.05). Placental and individual pup weight decreased significantly in the pregnant AVP vs pregnant saline group (p < 0.05). The physiological and hematological data confirm the usefulness of this rat model in the study of PE, since AVP-induced vasoconstriction increases peripheral resistance and successfully mimics the pathological changes associated with PE development in humans.Abbreviations: PE: preeclampsia; AVP: arginine vasopressin; ISSHP: International Society for the Study of Hypertension in Pregnancy; ACOG: American College of Obstetricians and Gynecologists; RUPP: reduced uterine perfusion pressure; sFlt-1: soluble fms-like tyrosine kinase; VEGF: vascular endothelial growth factor; PlGF: placental growth factor; AVP: arginine vasopressin; PAVP: pregnant AVP-treated; PS: pregnant saline; GD: gestational day; ALT: alanine transaminase; NAVP: non-pregnant AVP-treated; NS: non-pregnant saline; AST: aspartate aminotransferase; HDL: high-density lipoprotein; RBC: red blood cell; RAAS: renin-angiotensin aldosterone system; HELLP: hemolysis, elevated liver enzymes, low platelet.
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Pré-Eclâmpsia , Animais , Arginina Vasopressina , Feminino , Placenta , Fator de Crescimento Placentário , Pré-Eclâmpsia/induzido quimicamente , Gravidez , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio VascularRESUMO
Mycobacterium tuberculosis cell wall is intricate and impermeable to many agents. A D, D-carboxypeptidase (DacB1) is one of the enzymes involved in the biosynthesis of cell wall peptidoglycan and catalyzes the terminal D-alanine cleavage from pentapeptide precursors. Catalytic activity and mechanism by which DacB1 functions is poorly understood. Herein, we investigated the acylation mechanism of DacB1 by ß-lactams using a 6-membered ring transition state model that involves a catalytic water molecule in the reaction pathway. The full transition states (TS) optimization plus frequency were achieved using the ONIOM (B3LYP/6-31 + G(d): AMBER) method. Subsequently, the activation free energies were computed via single-point calculations on fully optimized structures using B3LYP/6-311++(d,p): AMBER and M06-2X/6-311++(d,p): AMBER with an electronic embedding scheme. The 6-membered ring transition state is an effective model to examine the inactivation of DacB1 via acylation by ß-lactams antibiotics (imipenem, meropenem, and faropenem) in the presence of the catalytic water. The ΔG# values obtained suggest that the nucleophilic attack on the carbonyl carbon is the rate-limiting step with 13.62, 19.60 and 30.29 kcal mol-1 for Imi-DacB1, Mero-DacB1 and Faro-DacB1, respectively. The electrostatic potential (ESP) and natural bond orbital (NBO) analysis provided significant electronic details of the electron-rich region and charge delocalization, respectively, based on the concerted 6-membered ring transition state. The stabilization energies of charge transfer within the catalytic reaction pathway concurred with the obtained activation free energies. The outcomes of this study provide important molecular insight into the inactivation of D, D-carboxypeptidase by ß-lactams.Communicated by Ramaswamy H. Sarma.
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Mycobacterium tuberculosis , Peptidil Transferases , Acilação , Alanina/farmacologia , Antibacterianos/farmacologia , Carbono , Carboxipeptidases/metabolismo , Imipenem/farmacologia , Meropeném/farmacologia , Monobactamas/farmacologia , Peptidoglicano/metabolismo , Peptidil Transferases/química , Peptidil Transferases/metabolismo , Água , beta-Lactamas/química , beta-Lactamas/farmacologiaRESUMO
HIV-1 protease (HIV-1 PR) is an essential enzyme for the replication process of its virus, and therefore considered an important target for the development of drugs against the acquired immunodeficiency syndrome (AIDS). Our previous study shows that the catalytic mechanism of subtype B/C-SA HIV-1 PR follows a one-step concerted acyclic hydrolysis reaction process using a two-layered ONIOM B3LYP/6-31++G(d,p) method. This present work is aimed at exploring the proposed mechanism of the proteolysis catalyzed by HIV-1 PR and to ensure our proposed mechanism is not an artefact of a single theoretical technique. Hence, we present umbrella sampling method that is suitable for calculating potential mean force (PMF) for non-covalent ligand/substrate-enzyme association/dissociation interactions which provide thermodynamic details for molecular recognition. The free activation energy results were computed in terms of PMF analysis within the hybrid QM(DFTB)/MM approach. The theoretical findings suggest that the proposed mechanism corresponds in principle with experimental data. Given our observations, we suggest that the QM/MM MD method can be used as a reliable computational technique to rationalize lead compounds against specific targets such as the HIV-1 protease.
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Inibidores da Protease de HIV , HIV-1 , Protease de HIV/química , Inibidores da Protease de HIV/química , HIV-1/metabolismo , Simulação de Dinâmica Molecular , TermodinâmicaRESUMO
A wide range of microorganisms can infect the central nervous system (CNS). The immune response of the CNS provides limited protection against microbes penetrating the blood-brain barrier. This results in a neurological deficit and sometimes leads to high morbidity and mortality rates despite advanced therapies. For the last two decades, different studies have expanded our understanding of the molecular basis of human neuroinfectious diseases, especially concerning the contributions of mast cell interactions with other central nervous system compartments. Brain mast cells are multifunctional cells derived from the bone marrow and reside in the brain. Their proximity to blood vessels, their role as "first responders" their unique receptors systems and their ability to rapidly release pathogen responsive mediators enable them to exert a crucial defensive role in the host-defense system. This review describes key biological and physiological functions of mast cells, concerning their ability to recognize pathogens via various receptor systems, followed by a coordinated and selective mediator release upon specific interactions with pathogenic stimulating factors. The goal of this review is to direct attention to the possibilities for therapeutic applications of mast cells against bacterial and viral related infections. We also focus on opportunities for future research activating mast cells via adjuvants.
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Imunidade/efeitos dos fármacos , Mastócitos/metabolismo , Mastócitos/patologia , Animais , Infecções Bacterianas/patologia , Encéfalo/citologia , Encéfalo/metabolismo , Comunicação Celular , Sistema Nervoso Central/patologia , Humanos , Inflamação/patologia , Mastócitos/fisiologia , Viroses/patologiaRESUMO
Buprenorphine is an opioid drug used in the management of pain and the treatment opioid addiction. Like other opioids, it is believed that it achieves these effects by altering functional neurotransmitter pathways and the expression of important transcription factors; cyclic AMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) in the brain. However, there is a lack of scientific evidence to support these theories. This study investigated the pharmacodynamic effects of BUP administration by assessing neurotransmitter and molecular changes in the healthy rodent brain. Sprague-Dawley rats (150-200 g) were intranasally administered buprenorphine (0.3 mg/mL) and sacrificed at different time points: 0.25, 0.5, 1, 2, 4, 6, 8 and 24 h post drug administration. LC-MS was used to quantify BUP and neurotransmitters (GABA, GLUT, DA, NE and 5-HT) in the brain, while CREB and BDNF gene expression was determined using qPCR. Results showed that BUP reached a Cmax of 1.21 ± 0.0523 ng/mL after 2 h, with all neurotransmitters showing an increase in their concentration over time, with GABA, GLUT and NE reaching their maximum concentration after 8 h. DA and 5-HT reached their maximum concentrations at 1 h and 24 h, respectively post drug administration. Treatment with BUP resulted in significant upregulation in BDNF expression throughout the treatment period while CREB showed patterns of significant upregulation at 2 and 8 h, and downregulation at 1 and 6 h. This study contributes to the understanding of the pharmacodynamic effects of BUP in opioid addiction by proving that the drug significantly influences NT pathways that are implicated in opioid addiction.