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1.
Int J Mol Sci ; 24(24)2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38138972

RESUMEN

Despite the recent progress in the diagnosis of tuberculosis (TB), the chemotherapeutic management of TB continues to be challenging. Mycobacterium tuberculosis (Mtb), the etiological agent of TB, is classified as the 13th leading cause of death globally. In addition, 450,000 people were reported to develop multi-drug-resistant TB globally. The current project focuses on targeting methionine aminopeptidase (MetAP), an essential protein for the viability of Mtb. MetAP is a metalloprotease that catalyzes the excision of the N-terminal methionine (NME) during protein synthesis, allowing the enzyme to be an auspicious target for the development of novel therapeutic agents for the treatment of TB. Mtb possesses two MetAP1 isoforms, MtMetAP1a and MtMetAP1c, which are vital for Mtb viability and, hence, a promising chemotherapeutic target for Mtb therapy. In this study, we cloned and overexpressed recombinant MtMetAP1c. We investigated the in vitro inhibitory effect of the novel MetAP inhibitor, OJT008, on the cobalt ion- and nickel ion-activated MtMetAP1c, and the mechanism of action was elucidated through an in silico approach. The compound's potency against replicating and multi-drug-resistant (MDR) Mtb strains was also investigated. The induction of the overexpressed recombinant MtMetAP1c was optimized at 8 h with a final concentration of 1 mM Isopropyl ß-D-1-thiogalactopyranoside. The average yield from 1 L of Escherichia coli culture for MtMetAP1c was 4.65 mg. A preliminary MtMetAP1c metal dependency screen showed optimum activation with nickel and cobalt ions occurred at 100 µM. The half-maximal inhibitory concentration (IC50) values of OJT008 against MtMetAP1c activated with CoCl2 and NiCl2 were 11 µM and 40 µM, respectively. The in silico study showed OJT008 strongly binds to both metal-activated MtMetAP1c, as evidenced by strong molecular interactions and a higher binding score, thereby corroborating our result. This in silico study validated the pharmacophore's metal specificity. The potency of OJT008 against both active and MDR Mtb was <0.063 µg/mL. Our study reports OJT008 as an inhibitor of MtMetAP1c, which is potent at low micromolar concentrations against both active susceptible and MDR Mtb. These results suggest OJT008 is a potential lead compound for the development of novel small molecules for the therapeutic management of TB.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Níquel/farmacología , Aminopeptidasas/genética , Aminopeptidasas/química , Tuberculosis/microbiología , Metionil Aminopeptidasas , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Metales/farmacología , Cobalto/farmacología , Antituberculosos/química
2.
Am J Perinatol ; 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37230474

RESUMEN

OBJECTIVE: The aim of this study was to examine the relationship between obesity and risk of stillbirth among pregnant women with obesity in the United States, with a focus on racial and ethnic disparities. STUDY DESIGN: We conducted a retrospective cross-sectional analysis of birth and fetal data from the 2014 to 2019 National Vital Statistics System (N = 14,938,384 total births) to examine associations between maternal body mass index (BMI) and risk of stillbirth. Cox's proportional hazards regression model was used to compute adjusted hazard ratios (HR) as a measure of risk of stillbirth in relation to maternal BMI. RESULTS: The stillbirth rate was 6.70 per 1,000 births among women with prepregnancy obesity, while the stillbirth rate among women with a normal (nonobese) prepregnancy BMI was 3.85 per 1,000 births. The risk of stillbirth was greater among women with obesity compared with women without obesity (HR: 1.39; 95% confidence interval [CI]: 1.37-1.41). Compared with non-Hispanic (NH) Whites, women identifying as NH-other (HR: 1.66; 95% CI: 1.61-1.72) and NH-Black (HR: 1.31; 95% CI: 1.26-1.35) were at higher risk of stillbirth, while Hispanic women had a decreased likelihood of stillbirth (HR: 0.38; 95% CI: 0.37-0.40). CONCLUSION: Obesity is a modifiable risk factor for stillbirth. Public health awareness campaigns and strategies targeting weight management in women of reproductive age and racial/ethnic populations at highest risk for stillbirth, are needed. KEY POINTS: · Stillbirth rates differ by race and ethnicity.. · Risk of stillbirth was greatest among women with obesity.. · Stillbirth rates rise with ascending prepregnancy BMI..

3.
J Biomol Struct Dyn ; 41(7): 2992-3001, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35220925

RESUMEN

The outbreak of SARS-CoV-2 infections around the world has prompted scientists to explore different approaches to develop therapeutics against COVID-19. This study focused on investigating the mechanism of inhibition of clioquinol (CLQ) and its derivatives (7-bromo-5-chloro-8-hydroxyquinoline (CLBQ), 5, 7-Dichloro-8-hydroxyquinoline (CLCQ)) against the viral glycoprotein, and human angiotensin-converting enzyme-2 (hACE-2) involved in SARS-CoV-2 entry. The drugs were docked at the exopeptidase site of hACE-2 and receptor binding domain (RBD) sites of SARS-CoV-2 Sgp to calculate the binding affinity of the drugs. To understand and establish the inhibitory characteristics of the drugs, molecular dynamic (MD) simulation of the best fit docking complex performed. Evaluation of the binding energies of the drugs to hACE-2 after 100 ns MD simulations revealed CLQ to have the highest binding energy value of -40.4 kcal/mol close to MLN-7640 (-45.4 kcal/mol), and higher than the exhibited values for its derivatives: CLBQ (-34.5 kcal/mol) and CLCQ (-24.8 kcal/mol). This suggests that CLQ and CLBQ bind more strongly at the exopeptidase site than CLCQ. Nevertheless, the evaluation of binding affinity of the drugs to SARS-CoV-2 Sgp showed the drugs are weakly bound at the RBD site, with CLBQ, CLCQ, CLQ exhibiting relatively low energy values of -16.8 kcal/mol, -16.34 kcal/mol, -12.5 kcal/mol, respectively compared to the reference drug, Bisoxatin (BSX), with a value of -25.8 kcal/mol. The structural analysis further suggests decrease in systems stability and explain the mechanism of inhibition of clioquinol against SARS-CoV-2 as reported in previous in vitro study.Communicated by Ramaswamy H. Sarma.


Asunto(s)
COVID-19 , Clioquinol , Humanos , SARS-CoV-2 , Exopeptidasas , Angiotensinas
4.
Inform Med Unlocked ; 33: 101074, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36092780

RESUMEN

Several more infectious SARS-CoV-2 variants have emerged globally since SARS-CoV-2 pandemic and the discovery of the first D614G variant of SARS-CoV-2 spike proteins in 2020. Delta (B.1.617.2) and Omicron (B.1.1.529) variants have proven to be of major concern out of all the reported variants, considering their influence on the virus' transmissibility and severity. This study aimed at evaluating the impact of mutations on these two variants on stability and molecular interactions between the viral Spike protein and human angiotensin converting enzyme-2 (hACE-2). The spike proteins receptor binding domain (RBD) was docked with the hACE-2 using HADDOCK servers. To understand and establish the effects of the mutations on the structural stability and flexibility of the RBD-hACE-2 complex, molecular dynamic (MD) simulation of the docked complex was performed and evaluated. The findings from both molecular docking analysis and binding free energy showed that the Omicron (OM) variant has high receptiveness towards hACE-2 versus Delta variant (DT), thereby, responsible for its increase in transmission. The structural stability and flexibility evaluation of variants' systems showed that mutations on DT and OM variants disturbed the stability of either the spike protein or the RBD-hACE-2 complex, with DT variant having greater instability impact. This study, therefore, assumed this obvious instability observed in DT variant might be associated or responsible for the reported severity in DT variant disease over the OM variant disease. This study provides molecular insight into the effects of OM and DT variants on stability and interactions between SARS-CoV-2 protein and hACE-2.

5.
J Mol Graph Model ; 114: 108201, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35487151

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects the host cells through interaction of its spike protein with human angiotensin-converting enzyme 2 (hACE-2). High binding affinity between the viral spike protein and host cells hACE-2 receptor has been reported to enhance the viral infection. Thus, the disruption of this molecular interaction will lead to reduction in viral infectivity. This study, therefore, aimed to analyze the inhibitory potentials of two mucolytic drugs; Ambroxol hydrochlorides (AMB) and Bromhexine hydrochlorides (BHH), to serve as potent blockers of these molecular interactions and alters the binding affinity/efficiency between the proteins employing computational techniques. The study examined the effects of binding of each drug at the receptor binding domain (RBD) of the spike protein and the exopeptidase site of hACE-2 on the binding affinity (ΔGbind) and molecular interactions between the two proteins. Binding affinity revealed that the binding of the two drugs at the RBD-ACE-2 site does not alter the binding affinity and molecular interaction between the proteins. However, the binding of AMB (-56.931 kcal/mol) and BHH (-46.354 kcal/mol) at the exopeptidase site of hACE-2, significantly reduced the binding affinities between the proteins compared to the unbound, ACE-2-RBD complex (-64.856 kcal/mol). The result further showed the two compounds have good affinity at the hACE-2 site, inferring they might be potent inhibitors of hACE-2. Residue interaction networks analysis further revealed the binding of the two drugs at the exopeptidase site of hACE-2 reduced the number of interacting amino residues, subsequently leading to loss of interactions between the two proteins, with BHH showing better reduction in the molecular interaction and binding affinity than AMB. The result of the structural analyses additionally, revealed that the binding of the drugs considerably influences the dynamic of the complexes when compared to the unbound complex. The findings from this study suggest the binding of the two drugs at the exopeptidase site reduces the binding effectiveness of the proteins than their binding at the RBD site, and consequently might inhibit viral attachment and entry.


Asunto(s)
Ambroxol , Bromhexina , Tratamiento Farmacológico de COVID-19 , Enzima Convertidora de Angiotensina 2 , Angiotensinas/metabolismo , Humanos , Unión Proteica , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/química
6.
Int J MCH AIDS ; 10(1): 109-112, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33868776

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent for the coronavirus disease 2019 (COVID-19) pandemic, highlighted and compounded problems while posing new challenges for the pregnant population. Although individual organizations have provided disparate information, guidance, and updates on managing the pregnant population during the current COVID-19 pandemic, it is important to develop a collective model that highlights all the best practices needed to protect the pregnant population during the pandemic. To establish a standard for ensuring safety during the pandemic, we present a framework that describes best practices for the management of the pregnant population during the ongoing COVID-19 pandemic.

7.
Heliyon ; 7(3): e06426, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33732940

RESUMEN

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiological agent for coronavirus disease 2019 (COVID-19), has resulted in an ongoing pandemic. Presently, there are no clinically approved drugs for COVID-19. Hence, there is an urgent need to accelerate the development of effective antivirals. Herein, we discovered Clioquinol (5-chloro-7-iodo-8-quinolinol (CLQ)), a Food and Drug Administration (FDA) approved drug, and two of its analogues (7-bromo-5-chloro-8-hydroxyquinoline (CLBQ14); and 5, 7-Dichloro-8-hydroxyquinoline (CLCQ)) as potent inhibitors of SARS-CoV-2 infection-induced cytopathic effect in vitro. In addition, all three compounds showed potent anti-exopeptidase activity against recombinant human angiotensin-converting enzyme 2 (rhACE2) and inhibited the binding of rhACE2 with SARS-CoV-2 Spike (RBD) protein. CLQ displayed the highest potency in the low micromolar range, with its antiviral activity showing a strong correlation with inhibition of rhACE2 and rhACE2-RBD interaction. Altogether, our findings provide a new mode of action and molecular target for CLQ and validates this pharmacophore as a promising lead series for the clinical development of potential therapeutics for COVID-19.

8.
Int J MCH AIDS ; 10(1): 66-69, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33442493

RESUMEN

Currently, there is an insufficient representation of racial/ethnic minority groups in the maternal and child health (MCH) workforce. A student-run outreach organization, the Global Alliance for Maternal and Child Health (GLAM), seeks to address this disparity by increasing the representation of racial/ethnic minority groups in MCH workforce. Founded by students at Texas Southern University in Houston, Texas, United States, GLAM, seeks to establish productive alliances and create programs that would help improve the well-being of mothers, infants, and children locally, nationally, and internationally by engaging an active cadre of students passionate about MCH. Through community outreach and global engagement using evidence-based strategies, GLAM is committed to the elimination of health disparities plaguing the MCH population.

9.
J Racial Ethn Health Disparities ; 8(3): 670-677, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32754847

RESUMEN

BACKGROUND: Preeclampsia and HIV account for a significant proportion of the global burden of disease and pose severe maternal-fetal risks. There is a dearth of literature regarding racial/ethnic disparities in preeclampsia associated with HIV/AIDS in the US. METHODS: We retrospectively analyzed data from the National Inpatient Sample (NIS) database from 2002 to 2015 on a cohort of hospitalized pregnant women with or without preeclampsia and HIV. Joinpoint regression models were used to identify trends in the rates of preeclampsia among pregnant women living with or without HIV, stratified by race/ethnicity over the study period. We also assessed the association between preeclampsia and various socio-demographic factors. RESULTS: We analyzed over 60 million pregnancy-related hospitalizations, of which 3665 had diagnoses of preeclampsia and HIV, corresponding to a rate of 0.61 per 10,000. There was an increasing trend in the diagnosis of preeclampsia among hospitalized, pregnant women without HIV across each racial/ethnic category. The highest prevalence of preeclampsia was among non-Hispanic (NH) Blacks, regardless of HIV status. CONCLUSION: The increase in rates of pre-eclampsia between 2002 and 2015 was mostly noted among pregnant women without HIV. Regardless of HIV status, NH-Blacks experienced the highest discharge prevalence of preeclampsia.


Asunto(s)
Etnicidad/estadística & datos numéricos , Infecciones por VIH/etnología , Disparidades en el Estado de Salud , Preeclampsia/etnología , Complicaciones Infecciosas del Embarazo/etnología , Grupos Raciales/estadística & datos numéricos , Adolescente , Adulto , Bases de Datos Factuales , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Estudios Retrospectivos , Estados Unidos/epidemiología , Adulto Joven
10.
J Racial Ethn Health Disparities ; 8(1): 24-32, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32378158

RESUMEN

OBJECTIVE: The purpose of this study was to determine whether cervical cancer is a risk factor for early mortality among women with HIV and whether racial/ethnic disparity predicted in-hospital death among women living with HIV and diagnosed with cervical cancer. METHODS: We conducted a population-based study using the National Inpatient Sample (NIS) database comprising hospitalized HIV-positive women with or without cervical cancer diagnosis, from 2003 through 2015. We compared trends in the rates of cervical cancer, in-hospital death, and years of potential life lost (YPLL) by race/ethnicity. RESULTS: We identified 2,613,696 women with HIV, and among them, 5398 had cervical cancer. The prevalence of cervical cancer (per 10,000) was 9.3 for NH-Whites, 30.9 among NH-Blacks, and 30.2 for Hispanics. Rates of cervical cancer over time diminished significantly only among NH-Whites (average annual percent change (AAPC), - 5.8 (- 9.7, - 1.8)), and YPLL in women with cervical cancer decreased significantly only in NH-Whites (AAPC, - 6.2 (- 10.1, - 2.0)). Cervical cancer was associated with increased odds of in-hospital death overall (OR 2.24 (1.59-3.15)) and among NH-Blacks (OR 2.03 (1.30-3.18)) only. CONCLUSIONS: NH-Blacks and Hispanics with HIV remain at increased risk for concurrent diagnosis of cervical cancer compared with NH-Whites. Moreover, NH-Black women with HIV and cervical cancer are at greatest risk for in-hospital death. The findings emphasize the need for a more robust prevention strategy among minority women to reduce the high burden of HIV/cervical cancer and related mortality.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Infecciones por VIH/etnología , Disparidades en el Estado de Salud , Hispánicos o Latinos/estadística & datos numéricos , Mortalidad Hospitalaria/etnología , Neoplasias del Cuello Uterino/etnología , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Bases de Datos Factuales , Femenino , Humanos , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos/epidemiología , Población Blanca/estadística & datos numéricos , Adulto Joven
11.
bioRxiv ; 2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32995775

RESUMEN

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), enters the host cells through two main pathways, both involving key interactions between viral envelope-anchored spike glycoprotein of the novel coronavirus and the host receptor, angiotensin-converting enzyme 2 (ACE2). To date, SARS-CoV-2 has infected up to 26 million people worldwide; yet, there is no clinically approved drug or vaccine available. Therefore, a rapid and coordinated effort to re-purpose clinically approved drugs that prevent or disrupt these critical entry pathways of SARS-CoV-2 spike glycoprotein interaction with human ACE2, could potentially accelerate the identification and clinical advancement of prophylactic and/or treatment options against COVID-19, thus providing possible countermeasures against viral entry, pathogenesis and survival. Herein, we discovered that Ambroxol hydrochloride (AMB), and its progenitor, Bromhexine hydrochloride (BHH), both clinically approved drugs are potent effective modulators of the key interaction between the receptor binding domain (RBD) of SARS-CoV-2 spike protein and human ACE2. We also found that both compounds inhibited SARS-CoV-2 infection-induced cytopathic effect at micromolar concentrations. Therefore, in addition to the known TMPRSS2 activity of BHH; we report for the first time that the BHH and AMB pharmacophore has the capacity to target and modulate yet another key protein-protein interaction essential for the two known SARS-CoV-2 entry pathways into host cells. Altogether, the potent efficacy, excellent safety and pharmacologic profile of both drugs along with their affordability and availability, makes them promising candidates for drug repurposing as possible prophylactic and/or treatment options against SARS-CoV-2 infection.

12.
bioRxiv ; 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32817951

RESUMEN

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiological agent for coronavirus disease 2019 (COVID-19), has emerged as an ongoing global pandemic. Presently, there are no clinically approved vaccines nor drugs for COVID-19. Hence, there is an urgent need to accelerate the development of effective antivirals. Here in, we discovered Clioquinol (5-chloro-7-iodo-8-quinolinol (CLQ)), a FDA approved drug and two of its analogues (7-bromo-5-chloro-8-hydroxyquinoline (CLBQ14); and 5, 7-Dichloro-8-hydroxyquinoline (CLCQ)) as potent inhibitors of SARS-CoV-2 infection induced cytopathic effect in vitro . In addition, all three compounds showed potent anti-exopeptidase activity against recombinant human angiotensin converting enzyme 2 (rhACE2) and inhibited the binding of rhACE2 with SARS-CoV-2 Spike (RBD) protein. CLQ displayed the highest potency in the low micromolar range, with its antiviral activity showing strong correlation with inhibition of rhACE2 and rhACE2-RBD interaction. Altogether, our findings provide a new mode of action and molecular target for CLQ and validates this pharmacophore as a promising lead series for clinical development of potential therapeutics for COVID-19.

13.
Braz. j. pharm. sci ; 46(3): 531-537, July-Sept. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-564920

RESUMEN

A study was conducted on the packing and cohesive properties of chloroquine phosphate in binary mixtures with lactose and dicalcium phosphate powders. The maximum volume reduction due to packing as expressed by the Kawakita constant, a, and the angle of internal flow, θ, were the assessment parameters. The individual powders were characterized for their particle size and shape using an optical microscope. Binary mixtures of various proportions of chloroquine phosphate with lactose and dicalcium phosphate powders were prepared. The bulk and tapped densities, angles of repose and internal flow, as well as compressibility index of the materials were determined using appropriate parameters. The calculated and determined values of maximum volume reduction for the binary mixtures were found to differ significantly (P< 0.05), with the Kawakita plot being more reliable in determining the packing properties. Diluent type was found to influence the flow properties of the mixtures, with dicalcium phosphate giving predictable results while mixtures containing lactose were anomalous with respect to flow. The characterization of the packing and cohesive properties of the binary mixtures of chloroquine with lactose and dicalcium phosphate would be useful in the production of powders, tablets, capsules and other drug delivery systems containing these powders with desirable and predictable flow properties.


Realizou-se estudo das propriedades de empacotamento e de coesão do fosfato de cloroquina em misturas binárias com lactose e fosfato dicálcico em pó. O volume máximo de redução devido ao empacotamento, segundo expresso pela constante de Kawakita, a, e o ângulo de fluxo interno, θ, foram os parâmetros de avaliação. Os pós individuais foram caracterizados por seu tamanho e forma de partículas, utilizando microscópio óptico. Prepararam-se misturas binárias de várias proporções de fosfato de cloroquine e lactose e fosfato dicálcico em pó. As densidades de bulk and tapped, os ângulos de repouso e de fluxo interno e o índice de compressibilidade dos materiais foram determinados utilizando-se parâmetros apropriados. Os valores calculados e determinados do volume máximo de redução para as misturas binárias mostraram-se significativamente diferentes (P< 0,05), sendo o traçado de Kawakita mais confiável na determinação das propriedades de empacotamento. O tipo de diluente influenciou as propriedades de fluxo das misturas com fosfato dicálcico, dando resultados previsíveis, enquanto as misturas contendo lactose mostraram-se anômalas com relação ao fluxo. A caracterização das propriedades de empacotamento e de coesão das misturas binárias de cloroquina com lactose e fosfato dicálcico seria útil na produção de pós, comprimidos, cápsulas e outros sistemas de liberação de fármacos contendo esses pós com propriedade de fluxo desejada e previsível.


Asunto(s)
Compuestos Químicos , Cloroquina , Calcio/química , Lactosa , Fosfatos , Embalaje de Productos/métodos
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