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1.
Bioinorg Chem Appl ; 2022: 6835625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212986

RESUMO

Currently, new advancements in the area of nanotechnology opened up new prospects in the field of medicine that could provide us with a solution for numerous medical complications. Although a several varieties of nanoparticles is being explored to be used as nanomedicines, cerium oxide nanoparticles (CeO2 NPs) are the most attractive due to their biocompatibility and their switchable oxidation state (+3 and +4) or in other words the ability to act as prooxidant and antioxidant depending on the pH condition. Green synthesis of nanoparticles is preferred to make it more economical, eco-friendly, and less toxic. The aim of our study here is to formulate the CeO2 NPs (CeO2 NPs) using Morinda citrifolia (Noni) leaf extract and study its optical, structural, antibacterial, and anticancer abilities. Their optical and structural characterization was accomplished by employing X-ray diffractography (XRD), TEM, EDAX, FTIR, UV-vis, and photoluminescence assays. Our CeO2 NPs expressed strong antibacterial effects against Gram-positive S. aureus and S. pneumonia in addition to Gram-negative E. coli and K. pneumonia when compared with amoxicillin. The anticancer properties of the green synthesized CeO2 NPs against human acute lymphoblastic leukemia (ALL) MOLT-4 cells were further explored by the meticulous study of their ability to diminish cancer cell viability (cytotoxicity), accelerate apoptosis, escalate intracellular reactive oxygen species (ROS) accumulation, decline the mitochondria membrane potential (MMP) level, modify the cell adhesion, and shoot up the activation of proapoptotic markers, caspase-3, -8, and -9, in the tumor cells. Altogether, the outcomes demonstrated that our green synthesized CeO2 NPs are an excellent candidate for alternative cancer therapy.

2.
Nanomaterials (Basel) ; 11(12)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34947512

RESUMO

Cancer progresses through a distinctive reprogramming of metabolic pathways directed by genetic and epigenetic modifications. The hardwired changes induced by genetic mutations are resilient, while epigenetic modifications are softwired and more vulnerable to therapeutic intervention. Colon cancer is no different. This gives us the need to explore the mechanism as an attractive therapeutic target to combat colon cancer cells. We have previously established the enhanced therapeutic efficacy of a newly formulated camptothecin encapsulated in ß-cyclodextrin-EDTA-Fe3O4 nanoparticles (CPT-CEF) in colon cancer cells. We furthered this study by carrying out RNA sequencing (RNA-seq) to underscore specific regulatory signatures in the CPT-CEF treated versus untreated HT29 cells. In the study, we identified 95 upregulated and 146 downregulated genes spanning cellular components and molecular and metabolic functions. We carried out extensive bioinformatics analysis to harness genes potentially involved in epigenetic modulation as either the cause or effect of metabolic rewiring exerted by CPT-CEF. Significant downregulation of 13 genes involved in the epigenetic modulation and 40 genes from core metabolism was identified. Three genes, namely, DNMT-1, POLE3, and PKM-2, were identified as the regulatory overlap between epigenetic drivers and metabolic reprogramming in HT29 cells. Based on our results, we propose a possible mechanism that intercepts the two functional axes, namely epigenetic control, and metabolic modulation via CPT-CEF in colon cancer cells, which could skew cancer-induced metabolic deregulation towards metabolic repair. Thus, the study provides avenues for further validation of transcriptomic changes affected by these deregulated genes at epigenetic level, and ultimately may be harnessed as targets for regenerating normal metabolism in colon cancer with better treatment potential, thereby providing new avenues for colon cancer therapy.

3.
Medicina (Kaunas) ; 57(8)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34441045

RESUMO

Biofilms comprising aggregates of microorganisms or multicellular communities have been a major issue as they cause resistance against antimicrobial agents and biofouling. To date, numerous biofilm-forming microorganisms have been identified, which have been shown to result in major effects including biofouling and biofilm-related infections. Quorum sensing (which describes the cell communication within biofilms) plays a vital role in the regulation of biofilm formation and its virulence. As such, elucidating the various mechanisms responsible for biofilm resistance (including quorum sensing) will assist in developing strategies to inhibit and control the formation of biofilms in nature. Employing biological control measures (such as the use of bioactive compounds) in targeting biofilms is of great interest since they naturally possess antimicrobial activity among other favorable attributes and can also possibly act as potent antibiofilm agents. As an effort to re-establish the current notion and understanding of biofilms, the present review discuss the stages involved in biofilm formation, the factors contributing to its development, the effects of biofilms in various industries, and the use of various bioactive compounds and their strategies in biofilm inhibition.


Assuntos
Biofilmes , Percepção de Quorum , Antibacterianos/farmacologia
4.
Front Cell Neurosci ; 12: 190, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30108483

RESUMO

Retinal degeneration is a prominent feature in ocular disorders. In exploring possible treatments, Mesenchymal Stem Cells (MSCs) have been recognized to yield therapeutic role for retinal degenerative diseases. Studies have also displayed that erythropoietin (EPO) administration into degenerative retina models confers significant neuroprotective actions in limiting pathological cell death. In this study, we aimed to use MSCs to deliver EPO and to evaluate the ability of EPO to rescue retinal neurons from dying upon reactive oxidative stress induction. We derived human MSCs from Wharton's jelly (hWJMSCs) of the umbilical cord and cells were transduced with lentivirus particles encoding EPO and a reporter gene of green fluorescent protein (GFP). The supernatants of both transduced and non-transduced cells were collected and used as a pre-conditioning medium for Y79 retinoblastoma cells (retinal neuron cell line) following exposure to glutamate induction. Retinal cells exposed to glutamate showed reduced mitochondrial depolarization and enhanced improvement in cell viability when incubated with pre-conditioned media of transduced cells. Our results established a proof-of-concept that MSCs could be used as a candidate for the delivery of EPO therapeutic gene in the treatment of retinal degenerations.

5.
Food Chem Toxicol ; 118: 953-962, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29883785

RESUMO

Flowers of Tabernaemontana divaricata (L.) R. Br., (Apocynaceae) are used in traditional medicine for analgesic property. The present study was performed to isolate the active principles and investigate the mechanisms involved in the anti-nociception caused by T. divaricata flower methanolic extract (TDFME). The extract in the doses of 125, 250 and 500 mg/kg, p.o was subjected to various assays in acetic acid induced abdominal writhing and formalin induced paw licking test models. Naloxone, L-Arginine, Glibenclamide and Glutamate were used as inducers while Morphine, L-NAME, Methylene blue and Aspirin served as standard drugs. The phytochemical analysis led to the isolation of three indole alkaloids namely Voacangine, Catharanthine and O-acetyl Vallesamine. The anti-nociception produced by TDFME was attenuated significantly (p< 0.001) by the intra-peritoneal pretreatment of naloxone, L-Arginine and glibenclamide. The nociception produced by glutamate was inhibited by TDFME. TDFME also enhanced the antinociceptive activity of L-NAME when given in combination. However TDFME co-administration did not produce significant results with methylene blue indicating lack of cGMP involvement. These results indicate that TDFME produces anti-nociception action mediated by opioid, nitric oxide, K+-ATP and glutamate mechanisms and the effect is largely related to the indole alkaloids.


Assuntos
Analgésicos/farmacologia , Flores/química , Alcaloides Indólicos/farmacologia , Metanol/química , Extratos Vegetais/farmacologia , Tabernaemontana/química , Animais , Relação Dose-Resposta a Droga , Masculino , Camundongos
6.
J Photochem Photobiol B ; 183: 127-132, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29704860

RESUMO

BACKGROUND: Retinal degeneration is a condition ensued by various ocular disorders such as artery occlusion, diabetic retinopathy, retrolental fibroplasia and retinitis pigmentosa which cause abnormal loss of photoreceptor cells and lead to eventual vision impairment. No efficient treatment has yet been found, however, the use of stem cell therapy such as bone marrow and embryonic stem cells has opened a new treatment modality for retinal degenerative diseases. The major goal of this study is to analyze the potential of endothelial progenitor cells derived from bone marrow to differentiate into retinal neural cells for regenerative medicine purposes. METHODS: In this study, endothelial progenitor cells were induced in-vitro with photoreceptor growth factor (taurine) for 21 days. Subsequently, the morphology and gene expression of CRX and RHO of the photoreceptors-induced EPCs were examined through immunostaining assay. FINDINGS: The results indicated that the induced endothelial progenitor cells demonstrated positive gene expression of CRX and RHO. Our findings suggested that EPC cells may have a high advantage in cell replacement therapy for treating eye disease, in addition to other neural diseases, and may be a suitable cell source in regenerative medicine for eye disorders.


Assuntos
Proteínas de Homeodomínio/metabolismo , Rodopsina/metabolismo , Transativadores/metabolismo , Antígeno AC133/metabolismo , Animais , Antígenos CD34/metabolismo , Células da Medula Óssea/citologia , Diferenciação Celular , Linhagem Celular , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/metabolismo , Expressão Gênica , Proteínas de Homeodomínio/genética , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-kit/metabolismo , Rodopsina/genética , Transativadores/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
7.
Tuberculosis (Edinb) ; 107: 38-47, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29050770

RESUMO

Mycobacterium tuberculosis has a remarkable ability of long-term persistence despite vigorous host immunity and prolonged therapy. The bacteria persist in secure niches such as the mesenchymal stem cells in the bone marrow and reactivate the disease, leading to therapeutic failure. Many bacterial cells can remain latent within a diseased tissue so that their genetic material can be incorporated into the genetic material of the host tissue. This incorporated genetic material reproduces in a manner similar to that of cellular DNA. After the cell division, the incorporated gene is reproduced normally and distributed proportionately between the two progeny. This inherent adoption of long-term persistence and incorporating the bacterial genetic material into that of the host tissue remains and is considered imperative for microbial advancement and chemotherapeutic resistance; moreover, new evidence indicates that the bacteria might pass on genetic material to the host DNA sequence. Several studies focused on the survival mechanism of M. tuberculosis in the host immune system with the aim of helping the efforts to discover new drugs and vaccines against tuberculosis. This review explored the mechanisms through which this bacterium affects the expression of human genes. The first part of the review summarizes the current knowledge about the interactions between microbes and host microenvironment, with special reference to the M. tuberculosis neglected persistence in immune cells and stem cells. Then, we focused on how bacteria can affect human genes and their expression. Furthermore, we analyzed the literature base on the process of cell death during tuberculosis infection, giving particular emphasis to gene methylation as an inherited process in the neutralization of possibly injurious gene components in the genome. The final section discusses recent advances related to the M. tuberculosis interaction with host epigenetic circuitry.


Assuntos
Replicação do DNA , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Tuberculose Latente/genética , Tuberculose Latente/microbiologia , Mycobacterium tuberculosis/genética , Antituberculosos/uso terapêutico , Morte Celular , Metilação de DNA , DNA Bacteriano/biossíntese , Farmacorresistência Bacteriana/genética , Epigênese Genética , Interações Hospedeiro-Patógeno , Humanos , Tuberculose Latente/tratamento farmacológico , Tuberculose Latente/imunologia , Viabilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/patogenicidade , Células-Tronco/imunologia , Células-Tronco/microbiologia
8.
Acta Trop ; 176: 433-439, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28941729

RESUMO

Leptospirosis is a widespread zoonotic disease caused by pathogenic Leptospira species (Leptospiraceae). LipL32 is an abundant lipoprotein from the outer membrane proteins (OMPs) group, highly conserved among pathogenic and intermediate Leptospira species. Several studies used LipL32 as a specific gene to identify the presence of leptospires. This research was aimed to study the characteristics of LipL32 protein gene code, to fill the knowledge gap concerning the most appropriate gene that can be used as antigen to detect the Leptospira. Here, we investigated the features of LipL32 in fourteen Leptospira pathogenic strains based on comparative analyses of their primary, secondary structures and 3D modeling using a bioinformatics approach. Furthermore, the physicochemical properties of LipL32 in different strains were studied, shedding light on the identity of signal peptides, as well as on the secondary and tertiary structure of the LipL32 protein, supported by 3D modelling assays. The results showed that the LipL32 gene was present in all the fourteen pathogenic Leptospira strains used in this study, with limited diversity in terms of sequence conservation, hydrophobic group, hydrophilic group and number of turns (random coil). Overall, these results add basic knowledge to the characteristics of LipL32 protein, contributing to the identification of potential antigen candidates in future research, in order to ensure prompt and reliable detection of pathogenic Leptospira species.


Assuntos
Antígenos de Bactérias/química , Proteínas da Membrana Bacteriana Externa/química , Leptospira/imunologia , Leptospirose/imunologia , Lipoproteínas/química , Modelos Moleculares , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Biologia Computacional , Leptospira/genética , Lipoproteínas/imunologia
9.
Acta Trop ; 176: 206-223, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28823908

RESUMO

Immuno-pathogenesis of leptospirosis can be recounted well by following its trail path from entry to exit, while inducing disastrous damages in various tissues of the host. Dysregulated, inappropriate and excessive immune responses are unanimously blamed in fatal leptospirosis. The inherent abilities of the pathogen and inabilities of the host were debated targeting the severity of the disease. Hemorrhagic manifestation through various mechanisms leading to a fatal end is observed when this disease is unattended. The similar vascular destructions and hemorrhage manifestations are noted in infections with different microbes in endemic areas. The simultaneous infection in a host with more than one pathogen or parasite is referred as the coinfection. Notably, common endemic infections such as leptospirosis, dengue, chikungunya, and malaria, harbor favorable environments to flourish in similar climates, which is aggregated with stagnated water and aggravated with the poor personal and environmental hygiene of the inhabitants. These factors aid the spread of pathogens and parasites to humans and potential vectors, eventually leading to outbreaks of public health relevance. Malaria, dengue and chikungunya need mosquitoes as vectors, in contrast with leptospirosis, which directly invades human, although the environmental bacterial load is maintained through other mammals, such as rodents. The more complicating issue is that infections by different pathogens exhibiting similar symptoms but require different treatment management. The current review explores different pathogens expressing specific surface proteins and their ability to bind with array of host proteins with or without immune response to enter into the host tissues and their ability to evade the host immune responses to invade and their affinity to certain tissues leading to the common squeal of hemorrhage. Furthermore, at the host level, the increased susceptibility and inability of the host to arrest the pathogens' and parasites' spread in different tissues, various cytokines accumulated to eradicate the microorganisms and their cellular interactions, the antibody dependent defense and the susceptibility of individual organs bringing the manifestation of the diseases were explored. Lastly, we provided a discussion on the immune trail path of pathogenesis from entry to exit to narrate the similarities and dissimilarities among various hemorrhagic fevers mentioned above, in order to outline future possibilities of prevention, diagnosis, and treatment of coinfections, with special reference to endemic areas.


Assuntos
Febre de Chikungunya/epidemiologia , Dengue/epidemiologia , Leptospirose/epidemiologia , Malária/epidemiologia , Animais , Carga Bacteriana , Febre de Chikungunya/imunologia , Febre de Chikungunya/transmissão , Clima , Coinfecção , Culicidae/microbiologia , Dengue/imunologia , Dengue/transmissão , Surtos de Doenças , Humanos , Leptospirose/imunologia , Leptospirose/transmissão , Malária/imunologia , Malária/transmissão , Saúde Pública
10.
Acta Trop ; 171: 213-219, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28427958

RESUMO

Dengue virus (DENV) has emerged as a major economic concern in developing countries, with 2.5 billion people believed to be at risk. Vascular endothelial cells (ECs) lining the circulatory system from heart to end vessels perform crucial functions in the human body, by aiding gas exchange in lungs, gaseous, nutritional and its waste exchange in all tissues, including the blood brain barrier, filtration of fluid in the glomeruli, neutrophil recruitment, hormone trafficking, as well as maintenance of blood vessel tone and hemostasis. These functions can be deregulated during DENV infection. In this study, BALB/c mice infected with DENV serotype 2 were analyzed histologically for changes in major blood vessels in response to DENV infection. In the uninfected mouse model, blood vessels showed normal architecture with intact endothelial monolayer, tunica media, and tunica adventitia. In the infected mouse model, DENV distorted the endothelium lining and disturbed the smooth muscle, elastic laminae and their supporting tissues causing vascular structural disarrangement. This may explain the severe pathological illness in DENV-infected individuals. The overall DENV-induced damages on the endothelial and it's supporting tissues and the dysregulated immune reactions initiated by the host were discussed.


Assuntos
Vírus da Dengue/classificação , Dengue/patologia , Dengue/virologia , Células Endoteliais/patologia , Animais , Células Endoteliais/virologia , Camundongos , Camundongos Endogâmicos BALB C , Sorogrupo
11.
Tissue Cell ; 49(1): 86-94, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28034555

RESUMO

In this research, we characterized the histopathological impact of dengue virus (serotype DENV-2) infection in livers of BALB/c mice. The mice were infected with different doses of DENV-2 via intraperitoneal injection and liver tissues were processed for histological analyses and variation was documented. In the BALB/c mouse model, typical liver tissues showed regular hepatocyte architecture, with normal endothelial cells surrounding sinusoid capillary. Based on histopathological observations, the liver sections of BALB/c mice infected by DENV-2 exhibited a loss of cell integrity, with a widening of the sinusoidal spaces. There were marked increases in the infiltration of mononuclear cells. The areas of hemorrhage and micro- and macrovesicular steatosis were noted. Necrosis and apoptosis were abundantly present. The hallmark of viral infection, i.e., cytopathic effects, included intracellular edema and vacuole formation, cumulatively led to sinusoidal and lobular collapse in the liver. The histopathological studies on autopsy specimens of fatal human DENV cases are important to shed light on tissue damage for preventive and treatment modalities, in order to manage future DENV infections. In this framework, the method present here on BALB/c mouse model may be used to study not only the effects of infections by other DENV serotypes, but also to investigate the effects of novel drugs, such as recently developed nano-formulations, and the relative recovery ability with intact immune functions of host.


Assuntos
Vírus da Dengue/patogenicidade , Dengue/virologia , Hepatócitos/virologia , Fígado/patologia , Animais , Dengue/patologia , Modelos Animais de Doenças , Hepatócitos/patologia , Humanos , Fígado/virologia , Camundongos , Sorogrupo
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