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Influenza A virus (IAV) is a highly contagious respiratory pathogen that significantly threatens global health by causing seasonal epidemics and occasional, unpredictable pandemics. To identify new compounds with therapeutic potential against IAV, we designed and synthesized a series of 4'-morpholinodiazenyl chalcones using the molecular hybridization method, performed a high-content screen against IAV, and found that (E)-1-{4-[(E)-morpholinodiazenyl]phenyl}-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (MC-22) completely neutralized IAV infection. While MC-22 allowed IAV to successfully internalize into the cell and fuse at the acidic late endosomes, it prevented viral capsid uncoating and genome release. Since IAV majorly utilizes clathrin-mediated endocytosis (CME) for cellular entry, we examined whether MC-22 had any effect on CME, using nonviral cargoes that enter cells via clathrin-dependent or -independent pathways. Although MC-22 showed no effect on the uptake of choleratoxin B, a cargo that enters cells majorly via the clathrin-independent pathway, it significantly attenuated the clathrin-dependent internalization of both epidermal growth factor and transferrin. Cell biological analyses revealed a marked increase in the size of early endosomes upon MC-22 treatment, indicating an endosomal trafficking/maturation defect. This study reports the identification of MC-22 as a novel CME-targeting, highly potent IAV entry inhibitor, which is expected to neutralize a broad spectrum of viruses that enter the host cells via CME.
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Antivirais , Clatrina , Vírus da Influenza A , Humanos , Vírus da Influenza A/efeitos dos fármacos , Clatrina/metabolismo , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Endocitose/efeitos dos fármacos , Animais , Chalconas/farmacologia , Chalconas/síntese química , Chalconas/química , Desenvelopamento do Vírus/efeitos dos fármacos , Cães , Células Madin Darby de Rim Canino , Internalização do Vírus/efeitos dos fármacos , Morfolinas/farmacologia , Morfolinas/síntese química , Morfolinas/química , Células A549 , Relação Estrutura-AtividadeRESUMO
The frequent emergence of pathogenic viruses with pandemic potential has posed a significant threat to human health and economy, despite enormous advances in our understanding of infection mechanisms and devising countermeasures through developing various prophylactic and therapeutic strategies. The recent coronavirus disease (COVID-19) pandemic has re-emphasised the importance of rigorous research on virus infection mechanisms and highlighted the need for our preparedness for potential pandemics. Although viruses cannot self-replicate, they tap into host cell factors and processes for their entry, propagation and dissemination. Upon entering the host cells, viruses ingeniously utilise the innate biological functions of the host cell to replicate themselves and maintain their existence in the hosts. Influenza A virus (IAV), which has a negative-sense, single-stranded RNA as its genome, is no exception. IAVs are enveloped viruses with a lipid bilayer derived from the host cell membrane and have a surface covered with the spike glycoprotein haemagglutinin (HA) and neuraminidase (NA). Viral genome is surrounded by an M1 shell, forming a "capsid" in the virus particle. IAV particles use HA to recognise sialic acids on the cell surface of lung epithelial cells for their attachment. After attachment to the cell surface, IAV particles are endocytosed and sorted into the early endosomes. Subsequently, as the early endosomes mature into late endosomes, the endosomal lumen becomes acidified, and the low pH of the late endosomes induces conformational reaggangements in the HA to initiate fusion between the endosomal and viral membranes. Upon fusion, the viral capsid disintegrates and the viral ribonucleoprotein (vRNP) complexes containing the viral genome are released into the cytosol. The process of viral capsid disintegration is called "uncoating". After successful uncoating, the vRNPs are imported into the nucleus by importin α/ß (IMP α/ß), where viral replication and transcription take place and the new vRNPs are assembled. Recently, we have biochemically elucidated the molecular mechanisms of the processes of viral capsid uncoating subsequent viral genome dissociation. In this chapter, we present the molecular details of the viral uncoating process.
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Vírus da Influenza A , Humanos , Vírus da Influenza A/genética , Replicação Viral , Capsídeo , Proteínas do Capsídeo , VírionRESUMO
In this study, nanocomposite film was fabricated using cellulose nanocrystals (CNCs) as nanofiller in a polymer matrix of polyvinyl alcohol (PVA) and gum tragacanth (GT) via solution casting. CNCs were extracted from sugarcane bagasse using a steam explosion technique followed by acid hydrolysis. Initial analysis of CNCs by transmission electron microscopy (TEM) showed nanosized particles of 104 nm in length and 7 nm in width. Physical and chemical characteristics of neat PVA, PVA/GT, and PVA/GT/CNC films with varying concentrations of CNCs (from 2% to 10%) were analyzed by the scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectrometry, mechanical test, and swelling test. The SEM analysis showed cluster formation of CNCs in the polymer matrix at high concentration. The developed films were transparent. FTIR spectrometry analysis confirmed the chemical functional groups of the various components in the film. The presence of GT and CNCs in the polymer matrix improved the characteristics of films as evident in the prolonged stability for 7 days and increased mechanical properties. The highest elastic modulus of 1526.11 ± 31.86 MPa and tensile strength of 80.39 MPa were recorded in PVA/GT/CNC2 film. The swelling ability, however, decreased from 260% to 230%. Cytotoxicity analysis of the PVA/GT/CNC film showed that it is nontoxic to mouse fibroblast cells L929 with 95% cell viability. Films loaded with betel leaf extract exhibited excellent antibacterial activities against Staphylococcus aureus DMST 8840 and Pseudomonas aeruginosa TISTR 781 with 28.20 ± 0.84 mm and 23.60 ± 0.55 mm inhibition zones, respectively. These results demonstrate that PVA/GT/CNC loaded with the betel leaf extract could act as promising and versatile wound dressings to protect the wound surface from infection and dehydration.
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Rapid evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza A virus (IAV) poses enormous challenge in the development of broad-spectrum antivirals that are effective against the existing and emerging viral strains. Virus entry through endocytosis represents an attractive target for drug development, as inhibition of this early infection step should block downstream infection processes, and potentially inhibit viruses sharing the same entry route. In this study, we report the identification of 1,3-diphenylurea (DPU) derivatives (DPUDs) as a new class of endocytosis inhibitors, which broadly restricted entry and replication of several SARS-CoV-2 and IAV strains. Importantly, the DPUDs did not induce any significant cytotoxicity at concentrations effective against the viral infections. Examining the uptake of cargoes specific to different endocytic pathways, we found that DPUDs majorly affected clathrin-mediated endocytosis, which both SARS-CoV-2 and IAV utilize for cellular entry. In the DPUD-treated cells, although virus binding on the cell surface was unaffected, internalization of both the viruses was drastically reduced. Since compounds similar to the DPUDs were previously reported to transport anions including chloride (Cl-) across lipid membrane and since intracellular Cl- concentration plays a critical role in regulating vesicular trafficking, we hypothesized that the observed defect in endocytosis by the DPUDs could be due to altered Cl- gradient across the cell membrane. Using in vitro assays we demonstrated that the DPUDs transported Cl- into the cell and led to intracellular Cl- accumulation, which possibly affected the endocytic machinery by perturbing intracellular Cl- homeostasis. Finally, we tested the DPUDs in mice challenged with IAV and mouse-adapted SARS-CoV-2 (MA 10). Treatment of the infected mice with the DPUDs led to remarkable body weight recovery, improved survival and significantly reduced lung viral load, highlighting their potential for development as broad-spectrum antivirals.
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COVID-19 , Vírus da Influenza A , Animais , Camundongos , SARS-CoV-2 , Vírus da Influenza A/fisiologia , Endocitose , Internalização do Vírus , Antivirais/farmacologia , Antivirais/químicaRESUMO
Chemoresistance is a primary cause of breast cancer treatment failure, and protein-protein interactions significantly contribute to chemoresistance during different stages of breast cancer progression. In pursuit of novel biomarkers and relevant protein-protein interactions occurring during the emergence of breast cancer chemoresistance, we used a computational predictive biological (CPB) approach. CPB identified associations of adhesion molecules with proteins connected with different breast cancer proteins associated with chemoresistance. This approach identified an association of Integrin ß1 (ITGB1) with chemoresistance and breast cancer stem cell markers. ITGB1 activated the Focal Adhesion Kinase (FAK) pathway promoting invasion, migration, and chemoresistance in breast cancer by upregulating Erk phosphorylation. FAK also activated Wnt/Sox2 signaling, which enhanced self-renewal in breast cancer. Activation of the FAK pathway by ITGB1 represents a novel mechanism linked to breast cancer chemoresistance, which may lead to novel therapies capable of blocking breast cancer progression by intervening in ITGB1-regulated signaling pathways.
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Neoplasias da Mama , Integrina beta1 , Feminino , Humanos , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Integrina beta1/metabolismoRESUMO
OBJECTIVE: To evaluate the DRRiP (Diabetes Related Risk in Pregnancy) score warning system as a tool for predicting neonatal morbidity in gestational diabetes. METHODS: A retrospective observational cohort study. By applying nine parameters from an antenatal trichotomy of glycemic, ultrasound, and clinical characteristics, DRRiP scores were calculated and assigned to each patient using a checklist tool. Logistic regression models were used to evaluate the association between DRRiP score and adverse fetal outcomes, after adjusting for maternal age and body mass index (calculated as weight in kilograms divided by the square of height in meters). RESULTS: In all, 627 women were studied. DRRiP score was an excellent predictor of macrosomia and shoulder dystocia (both areas under the receiver operating characteristics curves [AUROC] = 0.86), and a modest predictor of preterm delivery, hyperbilirubinemia, neonatal intensive care unit admission and a composite of either of the studied events (AUROC range 0.63-0.69). For the composite outcome, the sensitivity of an amber trigger score of 1 was 68.7% (95% confidence interval [CI] 62.27%-74.63%) and specificity was 48.87% (95% CI 43.85%-53.9%). Specificity at a red trigger score of 3 (89.7%) and a graded increase in post-test probability (90.7% risk at a score of 5) were highly encouraging. CONCLUSION: DRRiP score offers reasonable discriminative performance that could be clinically useful for meaningful risk stratification when making delivery plans.
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Diabetes Gestacional , Nascimento Prematuro , Recém-Nascido , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Estudos Retrospectivos , Macrossomia Fetal/diagnóstico , Idade MaternaRESUMO
Over the last two decades, nanoparticulate delivery systems have revolutionized cancer treatment by achieving target-specific delivery, enhanced bioavailability, and improved toxicity profile. The increasing interest in nanotechnology for cancer treatment stems from the unique physicochemical properties of nanoparticles (for instance, small size, surface characteristics, etc.). Indeed, different anticancer drugs can be effectively delivered through nano-delivery systems nowadays. However, the application of such delivery systems in the arena of gene therapy remains in its infancy. Moreover, the treatment of retinoblastoma (RB), an aggressive ocular cancer of childhood, is a major problem in developing countries owing to the late diagnosis of this type of cancer. While adeno-associated virus-based delivery strategies remain the mainstay of the gene delivery method due to their high efficiency, other delivery systems, such as non-viral nanoparticles (NPs) are being developed as alternative therapeutic modalities. Indeed, different nanoparticle formulations such as lipid-based nanoparticles, polymeric nanoparticles, gold nanoparticles have displayed improved gene delivery efficiency in retinal diseases. This review article focuses on the nanoparticle mediated gene therapy approaches in the treatment of RB and highlights the attempts made to develop improved formulations for the treatment of RB. We delineate the current status of NPs as a gene delivery vehicle and cover the future perspective of this exciting field of research. Also, we discuss the achievement, challenges, and opportunities of nanomedicine to treat RB and mention novel engineering approaches that leverage our growing understanding of tumor biology and mechanisms of NPs uptake to develop more effective nanotherapeutics for RB patients.
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Nanopartículas Metálicas , Nanopartículas , Neoplasias da Retina , Retinoblastoma , Humanos , Sistemas de Liberação de Medicamentos , Retinoblastoma/genética , Retinoblastoma/terapia , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas/química , Terapia Genética , Neoplasias da Retina/genética , Neoplasias da Retina/terapiaRESUMO
The COVID-19 pandemic has spawned global health crisis of unprecedented magnitude, claiming millions of lives and pushing healthcare systems in many countries to the brink. Among several factors that contribute to an increased risk of COVID-19 and progression to exacerbated manifestations, host genetic landscape is increasingly being recognized as a critical determinant of susceptibility/resistance to infection and a prognosticator of clinical outcomes in infected individuals. Recently, several case-control association studies investigated the influence of human gene variants on COVID-19 susceptibility and severity to identify the culpable mutations. However, a comprehensive synthesis of the recent advances in COVID-19 host genetics research was lacking, and the inconsistent findings of the association studies required reliable evaluation of the strength of association with greater statistical power. In this study, we embarked on a systematic search of all possible reports of genetic association with COVID-19 till April 07, 2022, and performed meta-analyses of all the genetic polymorphisms that were examined in at least three studies. After identifying a total of 84 studies that investigated the association of 130 polymorphisms in 61 genes, we performed meta-analyses of all the eligible studies. Seven genetic polymorphisms involving 15,550 cases and 444,007 controls were explored for association with COVID-19 susceptibility, of which, ACE1 I/D rs4646994/rs1799752, APOE rs429358, CCR5 rs333, and IFITM3 rs12252 showed increased risk of infection. Meta-analyses of 11 gene variants involving 6702 patients with severe COVID-19 and 8640 infected individuals with non-severe manifestations revealed statistically significant association of ACE2 rs2285666, ACE2 rs2106809, ACE2 rs2074192, AGTR1 rs5186, and TNFA rs1800629 with COVID-19 severity. Overall, our study presents a synthesis of evidence on all the genetic determinants implicated in COVID-19 to date, and provides evidence of correlation between the above polymorphisms with COVID-19 susceptibility and severity.
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COVID-19 , Enzima de Conversão de Angiotensina 2 , COVID-19/genética , Predisposição Genética para Doença , Genética Humana , Humanos , Proteínas de Membrana/genética , Pandemias , Proteínas de Ligação a RNA/genética , SARS-CoV-2/genéticaRESUMO
A rising health concern with saturated fatty acids allowed researchers to look into the science of replacing these fats with unsaturated fatty acids. Oleogelation is a technique to structure edible oil using gelators. The present study looked for the effect of solid emulsifiers; namely, sorbitan monostearate (SP) and stearyl alcohol (SA), on the physicochemical parameters of oleogels. All the oleogels were formulated using 5% sunflower wax (SW) in sunflower oil (SO). The formulated oleogels displayed irregular-shaped wax crystals on their surface. The bright-field and polarized microscopy showed the fiber/needle network of wax crystals. Formulations consisting of 10 mg (0.05% w/w) of both the emulsifiers (SA10 and SP10) in 20 g of oleogels displayed the appearance of a dense wax crystal network. The SP and SA underwent co-crystallization with wax molecules, which enhanced crystal growth and increased the density and size of the wax crystals. The XRD and FTIR studies suggested the presence of a similar ß' polymorph to that of the triacylglycerols' arrangement. The incorporation of SA and SP in wax crystal packing might have resulted in a lower crystallization rate in SA10 and SP10. Evaluation of the thermal properties of oleogels through DSC showed better gel recurrence of high melting enthalpy. These formulations also displayed a sustained release of curcumin. Despite the variations in several properties (e.g., microstructures, crystallite size, thermal properties, and nutrient release), the emulsifiers did not affect the mechanical properties of the oleogel. The meager amounts of both the emulsifiers were able to modulate the nutrient release from the oleogels without affecting their mechanical properties in comparison to the control sample.
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Fusion genes are abnormal genes resulting from chromosomal translocation, insertion, deletion, inversion, etc. ETV6, a rather promiscuous partner forms fusions with several other genes, most commonly, the NTRK3 gene. This fusion leads to the formation of a constitutively activated tyrosine kinase which activates the Ras-Raf-MEK and PI3K/AKT/MAPK pathways, leading the cells through cycles of uncontrolled division and ultimately resulting in cancer. Targeted therapies against this ETV6-NTRK3 fusion protein are much needed. Therefore, to find a targeted approach, a transcription factor RBPJ regulating the ETV6 gene was established and since the ETV6-NTRK3 fusion gene is downstream of the ETV6 promoter/enhancer, this fusion protein is also regulated. The regulation of the ETV6 gene via RBPJ was validated by ChIP analysis in human glioblastoma (GBM) cell lines and patient tissue samples. This study was further followed by the identification of an inhibitor, Furamidine, against transcription factor RBPJ. It was found to be binding with the DNA binding domain of RBPJ with antitumorigenic properties and minimal organ toxicity. Hence, a new target RBPJ, regulating the production of ETV6 and ETV6-NTRK3 fusion protein was found along with a potent RBPJ inhibitor Furamidine.
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Proteínas de Ligação a DNA , Glioblastoma , Proteínas de Ligação a DNA/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-ets/genética , Receptor trkC/genética , Receptor trkC/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética , Fatores de Transcrição/genéticaRESUMO
Red Blood Cells (RBCs)-derived particles are an emerging group of novel drug delivery systems. The natural attributes of RBCs make them potential candidates for use as a drug carrier or nanoparticle camouflaging material as they are innately biocompatible. RBCs have been studied for multiple decades in drug delivery applications but their evolution in the clinical arena are considerably slower. They have been garnering attention for the unique capability of conserving their membrane proteins post fabrication that help them to stay non-immunogenic in the biological environment prolonging their circulation time and improving therapeutic efficiency. In this review, we discuss about the synthesis, significance, and various biomedical applications of the above-mentioned classes of engineered RBCs. This article is focused on the current state of clinical translation and the analysis of the hindrances associated with the transition from lab to clinic applications.
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The Transforming growth factor-ß1 (TGF- ß1) in the tumor microenvironment (TME) is the major cytokine that acts as a mediator of tumor-stroma crosstalk, which in fact has a dual role in either promoting or suppressing tumor development. The cancer-associated fibroblasts (CAFs) are the major cell types in the TME, and the interaction with most of the epithelial cancers is the prime reason for cancer survival. However, the molecular mechanisms, associated with the TGF- ß1 induced tumor promotion through tumor-CAF crosstalk are not well understood. In the Reverse Warburg effect, CAFs feed the adjacent cancer cells by lactate produced during the aerobic glycolysis. We hypothesized that the monocarboxylate transporter, MCT4 which is implicated in lactate efflux from the CAFs, must be overexpressed in the CAFs. Contextually, to explore the role of TGF- ß1 in the hypoxia-induced autophagy in CAFs, we treated CoCl2 and external TGF- ß1 to the human dermal fibroblasts and L929 murine fibroblasts. We demonstrated that hypoxia accelerated the TGF- ß1 signaling and subsequent transformation of normal fibroblasts to CAFs. Moreover, we elucidated that synergistic induction of autophagy by hypoxia and TGF- ß1 upregulate the aerobic glycolysis and MCT4 expression in CAFs. Furthermore, we showed a positive correlation between glucose consumption and MCT4 expression in the CAFs. Autophagy was also found to be involved in the EMT in hypoxic CAFs. Collectively, these findings reveal the unappreciated role of autophagy in TME, which enhances the CAF transformation and that promotes tumor migration and metastasis via the reverse Warburg effect.
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Autofagia , Fibroblastos Associados a Câncer , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Neoplasias , Fator de Crescimento Transformador beta1/metabolismo , Animais , Fibroblastos Associados a Câncer/patologia , Regulação Neoplásica da Expressão Gênica , Glicólise , Humanos , Hipóxia/metabolismo , Ácido Láctico/metabolismo , Camundongos , Neoplasias/patologia , Microambiente Tumoral , Regulação para CimaRESUMO
Nonalcoholic steatohepatitis (NASH) is characterized by accumulation of lipids in the hepatocytes (steatosis) and chronic inflammation. Liver resident macrophages (Kupffer cells) play a pivotal role in inducing inflammation. Cross-talk between hepatocytes and Kupffer cells (KCs) regulate both steatosis and inflammation during the pathogenesis of NASH. Isolated hepatocytes and KC serve as important tools to study mechanistic events during NASH in an in vitro setting. Because mice and humans share identical genes, primary mouse hepatocytes and KC are valuable ex vivo models for NASH studies. However, isolation of mouse liver cells is challenging and requires specific technical procedure and skills. Here, we elaborate a method for effective isolation of both primary hepatocytes and KC from adult liver of the same mouse. This protocol can be used for isolation of liver cells from both wild-type (WT) and genetically-engineered mice. The principle of the method is based on a two-step collagenase perfusion technique in which the liver is washed by perfusion, liver cells are segregated by collagenase treatment, and hepatocytes and KC are then purified and cultured. We optimized this protocol in terms of reproducibility, yield of different population of liver cells, and viability.
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Células de Kupffer , Hepatopatia Gordurosa não Alcoólica , Animais , Hepatócitos , Fígado , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologia , Reprodutibilidade dos TestesRESUMO
The rapid increase in the incidence of obesity contributes to a parallel increase in nonalcoholic steatohepatitis (NASH). Monocyte-derived macrophages, recruited from the bone marrow to the liver, promote NASH-related inflammation and fibrosis. In addition, adipose tissue macrophages (ATMs) release pro-inflammatory cytokines (PICs) which stimulate adipose tissue lipolysis liberating free fatty acids (FFAs) that can accumulate in the liver as triglycerides (TGs), thereby inducing steatosis. As such, bone marrow-derived macrophages (BMDMs) function as an essential tool to study the pathogenesis of NASH. BMDMs are primary bone marrow-derived cells which are differentiated into macrophages in vitro in the presence of growth factors. Macrophage colony-stimulating factor (M-CSF) is required for the proliferation and differentiation of committed myeloid progenitors into cells of the macrophage/monocyte lineage. Here, we describe a protocol for the isolation of mouse bone marrow cells and subsequent macrophage differentiation in which bone marrow cells are cultured in the presence of M-CSF, supplemented either by conditioned medium from L929 cells or in purified form. The efficiency of the differentiation is confirmed by immunofluorescent staining of macrophage surface antigen F4/80. The BMDMs serve as an excellent ex vivo model for a variety of studies, including hepatocyte-macrophage and adipocyte-macrophage cross-talk regulating NASH.
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Hematopoese , Fator Estimulador de Colônias de Macrófagos , Animais , Células da Medula Óssea , Diferenciação Celular/fisiologia , Células Cultivadas , Fator Estimulador de Colônias de Macrófagos/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/metabolismo , Camundongos , MonócitosRESUMO
BACKGROUND: Aloe vera extract and its bioactive compounds possess anti-proliferative properties against cancer cells. However, no detailed molecular mechanism of action studies has been reported. We have now employed a computational approach to scrutinize the molecular mechanism of lead bioactive compounds from Aloe vera that potentially inhibit DNA synthesis. METHODS: Initially, the anti-proliferative activity of Aloe vera extract was examined in human breast cancer cells (in vitro/in vivo). Later on, computational screening of bioactive compounds from Aloe vera targeting DNA was performed by molecular docking and molecular dynamics simulation. RESULTS: In-vitro and in-vivo studies confirm that Aloe vera extract effectively suppresses the growth of breast cancer cells without significant cytotoxicity towards non-cancerous normal immortal cells. Computational screening predicts that growth suppression may be due to the presence of DNA intercalating bioactive compounds (riboflavin, daidzin, aloin, etc.) contained in Aloe vera. MM/PBSA calculation showed that riboflavin has a higher binding affinity at the DNA binding sites compared to standard drug daunorubicin. CONCLUSIONS: These observations support the hypothesis that riboflavin may be exploited as an anti-proliferative DNA intercalating agent to prevent cancer and is worthy of testing for the management of cancer by performing more extensive pre-clinical and if validated clinical trials.
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Aloe , Neoplasias , Aloe/química , DNA , Humanos , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologiaRESUMO
Obesity is an enormous global health problem, and obesity-induced nonalcoholic steatohepatitis (NASH) is contributing to a rising incidence and mortality for hepatocellular carcinoma (HCC). Increase in de novo lipogenesis and decrease in fatty acid ß-oxidation (FAO) underlie hepatic lipid accumulation in NASH. Astrocyte-elevated gene-1/metadherin (AEG-1) overexpression contributes to both NASH and HCC. AEG-1 harbors an LXXLL motif through which it blocks activation of peroxisome proliferator activated receptor α (PPARα), a key regulator of FAO. To better understand the role of LXXLL motif in mediating AEG-1 function, using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology, we generated a mouse model (AEG-1-L24K/L25H) in which the LXXLL motif in AEG-1 was mutated to LXXKH. We observed increased activation of PPARα in AEG-1-L24K/L25H livers providing partial protection from high-fat diet-induced steatosis. Interestingly, even with equal gene dosage levels, compared with AEG-1-wild-type livers, AEG-1-L24K/L25H livers exhibited increase in levels of lipogenic enzymes, mitogenic activity and inflammation, which are attributes observed when AEG-1 is overexpressed. These findings indicate that while LXXLL motif favors steatotic activity of AEG-1, it keeps in check inflammatory and oncogenic functions, thus maintaining a homeostasis in AEG-1 function. AEG-1 is being increasingly appreciated as a viable target for ameliorating NASH and NASH-HCC, and as such, in-depth understanding of the functions and molecular attributes of this molecule is essential. Conclusion: The present study unravels the unique role of the LXXLL motif in mediating the balance between the metabolic and oncogenic functions of AEG-1.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas de Membrana , Hepatopatia Gordurosa não Alcoólica , Proteínas de Ligação a RNA , Animais , Astrócitos/metabolismo , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Camundongos , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade/genética , PPAR alfa/genética , Proteínas de Ligação a RNA/genética , Fatores de TranscriçãoRESUMO
Isolated fallopian tube torsion is an extremely rare occurrence in a young female. The lady concerned presented with acute abdominal pain and the ovaries were normal on the scan with dilated fallopian tubes. On laparoscopy, it was revealed that she was suffering from fallopian tube torsion and laparoscopic salpingectomy was performed. The patient recovered well postoperatively.
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The use of an appropriate oleogelator in the structuring of vegetable oil is a crucial point of consideration. Sunflower wax (SFW) is used as an oleogelator and displays an excellent potential to bind vegetable oils. The current study aimed to look for the effects of hydrophobic (SPAN-80) and hydrophilic (TWEEN-80) emulsifiers on the oleogels prepared using SFW and sunflower oil (SO). The biodegradability and all formulations showed globular crystals on their surface that varied in size and number. Wax ester, being the most abundant component of SFW, was found to produce fibrous and needle-like entanglements capable of binding more than 99% of SO. The formulations containing 3 mg of liquid emulsifiers in 20 g of oleogels showed better mechanical properties such as spreadability and lower firmness than the other tested concentrations. Although the FTIR spectra of all the formulations were similar, which indicated not much variation in the molecular interactions, XRD diffractograms confirmed the presence of ß' form of fat crystals. Further, the mentioned formulations also showed larger average crystallite sizes, which was supported by slow gelation kinetics. A characteristic melting point (Tm~60 °C) of triglyceride was visualized through DSC thermograms. However, a higher melting point in the case of few formulations suggests the possibility of even a stable ß polymorph. The formed oleogels indicated the significant contribution of diffusion for curcumin release. Altogether, the use of SFW and SO oleogels with modified properties using biodegradable emulsifiers can be beneficial in replacing saturated fats and fat-derived products.
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An array of human cancers, including hepatocellular carcinoma (HCC), overexpress the oncogene Astrocyte elevated gene-1 (AEG-1). It is now firmly established that AEG-1 is a key driver of carcinogenesis, and enhanced expression of AEG-1 is a marker of poor prognosis in cancer patients. In-depth studies have revealed that AEG-1 positively regulates different hallmarks of HCC progression including growth and proliferation, angiogenesis, invasion, migration, metastasis and resistance to therapeutic intervention. By interacting with a plethora of proteins as well as mRNAs, AEG-1 regulates gene expression at transcriptional, post-transcriptional, and translational levels, and modulates numerous pro-tumorigenic and tumor-suppressive signal transduction pathways. Even though extensive research over the last two decades using various in vitro and in vivo models has established the pivotal role of AEG-1 in HCC, effective targeting of AEG-1 as a therapeutic intervention for HCC is yet to be achieved in the clinic. Targeted delivery of AEG-1 small interfering ribonucleic acid (siRNA) has demonstrated desired therapeutic effects in mouse models of HCC. Peptidomimetic inhibitors based on protein-protein interaction studies has also been developed recently. Continuous unraveling of novel mechanisms in the regulation of HCC by AEG-1 will generate valuable knowledge facilitating development of specific AEG-1 inhibitory strategies. The present review describes the current status of AEG-1 in HCC gleaned from patient-focused and bench-top studies as well as transgenic and knockout mouse models. We also address the challenges that need to be overcome and discuss future perspectives on this exciting molecule to transform it from bench to bedside.