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1.
Exp Cell Res ; 435(1): 113907, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38184222

RESUMO

Neosetophomone B (NSP-B) is a unique meroterpenoid fungal secondary metabolite that has previously demonstrated promising anti-cancer properties against various cancer cell lines in vitro. However, its in vivo anti-cancer potential remaines unexplored. To fill this gap in our knowledge, we tested NSP-B's in vivo anti-cancer activity using a zebrafish model, an organism that has gained significant traction in biomedical research due to its genetic similarities with humans and its transparent nature, allowing real-time tumor growth observation. For our experiments, we employed the K562-injected zebrafish xenograft model. Upon treating these zebrafish with NSP-B, we observed a marked reduction in the size and number of tumor xenografts. Delving deeper, our analyses indicated that NSP-B curtailed tumor growth and proliferation of leukemic grafted xenograft within the zebrafish. These results show that NSP-B possesses potent in vivo anti-cancer properties, making it a potential novel therapeutic agent for addressing hematological malignancies.


Assuntos
Neoplasias , Peixe-Zebra , Animais , Humanos , Peixe-Zebra/metabolismo , Xenoenxertos , Modelos Animais de Doenças , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Nitric Oxide ; 144: 47-57, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38307377

RESUMO

Heart failure (HF) is a multifactorial, heterogeneous systemic disease that is considered one of the leading causes of death and morbidity worldwide. It is well-known that endothelial dysfunction (ED) plays an important role in cardiac disease etiology. A reduction in the bioavailability of nitric oxide (NO) in the bloodstream leads to vasoconstriction and ED. Many studies indicated diminishment of peripheral arteries vasodilation that is mediated by the endothelium in the of patients with chronic HF. With the advancement of nanomedicine, nanotechnology can provide adequate solutions for delivering exogenous NO with the aid of nanoparticles (NPs) to treat ED. The properties of superparamagnetic iron oxide nanoparticles (SPIONs) enable both passive and active delivery of drugs. This prompted us to investigate the efficacy of our newly-developed hydrogel nanoparticles (NO-RPs) for the delivery and sustained release of NO gas to alleviate cardiac failure and inflammation in the heart failure zebrafish model. The hydrogel NO-RPs incorporate SPIONS and NO precursor. The sustainend release of NO in the NO-RPs (4200 s), overcomes the problem of the short half life of NO in vivo which is expected to ameliorate the reduced NO bioavailabilty, and its consequences in endothelial and cardiac dysfunction. Zebrafish embryos were used as the animal model in this study to determine the effect of SPIONs-loaded NO-RPs on the cardiovascular system. Cardiac failure was induced in 24hpf embryos by exposure to aristolochic acid (AA)(0.25, 0.5 µM) for 8 h, followed by the SPIONs-loaded NO-RPs (0.25, 0.5 mg/ml) for 48 h, experimental groups included: control group which is healthy non treated zebrafish embryos, AA injured zebrafish embryos (HF) model,and NO-RP treated HF zebrafish embryos. Survival rate was assessed at 72hpf. Cardiac function was also evaluated by analyzing cardiac parameters including heartbeat, major blood vessels primordial cardinal vein and dorsal aorta (PCV &DA) diameter, blood flow velocity in PCV & DA vessels, cardiac output, and PCV & DA shear stresses. All cardiac parameters were analyzed with the aid of MicroZebraLab blood flow analysis software from Viewpoint. In addition, we studied the molecular effects of the developed NO-RPs on the mRNA expression of selected pro-inflammatory markers: IL-6, and Cox-2. Our findings demonstrated that the NO-RPs improved the survival rate in the heart failure zebrafish model and reversed heart failure by enhancing blood flow perfusion in Zebrafish embryos, significantly. In addition, RT-PCR results showed that the NO-RPs significantly reduced the expression of pro-inflammatory markers (lL-6&COX-2) in the heart failure zebrafish model. Our study confirmed that the developed SPIONs-loaded NO-RPs are effective tool to alleviate cardiac failure and inflammation in the HF zebrafish model.


Assuntos
Estruturas Embrionárias , Insuficiência Cardíaca , Nanopartículas , Sistema Porta/embriologia , Humanos , Animais , Peixe-Zebra , Óxido Nítrico/uso terapêutico , Ciclo-Oxigenase 2 , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Inflamação/induzido quimicamente , Hidrogéis/efeitos adversos
3.
Dev Dyn ; 252(10): 1247-1268, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37002896

RESUMO

High resolution assessment of cardiac functional parameters is crucial in translational animal research. The chick embryo is a historically well-used in vivo model for cardiovascular research due to its many practical advantages, and the conserved form and function of the chick and human cardiogenesis programs. This review aims to provide an overview of several different technical approaches for chick embryo cardiac assessment. Doppler echocardiography, optical coherence tomography, micromagnetic resonance imaging, microparticle image velocimetry, real-time pressure monitoring, and associated issues with the techniques will be discussed. Alongside this discussion, we also highlight recent advances in cardiac function measurements in chick embryos.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Coração , Animais , Embrião de Galinha , Humanos , Velocidade do Fluxo Sanguíneo/fisiologia , Coração/fisiologia , Tomografia de Coerência Óptica/métodos , Hemodinâmica
4.
Pflugers Arch ; 474(1): 63-81, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34967935

RESUMO

Experimental and clinical evidence suggests that diabetic subjects are predisposed to a distinct cardiovascular dysfunction, known as diabetic cardiomyopathy (DCM), which could be an autonomous disease independent of concomitant micro and macrovascular disorders. DCM is one of the prominent causes of global morbidity and mortality and is on a rising trend with the increase in the prevalence of diabetes mellitus (DM). DCM is characterized by an early left ventricle diastolic dysfunction associated with the slow progression of cardiomyocyte hypertrophy leading to heart failure, which still has no effective therapy. Although the well-known "Renin Angiotensin Aldosterone System (RAAS)" inhibition is considered a gold-standard treatment in heart failure, its role in DCM is still unclear. At the cellular level of DCM, RAAS induces various secondary mechanisms, adding complications to poor prognosis and treatment of DCM. This review highlights the importance of RAAS signaling and its major secondary mechanisms involving inflammation, oxidative stress, mitochondrial dysfunction, and autophagy, their role in establishing DCM. In addition, studies lacking in the specific area of DCM are also highlighted. Therefore, understanding the complex role of RAAS in DCM may lead to the identification of better prognosis and therapeutic strategies in treating DCM.


Assuntos
Cardiomiopatias Diabéticas/etiologia , Sistema Renina-Angiotensina , Angiotensina II/metabolismo , Animais , Autofagia , Cardiomiopatias Diabéticas/metabolismo , Humanos , Inflamação/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Estresse Oxidativo , Peptidil Dipeptidase A/metabolismo , Receptores de Angiotensina/metabolismo
5.
Blood Press ; 31(1): 80-90, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35548940

RESUMO

PURPOSE: This study examines the effect of antihypertensive drugs on ACE2 and Angiotensin II levels in hypertensive COVID-19 patients. INTRODUCTION: Hypertension is a common comorbidity among severe COVID-19 patients. ACE2 expression can be modulated by antihypertensive drugs such as ACEis and ARBs, which may affect COVID-19's prognosis. BB and CCB reduce mortality, according to some evidence. Their effect on circulating levels of ACE2 and angiotensin II, as well as the severity of COVID-19, is less well studied. MATERIALS AND METHODS: The clinical data were collected from 200 patients in four different antihypertensive medication classes (ACEi, ARB, BB, and CCB). Angiotensin II and ACE2 levels were determined using standard ELISA kits. ACE2, angiotensin II, and other clinical indices were evaluated by linear regression models. RESULTS: Patients on ACEi (n = 57), ARB (n = 68), BB (n = 15), or CCB (n = 30) in this study had mild (n = 76), moderate (n = 76), or severe (n = 52) COVID-19. ACE2 levels were higher in COVID-19 patients with severe disease (p = 0.04) than mild (p = 0.07) and moderate (p = 0.007). The length of hospital stay is correlated with ACE2 levels (r = 0.3, p = 0.003). Angiotensin II levels decreased with severity (p = 0.04). Higher ACE2 levels are associated with higher CRP and D-dimer levels. Elevated Angiotensin II was associated with low levels of CRP, D-dimer, and troponin. ACE2 levels increase with disease severity in patients taking an ARB (p = 0.01), patients taking ACEi, the degree of disease severity was associated with a decrease in angiotensin II. BB patients had the lowest disease severity. CONCLUSION: We found different levels of soluble ACE2, and angiotensin II are observed among COVID-19 patients taking different antihypertensive medications and exhibiting varying levels of disease severity. COVID-19 severity increases with elevated ACE2 levels and lower angiotensin II levels indicating that BB treatment reduces severity regardless of levels of ACE2 and angiotensin II.


Assuntos
Tratamento Farmacológico da COVID-19 , Hipertensão , Angiotensina II , Antagonistas de Receptores de Angiotensina/uso terapêutico , Enzima de Conversão de Angiotensina 2 , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico
6.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201415

RESUMO

The SARS-CoV-2 virus utilizes angiotensin converting enzyme (ACE-2) for cell entry and infection. This enzyme has important functions in the renin-angiotensin aldosterone system to preserve cardiovascular function. In addition to the heart, it is expressed in many tissues including the lung, intestines, brain, and kidney, however, its functions in these organs are mostly unknown. ACE-2 has membrane-bound and soluble forms. Its expression levels are altered in disease states and by a variety of medications. Currently, it is not clear how altered ACE-2 levels influence ACE-2 virulence and relevant complications. In addition, membrane-bound and soluble forms are thought to have different effects. Most work on this topic in the literature is on the SARS-CoV virus that has a high genetic resemblance to SARS-Co-V-2 and also uses ACE-2 enzyme to enter the cell, but with much lower affinity. More recent studies on SARS-CoV-2 are mainly clinical studies aiming at relating the effect of medications that are thought to influence ACE-2 levels, with COVID-19 outcomes for patients under these medications. This review paper aims to summarize what is known about the relationship between ACE-2 levels and SARS-CoV/SARS-CoV-2 virulence under altered ACE-2 expression states.


Assuntos
Enzima de Conversão de Angiotensina 2/fisiologia , COVID-19/fisiopatologia , COVID-19/virologia , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/química , Inibidores da Enzima Conversora de Angiotensina , Interações entre Hospedeiro e Microrganismos , Humanos , Pulmão/metabolismo , Virulência
7.
J Cell Physiol ; 235(11): 7870-7888, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31943169

RESUMO

Myosin-binding protein C 3 (MYBPC3) variants are the most common cause of hypertrophic cardiomyopathy (HCM). HCM is a complex cardiac disorder due to its significant genetic and clinical heterogeneity. MYBPC3 variants genotype-phenotype associations remain poorly understood. We investigated the impact of two novel human MYBPC3 splice-site variants: V1: c.654+2_654+4dupTGG targeting exon 5 using morpholino MOe5i5; and V2: c.772+1G>A targeting exon 6 using MOe6i6; located within C1 domain of cMyBP-C protein, known to be critical in regulating sarcomere structure and contractility. Zebrafish MOe5i5 and MOe6i6 morphants recapitulated typical characteristics of human HCM with cardiac phenotypes of varying severity, including reduced cardiomyocyte count, thickened ventricular myocardial wall, a drastic reduction in heart rate, stroke volume, and cardiac output. Analysis of all cardiac morphological and functional parameters demonstrated that V2 cardiac phenotype was more severe than V1. Coinjection with synthetic human MYBPC3 messenger RNA (mRNA) partially rescued disparate cardiac phenotypes in each zebrafish morphant. While human MYBPC3 mRNA partially restored the decreased heart rate in V1 morphants and displayed increased percentages of ejection fraction, fractional shortening, and area change, it failed to revert the V1 ventricular myocardial thickness. These results suggest a possible V1 impact on cardiac contractility. In contrast, attempts to rescue V2 morphants only restored the ventricular myocardial wall hypertrophy phenotype but had no significant effect on impaired heart rate, suggesting a potential V2 impact on the cardiac structure. Our study provides evidence of an association between MYBPC3 exon-specific cardiac phenotypes in the zebrafish model providing important insights into how these genetic variants contribute to HCM disease.


Assuntos
Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/patologia , Proteínas de Transporte/genética , Animais , Modelos Animais de Doenças , Éxons/genética , Humanos , Fenótipo , Isoformas de Proteínas/genética , Peixe-Zebra
8.
Arterioscler Thromb Vasc Biol ; 38(12): 2806-2818, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30571172

RESUMO

Objective- Endothelial cells (ECs) sense and respond to flow-induced mechanical stress, in part, via microtubule-based projections called primary cilia. However, many critical steps during vascular morphogenesis occur independent of flow. The involvement of cilia in regulating these stages of cranial vascular morphogenesis is poorly understood because cilia have not been visualized in primary head vessels. The objective of this study was to investigate involvement of cilia in regulating the early stages of cranial vascular morphogenesis. Approach and Results- Using high-resolution imaging of the Tg(kdrl:mCherry-CAAX) y171 ;(bactin::Arl13b:GFP) zebrafish line, we showed that cilia are enriched in the earliest formed cranial vessels that assemble via vasculogenesis and in angiogenic hindbrain capillaries. Cilia were more prevalent around the boundaries of putative intravascular spaces in primary and angiogenic vessels. Loss of cardiac contractility and blood flow, because of knockdown of cardiac troponin T type 2a ( tnnt2a) expression, did not affect the distribution of cilia in primary head vasculature. In later stages of development, cilia were detected in retinal vasculature, areas of high curvature, vessel bifurcation points, and during vessel anastomosis. Loss of genes crucial for cilia biogenesis ( ift172 and ift81) induced intracerebral hemorrhages in an EC-autonomous manner. Exposure to high shear stress induced premature cilia disassembly in brain ECs and was associated with intracerebral hemorrhages. Conclusions- Our study suggests a functional role for cilia in brain ECs, which is associated with the emergence and remodeling of the primary cranial vasculature. This cilia function is flow-independent, and cilia in ECs are required for cerebral-vascular stability.


Assuntos
Artérias Cerebrais/embriologia , Veias Cerebrais/embriologia , Cílios , Células Endoteliais , Endotélio Vascular/embriologia , Neovascularização Fisiológica , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Artérias Cerebrais/metabolismo , Veias Cerebrais/metabolismo , Cílios/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Malformações Arteriovenosas Intracranianas/embriologia , Malformações Arteriovenosas Intracranianas/genética , Malformações Arteriovenosas Intracranianas/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Mecanotransdução Celular , Morfogênese , Troponina T/genética , Troponina T/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteína Vermelha Fluorescente
9.
Int J Mol Sci ; 20(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974769

RESUMO

Several congenital and acquired conditions may result in severe narrowing of the urethra in men, which represent an ongoing surgical challenge and a significant burden on both health and quality of life. In the field of urethral reconstruction, tissue engineering has emerged as a promising alternative to overcome some of the limitations associated with autologous tissue grafts. In this direction, preclinical as well as clinical studies, have shown that degradable scaffolds are able to restore the normal urethral architecture, supporting neo-vascularization and stratification of the tissue. While a wide variety of degradable biomaterials are under scrutiny, such as decellularized matrices, natural, and synthetic polymers, the search for scaffold materials that could fulfill the clinical performance requirements continues. In this article, we discuss the design requirements of the scaffold that appear to be crucial to better resemble the structural, physical, and biological properties of the native urethra and are expected to support an adequate recovery of the urethral function. In this context, we review the biological performance of the degradable polymers currently applied for urethral reconstruction and outline the perspectives on novel functional polymers, which could find application in the design of customized urethral constructs.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis/uso terapêutico , Procedimentos de Cirurgia Plástica , Engenharia Tecidual , Alicerces Teciduais , Uretra , Animais , Humanos , Masculino , Qualidade de Vida , Uretra/metabolismo , Uretra/patologia , Uretra/cirurgia
10.
Nutr Cancer ; 70(2): 297-305, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29300111

RESUMO

Oral cancer is a common malignancy in both men and women worldwide; this cancer is characterized by a marked propensity for invasion and spreading to local lymph nodes. On the other hand, Elaeagnus angustifolia (EA) is a medicinal plant that has been used for centuries for treating many human diseases in the Middle East. However, the effect of EA plant extract on human cancers especially oral has not been investigated yet. Thus, first we examined the outcome of EA flower extract on angiogenesis, using the chorioallantoic membrane (CAM) of the chicken embryo; we found that EA extract reduces blood vessel development of the CAM. Then, we investigated the effect of EA flower extract on selected parameters in FaDu and SCC25 oral cancer cell lines. Our results show that EA extract inhibits cell proliferation and colony formation, in addition to the initiation of S cell cycle arrest and reduction of G1/G2 phase. In parallel, EA extract provokes differentiation to an epithelial phenotype "mesenchymal-to-epithelial transition: MET" which is the opposite of "epithelial-to-mesenchymal transition, EMT": an important event in cell invasion and metastasis. Thus, EA plant extract causes a dramatic decrease in cell invasion and motility abilities of FaDu and SCC25 cancer cells in comparison with their controls. These changes are accompanied by an upregulation of E-cadherin expression. The molecular pathway analysis of the EA flower extract reveals that it can inhibit the phosphorylation of Erk1/Erk2, which could be behind the inhibition of angiogenesis, the initiation of MET event, and the overexpression of E-cadherin. Our findings indicate that EA plant extract can reduce human oral cancer progression by the inhibition of angiogenesis and cell invasion via Erk1/Erk2 signaling pathways.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Elaeagnaceae/química , Neoplasias Bucais/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/patologia , Humanos , Proteína Quinase 1 Ativada por Mitógeno , Proteína Quinase 3 Ativada por Mitógeno , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Fosforilação/efeitos dos fármacos
11.
Nicotine Tob Res ; 20(4): 502-507, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28605482

RESUMO

Background: Water-pipe smoking (WPS) is the most widespread tobacco use in the Middle-East, and is rapidly spreading globally. Smoke from WP contains most of the compounds present in cigarette smoke, although in different proportions. WPS is associated with the risk of several human diseases; however, its impact on the early stage of normal development has not been investigated yet. Thus, in this investigation, we assess the effect of WPS on the embryo at the early stage of development. Methods: Chicken embryos at 3 days of incubations were used in this study. Meanwhile, we explored the outcome of WPS on angiogenesis using the chorioallantoic membrane (CAM) of the chicken embryos. Finally, quantitative real-time polymerase chain reaction was used to study the regulation of some key control genes of cell proliferation, apoptosis, and migration. Results: Our data reveal that WPS inhibits angiogenesis of the CAM and in embryos in comparison with their matched controls; in addition, WPS-exposed embryos show slight reduction in their sizes. We also noted that around 80% of WPS-exposed embryos die before 10 days of incubation. More significantly, WPS induces upregulations of BCL-2, Caspase-8, ATF-3, INHIB-A, and Cadherin 6 genes, which are important key regulators of cell apoptosis, proliferation, and migration. Conclusion: Our data reveal, for the first time, that WPS has very toxic effects during the early stage of embryogenesis. Thus, we believe that further studies are required to elucidate the pathogenic effect of WPS on human health especially on the embryo at the early stage of its development. Implications: This investigation addresses an important gap on the outcome of WPS during the early stage of embryogenesis. Data of this study point out that WPS can have a very toxic effect on the embryo at this stage. Additionally, results from this report display for the first time that WPS can damage normal angiogenesis of the embryo thus provoking a significant number of embryonic death. Moreover, this study reveals that this effect can occur via the deregulation of several genes related to cell apoptosis, proliferation, and migration.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/patologia , Fumar Cachimbo de Água/efeitos adversos , Animais , Embrião de Galinha , Desenvolvimento Embrionário/fisiologia , Feminino , Regulação da Expressão Gênica , Oriente Médio , Neovascularização Patológica/induzido quimicamente , Neovascularização Patológica/patologia , Gravidez , Fumaça/efeitos adversos
12.
Dev Dyn ; 246(11): 868-880, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28249360

RESUMO

The Zebrafish has emerged to become a powerful vertebrate animal model for cardiovascular research in recent years. Its advantages include easy genetic manipulation, transparency, small size, low cost, and the ability to survive without active circulation at early stages of development. Sequencing the whole genome and identifying ortholog genes with human genome made it possible to induce clinically relevant cardiovascular defects via genetic approaches. Heart function and disturbed hemodynamics need to be assessed in a reliable manner for these disease models in order to reveal the mechanobiology of induced defects. This effort requires precise determination of blood flow patterns as well as hemodynamic stress (i.e., wall shear stress and pressure) levels within the developing heart. While traditional approach involves time-lapse brightfield microscopy to track cell and tissue movements, in more recent studies fast light-sheet fluorescent microscopes are utilized for that purpose. Integration of more complicated techniques like particle image velocimetry and computational fluid dynamics modeling for hemodynamic analysis holds a great promise to the advancement of the Zebrafish studies. Here, we discuss the latest developments in heart function and hemodynamic analysis for Zebrafish embryos and conclude with our future perspective on dynamic analysis of the Zebrafish cardiovascular system. Developmental Dynamics 246:868-880, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Coração/embriologia , Hemodinâmica/fisiologia , Peixe-Zebra/embriologia , Animais , Velocidade do Fluxo Sanguíneo , Embrião não Mamífero , Coração/fisiologia , Estresse Mecânico , Peixe-Zebra/fisiologia
13.
BMC Biomed Eng ; 6(1): 3, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654382

RESUMO

Compared to classical techniques of morphological analysis, micro-CT (µ-CT) has become an effective approach allowing rapid screening of morphological changes. In the present work, we aimed to provide an optimized micro-CT dense agent perfusion protocol and µ-CT guidelines for different stages of chick embryo cardiogenesis. Our study was conducted over a period of 10 embryonic days (Hamburger-Hamilton HH36) in chick embryo hearts. During the perfusion of the micro-CT dense agent at different developmental stages (HH19, HH24, HH27, HH29, HH31, HH34, HH35, and HH36), we demonstrated that durations and volumes of the injected contrast agent gradually increased with the heart developmental stages contrary to the flow rate that was unchanged during the whole experiment. Analysis of the CT imaging confirmed the efficiency of the optimized parameters of the heart perfusion.

14.
Biomed Mater ; 19(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38194708

RESUMO

Regeneration of damaged urethral tissue remains a major challenge in the field of lower urinary tract reconstruction. To address this issue, various synthetic and natural biodegradable biomaterials are currently being explored for the fabrication of scaffolds that promote urethral regeneration and healing. In this study, we present an approach to fabricate a trilayer hybrid scaffold comprising a central layer of poly(lactic acid) (PLA) between two layers of chitosan. The chitosan/PLA/chitosan (CPC) scaffolds were fabricated by a sequential electrospinning process and their properties were evaluated for their suitability for urethral tissue engineering. The physical and biological properties of the CPC scaffolds were evaluated in comparison to electrospun PLA scaffolds and acellular dermis (Alloderm) as controls for a synthetic and a natural scaffold, respectively. Compared to the controls, the CPC scaffolds exhibited higher elastic modulus and ultimate tensile strength, while maintaining extensibility and suture retention strength appropriate for clinical use. The CPC scaffolds displayed significant hydrophilicity, which was associated with a higher water absorption capacity of the chitosan nanofibres. The degradation products of the CPC scaffolds did not exhibit cytotoxicity and promoted wound closure by fibroblastsin vitro. In addition, CPC scaffolds showed increased growth of smooth muscle cells, an essential component for functional regeneration of urethral tissue. Furthermore, in a chicken embryo-based assay, CPC scaffolds demonstrated significantly higher angiogenic potential, indicating their ability to promote vascularisation, a crucial aspect for successful urethral reconstruction. Overall, these results suggest that CPC hybrid scaffolds containing both natural and synthetic components offer significant advantages over conventional acellular or synthetic materials alone. CPC scaffolds show promise as potential candidates for further research into the reconstruction of the urethrain vivo.


Assuntos
Quitosana , Alicerces Teciduais , Embrião de Galinha , Animais , Materiais Biocompatíveis , Engenharia Tecidual/métodos , Poliésteres
15.
Biomedicines ; 12(6)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38927390

RESUMO

The sperm-specific phospholipase C zeta (PLCζ) protein is widely considered as the predominant physiological stimulus for initiating the Ca2+ release responsible for oocyte activation during mammalian fertilization. The increasing number of genetic and clinical reports that directly link PLCζ defects and/or deficiencies with oocyte activation failure (OAF) necessitates the use of a powerful therapeutic intervention to overcome such cases of male factor infertility. Currently, in vitro fertilization (IVF) clinics treat OAF cases after intracytoplasmic sperm injection (ICSI) with Ca2+ ionophores. Despite their successful use, such chemical agents are unable to trigger the physiological pattern of Ca2+ oscillations. Moreover, the safety of these ionophores is not yet fully established. We have previously demonstrated that recombinant PLCζ protein can be successfully used to rescue failed oocyte activation, resulting in efficient blastocyst formation. Herein, we produced a maltose binding protein (MBP)-tagged recombinant human PLCζ protein capable of inducing Ca2+ oscillations in mouse oocytes similar to those observed at fertilization. Circular dichroism (CD) experiments revealed a stable, well-folded protein with a high helical content. Moreover, the recombinant protein could retain its enzymatic properties for at least up to 90 days after storage at -80 °C. Finally, a chick embryo model was employed and revealed that exposure of fertilized chicken eggs to MBP-PLCζ did not alter the embryonic viability when compared to the control, giving a first indication of its safety. Our data support the potential use of the MBP-PLCζ recombinant protein as an effective therapeutic tool but further studies are required prior to its use in a clinical setting.

16.
J Cardiovasc Transl Res ; 16(5): 975-986, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37052784

RESUMO

Sodium-glucose co-transporter 2 (SGLT2) inhibitors represent one type of new-generation type 2 diabetes (T2DM) drug treatment. The mechanism of action of an SGLT2 inhibitor (SGLT2i) in treating T2DM depends on lowering blood glucose levels effectively via increasing the glomerular excretion of glucose. A good number of randomized clinical trials revealed that SGLT2is significantly prevented heart failure (HF) and cardiovascular death in T2DM patients. Despite ongoing clinical trials in HF patients without T2DM, there have been a limited number of translational studies on the cardioprotective properties of SGLT2is. As the cellular mechanism behind the cardiac benefits of SGLT2is is still to be elucidated, animal models are used to better understand the pathways behind the cardioprotective mechanism of SGLT2i. In this review, we summarize the animal models constructed to study the cardioprotective mechanisms of SGLT2is to help deliver a more comprehensive understanding of the in vivo work that has been done in this field and to help select the most optimal animal model to use when studying the different cardioprotective effects of SGLT2is.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Glucosídeos/farmacologia , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/prevenção & controle , Glucose
17.
Int J Cardiol ; 389: 131238, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37536420

RESUMO

Hemodynamic shear stress is one of the major factors that are involved in the pathogenesis of many cardiovascular diseases including atherosclerosis and abdominal aortic aneurysm (AAA), through its modulatory effect on the endothelial cell's redox homeostasis and mechanosensitive gene expression. Among important mechanisms, oxidative stress, endoplasmic reticulum stress activation, and the subsequent endothelial dysfunction are attributed to disturbed blood flow and low shear stress in the vascular curvature and bifurcations which are considered atheroprone regions and aneurysm occurrence spots. Many pathways were shown to be involved in AAA progression. Of particular interest from recent findings is, the (Nrf2)/Keap-1 pathway, where Nrf2 is a transcription factor that has antioxidant properties and is strongly associated with several CVDs, yet, the exact mechanism by which Nrf2 alleviates CVDs still to be elucidated. Nrf2 expression is closely affected by shear stress and was shown to participate in AAA. In the current review paper, we discussed the link between disturbed hemodynamics and its effect on Nrf2 as a mechanosensitive gene and its role in the development of endothelial dysfunction which is linked to the progression of AAA.


Assuntos
Aneurisma da Aorta Abdominal , Aterosclerose , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Aterosclerose/genética , Hemodinâmica , Aneurisma da Aorta Abdominal/metabolismo , Estresse Mecânico
18.
Artigo em Inglês | MEDLINE | ID: mdl-37725271

RESUMO

Targeted therapy, such as tyrosine kinase inhibitors (TKIs), has been approved to manage various cancer types. However, TKI-induced cardiotoxicity is a limiting factor for their use. This issue has raised the need for investigating potential cardioprotective techniques to be combined with TKIs. Ribosomal S6-kinases (RSKs) are a downstream effector of the mitogen-activated-protein-kinase (MAPK) pathway; specific RSK isoforms, such as RSK1 and RSK2, have been expressed in cancer cells, in which they increase tumour proliferation. Selective targeting of those isoforms would result in tumour suppression. Moreover, activation of RSKs expressed in the heart has resulted in cardiac hypertrophy and arrhythmia; thus, inhibiting RSKs would result in cardio-protection. This review article presents an overview of the usefulness of RSK inhibitors that can be novel agents to be assessed in future research for their effect in reducing cancer proliferation, as well as protecting the heart from cardiotoxicity induced by TKIs.

19.
J Clin Med ; 12(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37510889

RESUMO

Aortic valve defects are among the most prevalent clinical conditions. A severely damaged or non-functioning aortic valve is commonly replaced with a bioprosthetic heart valve (BHV) via the transcatheter aortic valve replacement (TAVR) procedure. Accurate pre-operative planning is crucial for a successful TAVR outcome. Assessment of computational fluid dynamics (CFD), finite element analysis (FEA), and fluid-solid interaction (FSI) analysis offer a solution that has been increasingly utilized to evaluate BHV mechanics and dynamics. However, the high computational costs and the complex operation of computational modeling hinder its application. Recent advancements in the deep learning (DL) domain can offer a real-time surrogate that can render hemodynamic parameters in a few seconds, thus guiding clinicians to select the optimal treatment option. Herein, we provide a comprehensive review of classical computational modeling approaches, medical imaging, and DL approaches for planning and outcome assessment of TAVR. Particularly, we focus on DL approaches in previous studies, highlighting the utilized datasets, deployed DL models, and achieved results. We emphasize the critical challenges and recommend several future directions for innovative researchers to tackle. Finally, an end-to-end smart DL framework is outlined for real-time assessment and recommendation of the best BHV design for TAVR. Ultimately, deploying such a framework in future studies will support clinicians in minimizing risks during TAVR therapy planning and will help in improving patient care.

20.
Dev Dyn ; 240(1): 23-35, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21181939

RESUMO

In this study, we develop an innovative approach to rigorously quantify the evolving hemodynamic environment of the atrioventricular (AV) canal of avian embryos. Ultrasound generated velocity profiles were imported into Micro-Computed Tomography generated anatomically precise cardiac geometries between Hamburger-Hamilton (HH) stages 17 and 30. Computational fluid dynamic simulations were then conducted and iterated until results mimicked in vivo observations. Blood flow in tubular hearts (HH17) was laminar with parallel streamlines, but strong vortices developed simultaneous with expansion of the cushions and septal walls. For all investigated stages, highest wall shear stresses (WSS) are localized to AV canal valve-forming regions. Peak WSS increased from 19.34 dynes/cm(2) at HH17 to 287.18 dynes/cm(2) at HH30, but spatiotemporally averaged WSS became 3.62 dynes/cm(2) for HH17 to 9.11 dynes/cm(2) for HH30. Hemodynamic changes often preceded and correlated with morphological changes. These results establish a quantitative baseline supporting future hemodynamic analyses and interpretations.


Assuntos
Aves/embriologia , Padronização Corporal/fisiologia , Circulação Coronária/fisiologia , Valvas Cardíacas/embriologia , Hemodinâmica/fisiologia , Animais , Pressão Sanguínea/fisiologia , Embrião de Galinha , Simulação por Computador , Diástole/fisiologia , Valvas Cardíacas/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Ultrassonografia , Estudos de Validação como Assunto , Microtomografia por Raio-X
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