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1.
Metab Brain Dis ; 38(1): 307-321, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36305999

RESUMO

Both type-1 and type-2 DM are related to an increased risk of cognitive impairment, neurovascular complications, and dementia. The primary triggers for complications are hyperglycemia and concomitant insulin resistance in type-2 DM. However, the diverse mechanisms in the pathogenesis of diabetes-related neurovascular complications and extracellular matrix (ECM) remodeling in type-1 and 2 have not been elucidated yet. Here, we investigated the high fat-high sucrose (HFHS) feeding model and streptozotocin-induced type-1 DM model to study the early effects of hyperglycemia with or without insulin resistance to demonstrate the brain microcirculatory changes, perivascular ECM alterations in histological sections and 3D-reconstructed cleared brain tissues. One of the main findings of this study was robust rarefaction in brain microvessels in both models. Interestingly, the HFHS model leads to widespread non-functional angiogenesis, but the type-1 DM model predominantly in the rostral brain. Rarefaction was accompanied by basement membrane thickening and perivascular collagen accumulation in type-1 DM; more severe blood-brain barrier leakage, and disruption of perivascular ECM organization, mainly of elastin and collagen fibers' structural integrity in the HFHS model. Our results point out that the downstream mechanisms of the long-term vascular complications of hyperglycemia models are structurally distinctive and may have implications for appropriate treatment options.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Resistência à Insulina , Humanos , Microcirculação , Encéfalo/patologia , Hiperglicemia/patologia , Diabetes Mellitus Tipo 2/patologia
2.
Adv Sci (Weinh) ; 9(27): e2201294, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35896894

RESUMO

Soluble ACE2 (sACE2) decoys are promising agents to inhibit SARS-CoV-2, as their efficiency is unlikely to be affected by escape mutations. However, their success is limited by their relatively poor potency. To address this challenge, multimeric sACE2 consisting of SunTag or MoonTag systems is developed. These systems are extremely effective in neutralizing SARS-CoV-2 in pseudoviral systems and in clinical isolates, perform better than the dimeric or trimeric sACE2, and exhibit greater than 100-fold neutralization efficiency, compared to monomeric sACE2. SunTag or MoonTag fused to a more potent sACE2 (v1) achieves a sub-nanomolar IC50 , comparable with clinical monoclonal antibodies. Pseudoviruses bearing mutations for variants of concern, including delta and omicron, are also neutralized efficiently with multimeric sACE2. Finally, therapeutic treatment of sACE2(v1)-MoonTag provides protection against SARS-CoV-2 infection in an in vivo mouse model. Therefore, highly potent multimeric sACE2 may offer a promising treatment approach against SARS-CoV-2 infections.


Assuntos
Enzima de Conversão de Angiotensina 2 , Tratamento Farmacológico da COVID-19 , Animais , Anticorpos Monoclonais/uso terapêutico , Camundongos , SARS-CoV-2
3.
Placenta ; 115: 12-19, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34534911

RESUMO

INTRODUCTION: In preeclampsia (PE), human decidua mesenchymal stromal cells (hDMSCs) are exposed to abnormally high levels of oxidative stress and inflammatory factors circulating in the maternal blood. MicroRNAs (miRNAs) have been shown to have a significant impact on the differentiation, maturation and function of mesenchymal stromal cells (MSCs). Our aim in the present study is firstly to investigate differentially expressed miRNA levels to be used as a biomarker in the early detection of PE and secondly to investigate whether those differentially expressed miRNAs in hDMSCs have an effect on the pathogenesis of PE. METHODS: This study covers miRNA expression analysis of hDMSCs from 7 PE patient and 7 healthy pregnant women and is a preliminary study to investigate putative biomarkers. After cell culture and cell sorting, total RNA including miRNAs were isolated from hDMSCs. Let-7b-3p, let-7f-1-3p, miR-191-3p, miR-550a-5p, miR-33b-3p and miR-425-3p were used for miRNA analysis and U6 snRNA was used for normalization of the samples. MiRNA analysis was performed by droplet digital polymerase chain reaction (ddPCR) method and obtained results were evaluated statistically. RESULTS: As a result of the analysis, it was observed that the levels of hsa-miR-33b-3p significantly (AUC: 0.93, p = 0.04, fold change: 4.5) increased in hDMSC of PE patients compared to healthy controls. However, let-7b-3p, let-7f-1-3p, miR-191-3p, miR-550a-5p, and miR-425-3p were not considered as significant because they did not meet the p < 0,05 requirement. DISCUSSION: Within the scope of the study, it is predicted that miR-33b-3p (p = 0.004, AUC = 0.93) can be used as a biomarker in detecting PE.


Assuntos
Decídua/citologia , Células-Tronco Mesenquimais/química , MicroRNAs/análise , Adulto , Cesárea , Feminino , Humanos , Reação em Cadeia da Polimerase/métodos , Pré-Eclâmpsia , Gravidez , Fator de Crescimento Transformador beta/genética
4.
Metab Brain Dis ; 36(8): 2553-2566, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34118020

RESUMO

Hypertension (HT) is one of the main causes of vascular dementia, lead to cognitive decline. Here, we investigated the relationship between cerebral microvessels, pericytes, extracellular matrix (ECM) accumulation, blood-brain barrier (BBB) breakdown, and memory impairment at mid-life in a chronic hypertension animal model. Spontaneously hypertensive rats (SHRs) (n = 20) are chosen for the model and age matched Wistar rats (n = 16) as controls. Changes in brain microvasculature and in vitro experiments are shown with immunofluorescence studies and cognition with open field, novel object recognition, and Y maze tests. There was a significant reduction in pericyte coverage in SHRs (p = 0.021), while the quantitative parameters of the cerebral microvascular network were not different between groups. On the other hand, parenchymal albumin leakage, as a Blood-brain barrier (BBB) breakdown marker, was prominent in SHRs (p = 0.023). Extracellular matrix (ECM) components, collagen type 1, 3 and 4 were significantly increased (accumulated) around microvasculature in SHRs (p = 0.011, p = 0.013, p = 0.037, respectively). Furthermore, in vitro experiments demonstrated that human brain vascular pericytes but not astrocytes and endothelial cells secreted type I collagen upon TGFß1 exposure pointing out a possible role of pericytes in increased collagen accumulation around cerebral microvasculature due to HT. Furthermore, valsartan treatment decreased the amount of collagen type 1 secreted by pericytes after TGFß1 exposure. At the time of evaluation, SHRs did not demonstrate cognitive decline and memory impairments. Our results showed that chronic HT causes ECM accumulation and BBB leakage before leading to memory impairments and therefore, pericytes could be a novel target for preventing vascular dementia.


Assuntos
Barreira Hematoencefálica , Hipertensão , Animais , Barreira Hematoencefálica/metabolismo , Colágeno/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Microvasos/metabolismo , Ratos , Ratos Wistar
5.
Biology (Basel) ; 10(5)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34068937

RESUMO

We proposed the hypothesis that high-risk clones of colistin-resistant K. pneumoniae (ColR-Kp) possesses a high number of virulence factors and has enhanced survival capacity against the neutrophil activity. We studied virulence genes of ColR-Kp isolates and neutrophil response in 142 patients with invasive ColR-Kp infections. The ST101 and ST395 ColR-Kp infections had higher 30-day mortality (58%, p = 0.005 and 75%, p = 0.003). The presence of yersiniabactin biosynthesis gene (ybtS) and ferric uptake operon associated gene (kfu) were significantly higher in ST101 (99%, p ≤ 0.001) and ST395 (94%, p < 0.012). Being in ICU (OR: 7.9; CI: 1.43-55.98; p = 0.024), kfu (OR:27.0; CI: 5.67-179.65; p < 0.001) and ST101 (OR: 17.2; CI: 2.45-350.40; p = 0.01) were found to be predictors of 30-day mortality. Even the neutrophil uptake of kfu+-ybtS+ ColR-Kp was significantly higher than kfu--ybtS- ColR-Kp (phagocytosis rate: 78% vs. 65%, p < 0.001), and the kfu+-ybtS+ ColR-Kp survived more than kfu--ybtS- ColR-Kp (median survival index: 7.90 vs. 4.22; p = 0.001). The kfu+-ybtS+ ColR-Kp stimulated excessive NET formation. Iron uptake systems in high-risk clones of colistin-resistant K. pneumoniae enhance the success of survival against the neutrophil phagocytic defense and stimulate excessive NET formation. The drugs targeted to iron uptake systems would be a promising approach for the treatment of colistin-resistant high-risk clones of K. pneumoniae infections.

6.
J Plast Reconstr Aesthet Surg ; 74(10): 2751-2758, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33935009

RESUMO

An intriguing observation that has recently found support through clinical and experimental studies is that wounds of the oral mucosa tend to display faster healing and result in less scarring than in the skin. We aimed to investigate the potential of heterotopic oral mucosal fibroblasts in cutaneous wounds while determining the main differences between wounds conditioned with either the oral mucosa or dermis-derived human fibroblasts. A total of 48 nude mice were divided into four groups: control, sham, dermal fibroblast (DF), and oral fibroblast (OF). Fibroblasts were isolated, cultured, and seeded onto fibrin scaffolds for transfer to full-thickness dorsal wounds. Cell viability, wound area, healing rate, vascularization, cellular proliferation, dermal thickness, collagen architecture, and subtypes were evaluated. Both cell groups had a viability of 95% in fibrin gel prior to transfer. None of the wounds fully epithelialized on day 10, while all were epithelialized by day 21, which resulted in scars of different sizes and quality. Healing rate and scars were similar between the control and sham groups, whereas fastest healing and least scarring were noted in the OF group. Dermal thickness was highest in the DF group, which was also supported by highest levels of collagen types I and III. Proliferative cells and vascular density were highest in the OF group. DF result in healing through a thick dermal component, while oral fibroblasts result in faster healing and less scarring through potentially privileged angiogenic and regenerative gene expression.


Assuntos
Derme/citologia , Fibroblastos/fisiologia , Mucosa Bucal/citologia , Reepitelização , Animais , Proliferação de Células , Sobrevivência Celular , Cicatriz/patologia , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Derme/lesões , Fibrina , Fibroblastos/transplante , Géis , Humanos , Camundongos , Neovascularização Fisiológica
7.
Crit Rev Oncog ; 26(4): 37-53, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35381146

RESUMO

Physiology of the mammalian body has been adapted to diurnal cycles of around 24 h, an evolutionary situation that affects a wide spectrum of biological events including sleep-to-wake transitions, feeding/fasting, body temperature, and hormonal regulations. The patterns of the diurnal cycle occur due to rhythmic oscillations that arise from the suprachiasmatic nucleus of hypothalamus, which also can be defined as the pacemaker of the system. The clock can be defined as a molecular machinery driven by the core clock genes that encode clock proteins in a rhythmic oscillatory fashion maintained by the light/dark cycles of the environment. Although the well-established knowledge refers to the function of the circadian rhythm as maintenance of the normal physiology, growing evidence shows that disruptions in the system usually caused by genetic and/or epigenetic misregulations may have a direct effect to lead major pathological conditions, such as carcinogenesis. This review outlines the main molecular aspects of circadian physiology, and reveals the reasons for and results of the circadian disruptions at different levels. In spite of the fact that more proof is needed for a direct correlation between circadian disruptions and oncogenesis and other pathological events, data obtained from current research supports the role of circadian rhythms in malfunctioning of the normal cellular metabolism.


Assuntos
Relógios Circadianos , Animais , Relógios Circadianos/genética , Ritmo Circadiano/genética , Humanos , Mamíferos/genética , Sono , Núcleo Supraquiasmático/metabolismo
8.
J Neurochem ; 156(6): 848-866, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32939791

RESUMO

This study aimed to investigate and compare cell growth manners and functional differences of primary cortical neurons cultured on either poly-d-lysine (PDL) and or Matrigel, to delineate the role of extracellular matrix on providing resemblance to in vivo cellular interactions in nervous tissue. Primary cortical neurons, obtained from embryonic day 15 mice pups, seeded either on PDL- or Matrigel-coated culture ware were investigated by DIC/bright field and fluorescence/confocal microscopy for their morphology, 2D and 3D structure, and distribution patterns. Patch clamp, western blot, and RT-PCR studies were performed to investigate neuronal firing thresholds and sodium channel subtypes Nav1.2 and Nav1.6 expression. Cortical neurons cultured on PDL coating possessed a 2D structure composed of a few numbers of branched and tortuous neurites that contacted with each other in one to one manner, however, neurons on Matrigel coating showed a more complicated dimensional network that depicted tight, linear axonal bundles forming a 3D interacted neuron-astrocyte construction. This difference in growth patterns also showed a significant alteration in neuronal firing threshold which was recorded between 80 < Iinj > 120 pA on PDL and 2 < Iinj > 160 pA on Matrigel. Neurons grown up on Matrigel showed increased levels of sodium channel protein expression of Nav1.2 and Nav1.6 compared to neurons on PDL. These results have demonstrated that a 3D interacted neuron-astrocyte construction on Matrigel enhances the development of Nav1.2 and Nav1.6 in vitro and decreases neuronal firing threshold by 40 times compared to conventional PDL, resembling in vivo neuronal networks and hence would be a better in vitro model of adult neurons.


Assuntos
Astrócitos/fisiologia , Astrócitos/ultraestrutura , Colágeno , Laminina , Neurônios/fisiologia , Neurônios/ultraestrutura , Proteoglicanas , Canais de Sódio Disparados por Voltagem/biossíntese , Animais , Córtex Cerebral/citologia , Combinação de Medicamentos , Fenômenos Eletrofisiológicos , Embrião de Mamíferos/fisiologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Canal de Sódio Disparado por Voltagem NAV1.2/biossíntese , Canal de Sódio Disparado por Voltagem NAV1.2/genética , Canal de Sódio Disparado por Voltagem NAV1.6/biossíntese , Canal de Sódio Disparado por Voltagem NAV1.6/genética , Neuritos/fisiologia , Técnicas de Patch-Clamp , Gravidez , Cultura Primária de Células
9.
Cell Death Discov ; 6(1): 93, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042587

RESUMO

Molecular mechanisms underlying luteinization (terminal differentiation of granulosa and theca cells after ovulation) and luteolysis (demise of corpus luteum) are poorly understood in human ovary. Here we report that activin-A, after binding to its cognate receptors induces a functional luteolytic state and reverses luteinization phenotype by downregulating the expression of the steroidogenic enzymes, LH receptor and VEGF and reducing estradiol (E2) progesterone (P4) production and upregulating FSH receptor and cyclin D1 expression in human primary luteinized granulosa cells. Further, this action of activin-A involves downregulation of JNK signaling pathway and is opposite to that of human chorionic gonadotropin (hCG), which acts as a luteotropic hormone and improves luteal function through the activation of JNK pathway in the same cell type. Reversal of luteinization phenotype in luteal granulosa cells by activin-A potentially makes this hormone an attractive candidate for use under certain clinical situations, where induction of luteolysis and rapid reduction of endogenous sex steroid levels are beneficial such as ovarian hyperstimulation syndrome (OHSS), in which the ovaries hyper-respond to gonadotropin stimulation by producing too many growing follicles along with development of ascites, pleural effusion, and hemo-concentrations as a result of increased vascular permeability and leakage of intravascular volume into third spaces. Our work unveils a previously undefined role for activin-A and JNK signaling pathway in human corpus luteum biology, that might have a direct clinical impact in assisted reproductive technologies.

10.
Am J Physiol Heart Circ Physiol ; 318(5): H1208-H1218, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32243769

RESUMO

In the embryonic heart, blood flow is distributed through a bilaterally paired artery system composed of the aortic arches (AAs). The purpose of this study is to establish an understanding of the governing mechanism of microstructural maturation of the AA matrix and its reversibility, toward the desired macroscopic vessel lumen diameter and thickness for healthy, abnormal, and in ovo repaired abnormal mechanical loading. While matrix-remodeling mechanisms were significantly different for normal versus conotruncal banding (CTB), both led to an increase in vessel lumen. Correlated with right-sided flow increase at Hamburger & Hamilton stages 21, intermittent load switching between collagen I and III with elastin and collagen-IV defines the normal process. However, decreases in collagen I, elastin, vascular endothelial growth factor-A, and fibrillin-1 in CTB were recovered almost fully following the CTB-release model, primarily because of the pressure load changes. The complex temporal changes in matrix proteins are illustrated through a predictive finite-element model based on elastin and collagen load-sharing mechanism to achieve lumen area increase and thickness increase resulting from wall shear stress and tissue strain, respectively. The effect of embryonic timing in cardiac interventions on AA microstructure was established where abnormal mechanical loading was selectively restored at the key stage of development. Recovery of the normal mechanical loading via early fetal intervention resulted in delayed microstructural maturation. Temporal elastin increase, correlated with wall shear stress, is required for continuous lumen area growth.NEW & NOTEWORTHY The present study undertakes comparative analyses of the mechanistic differences of the arterial matrix microstructure and dynamics in the three fundamental processes of control, conotruncal banded, and released conotruncal band in avian embryo. Among other findings, this study provides specific evidence on the restorative role of elastin during the early lumen growth process. During vascular development, a novel intermittent load-switching mechanism between elastin and collagen, triggered by a step increase in wall shear stress, governs the chronic vessel lumen cross-sectional area increase. Mimicking the fetal cardiovascular interventions currently performed in humans, the early release of the abnormal mechanical load rescues the arterial microstructure with time lag.


Assuntos
Aorta Torácica/embriologia , Hemodinâmica , Estresse Mecânico , Animais , Aorta Torácica/metabolismo , Aorta Torácica/fisiologia , Aorta Torácica/ultraestrutura , Embrião de Galinha , Colágeno/metabolismo , Circulação Coronária , Elastina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
In Vitro Cell Dev Biol Anim ; 55(7): 473-481, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31214928

RESUMO

Leptin, a metabolic hormone, regulates the reproductive functions responding to both nutritional and body conditions. Embryonic stem cells play important roles in reproductive technology, but their derivation can be challenging. In this study, we evaluated the derivation rates of mouse embryonic stem cell (mESC) line from blastocysts developing in embryo culture media supplemented with different leptin concentrations. The results showed that addition of leptin into the embryo culture medium supported the in vitro development of mouse embryo. The mESC line derivation rates for media treated with 0, 10, 50, and 100 ng/ml of leptin were 61.24 % (54/88), 84.96 % (42/50), 81.79 % (61/76), and 85.78 % (56/67), respectively. In addition, leptin treatment of blastocysts upregulated the expression levels of the trophectoderm marker Cdx2, whereas inner cell mass markers Oct-4 and Nanog were not affected. mESC lines derived after leptin treatment demonstrated hallmarks of pluripotency, such as alkaline phosphatase activity, expression of, OCT4, NANOG, and SSEA1, as well as the ability to form embryoid bodies and well-differentiated teratomas. In conclusion, leptin has a positive effect on the derivation rate of mouse embryonic stem cell lines which may be, in part, due to its effects on the development of the trophectoderm cell lineage in the embryo.


Assuntos
Blastocisto/citologia , Proliferação de Células/efeitos dos fármacos , Leptina/farmacologia , Células-Tronco Embrionárias Murinas/citologia , Teratoma/metabolismo , Animais , Fator de Transcrição CDX2/biossíntese , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Linhagem da Célula , Meios de Cultura/farmacologia , Técnicas de Cultura Embrionária , Corpos Embrioides/citologia , Antígenos CD15/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteína Homeobox Nanog/biossíntese , Fator 3 de Transcrição de Octâmero/biossíntese , Teratoma/induzido quimicamente
12.
Brain Res ; 1715: 148-155, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30914250

RESUMO

The blood-brain barrier (BBB) permeability primarily increases in cerebral venules during acute hypertension. Methyl-ß-cyclodextrin (MßCD), a cholesterol-depleting agent, decreases the expression of caveolins disrupting caveolar structures. We aimed to determine the effects of MßCD on the BBB permeability of angiotensin (ANG) II-induced hypertensive rats. Three minutes after MßCD administration (5 mg/kg), acute hypertension was induced by ANG II (60 µg/kg). Evans blue (EB) and horseradish peroxidase (HRP) tracers were used to assess BBB permeability. Immunohistochemistry for caveolin (Cav)-1 and tight junction protein claudin-5 was performed. EB dye content significantly increased in both cerebral cortices and left hippocampus in MßCD (P < 0.05), right cerebral cortex and both hippocampi in ANG II (P < 0.05; P < 0.01), and both cerebral cortices and hippocampi in MßCD plus ANG II groups compared with controls (P < 0.05; P < 0.01). A significant decrease in claudin-5 immunostaining intensity was observed in animals treated with MßCD compared with controls (P < 0.05). Cav-1 immunostaining intensity increased in ANG II group (P < 0.05). Ultrastructurally, HRP reaction products were observed in endothelial cells of the microvessels in the hippocampus region in MßCD group while the tracer was mainly localized in astrocytes and neurons in ANG II, and MßCD plus ANG II groups. The endothelial cells of the venules in the cerebral cortex of the animals in the latter experimental groups also showed an abundance of caveolar vesicles devoid of HRP reaction products. Our results revealed that MßCD did not provide overall protective effects on BBB integrity in acute hypertension and even led to BBB disruption in normotensive animals.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , beta-Ciclodextrinas/farmacologia , Angiotensina II/farmacologia , Animais , Astrócitos/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Caveolina 1/metabolismo , Córtex Cerebral/metabolismo , Claudina-5/metabolismo , Células Endoteliais/metabolismo , Hipocampo/metabolismo , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Masculino , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , beta-Ciclodextrinas/metabolismo
13.
Cell Death Discov ; 5: 64, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30774992

RESUMO

Harakiri (HRK) is a BH3-only protein of the Bcl-2 family and regulates apoptosis by interfering with anti-apoptotic Bcl-2 and Bcl-xL proteins. While its function is mainly characterized in the nervous system, its role in tumors is ill-defined with few studies demonstrating HRK silencing in tumors. In this study, we investigated the role of HRK in the most aggressive primary brain tumor, glioblastoma multiforme (GBM). We showed that HRK is differentially expressed among established GBM cell lines and that HRK overexpression can induce apoptosis in GBM cells at different levels. This phenotype can be blocked by forced expression of Bcl-2 and Bcl-xL, suggesting the functional interaction of Bcl-2/Bcl-xL and HRK in tumor cells. Moreover, HRK overexpression cooperates with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a known tumor-specific pro-apoptotic agent. Besides, secondary agents that augment TRAIL response, such as the histone deacetylase inhibitor MS-275, significantly increases HRK expression. In addition, GBM cell response to TRAIL and MS-275 can be partly abolished by HRK silencing. Finally, we showed that HRK induction suppresses tumor growth in orthotopic GBM models in vivo, leading to increased survival. Taken together, our results suggest that HRK expression is associated with GBM cell apoptosis and increasing HRK activity in GBM tumors might offer new therapeutic approaches.

14.
Cell Death Dis ; 9(10): 943, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30237472

RESUMO

There is a controversy in literature as to whether c-Abl is crucial for the induction of TAp63-mediated apoptosis and whether that inhibition of c-Abl with imatinib, which was designed to inhibit the oncogenic kinase BCR-ABL and c-kit, protects oocytes from chemotherapy-induced apoptosis in mice. No human data are available on this issue. We therefore aimed to explore whether genomic damage induced by chemotherapy drug cisplatin activates c-Abl along with TAp63 and the inhibition of c-Abl with imatinib prevents cisplatin-induced oocyte death and follicle loss in human ovary. Exposure to cisplatin induced DNA damage, activated TAp63 and SAPK/JNK pathway, and triggered apoptosis in the oocytes and granulosa cells. However, TAp63 activation after cisplatin was not associated with any increase in the expression of c-Abl. Imatinib did not prevent cisplatin-induced apoptosis of the granulosa cells or oocytes. Moreover, treatment with this drug resulted in the formation of bizarre shaped follicles lacking oocytes and increased follicular atresia by inducing apoptosis of granulosa cells and oocytes. Similar toxic effects were observed when ovarian tissue samples were incubated with a c-kit antagonist drug anti-CD117, but not with another c-Abl tyrosine kinase inhibitor GNF-2, which lacks an inhibitory action on c-kit. Intraperitoneal administration of imatinib to the xenografted animals produced similar histomorphological abnormalities in the follicles in human ovarian grafts and did not prevent cisplatin-induced follicle loss when co-administered with cisplatin. Our findings provide, for the first time, a molecular evidence for ovarian toxicity of this drug in human. Furthermore, this study together with two previous case reports of a severely compromised ovarian response to gonadotropin stimulation and premature ovarian failure in patients, while receiving imatinib, further heighten the concerns about its potential gonadotoxicity on human ovary and urge caution in its use in young female patients.


Assuntos
Dano ao DNA/genética , Genes abl/fisiologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/uso terapêutico , Dano ao DNA/efeitos dos fármacos , Feminino , Genes abl/genética , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Humanos , Mesilato de Imatinib/uso terapêutico , Immunoblotting , Injeções Intraperitoneais , Camundongos , Camundongos Nus , Oócitos/citologia , Oócitos/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Ovário/efeitos dos fármacos , Ovário/metabolismo , Insuficiência Ovariana Primária/tratamento farmacológico , Insuficiência Ovariana Primária/metabolismo , Técnicas de Cultura de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Cell Death Dis ; 9(4): 421, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29549247

RESUMO

Granulosa cell tumor of the ovary (GCT) is a very rare tumor, accounting for only 2% of all ovarian tumors. It originates from sex cords in the ovary and can be divided into adult (95%) and juvenile (5%) types based on histologic findings. To date, no clear etiologic process has been identified other than a missense point mutation in the FOXL2 gene. Our previous works showed that c-Jun N-terminal kinase (JNK) pathway plays critical role in cell cycle progression and mitosis of normal and immortalized granulosa cells and follicle growth in rodent ovaries. These findings led us to investigate the role of JNK pathway in the granulosa cell tumor of the ovary. We used two different GCT cell lines (COV434 and KGN) and fresh GCT samples of adult and juvenile types obtained from the patients during surgery. We have discovered that endogenous kinase activity of JNK is markedly enhanced in the GCT samples and cell lines, whereas it was almost undetectable in mitotic non-malignant human granulosa cells. The inhibition of JNK pathway in GCT cell lines with two different pharmacologic inhibitors (SP600125 and AS601245) or siRNA resulted in a dose-dependent reduction in in vitro cell growth, increased apoptosis and diminished estradiol and AMH productions. JNK inhibition was also associated with a decrease in the number of cells positive for mitosis marker phospho-histone H3Ser 10 in the asynchronous cells; and diminished EdU uptake during S phase and cell cycle arrest at G2/M-phase transition in the synchronized cells. Ex vivo treatment of patient-derived GCT samples with JNK inhibitors for 24 h significantly decreased their in vitro growth and estradiol and AMH productions. Furthermore, in human GCT xenograft model, in vivo tumor growth was significantly reduced and plasma AMH levels were significantly decreased in SCID mice after administration of JNK inhibitors and siRNA. These findings suggest that targeting JNK pathway may provide therapeutic benefit in the treatment of granulosa cell tumors for which currently no curative therapy exists beyond surgery.


Assuntos
Tumor de Células da Granulosa/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Ovarianas/patologia , Acetonitrilas/farmacologia , Acetonitrilas/uso terapêutico , Animais , Antracenos/farmacologia , Antracenos/uso terapêutico , Hormônio Antimülleriano/sangue , Hormônio Antimülleriano/metabolismo , Apoptose/efeitos dos fármacos , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Estradiol/metabolismo , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Tumor de Células da Granulosa/tratamento farmacológico , Tumor de Células da Granulosa/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Camundongos , Camundongos SCID , Mitose , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
Acta Histochem ; 120(2): 117-121, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29325972

RESUMO

PURPOSE: Sperm processing (e.g., centrifugation) used in preparation for assisted reproduction can result in excessive generation of reactive oxygen species (ROS) and potential sperm damage. The use of antioxidants during sperm processing has been shown to prevent iatrogenic sperm damage, including DNA damage. In this study, we evaluated the effect of caffeic acid phenethyl ester (CAPE) on oxidative stress mediated sperm dysfunction and DNA damage. METHODS: Semen samples were obtained to liquefy at room temperature. After centrifugation and washing protocols, spermatozoa were incubated in a single step supplemented medium with either of 10, 50 or 100 µmol/L CAPE for 2 hours at 36 °C. After incubation period, MDA levels of seminal plasma were measured. The fragmentation in sperm DNA was detected by light microscopy via use of an aniline blue assay, while ultrastructural morphology was analyzed by transmission electron microscopy. RESULTS: Significant increase has been observed in percent chromatin condensation (assessed by aniline blue staining) and Malondialdehyde (Mmol/L) in oligoasthenoteratozoospermia group before the centrifugation (0.57 ±â€¯0.15). Incubation of samples with 100 µmol/L CAPE after centrifugation resulted in a significantly lower percent chromatin condensation compared to samples incubated without CAPE (0.42 ±â€¯0.12) (P < 0.0033). Incubation of all samples with CAPE (10 µmol/L, 50 µmol/L, 100 µmol/L.) after centrifugation resulted in a significantly lower percentage of Malondialdehyde levels. CONCLUSIONS: The data suggests that preincubation of spermatozoa with the antioxidant CAPE offers protection against oxidative DNA damage in vitro.


Assuntos
Antioxidantes/farmacologia , Ácidos Cafeicos/farmacologia , Álcool Feniletílico/análogos & derivados , Espermatozoides/efeitos dos fármacos , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/efeitos dos fármacos , Álcool Feniletílico/farmacologia , Análise do Sêmen
17.
Cell Death Dis ; 8(6): e2897, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28661478

RESUMO

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively kill tumor cells. TRAIL resistance in cancers is associated with aberrant expression of the key components of the apoptotic program. However, how these components are regulated at the epigenetic level is not understood. In this study, we investigated novel epigenetic mechanisms regulating TRAIL response in glioblastoma multiforme (GBM) cells by a short-hairpin RNA loss-of-function screen. We interrogated 48 genes in DNA and histone modification pathways and identified KDM2B, an H3K36-specific demethylase, as a novel regulator of TRAIL response. Accordingly, silencing of KDM2B significantly enhanced TRAIL sensitivity, the activation of caspase-8, -3 and -7 and PARP cleavage. KDM2B knockdown also accelerated the apoptosis, as revealed by live-cell imaging experiments. To decipher the downstream molecular pathways regulated by KDM2B, levels of apoptosis-related genes were examined by RNA-sequencing upon KDM2B loss, which revealed derepression of proapoptotic genes Harakiri (HRK), caspase-7 and death receptor 4 (DR4) and repression of antiapoptotic genes. The apoptosis phenotype was partly dependent on HRK upregulation, as HRK knockdown significantly abrogated the sensitization. KDM2B-silenced tumors exhibited slower growth in vivo. Taken together, our findings suggest a novel mechanism, where the key apoptosis components are under epigenetic control of KDM2B in GBM cells.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteínas F-Box/genética , Glioblastoma/genética , Histona Desmetilases com o Domínio Jumonji/genética , RNA Interferente Pequeno/genética , Apoptose/genética , Caspase 7/genética , Linhagem Celular Tumoral , Metilação de DNA/genética , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Glioblastoma/patologia , Código das Histonas/genética , Humanos , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem , Ligante Indutor de Apoptose Relacionado a TNF/genética
18.
J Obstet Gynaecol ; 37(4): 492-497, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28421902

RESUMO

To evaluate the role of ovarian reserve markers in the prediction of clinical pregnancy and embryo transfer accomplishment among poor responder IVF applicants. 304 female poor responder IVF applicants were included in this prospective cohort study conducted at the IVF-unit. Antral follicle count, FSH, LH, E2, AMH and IVF outcomes were compared in pregnant and non-pregnant groups as well as in ET vs. non-ET groups. The number of retrieved oocytes was significantly correlated positively with AMH and AFC, and negatively with FSH and age. Quartiles of FSH and AFC were similar to the rate of pregnancy. Quartiles of AMH (<25%/25-75% and <25%/>75%) were statistically significant. Mean serum levels for AMH were significantly lower in the non-ET group. Our findings seem to indicate that day 3 AMH values can predict ET accomplishment with a sensitivity of 96% and a specificity of 35%. Quartiles of AMH <25% (< 0.21 ng/mL) can predict the IVF results among poor responder IVF applicants. Impact statement Various cut-off values have been determined for day 3 serum AMH values. These values help to determine the groups that are expected to give normal, high or low response to stimulation and decide the treatment options. In contrast to other groups of patients, poor responders cannot reach the embryo transfer stage for several reasons. These are; absence of a mature oocyte after oocyte pick-up, fertilisation failure without male factor or poor embryo quality. In the present study; a cut-off value of 0.33 ng/mL for the prediction of ET accomplishment in poor responder patients was determined with a sensitivity of 96%. Additionally, clinical pregnancy could not be achieved under the value of 0.21 ng/mL day 3 AMH values. It is important to clarify the embryo transfer success of poor responder patients prior to expected treatment success. Pre-treatment counselling for these patients would lessen the disappointment that may develop after treatment. The cost-effectiveness of treatments below these AMH values can be determined by further studies.


Assuntos
Hormônio Antimülleriano/sangue , Transferência Embrionária , Hormônio Foliculoestimulante/sangue , Reserva Ovariana/fisiologia , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Infertilidade Feminina/sangue , Recuperação de Oócitos , Oócitos/crescimento & desenvolvimento , Gravidez , Taxa de Gravidez , Curva ROC , Reprodutibilidade dos Testes , Resultado do Tratamento
19.
J Chem Neuroanat ; 77: 93-99, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27262783

RESUMO

An imbalance between GABAergic inhibition and glutamatergic excitation is suspected to play a role in the genesis of epileptic processes. In the present study we quantified the number of glutamate+ve neurons in the mediodorsal thalamic nucleus (MD) of genetic absence epilepsy rats from Strasbourg (GAERS) and compared these with values for normal Wistar rats. The MD thalamic nucleus was removed from each animal and the glutamatergic neurons were labelled using light-microscopy glutamate immunohistochemistry. The disector method was used to quantify the glutamate+ve neurons in the MD thalamic nucleus of GAERS and Wistar rats. The data were statistically analyzed. In the Wistar animals glutamate+ve neurons formed 89% and in GAERS 92.3% of the total neurons in 1000µm3 of MD thalamic nucleus. In GAERS glutamate+ve neurons showed statistically significant increase in the MD thalamic nucleus compared to Wistar animals. In Wistar animals the glutamate-ve neurons formed 11% and in GAERS 7.7% of the total neurons in 1000µm3 of MD thalamic. No significant difference was observed in glutamate-ve neurons between the two strains. The average diameter of glutamate+ve neurons showed no significance, while glutamate-ve neurons were significant between the two strains. The results of the present study, on genetic absence epilepsy model, GAERS, confirms the role of MD thalamic nucleus in chemically induced absence epilepsy.


Assuntos
Epilepsia Tipo Ausência/patologia , Ácido Glutâmico/fisiologia , Núcleo Mediodorsal do Tálamo/patologia , Animais , Contagem de Células , Epilepsia Tipo Ausência/genética , Imuno-Histoquímica , Masculino , Neurônios/patologia , Neurônios/ultraestrutura , Ratos , Ratos Wistar
20.
Clin Epigenetics ; 8: 48, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27152124

RESUMO

BACKGROUND: Chronic hepatitis B infection is characterized by hepatic immune and inflammatory response with considerable variation in the rates of progression to cirrhosis. Genetic variants and environmental cues influence predisposition to the development of chronic liver disease; however, it remains unknown if aberrant DNA methylation is associated with fibrosis progression in chronic hepatitis B. RESULTS: To identify epigenetic marks associated with inflammatory and fibrotic processes of the hepatitis B-induced chronic liver disease, we carried out hepatic genome-wide methylation profiling using Illumina Infinium BeadArrays comparing mild and severe fibrotic disease in a discovery cohort of 29 patients. We obtained 310 differentially methylated regions and selected four loci comprising three genes from the top differentially methylated regions: hypermethylation of HOXA2 and HDAC4 along with hypomethylation of PPP1R18 were significantly linked to severe fibrosis. We replicated the prominent methylation marks in an independent cohort of 102 patients by bisulfite modification and pyrosequencing. The timing and causal relationship of epigenetic modifications with disease severity was further investigated using a cohort of patients with serial biopsies. CONCLUSIONS: Our findings suggest a linkage of widespread epigenetic dysregulation with disease progression in chronic hepatitis B infection. CpG methylation at novel genes sheds light on new molecular pathways, which can be potentially exploited as a biomarker or targeted to attenuate inflammation and fibrosis.


Assuntos
Metilação de DNA , Marcadores Genéticos/genética , Hepatite B Crônica/genética , Cirrose Hepática/genética , Cirrose Hepática/patologia , Adulto , Idoso , Progressão da Doença , Epigênese Genética , Feminino , Histona Desacetilases/genética , Proteínas de Homeodomínio/genética , Humanos , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Proteína Fosfatase 1/genética , Proteínas Repressoras/genética
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