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1.
Artigo em Inglês | MEDLINE | ID: mdl-38606576

RESUMO

OBJECTIVE: Paragangliomas of the urinary bladder (UBPGLs) are rare neuroendocrine tumours and pose a diagnostic and surgical challenge. It remains unclear what factors contribute to a timely presurgical diagnosis. The purpose of this study is to identify factors contributing to missing the diagnosis of UBPGLs before surgery. DESIGN, PATIENTS AND MEASUREMENTS: A total of 73 patients from 11 centres in China, and 51 patients from 6 centres in Europe and 1 center in the United States were included. Clinical, surgical and genetic data were collected and compared in patients diagnosed before versus after surgery. Logistic regression analysis was used to identify clinical factors associated with initiation of presurgical biochemical testing. RESULTS: Among all patients, only 47.6% were diagnosed before surgery. These patients were younger (34.0 vs. 54.0 years, p < .001), had larger tumours (2.9 vs. 1.8 cm, p < .001), and more had a SDHB pathogenic variant (54.7% vs. 11.9%, p < .001) than those diagnosed after surgery. Patients with presurgical diagnosis presented with more micturition spells (39.7% vs. 15.9%, p = .003), hypertension (50.0% vs. 31.7%, p = .041) and catecholamine-related symptoms (37.9% vs. 17.5%, p = .012). Multivariable logistic analysis revealed that presence of younger age (<35 years, odds ratio [OR] = 6.47, p = .013), micturition spells (OR = 6.79, p = .007), hypertension (OR = 3.98, p = .011), and sweating (OR = 41.72, p = .013) increased the probability of initiating presurgical biochemical testing. CONCLUSIONS: Most patients with UBPGL are diagnosed after surgery. Young age, hypertension, micturition spells and sweating are clues in assisting to initiate early biochemical testing and thus may establish a timely presurgical diagnosis.

2.
Horm Metab Res ; 56(1): 8-9, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38171369

RESUMO

Dear colleagues,When younger fellows ask for guidance on how to choose a research project, many aspects require consideration: how to select a supervisor and mentor, should one change the institution, how does the project boost the later professional career, what are personal and professional aims. As many can probably relate it is passion for the research topic, both by the fellow and the mentor, that will go a long way and most often result in successful project completion.


Assuntos
Glândulas Suprarrenais , Mentores , Humanos
3.
Horm Metab Res ; 56(4): 308-317, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37793428

RESUMO

The emergence of SARS-CoV 2 caused the COVID-19 pandemic, resulting in numerous global infections and deaths. In particular, people with metabolic diseases display an increased risk of severe COVID 19 and a fatal outcome. Treatment options for severe cases are limited, and the appearance of new virus variants complicates the development of novel therapies. To better manage viral infections like COVID 19, new therapeutic approaches are needed. Marine sponges offer a natural and renewable source of unique bioactive agents. These sponges produce secondary metabolites with various effects, including anti-viral, anti-inflammatory, and anti-tumorigenic properties. In the current study, we investigated the effect of five different marine sponge-derived secondary metabolites (four bromotyrosines and one sesquiterpenoid hydroquinone). Two of these, Avarol and Acetyl-dibromoverongiaquinol reduced the expression of ACE2, the main receptor for SARS-CoV 2, and the alternative receptor NRP1. Moreover, these substances derived from sponges demonstrated the ability to diminish the virus titer in SARS-CoV 2-infected cells, especially concerning the Omicron lineage. However, the reduction was not substantial enough to expect a significant impact on infected humans. Consequently, the investigated sponge-derived secondary metabolites are not likely to be effective to treat COVID 19 as a stand-alone therapy.


Assuntos
COVID-19 , Poríferos , Animais , Humanos , SARS-CoV-2 , Pandemias
4.
Horm Metab Res ; 56(1): 10-15, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37562416

RESUMO

Based on recent data, a total number of about 29 000 patients with adrenal insufficiency can be calculated for Germany, and about 1500 fatalities due to adrenal crises have to be expected within the next decade. Management of adrenal crises is still unsatisfactory. The objectives of this study were to establish consensus for diagnostic criteria, prevention strategies, and treatment recommendations for adrenal crises. The study was conducted from January 2022 to April 2023, using Delphi technique. Four rounds of questionnaires were sent to 45 experts, selected by a coordinating group on behalf of the adrenal section of the German Society of Endocrinology. The survey was implemented online using the REDCap web application. Responses were captured anonymously. During the Delphi process the expert panel developed diagnostic criteria to identify patients likely to have an adrenal crisis. Education about adrenal insufficiency among patients as well as non-endocrine medical personnel were regarded as highly important. It was suggested that recommendations for the management of adrenal insufficiency have to be simplified and made widely available. This study provides pragmatic strategies to identify and treat patients prone to adrenal crisis, thereby highlighting the need for an improved management of patients with adrenal insufficiency.


Assuntos
Insuficiência Adrenal , Endocrinologia , Humanos , Insuficiência Adrenal/diagnóstico , Insuficiência Adrenal/prevenção & controle , Inquéritos e Questionários , Alemanha/epidemiologia
5.
Mol Psychiatry ; 27(1): 34-37, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34140635

RESUMO

As millions of patients have been infected by SARS-CoV-2 virus a vast number of individuals complain about continuing breathlessness and fatigue even months after the onset of the disease. This overwhelming phenomenon has not been well defined and has been called "post-COVID syndrome" or "long-COVID" [1]. There are striking similarities to myalgic encephalomyelitis also called chronic fatigue syndrome linked to a viral and autoimmune pathogenesis. In both disorders neurotransmitter receptor antibodies against ß-adrenergic and muscarinic receptors may play a key role. We found similar elevation of these autoantibodies in both patient groups. Extracorporeal apheresis using a special filter seems to be effective in reducing these antibodies in a significant way clearly improving the debilitating symptoms of patients with chronic fatigue syndrome. Therefore, such a form of neuropheresis may provide a promising therapeutic option for patients with post-COVID-19 syndrome. This method will also be effective when other hitherto unknown antibodies and inflammatory mediators are involved.


Assuntos
Remoção de Componentes Sanguíneos , COVID-19 , Síndrome de Fadiga Crônica , COVID-19/complicações , Síndrome de Fadiga Crônica/diagnóstico , Síndrome de Fadiga Crônica/tratamento farmacológico , Humanos , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
6.
Horm Metab Res ; 54(8): 549-555, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35853464

RESUMO

COVID-19 may influence human fertility and sexuality in several ways. Different cell types in gonads show a constitutive expression of angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine subtype 2 (TMPRSS2), which provide potential entry pathways for SARS-CoV-2. In addition to the biological effects of a COVID-19 infection on the gonads, the impact of the ongoing COVID-19 pandemic on mental health issues and sexual behavior may affect reproduction. This review summarizes the current knowledge on the influence of COVID-19 on the gonads and discusses possible consequences on human fertility. In this context, the close interaction between the hypothalamic-pituitary-adrenal axis and the hypothalamic-pituitary-gonadal axis in response to COVID-19-related stress is discussed. Some women noticed changes in their menstrual cycle during the COVID-19 pandemic, which could be due to psychological stress, for example. In addition, occasional cases of reduced oocyte quality and ovarian function are described after COVID-19 infection. In men, COVID-19 may cause a short-term decrease in fertility by damaging testicular tissue and/or impairing spermatogenesis. Moreover, decreased ratio testosterone/LH and FSH/LH in COVID-19 compared to aged-matched healthy men has been reported. Available data do not suggest any effect of the available SARS-CoV-2 vaccines on fertility. The effects of long COVID on human fertility have been reported and include cases with premature ovarian failure and oligomenorrhoea in women and erectile dysfunction in men. Despite the increasing knowledge about the effects of COVID-19 infections on human gonads and fertility, the long-term consequences of the COVID-19 pandemic cannot yet be assessed in this context.


Assuntos
COVID-19 , Idoso , COVID-19/complicações , Vacinas contra COVID-19 , Feminino , Fertilidade , Gônadas , Humanos , Sistema Hipotálamo-Hipofisário , Masculino , Pandemias , Sistema Hipófise-Suprarrenal , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
7.
World J Urol ; 40(2): 385-390, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34655306

RESUMO

PURPOSE: Paraganglioma of the urinary bladder (UBPGL) is a rare neuroendocrine tumor diagnosed in many patients only after surgery. We, therefore, assessed clinical clues relevant to presurgical diagnosis and clinical consequences in patients with a missed presurgical diagnosis of UBPGL. MATERIALS AND METHODS: Case reports describing a UBPGL (published from 1-1-2001 and 31-12-2020) were identified in Pubmed. Two authors independently performed data extraction and assessed data quality according to the PRISMA guideline. Patients were divided into two groups: UBPGL diagnosis before and after surgery. RESULTS: We included 177 articles reporting 194 cases. In 90 (46.4%) patients, the UBPGL was diagnosed before and in 104 (53.6%) after surgery. In presurgically diagnosed UBPGL, hypertension and catecholamine-associated symptoms were 2- to 3-fold (p < 0.001) more frequent than in postsurgically diagnosed patients whereas hematuria was twofold (p = 0.003) more prevalent in those with postsurgical diagnosis. Hypertension was an independent factor for presurgical biochemical testing (OR 4.45, 95% CI 1.66-11.94) while hematuria (OR 0.23, 95% CI 0.09-0.60) was an independent factor for not performing presurgical biochemical testing. Most patients diagnosed after surgery were not pretreated with alpha-adrenoceptor blockade (95.2%), underwent more frequently transurethral resection instead of cystectomy (70.2% vs. 23.1%) and had more frequent peroperative complications and residual tumor mass. CONCLUSIONS: In nearly half of all patients with a UBPGL, the diagnosis was not established before surgery. Hypertension and hematuria contributed independently to a presurgical diagnosis. Postsurgical diagnosis, which was associated with suboptimal presurgical and surgical management, resulted in more peroperative complications and incomplete tumor resections.


Assuntos
Paraganglioma , Neoplasias da Bexiga Urinária , Cistectomia/métodos , Hematúria , Humanos , Paraganglioma/diagnóstico , Paraganglioma/patologia , Paraganglioma/cirurgia , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
8.
Cell Mol Life Sci ; 78(7): 3577-3590, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33464382

RESUMO

Endogenous steroid hormones, especially glucocorticoids and mineralocorticoids, derive from the adrenal cortex, and drastic or sustained changes in their circulatory levels affect multiple organ systems. Although hypoxia signaling in steroidogenesis has been suggested, knowledge on the true impact of the HIFs (Hypoxia-Inducible Factors) in the adrenocortical cells of vertebrates is scant. By creating a unique set of transgenic mouse lines, we reveal a prominent role for HIF1α in the synthesis of virtually all steroids in vivo. Specifically, mice deficient in HIF1α in adrenocortical cells displayed enhanced levels of enzymes responsible for steroidogenesis and a cognate increase in circulatory steroid levels. These changes resulted in cytokine alterations and changes in the profile of circulatory mature hematopoietic cells. Conversely, HIF1α overexpression resulted in the opposite phenotype of insufficient steroid production due to impaired transcription of necessary enzymes. Based on these results, we propose HIF1α to be a vital regulator of steroidogenesis as its modulation in adrenocortical cells dramatically impacts hormone synthesis with systemic consequences. In addition, these mice can have potential clinical significances as they may serve as essential tools to understand the pathophysiology of hormone modulations in a number of diseases associated with metabolic syndrome, auto-immunity or even cancer.


Assuntos
Glândulas Suprarrenais/metabolismo , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Esteroides/biossíntese , Animais , Feminino , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
9.
Horm Metab Res ; 53(5): 326-334, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33902135

RESUMO

The adrenal gland is important for many physiological and pathophysiological processes, but studies are often restricted by limited availability of sample material. Improved methods for sample preparation are needed to facilitate analyses of multiple classes of adrenal metabolites and macromolecules in a single sample. A procedure was developed for preparation of chromaffin cells, mouse adrenals, and human chromaffin tumors that allows for multi-omics analyses of different metabolites and preservation of native proteins. To evaluate the new procedure, aliquots of samples were also prepared using conventional procedures. Metabolites were analyzed by liquid-chromatography with mass spectrometry or electrochemical detection. Metabolite contents of chromaffin cells and tissues analyzed with the new procedure were similar or even higher than with conventional methods. Catecholamine contents were comparable between both procedures. The TCA cycle metabolites, cis-aconitate, isocitate, and α-ketoglutarate were detected at higher concentrations in cells, while in tumor tissue only isocitrate and potentially fumarate were measured at higher contents. In contrast, in a broad untargeted metabolomics approach, a methanol-based preparation procedure of adrenals led to a 1.3-fold higher number of detected metabolites. The established procedure also allows for simultaneous investigation of adrenal hormones and related enzyme activities as well as proteins within a single sample. This novel multi-omics approach not only minimizes the amount of sample required and overcomes problems associated with tissue heterogeneity, but also provides a more complete picture of adrenal function and intra-adrenal interactions than previously possible.


Assuntos
Glândulas Suprarrenais/química , Glândulas Suprarrenais/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Hormônios/metabolismo , Espectrometria de Massas/métodos , Metabolômica/métodos , Neoplasias das Glândulas Suprarrenais/química , Neoplasias das Glândulas Suprarrenais/metabolismo , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Paraganglioma/química , Paraganglioma/metabolismo , Feocromocitoma/química , Feocromocitoma/metabolismo
10.
Clin Chem Lab Med ; 59(2): 353-363, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001846

RESUMO

Objectives: Plasma free metanephrines are commonly used for diagnosis of pheochromocytoma and paraganglioma (PPGLs), but can also provide other information. This multicenter study prospectively examined whether tumor size, location, and mutations could be predicted by these metabolites. Methods: Predictions of tumor location, size, and mutation type, based on measurements of plasma normetanephrine, metanephrine, and methoxytyramine were made without knowledge of disease in 267 patients subsequently determined to have PPGLs. Results: Predictions of adrenal vs. extra-adrenal locations according to increased plasma concentrations of metanephrine and methoxytyramine were correct in 93 and 97% of the respective 136 and 33 patients in who these predictions were possible. Predicted mean tumor diameters correlated positively (p<0.0001) with measured diameters; predictions agreed well for pheochromocytomas but were overestimated for paragangliomas. Considering only patients with mutations, 51 of the 54 (94%) patients with NF1 or RET mutations were correctly predicted with those mutations according to increased plasma metanephrine, whereas no or minimal increase in metanephrine correctly predicted all 71 patients with either VHL or SDHx mutations; furthermore, among the latter group increases in methoxytyramine correctly predicted SDHx mutations in 93% of the 29 cases for this specific prediction. Conclusions: Extents and patterns of increased plasma O-methylated catecholamine metabolites among patients with PPGLs allow predictions of tumor size, adrenal vs. extra-adrenal locations and general types of mutations. Predictions of tumor location are, however, only possible for patients with clearly increased plasma methoxytyramine or metanephrine. Where possible or clinically relevant the predictions are potentially useful for subsequent clinical decision-making.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Biomarcadores Tumorais/sangue , Metanefrina/sangue , Paraganglioma/diagnóstico , Feocromocitoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Dopamina/análogos & derivados , Dopamina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neurofibromatose 1/genética , Normetanefrina/sangue , Estudos Prospectivos , Proto-Oncogenes/genética , Fatores de Risco
11.
Mar Drugs ; 18(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32369901

RESUMO

Novel strategies to treat cancer effectively without adverse effects on the surrounding normal tissue are urgently needed. Marine sponges provide a natural and renewable source of promising anti-tumor agents. Here, we investigated the anti-tumor activity of Aerothionin and Homoaerothionin, two bromotyrosines isolated from the marine demosponge Aplysina cavernicola, on two mouse pheochromocytoma cells, MPC and MTT. To determine the therapeutic window of these metabolites, we furthermore explored their cytotoxicity on cells of the normal tissue. Both metabolites diminished the viability of the pheochromocytoma cell lines significantly from a concentration of 25 µM under normoxic and hypoxic conditions. Treatment of MPC cells leads moreover to a reduction in the number of proliferating cells. To confirm the anti-tumor activity of these bromotyrosines, 3D-pheochromocytoma cell spheroids were treated with 10 µM of either Aerothionin or Homoaerothionin, resulting in a significant reduction or even complete inhibition of the spheroid growth. Both metabolites reduced viability of normal endothelial cells to a comparable extent at higher micromolar concentration, while the viability of fibroblasts was increased. Our in vitro results show promise for the application of Aerothionin and Homoaerothionin as anti-tumor agents against pheochromocytomas and suggest acceptable toxicity on normal tissue cells.


Assuntos
Antineoplásicos/farmacologia , Isoxazóis/farmacologia , Poríferos/química , Compostos de Espiro/farmacologia , Tirosina/análogos & derivados , Animais , Células 3T3 BALB/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Modelos Animais de Doenças , Camundongos , Tirosina/farmacologia
12.
Mar Drugs ; 18(6)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32531909

RESUMO

Chitin, as one of nature's most abundant structural polysaccharides, possesses worldwide, high industrial potential and a functionality that is topically pertinent. Nowadays, the metallization of naturally predesigned, 3D chitinous scaffolds originating from marine sponges is drawing focused attention. These invertebrates represent a unique, renewable source of specialized chitin due to their ability to grow under marine farming conditions. In this study, the development of composite material in the form of 3D chitin-based skeletal scaffolds covered with silver nanoparticles (AgNPs) and Ag-bromide is described for the first time. Additionally, the antibacterial properties of the obtained materials and their possible applications as a water filtration system are also investigated.


Assuntos
Antibacterianos/farmacologia , Quitina/química , Escherichia coli/efeitos dos fármacos , Poríferos , Animais , Organismos Aquáticos , Nanopartículas Metálicas/química , Prata/química , Relação Estrutura-Atividade
13.
Mar Drugs ; 17(2)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717221

RESUMO

The bioactive bromotyrosine-derived alkaloids and unique morphologically-defined fibrous skeleton of chitin origin have been found recently in marine demosponges of the order Verongiida. The sophisticated three-dimensional (3D) structure of skeletal chitinous scaffolds supported their use in biomedicine, tissue engineering as well as in diverse modern technologies. The goal of this study was the screening of new species of the order Verongiida to find another renewable source of naturally prefabricated 3D chitinous scaffolds. Special attention was paid to demosponge species, which could be farmed on large scale using marine aquaculture methods. In this study, the demosponge Pseudoceratina arabica collected in the coastal waters of the Egyptian Red Sea was examined as a potential source of chitin for the first time. Various bioanalytical tools including scanning electron microscopy (SEM), fluorescence microscopy, FTIR analysis, Calcofluor white staining, electrospray ionization mass spectrometry (ESI-MS), as well as a chitinase digestion assay were successfully used to confirm the discovery of α-chitin within the skeleton of P. arabica. The current finding should make an important contribution to the field of application of this verongiid sponge as a novel renewable source of biologically-active metabolites and chitin, which are important for development of the blue biotechnology especially in marine oriented biomedicine.


Assuntos
Quitina/química , Poríferos/química , Animais , Quitina/isolamento & purificação , Quitina/ultraestrutura , Oceano Índico , Microscopia Eletrônica de Varredura/métodos , Poríferos/ultraestrutura , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Mar Drugs ; 17(2)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813373

RESUMO

Sponges are a valuable source of natural compounds and biomaterials for many biotechnological applications. Marine sponges belonging to the order Verongiida are known to contain both chitin and biologically active bromotyrosines. Aplysina archeri (Aplysineidae: Verongiida) is well known to contain bromotyrosines with relevant bioactivity against human and animal diseases. The aim of this study was to develop an express method for the production of naturally prefabricated 3D chitin and bromotyrosine-containing extracts simultaneously. This new method is based on microwave irradiation (MWI) together with stepwise treatment using 1% sodium hydroxide, 20% acetic acid, and 30% hydrogen peroxide. This approach, which takes up to 1 h, made it possible to isolate chitin from the tube-like skeleton of A. archeri and to demonstrate the presence of this biopolymer in this sponge for the first time. Additionally, this procedure does not deacetylate chitin to chitosan and enables the recovery of ready-to-use 3D chitin scaffolds without destruction of the unique tube-like fibrous interconnected structure of the isolated biomaterial. Furthermore, these mechanically stressed fibers still have the capacity for saturation with water, methylene blue dye, crude oil, and blood, which is necessary for the application of such renewable 3D chitinous centimeter-sized scaffolds in diverse technological and biomedical fields.


Assuntos
Quitina/isolamento & purificação , Poríferos/química , Animais , Materiais Biocompatíveis/análise , Materiais Biocompatíveis/química , Materiais Biocompatíveis/isolamento & purificação , Quitina/análise , Quitina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tirosina/análogos & derivados , Tirosina/análise , Tirosina/química , Tirosina/isolamento & purificação
15.
Mar Drugs ; 17(10)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658704

RESUMO

Naturally occurring three-dimensional (3D) biopolymer-based matrices that can be used in different biomedical applications are sustainable alternatives to various artificial 3D materials. For this purpose, chitin-based structures from marine sponges are very promising substitutes. Marine sponges from the order Verongiida (class Demospongiae) are typical examples of demosponges with well-developed chitinous skeletons. In particular, species belonging to the family Ianthellidae possess chitinous, flat, fan-like fibrous skeletons with a unique, microporous 3D architecture that makes them particularly interesting for applications. In this work, we focus our attention on the demosponge Ianthella flabelliformis (Linnaeus, 1759) for simultaneous extraction of both naturally occurring ("ready-to-use") chitin scaffolds, and biologically active bromotyrosines which are recognized as potential antibiotic, antitumor, and marine antifouling substances. We show that selected bromotyrosines are located within pigmental cells which, however, are localized within chitinous skeletal fibers of I. flabelliformis. A two-step reaction provides two products: treatment with methanol extracts the bromotyrosine compounds bastadin 25 and araplysillin-I N20 sulfamate, and a subsequent treatment with acetic acid and sodium hydroxide exposes the 3D chitinous scaffold. This scaffold is a mesh-like structure, which retains its capillary network, and its use as a potential drug delivery biomaterial was examined for the first time. The results demonstrate that sponge-derived chitin scaffolds, impregnated with decamethoxine, effectively inhibit growth of the human pathogen Staphylococcus aureus in an agar diffusion assay.


Assuntos
Organismos Aquáticos/química , Quitina/química , Portadores de Fármacos/química , Poríferos/química , Tirosina/análogos & derivados , Animais , Antibacterianos/administração & dosagem , Quitina/isolamento & purificação , Citoesqueleto/química , Compostos de Decametônio/administração & dosagem , Portadores de Fármacos/isolamento & purificação , Hidrocarbonetos Bromados/química , Hidrocarbonetos Bromados/isolamento & purificação , Isoxazóis/química , Isoxazóis/isolamento & purificação , Testes de Sensibilidade Microbiana , Peptídeos Cíclicos/química , Peptídeos Cíclicos/isolamento & purificação , Poríferos/citologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Tirosina/química , Tirosina/isolamento & purificação
16.
Int J Mol Sci ; 20(20)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618840

RESUMO

Marine sponges remain representative of a unique source of renewable biological materials. The demosponges of the family Ianthellidae possess chitin-based skeletons with high biomimetic potential. These three-dimensional (3D) constructs can potentially be used in tissue engineering and regenerative medicine. In this study, we focus our attention, for the first time, on the marine sponge Ianthella labyrinthus Bergquist & Kelly-Borges, 1995 (Demospongiae: Verongida: Ianthellidae) as a novel potential source of naturally prestructured bandage-like 3D scaffolds which can be isolated simultaneously with biologically active bromotyrosines. Specifically, translucent and elastic flat chitinous scaffolds have been obtained after bromotyrosine extraction and chemical treatments of the sponge skeleton with alternate alkaline and acidic solutions. For the first time, cardiomyocytes differentiated from human induced pluripotent stem cells (iPSC-CMs) have been used to test the suitability of I. labyrinthus chitinous skeleton as ready-to-use scaffold for their cell culture. Results reveal a comparable attachment and growth on isolated chitin-skeleton, compared to scaffolds coated with extracellular matrix mimetic Geltrex®. Thus, the natural, unmodified I. labyrinthus cleaned sponge skeleton can be used to culture iPSC-CMs and 3D tissue engineering. In addition, I. labyrinthus chitin-based scaffolds demonstrate strong and efficient capability to absorb blood deep into the microtubes due to their excellent capillary effect. These findings are suggestive of the future development of new sponge chitin-based absorbable hemostats as alternatives to already well recognized cellulose-based fabrics.


Assuntos
Organismos Aquáticos/química , Materiais Biocompatíveis/química , Produtos Biológicos/química , Poríferos/química , Animais , Curativos Biológicos , Quitina/química , Humanos , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais/química
17.
Molecules ; 24(20)2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31623238

RESUMO

Chitin, as a fundamental polysaccharide in invertebrate skeletons, continues to be actively investigated, especially with respect to new sources and the development of effective methods for its extraction. Recent attention has been focused on marine crustaceans and sponges; however, the potential of spiders (order Araneae) as an alternative source of tubular chitin has been overlooked. In this work, we focused our attention on chitin from up to 12 cm-large Theraphosidae spiders, popularly known as tarantulas or bird-eating spiders. These organisms "lose" large quantities of cuticles during their molting cycle. Here, we present for the first time a highly effective method for the isolation of chitin from Caribena versicolor spider molt cuticle, as well as its identification and characterization using modern analytical methods. We suggest that the tube-like molt cuticle of this spider can serve as a naturally prefabricated and renewable source of tubular chitin with high potential for application in technology and biomedicine.


Assuntos
Quitina/química , Quitina/isolamento & purificação , Aranhas/química , Animais , Fracionamento Químico , Micro-Ondas , Muda , Análise Espectral
18.
Cell Tissue Res ; 374(3): 473-485, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30159755

RESUMO

Pheochromocytomas and paragangliomas (PGLs) due to mutations of succinate dehydrogenase (SDH) B, a subunit of the SDH complex with a role in the Krebs cycle and the respiratory chain, tend to be larger at diagnosis and more prone to metastatic disease than other tumors. This presentation contrasts with the behavior of some cell line models of SDHB impairment, which show reduced growth compared to wild type. We hypothesize that reduced growth of SDHB-impaired monolayer culture models might reflect lack of support from sources within the tumor microenvironment. The present study therefore investigates how the microenvironment, modeled here by fibroblast co-culture, modulates cell metabolism, growth and invasion in an Sdhb-impaired mouse pheochromocytoma cell line. We employed two different constructs of short hairpin RNA to knockdown Sdhb and compared growth in a monolayer with and without fibroblast co-culture. Sdhb-silenced cells showed functional impairment of SDH with elevated succinate to fumarate ratio and decreased oxidative capacity. Cell growth was delayed with an increase in doubling time of 2 h or 20 h. Clonogenic cell survival and viability, on the other hand, were either unchanged or increased compared to control. In standard monolayer culture, no differences in pro-metastatic features were present. Co-culture with primary mouse fibroblast reversed the difference of proliferation between control and Sdhb knockdown but was unable to significantly influence invasiveness under these culture conditions. Metabolic studies identified that lactate secreted by fibroblasts was taken up preferentially by Sdhb-silenced cells. In summary, the present study identified a potential role for the tumor microenvironment in influencing phenotypic features of SDHB-mutated PGLs, providing a basis for the use of therapies targeted towards the tumor microenvironment.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Fibroblastos/metabolismo , Feocromocitoma/metabolismo , Feocromocitoma/patologia , Succinato Desidrogenase/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Técnicas de Silenciamento de Genes , Inativação Gênica , Camundongos , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Succinato Desidrogenase/genética
20.
Mar Drugs ; 16(5)2018 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-29783778

RESUMO

Over 10% of pheochromocytoma and paraganglioma (PPGL) patients have malignant disease at their first presentation in the clinic. Development of malignancy and the underlying molecular pathways in PPGLs are poorly understood and efficient treatment strategies are missing. Marine sponges provide a natural source of promising anti-tumorigenic and anti-metastatic agents. We evaluate the anti-tumorigenic and anti-metastatic potential of Aeroplysinin-1 and Isofistularin-3, two secondary metabolites isolated from the marine sponge Aplysina aerophoba, on pheochromocytoma cells. Aeroplysinin-1 diminished the number of proliferating cells and reduced spheroid growth significantly. Beside these anti-tumorigenic activity, Aeroplysinin-1 decreased the migration ability of the cells significantly (p = 0.01), whereas, the invasion capacity was not affected. Aeroplysinin-1 diminished the high adhesion capacity of the MTT cells to collagen (p < 0.001) and, furthermore, reduced the ability to form spheroids significantly. Western Blot and qRT-PCR analysis showed a downregulation of integrin ß1 that might explain the lower adhesion and migration capacity after Aeroplysinin-1 treatment. Isofistularin-3 showed only a negligible influence on proliferative and pro-metastatic cell properties. These in vitro investigations show promise for the application of the sponge-derived marine drug, Aeroplysinin-1 as anti-tumorigenic and anti-metastatic agent against PPGLs for the first time.


Assuntos
Acetonitrilas/farmacologia , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Alcaloides/farmacologia , Antineoplásicos/farmacologia , Cicloexenos/farmacologia , Feocromocitoma/tratamento farmacológico , Poríferos/metabolismo , Acetonitrilas/isolamento & purificação , Acetonitrilas/uso terapêutico , Neoplasias das Glândulas Suprarrenais/patologia , Alcaloides/isolamento & purificação , Alcaloides/uso terapêutico , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Carcinogênese/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cicloexenos/isolamento & purificação , Cicloexenos/uso terapêutico , Regulação para Baixo , Integrina beta1/metabolismo , Masculino , Camundongos , Feocromocitoma/patologia , Ratos , Esferoides Celulares/efeitos dos fármacos
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