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Modifications of the composition or organization of the cancer cell membrane seem to be a promising targeted therapy. This approach can significantly enhance drug uptake or intensify the response of cancer cells to chemotherapeutics. There are several methods enabling lipid bilayer modifications, e.g., pharmacological, physical, and mechanical. It is crucial to keep in mind the significance of drug resistance phenomenon, ion channel and specific receptor impact, and lipid bilayer organization in planning the cell membrane-targeted treatment. In this review, strategies based on cell membrane modulation or reorganization are presented as an alternative tool for future therapeutic protocols.
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Membrana Celular , Sistemas de Liberación de Medicamentos , Neoplasias , Membrana Celular/metabolismo , Membrana Celular/patología , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patologíaRESUMEN
Estrogens can stimulate the development, proliferation, migration, and survival of target cells. These biological effects are mediated through their action upon the plasma membrane estrogen receptors (ERs). ERs regulate transcriptional processes by nuclear translocation and binding to specific response elements, which leads to the regulation of gene expression. This effect is termed genomic or nuclear. However, estrogens may exert their biological activity also without direct binding to DNA and independently of gene transcription or protein synthesis. This action is called non-genomic or non-nuclear. Through non-genomic mechanisms, estrogens can modify regulatory cascades such as MAPK, P13K, and tyrosine cascade as well as membrane-associated molecules such as ion channels and G-protein-coupled receptors. The recent studies on the mechanisms of estrogen action provide an evidence that non-genomic and genomic effects converge. An example of such convergence is the potential possibility to modulate gene expression through these two independent pathways. The understanding of the plasma membrane estrogen receptors is crucial for the development of novel drugs and therapeutic protocols targeting specific receptor actions.
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Membrana Celular/metabolismo , Estrógenos/fisiología , Regulación de la Expresión Génica , Receptores de Estrógenos/metabolismo , Transducción de Señal , GenomaRESUMEN
The knowledge of apoptotic mechanisms is essential in many biologic aspects related to both normal and neoplastic cells. Cell death by apoptosis is a very desirable way to eliminate unwanted cells: prevents release of the cellular content, which, in contrast to necrosis, provides no activation of inflammatory reactions. Apoptosis is a multistep process in where an extremely important role is played by caspases. Functions of caspases and their modifications are fundamental to understanding the signaling pathways responsible for regulation of apoptosis. These enzymes belong to a family of cysteine proteases that have the potential to destroy the enzymatic and structural proteins, and in the final stages of apoptosis, to lead to the disintegration of the cell. Apoptosis can be modulated by certain signaling pathway.
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Apoptosis/fisiología , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , HumanosRESUMEN
Osteopontin (OPN) and osteoprotegerin (OPG) are glycoproteins that participate in the regulation of tissue biomineralization. The aim of the project is to verify the hypothesis that the content of OPN and OPG in the aorta walls increases with the development of atherosclerosis and that these proteins are quantitatively related to the main proteins in the extracellular arteries matrix. Quantitative and qualitative analyses of the OPN and OPG content in 101 aorta sections have been conducted. Additionally, an enzyme-linked immunosorbent assay (ELISA) test has been performed to determine the collagen types I-IV and elastin content in the tissues. Correlations between the biochemical data and patients' age/sex, atherosclerosis stages, and calcification occurrences in the tissue have been established. We are the first to report correlations between OPN or OPG and various types of collagen and elastin content (OPG/type I collagen correlation: r = 0.37, p = 0.004; OPG/type II collagen: r = 0.34, p = 0.007; OPG/type III collagen: r = 0.39, p = 0.002, OPG/type IV collagen: r = 0.27, p = 0.03; OPG/elastin: r = 0.42, p = 0.001; OPN/collagen type I: r = 0.34, p = 0.007; OPN/collagen type II: r = 0.52, p = 0.000; OPN/elastin: r = 0.61, p = 0.001). OPN overexpression accompanies calcium deposit (CA) formation with the protein localized in the calcium deposit, whereas OPG is located outside the CA. Although OPN and OPG seem to play a similar function (inhibiting calcification), these glycoproteins have different tissue localizations and independent expression regulation. The independent expression regulation presumably depends on the factors responsible for stimulating the synthesis of collagens and elastin.
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Glycation consists in formation of advanced glycation end-products (AGE) during non-enzymatic reaction between reducing sugars and proteins, lipids or nucleic acids. This review is focused mainly on glycation of collagen and its role in acceleration of vascular disease. Collagen is an extracellular matrix protein characterized by unique structure forming fibrils with great anti-tensile and anti-breaking strength. The protein builds the connective tissue and is responsible for biomechanical properties of blood vessels. It is reported that higher content of glycated collagen correlates with lower elasticity and greater toughness of the vessel walls and, as a consequence, a faster rate of atherosclerosis development. Numerous mechanisms connected with AGE formation are involved in atherogenesis, among others: receptor-mediated production of free radicals, triggering an inflammatory process, activation of leukocytes and thrombocytes, facilitation of LDL binding, change in level of growth factors, adhesion molecules, MMP and some other proteins' expression. The coverages allow the development of therapeutic strategies to prevent or slow down the pathological processes connected with glycation of collagen and other proteins in the artery wall. The main strategies are based on limitation of exogenous AGE, consumption of products which contain rutin, treatment with drugs which inhibit AGE formation, such as pyridoxamine, and chemicals which are able to cleave already formed AGE protein-protein crosslinks, such as ALT-711.
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Arterias/fisiopatología , Aterosclerosis/metabolismo , Colágeno/metabolismo , Proteínas de la Matriz Extracelular/biosíntesis , Productos Finales de Glicación Avanzada/metabolismo , Fenómenos Biomecánicos , Tejido Conectivo/metabolismo , Elasticidad , Glicosilación , Humanos , Piridoxamina/metabolismo , Enfermedades Vasculares/metabolismoRESUMEN
The present study aimed to compare the action of advanced platelet-rich fibrin (A-PRF+) alone with the action of A-PRF+ combined with autologous gingival fibroblasts. The components released from A-PRF+ conditioned with autogenous fibroblasts that were quantified in the study were fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF), trans-forming growth factor-beta1 and 2 (TGFß1 and TGFß2), and soluble collagen. A-PRF+ combined with fibroblasts demonstrated significantly higher values of released VEGF at every time point and, after 7 days, significantly higher values of released TGFß2. A viability test after 72 h showed a significant increase in proliferation fibroblasts after exposition to the factors released from A-PRF+ combined with fibroblasts. Similarly, the degree of wound closure after 48 h was significantly higher for the factors released from A-RRF+ alone and the factors released from A-RRF+ combined with fibroblasts. These results imply that platelet-rich fibrin (PRF) enhanced with fibroblasts can be an alternative method of connective tissue transplantation.
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Collagen is one of the most abundant proteins in the human organism. It is the major component of the extracellular matrix. The protein is represented by 29 distinct types, which differ in structure, amount, tissue distribution and affinity to the other elements of ECM. It is reported that collagen is responsible for the maintenance of integrity, tensile strength and elasticity of the connective tissue. The properties plays crucial role in functioning of the blood vessel walls. This work is focused on arteries. There are found 14 types of collagen. They are located mainly in the basement membrane and subendothelium. The vessels contain mostly fibrillar collagen (types I, III and V), also fibril associated (XII, XIV, XVI, XXI), microfibril (VI), basement membrane associated (IV, XV, XVIII, XIX), membrane bound (XIII) and anchoring (VII) collagen.
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Arterias/metabolismo , Colágeno/metabolismo , Animales , Membrana Basal/metabolismo , Colágeno/química , Tejido Conectivo/metabolismo , Matriz Extracelular/metabolismo , Humanos , Microfibrillas/metabolismo , Resistencia a la Tracción/fisiologíaRESUMEN
The main purpose of current anticancer methods is to initiate intracellular mechanisms leading to cell death (apoptosis or necrosis). The most required way of cell death is apoptosis. It is genetically caused process of active cell destruction. Cells undergo apoptosis without losing integrity, lysis, inflammation and damage of neighboring cells. There are formed apoptotic bodies from death cells. Apoptotic bodies are taken up by phagocytes and neighboring cells, which may also activate an anti-inflammatory response, at least in macrophages. There are three stages of apoptosis: decision, commitment and execution phase with inner and outer pathways. The significant role play cysteine proteases called caspases. Caspases are proteolytically activated heterodimer enzymes. The cascade of caspases play the key role in executive phase of apoptosis. However, p53 also is crucial in cell death. Is protein as a transcription factor can modulate gene expression coding proteins involved in apoptosis regulation. Photodynamic therapy (PDT) is a promising technique in anticancer therapies. It requires three crucial components for initiation of photodynamic reaction: a photosensitizer that selectively bounds with tumor cells; oxygen and a source of proper light for dye excitation. In many studies are shown that photosensitizers localized in mitochondria induced are apoptosis inductors, in contrast to these dyes localized in lysosomes and cytoplasmatic membrane.
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Muerte Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Fotoquimioterapia , Animales , Caspasas/metabolismo , Humanos , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Collagen is one of main structural protein in organism. It plays a fundamental role in a lot of functions crucial for proper functioning connective tissue. The metabolism of the protein-production, modification and degradation should be balanced, in other situation appear serious health consequences, inter alia course of the arteriosclerosis, which is one of the most serious contemporary medical problem in developed countries, might be deteriorated. The collagen is crucial for the atherosclerotic plaque stability, if there is the deficiency of it, the blood vessels are more prone to rupture. On the other hand, accumulation of the protein leads to the arterial stenosis. It is suggested that collagen is involved in the calcification of atherosclerotic areas of the arteries, in binding of low density lipoproteins, stimulation of migration and apoptosis of arterial smooth muscle cells.
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Arterias/metabolismo , Arteriosclerosis/metabolismo , Colágeno/metabolismo , Lipoproteínas LDL/metabolismo , Músculo Liso Vascular/metabolismo , Tejido Conectivo/metabolismo , Matriz Extracelular/metabolismo , Humanos , Metabolismo de los Lípidos , Placa Aterosclerótica/metabolismo , Calcificación Vascular/metabolismoRESUMEN
Photodynamic therapy (PDT) is a method of cancer treatment that leads to the disintegration of cancer cells and has developed significantly in recent years. The clinically used photosensitizers are primarily porphyrin, which absorbs light in the red spectrum and their absorbance maxima are relatively short. This review presents group of compounds and their derivatives that are considered to be potential photosensitizers in PDT. Cyanine dyes are compounds that typically absorb light in the visible to near-infrared-I (NIR-I) spectrum range (750-900 nm). This meta-analysis comprises the current studies on cyanine dye derivatives, such as indocyanine green (so far used solely as a diagnostic agent), heptamethine and pentamethine dyes, squaraine dyes, merocyanines and phthalocyanines. The wide array of the cyanine derivatives arises from their structural modifications (e.g., halogenation, incorporation of metal atoms or organic structures, or synthesis of lactosomes, emulsions or conjugation). All the following modifications aim to increase solubility in aqueous media, enhance phototoxicity, and decrease photobleaching. In addition, the changes introduce new features like pH-sensitivity. The cyanine dyes involved in photodynamic reactions could be incorporated into sets of PDT agents.
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INTRODUCTION: Extracellular matrix (ECM) proteins have been associated with atherosclerotic complications, such as plaque rupture, calcification and aneurysm. It is not clear what role different types of collagen play in the pathomechanism of atherosclerosis. The aim of the study was to analyze the content of elastin and major types of collagen in the aortic wall and how they associated are with course of atherosclerosis. MATERIAL AND METHODS: In this work we present six biochemical parameters related to ECM proteins and collagen-specific amino acids (collagen type I, III, and IV, elastin, proline and hydroxyproline) analyzed in 106 patients' aortic wall specimens characterized by different degree of atherosclerosis. Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (LC/ESI-MS/MS), ELISA and immunohistochemical methods were used. The severity of atherosclerosis was assessed on the six-point scale of the American Heart Association, taking into account the number and location of foam cells, the presence of a fatty core, calcium deposits and other characteristic atherosclerotic features. RESULTS: The results show that there is a relationship between the content of collagen-specific amino acids and development of atherosclerosis. The degree of atherosclerotic lesions was negatively correlated with the content of proline, hydroxyproline and the ratio of these two amino acids. Calcium deposits and surrounding tissue were compared and it was demonstrated that the ratio of type I collagen to type III collagen was higher in the aortic tissue than in aortic calcification areas, while the ratio of collagen type III to elastin was smaller in the artery than in the calcium deposits. CONCLUSIONS: We suggest that increase in collagen type III presence in the calcification matrix may stem from disorders in the structure of the type I and III collagen fibers. These anomalous fibers are likely to favor accumulation of the calcium salts, an important feature of the process of atheromatosis.
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Aorta/metabolismo , Aterosclerosis/metabolismo , Colágeno/metabolismo , Elastina/metabolismo , Calcificación Vascular/metabolismo , Adulto , Anciano , Colágeno/análisis , Elastina/análisis , Femenino , Humanos , Hidroxiprolina/metabolismo , Masculino , Persona de Mediana Edad , Prolina/metabolismoRESUMEN
Atherosclerotic plaques are characterized by structural heterogeneity affecting aortic behaviour under mechanical loading. There is evidence of direct connections between the structural plaque arrangement and the risk of plaque rupture. As a consequence of aortic plaque rupture, plaque components are transferred by the bloodstream to smaller vessels, resulting in acute cardiovascular events with a poor prognosis, such as heart attacks or strokes. Hence, evaluation of the composition, structure, and biochemical profile of atherosclerotic plaques seems to be of great importance to assess the properties of a mechanically induced failure, indicating the strength and rupture vulnerability of plaque. The main goal of the research was to determine experimentally under uniaxial loading the mechanical properties of different types of the human abdominal aorta and human aortic atherosclerotic plaques identified based on vibrational spectra (ATR-FTIR and FT-Raman spectroscopy) analysis and validated by histological staining. The potential of spectroscopic techniques as a useful histopathological tool was demonstrated. Three types of atherosclerotic plaques - predominantly calcified (APC), lipid (APL), and fibrotic (APF) - were distinguished and confirmed by histopathological examinations. Compared to the normal aorta, fibrotic plaques were stiffer (median of EH for circumferential and axial directions, respectively: 8.15 MPa and 6.56 MPa) and stronger (median of σM for APLc = 1.57 MPa and APLa = 1.64 MPa), lipidic plaques were the weakest (median of σM for APLc = 0.76 MPa and APLa = 0.51 MPa), and calcified plaques were the stiffest (median of EH for circumferential and axial directions, respectively: 13.23 MPa and 6.67 MPa). Therefore, plaques detected as predominantly lipid and calcified are most prone to rupture; however, the failure process reflected by the simplification of the stress-stretch characteristics seems to vary depending on the plaque composition.
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Placa Aterosclerótica , Aorta , Humanos , RoturaRESUMEN
Photodynamic therapy (PDT) is currently one of the cancer treatment options. PDT requires the application of a photosensitizer (such as: porphyrins, chlorines, and phthalocyanines) that selectively targets malignant cells. It is a dilemma to find a proper photosensitizer. In our study, we have tested a new in-vitro group of cyanine dyes. These dyes are widely applied in biotechnology as fluorescent markers. Two malignant adenocarcinoma cell lines (MCF-7/WT and MCF-7/DOX) were investigated using photodynamic reaction (PDR) with four cyanine dyes (KF-570, HM-118, FBF-749, and ER-139). KF-570 and HM-118 were irradiated with red light (630â¯nm), whereas FBF-749 and ER-139 with green light (435â¯nm). To evaluate PDR efficiency, a clonogenic test was conducted. Apoptosis was investigated by TUNEL and NCA (neutral comet) assays. Proteins selected as indicators of the apoptotic pathway (AIF, sPLA2, Smac/Diablo) and intracellular response markers (SOD-1 and GST-pi) were detected using western blot. The highest number of apoptotic cells (ca. 100%) was observed after PDR with HM-118 and KF-570 in both conducted tests, in both cell lines. The results showed that HM-118 and KF-570 cyanine dyes demonstrated a major phototoxic effect causing apoptosis in doxorubicin-resistant and sensitive cell lines.
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Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Carbocianinas/farmacología , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Caspasa 3/metabolismo , Línea Celular Tumoral , Humanos , Células MCF-7RESUMEN
AIM: The cytotoxicity of marcaine was estimated in combination with a calcium channel blocker. In addition, the influence of marcaine and marcaine plus lekoptin on a model system using the H9C2 cardiac cell line was investigated. METHODS: Cells were incubated for five hours with marcaine, lekoptin, or with both drugs simultaneously. Apoptotic cells were detected using the TUNEL assay and the alkaline comet assay. Mitochondrial cell function after drug uptake was examined using the MTT assay. The concentration of MDA (malondialdehyde) -- the final product of fatty-acid peroxidation, was quantified spectrophotometrically. The expression of glutathione S-transferase pi (GST-pi) was detected by immunofluorescence (IF) and Western blotting (WB) and inducible nitric oxide synthase (iNOS) was assessed by immunocytochemical staining (ABC). RESULTS: Incubation with marcaine resulted in the highest number of apoptotic cells. After incubation with both marcaine and lekoptin, moderate damage to cells (54.2%+/-1.775% of DNA destruction) was observed. The highest levels of iNOS and GST-pi expression were observed in cells treated with marcaine and marcaine plus lekoptin. The characteristic nuclear GST-pi expression was observed in cells treated with both drugs. CONCLUSION: Lekoptin stimulated cells to proliferate. Marcaine caused membrane damage and ultimately cell death.
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Bupivacaína/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Verapamilo/farmacología , Anestésicos Locales/farmacología , Animales , Apoptosis/fisiología , Línea Celular , Antígeno Ki-67/metabolismo , Peroxidación de Lípido , Mioblastos/citología , Miocardio/citología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Oxidación-Reducción , RatasRESUMEN
Oxidative stress may be defined as an imbalance between reactive oxygen species (ROS) and the antioxidant defense system. It is now known that oxidative stress is involved in most of pathological states and diseases. ROS and other oxidants can cause oxidation of lipids, proteins and DNA with following tissue damage. Toxic products of oxidation proceed cytostatic effects causing membrane damage and lead into cell death via apoptosis or necrosis. The redox status of the cell is maintained by antioxidant enzymes such as superoxide dismuthase, catalase, glutathione S-transferase and other substances such as glutathione, vitamins E, C and A, which provide to eliminate ROS.
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Muerte Celular/fisiología , Estrés Oxidativo/fisiología , Animales , Antioxidantes/metabolismo , ADN/metabolismo , Humanos , Metabolismo de los Lípidos , Peroxidación de Lípido , Neoplasias/metabolismo , Proteínas/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
BACKGROUND/AIM: There is no satisfactory treatment of glioblastoma multiforme, a highly invasive brain tumor. The aim of this study was to analyze the cytotoxic effects of curcumin (CUR) alone and as a photosensitizer on glioblastoma cells. MATERIALS AND METHODS: The SNB-19 cells where incubated for 2 and 24 h with 5-200 mM of CUR. The cells were radiated with blue light (6 J/cm2) and compared to non-irradiated ones. The effects of treatment were assessed by measuring mitochondrial activity with the MTT method and apoptosis progression by flow cytometry. To investigate CUR uptake, fluorescence imaging of cells was performed. RESULTS: Photosensitization of CUR decreased the EC50 6.3 times when the incubation time was 2 h and over 90% of cells underwent apoptosis. The study of the uptake of CUR showed that during the 2 h, CUR was placed in the entire cytoplasm, and over time, its amount decreased and localized in the subcellular compartments. CONCLUSION: CUR is a promising medicament that can be used as a photosensitizer in photodynamic therapy for glioma treatment.
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Neoplasias Encefálicas/tratamiento farmacológico , Curcumina/farmacología , Glioblastoma/tratamiento farmacológico , Fármacos Fotosensibilizantes/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/efectos de los fármacos , Fotoquimioterapia/métodosRESUMEN
The aim of this work is to determine the impact of development of atherosclerosis on dissection of the human thoracic aorta on the basis of an analysis of the mechanical properties of the interfaces between its layers. The research material consisted of 17 pathologically unchanged aortae and 74 blood vessels with atherosclerotic lesions, which were classified according to the histological classification by Stary. The subject of the analysis were the interfaces between the adventitia and the media-intima complex (A-MIC) and between the intima and the media-adventitia complex (I-MAC). The mechanical properties of the above interfaces were determined by the peeling test in the longitudinal and circumferential directions. The results indicate that development of atherosclerosis reduces vessel wall resistance to delamination. The greatest risk of dissection occurs at stage IV of the disease. In this case, energy values are lower by about 28% for the I-MAC interface and by 39% for the A-MIC interface compared with normal tissues. Lower values of mean force and energy were obtained for the I-MAC interface, indicating that this interface is more susceptible to delamination. The mechanical properties of the A-MIC interfaces are directional.
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Aorta Torácica/fisiopatología , Aterosclerosis/fisiopatología , Túnica Íntima/fisiopatología , Resistencia Vascular/fisiología , Fenómenos Biomecánicos/fisiología , Humanos , Estrés MecánicoRESUMEN
OBJECTIVE: The signature processes during atherosclerosis development are arterial calcification and accumulation in the arterial walls of proteins that are specific to bone and cartilage, e.g., collagen type II. The purpose of this study was to characterize localization of collagen type II and quantify its content in human arteries. RESULTS: The study was conducted on sections of thoracic and abdominal aortas (n=97) subjected to histological evaluation and classified into six grades according to the Stary scale of the atherosclerosis severity. Three types of samples were distinguished from the group of arteries: (1) without macroscopically visible calcifications, (2) with macroscopically visible calcifications dispersed within the arterial wall, and (3) calcium deposits isolated from the walls tested with respect to the segment of the artery from which they had originated. The results demonstrate that both cholesterol and collagen type II content are significantly higher in samples with calcification, whereas collagen type II is localized mainly in the tissue around the calcium deposit. A positive correlation has been shown between the levels of collagen type II and cholesterol (r=0.57, P<.05). A similar trend was observed with respect to the grade of atherosclerosis (r=0.43, P<.05). CONCLUSIONS: The amount of collagen type II is higher in the tissue around the calcium deposit. The correlation was observed between the quantityof collagen type II, the grade of atherosclerosis, and cholesterol.
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Aorta Abdominal/química , Aorta Torácica/química , Enfermedades de la Aorta/metabolismo , Aterosclerosis/metabolismo , Calcio/análisis , Colágeno Tipo II/análisis , Calcificación Vascular/metabolismo , Adulto , Anciano , Aorta Abdominal/patología , Aorta Torácica/patología , Enfermedades de la Aorta/patología , Aterosclerosis/patología , Biomarcadores/análisis , Colesterol/análisis , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Placa Aterosclerótica , Índice de Severidad de la Enfermedad , Calcificación Vascular/patologíaRESUMEN
PURPOSE: There are two families of fibres taking part in the process of mechanical loads transfer, i.e. elastin and collagen fibres. Their number, spatial arrangement and specific properties determine the capacity of a blood vessels to resist mechanical loads resulting from the impact of blood on vessel walls. The purpose of the present paper is to define the load-bearing capacities of elastin and collagen scaffolds equivalent to natural fibre arrangements of human aorta and produced by selective digestion. METHODS: Samples of thoracic human aortas were digested by using phosphate buffer of trypsin at pH 8.0 for 22 hours in order to degrade elastin and by autoclaving followed by incubation in 90% formic acid for 22 hours. The efficacy of digestion was assessed immunohistochemically. Mechanical properties of pre-stretched native and digested samples were determined by uniaxial tensile test. RESULTS: Samples subjected to autoclaving have been successfully deprived of both types of collagen and elastin has been intact. Treatment with trypsin caused a removal of elastin and the presence of type I and IV collagen was demonstrated. Digestion of aortic samples either by formic acid or trypsin has resulted significantly decreasing mechanical properties in comparison with native samples. CONCLUSIONS: Collagen and elastin scaffold-like stuctures have been effectively produced by selective digestion of thoracic human aorta and their contribution to the load-bearing process was evaluated. Isolated collagen network are more durable and stiffer and less deformable than elastin network, hence are responsible for load-bearing process at higher strain since the range of working of elastin is at lower strain values.
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Aorta Torácica/fisiología , Colágeno/fisiología , Elastina/fisiología , Mecanotransducción Celular/fisiología , Modelos Cardiovasculares , Soporte de Peso/fisiología , Adulto , Fuerza Compresiva/fisiología , Simulación por Computador , Módulo de Elasticidad/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estrés Mecánico , Resistencia a la Tracción/fisiologíaRESUMEN
BACKGROUND: The principal sources of medical collagen are pork, calf skin and bone. There are now more studies on a much safer, alternative source of active collagen, mainly from aquatic life. Active collagen and its peptides FCP (fish collagen peptides) have already been extracted from the skin of salmon, cobia, hoki, tilapia, zebrafish, ling, shark, silver carp and also jellyfish. OBJECTIVES: The aim of the study is to evaluate the effect of fish collagen on human fibroblasts from gingiva. The cytotoxicity of the new formulation and induction of endogenous collagen was estimated by means of the collagen derived from fish skin. MATERIAL AND METHODS: Fish collagen was extracted from the skin of silver carp at 16 degrees Celsius. To compare the biocompatibility and endogenous collagen production Geistlich Bio-Gide® membrane was ordered in Geistlich Biomaterials (Geistich AG, Wolhusen, Switzerland). The culture of human fibroblasts was performed acc. to Saczko et al. The fibroblasts were treated 96 hours with 1.0%, 0.5% and 0.1% experimental collagen formulation to induce endogenous collagen production. The Sircol collagen assay was done to measure amount of collagen. Cell viability was assessed by measuring mitochondrial activity in MTT assay after 24 h followed by 24 h of incubation with experimental collagen formulation. Qualitative analysis was performed by immunocytochemically staining of collagen type I and III. RESULTS: Preparations of fish collagen are not cytotoxic at concentrations below 1%. Cells cultured in the presence of this product are characterized by a large number of endogenous collagen, which is comparable to the control. In case of porcine collagen membrane was noticed decreased to 83% production of endogenous collagen and reduction of cell viability to 69%. CONCLUSIONS: Our study showed that experimental fish collagen is an innovative product which may induce expression of endogenous collagen in fibroblasts.